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Chinese Chemical Letters 2007年第4期18卷 377-379页

作者： shou Ri Sheng Ming Gang Hu Qin xin Xiao Ling Liu Xian Huang College of Chemistry and Chemical Engineering Jiangxi Normal University 330027 Nanchang China Department of Chemistry Zhefiang University Xixi Campus 310028 Hangzhou China

Reaction of polystyrene-supported lithium selenide with 3-acetoxy-2-methylene-alkanoates afforded the corresponding allyl selenide resins and subsequent cleavage from the polymer by treating with methyl iodide to furnish （Z）-allyl iodides in good yields and high purities. The polymeric selenium reagent can be regenerated and reused. So it is a environmentally benign reagent.

关键词： Solid phase organic synthesis Polystyrene-supported selenium bromide (Z)-Allyl iodide

Management of pesticide residues in China

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Journal of Integrative Agriculture 2015年第11期14卷 2319-2327页

作者： CHEN Zeng-long DONG Feng-shou XU Jun LIU xin-gang ZHENG Yong-quan Institute of Plant Protection Chinese Academy of Agricultural Sciences

This paper reviewed management of pesticide residues in China including laws and regulations, the supervision system, the standard system, and the quality and safety of agricultural products. The process of establishment and internationalization of standards for pesticide residues were also discussed. Results indicate that the progress of the management of pesticide residues has been steadily made in China. However, the following aspects which refer to updates to regulations, supervising efficiency, standard system, risk assessment, international cooperation and communication, should be further improved. China should draw lessons from international experience, and then establish its own management system, which focuses on pesticides controls by strictly following relevant laws and technical standards to ensure the quality and safety of agricultural products.

关键词： pesticide residue standard system supervision system development trend

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抗枯萎病宝岛蕉早花突变体的筛选与鉴定

南方农业学报 2024年第2期55卷 540-550页

作者：赵明龙芳武鹏莫天利黄相苏祖祥魏守兴邹瑜张欣林志城广西农业科学院生物技术研究所广西南宁530007 中国热带农业科学院热带作物品种资源研究所海南海口571101 中国热带农业科学院环境与植物保护研究所海南海口571101 广西植物组培苗有限公司广西南宁530007

【目的】筛选鉴定抗枯萎病香蕉品种宝岛蕉的早花突变体,为进一步利用突变体株系选育适应性更广的香蕉新品种提供参考依据。【方法】利用多代组织培养繁育结合田间种植对比试验,依据生育期短、抗病性强、株高矮、株产高和遗传稳定筛选目... 详细信息

【目的】筛选鉴定抗枯萎病香蕉品种宝岛蕉的早花突变体,为进一步利用突变体株系选育适应性更广的香蕉新品种提供参考依据。【方法】利用多代组织培养繁育结合田间种植对比试验,依据生育期短、抗病性强、株高矮、株产高和遗传稳定筛选目标,从宝岛蕉早花突变后代中筛选优良株系,以宝岛蕉为对照,按照香蕉种质资源描述规范对优良突变株系的形态特征和生物学特性等进行观察鉴定,测定分析植株球茎生长点部位碳、氮营养累积以及成花相关激素吲哚乙酸(IAA)、玉米素(ZR)、赤霉素(GA)和脱落酸(ABA)含量差异,通过ISSR分子标记检测突变体及其野生型之间的遗传变异和亲缘关系。以宝岛蕉和主栽品种(桂蕉6号及巴西蕉)为对照,利用伤根浸菌法进行苗期抗病性鉴定,并在广西和海南开展区域种植试验及田间抗病性鉴定。【结果】筛选获得优良突变株系0523(简称0523),其新植蕉平均株高280.0 cm,假茎基围80.5 cm、中围60.0 cm,较宝岛蕉分别减小14.0%、5.8%和11.8%,新抽总叶片数26~29片;果实营养品质和单株产量与宝岛蕉无显著差异(P>0.05,下同)。0523球茎生长点碳氮比较宝岛蕉显著提高19.0%(P<0.05,下同),GA和IAA含量显著降低24.8%和22.6%,ABA和ZR含量与宝岛蕉相比略有增加,差异不显著。抗病性苗期鉴定结果显示0523为中抗且偏强,抗性水平与宝岛蕉相比略有提高,桂蕉6号为高感。突变株系0523与宝岛蕉的多态性比率为8.8%,遗传相似系数为0.95,二者存在差异。0523在广西和海南各试验点第1、2造蕉平均发病率分别为4.5%和3.5%,较主栽品种降低87.8%和94.1%,各试验点发病率均显著低于主栽品种。0523第1、2造蕉的生育期较宝岛蕉显著缩短,与主栽品种无显著差异。【结论】突变株系0523具有抗枯萎病、早熟、矮化、适应性广等优良性状,可用来培育大面积推广的香蕉新品种,或作为亲本育种材料应用于香蕉育种研究。

