Advancement of High Pulsed Electric Field for Inactivation of Microorganism

Inactivation of microorganisms can be realized by the accurately controlling the pulse electric field the strength and time for microorganism cell membrane. Use of high pulsed electric field for inactivation of microorganisms is one of the more promising nonthermal processing methods. Compare with pasteurization,it possesses the advantage of instant and even distribution throughout a conductive food system,short treatment time and very little heating of the medium in continuous processing. In addition, HPEF can decrease the loss of nutrition as little as possible. The author critically review the results of earlier experiment studies on HPEF,the mechanisms of inactivation by HPEF,and we suggest the future work that is required in this field.     

高压电场处理番茄果实的电磁学分析

以番茄果实为试材,在对真空和空气中的平行板电场进行电磁学分析基础上,研究了下极板摆放果实时平行板电场,中间插入金属板并摆放果实时平行板电场,中间插入电介质并摆放果实时平行板电场。结果表明,在极板间添加番茄后,由于增大了极板组成的电容器电容,造成极板电荷增大,空气层场强增大,番茄层场强相比于E_0有所减少;当电容器下极板摆满一层果实,并且在平板中间插入金属板,其上也摆满果实时,所组成的电容器等效电容C有所增大,极板上富集电荷Q有所增大,空气层场强相比于E_0有所增大,但E_f相比于E_0会随h及ε_h的不同产生变化;当电容器下极板摆满一层果实,并且在平板中间插入一层电介质,其上也摆满果实时,所组成的电容器等效电容C有所增大,极板上富集电荷Q有所增大,空气层场强相比于E_0有所增大,但E_f及E_h相比于E_0会随h及ε_h的不同产生变化。     

Development and Application of Steep Pulse Apparatus for Tumor Treatment

Under a certain electric field strength of steep pulse, plenty of micropores occur in the cell membrane. The number and diameter of micropore increase rapidly with the increase of electric field strength, the membrane breaks and the cell dies at last. This phenomenon is called as irreversible electrical breakdown (IREB). To research IREB of tumor cell, integrated with power electronics and conventional high voltage pulse generator, an energy-controllable steep pulse apparatus for tumor treatment is developed. The peak value, width, frequency and rise time of the output pulse can be adjusted independently, so the energy of the output pulse can be easily controlled. The apparatus is applied in cell experiment after a detailed analysis of its operating principle and debugging in laboratory. The experiment results show that the device works steadily and satisfies the demand of medical experiment.     

Analysis of spatial electric field with point-plateelectrodes configuration using finite element method

To investigate the spatial electric field with the point-plate electrodes configuration, variations of the electric field intensity are analyzed for absolute air dielectric and liquid dielectrics contained in air dielectric based on the finite element method of numeric computation. The results show that the electric field intensity of the spatial electric field is great non-uniform with the point-plate electrodes configuration for absolute air dielectric, and it can be increased rapidly at the nozzle point to achieve a maximum value. Single oil drop existed in air dielectric induces a biggish deformation of the gradient of the electric field intensity in its neighbor field. Many oil drops along with horizontal distribution have an obvious tensioning operation on the electric field, so the electric field intensity on the normal at the nozzle point has an evident augment for overlapping effects among the oil drops, and it can spread electric corona area of the total spatial electric field.     

Fractal Characteristic of Electric Polarization Feature of Coal

The dielectric response of charge carriers in disordered materials results from the process of fractal time and the conductance of the fractal structure. The medium metamorphism coal is one kind of structural disordered materials . So, electric polarization feature of coal has been further studied by using fractal geometry theory of time. The result shows that electric polarization property of coal in direct current electric field has fractal characteristic. The relation between b constant of polarization and fractal time dimension is:D t=kb, and the constant k may be relevant to metamorphism degree of coal.     

