大棚草莓白粉病严重发生原因初步研究

试验表明草莓白粉病菌分生孢子不耐高温，但耐低温能力较强；最适宜分生孢子萌发条件为25℃高湿通气：大棚内的温湿度条件和变化特点十分适宜病菌分生孢子的形成和扩散；病菌不能在本地自然繁苗地上越夏，但保护遮阳条件下繁苗少数病菌可越夏并成为主要初侵染菌源和发病中心。     

陕西关中地区小麦白粉菌越夏问题的再探讨

入夏期在陕西杨凌室外小气候环境下设置小麦白粉菌越夏试验，人工夏播感白粉病小麦品种7期．结果表明，每播期麦苗均能以病菌无性世代分生孢子形态感染罹病，使白粉病菌顺利越夏．越夏期最热，旬平均气温为31℃、平均湿度为62．55％．从关中秦岭北麓和渭北旱塬麦区病菌越夏带调查分析表明，小麦白粉病菌可以分生孢子形态越夏存活；病菌越夏存活数量的多寡与当地越冬前菌源基础量的关系不大．     

改性硫磺颗粒的制备及其改性沥青路用性能

通过在硫磺中添加H2S抑制剂来制备改性硫磺颗粒(MSP),采用亚甲基蓝分光光度法测定改性硫磺颗粒与沥青混合加热过程中H2S释放量,并讨论H2S主抑制剂、辅助抑制剂的种类和用量对H,s释放量的影响,优化改性硫磺颗粒配方.结果表明:二硫化物抑制剂是最佳的主抑制剂,且随主抑制剂用量的增加,H2S抑制效果增强;少量的协同抑制剂极大地提高了改性硫磺颗粒对H,s的抑制能力.在最佳配方下,160 ℃时改性硫磺颗粒与沥青共混时H2s释放量为0.03μg/g,与纯硫磺相比H2S释放量降至0.68%;150℃时不同配方改性硫磺颗粒与沥青共混时H,S释放量为0.012～0.156μg/g,而纯硫磺与沥青共混时H2S释放量为0.956μg/g.添加适量改性硫磺颗粒,沥青混合料的动稳定度由l 073次/mm提高至2410次/mm,冻融劈裂强度比由75.3%提高至84.4%.改性硫磺颗粒具有显著降低H2s释放量、增强路面强度、改善抗水损害能力等优点.     

凤仙白粉病的病原菌鉴定

凤仙白粉病菌使凤仙花科植物叶片出现白色病斑.对河南商丘地区的凤仙白粉病菌进行了致病性分析、形态学及分子生物学鉴定.该病原菌分生孢子椭圆形或桶形,大小为22～28μm×16～21 μm.分生孢子梗直立,圆柱形,简单不分枝,包含1个足细胞,1～3个远基细胞,3～6个排列成链的桶形分生孢子,大小为112～180 μm×9～1...     

1.4%治腐星膏剂及单剂对苹果树腐烂病菌抑制作用研究

通过对1.4%治腐星膏剂及硫磺、硫酸铜单剂和对照为5%菌毒清水剂做抑制苹果腐烂病菌室内毒力测定。结果是：Ec50分别为：122.0956、287.7784、385.0142、18.5541μg/ml，1.4%治腐星膏剂共毒系数为205.4095，增效倍数为1.051。表明硫磺和硫酸铜复配制剂对苹果腐烂病菌抑制作用明显提高，可以复配使用。     

地表水水样氨氮的稳定性考察

该文以地表水水样氨氮的稳定性为研究对象进行了试验,对采集于聚乙烯塑料瓶内的氨氮地表水样,取一部分水样于2℃～5℃恒温冷藏保存,其余水样应立即加入硫酸,使pH值≤2进行现场固定,分别于2℃～5℃恒温冷藏保存,与15℃～25℃室温保存,每隔48h检测一次,连续检测一个月。检测结果统计表明,3种保存方法的测试结果基本一致,氨氮水样在一个月内的检测值基本恒定,水样表现稳定。     

Bt毒蛋白基因重组大肠杆菌的杀虫活性研究

本文对Bt毒蛋白基因(cry1Aa)重组大肠杆菌(ECE52)的发酵条件及杀虫活性进行了研究,结果表明该菌在37℃下培养或发酵8～12h较为合适.经超声波破碎的菌体对家蚕4龄幼虫有较强的毒性,用62.5×10-6g/mL的菌体稀释液处理过的桑叶饲喂4龄家蚕幼虫12h,96h内死亡率达100%.当浓度分别为125×10-6g/mL、250×10-6g/mL、500×10-6g/mL时,供试幼虫在72h,48h,24h内全部死亡.饲喂后24h,48h,72h的LC50值分别为0.101×10-3g/mL、0.045×10-3g/mL、0.028×10-3g/mL.     

河南省周口地区瓜类白粉病的分子鉴定与分析

对河南周口地区的瓜类白粉病进行了分子鉴定及分析.分别对黄瓜、甜瓜、葫芦、南瓜白粉病菌进行了扫描电子显微形态观察、核糖体DNA转录间隔区(ITS)克隆、测序及进化树分析.结果表明,周口地区的4种瓜类白粉病菌属于Sphaerotheca fuliginea,系统进化发现瓜类白粉病菌与豆类、美女樱、水母柱树白粉病菌种间差异小,同时发现该地区的瓜类白粉病菌与美洲、日本、澳大利亚、英国白粉病亲缘关系比较近,推测瓜类白粉病菌的进化与地域没有直接关系,而是与其自身的小种进化有关.     

浅议石河子乡灌溉方式

<正>石河子乡以种植经济、粮食作物为主,具有大陆性干旱气候特征,年平均气温6.3℃～6.8℃,一月份平均气温-16.2℃～-18.6℃,七月份平均气温25℃～26℃,日照2 318h～2732h,无霜期160d左右,年平均降水量140mm～200mm,年平均蒸发量15 00mm～2 400mm。属典型的干旱——干涸地区,没有灌溉就没有农业生产。     

金针菇葡枝霉病的研究

对金针菇葡枝霉病的病原物进行了分离培养、鉴定和生物学特性研究。结果认为:引起该病的病原菌为Cladobotryum varium Nees ex Steud。病原菌菌丝生长的适宜温度为10～30℃,最适温度为15～20℃。适宜的pH 值为4.5～8.0,最适pH 值为5.5。温度高、湿度大有利于病害的发生。室内药剂抑菌试验结果表明:质量浓度为0.01 g/L的百菌清和0.5 g/L～1.0 g/L的多菌灵对病菌的菌丝生长有较好的抑菌作用。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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