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991.
992.
X. H. Liu M. Sun J. J. Yue Y. X. Yin X. L. Liu F. M. Miao 《Journal of Molecular Structure》2003,620(2-3):227-230
In this paper, we carried out a theoretical study on the active site structures of the Mn-SOD with ab initio Hartree–Fock SCF method, and analyzed the molecular orbital energies, charges and atomic orbital contribution to the frontier molecular orbital. 相似文献
993.
Ricardo Fierro James C. W. Chien Marvin D. Rausch 《Journal of polymer science. Part A, Polymer chemistry》1994,32(15):2817-2824
Racemic isopropylidene (1-η5-cyclopentadienyl)(1-η5-indenyl) dichlorozirconium and the 3-methylindenyl derivative have been synthesized and characterized. These precursors activated with methylaluminoxane produce poly(propylene) with hemiisotactic microstructures. © 1994 John Wiley & Sons, Inc. 相似文献
994.
995.
996.
[reaction: see text] The decarboxylative photocyclization of potassium 2-azabicyclo[3.3.0]octanoate ethylene-linked to phthalimide leads to a mixture of two diastereoisomeric products. The overall noninduced diastereoselectivity is remarkably high, indicating a preference of spin-orbit coupling controlled 1,7-biradical combination process. Memory of chirality vanished due to free rotation about the connecting spacer bonds. 相似文献
997.
Automated separation and measurement of radioxenon for the Comprehensive Test Ban Treaty 总被引:2,自引:0,他引:2
T. W. Bowyer K. H. Abel C. W. Hubbard A. D. McKinnon M. E. Panisko R. W. Perkins P. L. Reeder R. C. Thompson R. A. Warner 《Journal of Radioanalytical and Nuclear Chemistry》1998,235(1-2):77-82
A fully automatic radioxenon sampler/analyzer (ARSA) has been developed and demonstrated for the collection and quantitative
measurement of the four xenon radionuclides,131mXe(11.9 d),133mXe(2.2 d),133Xe(5.2 d), and135Xe(9.1 hr), in the atmosphere. These radionuclides are important signatures in monitoring for compliance to a Comprehensive
Test Ban Treaty (CTBT). Activity ratios of these radionuclides permit source attribution. Xenon, continuously and automatically
separated from the atmosphere, is automatically analyzed by electron-photon coincidence spectrometry providing a lower limit
of detection of about 100 μBq/m3. The demonstrated detection limit is about 100 times better than achievable with reported laboratory-based procedures for
the short-time collection intervals of interest. 相似文献
998.
999.
M. Ebihara Y. S. Chung W. Chueinta B.-F. Ni T. Otoshi Y. Oura F. L. Santos F. Sasajima Sutisna A. K. B. H. Wood 《Journal of Radioanalytical and Nuclear Chemistry》2006,269(2):259-266
Summary Seven Asian countries have been collaborating in collecting airborne particulate matter (APM) in their individual countries
and analyzing them by neutron activation analysis as a common analytical tool. APM samples were collected into two fractions
of fine and coarse grains (PM2 and PM2-10, respectively). Analytical data were compared from several viewpoints such as particulate
sizes, locality of sampling sites (either urban or rural) and geographical location of participating countries. Chemical composition
and their monthly variations as well as mass concentrations appear to be highly characteristic for individual sampling sites,
suggesting that NAA data are suitable for evaluating the air quality in each site. 相似文献
1000.
Cs. Vértes I. Czakó-Nagy W. Meisel M. Kolonits F. Horkai A. Vértes 《Journal of Radioanalytical and Nuclear Chemistry》1990,144(3):179-187
A stacking Mössbauer technique, MMS has been applied for studying thin surface layers. The surface layers formed on the57Fe film in aqueous solutions of corrosion inhibitors, such as zinc phosphate and barium metaborate, and in distilled water was studied by this method. It has been found that the corrosion is much slower in the presence of zinc phosphate and barium metaborate. XPS analysis suggests the formation of a mixed iron zinc phosphate on the surface of the57Fe film after corrosion in a zinc phosphate solution. 相似文献