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Microwave-Assisted Olefination Reaction of Alkylzinc with Aromatic Aldehyde Catalyzed by Nickel Complex

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有机化学 2003年第Z1期23卷 307-307页

作者： men Xiu-Qin wang Jin-Xian SHI Xiao-Ning wang Ke-Hu Institute of Chemistry Department of Chemistry Northwest Normal University Lanzhou 730070 Institute of Chemistry Department of Chemistry Northwest Normal University Lanzhou 730070 Institute of Chemistry Department of Chemistry Northwest Normal University Lanzhou 730070 Institute of Chemistry Department of Chemistry Northwest Normal University Lanzhou 730070

　　Carbon-carbon double bond-forming reactions have always been great importance in organic synthesis. Manymethods have been described for C =C bond formation. We[1] have reported the new method of C =C bond formatio... 详细信息

关键词： Nickel Complex aromatic aldehydes organic synthesis method of

Protein acetylation as a mechanism for Nostoc flagelliforme adaptation to drought stress

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Protein acetylation as a mechanism for Nostoc flagelliforme ...

中国植物学会第十六次全国会员代表大会暨85周年学术年会

作者： Lingxia wang Yang Liu Fengkun Yan Xiaoxu Li Miaomiao Ding men wang Jing Shi Tingting Xu Wenyu Liang School of Life Sciences Ningxia University Key Lab of Ministry of Education for Protection and Utilization of Special Biological Resources in Western China School of Agriculture Ningxia University

Nostoc flagelliforme,a terrestrial cyanobacterium,is well adapted to *** explore the adaptation mechanisms of *** in response to drought condition,a large-scale quantitative lysine acetylome was carried out using immunoaffinity enrichment of Lys-acetylated peptides and liquid chromatography linked to tandem mass spectrometry.A total of 1340 lysine acetylation（LysAc） sites,1340 Lysacetylated peptides and 653 Lys-acetylated proteins were *** conserved sequence motifs of the LysAc sites,including a new motif KxxK,were *** analyses revealed that the differentially acetylated proteins involved in response to drought condition were preferentially predicted to participate in glutathione metabolism and carbon metabolism and photosynthesis pathways based on KEGG pathway category enrichment *** found that GSH accumulation played important roles as stress protectant and reactive oxygen species scavenger,and soluble sugar accumulation improved the osmotic regulation ability in response to drought condition in *** energy metabolism-related proteins of *** were regulated by the LysAc modification under the environment of extreme drought to maintain lower *** with a large number of accumulation the energy metabolism of raw materials（glucose,pyruvic acid） are advantageous to quickly restore physiological activity under the condition of *** of physiological parameters and mRNA expression levels related to glutathione metabolism and carbon metabolism and photosynthesis were found to be significantly affected by drought *** together,reversible protein LysAc is likely to be a post-translational mechanism contributing to the ***’s adaptation to drought condition.

关键词： Nostoc flagelliforme drought condition protein acetylation

Olefination of Benzylzinc Halide with Aryl Acetone

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Olefination of Benzylzinc Halide with Aryl Acetone

中国化学会第四届有机化学学术会议

作者： wang, Ke-Hu LI, Hong-Xia men, Xiu-Qin wang, Jin-Xian (Institute of Chemistry, Department of Chemistry, Northwest Normal University, Lanzhou 730070)

＜正＞Alkene formation reactions are important tools in organic synthesis and a variety of methodologies have been devised for the conversion of carbonyl compounds into alkenes. Since Professor Georg Wittig discovered in 1953 the reaction of phosphonium ylides with carbonyl compounds to form alkenes, a variety of reagents have been developed for this transformation by a number of chemists. We have reported that organozinc halide reacts with aryl aldehydes in the presence of a silylating agent and using [NiCl2（PPh3）2] as the catalyst obtaining E-stilbenes. Herein, we report the reaction of benzylzinc halide with aryl acetones using Pd（PPh3）2Cl2 as the catalyst and obtained a series of E-stilbenes in good to excellent yields under mild conditions.

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Microwave-Assisted Olefination Reaction of Alkylzinc with Aromatic Aldehyde Catalyzed by Nickel Complex

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Microwave-Assisted Olefination Reaction of Alkylzinc with Ar...

