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Drought-induced responses of organic osmolytes and proline metabolism during pre-flowering stage in leaves of peanut (Arachis hypogaea L.)

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Journal of Integrative Agriculture 2017年第10期16卷 2197-2205页

作者： ZHANG Ming WANG Li-feng ZHANG Kun liu feng-zhen WAN Yong-shan Key Laboratory of Crop Ecophysiology and Farming System Ministry of Agriculture/College of Agronomy Shandong Agricultural University Tai'an 271018 P.R. China

Peanut （Arachis hypogaea L.）, an improtant oil crop, usually encounters drought stress in the process of growth and development, especially at pre-flowering stage. In order to gain insight into the drought tolerance potentials based on osmolyte accumulation and metabolism of proline aspects of peanut, pot experiments were conducted with a split-plot design in Tai＇an, Shangdong Province, China in 2013 and 2014. Pre-flowering drought （PFD） stress and optinum irrigation （control, CK） were served as the main plots and the two peanut cultivars Shanhua 11 and Hua 17 served as sub-plots. Shanhua 11 was drought-tolerant cultivar and Hua 17 was drought-sensitive. The content of soluble sugars, soluble protein, free proline and other free amino acids, the activities of enzymes involved in proline metabolism, and malondialdehyde （MDA） content and ion leakage were all investigated in the two cultivars at pre-flowering stage. Results showed that PFD stress significantly increased the levels of soluble protein, free proline and free amino acid, and increased Al-pyrroline-5-car- boxylate synthetase （P-5-CS, EC 2.***.2.11） activity in the leaves of drought-tolerant and drought-sensitive cultivars. The activity of proline dehydrogenase （proDH）（EC 1.***.99.8） decreased under PFD stress in both cultivars. The leaves of the tolerant cultivar maintained higher increments of osmolyte levels, lower increments of MDA content and ion leakage, as well as a higher increased proportion of P-5-CS activity and higher inhibited proportion of proDH activity under water stress compared with the drought-sensitive cultivar. The study suggests that proline accumulation in peanut leaves under PFD can be explained by the higher enhanced activities of P-5-CS and higher inhibition of proDH. The results will provide useful information for genetic improvement of peanut under drought tolerance.

关键词： drought stress peanut (Arachis hypogaea L.) △1-pyrroline-5-carboxylate synthetase (P-5-CS) 5-ornithinetransaminase (OAT) proline dehydrogenase (proDH)

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Influence of ignition condition on the growth of silicon thin films using plasma enhanced chemical vapour deposition

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Chinese Physics B 2012年第1期21卷 314-319页

作者： Zhang Hai-Long liu feng-zhen Zhu Mei-Fang liu Jin-Long Graduate University of Chinese Academy of Sciences Beijing 100049China

The influences of the plasma ignition condition in plasma enhanced chemical vapour deposition （PECVD） on the interfaces and the microstructures of hydrogenated microcrystalline Si （μc-Si：H） thin films are investigated. The plasma ignition condition is modified by varying the ratio of Sill4 to H2 （RH）. For plasma ignited with a constant gas ratio, the time-resolved optical emission spectroscopy presents a low value of the emission intensity ratio of Ha to Sill＊（Iuα//SiH＊） at the initial stage, which leads to a thick amorphous incubation layer. For the ignition condition with a profiling RH, the higher IHα/ISiH＊ values are realized. By optimizing the RN modulation, a uniform crystallinity along the growth direction and a denser αc-Si：H film can be obtained. However, an excessively high IRα/ISIH＊ may damage the interface properties, which is indicated by capacitance-voltage （C-V） measurements. Well controlling the ignition condition is critically important for the applications of Si thin films.

关键词： plasma enhanced chemical vapour deposition microcrystalline silicon ignition condition

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Insertion of O—H Bond of Rh(Ⅱ)-methylene Carbene into Alcohols: A Stepwise Mechanism More Plausible than a Concerted Mechanism

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Chemical Research in Chinese Universities 2007年第2期23卷 221-225页

作者： liu zhen-feng WANG Yong YUE Xian-fang HAN Ke-li State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Sciences Dcdian 116023 P. R. China

The mechanisms of insertion of O-H bond of Rh（ Ⅱ ）-methylene carbene into methanol and ethanol were studied by using B3LYP functional both in gas phase and in CH2 C12. The formation of free alcoholic oxonium ylides is found to be impossible. Alcoholic oxonium ylide are formed as the intermediates before beth the stepwise and the concerted transition states of insertion of O-H bend of Rh（ Ⅱ ）-methylene carbene into methanol and ethanol. With re- gard to the mechanisms of insertion of O-H of Rh（ Ⅱ ） -methylene carbene into alcohols, analysis of the energy bartiers of the two mechanisms indicate that the stepwise mechanism is more plausible than the concerted mechanism.