关键词：早花突变体抗枯萎病选育香蕉

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碳酸盐岩储层闭合酸化模拟研究

科学技术与工程 2024年第7期24卷 2690-2698页

作者：罗攀登张士诚李永寿卢盼盼牟建业马新仿中国石油大学(北京)石油工程学院北京102249 中国石油化工股份有限公司西北油田分公司乌鲁木齐830011

酸压裂缝生产一段时间后导流能力会逐渐降低,常采用闭合酸化来提高已酸压裂缝的导流能力,闭合酸化模拟对闭合酸化设计意义重大,因此,针对该问题进行闭合酸化建模及数值模拟。首先,基于达西定理、物质平衡原理、酸岩反应动力学建立闭合... 详细信息

酸压裂缝生产一段时间后导流能力会逐渐降低,常采用闭合酸化来提高已酸压裂缝的导流能力,闭合酸化模拟对闭合酸化设计意义重大,因此,针对该问题进行闭合酸化建模及数值模拟。首先,基于达西定理、物质平衡原理、酸岩反应动力学建立闭合酸化数学模型;然后通过地质统计学中的序贯高斯模拟算法生成具有非均质性和空间关联性的初始裂缝宽度空间分布和裂缝表面基质渗透率分布;利用有限体积法对模型进行数值求解,用C++编制模拟计算程序;最后基于该模型进行广泛的数值模拟研究,分析酸液分布规律、裂缝表面溶蚀规律、酸液作用距离的影响因素及规律,并形成各种条件下的酸液作用距离图版。研究表明,初始裂缝宽度和裂缝表面粗糙度对裂缝表面溶蚀形态起主导作用,裂缝面溶蚀形态有均匀推进、指进溶蚀和沟槽溶蚀;裂缝宽度越小、粗糙度越大,裂缝表面溶蚀竞争越强烈,越容易形成沟槽,酸液作用距离越远;排量、注酸量正相关于活酸作用距离,酸液传质系数负相关于活酸作用距离;典型的施工排量、酸液用量、常用的酸液类型下,闭合酸化中酸液作用距离为20~60 m。此模型可以预测不同条件下酸液作用距离和酸蚀裂缝表面溶蚀形态,优化闭合酸化参数,为现场闭合酸化施工设计提供理论依据和指导。

关键词：闭合酸化数值模拟酸液作用距离裂缝面刻蚀形态序贯高斯模拟

Dynamically tunable microwave perfect absorber with flexible and lightweight properties based on magnetorheological material

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Progress in Natural Science:Materials International 2023年第6期33卷 843-853页

作者： xin Huang Yu Wang Dachao Chen Pingan Yang Mengjie shou Decheng Wu Jia Zhu Zhihao Zhou Rui Li Chongqing University of Posts and Telecommunications School of Automation

