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Heterogeneous catalysis is a key technology in modern industrial societies. The main steps of a catalytic process take place at the surfaces of complex materials. For the investigations of these surfaces X-ray photoelectron spectroscopy is widely used and fits ideally. At some suitable examples, it will be explained how XPS can help to understand such catalysts better. The focus is on selective oxidation catalysts, one of the main challenges of present research. Here it will illustrate, how changes in the near surface region influence the catalyst performance and, herewith the different stages (activation, maximum performance and deactivation) in the life of catalysts. Additionally, it will be stressed out how important information at different depth regions (surface, near-surface region, bulk) can be useful for comprehensive understanding of the material.
Another important subject is nanostructured catalysts with molecular sieves as supports or defined complexes as precursors. Finally, the combination of XPS with other methods used in the analysis of catalysts, e.g. electron microscopy, X-ray absorption spectroscopy and low energy ion scattering will be discussed.
Unternehmen der chemischen Industrie müssen neuen Pfade beschreiten, um in einem veränderten Umfeld erfolgreich bestehen zu können. Dazu gehört insbesondere, das Potenzial digitaler Technologien zu nutzen. Die volle Integration und intelligente Vernetzung von Systemen und Prozessen kommt allerdings nur zögerlich voran. Dieser Beitrag ist ein Loblied auf die Feldebene. Er möchte dazu ermutigen, die Digitalisierung der Prozessindustrie auf Basis smarter Sensorik, Aktorik und Kommunikation ganzheitlicher zu denken und informiert über aktuelle technische Perspektiven, wie das Ein-Netzwerk-Paradigma, Ad-hoc-Vernetzungen, Edge-Computing, FPGAs, virtuelle Maschinen oder Blockchain. Diese geben smarter Sensorik, Aktorik und Kommunikation eine völlig neue Perspektive.
Ultrasonic monitoring, making use of the sensitivity of the coda of repeated transmission meas-urements to changes in stress, temperature, moisture, as well as localized or distributed damage, has gotten at-tention in structural health monitoring (SHM) research recently. Analysis methods such as coda wave inter-ferometry (CWI), including its nonlinear extension, have been shown to be able to measure ultrasonic wave velocity changes with a 1∙10-5 resolution, while indicators such as cross-correlation or cross-coherence have been used to distinguish between reversible and irreversible changes. Several small- and large-scale laboratory experiments have demonstrated that stress changes in structures can be captured or damage detected in a very early stage. The use of this technique for pre-warning before failure are currently under investigation, as well as detailed research on the physical causes and the connection between ultrasonic wave properties and materi-al/structural behavior. Recently, several of large-scale laboratory and real structures have been instrumented with embedded ultrasonic transducers to gather experience and evidence on how to use this technology in re-al-world applications. Preliminary results from installations on a new bridge, an existing bridge, a tunnel, a la-boratory earthquake test as well as a historic stadium in Germany, Poland, and the United States, respectively, are presented. Environmental influences (mainly temperature) and validation by load tests are discussed.
A combination of different complementary methods is employed to investigate scaling of the molecular dynamics of two different liquid crystals. Each method is sensitive to different kind of fluctuations and provides therefore a different window to look at the molecular dynamics. In detail, broadband dielectric spectroscopy is combined with specific heat spectroscopy and neutron scattering. As systems the nematic liquid crystal E7 and a discotic liquid crystalline pyrene are considered. First of all it was proven that both systems show all peculiarities which are characteristic for glassy dynamics and the glassy state. Especially for the nematic liquid crystal E7 it could be unambiguously shown by a combination of dielectric and specific heat spectroscopy that the tumbling mode is the underlying motional process responsible for glassy dynamics. Dielectric investigations on the discotic liquid crystalline pyrene reveal that at the phase transition from the plastic crystalline to the hexagonal columnar liquid crystalline phase the molecular dynamics changes from a more strong to fragile temperature dependence of the relaxation rates. Moreover a combination of results obtained by specific heat spectroscopy with structural methods allows an estimation of the length scale relevant for the glass transition.
