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71.
光学实验教学法的改进 总被引:5,自引:0,他引:5
对光学实验教学法做了一些改进:1)将单个光学实验划分为相对独立的单元,每个单元用不同的实验方法研究一个待测的物理量或观察分析一个物理现象;2)加强预习报告要求;3)以调整仪器为主的操作考核。 相似文献
72.
XiaoLingLIU XingCongWANG ShouRiSHENG XianHUANG 《中国化学快报》2004,15(9):1009-1010
The solid-phase synthesis of unsaturated β-dicarbonyl compounds has been reported. 相似文献
73.
Mark Bebbington Chin-Diew Lai Ričardas Zitikis 《Methodology and Computing in Applied Probability》2007,9(1):1-20
An important problem in reliability is to define and estimate the optimal burn-in time. For bathtub shaped failure-rate lifetime
distributions, the optimal burn-in time is frequently defined as the point where the corresponding mean residual life function
achieves its maximum. For this point, we construct an empirical estimator and develop the corresponding statistical inferential
theory. Theoretical results are accompanied with simulation studies and applications to real data. Furthermore, we develop
a statistical inferential theory for the difference between the minimum point of the corresponding failure rate function and
the aforementioned maximum point of the mean residual life function. The difference measures the length of the time interval
after the optimal burn-in time during which the failure rate function continues to decrease and thus the burn-in process can
be stopped.
相似文献
74.
75.
A general analytical theory is developed and numerical simulations are carried out of cylindrical plasma sources operating
at an industrial frequency of f=13.56 MHz ω=8.52×107 s−1). Purely inductive surface exciters of electromagnetic fields (exciting antennas) are considered; the exciters are positioned
either at the side surface of the cylinder or at one of its end surfaces. In the latter case, the plasma flows out of the
source through the opposite end of the cylinder. A study is made of both elongated systems in which the length L of the cylinder exceeds its diameter 2R and planar disk-shaped systems with L<2R. The electromagnetic fields excited by the antenna in the plasma of the source are determined, and the equivalent plasma
resistance, as well as the equivalent rf power deposited in the plasma, is calculated. 相似文献
76.
77.
We consider an inverse problem for the determination of a purely time-dependent source in a semilinear parabolic equation with a nonlocal boundary condition. An approximation scheme for the solution together with the well-posedness of the problem with the initial value u0 ∈ H1(Ω) is presented by means of the Rothe time-discretization method. Further approximation scheme via Rothe’s method is constructed for the problem when u0 ∈ L2(Ω) and the integral kernel in the nonlocal boundary condition is symmetric.
相似文献78.
Zhao‐Xun Lian Jia‐Min Zhang Ming‐Lu Xu Guang‐Ri Xu Tian‐Jun Lou 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(10):m445-m447
In the title compound, [Mn2(C8H4O7S)2(C10H8N2)2(H2O)2], pairs of hexacoordinated manganese(II) centres are bridged by 2‐sulfonatoterephthalate(2−) anions to form cyclic centrosymmetric dimers, which are linked into sheets by O—H...O hydrogen bonds. 相似文献
79.
80.