雷暴天气下建筑物周围电场畸变区域的研究分析

为了探究在雷暴发生时建筑物周围电场畸变区域的规律,利用Integrated Engineering Software电磁暂态仿真软件,模拟分析雷暴云及建筑物结构对周围电场畸变特征的影响。结果表明：当雷暴云过境时,群体建筑物遭受雷击的概率会减小,这主要是因为群体建筑物之间的屏蔽效应,改变了周围区域的电场畸变程度,降低了产生上行先导的概率和遭受雷击的概率。对于单体建筑而言,当雷暴云过境时,建筑物周围电场畸变区域呈半球形状,电场的畸变程度与建筑物的高度呈线性相关,高度越高,畸变区域越大,将导致前方流注扩展的区域变大,从而增加了下行先导发生的概率,这也是越高的物体易遭受雷击的原因。     

Simulation for the Power System of Fuel Cell/battery Electric Vehicle

The developmemt and research of taking fuel cell /battery as electric vehicle power is a new direction in abroad. A real-time simulation model for power driving system of a fuel cellbattery powered electric virtual vehicle is established. This electric vehicle powered primarily by 30 kw proton exchange membrane (PEM)fuel cells, with Lead-acid battery as assistant power, and with focus classis as virtual vehicle classis.The electric vehicle is simulated on the advisor platform, and the NEDC driving pattern simulation results show that the electric vehicle can satisfy the need of performance.     

不同电场处理条件对糜子种子萌发抗旱性的影响

采用平行板电场,研究不同电场处理条件对糜子种子萌发抗旱性的影响.结果表明,在干旱胁迫条件下,糜子种子发芽率下降,胚根长与胚芽长显著下降,胚根质量与胚芽质量显著上升.而经过电场处理后的糜子种子在干旱胁迫下发芽率整体呈上升趋势,胚根长与胚芽长下降趋势减缓,同时胚根质量与胚芽质量相对胁迫对照组有所增加.综合评价结果显示,电场处理糜子种子可以增强种子对干旱的耐受性.     

茄子种高压电场分选的粒重分布试验与分析

茄子种落入高压静电场中，受到场强作用，将沿电场方向产生位移，不同场强作用，茄子种分离区会不同，不同分离区，种子的粒重也不相同，分布也不相同，它们之间存在着紧密相关作用，本文定量揭示了这种关系。     

Responses of differentially expressed proteins and endogenous hormones in winter rapeseed (Brassica rapa L.) roots under water deficit stress

Winter rapeseed (Brassica rapa L.) can well-adapt to environmental conditions such as barrenness, water deficit and low temperature in arid and semi-arid planting regions and is the preferred rapeseed type. In this study, we analysed changes of root system morphology, antioxidant enzyme activity, endogenous hormone contents and differentially expressed proteins (DEPs) under control (CK), slight water deficit (SWD, 50–55% of maximum field water capacity), moderate water deficit (MWD, 40–45% of maximum field water capacity) and high water deficit (HWD, 30–35% of maximum field water capacity) conditions. Winter rapeseed experienced taproot elongation, decreased taproot diameter and increased lateral root number, under water deficit stress. The accumulation of reactive oxygen species (ROS) can cause membrane system peroxidation, and antioxidant enzyme activity increases to remove ROS. Changes in jasmonic acid (JA), salicylic acid (SA), cytokinin (CTK), auxin (IAA) and gibberellin (GA) levels promote the absorption of water and minerals by driving changes in the root system architecture to resist water deficit stress. A proteomic analysis has shown that DEPs are involved in energy metabolism, antioxidation response, osmotic regulation, hormone signal transduction, protein metabolism and the stress response, and these proteins are located in the peroxisome, chloroplast, mitochondrion, cell wall, vacuole, cytoplasm, extracellular space and cell membrane. In this study, multiple DEPs (malate dehydrogenase cytoplasmic 1 OS, 14-3-3-like protein GF14 Psi, GA 3-beta-dioxygenase, glutathione reductase and jasmonate-inducible protein) were involved in the root system architecture, revealing the complexity of the root response to water deficit. Significant/extremely significant synergistic relationships were observed between antioxidant enzyme activity and endogenous hormone contents. In conclusion, ROS, endogenous hormones and stress-related proteins work synergistically to control the root system architecture of winter rapeseed roots in response to water deficit stress.     

沙尘天气下大气电场与颗粒物关系研究

大气电场对各种气象要素的变化有着敏锐的反应,对一个地区大气电场特征的研究,有助于分析各种相关的天气过程,对该地区气候特征的研究也有重要意义。本文给出了太原地区3次沙尘天气下2个气象站内大气电场与大气颗粒物以及风速、湿度等气象要素相关性进行分析。结果表明,沙尘与晴天天气的大气电场有较大的差别,当沙尘到来后,大气电场值迅速下降,并且始终保持为较大的负值;沙尘天气下大气电场、PM10、PM2.5都发生剧烈的变化,PM1.0变化相对较小,其中沙尘天气下大气电场的绝对值、PM10、PM2.5分别比晴天天气下的值高3.94~5.74、2.07.94~5.89、1.28~5.91倍,沙尘天气下的PM1.0比晴天降低0.25~0.75倍）。不同粒径颗粒物的起电机理以及颗粒物来源不同导致颗粒物与大气电场的相关性不同,其中PM10、PM2.5呈较高的正相关,PM1.0呈负相关,且相关性较低。由于郊区站与城市站的下垫面不同,较大的风速将郊区站地表较大粗粒子吹起,使得郊区站沙尘大气电场在一些时段内会出现正值。     