Interest in the type of skin used in scriptural materials and preparation methods increased from the nineteenth into the twentieth century. This was due partly to the number of newly discovered fragments and to the invention of new instruments and scientific procedures to identify animal skins and produce qualitative means to demonstrate specific preparation reagents and techniques. The invention of various means of analyzing the DNA of organic materials brought about a revolution in archaeology and in conservation. Difficulties in overcoming contamination of archaeological samples resulted in a number of controversies but also produced advances and improvement in the techniques of ancient DNA analysis and interpretation of results.
Raw data from metabolomics experiments are initially subjected to peak identification and signal deconvolution to generate raw data matrices m × n, where m are samples and n are metabolites. We describe here simple statistical procedures on such multivariate data matrices, all provided as functions in the programming environment R, useful to normalize data, detect biomarkers, and perform sample classification.
In this paper, we discuss the importance of scientifically investigating cultural artefacts in a non-invasive way. Taking as test case Leonardo da Vinci’s Manuscript with anatomic drawings and notes, which is stored in Weimar, we clarify fundamental steps in the chronology of this folio. By means of microscopy, infrared reflectography, UV photography, and X-ray fluorescence analysis, we were able to identify various types of sketching material and several varieties of iron gall ink. For his sketches, Leonardo used two different sketching tools, a lead pencil and a graphite pencil, as well as several types of ink for developing these sketches into drawings. With regard to ink, it is important to observe that there is no difference between the ink Leonardo used for drawing and the ink he used for writing text. Based on the materials analysed, we suggest a chronology for the creation of this unique folio.
Schwarz auf Weiß
(2019)
In der Sammlung des Naturwissenschaftlichen Kabinetts Johann Wolfgang von Goethes wird ein eher unscheinbares Stück Papier aufbewahrt, welches einen grauschwarzen Aufstrich aufweist. Bei genauerer Betrachtung glaubt man, drei Querstreifen mit rötlicher, weißlicher und bläulicher Farbe innerhalb des grauschwarzen Aufstrichs zu erkennen. Das Papier weist oben die Skizze eines Prismas, im mittleren Bereich am rechten Rand die Beschriftungen „violett/blau“, „weiß“ sowie „gelb/roth“ auf. Interessanterweise ist die Aufschrift „violett/blau“ dem eher rötlichen, die Aufschrift „gelb/roth“ dem eher bläulichen Querstreifen zugeordnet. Die rechte untere Ecke ist mit „Sk“ (Seebeck?) gekennzeichnet. Sowohl die Beschriftungen als auch die Skizze wurden mit einem Graphitstift ausgeführt. Das Papier ist auf eine Pappe mit Papprahmen geklebt und mit schwarzem Papier umwickelt. Es ist unumstritten, dass es sich bei diesem Objekt um das Ergebnis eines naturwissenschaftlichen Experiments handelt, doch was stellt es dar und lässt sich die ursprüngliche Versuchsanordnung aus dem vorliegenden Befund und weiterer, heute zugänglicher naturwissenschaftlichen Untersuchungen rekonstruieren?
Eine Vielzahl unterschiedlicher Materialien findet für die farbliche Gestaltung von Zeichnungen Verwendung. Einige Pigmente und Farbstoffe, d.h. Tinten, Stifte oder Kreiden, waren nur für den Gebrauch als Zeichenmittel vorgesehen – andere wiederum finden sich auch in der Tafel- oder Fassmalerei. Ausgehend von schwarzen Zeichenmaterialien soll zunächst eine allgemeine Typologie der Farbmittel entwickelt werden, um den Kosmos dieser Vielfältigkeit zu illustrieren. In einem zweiten Teil werden farbige Elemente am Beispiel von Rötel in Zeichnungen hinterfragt, deren Funktion und Bedeutung sich aus der Betrachtung heraus nicht unbedingt sofort erschließt. So diente die Farbe hier weder der naturgetreuen Nachahmung, noch wurde sie für eine nachträgliche Wertsteigerung eingesetzt. Der dritte Teil dieses Exkurses widmet sich schließlich solchen „farbigen“ Elementen, deren Konnotationen sich aus den Zeichnungen nicht ermitteln lassen und die daher zunächst irritieren. Diese vermeintliche Farbigkeit war aber ursprünglich vielleicht gar nicht intendiert, sondern ist vielmehr auf Alterungs- und Korrosionsprozesse zurückzuführen.
