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951.
LCAO-MO-SCF calculations are reported for the different stereoisomers of the Mo(CO)4(CH2)2 and Mo(CO)4[C(NH2)2]2 systems. The substitution of the hydrogen atoms by the amino groups in the carbene ligands leads to an almost zero rotational barrier. Steric interactions are therefore expected to govern the barrier for diaminocarbene ligands which are more bulky than C(NH2)2. The rotational isomerism in thesebis carbene MoL4 systems is also discussed in connection with the isolobal analogy between CH2 and C2H4. 相似文献
952.
Jun'ichiro Miura Masaru Yamada Yoshiharu Nakamura 《Fresenius' Journal of Analytical Chemistry》1985,321(6):575-577
Summary A selective preconcentration technique for copper using the kerateine gel is described. The gel is prepared by partial oxidation of kerateine which is obtained by reducing the disulphide bonds of wool fiber. Copper is selectively adsorbed on the gel at pH 3.5. It is eluted with 3 M hydrochloric acid and is determined by atomic-absorption spectrometry. This method has been applied to the determination of copper in river water.
Selektive Anreicherung von Kupfer aus wäßriger Lösung mit Hilfe von Keratein-Gel
Zusammenfassung Ein selektives Anreicherungsverfahren für Kupfer mit Hilfe von Keratein-Gel wurde ausgearbeitet. Das Gel wird durch teilweise Oxidation von Keratein hergestellt, das aus Wollfaser durch Reduktion der Disulfidbindungen gewonnen wird. Kupfer wird bei pH 3,5 selektiv an diesem Gel adsorbiert und kann mit 3 M Salzsäure eluiert werden. Die Bestimmung erfolgt mit Hilfe der AAS. Das Verfahren kann zur Kupferbestimmung in Flußwasser angewendet werden.相似文献
953.
Sulphate conjugation of p-nitrophenol (p-NP) in the liver and platelet cytosol of guinea pigs, rabbits and dogs were studied. The dependency of phenol sulphotransferase (PST) activity on p-NP concentration in the liver of guinea pigs and rabbits and in the platelets of guinea pigs were similar to that reported for the liver (Mizuma et al., J. Pharmacobio-Dyn., 6, 851 (1983)) and platelets (Nakamura et al., J. Pharm. Pharmacol., 42, 207 (1990)) of rats. There was one peak of PST activity on p-NP at the concentration of 1 to 10 microM, and the PST activity was increased again with an increase of p-NP concentration above the original concentration. On the other hand, a peak in PST activity on p-NP at the concentration of 1 to 10 microM was not observed in the platelets of rabbits and dogs. These results indicated species and organ differences in PST activity on p-NP in liver and platelets. The biphasic activities of the PST and p-NP in platelets and liver of rat and guinea pig were similar to that reported in humans (Reiter et al., Naunyn-Schmiedeberg's Arch. Pharmacol., 324, 140 (1983)). 相似文献
954.
G.M. Luke K. Kojima M. Larkin J. Merrin B. Nachumi Y.J. Uemura Y. Nakamura S. Uchida M. Crawford 《Hyperfine Interactions》1997,105(1-4):113-117
We present μSR experiments on La2-x Bax CuO4 and La1.6-x Nd0.4 Srx CuO4 for x=0.125. Both of these materials order magnetically with TN\approx30\ K, while a superconducting sample of La1.4 Nd0.4 Sr0.2 CuO4 showed no evidence for static copper moments. Our results support the conclusion that the so‐called “1/8” anomaly in La2-x Bax CuO4 is a result of static (pinned) charge segregation.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
955.
N. Aoi K. Yoneda H. Miyatake H. Ogawa Y. Yamamoto E. Ideguchi T. Kishida T. Nakamura M. Notani H. Sakurai T. Teranishi H. Wu S. S. Yamamoto Y. Watanabe A. Yoshida M. Ishihara 《Zeitschrift für Physik A Hadrons and Nuclei》1997,358(2):253-255
Experimental studies of β-decay measurements of the neutron drip line nuclei 11Li and 14Be are presented. β- decay schemes of these nuclei are determined by measuring β-rays, delayed neutrons and γ-rays in triple coincidence. The decay schemes of both 11Li and 14Be associated with single neutron emission are unambiguously determined. New levels in their daughter nuclei, 11Be and 14B, are found. In addition, the deduced level scheme of 14B indicates the lowering of 2s 1/2 single neutron orbital with respect to 1p 1/2 orbital in the N=9 isotones. Such behavior is known to exist in N=7. 相似文献
956.
M. Forsthuber H. Nakamura M. Shigal E. Bauer 《Zeitschrift für Physik B Condensed Matter》1997,100(3):395-400
CePd2Ga3, a Kondo lattice exhibiting ferromagnetic order below T C = 6.3 K, has been studied using Ga NMR technique. Measurements of the magnetic susceptibility on an oriented sample proved the strong anisotropy of this quantity, whose major component is in the basal plane. From the analysis of NMR spectra of differently oriented samples, the quadrupole parameters and the temperature-dependent anisotropic Knight-shift have been determined. While the anisotropy of the susceptibility can sufficiently account for the axial anisotropy of the 71Ga Knight shift, the in-plane anisotropy of the shift points towards dipolar effects enhanced by hybridization of the Ce-4f and Ga-s electrons. 相似文献
957.
Y Inouye Y Tokutake J Kunihara T Yoshida T Yamase A Nakata S Nakamura 《Chemical & pharmaceutical bulletin》1992,40(3):805-807
958.
M. Yosoi H. Akimune I. Daito H. Ejiri H. Fujimura M. Fujiwara K. Hara K. Y. Hara T. Ishikawa M. Itoh Y. Itow T. Kawabata K. Kobayashi M. Nakamura T. Noro E. Obayashi H. Sakaguchi Y. Sakemi M. Shiozawa H. Takeda T. Taki A. Tamii H. Toyokawa N. Tsukahara M. Uchida T. Yamada Y. Yasuda H. P. Yoshida R. G. T. Zegers 《Physics of Atomic Nuclei》2004,67(10):1810-1817
Decay particles from the s-hole states in 11B and 15N have been measured in coincidence with the quasifree 12C(p, 2p) and 16O(p, 2p) reactions at E p =392 MeV. Triton decay is found to be dominant for the 11B(s-hole) state and also found to be larger than α decay for the 15N(s-hole) state despite its smaller Q value compared to α decay. Measured decay branching ratios are discussed in comparison with the results of statistical-model, SU(3)-model, and shell-model calculations. The energy spectra around the s-hole states in both 11B and 15N exhibit some bumplike structures, which can be qualitatively explained by recent shell-model calculations for both nuclei. 相似文献
959.
960.
Partially supported by NSF Grant DMS-9123742 相似文献