Research Progress of the Cure Effect of Eelectrochemotherapy on Tumor

Electrochemotherapy is a new therapy on curing tumor, and it consists of two therapies, which are direct current electrochemotherapy and electric pulse aided antitumor medicine electrochemotherapy. Its widely application prospect is being taken on. Researchers home and overseas study deeply in the wide field of its cure mechanism, ways and means, animal tests and clinical application. Medical studies have shown that electrochemotherapy is an easily operated therapy with excellent curative effect and security. On the basis of these studies, a new therapy is put forward, that is, energy-controllable steep pulse therapy, electric pulse' killing effect on cell membrane is called as irreversible breakdown, and the first-stage study results of this new therapy are introduced.     

干旱胁迫对烤烟叶肉细胞超微结构的影响

为研究干旱胁迫时烤烟叶肉细胞超微结构变化规律,利用透射电子显微镜对其超微结构进行观察,揭示干旱胁迫对烤烟叶片细胞超微结构的影响,分析叶片细胞应对胁迫时各细胞器结构的变化。结果发现,干旱胁迫处理前,各细胞器结构完整。胁迫后,叶绿体类囊体首先膨胀变圆,随后结构崩溃,进而基粒片层松散、变形、断裂,直至完全降解;与正常衰老相比,淀粉粒虽增大但并未撑破叶绿体被膜游离到细胞质中;线粒体内膜内陷,破裂,但大部分外膜仍保持完整;细胞核出现明显的异染色质化,发生质壁分离,液泡所占细胞比例变小。     

不同类型冷浸田Fe2+对水稻生理酶活性的影响

铁毒致病的生理机理是植物体内积累过量的铁以及铁化合物诱发多种活性自由基,进攻膜脂,导致脂质的过氧化和膜的损伤。在过量Fe^2＋胁迫下,植株的超氧化物歧化酶（SOD）、过氧化物酶活性（POD）及丙二醛（MDA）含量的变化与抗铁毒密切相关。为了研究水稻对Fe^2＋毒害的响应机制,通过田间试验,对不同类型的冷浸田开展不同浓度Fe^2＋对水稻生理酶活性、生长发育及产量的影响。结果表明：不同类型冷浸田加入Fe^2＋后。水稻叶片和根系的POD、SOD活性MDA含量随Fe^2＋浓度的增加而提高,冷浸田（冷水田、烂泥田）的环境因子如低温提高了水稻的POD活性及MDA含量,降低了水稻的SOD活性,冷浸田（冷水田、烂泥田）水稻叶片和根系受Fe^2＋伤害的程度高于黄泥田;Fe^2＋对水稻生理活性的影响主要表现在分蘖期和抽穗期,尤其是水稻分蘖期的叶片和根系更容易受到Fe^2＋的伤害;适宜的Fe^2＋浓度有利于提高水稻产量。     

大气电场与大气污染物关系研究

为了研究大气电场与大气污染物关系,笔者利用太原地区2个气象站2012年6月—2015年5月的同步晴天大气电场、大气污染物、气象要素的观测资料,对太原地区晴天大气电场与大气污染物的相关性进行分析。结果表明：大气电场与大气颗粒物的相关性：PM₁₀>PM_2.5>PM_1.0,其中PM₁₀与大气电场的相关性比PM_2.5、PM_1.0显著大;大气电场与污染气体的相关性中NO_x较高,其次为O₃、CO,污染气体与大气基本带电粒子的相关性决定了它们与大气电场相关性的密切关系。通过对大气颗粒物的特征分析,给出了尖草坪大气电场高于桃园以及桃园大气电场在16:00左右出现1个小峰值的原因。     

Surface Charge Distribution and Tip Electric Field about Carbon Nanotubes

Carbon nanotubes(CNTs) have some special physic properties which may own important technical values. We studied the electric characteristics of metallic carbon nanotubes including potential distribution, surface charge distribution and tip electric field based on electromagnetic theory. Our results show that the relative values of tip charge densities of short CNTs are bigger and so are the absolute values for long CNTs. We also find the electric field at the tips of metallic nanotubes is much bigger than external electric field. This is helpful for exploring theoretical problems about CNTs' field emission.     