This chapter gives an overview about polymer optical fiber (POF) sensors with the focus on structural and civil engineering applications. POF properties such as the high-strain range, the low Young’s modulus, and specific scattering effects open new fields for fiber-optic sensing applications. POF properties, sensitivities, and cross-sensitivities that are relevant for sensing are introduced. Advantages and limitations are discussed. State-of-the-art POF sensors and application examples are presented in subsections with regard to their underlying measurement principles.
Per- and polyfluoroalkyl substances (PFAS) are a group of more than 4700 anionic and cationic anthrophonic substances which have been used extensively in a variety of products and industries due to their inert chemical stability and resistance to degradation by heat or acids. As a result of continuous use, mainly in aviation firefighting foams, thousands of industrial and military installations have been found to contain contaminated soil and groundwater resources. However, because of the continuous use of fluorinated consumer products, also effluents and sewage sludge from wastewater treatment plants (WWTPs) have been shown to be an important source of PFAS contamination into the aquatic environment. Resulting from recent stricter regulations and restrictions in the last years on the use of long chain (≥C8) PFAS, there is a significant shift in the chemical industry towards production of short (C4-C7) and ultrashort (C1-C3) chain alternatives. With the amendment of the Sewage Sludge Ordinance in 2017 the German legislation banned sewage sludge application on agricultural land, and by 2029/2032 sewage sludge will be completely prohibited from agricultural application. While environmental exposure of organic pollutants like PFAS, pesticides and pharmaceuticals are no longer desirable, phosphorus (P) from sewage sludge must still be used to produce high-quality P-fertilizers for a circular economy. Currently, plant-available P-fertilizers from sewage sludge/wastewater can be produced using a variety of treatment approaches including precipitation, leaching, and thermal treatment. However, the fate of legacy and emerging PFAS compounds during P leaching, precipitation and treatment from sewage sludge and wastewater is for the most parts still unknown.
Inductively coupled plasma-mass spectrometry (ICP-MS) is a well-established analytical method offering high sensitivity and multi-element analysis. ICP-MS has found acceptance in various application areas ranging from material analysis to applications in the life sciences. Within the last 15 years new strategies for the sensitive detection and accurate quantification of biomolecules in complex biomedical samples have been developed. Recent instrumental improvements have contributed to this progress.
As most of the biomolecules do not contain endogenous metals etectable with ICP-MS, bioconjugation with artificial metal-containing tags based on metal-loaded chelate complexes or nanoparticles is increasingly applied to determine biomolecules indirectly. Especially, the combination of immunohistochemical workflows using lanthanoid-tagged antibodies and ICP-MS detection provides new insights in the complexity and interdependency of cellular processes. Single-cell ICP-MS, also termed as mass cytometry, allows high-dimensional analysis of biomarkers in cell populations at single-cell resolution. For that purpose, lanthanoid isotope labelled antibodies are used to detect their corresponding target molecules. The visualisation of the elemental distribution is possible with laser ablation ICP-MS (LA-ICPMS) at high spatial resolution. Especially, the combination of LA with ICP time-of-flight mass spectrometry, also referred to as imaging mass cytometry (IMC), opens new possibilities for multiparametric tissue imaging at the single-cell level and even below. The lanthanoid localisation and concentration can be linked to their conjugated antibody target providing valuable information about surface markers, intracellular signalling molecules to measure biological function, and the network state of an individual cell in a tissue.
This book chapter focuses on new applications, where the multi-element capabilities of ICP-MS are used for the detection of lanthanoids applied as artificial elemental stains or tags for biomolecules and in particular antibodies.
Physico-chemical analyses of writing materials offer insight into various questions associated with historical, cultural, and conservational aspects of manuscript studies. The catalogue of questions that can be addressed with these methods includes authenticity, dating, the attribution of various parts of the text to different scribes and the relation between the primary and secondary texts. Similarly, preservation of the manuscripts requires knowledge of the composition of the original materials versus old repairs, identification of damage, as well as recognition of natural aging and degradation processes. The material sciences can contribute data about the chemical compositions of the writing materials, elucidation of the techniques of their production and the absolute age of organic components, as well as characterization of corrosion effects, evaluation of conservation treatment, and monitoring of the preservation state.
