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Organisationseinheit der BAM
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Abstract Hydrogenated nitrile butadiene rubber (HNBR) elastomer was thermo-oxidatively aged at different temperatures up to 150 °C. Fourier transform infrared spectroscopy (FTIR), compression stress relaxation (CSR) and international rubber hardness degree (IRHD) microhardness were used to characterise the chemo-mechanical changes of HNBR O-rings during thermo-oxidative ageing. FTIR shows the development of carbonyl, methyl and ester groups but the nitrile content was not affected by ageing. The effect of sample geometry during CSR was investigated. CSR data were converted through integrated kinetic laws. The conversion has proven its sensibility to detect heterogeneous ageing. This was confirmed by the IRHD measure-ments across the section of O-rings. The influence of compression during ageing was assessed through IRHD measurements across the section of compressed and uncom-pressed aged O-rings. The DLO effect was more pronounced in compressed O-rings. By applying the model of Wise et al., theoretical IRHD and oxidation profiles were determined on the basis of IRHD experimental data of compressed O-rings. Good agreements between the experimental and the theoretical IRHD profiles in the core region were obtained. However, near the edge, the theoretical IRHD values were overestimated.
Our earlier study based on historical and scientific analysis showed that Iranians used a considerable range of materials in the sizing process. Unlike many nations who used limited sizing materials to improve the mechanical strength and to smoothen the paper surface, Iranians have used various materials for sizing process from Taimurid (15th century) to Safawid (16th century) and Qajar (19th century) periods. Further to our earlier study on the Sizing Materials used in Persian manuscripts and miniature paintings, scientific analysis was carried out to investigate their behaviour against the mould fungus Aspergillus flavus. In the first stage fourteen different sizing materials that was identified from Persian historical recipes were reconstructed. In the second stage fungicidal property of each sizing samples against Aspergillus flavus fungus were identified that will be presented in this paper.
Packaging containers for dangerous goods that include aggressive liquids require that any packaging material that is based on high-density polyethylene has a high degree of stability and durability. This work is focused on testing the environmental stress cracking of the high-density polyethylenes used for such containers in contact with crop protection formulations, in particular, two model liquids established in Germany as standardized test media representatives for crop protection formulations containing the various admixtures typical for such products. One of the liquids is water-based and contains mostly surface-active ingredients, while the other is solvent-based and includes some emulsifiers. Originally established for pin impression tests, these model liquids and their individual components were here used for the first time as environmental media in the Full Notch Creep Test, which addresses the resistance against environmental stress cracking. The Full Notch Creep Test was carried out on five high-density polyethylene types with both model liquids, and also on one selected material with its components. The evaluation was focused on the fracture surface structures, which were visualized by a scanning electron microscope and by optical in situ imaging of the notch opening. While the water-based model liquid and its surface-active individual components induced environmental stress cracking with the characteristic pattern for a craze-crack mechanism and so-called brittle fracture on the surface, the solvent-based model liquid and its soluble ingredients exhibited rather ductile failure behavior, caused by the plasticizing effect on the polymer that reduced the yield stress of the high-density polyethylene.
For both cases, fracture surface analysis, together with side views of the crack opening, showed a clear relation between surface pattern, notch deformation (e.g., by blunting), or crack opening due to crack growth with time to failure and the solubility of the liquids in high-density polyethylene.
This chapter aims to give a brief introduction into the field of alkali activated materials (AAM) and their physicochemical material behavior when exposed to sulfuric acid and in biochemically aggressive sewer environments. Additionally, the differences in material behavior within chemical (abiotic) and microbially induced acid environments are highlighted. Finally, existing data on overall performance of AAM, compared to conventional concrete-based building materials in sewer systems will be discussed.
The aim of this chapter is to give an overview of basic and advanced state-of-the-art microstructural and spectroscopic analytics to investigate inorganic material corrosion in the context of biochemically aggressive sewers. The chapter covers optical methods, electron beam, X-ray and neutron techniques (SEM, MLA, XRF, XRD, CT, Neutron radiography and tomography), and spectroscopic methods (MAS-NMR, FT-IR, and Raman). For each technique, a short section on the fundamental scientific background of the method precedes and examples of data output from the latter in respect to the corrosion of cementitious materials including reinforced concrete is presented.
The main obstacle to bottom ash (BA) being used as a recycling aggregate is the content of salts and potential toxic elements (PTEs), concentrated in a layer that coats BA particles. This work presents a dry treatment for the removal of salts and PTEs from BA particles. Two pilotscale abrasion units (with/without the removal of the fine particles) were fed with different BA samples. The performance of the abrasion tests was assessed through the analyses of particle size and moisture, and that of the column leaching tests at solid-to-liquid ratios between 0.3 and 4. The results were: the particle-size distribution of the treated materials was homogeneous (25 wt % had dimensions <6.3 mm) and their moisture halved, as well as the electrical conductivity of the leachates. A significant decrease was observed in the leachates of the treated BA for sulphates (44%),
chlorides (26%), and PTEs (53% Cr, 60% Cu and 8% Mo). The statistical analysis revealed good correlations between chloride and sulphate concentrations in the leachates with Ba, Cu, Mo, and Sr, illustrating the consistent behavior of the major and minor components of the layer surrounding BA particles. In conclusion, the tested process could be considered as promising for the improvement of BA valorization.
Automotive engine lubricants
(2019)
In 2003, ASTM Manual 37, Fuels and Lubricants Handbook: Technology, Properties, Performance and Testing, featured a chapter discussing automotive lubricants, including engine oils, automatic transmission fluids, manual transmission fluids, gear lubricants, and greases. This chapter, by Schwartz, Tung, and McMillan, surveyed all of these classes of lubricants, up to its publication in 2003.
More recently, the period between 2003 and 2010 has been addressed as part of a book copublished by ASTM and SAE International (coeditors Simon Tung and George Totten), where Fox surveyed the development of engine oil specifications that emerged during those years.
This chapter surveys the evolution of engine oil design and testing since 2002 and concludes with insights into future directions offered by recent tribological research. Our objective is to provide a reader new to the field with an understanding of the following:
- Engine oil composition and formulation
- North American engine oil specification development, and an outline of emergent European specifications
- How emergent specifications and legislative requirements are linked to the introduction of new engine hardware
- How tribological innovation can contribute to future enhancements in engine efficiency
In parallel, we will provide several tables comparing groups of contemporaneous specifications.
With the advent of widely accessible and cost-effective next-generation sequencing technologies, it has become increasingly feasible to study insect immunity on a deep genomic or transcriptomic level. Here we introduce a protocol that is aimed at exploiting transcriptomic data to study immunity in non-model insect organisms. We provide instructions for an entire workflow, starting with successfiil extraction of insect RNA through to bioinformatic guidelines for the effective analysis of mRNA sequencing data. The RNA extraction procedure is based on TRIzol Reagent and a spin-column clean-up Step. The bioinformatic pipeline is intended to help users identify immune genes from de novo transcriptome data and includes guidelines for conducting differential gene expression analyses on transcriptomic data. The immune gene prediction method is based on inferring protein homologs with HMMERand Blastp and talces Advantage ofthe ImmunoDB database, which is a valuable resource for research on insect immune-related genes and gene families. The differential gene expression analysis procedure utilizes the DESeq2 package as implemented in R. We hope this protocol will serve as a usefi.il resource for researchers aiming to study immunity in non-model insect species.
This chapter offers observations and considerations concerning black writing inks encountered in writing supports transmitting documentary and literary texts of the late Antiquity and early Middle Ages. It discusses different types of inks, the Methods of their detection and their use in different times and geographical areas.
There is a strong need for cost-effective mitigation measures for
turnouts. SBB has initiated a series of examinations using different methodologies to gain a deeper understanding of the excitation mechanisms at low frequencies, in addition to that obtained in the RIVAS project. To date it is not yet clear what constitutes a complete measurement data set that would enable understanding most of the vibration excitation mechanisms in turnouts. Increasing vibration at turnouts in comparison to normal track is observed for all measured frequencies.
The different methodologies are presented in the paper. Under-sleeper pads (USP) are a cost-effective method to reduce vibration at frequencies above 63 Hz (1/3 octave), but there is probably no improvement for frequencies below 63 Hz. A first test of new frog geometry did not show relevant improvements in Vibration emission in comparison to a reference frog geometry. Axle box acceleration measurements are an interesting method to identify defects in a turnout. A specialized measurement system of rail roughness could identify certain geometry Problem areas for some frogs. Noise increases also are observed at turnouts for frequencies ranging between 80 to 1000 Hz. The use of railway source models to calculate
contact forces for ballasted track and turnouts seems promising, in particular for understanding the influence of ground.
The present contribution evaluates four measuring series made by the Federal Institute of Material Research and Testing for the relations between train speed and ground vibration amplitudes. This experimental evaluation is supported by the simulation of the train passages at the different sites by using appropriate excitation mechanisms and forces as well as layered soil models which have been derived from impact measurements at each site.
Subfloors are layered structures, consisting largely of porous building materials, such as screed. They are often suffering damage from tap water leakage, which is a typical problem in buildings, and which has largely contributed to repair costs of almost 3 billion Euro in 2018 alone in Germany. In this context, especially mould plays a role, which is both destroying the structure and posing severe health risks.
To determine the damaging effects of moisture, it is necessary to know the respective processes occurring in building materials, especially to quantify the amount of moisture and its progress in the material. In this study, humidity sensors are used to derive the material moisture experimentally.
