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The simultaneous control over the alternating sequence and the inner- core position of the mesogenic segments in side-chain liquid crystal polymers

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JOURNAL OF MOLECULAR LIQUIDS 2022年 363卷

作者： zhang, Ruixue Ma, Hongwei Li, xuwen Wang, Bo Li, Chao Liao, Wen Li, Yang Han, Li Dalian Univ Technol Sch Chem Engn Dept Polymer Sci & Engn State Key Lab Fine ChemLiaoning Key Lab Polymer S Dalian 116024 Peoples R China

Hydrosilylated 1,1-diphenylethylene (DPE-SiH/2SiH) are herein quantitatively and alternatingly incorpo-rated during the living anionic copolymerization of isoprene with DPE-SiH/2SiH, which can efficiently control the Si-H densities and positions. The diversified mesogenic moieties containing azobenzene (Azo) or trifluoromethyl (F3C) groups, respectively, with the tuned inner-core position of the mesogenic segments are rationally designed and then fabricated into multiple alternatingly-arranged side-chain liq-uid crystal polymers (SCLCPs) along the alternating backbones. This study presents the novel SCLCPs with the simultaneous control over the sequence and the inner-core position of the mesogenic segment, pro-viding the promising route and study model to develop the mechanistic investigations. The temperature range of mesomorphic phase formation (delta T) and polarized optical morphologies are proved to be syner-gistically dependent on the diversified mesogenic moieties and the exactly controlled densities of the mesogenic segment. (C) 2022 Elsevier B.V. All rights reserved.

关键词： Living anionic copolymerization Side -chain liquid crystal polymers Alternating sequence Azobenzene (Azo) Trifluoromethyl (CF3 ) groups

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基于流-热-固耦合的水冷壁应力场数值模拟研究

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沈阳工程学院学报（自然科学版） 2023年第3期19卷 24-28,33页

作者：张进赵旭王许稳华能集团辽宁分公司华能丹东电厂辽宁东港118300 桂林电子科技大学机电工程学院广西桂林541004

锅炉水冷壁向火侧内烟气与水冷壁管内饱和水之间的传热,使水冷壁管间、水冷壁管与鳍片间、水冷壁向火侧和背火侧间产生较大的热应力。本文通过数值模拟获得垂直膜式水冷壁管屏在较高炉膛温度下的温度场和应力场分布,获悉了水冷壁管内压... 详细信息

锅炉水冷壁向火侧内烟气与水冷壁管内饱和水之间的传热,使水冷壁管间、水冷壁管与鳍片间、水冷壁向火侧和背火侧间产生较大的热应力。本文通过数值模拟获得垂直膜式水冷壁管屏在较高炉膛温度下的温度场和应力场分布,获悉了水冷壁管内压力及温度决定了水冷壁热应力的大小及分布,得知了水冷壁管与鳍片拉裂的原因是锅炉热负荷在短时间内的交替变化,其计算结果为水冷壁在发生热应力拉裂破坏条件下的改进及合理应对拉裂事故提供了方向。

关键词：水冷壁热应力数值模拟流固耦合水平烟道

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Recent advances in theoretical studies on transition-metal-catalyzed regioselective C-H functionalization of indoles

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JOURNAL OF MOLECULAR MODELING 2022年第9期28卷 267-267页

作者： Ma, Hongsheng Yu, Tongyan Chi, Longxiao Huang, Cong Li, xuwen zhang, Rui Deng, Chao Nanjing Agr Univ Coll Sci Jiangsu Key Lab Pesticide Sci Nanjing 210095 Peoples R China Nanjing Agr Univ Coll Sci Dept Chem Nanjing 210095 Peoples R China

