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S. A. Waksman K. R. Stevens A. Rippel G. Behr H. Wiangke Pfeiffer R. R. Le G. Worsley und F. J. Nutman 《Fresenius' Journal of Analytical Chemistry》1934,96(3-4):151-155
Ohne Zusammenfassung 相似文献
955.
R. F. Le Guyon R. M. May W. M. Mc Nabb A. v. Endrédy H. H. Willard A. W. Boldyreff G. E. F. Lundell J. I. Hoffman W. Blum C. M. Johnson O. Kuhnt R. Ariano R. P. Hudson F. Graziani L. Losana H. Burton-Smith W. F. Pond L. E. Pitzer B. Salkin K. Hinsberg D. Laszlo und G. Schikorr 《Fresenius' Journal of Analytical Chemistry》1931,85(7-8):286-303
Ohne Zusammenfassung 相似文献
956.
Alexandre Lumbroso Isabelle Beaudet Thierry Besson Erwan Le Grognec 《Tetrahedron》2009,65(45):9180-45
An efficient and reproducible synthesis of various α-ethoxycarbamates is described via a microwave heating mode. Compared to the thermal process, the microwave dielectric heating induces a dramatic reduction of the reaction time and the improvement of the yields. The reaction is general since applicable to aromatic and aliphatic aldehydes with various primary amines. Several examples involving chiral aldehydes have also been considered. 相似文献
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The kinetic and mechanism of the reaction Cl + HO2 → products (1) have been studied in the temperature range 230–360 K and at total pressure of 1 Torr of helium using the discharge‐flow mass spectrometric method. The following Arrhenius expression for the total rate constant was obtained either from the kinetics of HO2 consumption in excess of Cl atoms or from the kinetics of Cl in excess of HO2: k1 = (3.8 ± 1.2) × 10?11 exp[(40 ± 90)/T] cm3 molecule?1 s?1, where uncertainties are 95% confidence limits. The temperature‐independent value of k1 = (4.4 ± 0.6) × 10?11 cm3 molecule?1 s?1 at T = 230–360 K, which can be recommended from this study, agrees well with most recent studies and current recommendations. Both OH and ClO were detected as the products of reaction (1) and the rate constant for the channel forming these species, Cl + HO2 → OH + ClO (1b), has been determined: k1b = (8.6 ± 3.2) × 10?11 exp[?(660 ± 100)/T] cm3 molecule?1 s?1 (with k1b = (9.4 ± 1.9) × 10?12 cm3 molecule?1 s?1 at T = 298 K), where uncertainties represent 95% confidence limits. © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33: 317–327, 2001 相似文献
959.
Xinyu Wei Weiyin Gu Le Li Xiaobo Shen Jung‐Keun Kim Thomas P. Russell 《Journal of Polymer Science.Polymer Physics》2013,51(1):78-85
We reported the synthesis and morphology of a novel alkyne‐functionalized diblock copolymer (di‐BCP) poly(methyl methacrylate‐random‐propargyl methacrylate)‐block‐poly(4‐bromostyrene). The di‐BCPs were synthesized by atom transfer radical polymerization and postpolymerization deprotection, with good control over molecular weight and polydispersity index. Microphase separation in bulk di‐BCPs was confirmed by thermal analysis, small‐angle X‐ray scattering, and transmission electron microscopy. Microphase‐separated morphologies were also observed in thin films, and the orientation of the microdomains can be conveniently controlled by annealing under different solvents. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献
960.
Michail I. Alymov Nikolai M. Rubtsov Boris S. Seplyarskii Victor A. Zelensky Alexey B. Ankudinov Georgii I. Tsvetkov Victor I. Chernysh 《Mendeleev Communications》2018,28(4):447-449
It was shown that the synthesis of Cu nanopowder by thermal decomposition afforded chemically purer (without oxides) and finer (specific surface value ~45 m2 g?1) product than the synthesis by chemical reduction. The latter method leads to pyrophoric nanopowders containing detectable amounts of copper oxides. 相似文献