Although concrete itself is not a combustible material, concrete mixtures with high density, such has high-performance concretes (HPCs), are susceptible to significant damage during fires due to explosive spalling. Past research has shown that the inclusion of polymer fibres in high density concrete can significantly mitigate this fire damage. The exact mechanisms causing this increased spalling resistance are not yet fully under-stood, but it is thought that the fibres facilitate moisture transport during fire exposure, which in turn contributes to relief of internal stresses in the spalling-susceptible region. In this study, X-ray Computed Tomography (CT) was applied to observe the interaction between polymer fibres and cracking during thermal exposure. For this purpose, two concrete samples containing different polymer fibre types were subjected to incremental application of a defined thermal exposure. CT images were acquired before and after each thermal exposure and powerful image processing tools were used to segment the various material components. This enabled a detailed analysis of crack formation and propagation as well as the visualization and quantification of polymer fibre characteristics within the concrete. The results demonstrated that the orientation of both fibres and cracks in polymer-fibre reinforced concrete tend to be anisotropic. The results also indicated that crack geometry characteristics may be correlated with fibre orientation, with cracks tending to run parallel to fibre beds. Clear quantitative relationships were also observed between heating and increasing cracking levels, expressed in terms of both crack surface area and crack volume.
Nondestructive evaluation (NDE) is entering an era of the fourth industrial revolution and will undergo a major transformation. NDE is a vital part of industry and a successful move to NDE 4.0, it will require not just developing and embracing new technologies, but also developing and adopting new ways of working and becoming an integral part of the overall Industry 4.0. This will pose new challenges for the inspection personnel. To ensure the expected benefits from NDE 4.0, inspectors need stay in charge of the changing inspections. The promised autonomy and interconnectedness of NDE 4.0 will supersede the majority of traditional inspector tasks and will in turn require a different set of skills and raise different demands and challenges for the inspection personnel, thus conflicting the current “procedure-following”-“level I-III” paradigm. The new industry 4.0 technologies can be integrated into the current framework, but exploiting their full potential requires changes in the role of the inspectors. The inspectors will be relieved from the tedious and error-prone aspects of the current system. At the same time, they will need to take responsibility for increasingly complex automated systems and work in closer collaboration with other experts. We propose that the traditional inspector roles will be transformed into that of the system developer, caretaker, and problem solver, each requiring a specific set of skills and assuming different responsibilities. For full NDE 4.0, NDE must abandon its traditional role as a self-contained entity with well-defined boundaries and take its role in the wider system that is the industry 4.0.
NDE 4.0 in Civil Engineering
(2021)
Civil engineering industry is one of the most important industry sectors in the worldwide economy. It contributes significantly to the gross economic product and general employment. Even more important, it provides many of the basic needs of the society (e.g., housing, infrastructure, and protection from natural hazards). The concept of “Industry 4.0” or “Smart Production” has not yet made significant progress in the civil engineering industry. The designing, building, and operating processes are still widely dominated by the exchange of printed documents and drawings. Most objects (buildings and other constructions) are unique, and a large part of the production still requires a large amount of manual labor. As-built documentation and quality assurance are often neglected. Civil engineering is among the industry sectors with the lowest level of digitalization and the lowest gain in productivity. However, this is going to change. In the past decade, several drivers have challenged the ways clients, contractors, and authorities currently operate. These drivers include but are not limited to an increasing demand for serialization and automatization or the mandatory introduction of “Building Information Modeling” (BIM) in public procurement as well as the upcoming use of digital twins. NDE plays an increasing role in quality assurance, condition assessment, and monitoring of structures. However, with very few exceptions, applications are mostly nonstandardized and performed only at selected sites. To change this, the NDT-CE community including manufacturers, service providers, clients, and the scientific community must work consistently on open data formats, interfaces to BIM, standardization, and validated ways for a quantitative use of the results in the assessment of constructions.
The purpose of this contribution is to introduce and to apply the developed approach of incorporating non-destructively gathered measurement results (instead of deterministic information and assumptions) into a reassessment model of a typical prestressed concrete road bridge and to outline the advantages. An essential part is the quality evaluation of the non-destructively measured information, that deals primarily with two questions. Could the object or parameter to be obtained reliably detected and if, how accurate are the inspection results achieved? Therefore, the importance of the combination of a probability of detection (POD)-approach and measurement uncertainty calculations is emphasized. With regard to the introduced case-study it is shown, for which structure parameters an assumption deviating from the actual (and measurable) situation has a particularly strong (and possibly arithmetically unfavorable) influence on the structural reliability. Measurements on such parameters are particularly beneficial for a reliable and robust reassessment. In conclusion, the individual reassessment results without consideration and with consideration of evaluated non-destructive inspection results are compared.