Capacitive sensors recording the relative humidity are embedded into the screed and in the insulation materials such as expanded polystyrene, extruded polystyrene, perlite and glass wool. For the application in screed, the sensors need to be shielded against the aggressive alkaline materials. To ensure an appropriate exchange with the environment, a permeable membrane is requested. Different membrane materials have been investigated regarding their robustness and their permeability.
In the first experimental setup, two humidity sensor arrays with seven individual sensors are embedded in homogeneous screed samples. The measured corresponding relative humidity of the screed is converted to the material moisture based on the approach of Hillerborg. In a second experimental setup, a layered structure of a complete subfloor is built in a box of 0.8 m times 0.8 m. The humidity sensors are positioned in the different insulation materials of various thicknesses. By adding water, leakage damage is simulated and its progress and effect is investigated experimentally.
The investigations point at the question if the observed moisture is able to generate damage such as mould. The moisture and corresponding humidity values are discussed. It will be shown that this low-cost hygrometric approach can be used easily for moisture monitoring of screed and insulation materials as well
At the end of the sixteenth century, a number of relics and artefacts were discovered in Granada, Spain. They included what became known as the Lead Books of the Sacromonte, twenty-one written artefacts made of circular lead leaves engraved in archaic Arabic characters. The authorship was attributed to some Arab disciples of St James the Greater considered to be the first evangelisers of the Iberian Peninsula. The texts, the materiality and the circumstances of the discoveries fuelled a debate surrounding their authenticity that lasted more than two centuries, a debate so fierce and controversial that not even papal condemnation in 1682 was able to stop it. Soon after the discoveries were made public, scholars highlighted the many contradictions and errors of a historical, linguistic and theological nature present in the texts, identifying members of the local Morisco community as possible forgers. This article focuses on how the scholarly community of the sixteenth and seventeenth centuries handled these findings and looks at the methods employed by the scholars to evaluate the authenticity of the artefacts. It will also look at how the particular interests of the various authorities involved influenced the acceptance or dismissal of relevant academic results.
Exposure of pressure vessels to fire can result in catastrophic explosion and escalation of accidents. The safe transportation of cargo in pressure vessels therefore requires knowledge of what will happen to the cargo in the event of a vehicle derailment or rollover resulting in fire exposure. The chapter presents an overview of selected testing and modelling work undertaken to understand the thermohydraulic processes within a vessel that drive pressurization during fire. A series of experiments highlighting the importance of adequate design and selection of protection systems are summarized. It is concluded that pressure relief alone is typically insufficient to prevent vessel rupture, but the combination of relief and thermal coatings can be effective.
To better understanding the failure of adhesive joints tensile tests were carried out on miniature test specimens from Norway spruce in the synchrotron. Urea-formaldehyde resin was used as adhesive. e. For comparison purposes, tensile tests were carried out on solid wood and on bonded miniature tensile shear samples with acoustic emission. The acoustic emission signals of all the experiments occurred with classified pattern recognition. This resulted in two classes of signals for each two frequency peaks. One class consisted of the low-frequency and the other of the higher-frequency peak of higher intensity, but this was essentially independent from the structure (solid wood or plywood) and size scale of the test specimens. The influence of the adhesive layers was determined on wood test specimens on laboratory scale and on miniature test specimens with an adhesive layer and selected fiber orientations. This gave evidence that the sound emission signals from the failure of the adhesive layer presumably of the class with low frequency signals peak in the range of services can be assigned.
This chapter provides an introduction in secondary ion mass spectrometry as one of the leading surface chemical analysis and imaging techniques with molecular specificity in the field of material sciences. The physical basics of the technique are explained along with a description of the typical instrumental setups and their modes of operation. The application paragraph specifically focuses on nanoparticle analysis by SIMS in terms of surface spectrometry, imaging, analysis in organic and complex media, and depth profiling.
A review of the existing literature is provided, and selected studies are showcased. Limitations and pitfalls as well as current technical developments of SIMS application in nanoparticle surface chemical analysis are equally discussed.
A variety of methods used to prepare nano-objects for surface analysis are described along with information about when they might be best applied. Intrinsic properties of NPs which complicate their characterization and need to be considered when planning for surface or other analyses of NPs are identified, including challenges associated with reproducible synthesis and functionalization of the particles as well as their dynamic nature. The relevant information about the sample preparation processes, along with analysis details and data that need to be added to the collection of material provenance information is identified. Examples of protocols that have been successfully used for preparation of nano-objects for surface analysis are included in an annex.
Conclusions and perspectives
(2020)
This chapter briefly summarizes the methods selected within this book for the characterization of nanoparticles with regard to commonly accessible properties: nanoparticle size and size distribution, shape, surface area, surface charge, aggregation state, structure, chemical composition, surface chemistry, and nanoparticle number concentration. Current progress of measurement and analysis, as far as possible according to standard operation procedures, has been the focus of this work. A number of new and less commonly used methods have not been covered, and we outline some of these in this chapter. Future challenges such as automated measurement and analysis, read-across approaches for the prediction of properties, knowledge of measurement uncertainties, the need for certified reference materials, and the necessity to complement measurements methods to obtain more reliable results are covered, and the unmet measurement requirements for real-world nanoparticles are described.
Introduction
(2020)
The purpose of this book is to provide a comprehensive collection of analytical methods that are commonly used to measure nanoparticles, providing information on one, or more, property of importance. The chapters provide up-to-date information and guidance on the use of these techniques, detailing the manner in which they may be reliably employed. Within this chapter, we detail the rationale and context of the whole book, which is driven by the observation of a low level of reproducibility in nanoparticle research. The aim of the book is to encourage awareness of both the strengths and weaknesses of the various methods used to measure nanoparticles and raise awareness of the range of methods that are available. The editors of the book have, for many years, been engaged in European projects and standardization activities concerned with nanoparticle analysis and have identified authors who are experts in the various methods included within the book. This has produced a book that can be used as a definitive guide to current best practice in nanoparticle measurement.
This chapter provides an overview of what standards are, why they are important, and how they are developed. There is a focus on the work of standards committees relevant to nanotechnology measurement and characterization with tables detailing the standards that are currently available for a large number of different techniques, materials, and applications at the nanoscale.
Characterization of nanomaterials by transmission electron microscopy - Measurement procedures
(2020)
In this chapter, approaches are proposed for the descriptive and quantitative characterization of nano-objects with nanometer resolution. Measurements are based on the analysis of the characteristics of 2D projections of individual particles visualized on transmission electron micrographs.
Incorporation of spectroscopic methods (EDS and EELS) for elemental analysis of nano-objects is recommended to identify subpopulations of nano-objects in mixtures based on their chemical composition. The focus lies on the determination of physicochemical properties which are essential in a legislatory and regulatory context to define the material as a nanomaterial (NM), and to assess its safety and toxicological potential, using widely accessible equipment.
In this chapter sample preparation, image acquisition, and nanoparticle size and shape characterization methods using the scanning electron microscope (SEM) in reflective and transmitted working modes are described. These help in obtaining reliable, highly repeatable results. The best solutions vary case-by-case and depend on the raw (powdered or suspension) nanoparticle material, the required measurement uncertainty and on the performance of the SEM.
Auger electron spectroscopy
(2020)
An introduction in the application of Auger Electron Spectroscopy to surface chemical analysis of nanoparticles is given. Auger Electron Spectroscopy is a mature method in the field of surface chemical analysis. The chapter addresses the physical basis of the method, the principal design of recent instruments together with modes of operation and options for the presentation of spectra, as well as different approaches for qualitative (including identification of chemical species) and quantitative surface analysis of elements. An application paragraph on surface chemical analysis of nanoparticles by AES or SAM introduces the different measurement approaches and sample preparation strategies applied by analysts. The analysis of nanoparticle ensembles, the so-called selected point analysis where a narrow primary electron beam is centered on an individual nanoparticle, and chemical mapping of individual nanoparticles (or a line scan across) are addressed. Existing literature is reviewed and informative case studies presented. Limitations and pitfalls in the application of AES in surface chemical analysis of nanoparticles are also addressed.
The described investigation of carbon-fibre-reinforced plastics (CFRP) documents that damage evolution can be observed by means of X-ray refractography. Comparative investigations with synchrotron technique on CFRP and grey-scale analysis on glass fibre-reinforced-plastics (GFRP) confirm these results. Moreover it was found that the fracture mechanical properties of the matrix system influence damage nucleation and propagation in the laminate during static and fatigue loads. Single-step fatigue tests were carried out on Laminates with RIM135 and LY556 matrix systems made from non-crimped fabric (NCF) or twill weave in different fibre orientations. The damage to the LY556 laminates was characterized by laminate cracks growing rapidly over the whole specimen width, whereas the damage on the RIM135 laminates was characterized by an earlier onset of micro-cracking followed by laminate cracks. The specimens were fatigued up to 108 (very high cycle fatigue (VHCF) regime) load cycles. S-N-curves of damage initiation were drawn and boundaries were identified for endurance within the VHCF regime. A phenomenology based model focusing on matrix stress was applied to reproduce the first inter-fibre failure (IFF) under static and fatigue loads.