第三届全国有机化学学术会议

作者： men, Xiu-Qin wang, Jin-Xian SHI, Xiao-Ning wang, Ke-Hu (Institute of Chemistry, Department of Chemistry , Northwest Normal University, Lanzhou 730070 )

＜正＞ Carbon-carbon double bond-forming reactions have always been great importance in organic synthesis. Many methods have been described for C=C bond formation. We have reported the new method of C=C bond formation of nickel catalyzed organozinc with aromatic aldehydes in the presence of Me3SiCl. In this procedure, various substituents on the phenyl ring, either electron withdrawing or electron donating, such as chloro, bromo, methoxyl, and benzyloxyl, could be tolerated and had little effect on the yield. The double bond is formed between the car-

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营商环境政策对企业投资的影响——基于湖北省企业微观调查数据

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青海民族研究 2021年第1期32卷 157-164页

作者：马德君汪鑫高敏王猛青海民族大学政治与公共管理学院青海西宁810007 华中师范大学湖北武汉430079

本文运用湖北省企业微观调查数据,应用横截面数据,利用二元决策模型等参数估计方法实证研究了营商环境政策对企业投资的影响。结果表明:企业在考虑投资时,对政策的长期稳定性和预期较为敏感,对当前状况并不敏感;在税收政策方面,税负水... 详细信息

本文运用湖北省企业微观调查数据,应用横截面数据,利用二元决策模型等参数估计方法实证研究了营商环境政策对企业投资的影响。结果表明:企业在考虑投资时,对政策的长期稳定性和预期较为敏感,对当前状况并不敏感;在税收政策方面,税负水平和税负的长期变动对企业投资决策具有显著的负向影响,但短期影响不显著;劳动用工政策方面,招工用工难度和员工平均工资对企业投资决策均无显著影响;融资政策方面,融资成本的变动对企业投资决策具有显著的反向影响,当期的融资难度和融资成本对企业投资决策没有显著影响;电力政策方面,电力保障率对企业投资决策具有显著的正向影响,但用电成本对企业投资决策无显著影响。故政策建议为:在政策稳定与预期方面,增强营商环境政策的长期稳定性,加强企业的预期管理;在融资政策方面,着力控制融资成本,提高融资便利度;在减税政策方面,在政府财政可承受范围内,加大减税力度和幅度;在降费政策方面,要着重降低公共服务费类、生产资料费类和资源使用费类等费用;对于大部分企业而言,尤其是知识密集型企业和中大型企业,不可降低职工的社保费、工资等劳动用工费;在电力政策方面,将电力的安全保障置于优先位置;多渠道提高企业效益,提高企业投资能力和内在动力。

关键词：营商环境企业投资企业微观调查数据

A Heavy Metal Analysis Device Based on Light-addressable Potentiometric Sensor

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稀有金属材料与工程 2006年第S3期 230-231页

作者： Hong men~1 Jianguo wang~1 Jing Gao~2 Ping wang~3 (1.College of Automation Engineering,Northeast Dianli University,Jilin 132012,China) (2.Department of Basic Courses,Jilin Medical and Pharmaceutical College,Jilin 132013,China) (3.Biosensor National Special Laboratory,Zhejiang University,Hangzhou 310027,China)

A full automatic device to detect heavy metal Hg,Fe,Cr elements based on thin-film sensitive materials prepared on surface of light-addressable potentiometric sensors （LAPS） by means of pulsed laser deposition PLD) technique is developed. High-purity chemical compound AgI:Ag2S:HgI synthesized were used as target of PLD,thin film sensitive to Hg~ （2+） ion was prepared on the surface of ***-solide-state chalcogenide glass ion-selective electrodes ISE) ,Fe-ISE and Cr-ISE,were also used as targets of PLD,and thin-film sensors on different LAPS sensitive to Fe~ （3+） and Cr~ （6+） ions were *** heavy metal analysis device with characteristics of collect sample in-site,real-time determination,communication and multifunction software were *** design of the device mainly includes control and measurement *** detected limits of Hg,Fe,Cr ions are 3.44×10~ （-7） mol/L,6.31×10~ （-6） mol/L and 2.09×10~ （-7） mol/L,respectively.

关键词： analysis chemistry sensor heavy metal LAPS PLD

Synchronization of Fitzhugh-Nagumo Neural Network in External Electrical Fields

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Synchronization of Fitzhugh-Nagumo Neural Network in Externa...

第二十九届中国控制会议

作者： men Cong,wang Jiang,DENG Bin,WEI Xi-Le,CHE Yan-Qiu School of Electrical Engineering and Automation,Tianjin University,Tianjin 300072,P.R.China

Synchronization is a crucial mechanism for information communication in neural ***,how external electrical fields modulate synchronization is remain an open *** this paper the stability of complete synchronization of coupled homogenous neural network in external electrical stimulation is investigated based on eigenvalue ***,the effects of network heterogeneity and field frequency on synchronization of heterogenous neural networks are studied in ***’s shown that coupling strength and topological structure play a crucial role in modulating the synchronous states in neural *** is sensitive to electrical field ***,heterogeneity plays an adverse role in achieving synchronous states.

