13μs,200ns和2ns脉冲电场对酵母菌杀灭效果分析

研究了脉冲宽度对高压脉冲下细胞膜和细胞器膜跨膜电压的影响及细胞膜能量的变化,以及13μs,200ns和2ns脉冲对酿酒酵母(CICC31180)杀灭作用时脉冲数的影响。结果表明,随着脉冲数增加,13μs,200ns和2ns脉冲对啤酒酵母的灭杀效果均增强。在13μs脉宽,14kV电压和50个脉冲数下,酵母达到最小存活率-4.3个对数;在200ns脉宽,40kV电压和500个脉冲数下,酵母达到存活率-2.6个对数;在2ns脉宽,200kV电压和500个脉冲数下,酵母达到存活率-2.8个对数。三种脉冲对酵母菌杀灭的存活率对数与脉冲数的关系表现不是线性的,脉冲数增加到一定程度,存活率下降变缓。在同等灭杀效果-2.0个对数下,2ns脉冲比13μs脉冲在同轴电极中损耗的能量更少。     

关于Lipschitz域上反射Brown运动的游程

本文具体刻画有界 Lipschitz 域上的反射 Brown 运动跨过某给定时刻 t 的离开 Martin 边界的游程．在此基础上,给出 Lipschitz 域上的反射 Brown 运动的边界过程的 L(?)vy 系统．     

关于Lipschitz域上反射Brown运动的游程

本文具体刻画有界Lipschitz域上的反射Brown运动跨过某给定时刻t的离开Martin边界的游程.在此基础上,给出Lipschitz域上的反射Brown运动的边界过程的Levy系统.     

Effect of helium-neon laser on fast excitatory postsynaptic potential of neurons in the isolated rat superior cervical ganglia

The aim of this study is to further measure the effect of 632.8-nm helium-neon laser on fast excitatory postsynaptic potential (f-EPSP) of postganglionic neurons in isolated rat superior cervical ganglia by means of intracellular recording techniques. The neurons with f-EPSP were irradiated by different power densities (1 - 5 mW/cm2) laser. Irradiated by the 2-mW/cm2 laser, the amplitude of the f-EPSP could augment (P < 0.05, paired t test) and even cause action potential at the end of the first 1 - 2 minutes, the f-EPSP could descend and last for 3 8 minutes. But the amplitude of the f-EPSP of neurons irradiated by the 5-mW/cm2 laser could depress for the irradiating periods. The results show that: 1) the variation of the amplitude of f-EPSP caused by laser is power density-dependent and time-dependent; 2) there exist the second-order phases in the interaction of the helium-neon laser with neurons. These findings may provide certain evidence in explanation of the mechanisms of clinical helium-neon lase     

贴片电阻表面缺陷自动识别方法

贴片电阻生产过程中的缺陷主要依靠人工在显微镜下检测,速度慢、长期成本高、误检率高.针对贴片电阻单元具有排列整齐、结构简单、图像灰度级少的特点,在贴片电阻图像二值化、边缘提取、直线检测基础上,以相邻电阻单元的相关系数作为电阻缺陷判别依据,提出基于子图投影匹配的快速缺陷检测方法.采用主分量分析法压缩图像数据量,提取缺陷特征,以基于支持向量机对贴片电阻缺陷进行分类并建立实验系统.缺陷检测及识别实验表明,缺陷检测正确率为92.5oo,算法的快速性和识别准确度满足系统快速高精的要求.     

广义半交换环的幂零结构

研究了广义半交换环的幂零结构,定义了一类新的环类,即幂零$\alpha$-半交换环.说明了$\alpha$-半交换环与半交换环, $\alpha$-半交换环和$\alpha$-刚性环等环密切相关,通过构造反例说明了幂零$\alpha$-半交换环未必是$\alpha$-半交换环.研究了幂零$\alpha$-半交换环的各种性质,推广和统一了与环的半交换性质有关的若干结论.     

毛细管电泳定量检测环境水样中无机阴离子

详细讨论了胶束浓度、间接吸收背景物质的浓度及有机添加剂组成等对部分卤素及其含氧酸根的毛细管电泳分离影响;在优化的条件下,3.5min内高效、快速地完成了Cl-、Br-、ClO3-、BrO3-四种无机阴离子的分离分析,分离的理论塔板数在1.6×106～2.8×105/m之间,检出限在11.2～23.3mg/L之间,迁移时间的相对标准偏差小于1%,峰面积的相对标准偏差在5.2%～2.2%之间;并将方法用于环境水样的分析。     

正则Dirichlet形式的正则子空间

正则Dirichlet形式的正则子空间问题,即存在性及其刻画等问题,是作者关注近20年的问题,该问题来自第二作者对于Markov过程的Killing变换的Dirichlet形式刻画问题的研究,这个问题是Dirichlet形式理论的一个基本问题,在最近10年中取得了一点进展.本文将主要叙述问题及其背景,并介绍围绕该问题得到的一些结果与遗留的问题.     

具有时滞的抑制细胞神经网络的周期解的存在性和全局指数稳定性

By using the Leray-Schauder fixed point theorem,differential inequality techniques and constructing suitable Lyapunov functional,several sufficient conditions are obtained for the existence and global exponential stability of periodic solutions for general shunting inhibitory cellular neural networks with delays.Some new results are obtained and some previously known results are improved.An example is employed to illustrate our feasible results.     

Effect of helium-neon laser on fast excitatory postsynaptic potential of neurons in the isolated rat superior cervical ganglia

The aim of this study is to further measure the effect of 632.8-nm helium-neon laser on fast excitatory postsynaptic potential(f-EPSP)of postganglionic neurons in isolated rat superior cervical ganglia by means of intracellular recording techniques.The neurons with f-EPSP were irradiated by different power densities(1 - 5 mW/cm2)laser.Irradiated by the 2-mW/cm2 laser,the amplitude of the f-EPSP could augment(P ＜ 0.05,paired t test)and even cause action potential at the end of the first 1 - 2 minutes,the f-EPSP could descend and last for 3 - 8 minutes.But the amplitude of the f-EPSP of neurons irradiated by the 5-mW/cm2 laser could depress for the irradiating periods.The results show that:1)the variation of the amplitude of f-EPSP caused by laser is power density-dependent and time-dependent; 2)there exist the second-order phases in the interaction of the helium-neon laser with neurons.These findings may provide certain evidence in explanation of the mechanisms of clinical helium-neon laser therapy.