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This study focuses on the analysis of a corpus of manuscripts found in Fustat (medieval Cairo, Egypt) in the biggest medieval “archive” found until now: the Cairo Geniza. The giant collection of mostly Jewish documents has been attracting scholars’ attention a lot but so far, the material aspects of these documents seem to have been mainly neglected.
Application of scientific methods of analysis, especially X-Ray fluorescence characterization, contributes to our understanding of the materials used for production of manuscripts during the Middle ages.
Our corpus of the 11th century manuscripts comprises manuscripts written by scribes belonging to three Jewish communities that co-existed in Cairo during this period: the Karaites, the so-called Jerusalemites (or Palestinian) and the so-called Babylonians (or Iraqi), three different communities with different traditions and different leaders. The differences manifest themselves also in the paleographical properties of the manuscripts produced within each community. Can we extend the differences detected by the paleographical analysis to differences in composition of the writing materials and especially the composition of the inks? Or can we relate the differences in the composition to the manuscript type (legal, private...), or to another criterion. In this presentation, we offer answers to some of the questions using statistical analysis of the measurements results.
Measuring means knowing. The structural engineer’s Knowledge about structures is vitally important for the assessment of their structural safety. This contribution shows, how non-destructive testing methods can be used to collect valuable Information about existing structures. This value is expressed in this paper by the usability in probabilistic assessments and thus by the reliability of the information. The development of non-destructive testing methods in civil-engineering allows the realistic measurement and visualization of inner constructions of concrete components with a minimum of destructive interventions.
The evaluation of the quality of measurement data is of fundamental importance for quantitative measurements in order to ensure the objectivity of testing and evaluation and to assess the reliability of the knowledge acquired. Both systematic and random deviations must be identified, quantified and taken into account to obtain statistically sound data. The Focus of this contribution is on the methodical path, how displayed measurement data can be processed into reliable knowledge.
It is not about developing assessment methods but about providing
necessary knowledge to increase their operational usability.
X-ray photoelectron spectroscopy (XPS) provides elemental and chemical information from the outermost ~10 nm of the sample surface. This is in the same order of magnitude as the thickness of the outer bacterial membrane of gram-negative bacteria, as well as outer membrane molecules as exopolysaccharides and lipopolysaccharides, commonly attached to the cell surface. With the development of near-ambient pressure (NAP)-XPS, bacteria can be analysed with minimal sample preparation.
EnviroESCA is a laboratory based NAP-XPS instrument, equipped with a monochromated Al Kα radiation source and a differentially pumped energy analyser connected to an exchangeable sample environment. It allows for measurements in various gas-atmospheres, including water vapor, which makes it possible to characterise bacteria and other biological samples close to their natural, hydrated state. Artificial model-biofilms of exopolysaccharides, planktonic Pseudomonas Fluorescens and biofilms of Escherichia Coli have been characterised in hydrated and dried state.
High-resolution XPS-spectra from carbon, oxygen, nitrogen and phosphorous can be assigned to carbohydrates, lipids and proteins in general agreement with literature. Especially the carbon 1s peak is of interest. A series of measurements of an E. coli biofilm from 11 mbar in humid environment to 1 mbar air reveal changes in the C1s peak, which suggests that the bacterial surface undergo substantial Change.
The CLEAN ENERGY Flagship is an initiative designed to utilize recent game changing developments in digital, materials and manufacturing technologies to catalyze a radical paradigm shift towards clean, reliable, efficient and cost-optimal energy.
Unifying and drastically accelerating radically new energy material design, processing and integration across the entire value chain addressing energy production, conversion, storage and systems.
CLEAN ENERGY participants are all distinguished research organisations that each benefit from their own industry networks and contacts with regions and state-level activities and have a long history of collaborating with each other (for 10 years now under the umbrella of EERA) within a European collaborative framework.
Through EERA, CLEAN ENERGY aims to become a crucial partner in the SET-Plan, supporting long-lasting approaches through its established networks and internal collaborations.
