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991.
The L1 subshell orbital electron capture probability PL1 in the decay of 33.4 y 207Bi to the 2339.89 keV level in 207Pb is measured to be 0.518 ± 0.081 (95% confidence) by a new method in which L1 subshell characteristic X-rays in the Lγ X-ray peak are observed in an Xγt coincidence mode with 1770.23 keV γ-rays. The value of PL2is 0.047 ± 0.015 (95% confidence). From these results a value of QEC = 39-8+21 keV is obtained for capture transitions to the 2339.89 keV level. The absence of K-capture to this level also is established by absence of K X-rays in coincidence with 1770.23 keV γ-rays. 相似文献
992.
993.
994.
We give some conditions on H and for the rooted product H() to be graceful. These conditions extend and unify previous results. 相似文献
995.
996.
The mononuclear structure of Zn[S2CN(Me)Cy)]2 features a tetrahedral zinc center defined by two chelating dithiocarbamate ligands. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
997.
The theory of atomic diffraction from a classical standing wave light field in the presence of spontaneous emission in the Raman-Nath regime was developed by Tanguy et al. [6]. We describe the basis of computationally efficient methods for performing calculations in this regime and show their agreement with recent experimental results of Gould et al. [4]. 相似文献
998.
Ming Tan 《Journal of multivariate analysis》1991,38(2)
The problem of finding classes of estimators which improve upon the usual (e.g., ML, LS) estimator of the parameter matrix in the GMANOVA model under (matrix) quadratic loss is considered. Classes of improved estimators are obtained via combining integration-by-parts methods for normal and Wishart distributions. Also considered is the application of control variates to achieve better efficiency in multipopulation multivariate simulation studies. 相似文献
999.
B. P. Liu X. C. Lv Z. C. Tan Z. H. Zhang Q. Shi L. N. Yang J. Xing L. X. Sun T. Zhang 《Journal of Thermal Analysis and Calorimetry》2007,89(1):283-287
The molar heat capacity, C
p,m, of a complex of holmium chloride coordinated with L-aspartic acid, Ho(Asp)Cl2·6H2O, was measured from 80 to 397 K with an automated adiabatic calorimeter. The thermodynamic functions H
T-H
298.15 and S
T-S
298.15 were derived from 80 to 395 K with temperature interval of 5 K. The thermal stability of the complex was investigated by
differential scanning calorimeter (DSC) and thermogravimetric (TG) technique, and the mechanism of thermal decomposing of
the complex was determined based on the structure and the thermal analysis experiment. 相似文献
1000.
Photochemical cycloaddition of cyclopentene with enone esters containing different chiral auxiliaries yielded anti and syn adducts and in good yield and with moderate to high (79%) enantiomeric excesses. 相似文献