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991.
H. Pohl H. Kurtenacker H. Schmidt G. Denk K. Brodersen H. Freytag und J. Plank 《Fresenius' Journal of Analytical Chemistry》1955,147(2):138-141
Ohne Zusammenfassung 相似文献
992.
Em. Schmidt 《Fresenius' Journal of Analytical Chemistry》1875,14(1):204-205
Ohne Zusammenfassung 相似文献
993.
Aleksandar G. Ostrogorsky
Frank Mosel
Michael T. Schmidt
《Journal of Crystal Growth》1991,110(4):950-954Two 1.35 kg, 5.8 cm diameter Sn-1% Bi specimens were solidified using the submerged heater method (SHM). The distribution of solute was found to be uniform axially, indicating that diffusion-controlled steady-state segregation, though to be unattainable on earth because of the gravity induced interference, was achieved. 相似文献
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Christian Heller Niklas Pucher Bernhard Seidl Kadiriye Kalinyaprak‐Icten Gerald Ullrich Ladislav Kuna Valentin Satzinger Volker Schmidt Helga C. Lichtenegger Jürgen Stampfl Robert Liska 《Journal of polymer science. Part A, Polymer chemistry》2007,45(15):3280-3291
Intrigued by the good performance of 1,5‐diphenylpenta‐1,4‐diyn‐3‐one ( DPD ) as photoinitiator for radical polymerization we prepared and investigated several donor substituted derivatives. UV‐Vis spectroscopy revealed a gradual red‐shift of λmax and higher extinction in the order of the donor capability. A methoxy‐substituted derivative ( O‐DPD ) exhibited significant photoinitiation activity in photo‐DSC experiments. Steady state photolysis experiments showed decreased decomposition rates with increasing donor capability. A dimethylamino derivative N‐DPD was even photostable under these conditions. Because of to the D‐π‐A‐π‐D system of these compounds two‐photon induced 3D photopolymerization experiments were performed and N‐DPD showed outstanding performance compared to often applied single photon initiators. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3280–3291, 2007 相似文献
998.
Klaus D. Schmidt 《Bl?tter der DGVFM》1997,23(2):245-247
999.
The curriculum, teaching, and assessment Standards of the National Council of Teachers of Mathematics advocate the use of various assessment techniques in mathematics, K-12. Practitioners from 35 school districts in two regions of a midwestern state completed a questionnaire and reported information about their assessment practices, reporting methods, and other issues that affect change in mathematics. The results of the survey suggest that current reporting practices are limiting the use of alternative classroom assessment practices. Delays in the use of alternative mathematics assessment practice can probably be expected until the reporting systems used in school districts become consistent with the assessment systems and teachers participate in ongoing professional development programs to learn more about alternative assessment practices. 相似文献
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M. Jurić Dj. Krmpotić O. Adamović V. Gerc L. Rak J. Lory D. Schune Tsai-Chü B. Willot K. P. Hong C. O. Kim S. N. Kim K. A. Moon R. Schmidt I. Otterlund G. Baumann M. Lopez Agüera R. Niembro A. Ruiz E. Villa 《Zeitschrift fur Physik C Particles and Fields》1984,22(2):131-136
Experimental data are presented on charged particle multiplicities production in interactions of 300 GeV/c negative poins with emulsion nuclei. Correlations were established and the obtained parameters of multiplicity distributions compared with those obtained from proton-nucleus interaction data at 300 GeV/c. 相似文献