The equation of state for plasmas containing negative and positive ions of elements and molecules formed by these elements is modeled under the assumption that all ionization processes and chemical reactions are at local thermal equilibrium and the Coulomb interaction in the plasma is described by the Debye–Hückel theory. The hierarchy problem for constants of molecular reactions is resolved by using three different algorithms for high, medium, and low temperatures: the contraction principle, the Newton–Raphson method, and a scaled Newton–Raphson method, respectively. These algorithms are shown to have overlapping temperature ranges in which they are stable. The latter allows one to use the developed method for calculating the equation of state in combination with numerical solvers of Navier–Stokes equations to simulate laser-induced Plasmas initiated in an atmosphere and to study formation of molecules and their ions in such plasmas. The method is applicable to a general chemical network. It is illustrated with examples of Ca–Cl and C–Si–N laser-induced plasmas.
Laser induced plasma (LIP) is a highly dynamic, short living event which presents significant difficulty for both diagnostics and modeling. The former requires precise spatially- and time-resolved measurements on a micron-nanosecond scale while the latter needs numerous descriptive parameters; many of them can only be obtained from experiment. Diagnostics and modeling should always complement each other for obtaining a truthful picture of LIP.
In this presentation, a newly developed collisional-dominated model will be presented. The model is based on the coupled Navier-Stokes, state, radiative transfer, material transport, and chemical equations. The model incorporates plasma chemistry through the equilibrium approach that relies on atomic and molecular partition functions. Several chemical systems are modeled including Si-C-Cl-N and B-H-Cl systems.
The model is used to study the equilibrium states of the systems as functions of the concentrations of plasma species and plasma temperature. The model also predicts the evolution of number densities of atomic and molecular species in the expanding plasma plume.
This course will provide an introduction to plasma diagnostic techniques. The major focus of the course will be on the discussions of the practical procedures as well as the underlying physical principles for the measurements of plasma fundamental characteristics (e.g., temperatures, thermodynamic properties, and electron number density). Particular emphasis will be placed on inductively coupled plasma–atomic emission spectrometry, but other analytical plasmas will also be used as examples when appropriate. Selected examples on how one can manipulate the operating conditions of the plasma source, based on the results of plasma diagnostic measurements, to improve its performance used for spectrochemical analysis will also be covered. Topics to be covered include thermal equilibrium, line profiles, temperatures, electron densities, excitation processes, microreactions, pump and probe diagnostics, tomography, temporal and spatial resolution. Basics of plasma computer modeling will be presented.
This poster deals with improvements and characteriztion of small-angle scattering limitations, by looking at the trifecta of Data collection and uncertainty propagation, data analysis methodologies, and real-world tests. It is found that - with appropriate care and instrumentation - accuracies of 1% on mean nanomaterial sizes, and 10% on the size distribution width as well as the volume fraction can be achieved.
Pulsed thermography is a well-known non-destructive testing technique and has proven to be a valuable tool for examination of material defects. Material defects are often simulated by flat-bottom holes (FBH) or grooves. Typically, analytical 1D models are used to determine the defect depth of FBHs, grooves or delaminations. However, these models cannot take into account lateral heat flows, or only to a limited extent (semi-empirical model). They are therefore limited by the FBHs aspect ratio (diameter to remaining wall thickness), to ensure that the heat flow above the defect can still be described one-dimensionally. Here, we present an approach for quantitative determination of the geometry of FBH or grooves. For this purpose, the results of a numerical 2D model are fitted to experimental data, e.g., to determine simultaneously the defect depth of a FBHs or groove and its diameter or width, respectively. The model takes lateral heat flows into account as well as thermal losses. Figure 1 shows the temperature increase of a pulsed thermography measurement at three different locations on the sample. The numerical model is fitted to the experimental data (red lines) to quantify the groove. The numerical simulation matches the experimental data well.
The formation and alignment of gel fibres in alkanes (solvents) was investigated. The gel fibres consist of small amphiphilic molecules containing a C60 molecule and a small ligand chain. Under the right conditions, these self-assemble in core-shell micelles, which themselves pack into micron-sized fibre-like structures. These can be aligned using a strong magnetic field, as investigated using SANS with a 17T superconducting magnet at a range of field strengths.
More than 80 representatives of SMEs, industrial companies and research institutes met on September 12 at the workshop "Challenges in Additive Manufacturing: Innovative Materials and Quality Control" at BAM in Adlershof to discuss the latest developments in materials and quality control in additive manufacturing.
In special lectures, researchers, users and equipment manufacturers reported on the latest and future developments in additive manufacturing. Furthermore, funding opportunities for projects between SMEs and research institutions on a national and European level were presented.
