妙用极限思维法 巧解逻辑电路题

与逻辑电路相关的动态变化判断的题型,由于不是采用常规的串、并联电路图,而是逻辑电路和电平高低分析的电路图,所以一直以来都是难点,致使许多学生在考试的时候失分很严重.因此作为物理     

微小通道内空气流动特性实验研究

研究了空气在不同压比条件下,在内径分别为0.4 mm和0.5 mm的微圆直管内的流动特性.研究表明空气流过微圆管的阻力系数是常规管道的4至5倍,且存在层流状态提前过渡到湍流状态的提前转捩现象.微圆管管径越小,管内流动压力损失越大.     

对称电路等效电阻分析方法的探讨

两端电阻网络，其内部电阻仅是串、并联的结构，可以应用串、并联公式反复化简求出其等效电阻，若电阻网络中含有△或Y型结构，则需经过△与Y型电路的相互转换才能去掉△或Y型结构形成串、并联结构，然后再进行等效化简。若电路是对称结构的，由于对称电路中具有特定的等电位点，     

Expression and Emmprin Regulated Function of Aquaporinl in SMMC7221 Cells

<正>Herein lie the crosstalk and regulation between AQP1 and Emmprin in SMMC7221 cells by means of siRNA technology and deglycosylation method.Firstly,HAQP1,rather than hAQP3,was selectively upregulated in SMMC7221 cells by FBS,flollowed by the upregulated expression of Emmprin.Emmprin gene silencing caused a remarkable change in the expression of AQP1 gene,just like its downstream gene,MMP9,meanwhile the water permeability and cell migration were also descended prominently.Furthermore,when treated with tunicamycin, Emmprin was deglycosylated,which made the expression of AQP1 significantly declined,followed by remarkably decreased cell membrane water permeability and cell migration.Taken together,all the data indicates the expression level and the modification of Emmprin by glycosylation are the key factors in regulating the expression of AQP1.     

Effects of CRAC Channel on Spatiotemporal Ca2＋ Patterns in T Cells

A reaction-diffusion model is built to investigate the temporal and spatial patterns of cytoplasmic Ca2＋ dynamics under the effects of Ca2＋-release activated Ca2＋ （CRAC） channels in T cells. Simulation results show a strong dependence of the modulation mode of Ca2＋ oscillation and dynamic patterns of Ca2＋ wave on the influx rate through the CRAC channel （ksoc）. When ksoc is small, cytoplasmic Ca2＋ is modulated as a frequency-modulation （FM） signal, whereas it shows an amplitude modulation （AM） mode after ksoc passes through a critical value. The heterogeneity in spatial Ca2＋ distribution is mostly arising from the influx through CRAC channels in both FM and AM modes. During each Ca2＋ spike, a more sustained cytoplasmic Ca2＋ gradient is maintained in the AM mode rather than in the FM mode.     

与双模场依赖强度耦合下多光子通道中原子比特周期量子回声产生和调控

旋波近似条件下,运用全量子理论研究了与双模相干光场依赖强度耦合多光子通道中原子比特周期量子回声的产生和控制,采用数值计算的方法,讨论了双模相干光场平均光子数分布形式、分布范围及原子跃迁时吸收(或发射)的光子数k对原子比特态保真度演化的影响,获得了产生和控制原子比特周期量子回声的系统参量；根据纠缠理论,分析了原子比特态保...     

等离子体通道中的自生磁场

研究了超短脉冲强激光在等离子体通道中传播时产生的自生磁场．利用相对论动量方程和泊松方程及安培定律得出自生磁场的一个基本公式，在此基础上解析并数值研究了通道中产生的自生磁场的特性和结构，初步探讨了超短脉冲强激光在等离子体中传播时形成的排空效应对自生磁场的影响，并分析了产生自生磁场的机制 关键词：