关键词： Synchronization Topological structure Fitzhugh-Nagumo model Heterogeneity

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河北省玉米生长季干旱特征及成因分析

生态环境学报 2020年第4期29卷 763-770页

作者：代立芹李春强康西言王猛河北省气象科学研究所/河北省气象与生态环境重点实验室河北石家庄050021 唐山市气象局河北唐山063000

干旱是影响河北省玉米生长的重要农业气象灾害。利用玉米种植区1971-2018年气象资料和1981-2018年玉米(Zea mays)生长观测资料,以有效降水量代替实际降水量计算水分亏缺指数,对河北省玉米生长季干旱分布特征、变化趋势和变化成因进行了... 详细信息

干旱是影响河北省玉米生长的重要农业气象灾害。利用玉米种植区1971-2018年气象资料和1981-2018年玉米(Zea mays)生长观测资料,以有效降水量代替实际降水量计算水分亏缺指数,对河北省玉米生长季干旱分布特征、变化趋势和变化成因进行了分析。结果表明,(1)干旱概率和干旱强度分布特征基本一致,春玉米区由高到低依次为播种期>拔节-抽雄期>抽雄-乳熟期>出苗-拔节期>乳熟-成熟期,夏玉米区依次为播种期>抽雄-乳熟期>乳熟-成熟期>拔节-抽雄期>出苗-拔节期。(2)春玉米区4月下旬至5月上旬(播种期)和6月下旬至8月上旬(拔节-乳熟期)、夏玉米区6月上中旬(播种期)和8月上中旬(抽雄-乳熟期)受干旱影响较大,其中春玉米区以张家口和承德北部干旱最重,夏玉米区以石家庄东部、衡水西部和邢台东北部干旱最重。(3)春玉米区5月上中旬受需水量减少、降水量增加趋势影响,干旱强度和范围随年代显著下降,8月中下旬受需水量增加趋势影响,干旱强度和范围随年代显著上升;夏玉米区6月下旬受需水量减少趋势影响、9月下旬受需水量减少和降水量增加趋势影响,干旱强度均随年代显著下降。需水量减少与日照时数减少和风速减小密切相关,而需水量增加与气温上升、风速增大、空气湿度减少密切相关。

关键词：水分亏缺指数玉米干旱时空特征河北省

海南芒果蒂腐病可可球二孢抗药性及遗传多样性分析

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热带作物学报 2016年第7期37卷 1363-1369页

作者：王萌陈小莉赵磊卜小莉王莉巧曾宇松杨叶海南大学环境与植物保护学院海南海口570228 海南省农业科学院植物保护研究所海南省植物病虫害防控重点实验室海南海口571100

探索海南芒果蒂腐可可球二孢（Botryodiplodia theobromae）的抗药性、培养特性及遗传多样性的关系。以区分剂量法检测30个菌株对10种杀菌剂的敏感性,采用RAPD技术对菌株的遗传多样性进行分析。研究表明,芒果可可球二孢菌株对多菌灵、... 详细信息

探索海南芒果蒂腐可可球二孢（Botryodiplodia theobromae）的抗药性、培养特性及遗传多样性的关系。以区分剂量法检测30个菌株对10种杀菌剂的敏感性,采用RAPD技术对菌株的遗传多样性进行分析。研究表明,芒果可可球二孢菌株对多菌灵、甲基硫菌灵、醚菌酯、嘧菌酯、吡唑醚菌酯、苯醚甲环唑和咪鲜胺锰盐7种杀菌剂产生了抗药性,抗性菌株比率（MR和HR）分别为66.67%、70.00%、90.00%、76.67%、53.33%、20.00%和16.67%。供试菌株的培养特性存在明显差异。应用6个随机引物对共扩增出64条带,DNA多态率高达90.6%,遗传距离在0.58-0.86,芒果蒂腐病菌遗传分化较大。在遗传距离为0.65时,可分为两个群,群Ⅰ分成3个类群,共有26个菌株,群Ⅱ分成2个类群。聚合类型与菌株的抗药性表现一致。菌株的致死温度与聚合类型、抗药性有一定的关联。

关键词：芒果可可球二孢抗药性 RAPD分析培养特性