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51.
D. P. Krut'ko M. V. Borzov A. V. Churakov D. A. Lemenovśkii O. A. Reutov 《Russian Chemical Bulletin》1998,47(11):2280-2285
ansa{·5,·5′-[1,1′-(1-silacyclopent-3-ene-1,1-diyl)bis(indenyl)]} dichlorozirconium (1a,b) was synthesized. The crystal structure ofmeso-[(1,4-CH2CH=CHCH2)Si(C9H6)2ZrCl2] (1b) was established by X-ray diffraction analysis. Photoinduced interconversion of the racemic (1a) andmeso forms was studied under various conditions. The photostationary state (rac: meso=55∶45) was established rapidly when solutions ofansa-zirconocene were irradiated with visible light.
Deceased
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2351–2356, November, 1998. 相似文献
52.
Development of hollow fiber‐supported liquid‐phase microextraction and HPLC‐DAD method for the determination of pyrethroid metabolites in human and rat urine
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Wielgomas Bartosz Wiśniewski Marcin Czarnowski Wojciech 《Biomedical chromatography : BMC》2014,28(5):708-716
A simple hollow fiber liquid‐phase microextraction method for the determination of synthetic pyrethroid metabolites, 3‐phenoxybenzoic acid and 4‐hydroxy‐3‐phenoxybenzoic acid, in human and rat urine was developed and validated. A polypropylene hollow fiber tightly fitted onto a Nylon rod and impregnated with organic solvent served as a disposable extraction device. Desorption of analytes was carried out in NaOH solution, analyzed further by gradient HPLC and diode array detection method. Important factors were identified using Taguchi OA16 (45) orthogonal array design and further optimized using univariate approach. The optimum method performance was observed when 1 mL of urine hydrolyzed with 0.2 mL of concentrated HCl was further supplemented with 100 mg of NaCl and extracted for 120 min into dihexyl ether immobilized in the pores of the hollow fiber. Metabolites were desorbed into 0.1 mL of 0.1 M NaOH for another 120 min. Limits of detection and quantitation of 15 and 50 ng/mL were obtained for both analytes. Relative standard deviations of 1.6–12.6% over the linear range (50–10,000 ng/mL, r > 0.9906) were observed. Intra‐ and inter‐day accuracies of the method ranged from 98.3 to 109.5% and from 93.3 to 110.9%, respectively. The optimized method was applied to the analysis of real urine samples collected from rats exposed orally to cypermethrin. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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We consider the motion of compressible viscous fluids around a rotating rigid obstacle when the velocity at infinity is non zero and parallel to the axis of rotation. We prove the existence of weak solution. 相似文献
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Stanisław Leśniak Adam M. Pieczonka Szymon Jarzyński Katarzyna Justyna Michał Rachwalski 《Tetrahedron: Asymmetry》2013,24(20):1341-1344
A straightforward synthesis of a series of new catalysts derived from N-triphenylmethyl-aziridine-2-carbohydrazides is described. The new compounds have been tested for the enantioselective addition of diethyl- and phenylethynylzinc to aryl and alkyl aldehydes, which afforded the corresponding chiral alcohols in high chemical yields (up to 92%) and with excellent ee’s of approximately 90%. 相似文献
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Piotr T. Chruściel Erwann Delay Paul Klinger Andreas Kriegl Peter W. Michor Armin Rainer 《Letters in Mathematical Physics》2018,108(9):2009-2030
We prove existence of large families of solutions of Einstein-complex scalar field equations with a negative cosmological constant, with a stationary or static metric and a time-periodic complex scalar field. 相似文献
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