In this paper, a microwave perfect absorber based on magnetorheological material is proposed and *** absorber achieves broad-band, flexible, and lightweight properties through the fusion of a ***, full-wave numerical simulation is conducted, demonstrating that the proposed absorber achieves a peak absorption of 99.99 % at 13.95 GHz. Additionally, a broad bandwidth of 90 % absorption is observed from 10GHz to 18 GHz in full-wave simulation, and the experimental results ranges from 11.7 GHz to 16.1 ***, the proposed absorber could be fabricated using an easy and low-cost method where laser engraving method is adopted. Experimental measurements in the microwave anechoic chamber confirm that the experimental results align well with the simulation. Furthermore, the absorption mechanism of the proposed absorber is investigated through a detailed analysis of the electric field and magnetic field. This study presents an effective approach for achieving lightweight and flexible electromagnetic protection materials in the microwave range,which could facilitate the practical application of absorbers in the field of military anti-reconnaissance.

关键词： Metamaterial absorber Magnetorheological material Broadband Lightweight

好氧堆肥对生物炭理化性质及吸附Cd^(2+)稳定性的影响

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江苏农业学报 2024年第1期40卷 75-82页

作者：杨婷王守红马林杰张诚信寇祥明张家宏杨军袁秦徐荣江苏里下河地区农业科学研究所江苏扬州225007 江苏省生态农业工程技术研究中心江苏扬州225009

生物炭可作为畜禽粪污好氧堆肥中去除重金属的功能材料,但堆体内部复杂的环境变化会影响生物炭的理化性质,从而影响其对重金属吸附的稳定性。将普通秸秆生物炭(BC)和磁性秸秆生物炭(FBC)置于牛粪中进行30 d好氧堆肥试验,研究两种生物炭... 详细信息

生物炭可作为畜禽粪污好氧堆肥中去除重金属的功能材料,但堆体内部复杂的环境变化会影响生物炭的理化性质,从而影响其对重金属吸附的稳定性。将普通秸秆生物炭(BC)和磁性秸秆生物炭(FBC)置于牛粪中进行30 d好氧堆肥试验,研究两种生物炭基本理化性质及对Cd^(2+)吸附稳定性的影响。结果表明:堆肥处理使BC和FBC的比表面积分别增加20.56%和76.64%,总孔容分别下降2.36%和3.70%,平均孔径分别下降19.17%和46.54%,表面官能团发生变化,FBC的饱和磁化强度下降43.67%。堆肥后,饱和吸附Cd^(2+)的两种生物炭BC和FBC的TCLP提取态Cd(TCLP-Cd)占比和TCLP提取液pH(TCLP-pH)均呈下降趋势,其中TCLP-Cd占比分别从28.31%和22.85%显著下降至26.76%和13.85%(P<0.05),TCLP-pH分别从3.66和3.29显著下降至3.51和3.14。综上,堆肥老化改变了两种生物炭的理化性质,降低了其酸可提取态Cd的含量,提高了其吸附Cd 2+的稳定性,且FBC中Cd^(2+)的稳定性更强。

关键词：生物炭镉(Cd^(2+)) 堆肥吸附稳定性

Village Network Centrality in Rural Tourism Destination:A Case from Yesanpo Tourism Area,China

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Journal of Mountain Science 2015年第3期12卷 759-768页

作者： ZHANG Rui-ying XI Jian-chao WANG shou-kun WANG xin-ge GE Quan-sheng Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Tianjin Agricultural University

With the development of rural tourism, the cooperation of villages has become very *** the status and importance of each village can contribute to better understanding of the integrated rural tourism management and sustainable rural tourism development. The research focused on 46 villages of Yesanpo scenic spot in China(39°35'-40°north latitude, and 115°16'- 115°30' east longitude). Integrating the method of Geographical Information System(GIS) and social network analysis, the spatial centrality and interrelation of each village in Yesanpo tourism destination were evaluated. The results showed that xinggezhuang is the spatial core village of the whole 46 villages in Yesanpo tourism areas; xinggezhuang, Nanzhuang, Zhenchang, Daze, Liujiahe and Zishikou are sub-core villages of the six tourism spots. Magezhuang, Ximagezhuang, Eyu, Zishikou, Daze, Shangzhuang, Zhenchang and Xiazhuang should be support of the core villages, which provide subsidiary services and connects with other nodes. The results also indicated that the study of the village centrality will contribute to build an integrated hierarchy structure and to provide sufficient basis for further development of rural tourism destination.