As one of the widely used analytical methods for the analysis of elemental composition of solid matter, energy dispersive X-ray spectroscopy (EDS) has recently gained significant importance regarding its application to the chemical analysis of nanoparticles, especially in conjunction with the use of a scanning electron microscope (SEM) and the use of the transmission operation mode of SEM (STEM-in-SEM). This development was mainly driven by the technological progress with highly sensitive EDS detectors, such that individual nanoparticles can be quickly inspected with EDS at a SEM. Qualitative information on elemental composition with about 10 nm spatial resolution can be achieved complementary to the high-resolution information of the sample surface morphology within the same scanned area as provided by the electron microscope. Representative examples with successful EDS analysis on nanoparticles are presented, but also limitations of the method are described.
This chapter first gives an introduction to the concepts of SSA and volume-specific surface area (VSSA) and an outline of the BET method. It continues with a discussion of the relationship between particle size, shape, and the VSSA, followed by an overview of instrumentation, experimental methods, and standards. Finally, sections on the use of the VSSA as a tool to identify nanomaterials and non-nanomaterials and its role in a regulatory context provide some insight on the importance of VSSA in the current Regulation of nanomaterials.
Humidity is one of principal environmental parameters that plays an important role in various application areas. Using measurement of strain induced in an optical fiber by a water swellable coating represents a promising approach for realization of distributed humidity sensing (DHS). In this work, humidity and temperature response of four different commercial PI-coated fibers and four tight-buffered (TB) fibers is investigated with the aim of evaluating their potential for development of DHS in context of water ingress sensor for high-voltage power cable splices. PI-coated fibers exhibited close-to-linear humidity and temperature response. While the temperature response is relatively coating-independent, magnitude of humidity response was broadly correlated to the relative fiber-to-coating thickness ratio. In contrast, both humidity and temperature response of TB fibers is strongly influenced by buffer type, with Leoni TB900L fiber with Hytrel buffer exhibiting largest humidity and temperature sensitivity. While the response of tight-buffered fibers is generally nonlinear, roughly three-times higher humidity response can be achieved with TB900L compared to the most sensitive PI-coated fiber. Using the TB fiber can be, therefore, advantageous for simpler water detection applications, such as one targeted in this study, when larger sensitivity is more important than the linear response of the sensor.
The reuse of existing foundations is considered in various construction Projects to save time and costs while avoiding unnecessary interference with other underground objects. Because the design and as-built drawings might not be complete and questions may arise regarding the condition of the foundations, a detailed investigation is a prerequisite for the planning process in most cases. Nondestructive testing (NDT) techniques are a core part of this endeavor.
The processes and procedure for foundation reuse planning are not yet standardized, and the possibilities and limitations of NDT methods are not known to many planners and stakeholders. The German research Project REFUND (2014–2016) has developed charts for the planning and Investigation process that consider available standards and the current state of the art in NDT.
These charts are separately available for single and strip, slab, and pile foundations. Available NDT methods have been compiled and evaluated for specific tasks at these foundation types, including their respective limitations.
The procedures have been successfully tested in two real-world projects. The results from these projects enable planners to improve the reliability of the process while potentially saving significant resources. This paper discusses the procedures for pile foundations and demonstrates the use of various NDT methods in a project on the reuse of electrical tower foundations.
Concrete piles are used as a foundation when the load capacity of the soil is insufficient or when the sustainable soil is found at a higher depth. Among other impact factors, the load capacity depends on the pile’s integrity and length.
Therefore, verifying these parameters using adequate methods is recommended. The most common procedure is the low-strain integrity test using the hammer impact method. Developed and established in the 1970s, this method uses stress waves induced by a hammer impact at the pile head and its reflections at impedance changes (length, defects, geometry changes) to estimate the length and defect locations. Although this method is widely used due to its low cost and fast conduction in situ, one disadvantage is its inability to classify the exact type of defect, i.e., crack, change in diameter, or concrete quality. Furthermore, very long and slender piles are difficult to test and small defects cannot be detected. In addition, it is necessary for the test engineer to hold a high level of experience and expertise in this field. The European Union–funded PileInspect project (2013–2016) aimed to compensate for these disadvantages by using a low-cost shaker as the excitation source and sophisticated artificial intelligence algorithms for damage detection (higher-order spectra method). Because this technology lacks the capacity to localize damages and verify the pile length, an additional impulse response (IR) measurement technique was developed using vibrational excitation and regularized deconvolution to extract the depth information from the data in a similar manner as the hammer method.
Simulations and subsequent experiments conducted at a test facility on 90-cm-diameter bored piles 11 m in length and containing cracks at approximately 4 m below the pile head confirmed the capacity to determine the pile length.
Damage diagnosis and localization, however, are more difficult than for the hammer method. Although the damaged piles could be distinguished from the intact piles, in a blind test, this method might lead to misinterpretations caused by perturbations arising from the deconvolution process. The results also indicated that the low-cost shaker used for these measurements might be inappropriate for
the transferal of sufficient energy. Although the IR method cannot compensate for the disadvantages of the hammer method by itself, it may enable the possibility of using long and fully controllable and repeatable signals (chirp, synthetic impacts, even noise, etc.) for pile integrity testing in the future.
The present study aims to investigate the use of geopolymer mortars as passive fire protection system for steel structures. Coal fly ashes were used as aluminosilicate source and perlite was employed as aggregate to obtain a lightweight system. In addition, a geopolymer mortar containing quartz aggregate was produced for comparison. The geopolymer mortars were applied on stainless steel plates and exposed to both, cellulosic and hydrocarbon standard fire curves, according to ISO 834-1 and EN 1363-2, respectively. Acoustic emission measurements were conducted to analyze cracking phenomena during the high temperature exposure. The resulting temperature-time curves showed that the investigated system is effective in retarding the temperature rise of the steel plates. When the cellulosic fire curve was applied, a 20 mm [0.79 in.] thick layer of lightweight geopolymer mortar protected the steel substrate from reaching the critical temperature of 500 °C [932 °F] for at least 30 minutes, avoiding the rapid decrease of its mechanical properties and thus representing an important safety measure against accidental fires. No spalling phenomena on heating were detected; however, significant cracking was observed on cooling.
This contribution presents experimental methods to detect track damage. At BAM (Federal Institute of Material Research and Testing), a measuring car with a measuring system of 72 channels, geophones, mountings, cables, harmonic and impulsive exciters is used for dynamic measurements of the track, the soil and buildings. An instrumented hammer allows force measurements and to evaluate transfer functions of the track, and the soil. Wave measurements are used to identify the soil characteristics. Train passages are measured at the track and for the train induced ground vibrations. In addition to these in situ options, tests of tracks or track elements can be performed in a large laboratory.
Pigments and dyes
(2015)
The present volume is the main achievement of the Research Networking Programme ‘Comparative Oriental Manuscript Studies’, funded by the European Science Foundation in the years 2009–2014. It is the first attempt to introduce a wide audience to the entirety of the manuscript cultures of the Mediterranean East.
The chapters reflect the state of the art in such fields as codicology, palaeography, textual criticism and text editing, cataloguing, and manuscript conservation as applied to a wide array of language traditions including Arabic, Armenian, Avestan, Caucasian Albanian, Christian Palestinian Aramaic, Coptic, Ethiopic, Georgian, Greek, Hebrew, Persian, Slavonic, Syriac, and Turkish.
Seventy-seven scholars from twenty-one countries joined their efforts to produce the handbook. The resulting reference work can be recommended both to scholars and students of classical and oriental studies and to all those involved in manuscript research, digital humanities, and preservation of cultural heritage.
The volume includes maps, illustrations, indexes, and an extensive bibliography.
BACKGROUND CONTEXT: Targeted delivery of osteoinductive bone morphogenetic Proteins (eg, GDF5) in bioresorbable calcium phosphate cement (CPC), potentially suitable for vertebroplasty and kyphoplasty of osteoporotic vertebral fractures, may be required to counteract augmented local bone catabolism and to support complete bone regeneration. The biologically optimized GDF5 Mutant BB-1 may represent an attractive drug candidate for this purpose.
PURPOSE: The aim of the current study was to test an injectable, poly (l-lactide-co-glycolide) acid (PLGA) fiber-reinforced, brushite-forming CPC containing low-dose BB-1 in a sheep lumbar osteopenia model.
STUDY DESIGN/ SETTING: This is a prospective experimental animal study.
METHODS: Bone defects (diameter 5 mm) were generated in aged, osteopenic female sheep and were filled with fiber-reinforced CPC alone (L4; CPC+fibers) or with CPC containing different dosages.
Drop testing of a container for the storage. transport and disposal of intermediate level waste
(2017)
Impact tests were performed, as part of a corresponding container’s substantiation, during design development of a shielded container. The container will be used for storage, transport, and disposal of intermediate level waste in the UK.
The mechanical test program comprised a 9m free drop test onto an unyielding target in a container long lid edge down orientation at ambient conditions. Further, a 0,5m free drop test onto a punch target was performed. Here, the container was orientated with the lid downwards in a way that the punch, a mild steel bar, impacts a filter lid.
The test specimen was instrumented with strain gauges and accelerometers for the drop tests. Transient strains at selected points of the inner and outer container walls, at the shielding lid, as well as at the lid bolts were measured during the container’s impact. Furthermore, decelerations of the container body, container lid, and the skip were measured. The complex geometrical changes of the container due to impact were determined by optical 3d- deformation measures using the projected fringes method in combination with multi-image photogrammetry.
This paper summarizes the performance of the drop tests and various drop test results in context with the design development as well as aspects regarding the associated Finite Element (FE) analyses and post-test evaluation.