The technique of painting on the reverse side of a glass panel was rediscovered by German artists at the beginning of the 20th century. In contrast to other paint techniques (e.g. panel and mural painting), the paint layers are applied in reverse succession starting with the foremost paint layer and ending with the primer (backmost layer). The paintings are viewed in reflected light, thus revealing an impressive gloss, luminosity and depth of colour. The artist group “Der Blaue Reiter” (the Blue Rider) around W. Kandinsky and F. Marc got in touch with this technique in the summers of 1908 and 1909 and spread their knowledge in different regions. Our pioneering project is tracing this transfer of knowledge by a multidisciplinary approach in terms of art history, painting technology and material science. More than 100 artists and >1000 reverse paintings on glass (1905-1955) were identified during the project. This numbers clearly point out that this technique was by far more important for modern art than previously assumed. In-situ, non-invasive measurements (XRF, Raman, VIS, DRIFTS) on a well-considered selection of 67 paintings reveal the broad palette of colorants ranging from traditional to experimental materials. Special attention is paid on artists who are strongly connected to Berlin. Demonstrative examples by W. Dexel, G. Muche and L. Hildebrandt are used to discuss analytical challenges and highlights.
ALCOREF is a project within the European Metrology Programme for Innovation and Research (EMPIR. It is part of the 2016 EMPIR Research Potential Call dedicated to build up metrological and research capacity in less developed National Metrology Institutes (NMIs).
The project will develop long term expertise for the production and certification of ethanol/water reference materials in the participating NMIs. Materials to be developed will be suitable for the calibration and approval of evidential breath alcohol analysers as defined by recommendation R 126 of the International Organization of Legal Metrology (OIML). Certification includes the characterisation of the materials, assessment of homogeneity, stability and uncertainty. Target certified values and volumes will address end-users’ needs regarding regional legal limits for alcohol in traffic and the instrumentation for breath analyser calibration available in different countries. Thus, the project supports the law enforcement of national drink-driving legislation.
The consortium comprises of 11 institutions from 10 European countries. Project participants will establish reliable analytical methods for the purity assessment of ethanol, such as Karl-Fischer titration, to achieve traceability of their certified values. Chromatographic or density methods for the quantification of ethanol in water will also be established, validated and applied for homogeneity and stability assessment. An interlaboratory comparison will be conducted within the European Association of National Metrology Institutes’ (EURAMET) Technical Committee Metrology in Chemistry to test the equivalence of the new certified reference materials and the analytical methods implemented.
The poster will present the outline and first results of the ALCOREF project.
This study focuses on the analysis of a corpus of manuscripts found in Fustat (medieval Cairo, Egypt) in the biggest medieval “archive” found until now: the Cairo Geniza. The giant collection of mostly Jewish documents has been attracting scholars’ attention a lot but so far, the material aspects of these documents seem to have been mainly neglected.
Application of scientific methods of analysis, especially X-Ray fluorescence characterization, contributes to our understanding of the materials used for production of manuscripts during the Middle ages.
Our corpus of the 11th century manuscripts comprises manuscripts written by scribes belonging to three Jewish communities that co-existed in Cairo during this period: the Karaites, the so-called Jerusalemites (or Palestinian) and the so-called Babylonians (or Iraqi), three different communities with different traditions and different leaders. The differences manifest themselves also in the paleographical properties of the manuscripts produced within each community. Can we extend the differences detected by the paleographical analysis to differences in composition of the writing materials and especially the composition of the inks? Or can we relate the differences in the composition to the manuscript type (legal, private...), or to another criterion. In this presentation, we offer answers to some of the questions using statistical analysis of the measurements results.
The Cairo Geniza is an “archive” discovered in the 19th century in Ben Ezra Synagogue in Fustat, a district in Old Cairo (Egypt), located south of the center of modern Cairo. The giant collection of mostly Jewish documents that vary in genres, languages and writing supports contains a large number of early medieval Hebrew manuscripts, mostly in fragmentary form. The larger part of the Cairo Geniza is stored today in the Cambridge University Library (CUL).
The Geniza provides sources for the literary, linguistic, historical studies of the various aspects Jewish life. As the documents attest, at least two Jewish communities co-existed in Fustat up to 11th century: a so-called Babylonian and Palestinian. These communities had different leaders, different traditions and lived independently. The differences seem to manifest themselves also in the paleographical, codicological and some material properties of the manuscripts produced by each community.