关键词： Network analysis Centrality Ruraltourism Yesanpo

Total Synthesis of N-Methylsansalvamide A

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Chinese Chemical Letters 2006年第6期17卷 761-764页

作者： shou xin LIU Yan Lou GENG Xia TIAN Xiao Li ZHEN Jian Rong HAN College of chemical ＆ pharmaceutical Engineering Hebei University of Science ＆ Tecnnology Shijiazhuang 050018

Total synthesis of N-methylsansalvamide A was accomplished in solution phase by a convergent approach. An N-Boc-td-depsipepide 6 and a dipeptide ester 10 were prepared in the yield of 89% and 91%, respectively. Cycliz... 详细信息

关键词： Synthesis N-methylsansalvamide A solution phase cyclic depsipeptide.

Novel fabrication of copper oxides on AC and its enhanced catalytic performance on oxidative carbonylation of methanol

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Chinese Chemical Letters 2017年第1期28卷 70-74页

作者： Ke Shi shou-Ying Huang Zhong-Yao Zhang Sheng-Ping Wang xin-Bin Ma Key Laboratory for Green Chemical Technology School of Chemical Engineering and Technology Tianjin University Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072 China

Copper oxides（CuOx） nanoparticles dispersed on activated carbon（AC） were prepared by using vaporphase methanol as the reducing agent. The CuOx/AC as prepared exhibited an enhanced catalytic activity in oxidative carbonylation of methanol to dimethyl carbonate（DMC）. The catalytic performance was significantly influenced by reduction conditions including temperature and time. With the similar selectivity of DMC, the space time yield（STY） under optimal reduction conditions reached up to 408 mg g^-1h^-1, which is superior to conventional methods such as thermolysis and solvothermal reduction. Based on the characterization results of XRD, TEM and XPS, the good copper dispersion and high Cu^＋ content obtained by vapor-phase methanol reduction were mainly responsible for the high catalytic activity.

关键词： Dimethyl carbonate Oxidative carbonylation Copper oxides Vapor-phase methanol reduction Activated carbon

大熊猫栖息地裕河片区鸟类多样性及其季节动态

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兰州大学学报（自然科学版） 2024年第1期60卷 106-114页

作者：孔令望白永兴程志昌王守城马小强杜星南袁浩哲包新康兰州大学生命科学学院兰州730000 大熊猫国家公园裕河分局甘肃武都746000 文县自然资源局甘肃文县746400

于2020和2021年,分不同季节,通过样线法开展调查,辅以红外相机监测,对大熊猫栖息地裕河片区的鸟类多样性及其季节动态进行研究.共记录鸟类14目47科166种,其中国家Ⅱ级重点保护鸟类25种;世界自然保护联盟红色等级均为无危.鸟类区系以东洋... 详细信息

于2020和2021年,分不同季节,通过样线法开展调查,辅以红外相机监测,对大熊猫栖息地裕河片区的鸟类多样性及其季节动态进行研究.共记录鸟类14目47科166种,其中国家Ⅱ级重点保护鸟类25种;世界自然保护联盟红色等级均为无危.鸟类区系以东洋界(46.10%)和广布种(44.81%)为主,分布型最多的是东洋型(占27.72%).鸟类居留型组成以留鸟为主(占66.87%),夏候鸟也占有较大比例(占25.90%).鸟类群落的多样性指数以夏季最高(3.772),春季最低(3.166);物种数量以夏季种类最多,冬季鸟类的数量最多.各季节鸟类群落均以留鸟为主,季节变化不明显.区域的地理位置及其鸟类居留组成决定了裕河片区鸟类群落的季节动态特点.

关键词：鸟类多样性季节动态区系裕河保护区