关键词： Oxonium ylide 1,2-Hydrogen shift Density functional calculation Dirhodium( Ⅱ ) methylene carbene

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Studies on Lead Tungstate Crystal

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Chinese Physics Letters 1998年第1期15卷 46-47页

作者： liu feng-zhen HAN Jian-ru MAN Chang-feng CHEN Huan-chu HE Mao Department of Physics Shandong UniversityJi’nan 250100 Institute of Crystal Materials Shandong UniversityJi’nan 250100

The growth of lead tungstate(PWO)single crystals and their luminescence properties such as light yield,scintillation decay time,and transmittance were *** colourless PWO single crystal has been obtained by using the presyntheses ***,Nb,and Mg ions were doped in the crystals and the Ba-doped crystal has a relatively short decay *** crystal was found having a better transmission spectrum than that of unannealed one.

关键词： crystal decay annealed

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CHARACTERISTIC MAGNETIC RESONANCE ENHANCEMENT PATTERN IN CEREBRAL SCHISTOSOMIASIS

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Chinese Medical Sciences Journal 2006年第4期21卷 223-227页

作者： Han-qiu liu Xiao-yuan feng zhen-wei Yao Hua-ping Sun Department of Radiology Huashan Hospital Fudan University Shanghai 200040

Objective To describe the characteristic magnetic resonance imaging （MRI） appearance of cerebral schistosomiasis. Methods Twenty-five patients whose diagnosis of central nervous system （CNS） schistosomiasis had been pathologically （n = 8 ） and clinically （n = 17） confLrmed were randomly selected. MRI was performed on a Signal 1.5T MRI scanner before and after the intravenous administration of gadopentetate dimeghimine constrast medium. We reviewed the MRI studies obtained at the time of initial presentation, as well as follow-up studies obtained during and after medical treatment Results ImmunoLogicaL tests in L5 patients indicated schistosomiasis haematobium. Contrast-enhanced TL-weighted images in 22 cases showed central linear enhancement surrounded by multiple enhancing punctate nodules, which ap- peared “arborized”. Through operation and pathological examination, 8 cases had the granuloma formation of schistoso- mal eggs extensive surrounded by inflammation and venous congestion. And 17 cases were treated with praziquantel and corticosteroid therapy. And they were followed up for 2 months by taking MRI, which turned out to be complete resolution of the enhancing structure and edema. At follow-up, all the patients＇ initial symptoms also resolved. Conclnsion The specified MRI enhancement pattern of cerebral schistosomiasis is common in most cases of CNS schistosomiasis, so it should be taken account into the diagnosis of cerebral schistosomiasis.

关键词： cerebral schistosomiasis diagnosis magnetic resonance imaging

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Research on user-aware QoS based Web services composition

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The Journal of China Universities of Posts and Telecommunications 2009年第5期16卷 125-130页

作者： liu feng , LEI zhen-ming Key Laboratory of Information Processing and Intelligent Technology, Beijing University of Posts and Telecommunications, Beijing 100876, China Key Laboratory of Information Processing and Intelligent Technology Beijing University of Posts and Telecommunications Beijing 100876 China

To improve user experience of composite Web services, a user-aware quality of service （QoS） based Web services composition model is proposed. Under such model, a Web services selection method based on quantum genetic algorithm is proposed. This algorithm uses quantum bit encoding, dynamic step-length quantum gate angle adjustment, neighborhood service search and dynamic punishment strategy to expand search scope and speed up convergence. Simulation experiment shows that this algorithm is more efficient than other existing algorithms in Web services selection.

关键词： Web services composition user awareness quality of service quantum genetic algorithm

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User-perceived e-mail service QoS parameters and measurement

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The Journal of China Universities of Posts and Telecommunications 2010年第3期17卷 85-90页

作者： LI Yong-zhi , liu feng, LEI zhen-ming, CHEN Ling School of Information and Communication Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, China School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

A group of quality of service （QoS） parameters of electronic mail （e-mail） traffic are proposed from users＇ perspective. These parameters cover three fields： delay, throughput and usability. Concept and algorithm of each parameter are presented and its effect on user perceptions is described. In order to evaluate the effectiveness of these parameters, an active measurement system is implemented. Measured results show that the group of QoS parameters we proposed can be used to get a comprehensive view of user-perceived e-mail service QoS.