Our current projects focus on the material analysis of the writing materials
kept in the Taylor-Schechter Collection at Cambridge University Library,
which houses the largest collection of Cairo Geniza fragments, about 190,000.
Although Geniza manuscripts have attracted a great deal of scholarly attention,
the material aspects of these documents seem to have been largely neglected.
The current study aims to obtain information on the composition of the writing
supports and the inks that were used, the production of the original manuscripts
and the history of their degradation. The collected data should supplement the
description based on Hebrew palaeography and codicology. Moreover, a characterisation
of the writing materials would provide insights on trade, local production
techniques and social structures. The tabulated results have the potential to
be used as geo-chronological markers if sufficient data is collected.
For our study, we chose Hebrew legal documents and letters from three communities
that co-existed in Fustat (today Cairo) in the 11th century: the Jerusalemite
(or ‘Palestinian’) community, the Babylonian community and the Karaites, three
different communities with different scribal traditions. In addition to this, we
studied non-biblical scrolls attributed to the Palestinian and Babylonian communities.
The question we addressed was whether we can correlate the use of a
specific type of ink to an objective criterion.
For our analysis at Cambridge University Library, we used a number of protocols
developed at BAM (Bundesanstalt für Materialforschung und -prüfung) in
Berlin and at the Centre for Study of Manuscript Cultures, University of Hamburg
(CSMC). These include reflectographic examination followed by non-destructive
X-ray fluorescence (XRF) analysis using transportable instruments so that the
analysis can be carried out in situ.
We have illustrated our approach here by providing two examples. The first one
describes our investigation of the leather fragment containing a portion of the
Babylonian Talmud on its hair side (TS Misc.26.53.17). The second example illustrates
our ability to compare iron-gall inks using the XRF method. In this case,
we explored the question of the codicological attribution of three fragments (TS
F17.4, TS 12.755 and TS 12.756) to the same Talmud manuscript.
As part of the Qumran project conducted at the Federal Institute for Materials Research and Testing (BAM) in Berlin between 2007 and 2010, my colleagues and I developed a new, integrated methodology for determining the original and acquired properties of highly heterogeneous Dead Sea Scrolls. The purpose of this methodology is to help scholars determine the provenance of fragments of the scrolls and sort and compare them more easily than in the past. Since our measurements allowed us to differentiate between the minerals originating from the production processes and the sediments accrued during storage in the caves in Qumran, we were able to reconstruct the treatment of hides and discovered that at least two distinct parchmentproduction techniques co-existed at the beginning of the common era.
The reconstruction of workmanship on animal hides in Antiquity raised doubts about the validity of the current definition of parchment, which is based on a production technique known from the Middle Ages. We hope that our current work will also help researchers understand the characteristic properties of gewil, qelaf and dukhsustos better.¹
The evolution and socio-geographic distribution of writing inks in late Antiquity and the early Middle Ages are the second focus of our investigative work at BAM.
We use X-ray fluorescence analysis (XRF) to determine the chemical composition of inks and NIR reflectography for their typology. We are amply assisted in our ambitious enterprise by codicologists and palaeographers who have adopted our methodology and conduct field studies of their own.
In 2011, the Association of German Engineers (VDI) started working on a set of guidelines
towards increased resource efficiency. These guidelines represent a framework that defines resource efficiency and outlines considerations for the producing industry. A special guideline for SMEs is included as well as guidelines on methodologies for evaluating resource use
indicators, such as the cumulative raw material demand of products and production systems.
Resource efficiency, defined here as the relationship between a specific benefit or use and the natural resources that need to be spent or consumed to attain this benefit or use. It can be
evaluated by defining a function which expresses the specific benefit and quantifies the resource requirements through a set of indicators (use of raw materials, energy, water, land
and ecosystem services including sinks). The results from this also depend on the system boundary parameters and the allocation rules for by-products and waste treatment options. Optimising resource use is possible at all stages of a product’s or production system’s life cycle chain (raw material extraction, production and manufacturing, use and consumption, and the
end-of-life stage).
VDI guidelines are widely accepted across Germany’s industrial sector and therefore represent an important means of mainstreaming resource efficiency in this target area. As well as providing a methodological framework, the guidelines describe strategies and measures towards increasing resource efficiency, and they enable industrial producers and service providers to identify potential areas of improvement. The full article presents an overview of
the methodology and contents of these guidelines and discusses their impact in achieving absolute reductions in the industrial use of natural resources.
The International Qumran project conducted at the BAM Federal Institute for Materials Research and Testing in 2007–10 aimed at establishing an optimal methodology for an accurate characterization of the Dead Sea Scrolls to address such questions as archaeological provenance, origin, and attribution of fragments to a specific sheet (Rabin 2013). Using equipment of various degrees of complexity we have shown that part of the historic information stored in the material can be revealed by proper characterization of the material. The on-site investigation of the Dead Sea Scrolls fragments from The Schøyen Collection in October 2012 offered the first chance to test this methodology in a field study. For the first time, we used mobile and non-invasive technology exclusively, since we could not transport all of our laboratory equipment to Norway for this project. Moreover, besides the technical limitations dictated by the available equipment, we had to cope with limited time: it was impossible to perform the number of scans required for optimal characterization of over 30 fragments within the fourteen days available. Nevertheless this study presents an important step in the material analysis of the Dead Sea Scrolls, since the devices we used are easily transportable, well known, and easily accessible throughout the world.
We have obtained a minute amount of dry ink scratched from the bronze inkwell MS 1655/2. The powder was stored between two glass slides to minimize contamination. For micro analysis by FTIR a sample of the ink powder was transferred into a diamond cell while for confocal Raman spectroscopy a micro sample was placed onto sticky tape. The same portion of the sample was also investigated by scanning electron microscopy, where the elements distribution was determined by EDX.
The aim of our work was to check whether the assumption that the jar was discovered in Qumran can be substantiated. In order to establish the archaeological provenance of the jar we conducted a series of analytical tests on samples of material collected from the jar in April and June 2009. The samples were either found loose within the jar, these being probably constituted by remnants of its original contents, or were clay detached from the inner and outer surface of the jar. In addition, a portion of sand deposit coating the inside of the jar handles was analysed.
In the field of modelling hydrogen assisted cracking (HAC) phenomenon, hydrogen diffusivity is an important input parameter for numerical simulation. In terms of hydrogen diffusion coefficients, they have great impact on realistic assessment of the evolution of possible crack critical hydrogen concentrations. In addition, the chemical compositions of steels can have a strong effect on hydrogen diffusion. Unfortunately, literature provides a wide range of available hydrogen diffusion coefficients even for similar microstructures and equal temperatures. The scattering of the data can lead to significant deviations in the results of simulating the evolving hydrogen concentrations due to hydrogen uptake (by fabrication or service). Thus, the application of such data to crack-models or for component life tie predictions can be realized up to the present only by considering envelope curves of such value, corresponding to a work or bench case scenario, respectively. For improved reliability of numerical simulaitons, it is necessary to minimize the mentioned deviation of these data. Hence, this work focuses on the validation of hydrogen diffusion coefficients obtained from permeation experiments at room temperature. Two baintic steels with different alloying concepts were investigated, the creep-resistant 7CrMoVTiB10-10 and the reactor pressure vessel grade 20MnMoNi4-5. A numerical model is presented for simulation of the corresponding hydrogen diffusion during permeation experiments using the finite element software ANSYS. Three different diffusion coefficients (obtained from different common calculation methods) are considered and compared to numerical results. The vases of thes calculation methods are permeation transients which are a direct measure for hydrogen. The results of the simulated hydrogen diffusion coefficients show that only one procedure for calculation of diffusion coefficitnes is suitable in comparision to the experimental values. Thus, it is suggested to use this method for analysis of experimental results in case of hydrogen diffusion during permeation experiments. Furthermore, this work supplies validated values for the hydrogen diffusion coefficients of both steel grades.
The program PowderCell is a crystallographic tool for visualization of Crystal structures. However, it offers also non-conventional features like the fulautomatical generation of subgroups or the consideration of non-standard settings of space-group types. On the one Hand the program is very useful for non-crystallographers who like to get an impression of the atomic arrangement within the unit cell. But also for crystallographers it is recommendable because it contains a lot of additional information which can be extracted and used like data given in the International Tables for Crystallography, Vol. A. However, the most important advantage of the program is the simultaneous calculation of the X-ray or neutron diffraction powder patterns for a mixture of up to 10 crystalline phases. Between more than 7 different characteristic radiations can be chosen and their influence on the resulting powder pattern can be studied. Furthermore, experimental diffractograms can be analysed using a refinement procedure. The implemented LeBail-algorithm allows the investigation of unknown phases. In combination with the refinement algorithm an interface to Shelx offers the possibility for a step by step ab initio structure analysis. Certainly, the user-friendly shell is one reason that especially users who are not so familar with space-group symmetry, crystal structure data or diffractometry use this powerful tool for the solution of scientific or analytical problems as well as in teaching.
X-ray stress analysis on crystalline materials is based on the determination of elastic lattice strains. The strains described by the shift of peak positions are converted to stresses by the means of theory of elasticity. The development of the sin2ψ-method of X-ray stress analysis introduced an enormous progress in X-ray stress analysis during the last decades. This report outlines some important elements of X-ray physics and fundamentals of theory of elasticity. The Standard measuring procedure are described and special experimental differences to the common powder diffractometry are outlined.