Das Kupferstichkabinett der Hamburger Kunsthalle besitzt seit seiner Gründung vier Zeichnungen von Leonardo da Vinci (1452–1519). Sie sind Teil eines umfangreichen Legats des Hamburger Kunsthändlers Georg Ernst Harzen, das der Stadt Hamburg für die 1869 eröffnete Kunsthalle als Besitz übereignet wurde. Die Zeichnungen gelten aufgrund ihrer Provenienzen und stilistischen Verankerung im Werk Leonardos als gesichert. Weiterführende materialtechnologische Untersuchungen wurden nun erstmals anlässlich der Ausstellung »Leonardo da Vinci – Die Zeichnungen im Hamburger Kupferstichkabinett« durchgeführt.
In Goethes naturwissenschaftlichen Sammlungen, die als Arbeits- und Studiensammlungen, zum Teil aber auch als Lehrsammlung für den Sohn August angelegt sind, haben sich sowohl die eigentlichen Sammlungsobjekte als auch deren vermeintlich ursprünglichen Kontexte durch Beschriftungen, Etiketten und in Teilen noch existierende Präsentationsmedien erhalten. Es stellt sich jedoch die grundsätzliche Frage nach deren Ursprünglichkeit. Präsentieren sich die Objekte noch so wie zur Goethezeit oder erfuhren die historischen Dichotomien im Laufe der Zeit Veränderungen, sodass die zeitgenössischen Präsentationsformen und die damit verbundenen didaktischen Funktionen heute nicht mehr lesbar sind?
Das Ziel dieses Kapitels besteht darin, die Rolle von Konformitätsbewertung für die Erhöhung der Cybersicherheit von Produkten, Dienstleistungen und Prozessen zu betrachten. Dazu wird der Begriff Cybersicherheit beleuchtet sowie ausgewählte Cybersicherheitsnormen kurz vorgestellt. Im Folgenden wird der regulative europäische Rahmen für die Konformitätsbewertung aus ordnungspolitischer Sicht sowie der aktuelle Verordnungsentwurf zum Cybersecurity Act dargestellt und kritsch beleuchtet.
The paper presents rheometric results and hydration curves for cementitious systems based on cement mixed with different aqueous phases at solid volume fraction of = 0.45. The varied aqueous phases were deionized water, limewater, the filter residue of a cement paste mixed at w/c = 2.0, and the filtrate of cement paste at solid volume fraction of 0.45. Each cementitious system provided different amounts and sizes of particles formed in the aqueous phase. The pastes were observed with and without polycarboxylate ether based superplasticizer. It was observed that the presence of particles causes higher PCE saturation dosages to achieve a minimum value, but the minimum value is only affected in the case of large particles. In all cases with and without PCE, the presence of small particles causes increased plastic viscosity. In addition, with decreased number and size of hydrates in the aqueous phase the hydration was retarded, which was specifically pronounced in the presence of PCE
Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is nowadays a versatile and powerful analytical method for direct solid sample analysis. The applicability has been demonstrated for a wide variety of samples covering hard and soft materials. In an imaging mode the technique provides quantitative information on the elemental distribution within a sample. LA-ICP-MS imaging is of particular interest in biomedical research as the distribution of an element gives valuable insight on uptake and distribution of essential and toxic trace elements, administered contrast agents as well es nanoparticles. LA-ICP-MS is therefore a powerful complement to other imaging techniques. Recent instrumental improvements, especially in sample chamber design, have contributed to better sensitivity and spatial resolution enabling subcellular imaging. The book chapter provides a comprehensive overview about spatially resolved localisation and quantification of various nanoparticles in cells and tissue thin sections by LA-ICP-MS. Furthermore, different sample preparation strategies and internal standardisation and calibration approaches for bioimaging by LA-ICP-MS are summarized and discussed.
