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101.
卢青林 《数学季刊》2009,24(2):168-172
In this paper, we consider the counting problem of matrix of set (Aij)k×n which satisfies k∪i=1 n∪j=1 Aij={a1,a2,…,am} and other conditions, and obtain some computational formulas which extend all the results in [1].  相似文献   
102.
True random number generators are essential components for communications to be confidentially secured. In this paper a new method is proposed to generate random sequences of numbers based on the difference of the arrival times of photons detected in a coincidence window between two single-photon counting modules.  相似文献   
103.
李雪明 《中国物理 B》2016,25(1):18710-018710
With recent breakthroughs in camera and image processing technologies single-particle electron cryo-microscopy(CryoEM) has suddenly gained the attention of structural biologists as a powerful tool able to solve the atomic structures of biological complexes and assemblies. Compared with x-ray crystallography, Cryo EM can be applied to partially flexible structures in solution and without the necessity of crystallization, which is especially important for large complexes and assemblies. This review briefly explains several key bottlenecks for atomic resolution Cryo EM, and describes the corresponding solutions for these bottlenecks based on the recent technical advancements. The review also aims to provide an overview about the technical differences between its applications in biology and those in material science.  相似文献   
104.
In this paper we discuss background counting rate minimization of a channel electron multiplier (CEM) using it in simple pulse counting mode. The minimization was investigated by a variable additional bias voltage applied to an aluminium source carrier set in front of a CEM entrance tube. For an optimal bias voltage of −20 V we found the background counting rate to be reduced to one twenty fifth of its value with no additional bias voltage applied.  相似文献   
105.
The Fukushima Dai-ichi NPP accident contaminated the soil of densely-populated regions in Fukushima Prefecture with radioactive cesium, which poses significant risks of internal and external exposure to the residents. If we apply the knowledge of post-Chernobyl accident studies, internal exposures in excess of a few mSv/y would be expected to be frequent in Fukushima.Extensive whole-body-counter surveys (n = 32,811) carried out at the Hirata Central Hospital between October, 2011 and November, 2012, however show that the internal exposure levels of residents are much lower than estimated. In particular, the first sampling-bias-free assessment of the internal exposure of children in the town of Miharu, Fukushima, shows that the 137Cs body burdens of all children (n = 1,383, ages 6–15, covering 95% of children enrolled in town-operated schools) were below the detection limit of 300 Bq/body in the fall of 2012. These results are not conclusive for the prefecture as a whole, but are consistent with results obtained from other municipalities in the prefecture, and with prefectural data.  相似文献   
106.
A Laplace Transform (LT) method is used to improve the results obtained in a quasi-elastic scattering (QELS) experiment. This is designed to determine the characteristic parameters of a bimodal solution of spherical and rod-like macromolecules. The theoretical study and the experimental simulation are carried out for low light levels and the results show that the LT technique provides a real alternative to the second order correlation function, g(2)(τ), in QELS measurements for these particularly difficult experimental conditions.  相似文献   
107.
在文 [1]中 , Barnsley等在关联矩阵不可约的条件下 ,得到了递归 IFS的分形维数公式 ,本文证 明 ,在去掉关联矩阵为不可约的限制条件之后 ,维数公式仍是成立的.  相似文献   
108.
本文推广了文献中的有限BCK-代数子代数个数估计定理,给出了任意BCK-代数的子代数个数下界的一个估计。对于n阶BCK-代数和n阶半直接既约交换BCK-代数,本文分别给出了其子代数个数下界的较具体的表达公式。另处我们还讨论了互不同构的n阶BCK-代数的个数的下界值的估计问题。  相似文献   
109.
张文  唐辉  顾静  耿萍  金利通 《化学学报》2005,63(14):1313-1317
制备了新型纳米二氧化锡电极, 将此电极用于水体中大肠杆菌的快速计数研究. 实验结果表明, 用该电极为工作电极, 采用计时电流法能简便、快速、灵敏地对水体中的大肠杆菌进行计数. 通过大肠杆菌脂质过氧化后丙二醛含量的检测, 对大肠杆菌在纳米二氧化锡电极上的电化学响应机理进行了初步的探讨.  相似文献   
110.
Non-linearity of the Yang-Mills fields caused by the commutator in the Lagrangian calls attention to symmetries helping to reveal important features of the system, while obviating the need of actual solutions. To this end, a charge fixing procedure is carried out by means of counting photon oscillations between test particles moving along trajectories that form Platonic solids shaped patterns. With the infinite-range electromagnetic interaction as its origin, the procedure defines a class of interactions allowed for particle physics. Besides the familiar electromagnetic, weak and strong interactions, the scheme suggests an unusual force that cannot be detected with conventional means though possibly contributes to gravitation.  相似文献   
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