Indole compounds are widely found in natural products and drug candidates. The transition-metal-catalyzed regioselective C-H bond functionalization of indoles as the most efficient method for the synthesis of various functionalized indoles has been extensively studied in the past two decades due to its advantages of step economy and atom economy. In general, the catalysts included the transition-metals (Pd, Rh, Ru, Cu, Co, Fe, Zn, and Ga) and these reactions were accomplished with a remarkably wide range of coupling reagents for construction of various C-C and C-X (X =N, O, S) bonds. However, the general and important rules of the regioselectivity are not clear to date. Therefore, a comprehensive analysis through previous reported theoretical studies on transition-metal-catalyzed regioselective C-H bond functionalization of indoles was crucial and significant. In this review, we found that when the C-H bond activation process was the rate-determining step, the regioselectivity ordinarily occurred at the C7 or C4 positions (on benzene ring), and otherwise, the regioselectivity often occurred at C2 position (on pyrrole ring). For indoline substrates, the C-H bond functionalization occurred at the benzene ring.

关键词： Indole C-H functionalization Mechanism Regioselectivity Transition-metals

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Functional characterization of TBL genes revealed the role of GhTBL7 and GhTBL58 in cotton fiber elongation

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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES 2023年第1期241卷 124571页

作者： Kabir, Nosheen Wang, xuwen Lu, Lili Qanmber, Ghulam Liu, Le Si, Aijun zhang, Lian Cao, Wei Yang, Zuoren Yu, Yu Liu, Zhao Zhengzhou Univ Sch Agr Sci State Key Lab Cotton Biol Zhengzhou Res Base Zhengzhou 450001 Henan Peoples R China Chinese Acad Agr Sci Inst Cotton Res State Key Lab Cotton Biol Anyang 455000 Henan Peoples R China Xinjiang Acad Agr & Reclamat Sci Cotton Res Inst Key Lab China Northwestern Inland Reg Minist Agr & Rural Affairs Shihezi 832003 Peoples R China Chinese Acad Agr Sci Western Agr Res Ctr Changji 831100 Peoples R China

TBL (Trichome Birefringence Like) gene family members are involved in trichome initiation and xylan acetylation in several plant species. In our research, we identified 102 TBLs from G. hirsutum. The phylogenetic tree classified TBL genes into five groups. Collinearity analysis of TBL genes indicated 136 paralogous gene pairs in G. hirsutum. Gene duplication indicated that WGD or segmental duplication contributed to the GhTBL gene family expansion. Promoter cis-elements of GhTBLs were related to growth and development, seed-specific regulation, light, and stress responses. GhTBL genes (GhTBL7, GhTBL15, GhTBL21, GhTBL25, GhTBL45, GhTBL54, GhTBL67, GhTBL72, and GhTBL77) exhibited upregulated response under exposure to cold, heat, NaCl, and PEG. GhTBL genes exhibited high expression during fiber development stages. Two GhTBL genes (GhTBL7 and GhTBL58) showed differential expression at 10 DPA fiber, as 10 DPA is a fast fiber elongation stage and fiber elongation is a very important stage of cotton fiber development. Subcellular localization of GhTBL7 and GhTBL58 revealed that these genes reside inside the cell membrane. Promoter GUS activity of GhTBL7 and GhTBL58 exhibited deep staining in roots. To further validate the role of these genes in cotton fiber elongation, we silenced these genes and observed a significant reduction in the fiber length at 10 DPA. In conclusion, the functional study of cell membrane-associated genes (GhTBL7 and GhTBL58) showed deep staining in root tissues and potential function during cotton fiber elongation at 10 DPA fiber.

关键词： G hirsutum TBL Fiber development Phylogenetic analysis Gene silencing

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碳中和愿景下林业碳汇经济价值评估及效率测算

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中南林业科技大学学报（社会科学版） 2024年第1期18卷 71-81页

作者：张亚连张启航梁旭文中南林业科技大学商学院湖南长沙410004

林业碳汇作为成本最低的碳吸收手段,是实现碳中和的重要途径。基于2008—2021年31个省级行政区的数据,估算了林业碳汇的经济价值,并将其纳入当前的林业经济核算体系中,构建了以林业碳汇价值为正外部性产出的DEA-Malmquist效率分析模型... 详细信息