Metal-containing nanomaterials are used in numerous fields ranging from industrial applications to nanomedicine. Several studies have demonstrated that the physicochemical properties of nanoparticles have an impact on their pharmacokinetics, transfer and clearance. The high sensitivity and multielement capability of LA-ICP-MS enables the elucidation of interactions between tissue components and nanomaterials used as imaging probes or drug carriers. Potential toxic effects are investigated as well. Thus, LA imaging significantly supports the clinical translation of safe and efficient nanoparticles for diagnostic and therapeutic purposes.
Industrial Radiology is used for volumetric inspection of industrial objects. By penetration of these objects (typically weldments, pipes or castings) with X-ray or Gamma radiation the 3D-volume is projected onto a 2D image detector. The X-ray film is the oldest radiographic image detector and still in wide use in industry. The industrial X-ray film systems used today differ from these used in medicine. Medical film systems are described well in the literature, but industrial film systems not. So we start with a description of the properties and standards for industrial film systems. The requirements on image quality are defined by several standards and can be verified with different image quality indicators (IQIs). They describe the ability of the human being to detect small and low contrast indications in a noisy image background. The essential parameters for digital industrial radiology are described.
Since about 30 years electronic image detectors are gradually replacing the industrial film. These detectors are based on storage phosphor imaging plates in combination with Laser scanners (“Computed Radiography”, CR) or a variety of different digital detector arrays (DDA). Typical applications of CR and DDAs are discussed as well as new possibilities by digital image processing, which is enabled by the computer based image handling, processing and analysis.
"The reassessment of bridges continues to take great importance both nationally and internationally. A major challenge is to find computation models reflecting the actual properties of the considered structures sufficiently accurate. Besides regular inspections, the conduction of advanced measurements is suitable to generate reliable information about a structure to be assessed. Prior to incorporating measurement results in reassessment, the relevance, the trueness, and the precision of the measured information needs to be stated. On the one hand, the use of information whose quality has not been assessed can lead to errors with serious consequences. On the other, the measurement of irrelevant information is inefficient. Although the use of measured data in assessment is currently mostly unregulated, their appreciation in reliability analyses is beneficial since the built environment can be assessed more realistically. Utilizing NDT in reassessment has the potential to extend remaining lifetimes of a structure, save resources, and improve infrastructural availabilities. The power of judgment regarding the decision on the reliability of an existing structure can be increased.
In this contribution, an approach is outlined to process non-destructively gathered measurement data in a comparableway in order to include themeasured information in probabilistic reliability assessments of existing structures. An essential part is the calculation of measurement uncertainties. The effect of incorporating evaluated NDT-results is demonstrated by means of a prestressed concrete bridge and GPR measurements conducted on this bridge as a case-study. The bridge is assessed regarding SLS Decompression using the NDT-results."
The book chapter first analyses the history of higher education in Europe. Second step describes the current Bologna process. Finally, the rule of the Bundesanstalt für Materialforschung und -Prüfung (BAM) in supporting PhD-students during their research and preparation of theire theses in cooperation with Universities is described
Der Beitrag beschäftigt sich mit zerstörungsfreien Untersuchungen an den Farbmitteln früher Bauhauszeichnungen. Mit welchen Farbmitteln wurden diese Zeichnungen gestaltet? Wurden hier neueste Zubereitungen genutzt, von denen viele im ersten Drittel des 20. Jahrhunderts gerade auf den Markt kamen, oder fanden – der ebenfalls am Bauhaus propagierten Materialökonomie folgend – althergebrachte Materialien Verwendung, die günstiger zu beschaffen waren? Weitere Fragen widmen sich dem Themenkomplex Original, Kopie und Nachahmung sowie der Auffindung von Fälschungen. Restauratorische, konservatorische und kuratorische Fragestellungen und Entscheidungen sind grundsätzlich damit verknüpft. Zwölf exemplarisch vorgestellte Zeichnungen ermöglichen einen guten Über blick über die verwendeten Farbmittel des frühen Bauhauses von 1919 bis 1925. Trotz der Vielfalt der betrachteten Studien, Entwürfen und Arbeitsblättern, ergibt sich ein homogenes Gesamtbild. Bis auf wenige Ausnahmen dominieren anorganische Pigmente die Farbmittelpalette. Dieser Befund wird durch eine weitaus größere Stichprobe materialtechnologisch untersuchter Zeichnungen aus dem Bestand des Bauhaus-Museums Weimar bestätigt
This paper addresses the sensitive issue of authenticating unprovenanced manuscripts of high monetary value to certify they are genuine. Over the last decade, the popularity of material studies of manuscripts using non-destructive testing (NDT) has increased enormously. These studies are held in especially high esteem in the case of suspicious writings due to the methodological rigour they are reputed to contribute to debate. We would like to stress that materials analysis alone cannot prove that an object is genuine. Unfortunately, audiences with a humanities background often tend to disregard the technical details and treat any published interpretation of instrumental analysis as an objective finding. Four examples are outlined here to illustrate what questionable contributions the natural sciences can make in describing manuscripts that have actually been forged.