In context with Japanese disposal and transport container safety assessment the German Federal Institute for Materials Research and Testing (Bundesanstalt für Materialforschung und -prüfung) per-formed extensive drop test series with prototypes of RAM packages in recent years.
The paper presents two cooperative projects focused on project management, testing performance and experimental results.
In the first project, a full-scale prototype of a package for transport and storage of spent fuel elements with a total mass of 127,000 kg and its reduced-scale model which was similar to the prototype in both geometry and design were drop tested in 9 m and 1 m puncture tests at various drop orientations under regulatory conditions. In context with a corresponding research project the test data was used in combination with numerical methods to investigate the phenomenon of internal cask- content collisions during drop tests. Here, technological gaps between basket or radioactive content and cask body or primary lid can be a reason for significant high dynamic loadings of cask components and its internals due to additional impact interactions in the cask cavity caused by inner relative movement between content and cask. Further investigations were carried out in the field of similarity mechanics comparing experimental drop test data of the full-scale prototype and reduced-scale model in regard to the transferability of package impact response from reduced-scale models to full-scale packages.
In the second project, drop tests with a waste container for intermediate depth disposal were per-formed being contracted by Kobe Steel, Ltd. and a consortium of Japanese electric power plant com-panies. The drop test program comprised three single 8-m drop tests in a specimen’s corner edge orientation. For drop tests according to legal regulations for interim storage or final disposal it is often necessary to use a target which represents the real ground of the storage facility. In such cases the container hits directly onto a well-defined concrete slab on top of the IAEA target. Here, the directly impact target for the drop tests were concrete slabs manufactured in Japan and connected by mortar to the impact pad of the unyielding IAEA target.
Reactive geomembranes and geotextiles are an innovative approach to control the migration of contaminants in geotechnical applications. Within a joint research project in cooperation with a medium-sized enterprise, the preparation and characterization of “reactive” geomembranes and geotextiles modified by the addition of zero-valent metal nanoparticles was performed. Zero-valent iron (ZVI) nanoparticles were added to polyethylene or to the fillings of geo-containers or geosynthetic clay liners. These geosynthetic products consist of mixtures of sand with clay or bentonite, typically embedded in geotextile nonwovens or geomats. The permeability of these geo-containers can be adjusted by the ratio of clay or bentonite to sand. ZVI nanoparticles were also added as reactive material to geomembranes made of polyethylene with additives like the antioxidant Irganox 1010 or glycerin. These additives prohibit oxidation of the nanoparticle and act as hydrogen donor in the dechlorination of chlorinated hydrocarbons. Contaminates such as chlorinated hydrocarbons and toxic heavy metal compounds are either decomposed or converted to less toxic species (e.g. Cr-(VI) reduction to Cr-(III)). The paper reports the first experimental results from manufacturing of the reactive geomembrane model materials and characterization of the products with microscopic techniques. First breakthrough measurements of the ZVI modified geomembrane compared to a reference sample are presented.
A biological impact on weathering was recognized already at the beginning of the twentieth century, when biochemical influence of the lichen growth on rocks was convincingly demonstrated. Later it was shown that the
progress of solid rock weathering initiated by biological colonization was affected by the initial porosity system and sensitivity of mineral association. In the meantime
a considerable amount of diverse scientific data confirm the importance of biological rock colonizers (lichens and free-living rock biofilms) in mineral material dynamics as they occur at the atmosphere-exposed rock surfaces on local as well as global scale. Subaerial rock biofilms—microbial ecosystem including free-living heterotrophic and phototrophic settlers of bare rock surfaces—are characteristic for the first stage of primary succession of terrestrial ecosystems on mineral substrates.
These cultivable and free-living communities are dominated by fungi and set the stage for the later development of a lichen cover, but in comparison to lichens also represent a new tool for laboratory experimentation and thus open a new stage of work in geomicrobiology. The Minerals sensitivity to microbially induced biological weathering can be demonstrated by studies of natural samples as well as by the laboratory mesocosm experiments.
Hydrogen assisted stress corrosion and cold cracking represent still a major topic regarding the safety of welded steel components against failure in many industrial branches. Hydrogen might be introduced during fabrication welding or might be taken up from an environment during sour service or at cathodic protection. Additionally, understanding and avoidance of hydrogen entry into weld microstructures from gaseous pressurized environments becomes increasingly important for renewable energy components. There are two types of metallurgical mechanisms associated with hydrogen assisted cracking, i.e. the cracking as well as hydrogen transport and trapping mechanisms. For numerical modelling, it has to be considered that both types are not independent of each other, that the mechanisms are not yet completely clarified and that validation of such models strongly depends on implementation of the correct hydrogen related materials properties. However, quite significant achievements have been made in modelling of hydrogen assisted cracking by indirect coupling of thermal, stress-strain as well as hydrogen uptake and diffusion analyses. After a brief introduction into the subject and by revisiting various proposed cracking mechanisms, the present contribution focuses on recent developments of a numerical model based on a comparison of actual hydrogen concentrations and mechanical loads with respective hydrogen dependent material properties as crack initiation and propagation criteria. The basic procedure for numerical simulation of crack initiation and propagation is outlined and it is shown how such numerical simulations can be validated experimentally. Furthermore, it is highlighted how such a procedure has been extended to a comprehensive model for life time prediction of welded steel pipeline components and experimentally verified. Finally, it is outlined how the model can be extended to simulate cracking in heterogeneous steel microstructures on the different scales.
Since the mid-nineties, supermartensitic stainless steels (SMSS) have increasingly been applied to welded subsea-pipeline systems in the North Sea oil and gas fields, especially to flowlines at mild sour service conditions. However, in 2001 cracking and leaks occurred during installation and service start-up of two SMSS flowlines in the Norwegian Tune gas condensate field, welded with a new developed matching filler wire. Brittle transgranular cracking started especially at inter-run lack of fusion and propagated brittle, predominantly through the weld metal. The present paper provides a brief overview of the original failure case and respective sequence of events leading to complete replacement of the SMSS by carbon steel flowlines in 2002. Then, detailed investigations of a circumferential weld sample of the failed Tune flowline are highlighted, targeted at comparison of the failure appearance to previous investigations of this filler material type and to search for possible explanations for the brittle fracture at the crack initiation area. SEM investigations of the fracture surface revealed brittle areas only in the direction towards the top side of the weld while the major part of the investigated surface exhibited ductile fracture. As an approach to clarify, if the fracture was a consequence of hydrogen assisted cracking, five small sized specimens have been cut out of the original sample. Cracking has been introduced parallel to the original fracture surface in these specimens at respective saw cuts and bending. The results show that brittle transgranular cracking appeared only in the specimen cooled down to very low temperatures by liquid nitrogen and in the sample charged with hydrogen to an average concentration of about 15 ml/100 g. However, a fracture similar to the original surface was observed only in the hydrogenized specimen. As a further result, very similar fracture surfaces of supermartensitic stainless steel weld metals had been observed on specimens subjected to hydrogen assisted cold cracking (HACC) as well as to hydrogen assisted stress corrosion cracking (HASCC). In total, the results indicate that brittle fracture starting at the inter-run lack of fusion were not initiated by high notch tip deformation rates, but rather influenced by hydrogen, probably taken up during welding.
Numerical investigations on hydrogen-assisted cracking in duplex stainless steel microstructures
(2016)
Duplex stainless steels (DSS) are used in various industrial applications, e.g. in offshore constructions as well as in chemical industry. DSS reach higher strength than commercial austenitic stainless steels at still acceptable ductility. Additionally, they exhibit an improved corrosion resistance against pitting corrosion and corrosion cracking in harsh environments. Nevertheless, at specific conditions, as for instance arc welding, cathodic protection or exposure to sour service environments, such materials can take up hydrogen which may cause significant property degradation particularly in terms of ductility losses which, in turn, may entail hydrogen-assisted cracking (HAC). The cracking mechanism in DSS is different from steels having only a single phase, because hydrogen diffusion, stress-strain distribution and crack propagation are different in the austenite or ferrite phase. Therefore, the mechanism of HAC initiation and propagation as well as hydrogen trapping in DSS have not been fully clarified up to the present, as for most of the two-phase microstructures. At this point the numerical simulation can bridge the gap to a better insight in the cracking mechanism regarding the stress-strain distribution as well as hydrogen distribution between the phases, both austenite and ferrite, of the DSS. For that purpose, a two dimensional numerical mesoscale model was created representing the microstructure of the duplex stainless steel 1.4462, consisting of approximately equal portions of austenite and ferrite. Hydrogen assisted cracking was simulated considering stresses and strains as well as hydrogen concentration in both phases. Regarding the mechanical properties of austenite and ferrite different statements can be found in the literature, dependent on chemical composition and thermal treatment. Thus, various stress-strain curves were applied for austenite and ferrite simulating the HAC process in the DSS microstructure. By using the element elimination technique crack critical areas can be identified in both phases of the DSS regarding the local hydrogen concentration and the local mechanical load. The results clearly show different cracking behavior with varying mechanical properties of austenite and ferrite. Comparison of the results of the numerical simulation to those of experimental investigations on DSS will improve understanding of the HAC process in two phase microstructures.
