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161.
To date there has been only one test for local reality which used fermions. Lamehi-Rachti and Mittig measured correlated protons with a recoil polarimeter at Saclay. We discuss this experiment and survey the published criticism. We then propose an experiment involving a 500 MeV electron beam on a 3He target. The two protons in the 3He nucleus originally have their spins anti-aligned. The spins of the ejected protons can be measured with a recoil polarimeter and the correlation function obtained, which will be a good test of Local Reality and Bell's inequality.  相似文献   
162.
The Kirchhoff charge model is a viable method of generating inexpensive and electrostatically reasonable atomic charges for molecular mechanical force fields. The charging method uses a computationally fast algorithm based on the principle of electronegativity relaxation. Parameters of the method, orbital electronegativities and hardnesses, are fitted to reproduce reference, ab initio calculated dipole and quadrupole moments of a representative training set of neutral and charged organic molecules covering most medicinal chemistry relevant bonding situations. Transferability and accuracy of the derived parameters are confirmed on an external test set. Comparisons to other charge models are made. Implementation of the new Kirchhoff charges into a virtual screening engine is elucidated.  相似文献   
163.
通过仿真实验和传统实验比较,分析了仿真实验的优点,给出了虚拟仿真实验室的组成,结合我校使用的虚拟仿真实验教学系统,介绍了在物理实验教学过程中仿真实验的具体应用。  相似文献   
164.
以LabVIEW14.0为虚拟仪器软件开发平台,采用生产者/消费者设计模式的控制策略、技术数据管理流(TDMS)二进制文件储存策略和SQL数据库及事件结构相结合的实时更新策略,设计了集实时信息采集、储存、显示等功能于一体的应力波采集系统;3种控制策略相结合,解决了传统顺序结构设计模式下程序循环周期长、执行效率低的问题,而且解决了实时采集过程中数据的快速、大容量储存问题,实现了采集过程中采集参数的实时更新;实验结果表明该应力波采集系统具有响应速度快、执行效率高等优点。  相似文献   
165.
刘磊  付存文  张光山 《应用声学》2016,24(7):162-163
由于PXI设备的灵活性,在访问过程中需要用户参与到配置过程中。为了方便用户,并增强PXI设备访问的安全性和准确性,避免系统因用户配置问题导致的功能异常,提出了一种基于VISA的以PXI设备串号为基础的设备访问方法。通过将PXI设备的串号信息固化在PXI设备的配置寄存器中,根据设备串号信息自动获得设备资源描述符,进而对设备进行访问。实际应用表明,该方法能够完成对PXI设备的访问,避免了用户的配置过程,实现了PXI设备资源的自动配置,增强了设备访问的安全性和准确性,具有良好的实际应用价值。  相似文献   
166.
Given a perfect field of characteristic , a smooth proper -scheme , a crystal on relative to and a finite group acting on and , we show that, viewed as a virtual -module, the reduction modulo of the crystalline cohomology of is the de Rham cohomology of modulo . On the way we prove a base change theorem for the virtual -representations associated with -equivariant objects in the derived category of -modules.

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167.
By expanding the yielding function according to Taylor series and neglecting the high order terms, the elastoplastic constitutive equation is written in a linear complementary form. Based on this linear complementary form and the principle of virtual work, a finite element-complementary method is derived for elastoplastic problem. This method is available for materials which satisfy either associated or nonassociated flow rule. In addition, the existence and uniqueness of solution for the method are also discussed and some useful conclusions are given. The project is supported by the National Natural Science Foundation of China  相似文献   
168.
Methicillin-resistant Staphylococcus aureus (MRSA) is an important threat as it causes serious hospital and community acquired infections with deathly outcomes oftentimes, therefore, development of new treatments against this bacterium is a priority. Shikimate kinase, an enzyme in the shikimate pathway, is considered a good target for developing antimicrobial drugs; this is given because of its pathway, which is essential in bacteria whereas it is absent in mammals. In this work, a computer-assisted drug design strategy was used to report the first potentials inhibitors for Shikimate kinase from methicillin-resistant Staphylococcus aureus (SaSK), employing approximately 5 million compounds from ZINC15 database. Diverse filtering criteria, related to druglike characteristics and virtual docking screening in the shikimate binding site, were performed to select structurally diverse potential inhibitors from SaSK. Molecular dynamics simulations were performed to elucidate the dynamic behavior of each SaSK–ligand complex. The potential inhibitors formed important interactions with residues that are crucial for enzyme catalysis, such as Asp37, Arg61, Gly82, and Arg138. Therefore, the compounds reported provide valuable information and can be seen as the first step toward developing SaSK inhibitors in the search of new drugs against MRSA.  相似文献   
169.
The dynamics of an ensemble of two-level atoms injected into a single-mode cavity is studied in the exact atom-field interaction situation, in which the counter-rotating terms describing the so-called virtual photon processes neglected in the rotating-wave approximation, are considered. The cavity mode is driven by the injected classical field,and the atom is prepared in a coherent superposition of the two levels. We first derive the generalized Lorenz-Haken equation by using the technique of quantum Langevin equation, and then numerically study the dynamics of this equation.We find that the virtual photon processes have strong effects on the dynamics, which can cause the trajectory in phase space of strange attractor spiral around four focus points, and the trajectory is modulated by virtual photon processes.The chaos region in parameter space is now enlarged. It should be stressed that the strange attractor can exist in optical bistability, and whether the atomic coherences and classical field can inhibit chaos depends on the laser frequency.  相似文献   
170.
基于中美合作项目INDEPTH第3期在青藏高原布设的台站,使用虚拟震源测深法研究青藏高原中部的地壳厚度。结果显示,拉萨地体和羌塘地体的地壳结构存在巨大差异。拉萨地体的地壳厚度大约为57 km,与艾里均衡说预测的地壳厚度基本一致,说明拉萨地体的地壳结构比较简单。羌塘地体的地壳厚度为60~75 km,向北有增厚趋势,明显较艾里均衡说预测的地壳厚,说明羌塘地体地壳结构比较复杂,原因有可能是羌塘地体下存在高温流体和低速带,或者与印度板块岩石圈在班公湖-怒江缝合带以北向下俯冲有关。  相似文献   
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