Nitrogen reduction stimulated by a three-dimensional electrochemical-biofilm reactor and its correlation with electric field

To realize automatic control, it is important to study the response of reactor to electric field. A three-dimensional biofilm eletrode reactor is developed and steadily operated to remove nitrogen. In the reactor, oxygen is produced on the anode and hydrogen is produced on the cathode of the three-dimensional electrode by electrolysis water. Microorganism in the reactor utilize oxygen and hydrogen adequately to remove nitrogen by nitrification-denitrification. To evaluate the correlation of electric field with the reactor, DO, pH and nitrogen removal efficiency are studied. Results show that when a electric field of 0.013 4 mA/cm 2 is applied to the system, the removal rate of NH +4-N, NO -3-N and TN is 90%, 70% and 70%, respectively. To assure the reactor run efficiently, the maximum of the intensity of electric field applied to the reactor is 0.0201 mA/cm 2. Within 0.0201 mA/cm 2, the system is in stable running status, while DO and pH is altered resulting from the intensity of electric field. With enhancing the intensity of electric field, the removal rate of NO -3 -N can be improved, although, the removal rate of NH +4-N is not elevated markedly. There is no accumulation of NO -2 -N within 0.0201 mA/cm 2.     

Model predictive control strategy of a medium hybrid electric vehicle

The intense coupled and nonlinear behaviors were observed on the tall long span tower line systems which were under the icing and wind loads in heavy icing areas. A set of stiffness equations of insulator, conductor and boundary conditions was deduced. Taking the ±800 kV UHV DC transmission line from Xiangjiaba to Shanghai as an example, the simplified numerical model of transmission tower, conductor, insulator and constraint was developed. The long span transmission tower line system models under seven loads conditions were analyzed by static nonlinear methods. It was found that the P Δ effect of tower components was small when the covered ice was uniformly distributed. The unbalanced wire loads on the tower would lead to twist effect when the covered ice was uneven distributed. The axial forces, moments at restraint nodes and the longest cantilever member were greatly affected by the P Δ effect, under which the unfavorable effect on the structure should be considered.     

Additive in Titania Electrorheological Fluid

This thesis studies the influences of additives on shear stress of electrorheologial fluid(ER fluid) in order to improve performance of ER fluid. ER fluid contains additives, and it is organic carboxylic acid(T1) or fatty acid and many entity mellow fat(T2,T3) .Then we test it. The result shows that all of the additives improve the performance of ER fluid. When the electric field is strengthened to 4 kV/mm under the condition that the content of additive is 3 percent, the shear stress of the ER fluid with different additive is improved in the rate of 12%,26%,33% respectively. The result also demonstrates that T1 contributes to a considerable increase in the stability of ER fluid. It is concluded that there will be a significant improvement in the property of ER fluid by dispersing appropriate type and a mount of additive to a certain ER fluid.     

小麦脂质转运蛋白基因TaLTP克隆及功能分析

脂质转运蛋白(lipid transfer protein,LTP)是广泛存在于植物中的一类小分子蛋白,因其能在植物细胞膜间运输脂类物质而得名,在植物角质层合成和适应多种环境胁迫中起重要作用。本研究利用同源克隆方法得到Ta LTP-s的c DNA全长序列510 bp,开放阅读框为339 bp,编码112个氨基酸。利用RIL群体将Ta LTP-s定位在染色体1A上,距离两侧标记WMC449和WMC93的遗传距离分别为2.1 c M和5.9 c M。通过原生质体亚细胞定位显示Ta LTP-s定位于细胞膜和细胞质中。小麦开花期Ta LTP-s在小花中表达量较高,尤其是在花药中的表达量远高于在根和叶中。在ABA、PEG、Na Cl及4℃低温胁迫诱导下,小麦Ta LTP-s均上调表达,可能与抗逆性调节相关。在高盐胁迫处理下,转基因拟南芥幼苗的细胞膜稳定性和存活率显著高于野生型。研究结果为利用小麦脂质转运蛋白基因改良作物抗逆性奠定了基础。