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排序方式: 共有5729条查询结果,搜索用时 62 毫秒
1.
Bi Dongxue Sverbil Pavel P. Voinov Yury P. Wu Mengyuan 《Journal of Russian Laser Research》2021,42(6):671-676
Journal of Russian Laser Research - We discuss the use of high-pressure high-temperature (HPHT) diamonds for the determination of trace amounts of various Raman active substances. The amount of the... 相似文献
2.
Nováková Kateřina Hrdlička Vojtěch Navrátil Tomáš Vyskočil Vlastimil Barek Jiří 《Monatshefte für Chemie / Chemical Monthly》2015,146(5):761-769
Monatshefte für Chemie - Chemical Monthly - The voltammetric behavior of 5-nitroindazole was investigated at polished (p-AgSAE) and at mercury meniscus-modified (m-AgSAE) silver solid amalgam... 相似文献
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Mejía Hugo Fernando Giraldo Jiménez-Piqué Emilio Valdés Matías Procaccini Raúl Pellice Sergio 《Journal of Solid State Electrochemistry》2020,24(10):2451-2460
Journal of Solid State Electrochemistry - A novel material was developed using sol-gel chemistry and an environmental-friendly grafting process of clay nanoparticles. In a previous work of our... 相似文献
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J. Kudrna I. Pelant J. Štěpánek F. Trojánek P. Malý 《Applied Physics A: Materials Science & Processing》2002,74(2):253-256
We have studied ultra-fast carrier dynamics of photo-excited carriers in hydrogenated microcrystalline silicon prepared by
a very high frequency glow-discharge technique. We report on direct observation of two types of dynamics using selective photo-excitation
in picosecond pump and probe measurements. One type of the observed dynamics has been found to be independent of the sample
preparation, while the other reflects the relative weights of crystalline and amorphous fractions. We propose a simple rate-equation
model that describes the carrier dynamics in microcrystalline silicon in terms of the composition of those in Si microcrystallites
and in the a-Si:H tissue which surrounds the microcrystallites. The model without any fitting parameters reproduces the experimental
data very well when the dynamics are scaled with relative volume fractions as obtained from Raman spectra.
Received: 23 November 2000 / Accepted: 17 March 2001 / Published online: 23 May 2001 相似文献
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S. B. Ellis S. J. Kiehl W. S. Hughes K. Schwabe W. C. Gardiner H. L. Sanders H. Yoshimura Hanna Jablezynska-Jedrzewska J. Domański W. A. Dorfman P. Nylén Barbara Stone F. Hovorka W. C. Dearing E. Biilmann W. Kordatzki P. Wulff G. Florence A. Drilhon P. Szigeti O. Tomiček F. Poupě O. Redlich W. Stricks 《Analytical and bioanalytical chemistry》1937,111(2-4):94-104
9.
Dmitry S. Zimnitsky Tatiana L. Yurkshtovich Pavel M. Bychkovsky 《Journal of polymer science. Part A, Polymer chemistry》2004,42(19):4785-4791
Samples of oxidized cellulose (OC) with various carboxyl contents and degrees of crystallinity were obtained by the oxidation of native and mercerized cellulose with a solution of nitrogen(IV) oxide in CCl4. A detailed characterization of these OC samples was performed. The effect of oxidation conditions (concentration of N2O4 in the solution and oxidation time) and starting cellulose material on OC characteristics (carboxyl, carbonyl and nitrogen content, degree of crystallinity and polymerization, surface area and swelling, and acidic properties) was investigated. Reactivity in the oxidation process was higher in mercerized cellulose than in native cellulose. The action of dilute solutions (10–15%) of N2O4 did not affect the degree of crystallinity of cellulose samples. Under these conditions, the oxidation took place mainly in amorphous regions and on the surface of crystallites. Oxidation in a concentrated (40%) N2O4 solution led to the destruction of crystallites, which increased the surface area and swelling of cellulose in water. The surface area and the swelling of OC samples increased with a decrease in the index of crystallinity. The acidic properties of OC were shown to increase with an increase of swelling in water. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4785–4791, 2004 相似文献
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