关键词： user perceptions e-mail service QoS active measurement

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基于GMRF的连续型储集层属性分布随机模拟

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石油勘探与开发 2005年第6期32卷 75-77,81页

作者：刘振峰郝天珧王峰中国石化石油勘探开发研究院中国科学院地质与地球物理研究所中国石油勘探开发研究院

连续型储集层属性分布预测是油气储集层研究的重要内容。定量化的方法有各种插值技术和基于地质统计学的一些随机模拟技术,不同方法各有其优缺点。对基于GMRF(Gaussian Markov Random Fields)模型的随机模拟方法的原理和算法进行了较为... 详细信息

连续型储集层属性分布预测是油气储集层研究的重要内容。定量化的方法有各种插值技术和基于地质统计学的一些随机模拟技术,不同方法各有其优缺点。对基于GMRF(Gaussian Markov Random Fields)模型的随机模拟方法的原理和算法进行了较为详细的介绍,实际模型的运算过程及结果表明,该方法较为简捷,同时连续型属性作为空间随机变量的两个特征———结构性和随机性也得到了很好的反映。

关键词： GMRF 连续型储集层属性随机模拟 MCMC

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植物光系统Ⅱ捕光过程的超分子结构基础

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生物化学与生物物理进展 2018年第9期45卷 935-946页

作者：李安节柳振峰中国科学院生物物理研究所中国科学院生物大分子科教融合卓越中心生物大分子国家重点实验室北京100101 中国科学院大学北京100049

光系统Ⅱ(photosystemⅡ,PSⅡ)是位于植物、藻类和蓝细菌等放氧光合生物类囊体膜上的重要超分子复合物,它可通过捕获光能用于激发反应中心的电荷分离并驱动电子传递过程,在常温常压下可将水分子裂解产生氧气和质子.植物光系统Ⅱ的外周... 详细信息

光系统Ⅱ(photosystemⅡ,PSⅡ)是位于植物、藻类和蓝细菌等放氧光合生物类囊体膜上的重要超分子复合物,它可通过捕获光能用于激发反应中心的电荷分离并驱动电子传递过程,在常温常压下可将水分子裂解产生氧气和质子.植物光系统Ⅱ的外周存在主要和次要捕光复合物Ⅱ(major and minor light-harvesting complexⅡ,LHCⅡ),它们负责吸收光能并向光系统Ⅱ传递激发能,并且还参与非光化学淬灭和状态转换相关的捕光调节过程.近年来,围绕光系统Ⅱ和LHCⅡ的结构生物学研究取得了一系列重要进展,本文总结了PSⅡ、LHCⅡ和二者共同组成的PSII-LHCII超级复合物的结构生物学研究历程以及最新进展,并对该领域的未来研究方向做出展望.

关键词：光系统Ⅱ 捕光复合物Ⅱ 结构生物学膜蛋白光合作用

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致密砂岩油气藏地震地质研究关键技术

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地球物理学进展 2014年第1期29卷 182-190页

作者：刘振峰中国石油化工股份有限公司石油勘探开发研究院北京100083

致密砂岩油气藏在当前油气勘探开中占有重要地位.地震地质综合研究是此类油气藏勘探开发工作的重要组成部分.多数致密砂岩油气藏地表条件复杂,导致地震资料品质较差.油气藏岩性致密、低孔、低渗的地质特征导致地球物理异常微弱.这两个... 详细信息

致密砂岩油气藏在当前油气勘探开中占有重要地位.地震地质综合研究是此类油气藏勘探开发工作的重要组成部分.多数致密砂岩油气藏地表条件复杂,导致地震资料品质较差.油气藏岩性致密、低孔、低渗的地质特征导致地球物理异常微弱.这两个不利条件给地震地质综合研究造成了较大的困难.结合致密砂岩油气藏地震地质研究工作实践,本文对地震资料特殊处理、储层和特殊地质体地震预测与描述的关键技术进展及应用效果进行了阐述.面对黄土塬、山地等复杂地表采集条件和致密砂岩储层等特殊地质体地震地质研究的需要,介绍了高精度静校正、叠前多域去噪、地表一致性振幅补偿、小波变换提高分辨率处理技术及在鄂尔多斯盆地一些探区的应用情况.围绕致密储层等特殊地质体的地震预测与描述需求,着重介绍了致密砂泥岩地层岩石物理分析、煤系等特殊地层的地震属性分析与优化、致密碎屑岩储层反演、叠前地震资料流体检测、致密储层裂缝发育带地震预测和储层综合建模等关键技术在部尔多斯及川西探区实际应用中面临的具体问题、改进对策和实施效果.

关键词：致密砂岩油气藏地震地质研究地震处理地震属性地震反演储层建模

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