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In this article paper, leather from book cover and metal lock from an 18th century church book were studied. The book was printed during the time of Mihai Constantin Șuțu, with the blessing of the Metropolitan of Moldova, Iacov Stamati. The analytical method used to study the components and the methods of obtaining all the important parts was the non-destructive technique SEM-EDX. The results regarding the used paper showed typical intermeshed cellulose fibers. In the case of leather, due to its advanced state of degradation, it was impossible to determine the type of animal from which the skin was used. The elemental analyses (EDX) of the metal lock indicated that it was made of brass. The results of the study of 18th century parts of the book, gave important information about the way of paper manufacture, the conservation state of the cover and the way that the metal lock was made and the safe way to clean it in the restoration and conservation process. [ABSTRACT FROM AUTHOR]

A paper-based membrane coated by graphitic carbon nitride (g-C3N4) is prepared via a dip-coating method and used as a separator for sodium metal batteries with merits of low cost and environment-friendliness. Introduction of g-C3N4 effectively improves the ionic conductivity and the structural stability of the separator. Compared with traditional polyethylene separators and Al2O3-coated separators, the g-C3N4-coated separators show better electrolyte wettability, thermal stability, and electrochemical stability. Therefore, Na||Na3V2(PO4)3 battery using the g-C3N4-coated separator exhibits better cycling stability and higher rate capability. These results prove that the g-C3N4-coated paper-based separator is expected to become the next generation of low-cost and high-safety separator in sodium metal batteries. [ABSTRACT FROM AUTHOR]

Abstract: A chordal graph is the intersection graph of a family of subtrees of a host tree. In this paper we generalize this. A graph has an -representation if there exists a host tree T of maximum degree at most h, and a family of subtrees of T, all of maximum degree at most s, such that if and only if . For given , and t, there exist infinitely many forbidden induced subgraphs for the class of -graphs. On the other hand, for fixed , every graph is an -graph provided that we take t large enough. Under certain conditions representations of larger graphs can be obtained from those of smaller ones by amalgamation procedures. Other representability and non-representability results are presented as well. [Copyright &y& Elsevier]

The main topic of this paper is the investigation of generalized amalgamation properties for simple theories. That is, we are trying to answer the question of when a simple theory has the property of n-dimensional amalgamation, where two-dimensional amalgamation is the Independence Theorem for simple theories. We develop the notions of strong n-simplicity and n-simplicity for 1≤n≤ω, where both “1-simple” and “strongly 1-simple” are the same as “simple”. For strong n-simplicity, we present examples of simple unstable theories in each subclass and prove a characteristic property of strong n-simplicity in terms of strong n-dividing, a strengthening of the dependence relation called dividing in simple theories. We prove a strong three-dimensional amalgamation property for strongly 2-simple theories, and, under an additional assumption, a strong (n+1)-dimensional amalgamation property for strongly n-simple theories. In the last section of the paper we comment on why strong n-simplicity is called strong. [Copyright &y& Elsevier]

The presence of toxic metals on paper pulp and the migration of these metals to food from the food package is receiving significant attention. The final exposure levels for consumers depend on two main processes. First the potential of metals to bind paper pulp during manufacture. Second, the metal potential to migrate from paper to food during storage and use.Binding and unbinding processes are modelled for cadmium kinetics through kinetic approaches.The cadmium concentration in paper pulp is estimated from the cadmium concentration in the water–pulp liquor during manufacture, the temperature, and contact time. Two food simulants have been employed for desorption studies, water and acetic solution (3%, w/w). As expected, under acidic conditions desorption is total and rapid (close to 100% desorption reached in a few minutes). However, the desorption of cadmium into the neutral food simulant depends on the initial cadmium concentration in the paper pulp, temperature and contact time. Surface response curves for each combination are presented.Temperature did not affect cadmium binding, but played a significant role for the desorption processes into the neutral food simulant.The proposed equations offer a good fitting of the experimental values, with p<0.001 and residuals within a factor of 3 for over 99% of the measured data. These models allow estimations of the expected exposure levels in consumers, on the basis of manufacture and use conditions. Linking the expected exposure with toxicity thresholds, such as the admissible daily intake (ADI), would allow a scientific assessment of the maximum acceptable cadmium levels in water–pulp liquors during manufacture and in the final paper pulp on the basic of the use patterns of each food packaging material. [Copyright &y& Elsevier]

The study of micro-objects, both inorganic and organic, which can be found associated to parchment or cellulose fibres of books and documents, or in the inks and the dirt, accumulated over the centuries between the pages, can unravel important information on the manufacture of the ancient documents, on their past vicissitudes or on the causes of aging and deterioration of the materials they contain. The results of a critical observation of micrometric objects and structures with a diagnostic or archaeological significance have in some cases been surprising. Apart from the curiosity that certain findings may or may not raise, what needs to be discussed is the fact that some chemical components, usually attributed to the manufacture of materials or the inks may instead have a particular origin and nature, and therefore lead, if not properly highlighted, to some erroneous diagnostics. Examples are given where the information obtained by means of scanning electron microscope imaging and Raman microscopy were coupled with dispersive X-ray microanalysis and Fourier Transform Infrared Spectroscopy. [ABSTRACT FROM AUTHOR]