In this paper we present the results of imaging studies of ancient Egyptian metallic artifacts using micro-Computed Tomography (micro-CT). Micro-CT is a non-destructive imaging method with high spatial resolution, which enables the examination of the internal structure of objects. It is thus especially suitable for the investigation of cultural heritage and archaeological findings, when it is not possible to sample or difficult to manipulate the object. Using specialized software for 3D visualization and segmentation, data sets of two objects were analyzed. We gained a clear view of the inner structure of a metallic archaeological artifact from the necropolis of Abusir el-Meleq, which is believed to be very ancient in the Egyptian archaeological context (from the Predynastic Era), and were able to distinguish its different omponents under the thick layers of external concretions. These components give hints about the production technology of the object. We also investigated the contents of a closed metal box found near Abusir dated to the Late/Greco-Roman Period. The identified Content corresponds either to sediments or to mineral remains of the original content of the box. Both artifacts are from excavations conducted in Egypt and are part of the archeological collection of the Ägyptisches Museum und Papyrussammlung in Berlin.
Duplex stainless steels have been used for a long time in the offshore industry, since they have higher strength than conventional austenitic stainless steels and they exhibit a better ductility as well as an improved corrosion resistance in harsh environments compared to ferritic stainless steels. However, despite these good properties the literature shows some failure cases of duplex stainless steels in which hydrogen plays a crucial role for the cause of the damage. Numerical simulations can give a significant contribution in clarifying the damage mechanisms. Therefore, a numerical model of a duplex stainless steel microstructure was developed enabling simulation of crack initiation and propagation in both phases. The phase specific stress strain analysis revealed that local plastic deformation occurs in both austenite and δ-ferrite already in the macroscopically elastic range. Altogether, phase specific hydrogen-assisted material damage was simulated for the first time taking into account all main factors influencing hydrogen assisted cracking process. The results agree well with experimental observations and thus allow a better insight in the mechanism of hydrogen-assisted material damage.
Properties of pipe steels for CCS technology require resistance against the corrosive environment of a potential CCS-site (heat, pressure, salinity of the aquifer, CO2-partial pressure). The influence of austenitizing in heat treatment routines of two different injection pipe steels (1.4034, X46Cr13 and 1.4021, X20Cr13) was evaluated. Steel coupons were austenitized at different temperatures (900 – 1050 °C) for different lengths of time (30–90 min) before quenching and annealing prior to long term corrosion experiments (60°C, 100 bar, artificial brine close to a CCS-site in the Northern German Basin, Germany). In general, fewer pits are found on X46Cr13. Comparing steels with 13% chromium each the higher carbon content of X46Cr13 (0.46% C) results in a lower number of pits compared to X20Cr13 (0.20% C). It is found that neither the carbon content of the steels nor austenitizing temperature has much influence, but local corrosion behaviour is most susceptible towards austenitizing time
As a chemical metrology tool time-of-flight secondary ion mass spectrometry (ToF-SIMS) has become a very popular technique to monitor the elemental, isotopic and molecular distribution in two or three dimensions. Its reduced sampling depth, high sensitivity, great structural specificity and the direct detection of hydrogen thereby increase the emergence of ToF-SIMS for material and analytical surface science, particularly due to recent instrumental developments improving mass, depth and lateral resolution. For basic surface science, adsorption processes and surface reactivity thus can be investigated in high detail on organic as well as inorganic samples. The use of multivariate data analysis in addition can effectively assist to identify trends in the complex SIMS raw data set and define key co-variances between certain samples or mass spectra. In this contribution the essence of ToF-SIMS is illustrated by discussing two highly relevant energy applications. First, for piezoelectric electroceramics oxygen exchange active zones have been visualized to determine the impact of external field-load to the oxygen vacancy distribution between anode and cathode. As a second case study the interaction of hydrogen species with the microstructure of a duplex stainless steel was investigated. It was concluded that ToF-SIMS has a valuable essence for detailing hydrogen related degradation mechanisms.
Bottom ash from municipal solid waste incineration (MSWI) consists of eiemental metals in considerable amounts. The fine fraction < 4 mm additionally contains chemically bound metals (oxides, carbonates, Silicates). Separation prospects with techniques as in ore processing (flotation, density separation, bioleaching, hydrothermal solution) are discussed. During alteration after wet extraction mineral material with hydraulic properties form coatings on almost all particles of the bottom ash and complicate separation procedures. ln addition bottom ash from MSWI is a heterogeneaus material. For sufficient enrichment different concerted treatment steps seemed to be essential associated with an uncertainty of economic viability. The utilisation of metal compounds present in bottom ash as secondary raw material depends on the energy- and resource-efficiency of the enrichment processes. Therefore energy and material flow considerations are presented.
To resist the corrosive geothermal environment during carbon capture and storage CCS -such as: heat, pressure, salinity of the aquifer, CO2-partial pressure, properties of pipe steels-require certain specification. For evaluation samples of differently heat treated high alloyed stainless injection-pipe steels AISI 420 X46Cr13, AISI 420J X20Cr13 as well as X5CrNiCuNb16–4 AISI 630 were kept at T=60 °C and ambient pressure as well as p=100 bar for 700 h up to 8000 h in a CO2-saturated synthetic aquifer environment similar to a possible geological situation in the northern German Basin. Corrosion rates and scale growth are lowest after long term exposure for steels hardened and tempered at 600 °C to 670 °C and pits -indicating local corrosion- decrease in diameter but increase in number as a function of carbon content of the steel. Martensitic microstructure is preferred with respect to these particular conditions.
More information about the capability and especially about the durability of structural sealant glazing (SSG) systems are needed. To make a contribution to unanswered questions, a suitable system evaluation test is necessary. The basis for such a test is a load function, which accounts for the decisive loads SSG systems are exposed to during their working life. This paper proposes a general load function for standard SSG systems at central German locations for accelerated durability tests. Decisive loads are determined and different SSG construction types defined. The performance of these SSG systems under exposure to external loads and to a dynamic pendulum impact is investigated via finite element analyses using a hyperelastic material model. The external loads are applied separately and superimposed. Compression, tensile, and shear deformations of the sealant are determined. It is found that the sealant is subjected to normal and shear stresses simultaneously. The requirements for a representative specimen are derived. The results will be taken as basics for the development and the construction of a test facility to evaluate the durability of structural sealant glazing systems.
Structural sealant glazing (SSG) is an impressive technical response to the challenges of modern structural design. The evaluation of fitness for use as well as durability is a precondition for approval of SSG-façades by building authorities because of their special safety relevance. However, the potential of the actual evaluation methodology to reproduce performance as well as durability under real use conditions is generally assessed to be limited. The concept so far is criticized as mainly single-loading and incomplete in comparison to the real use conditions. The exercised separation of the in reality interacting loading effects is assessed as insufficient and inadequate to explore performance. Consequently, the performance and capability of SSG-solutions is only fragmentarily explored. However, the most restricting argument so far is the deficit of the actual test methodology for life cycle prognosis under interacting mechanical as well as climatic loads. Because of the limited acceptance, additional structural design conditions are imposed by the authorities. Besides this restriction, there is also an increasing demand by the authorities, architects, and users for determinable working life cycles, not least under economic aspects. That is why knowledge, particularly regarding SSG-performance and durability, must be expanded. Together with partners representing all branches involved in façade engineering (engineering design, sealant producer, applicator, and cladding company) the Federal Institute for Materials Research and Testing (BAM) develops a new system test focused on the substrate–sealant–glass panel interaction. With it, a new comprehensive dynamic–mechanical evaluation methodology already introduced at the fourth Symposium in Anaheim, CA, in 2011 shall be complemented by a performance-related system test. Subject-matter of this contribution is the presentation of a new dynamic–mechanical system test method and its first experimental application on SSG-systems. We describe our approach beginning with the discussion of relevant load effects on sealant joints and with the help of a highly generalized finite element (FE) analysis. Resulting from a parameter study of various load combinations acting on different SSG-construction types, we derive a practicable deformation load function from the decisive load categories taking into account regular as well as extraordinary loads. Assumptions and procedures to quantify their parameter values (regarding the effective direction and order of deformation magnitude affecting the substrate–sealant–glass bond) are discussed. The calculated decisive sealant deformations resulting from the parameter study are validated by simplified mechanical plausibility tests. Subsequently, the transfer of the findings about the substrate–sealant–glass panel bond loading into the design and construction of an adapted system test specimen and the development of a multifunctional test facility is introduced. The multi-functional applicability of the system test device is discussed. On the basis of results during our actual operational checks, first ideas about system performance and durability under superimposed loading are presented. A validation of this new test methodology by comparison to test results of disassembled samples and in situ results is a task for separate research activities.
Monitoring of cracks in historic concrete structures using optical, thermal and acoustical methods
(2015)
Cracks are a major issue in the field of cultural heritage. In order to evaluate the significance of a crack, a long term monitoring of the damaged region is required. However, there is a lack of easy to operate tools for such monitoring measures. Therefore, new or existing methods for other applications have to be optimised for cultural heritage investigation. The paper describes the application of such crack observation methods on a historic concrete sculpture. Beside conventional methods, like mapping by hand and ultrasonic depth profiling, a novel tracking system is presented. Furthermore, the suitability of active thermography for the investigation of cracks was investigated. The results show promising prospects for these non-destructive techniques.
