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991.
季铵酚离子在水/硝基苯界面的转移 总被引:1,自引:0,他引:1
油/水界面上的电化学研究是近年来电化学研究中的一个新领域,对膜电化学的发展具有重要意义。目前研究油/水界面电化学中普遍使用循环伏安(CV)法和循环线扫电流计时电位(CLC)法。有关抗生素在油/水界面的转移已有报导,本文用CLC法和CV法对肌肉松弛剂季铵酚离子在水/硝基苯界面的转移行为进行了研究。 所用三碘季铵酚为中国科学院生物化学研究所生产的化学试剂,其他试剂及仪器均与前文相同 相似文献
992.
993.
The direct current comparator resistance bridge, Model 9975, manufactured by Guildline Instruments, Inc., which permits electrical
resistance measurements up to eight digits, has been fully automated. Details of this automation are described in this paper.
The performance of the automated bridge is demonstrated with applications to electrical resistivity studies on some metallic
alloys. 相似文献
994.
It is well known that an inverse problem of biomagnetic imaging is generally ill-posed. Recently several attempts using biocoherence have been reported, but the ill-condition is not considered in these previous methods. If the conventional reconstruction formula is under the ill-condition, the reconstruction problem is also ill-posed and the ill-posedness cannot be improved. In this paper, we propose an approach to estimate the location of current sources under the condition that sources of different positions have little or weak correlation. Our method is based on a well-known regularization method, the truncated SVD method. Compared with the conventional method, our technique allows accurate determination of the location of current sources because it improves the ill-posedness of the inverse problem. We carried out computer simulations using the half-space conducting model and confirmed the effectiveness of our method. 相似文献
995.
Pavel Vagner Martin Moko Radoslav Nmeth Lucas Wagner Lubos Mitas 《Physica E: Low-dimensional Systems and Nanostructures》2006,32(1-2):350
We calculate the persistent current of interacting spinless electrons in a one-dimensional ring containing a single δ barrier. We use the self-consistent Hartree–Fock method and the quantum Monte Carlo method which gives fully correlated solutions. Our Hartree–Fock method treats the non-local Fock term in a local approximation and also exactly (if the ring is not too large). Treating the Fock term exactly we attempt to support our previous Hartree–Fock result obtained in the local approximation, in particular the persistent current behaving like I∝L-1-α, where L is the ring length and α>0 is the power depending only on the electron–electron interaction. Finally, we use the Hartree–Fock solutions as an input for our quantum Monte Carlo calculation. The Monte Carlo results exhibit only small quantitative differences from the Hartree–Fock results. 相似文献
996.
研究了用控制电位库仑法测定银、砷、汞、铜单元素标准溶液(1000ug/mL)中离子的含量,进行了控制电位、支持电解质种类等条件的选择,使得测定背景电流小,测定精度优于0.1%,并对样品进行了均匀性、稳定性检验。 相似文献
997.
关于RLC电路谐振特性曲线的对称性问题 总被引:3,自引:0,他引:3
通过引入不对称因子δ从理论上讨论了RLC谐振回路的谐振曲线相对于谐振频率的牟称性问题,计算表明,在低Q值下谐振曲线是不对称的,为使整条曲线具的近似的对称特性,要求回路的Q〉100。 相似文献
998.
Parshant Batham S B Roy Shailendra Kumar A K Pradhan A K Grover P Chaddah Ram Prasad N C Soni 《Pramana》1995,45(3):261-269
Results are presented for study of nonlinear magnetization of a sintered YBa2Cu3O7−y pellet of different thickness of a sample subjected to very low magnetic field. On cooling the sample belowT
c in zero field a change, in the oscillatory structure of harmonics in increasing dc field is observed in very low ac magnetic
field. The effect of finiteness of the sample on the oscillatory structure and on the hysteresis of harmonics is also studied.
The results are explained qualitatively. 相似文献
999.
R E Marshak 《Pramana》1988,31(1):9-39
This retrospective paper traces the conceptual evolution of two theories in which the author was involved—the two-meson theory
(with H A Bethe) in 1947 and the universal (V-A) theory of weak interactions (with E C G Sudarshan) in 1957—into the present-day standard model of particle interactions.
Part 1 is entitled ‘From the pion to QCD and pseudo-Goldstone bosons” and Part 2 “From the muon and neutrino to QFD and chiral
anomalies’.
Adapted from two lectures delivered at the University of Rochester in October, 1987. 相似文献
1000.
本指出:在均匀介质情况下H=B0/μ0的判据可简化为Bn=0;在介质图象下,“H仅与自由电流和介质的分布有关,而与磁化电流无关”的结论并不错。本还举例说明了静磁场中两种物理图象的应用。 相似文献