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971.
972.
973.
974.
The state-of-the art of databases in materials science, understood as ordered and stored information, is discussed and the
outlook for their development is deliberated. The text is divided in sections dealing with the glory, misery and future vision
of databases, thermal analysis having its own comment.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
975.
Dieter Freitag Gerd Fengler Leo Morbitzer 《Angewandte Chemie (International ed. in English)》1991,30(12):1598-1610
Polycarbonate together with the acrylonitrile/butadiene/styrene copolymers, and the poly amides constitute the leading groups of engineering thermoplastics; for polycarbonate in particular, continued dynamic growth is prophesized. The underlying reason for this lies not only in its outstanding combination of technical properties and excellent price/performance balance, but also in the chemical and physical potential inherent in the basic structure of polycarbonate. The following review demonstrates with examples how this potential can be used in the development of new polycarbonates through the incorporation of alternative monomers, changes in the linear structure, end group variation, addition of special additives, and blending. The main emphasis of this articles lies in the development of polycarbonates resistant to high temperature, with a good balance of technologically valuable properties. For scientific and practical interests a new criterion is offered for polycarbonates having both high-temperature stability and impact strength. “One must not only make a discovery, but also realize that a discovery has been made.” Hermann Schnell [1] 相似文献
976.
Georg Gliemeroth Karl-Heinz Mader 《Angewandte Chemie (International ed. in English)》1970,9(6):434-445
Phototropic glass darkens on exposure to light and returns to its original state in the absence of light. The most extensively investigated of these glasses contain grains of silver halide having sizes > 50 Å. A discussion of theoretical principles is followed by a review of the very broad scope of the phenomenon. 相似文献
977.
Axel Hartmann Edward Sangmeister 《Angewandte Chemie (International ed. in English)》1972,11(7):620-629
The puzzle we have to solve is: How did prehistoric man live? Archeologists and scientists, chemists and prehistorians have now joined forces in applying much imagination and pains taking effort to the search for a solution. Some of the fruits of their cooperation are presented in this progress report. 相似文献
978.
Gerhard Winter 《Angewandte Chemie (International ed. in English)》1972,11(9):751-760
This progress report ends with the sentence: In the opinion of many experts, we are entering an “age of inorganic fibers”. An attempt is made in the article to outline the present stage of development and the outlook for one of the most interesting fields of modern materials science. 相似文献
979.
980.
High-resolution magic angle spinning (HRMAS) NMR is probably the most apt NMR method to analyze complex materials involving a solid phase, e.g. foodstuffs. We present here an HRMAS analysis of grated cheese (Parmigiano Reggiano). A full NMR characterization of this cheese allows the identification of the presence of fatty acids (saturated and unsaturated), amino acids and other small organic molecules. Since the presence and relative concentration of these molecules have previously been shown to correlate with organoleptic, origin and age characterization, HRMAS NMR of cheese is likely to provide a good complimentary tool for the analysis of this food material. 相似文献