林业碳汇作为成本最低的碳吸收手段,是实现碳中和的重要途径。基于2008—2021年31个省级行政区的数据,估算了林业碳汇的经济价值,并将其纳入当前的林业经济核算体系中,构建了以林业碳汇价值为正外部性产出的DEA-Malmquist效率分析模型。研究结果表明:总体上林业碳汇的经济价值较高,但区域间差异较大;2008—2018年,四大林区林业碳汇经济价值的排序为西南林区>东北林区>南方林区>北方林区,但在2021年南方林区反超东北林区,位居第二;林业碳汇效率呈现上升趋势,年增长速度达到31.9%,增速较高,在近三年来尤为突出;四大林区的林业碳汇效率的排序为南方林区>北方林区>西南林区>东北林区,技术进步效率为林业碳汇效率作出了巨大贡献,分时期来看,四大林区的Malmquist指数均呈现“U”型变动趋势。研究结果可为区域固碳增汇与可持续发展提供重要参考。

关键词：碳中和林业碳汇经济价值碳汇效率

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Investigation of the impact of threshold pressure gradient on gas production from hydrate deposits

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FUEL 2022年 319卷 123569-123569页

作者： Lu, Cheng Qin, xuwen Ma, Chao Yu, Lu Geng, Lantao Bian, Hang zhang, Keni Zhou, Yingfang China Geol Survey Guangzhou Marine Geol Survey Guangzhou 511458 Peoples R China Southern Marine Sci & Engn Guangdong Lab Guangzho Guangzhou 511458 Peoples R China China Geol Survey Ctr Oil & Nat Gas Resource Explorat Beijing 100083 Peoples R China China Univ Geosci Sch Energy Resources Beijing 100083 Peoples R China China Geol Survey Beijing 100083 Peoples R China Lawrence Berkeley Natl Lab Energy Geosci Div Berkeley CA USA Univ Aberdeen Sch Engn Aberdeen AB24 3UE Scotland

Many hydrate-bearing sediments are featured with unconsolidated argillaceous siltstones, which exist the non Newtonian flow and threshold pressure gradient due to the high content of clay. In this study, the threshold pressure gradient of hydrate reservoir in the South China Sea is experimentally clarified. The quantitative relationship between it and the reservoir parameters is established. The function of threshold pressure gradient has been added into TOUGH + HYDRATE simulator. Here, site SH2, a candidate for field testing comprising a clayey silt gas hydrate reservoir in the Shenhu area of the South China Sea, was chosen to investigate the effect of threshold pressure gradient on gas production behavior through numerical simulations. The simulation results show that threshold pressure gradient has a significant impact on gas extraction. When the experimental value was applied, the gas production was enhanced unexpectedly, where cumulative gas output doubled in 5 years. The active hydrate dissociating area (gas, water and hydrate coexist) has notably extended, accompanying with the expanding cool zone. Water blockage near well was relieved. However, with the increasing of threshold pressure gradient, propagation of pressure would be restrained seriously. The pressure and hydrate of far-field formations stay "frozen ". The bottom water invasion was weakened.

关键词： Natural gas hydrate Threshold pressure gradient Argillaceous siltstones Numerical simulation

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The inbound container space allocation in the automated container terminals

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EXPERT SYSTEMS WITH APPLICATIONS 2021年 179卷 115014-115014页

作者： Yu, Mingzhu Liang, Zhuobin Teng, Yi zhang, Zizhen Cong, xuwen Shenzhen Univ Coll Management Inst Big Data Intelligent Management & Decis Shenzhen 518060 Peoples R China Shenzhen Univ Coll Civil & Transportat Engn Shenzhen 518060 Peoples R China Guangdong Univ Educ Dept Comp Sci Guangzhou 510303 Peoples R China Sun Yat Sen Univ Sch Data & Comp Sci Guangzhou 510006 Peoples R China

