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1.
Xi-Le Wei 《中国物理 B》2022,31(12):128701-128701
This paper provides an adaptive closed-loop strategy for suppressing the pathological oscillations of the basal ganglia based on a variable universe fuzzy algorithm. The pathological basal ganglia oscillations in the theta (4-9 Hz) and beta (12-35 Hz) frequency bands have been demonstrated to be associated with the tremor and rigidity/bradykinesia symptoms in Parkinson's disease (PD). Although the clinical application of open-loop deep brain stimulation (DBS) is effective, the stimulation waveform with the fixed parameters cannot be self-adjusted as the disease progresses, and thus the stimulation effects go poor. To deal with this difficult problem, a variable universe fuzzy closed-loop strategy is proposed to modulate different PD states. We establish a cortico-basal ganglia-thalamocortical network model to simulate pathological oscillations and test the control effect. The results suggest that the proposed closed-loop control strategy can accommodate the variation of brain states and symptoms, which may become an alternative method to administrate the symptoms in PD.  相似文献   
2.
将锂原子三电子哈密顿量H分解为H0(类氦锂离子与氢原子哈密顿量之和)与H′(微扰项),用微扰法计算体系的能量.在计算E0时涉及类氦锂离子能量,计算类氦锂离子能量时我们像求氦原子能量一样使用变分法,同时对计算结果作了讨论。  相似文献   
3.
使用多体微扰理论(many-body perturbation theory,MBPT)计算了锰原子的3p^63d^54s^2→3p^53d^54s^2nd系列里德堡共振结构。在耦合方程方法中考虑了Auger图式,计算表明,Auger图式有效地抑制了3p→nd系列共振结构的发散。  相似文献   
4.
The intermolecular interaction potential for methane-argon complex is calculated by local density approximation (LDA) approaches. The calculated potential has a minimum when the intermolecular distance of methane-argon complex is 6.75 a.u.; the corresponding depth of the potential is 0.0163eV which has good agreement with experimental data. We also have made a nonlinear fitting of our results for the Lennard-Jones (12-6) potential function and obtain that V(R)=143794365.332/R^{12}-3032.093 / R^6 (R in a.u. and V(R) in eV).  相似文献   
5.
利用基于密度泛函理论框架下的局域密度近似方法对Ne-CH4分子间的相互作用势进行了计算. 发现: 当Ne原子和CH4分子之间的距离约为5.8 a.u.时, 计算的势能曲线存在最小值, 对应的势阱深度约为0.053 eV. 计算结果与实验值符合较好.  相似文献   
6.
小碳团簇结构的从头算分子动力学模拟   总被引:5,自引:0,他引:5  
引入第一原理密度泛函理论, 即赝势密度泛函在实空间的有限差分方法和朗之万分子动力学退火技术, 对碳团簇Cn(n=2-8)的基态结构进行了理论计算, 所得结果与其他作者的计算结果及实验数据吻合较好.  相似文献   
7.
再谈任意循环极限效率的p-V图证明   总被引:2,自引:1,他引:1  
白玉林 《大学物理》1997,16(8):48-48
在p-V图上用外切卡诺循环的方法证明任意循环的极限效率更为简单明了.  相似文献   
8.
Polarizabilities of small Sn (n = 2-8) clusters are calculated by using the higher-order finite-difference pseudopotential density functional method in real space. We find that the polarizabilities of the clusters are considered to be higher than the value estimated from the “hard sphere” model using the bulk static dielectric constant. The computed polarizabilities per atom tend to decrease with the increasing cluster size. The polarizabilities are closely related to the HOMO-LUMO gaps and the geometrical configurations.  相似文献   
9.
We employ a real-space pseudopotential method to determine the ground state structure of the carbon cluster C6 via simulated annealing and the corresponding optical absorption spectra from the adiabatic time-dependent density-functional theory (TDDFT) and the local density approximation (TDLDA).It is found that the ground state structure of the carbon cluster C6 belongs to a monocyclic D3h structure and the calculated spectra exhibit a variety of features that can be used for comparison against future experimental investigations.  相似文献   
10.
应用一维无粘流体反应动力学理论,选用13组元和40反应模型模拟了甲烷气体受高速飞片撞击的冲击反应流动,给出了飞片速度为9~12 km/s范围内共7个算例的数值结果.预测了在较高的飞片速度下,甲烷热分解反应的数值结果.Q  相似文献   
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