Evaluation of an interlaboratory comparison of the chemical assay of U, Th oxide coated particles
(1981)
The risk assessment of total petrol hydrocarbons (TPH) and polycyclic aromatic hydrocarbons (PAH), two of the most frequent soil and water contaminants, has to include their exposure pathways, especially the soil groundwater pathway. Threshold values have to be aquired for the amendment to the German Federal Soil Protection Contaminated Sites Ordinance. For this purpose, a batch experiment with a liquid to solid ratio (L/S) of 2 L/kg was developed. Aim of this work was to verify the robustness of this leaching procedure for TPH and PAH in different soil types against varying test conditions. Also, stir bar sorptive extraction (SBSE) was tested as alternative sample preparation of eluates for PAH analysis.
The inevitable increase of torque or load, because of lightweight approaches, pushes the oil-film temperatures on the teeth flanks of gears above 200°C, and requires alloys with higher strength and toughness properties. Furthermore, the real temperature on surfaces during the physical vapor deposition (PVD) or chemical vapor deposition (CVD) of thin films can exceed the annealing temperature of the state-of-the-art bearing and gear materials, such as AISI 52100 (1.3505), 16MnCr5 (1.7131), 21NiCrMo (1.6523), and 30CrMoV9 (1.7707). Such trends call for slip-rolling-resistant, alternative alloys suited for contact stresses above P0max of >2.2 GPa. The tribological profile under slip-rolling conditions at 120°C in a factory engine oil (SAE 0W-30, ACEA A3/B4, ν120°C = 5.33 mPa, HTHS150°C = 3.0 mPa) until 10 × 106 load cycles between P0max of 2.25 GPa to 3.92 GPa of uncoated 100Cr6 (1.3505, PBQ), 102Cr6 (1.2067), Cronidur 30 (1.4108, DESU), 45SiCrMo6 (1.8062, CVEM), 40SiNiCrMo1 [vacuum arc remelting (VAR)], CSS-42L (AMS 5932, vacuum induction melting (VIM)-VAR, and carburized), 36NiCrMoV1-5-7 (CAB), ASP2012 (ASP), and 20MnCr5 (1.7131, carburized) was established in twin disk machines (Amsler-type and 2Disk). The present benchmark illuminates the tribological impact of uncoated bearing steels in comparison to uncoated alternative steel alloys on friction, wear and slip-rolling resistance, as well as load carrying capacity. Iron-based steel alloyed with silicon or molybdenum reduces alloying costs and avoids thermo-chemical treatments. This benchmark suggests considering an extension to fracture toughness from hardness and strength as a relevant property for slip-rolling alloys. If slip-rolling resistant, the wear rates of the metallurgical different steels were more or less within one order of magnitude, but the influence of increasing contact stresses on the tribological profile differed significantly.
The use of open GIS standards offers a broad variety of potential, particularly in the field of data exchange, data storage, and interoperability. GML and CityGML are excellent examples for the ontological description of real world objects by means of an open standard whereas SensorML serves to describe measurements, sensors and measuring platforms. The use of such standards offers not only the possibility of using a common standardised language, but also the use of open service standards. The combination of spatial data and sensor standards in services and service-oriented architectures goes far beyond previous existing solutions on the market and provides a novel platform for monitoring structures. That in fact is far more than a simple data storage model. The methods and models presented in this contribution allow a direct integration of sensor data and its provision through an open standard language. In this case, all the intermediate steps at any time through an open service interface are addressed and may be made available and provided to different actors and stakeholders participating in a construction scenario. The great potential and the added value of such an information system is the permanent availability of measurement and object data and an associated integrated analysis of sensor data in combination with a finite element model (FEM). The automatic derivation of a finite element model from the 3D structure model, the visualisation of FEM, the provision of raw (measurement) data and sensor information for each time of measurement transform the platform into a universal tool in the field of structural monitoring. This contribution introduces the individual components, the standards used and the interaction between the components to an overall system.
Quantitative online NMR spectroscopy of technical mixtures: on the fly quantification of fluids
(2014)
In this paper quantitative NMR spectroscopy is demonstrated as a tool for process analytical technology (PAT) in order to obtain real time information from dynamic processes. Different methods for quantification are presented and as a result the limit of detection for NMR measurement could be determined to 3.3 mg kg-1 (ethanol in water). As model processes esterification reactions and dissolution of pharmaceutical formulations are presented and important process parameters are extracted. Furthermore it is demonstrated that not only 1H-NMR spectroscopy can be used for process monitoring but also 13C-NMR for technical mixtures.
Characterization of randomly branched polymers utilizing liquid chromatography and mass spectrometry
(2014)
Branching in polymers is an important way to modify the materials properties, however the characterization of random branching in polymeric materials is a challenge in polymer analysis. In this work, liquid adsorption chromatography methods are developed for a commercially available hyperbranched polyester (Boltorn™). This Chromatographie techniques was then coupled to offline MALDI-TOF MS analysis, a first in the analysis of randomly branched polymers. The coupling of these two techniques provides superior MALDI-TOF spectra, enabling the easy identification of structural subdistributons based on theoretical molecular weight. Detailed analysis of the MALDI-TOF spectra shows that these Chromatographie conditions separate cyclic Boltorn polymers (with no core molecule) from non-cyclic polymers (with core molecule), and these are the only two architectures observed. MALDI MS also confirms that the Chromatographie Separation mode is adsorption, but further analysis is needed to determine if there is a Separation by degree of branching.
The ground vibrations, which are generated by trains on different tracks, have been calculated by finite-element boundary-element models. The ballasted track is modelled in detail by the finite element method. The infinite soil is modelled by the boundary element method as a homogeneous or layered half-space. The track-soil system is coupled to a simple rigid mass model of the vehicle so that the vehicle-track interaction is completely included. Transfer functions are calculated in frequency domain without and with vehicle-track interaction, the compliance of the track and the mobilities of the soil at different distances from the track. Finally, the ratios between the ground vibration amplitudes with and without mitigation measures are calculated to quantify the effectiveness of the mitigation measures.
Tracks with under-sleeper pads have been investigated in a wide parameter study for the RIVAS project. The main parameters that influence the reduction of ground vibration are the stiffness of the under-sleeper pad, the mass and the width of the sleeper. The softest sleeper pad yields the best reduction of the ground vibration. The influence of the sleeper mass is not so strong, as the characteristic frequency is ruled by the mass of the sleeper and the mass of the wheelset as well.
For the accuracy of inertial navigation systems for indoor localization it is important to get high quality sensor data of the multi-sensor system. This can be realized using high quality sensors or the developed 3D-self-calibration-method for low cost sensors. Based on the calibration procedure of the accelerometer (ACC) and the magnetic field sensor (MAG), the additional integration of the gyroscope (GYRO) leads to a reduction of the indoor positioning error. This improves both the approximation for the accelerometer, the magnetic field sensor and the gyroscope so that the standard deviation of a single sensor is minimized. There are errors in the whole system. To determine these error sources it is important to define the measurement uncertainty. In this paper it is presented that the measurement uncertainty can be reduced by the application of the developed 3D-self-calibration method.
The efficiency of wood gasification can be improved by applying membrane based gas separation operations in several of its sub-processes. In the present study the use of membranes made of hardened cement pastes for this purpose was investigated to provide a low cost alternative to conventional membrane materials. The pastes were tested for their diffusional properties in a Wicke-Kallenbach cell and analyzed with regard to their pore structure. The use of low water to binder ratios and slag and/or pozzolans led to a finer pore structure and higher separation factors; in particular, an approximately linear dependence of the separation factors on the threshold radii was observed. The results implicated that Knudsen diffusion is the prevailing diffusion mechanism in the membranes. Deviations from the theoretically expected separation factors were found, which may be ascribed to concentration polarization and channeling effects.
The selective compression of quick response (QR) and Data Matrix code carriers based on shape memory polymer (SMP) with a freely configurable steel ball type indenter and adjacent thermo-mechanical shape fixing gave notched, room temperature (23 °C) stable, temporary shapes with non-decipherable codes. The microscopic investigation of cryomicrotome sections unveiled indentation-related shape fixities of about 90 %. Independent of the selected two-dimensional code, the triggering of the SM effect resulted in sufficient shape recoveries to restore the code readability so that a maximum number of characters including 122 for a QR code (version 7) and 112 in case of a Data Matrix code (version 12) could be read with a scanning and decoding device. Due to the large number of difficult to copy shapes with on demand releasable information, SMPs may serve as viable information carriers for product and brand protection applications.
Hydrogen embrittlement (HE) is a widely known phenomenon and under investigation already for more than a century. This phenomenon, though thoroughly studied, is not yet completely understood, and so far, there are several suggested mechanisms that try to explain the occurrence of HE. One important factor of understanding the HE phenomenon and predicting hydrogen-assisted failure is the descent knowledge about the hydrogen transport behaviour in the material. Neutron radiography is a proven method for tracking hydrogen diffusion and it was applied successfully in various research studies. In the presented study, we examined the hydrogen effusion behaviour in duplex stainless steel by means of neutron radiography and calculated the effective diffusion coefficient from the obtained transmission images.