The aim of this project is to compare the inks used in the Jewish documents depending on different variables: support (paper, parchment), purpose of the manuscript (legal, private, religious), provenance of the scribe. For the determination of the inks type and composition we had to choose non-invasive, non-destructive and portable techniques to analyse the corpus directly in the CUL.
The analyses were carried out with a mobile energy dispersive micro-X-ray spectrometer ArtTAX® (Bruker GmbH, Berlin, Germany), which consists of an air-cooled, low-power molybdenum tube, polycapillary X-ray optics (measuring spot size 70 µm in diameter), an electrothermally cooled Xflash detector, and a CCD camera for sample positioning (Bronk et al 2001, Hahn et al. 2010). All measurements are executed using a 30 W low-power Mo tube, 50 kV, 600 µA Mo tube, and with an acquisition time of 15 s (live time) to minimize the risk of damage (Fig. 1, 2).
Fig. 1: XRF spectrometer probe above a manuscript fragment
Fig. 2: Typical element profile of a XRF linescan
The Dino Lite digital stereomicroscope (Fig. 3) features built-in LED illumination at 395 nm and 940 nm and a customized external white light source. During use, the microscope is fastened to a small tripod or mounted on a Plexiglas ring holder that incorporates a white light source.
Fig. 3: Dino Lite digital stereomicroscope
Fig. 4: Details of one fragment (T-S 16.124) observed with the Dino microscope (x20). On the left, when illuminated with NIR (Near-Infrared, 940 nm) light, the ink fades, indicating iron-gall ink. On the right, the image under NIR light does not change. It is carbon ink.
On example of these studies is the manuscript T-S 16.124 (Cambridge University Library, Fig. 5) whom belongs to the third corpus. It is a deed, written in Hebrew, dated from 1328 (= 1017 CE) and witnessed by a very high number of people (6) comparing to the standard of similar documents (between 2 and 3), from at least two different Jewish communities in Fustat (trans congregational). The verso is written in Arabic (Bareket 1999).
Fig. 5: Manuscript T-S 16.124 (Cambridge University Library)
To compare the inks, we used the fingerprint model. This method relies on the determination of characteristic elemental compositions and represents the amount of a minor constituent relative to the main component, iron in iron gall ink (Malzer et al. 2004, Hahn et al. 2004, Rabin et al 2014). However, a calculation of a fingerprint based on XRF measurements is not possible in the case of carbon ink since carbon, its main component, cannot be detected with this technique.
Fig. 6: Ink fingerprint T-S 16-124 (recto) normalized to iron (Fe)
Conclusion
We show that using reflectography and XRF analysis it is possible to sort the inks according to their type. In the case of the iron-gall inks, use of the ink fingerprint, i.e. amount of the vitriol components normalized to iron we can make direct comparisons of the ink composition.
We would like also to stress that though the methods of material analysis listed above have been successfully employed in the field of cultural heritage and conservation including ancient and medieval manuscripts they have not yet been used to study fragments from the Cairo Genizah. Therefore, we believe that this research project is a pioneering study that will provide new insights into the history of Hebrew writing materials, their production techniques and materials and, thus, contribute new data to the field of Hebrew paleography.
The Cairo Genizah is a well-known “archive” discovered in the 19th century in Ben Ezra Synagogue in Fustat, a district in Old Cairo (Egypt), located south of the center of modern Cairo. The giant collection of mostly Jewish documents that vary in genres, languages and writing supports contains a large number of early medieval Hebrew manuscripts, mostly in fragmentary form. The larger part of the Cairo Genizah is stored today in the Cambridge University Library, containing about 200,000 fragments.
The Genizah provides sources for the literary, linguistic, historical studies of the various aspects Jewish and non-Jewish life. As the documents attest, at least two Jewish communities co-existed in Fustat up to 11th century: a so-called Babylonian and Palestinian. These communities had different leaders, different traditions and lived independently. The differences manifest themselves also in the paleographical properties of the manuscripts produced by each community.
Although Genizah 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 used, in order to obtain insights on trade, local production techniques and social structures.
