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排序方式: 共有1798条查询结果,搜索用时 15 毫秒
991.
992.
Lead contents in geochemical rock standards of the Geological Survey of Japan and U.S. Geological Survey, were determined with coefficients of variation less than 5%. After dissolution of the rock by hydrofluoric and nitric acids, and spiking with 212Pb, lead purified by extraction with dithizone, appropriate corrections being applied to the final results. 相似文献
993.
994.
N. Kan K. Sakamoto K. Shiraishi 《The European Physical Journal C - Particles and Fields》2003,28(3):425-430
We calculate the effective potential for the WLPNGB in a world with a circular latticized extra dimension. The mass of the
Wilson line pseudo-Nambu-Goldstone boson (WLPNGB) is calculated from the one-loop quantum effect of scalar fields at zero
and finite temperature. We show that a series expansion by the modified Bessel functions is useful to calculate the one-loop
effective potentials.
Received: 24 January 2003 / Published online: 14 April 2003
RID="a"
ID="a" e-mail: b1834@sty.cc.yamaguchi-u.ac.jp
RID="b"
ID="b" e-mail: b1795@sty.cc.yamaguchi-u.ac.jp
RID="c"
ID="c" e-mail: shiraish@po.cc.yamaguchi-u.ac.jp 相似文献
995.
基于麦克斯韦方程,本文对岩爆过程中产生的电磁辐射在煤层、岩石中的传播规律进行了理论计算.分析与研究结果显示:一方面,岩爆过程中产生的电磁辐射信号符合麦克斯韦方程;另一方面,数值模拟破裂过程电磁辐射在煤层、岩石中的传播时可将电磁辐射产生源理想化为水平电偶极子和水平磁偶极子的叠加;并得出了电磁辐射源产生的场在煤层、岩石中空间分布的解析计算式.麦克斯韦方程的应用对于岩爆等动力灾害预测的电磁辐射监测仪的研制和定向定位监测具有重要的理论和实际意义. 相似文献
996.
Haiyong Chen Hongliang Lu Yanguang Nie Jiahua Zhang Mingzhe Zhang Quanqin Dai Shiyong Gao Shihai Kan Dongmei Li Guangtian Zou 《Physics letters. A》2007
We have fabricated sharp-tipped Te nanowires on a NaNO2 nanoparticles substrate by vapor deposition method. These nanowires are parallel or perpendicular to c-axis of hexagonal Te depending on the source temperature. We think the sharp-tip can efficiently reduce the energy of adsorbed atoms, leading to favorable growth along its direction. 相似文献
997.
M.L. Fisher B.J. Lageweg J.K. Lenstra A.H.G.Rinnooy Kan 《Discrete Applied Mathematics》1983,5(1):65-75
Surrogate duality bounds for the job shop scheduling problem are obtained by replacing certain constraints by their weighted sum and strengthening the aggregate constraint by iterating over all possible weights. The constraints successively considered for this purpose are the capacity constraints on the machines and the precedence constraints determining the machine order for each job. The resulting relaxations are investigated from a theoretical and a computational point of view. 相似文献
998.
999.
James J. Griffin Maria Dworzecka Peter C. Lichtner Kit-Keung Kan 《Physics letters. [Part B]》1980,93(3):235-239
A single determinantal TDHF reaction theory structurally analogous with the S-matrix Schrödinger theory is constructed. It involves time averaging in an essentail way, displays the interpretatively crucial properties of asymptoticity and channel specificity, and excludes the effects of multi-channel spurious cross channel correlations. 相似文献
1000.
S. Tran-Dinh J. M. Neumann T. Huynh-Dinh J. Igolen S. K. Kan 《Magnetic resonance in chemistry : MRC》1982,18(3):148-152
A general method for the assignment of DNA fragment proton resonances, especially for the sugar protons, has been presented and used to interpret the 400 MHz proton spectra of dApTpGpT and dApCpApTpGpT in neutral aqueous solution. Only fine splittings of about 3 Hz are observed in the H-2″ resonances, and the total splitting is larger for the H-2′ (≈29 Hz) than for the H-2″ (22–23 Hz) multiplets. The purine and pyrimidine resonances can be distinguished on the basis of the H-2″ and H-2″ chemical shifts. The resonances of the H-2′ and H-2″ protons (above and below the sugar plane, respectively) of dA and dG exhibit chemical shifts of 2.65—2.80 ppm, while those of dC and dT residues are located at higher fields between 1.95 and 2.40 ppm. At high temperature (≥60°C), δH-2′>YδH-2″ for the purine family, while δH-2′ « δH-2″ in the case of the pyrimidine family. Except for the terminal residue, the H-3′ resonances of dA and dG are located at lower fields compared with those of the dC and dT residues. The same is true for the H-4′ resonances. In general δA1′>δG1′ and in the case of self complementary duplexes the H-1′ and H-2′ chemical shift variations versus temperature are found to be larger for the dC than for the dT residues. 相似文献