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81.
82.
Surendra Singh Saibal Basu M. Vedpathak R.H. Kodama R. Chitra Y. Goud 《Applied Surface Science》2005,240(1-4):251-259
Metal-semiconductor multilayers are interesting, artificial structures as prospective candidates for spin injection devices. A Fe–Ge multilayer sample with very thin individual layers (few crystallographic planes) has been deposited by sputtering on Si[1 0 0] substrate. We have characterized the structure of this multilayer sample using X-ray diffraction, X-ray reflectometry and neutron reflectometry. The magnetic moment density in the ferromagnetic Fe layer has been obtained by polarized neutron reflectometry and the bulk magnetic behavior of the thin film by SQUID magnetometer measurements. We found that the film is a soft ferromagnet at room temperature with a substantially reduced magnetic moment of the Fe atoms. 相似文献
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86.
C. Gundu Rao Surendra U. Kulkarni Herbert C. Brown 《Journal of organometallic chemistry》1979,172(2):C20-C22
Organoboranes derived from terminal olefins are oxidized by pyridinium chlorochromate to aldehydes in good yields. 相似文献
87.
Shiva P. Singh Surendra S. Parmar Sylvia A. Farnum Virgil I. Stenberg 《Journal of heterocyclic chemistry》1978,15(7):1083-1087
The natural abundance carbon-13 nuclear magnetic resonance spectra of diazepam, clonazepam, flurazepam and chlordiazepoxide were recorded in suitable solvent using the Fourier transform technique on a JEOL FX-60 spectrometer. The relaxation time (T1) of these compounds were also measured. The chemical shift of the various carbon resonances have been assigned on the basis of chemical shift theory, multiplicity generated in single-frequency off-resonance decoupled spectra, relaxation time and the chemical shifts of the model compounds. 相似文献
88.
Rataboul F Zapf A Jackstell R Harkal S Riermeier T Monsees A Dingerdissen U Beller M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(12):2983-2990
The synthesis and application of monodentate N-substituted heteroarylphosphines is described. In general, the ligands are conveniently prepared by selective metallation at the 2-position of the respective N-substituted heterocycle (pyrrole, indole) by using n-butyllithium/tetramethylethylenediamine (TMEDA) followed by quenching with dialkyl- or diarylchlorophosphines. Of the different ligands prepared, the new dialkyl-2-(N-arylindolyl)phosphines (cataCXium P) perform excellently in the palladium-catalyzed amination of aryl and heteroaryl chlorides. Coupling of both activated and deactivated chloroarenes proceeds under mild conditions (room temperature to 60 degrees C). By using optimized conditions remarkable catalyst productivity (total turnover number, TON, up to 8000) and activity (turnover frequency, TOF=14000 h(-1) at 75% conversion) are observed. 相似文献
89.
Chaki NK Sudrik SG Sonawane HR Vijayamohanan K 《Chemical communications (Cambridge, England)》2002,(1):76-77
A simple and reproducible single phase preparation of 2.5 nm silver nanoclusters is described using silver benzoate along with triethylamine (TEA) and dodecanethiol (DDT); these spontaneously self-assemble to a two-dimensional array whereas in the absence of thiol only polydispersed nanoclusters are obtained. 相似文献
90.
Sensor-embedded products (SEPs) eliminate a majority of uncertainties involved in product recovery by providing item-based life-cycle information. This information includes the content of each product and component conditions, and enables the estimation of remaining useful life of the components. Once the data on the products are captured, it is possible to make optimal recovery decisions without any preliminary disassembly or inspection operations. 相似文献