Can we extend the differences detected by the paleographical analysis to differences in composition of the writing materials ? Can we relate the differences in the composition to a community, to the manuscript type (legal, private...), or to another criterion?
While studying the socio-geographic history of inks, division 4.5 of the BAM (Bundesanstalt für Materialforschung und Prüfung) together with the Centre for the Study of Manuscript Cultures in Hamburg has developed a protocol for ink analysis. It consists of a primary screening to determine the type of the ink, and a subsequent in-depth analysis using several spectroscopic techniques. The XRF elemental analysis aims primarily at understanding the fingerprints of inks containing metals, making it possible to distinguish among different inks.
Our own research aims primarily at recreating a socio-geographic history of inks, parchment, and papyrus and includes the comparative analysis of the writing materials of the Dead Sea Scrolls, ink and papyrus in Ancient and Hellenistic Egypt, and inks in documents from various contemporary medieval communities in Fustat (first nucleus of Cairo). During many years of study, we concluded that the continuous production of Coptic manuscripts from late Antiquity to the Middle Ages offers a unique opportunity for historical study of the ink in a large geographic area. Thanks to the collaboration with the ERC project “PAThs” (www.paths.uniroma1.it), based at the University of Rome La Sapienza, and within the activities of a PhD research dedicated to this topic, we therefore created a new branch of our project focused entirely on the analysis of Coptic inks, pigments, and dyes. This pioneering systematic study of writing materials coming from a specific area and time frame (5th-10th century) aims not only at a better understanding of the complex Coptic multicultural and plurilingual society, but also and mainly at clarifying the links among the Coptic and other societies between the ancient and medieval eras. Finally, it will cast light on the history of the technological development of inks in the eastern world, from Antiquity to the middle ages.
While studying the socio-geographic history of inks, division 4.5 of the BAM (Bundesanstalt für Materialforschung und Prüfung) together with the Centre for the Study of Manuscript Cultures in Hamburg has developed a protocol for ink analysis. It consists of a primary screening to determine the type of the ink and a subsequent in-depth analysis using several spectroscopic techniques: XRF, FTIR, and Raman. In most cases, we can obtain satisfactory results using a non-invasive protocol. However, mixed inks that contain no metals evade such a protocol. These inks constitute a heterogeneous group of media used especially in the Middle East and the Islamicate world since at least the 10th century; they are characterized by blending carbon ink and tannins, with or without the addition of vitriol.
Our own research aims primarily at recreating a socio-geographic history of inks, parchment, and papyrus and includes the comparative analysis of the writing materials of the Dead Sea Scrolls, ink and papyrus in Ancient and Hellenistic Egypt, and inks in documents from various contemporary medieval communities in Fustat (first nucleus of Cairo). During many years of study, we concluded that the continuous production of Coptic manuscripts from late Antiquity to the Middle Ages offers a unique opportunity for historical study of the ink in a large geographic area. Thanks to the collaboration with the ERC project “PAThs” (www.paths.uniroma1.it), based at the University of Rome La Sapienza, and within the activities of a PhD research dedicated to this topic, we therefore created a new branch of our project focused entirely on the analysis of Coptic inks, pigments, and dyes. This pioneering systematic study of writing materials coming from a specific area and time frame (5th-10th century) aims not only at a better understanding of the complex Coptic multicultural and plurilingual society, but also and mainly at clarifying the links among the Coptic and other societies between the ancient and medieval eras. Finally, it will cast light on the history of the technological development of inks in the eastern world, from Antiquity to the middle ages.
KorroPad - New Test Method for the Investigation of the Passive Layer Stability of Stainless Steels
(2018)
The KorroPad is a gel-based indicator test designed for the electrochemical determination of the passive layer stability and localization of surfaces of stainless steels threatened by localized corrosion. Different investigations and studies on the performance of the KorroPad as well as field trials by industrial users the have proven the principal suitability of the KorroPad method to assess the passive layer stability of stainless steels. The electrochemical mode of action will be described in detail and also the limitations of the applicability will be demonstrated. The influence of different surface finishes has been investigated and verified by known methods for describing corrosion resistances. As a result, the increased corrosion susceptibility of two ground surfaces has been detected, but also the corrosion resistance of further surface finishes could be confirmed. Furthermore the KorroPad test was used for the investigation of the influence of time and humidity on the passive layer development on different stainless steels.