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The electronic structure around the ideal 3d transition metal impurities at substitutional site of germanium is calculated self-consistently within the local density formalism. Chemical trend of 3d impuritiy levels caused by the strong p-d hybridization, is revealed in the case of non-magnetic state. The magnetic state of the iron impurity is also presented and the local magnetic moment experienced by iron impurity is calculated to be 3.72μB. 相似文献
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12 bile acids, including 1 beta-hydroxylated and unsaturated bile acids, have been quantified by capillary gas chromatography/negative ion chemical ionization mass spectrometry, using the trimethylsilyl(TMS) ether derivatives of bile acid pentafluorobenzyl(PFB) esters. The analysis time is 12 min and the minimum measurable amount is 100 fg for each bile acid. Bile acids in 200 microL of serum and 50 microL of urine from healthy human adults were measured. These small sample sizes enhance the practicality of using this method as a screening test for bile acids in the serum and urine of human infants, where small sample size is a major problem. 相似文献
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Seiko Nakagawa Mitsumasa Taguchi Koichi Hirota Takeshi Murakami 《Radiation Physics and Chemistry》2010,79(8):890-893
Hydroxymaleimide was irradiated in N2-saturated 2-propanol solutions by high-energy heavy ions over a wide range of LET values. The differential G-values of the degradation of hydroxymaleimide by irradiation with the heavier ions were lower than those of the lighter ions for the same LET value. An opposite result obtained in the air-saturated system. The degradation efficiency was 1.5 times higher, when the dose rate was 1/10 times lower. When irradiated at an LET value lower than 8 eV/nm, the G-values converged to a value less than that obtained by γ-irradiation. 相似文献
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The decaying process of a large surface potential of as-deposited Alq3 film was analyzed with consideration of electrostatic energies stored in the film. The analysis includes the cooperative molecular field effect and it shows that the derived equilibrium condition of dipolar films with electron traps supports the concept of the alignment of Fermi-level of metal and surface Fermi-level of dipolar films. The potential decay of Alq3 films on Al electrodes by photo-exposure is explained due to detrapping of trapped electrons that are immediately transported to the injected electrodes along with the disordering of polar structure of Alq3 films. 相似文献
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S. Nakajima M. Kikuchi Y. Syono K. Nagase T. Oku N. Kobayashi D. Shindo K. Hiraga 《Physica C: Superconductivity and its Applications》1990,170(5-6):443-447
The Tc and oxygen content of TlBa2CaCu2Oy have been investigated by quenching experiments, in which the heat-treated samples were dropped into liquid nitrogen. The oxygen loss, v, of TlBa2CaCu2Oyo − v was determined by thermogravimetry in a nitrogen atmosphere using an oxygen-annealed specimen of TlBa2CaCu2Oyo and also by measurements of the weight differences before and after quenching. Tc increased from 80 K of the oxygen-annealed specimen up to about 110 K with increasing oxygen loss up to v = 0.035 by annealing at 500°C in a nitrogen atmosphere. Judging from the high Tc above 110 K achieved by a small oxygen loss about v = 0.035, the as-sintered oxygen-annealed TlBa2CaCu2Oyo specimen was in the over-doping state and probably has an oxygen vacancy of 7 − yo0. 相似文献
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