Der fabelhafte Möglichmacher
(2022)
High-temperature corrosion is a widespread problem in various industries.
As soon as a hot and reactive gas (CO2, O2, H2O, SO2, NOx, etc.) is in contact with a solid, physico-chemical processes at the surface and interfaces lead to material degradation. The processes are dynamic and controlled by thermodynamic and kinetic boundary conditions. Whether a reaction product is protective or not depends on various factors, such as chemical composition of the solid and the reactive media, surface treatment as well as diffusion and transport paths of cations and anions. Resulting chemical and structural inhomogeneities with the corrosion layers are characterized by off stoichiometry within cationic and anionic sub lattices. The competitive processes can be studied by various techniques of applied crystallography.
This chapter gives an overview on the challenges of chemical-structural Analysis of reaction products by crystallographic methods such as X-ray diffraction and X-ray near-edge structure spectroscopy and scanning electron microscopy electron backscatter diffraction (SEM-EBSD) for corrosion science.
The through-life management of our constantly ageing infrastructure is a basic requirement in order to ensure their structural safety and serviceability. Each structure experiences deterioration processes with time leading to a decrease of structural safety and serviceability. The design of new structures considers the expected deterioration for a defined period, the design service life. However, a frequent survey of structural safety controlling structural condition should be mandatory and a maintenance plan should be an integral part of the design. In addition, many structures have exceeded their design service life already or are very close to it leading to an increasing demand for condition assessment. On the one hand, assumptions made during design are not valid any more due to change of the loads, e.g., increasing traffic loads in terms of number and weights. On the other hand, design codes evolved over time in such a way that existing structures do not comply with today’s standards. In all these cases, the through-life management is an important tool to maintain the accessibility of existing structures with known reliability.
In line with the new Model Code for Concrete Structures, which includes guidance for both – design of new structures and assessment of existing structures, the Task Group 3.3 focused on the compilation of a state-of-the-art guideline for the through-life management of existing concrete structures, including:
Data acquisition by testing and monitoring techniques;
Condition assessment for the evaluation of existing structures;
Performance prediction using advanced methods;
Decision-making procedures to perform a complete assessment of existing structure.
The overall objective of the through-life management is the assessment of the current condition and the estimation of the remaining service life under consideration of all boundary conditions.
Calibration-free methods in laser-induced breakdown spectroscopy, CF LIBS, serve as an alternative to calibration-based LIBS techniques. Their major advantage is the ability for fast chemical analysis in situations where matrix-matched standards are not readily available (as, e.g., in the analysis of biological materials and remote analysis) or amount of samples are limited. Their main applications are in the industry, geology, biology, archeology, and even space exploration. This chapter overviews the principle of operation and performance of CF LIBS techniques.
The structure and composition of ancient gold objects retain information about their long history of manufacture, from the exploitation of the ore to the finishing touches, as well as evidence of their use, deposition, and degradation. By developing an efficient analytical strategy, it is possible to retrieve that information. This chapter sets the necessary foundation 131to explore fully the analytical results presented in the following chapters of this volume. The techniques employed in the analyses of the Egyptian jewellery are described and the analytical parameters provided. For more established techniques, only brief introductions are presented, while more recent developments are presented in greater detail.
Our standard protocol for the characterisation of writing materials within advanced manuscript studies has been successfully used to investigate manuscripts written with a pure ink on a homogeneous writing surface. However, this protocol is inadequate for analysing documents penned in mixed inks. We present here the advantages and limitations of the improved version of the protocol, which now includes imaging further into the infrared region (1100−1700 nm).