High strength structural steels are susceptible to hydrogen embrittlement. A critical combination of stress, amount of diffusible hydrogen and microstructure is believed to cause cold cracking. Especially during welding of high strength structural steels high tensile residual stresses may develop. Therefore, a feasibility study was conducted using synchrotron X-ray diffraction in order to analyze the stress–strain behavior during tensile loading. For that purpose two types of steel showing different hardening mechanisms were used. On the one hand a thermo-mechanically treated S1100MC and on the other hand a quenched and tempered S1300Q were chosen. The samples were electrochemically charged with hydrogen and subsequently stored in liquid nitrogen to prevent effusion. Tensile tests of the samples were conducted in a special load frame allowing for tilting the samples while applying constant loads. High energy synchrotron radiation was used for energy dispersive X-ray diffraction (EDXRD) analysis in transmission geometry. This method offers the possibility for measuring several diffraction lines of all contributing crystalline phases of the material. Strains as well as stresses applying the sin²ψ-method were determined for varying load situations. This feasibility study shows how the interaction of hydrogen and the stress/strain response may be assessed by diffraction methods. Examples are presented showing that hydrogen alters the load distribution as well as the strain behavior between different lattice planes in high strength steels.
As more offshore wind parks are commissioned, the focus will inevitably shift from a planning, construction, and warranty focus to an operation, maintenance, and investment payback focus. In this latter case, both short-term risks associated with wind turbine component assemblies, and long-term risks related to integrity of the support structure, are highly important. This research focuses on the role of condition monitoring to lower costs and risks associated with short-term reliability and long-term asset integrity. This enables comparative estimates of the life cycle costs and reduction in uncertainty, both of which are of value to investors.
The glass transition behavior of ultra-thin supported polymer films is discussed controversially in the literature for around 20 years. Substantial efforts have been archived to understand it. In this contribution, a combination of methods sensitive to bulk properties of a system, like dielectric or specific heat spectroscopy with surface analytics, for instance, atomic force microscopy (AFM), contact angle measurements, and X-ray photoelectron spectroscopy (XPS) were employed to study the glass transition of ultra-thin supported films. All investigations were carried out on identically prepared and treated samples. Different systems with different complexities going from more or less flexible homopolymers over rigid main chain macromolecules to polymer blends have been studied. For the investigated flexible macromolecules, the dynamic glass transition temperature estimated within the frame of the linear response approach is independent of the film thickness down to several nanometers and identical to the bulk value. For polystyrene it was found the thermal glass transition temperatures can depend on the film thickness. This different behavior is not well understood till now and needs further experimental clarification. For the investigated main chain polymers polycarbonate and polysulfone. Dynamic and thermal glass transition temperature estimated from the dielectric measurements increases with decreasing film thickness. This is discussed in the frame of a strong interaction of the polymer segments with the surface of the substrate. In general for homopolymers, the interaction energy of the polymer segments with the substrate surface cannot be considered as the only parameter, which is responsible for the change in the thermal glass transition with the film thickness. For the investigated miscible blend system of polystyrene/poly(vinyl methyl ether) at a composition of 50/50 wt-% a decrease of the dynamic glass transition temperature with decreasing film thickness is found. This is explained by the formation of a poly(vinyl methyl ether)-rich surface layer with a higher molecular mobility.
Wear
(2014)
Original equipment manufacturers (OEMs) and end-users perceive “wear” or “oil drain” differently. Spare parts, Services, and accessories contribute to an important portion to the profit of the OEMs. Maintenance and shutdowns define the operational costs of end-users. Thus, the strategy in order to exploit “wear” depends from the market structure and is up to the reader and/or applicant. The topic “Service Life/Durability/Life Cycle” represents a very ambiguous one and was already thematized in earlier times.
Tribosystems
(2014)
A tribosystem is an entity with a structure of interacting components in relative motion to perform a technical function.
Note 1 Function and structure of tribosystems may be detrimentally influenced by frictioninduced energy dissipation and wear-induced materials degradation.
Note 2 Friction and wear in tribosystems can be mitigated by lubricants and lubrication.
Stribeck curve
(2014)
The importance of lubricants in virtually all fields of the engineering industry is reflected by an increasing scientific research of the basic principles. Energy efficiency and material saving are just two core objectives of the employment of high-tech lubricants. The encyclopedia presents a comprehensive overview of the current state of knowledge in the realm of lubrication. All the aspects of fundamental data, underlying concepts and use cases, as well as theoretical research and last but not least terminology are covered in hundreds of essays and definitions, authored by experts in their respective fields, from industry and academic institutes.
Polyalkyleneglycols are oxygen containing base oils, which enable a) polymer-free formulations with high intrinsic viscosity indices favorable for fuel economy, b) bio-no-tox properties and c) low viscosity formulations with low evaporaions. The oxygen present in each monomer of the backbone of polyalkylene glycols defines intrinsic properties, such as high viscosity indices, low NOACK-evaporation, extreme pressure, high hear capacities, etc., thus enabling metal-, ash- and polymer-free engine oil formulations supporting the functional benefits, such as improved of fuel economy or no adverse effects on after-treatment devices.
Fretting
(2014)
The importance of lubricants in virtually all fields of the engineering industry is reflected by an increasing scientific research of the basic principles. Energy efficiency and material saving are just two core objectives of the employment of high-tech lubricants. The encyclopedia presents a comprehensive overview of the current state of knowledge in the realm of lubrication. All the aspects of fundamental data, underlying concepts and use cases, as well as theoretical research and last but not least terminology are covered in hundreds of essays and definitions, authored by experts in their respective fields, from industry and academic institutes.
Coatings for slip-rolling
(2014)
This paper provides an overview about state of the art methods in the field of plasma spectrometry and its application in material science. Different types of plasmas with their special characteristics for various applications are described. Indirect analytical methods involving sample digestion and often also analyte/matrix separation prior to analyzing the samples still represent the most important routine methods. Here, plasma optical emission and mass spectrometry are the most frequently used determination techniques with a wide variety of instruments commercially available. To avoid the risk of analyte loss or of contaminations during an often time consuming and laborious sample preparation, the use of techniques with direct solid sampling is considered an attractive alternative for the analysis of many materials. A survey on applications with a special focus on direct solid sampling techniques such as GDMS, GD-OES, LA-ICPMS, ETV-ICPMS, ETV-ICP-OES, DC-Arc is given. Different possible calibration strategies are discussed.
This review gives representative examples of the various types of synthetic cationic polymers or polyampholytes (chemical structure, architecture, etc) that can be used to complex DNA (forming polyplexes) for their application in gene delivery. In designing polycations for gene delivery, one has to take into account a balance between protection of DNA versus loss of efficiency for DNA condensation and efficient condensation versus hindering of DNA release. Indeed, if the polyplexes are not stable enough, premature dissociation will occur before delivery of the genetic material at the desired place, resulting in low transfection efficiency; on the other hand, a complex that is too stable will not release the DNA, also resulting in low gene expression. The techniques generally used to determine these properties are gel electrophoresis to test the DNA/polymer complexation, ethidium bromide or polyanion displacement to test the affinity of a polymer for DNA, and light scattering to determine the extent of DNA condensation. Moreover, with the development of more precise instruments for physico-chemical characterization and appropriate biochemical and biophysical techniques, a direct link between the physico-chemical characteristics of the polyplexes and their in vitro and in vivo properties can be drawn, thus allowing tremendous progress in the quest towards application of polyplexes for gene therapy, beyond the research laboratory.
Basic principles and technical realization of Auger Electron Spectroscopy (AES) are presented. Different modes of application are briefly addressed. These are spectroscopy at nanoscaled surface layers including quantitative element analysis and chemical state analysis, in-depth element analysis, imaging and element mapping. A survey on standards related to application of AES in surface chemical analysis is given.
Glossary Biomineralization A process by which living organisms produce minerals. - Chernobyl Ukrainian city site of the largest nuclear power plant accident in history. - Cut-off-wall Underground structure designed to prevent the flow of water. - DART Deep aquifer remediation tool. - Diffusion Movement of ions and molecules from places of higher concentration to places of lower concentration. - Electrochemical remediation Remediation technologies comprising electrochemical transport and transformation methods. - Electrokinetic screens Structures used to prevent radionuclides from diffusing from the polluted area into the environment. - Electromigration Transport of charged ions or ion complexes in solution. - Electroosmosis Movement of liquid relative to a charged stationary surface, - Electrophoresis Movement of charged particles relative to a stationary fluid. - Enhanced electrochemical remediation Use of pH control and additives to improve removal efficiency. - EURT East Urals Radioactive Trail area contaminated due to a nuclear accident. - Natural attenuation (NA) Remediation relying entirely on natural processes. - Permeable reactive barriers Passive in situ treatment zones of reactive material that degrades or immobilizes contaminants as groundwater flows through it. - Phytoremediation Soil remediation using living plants and their associated microorganisms. - Radionuclide or radioisotope An atom with an unstable nucleus whose excess energy is available to be imparted to a newly-created radiation particle within the nucleus or to an atomic electron. - Total material requirement (TMR) Sum of domestic and imported primary natural resources and their hidden flows.
Active thermography is sensitive to inhomogeneities at and below the surface of objects investigated. Thus, it should be useful for detecting plaster delaminations on concrete. In this paper, the results of field and laboratory investigations into plaster-covered concrete were compared. For evaluating the bonding state of the plaster it is not sufficient to study only the thermal contrasts at the surface of the investigated objects. The experimental results suggest that the overall thermal behaviour has to be considered.
As shown recently, the quantification of damage in historic masonry structures is possible by using active thermography. In this paper, a case study is presented concerning systematic studies of the determination of damage size and prognosis of damage increase inside a sandstone column by using different approaches of active thermography. Various heating sources as well as impulse and periodic heating have been compared. Reproducible investigations in regular time intervals for structural monitoring are possible.