In this paper, we study an inbound container space allocation problem in the automated container terminals using simulation-embedded optimization. We aim to allocate the container terminal yard space for a batch of arrived inbound containers so as to minimize the total AGV (Automated Guided Vehicle) waiting time in the space allocation process and the external truck waiting time in the future container retrieval process. We propose an integer programming model to characterize the problem and prove the NP-hardness of the problem. A simulation module is employed to estimate the container rehandle number happened in the retrieval process. A simulation-embedded genetic algorithm is developed to solve the problem. Numerical experiment results show that (1) The proposed algorithm can significantly affect the performance of the allocation decision and achieve a trade-off between fast computation and good solution quality. (2) The space allocation schemes of the inbound containers are affected by different factors, such as initial block layout, quantity of arriving containers, and containers' arriving information. (3) The automated container terminal operators who care about the external truck waiting time may consider the simulation-embedded approach when the block yard is congested.

关键词： Automated container terminal Inbound container Space allocation problem Simulation-embedded optimization

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黄色的蓝藻水华

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湖泊科学 2022年第4期34卷 1384-1391页

作者：宋挺张军毅李旭文朱家民胡俊江苏省无锡环境监测中心无锡214121 江苏省环境监测中心南京210008 上海市青浦区环境监测站上海201799

随着全球气候变化和水体富营养化,在过去几十年中蓝藻水华改变了全球的淡水生态系统.蓝藻因独有的藻蓝蛋白而大多呈现蓝绿色,因此其水华也常称为蓝绿藻水华.然而随着蓝藻水华关注度的不断提升,尤其是监测和研究的不断深入,经常在水体中... 详细信息

随着全球气候变化和水体富营养化,在过去几十年中蓝藻水华改变了全球的淡水生态系统.蓝藻因独有的藻蓝蛋白而大多呈现蓝绿色,因此其水华也常称为蓝绿藻水华.然而随着蓝藻水华关注度的不断提升,尤其是监测和研究的不断深入,经常在水体中发现蓝藻水华出现黄化的现象.例如,太湖出现的黄色蓝藻水华,冬春季以长孢藻属(Dolichospermum)水华为主,夏秋季以微囊藻属(Microcystis)水华为主.即使外观看起来是蓝绿色的蓝藻水华,但仔细观察形成蓝藻水华的群体颗粒,也有部分呈现黄色,反之亦然.实际上,鉴于色素组成的差异性,也许水体中就没有两个颜色完全一致的蓝藻群体颗粒.目前对于黄色的蓝藻水华及其形成机理,国内外鲜有报道和研究.光照和氮限制被认为是最有可能的原因.在关注蓝藻水华黄化的同时,更应该关注和研究这些颜色变化给蓝藻水华及水环境所带来的风险和挑战,尤其是对水生态管理工作的启发和意义.

关键词：蓝藻水华黄色叶绿素类胡萝卜素藻胆蛋白

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陆域大地电磁基础网规划与展望

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地质通报 2024年第4期43卷 489-502页

作者：秦绪文戴意蕴张耀阳肖都方慧裴发根何大双冯斌中国地质调查局北京100037 中国地质科学院地球物理地球化学勘查研究所河北廊坊065000 国家现代地质勘查技术研究中心河北廊坊065000 自然资源部地球物理电磁法探测技术重点实验室河北廊坊065000

阵列式大地电磁测深是区域地球物理调查的重点发展方向之一,对标国外先进水平和国家社会的基础性需求,中国阵列式大地电磁测深工作程度依然较低,缺乏整体规划,开展全国性观测计划亟需提上日程。系统总结了当前区域地球物理学的发展趋势... 详细信息

阵列式大地电磁测深是区域地球物理调查的重点发展方向之一,对标国外先进水平和国家社会的基础性需求,中国阵列式大地电磁测深工作程度依然较低,缺乏整体规划,开展全国性观测计划亟需提上日程。系统总结了当前区域地球物理学的发展趋势及国内外大地电磁网建设现状,提出了合作共建陆域多层级大地电磁基础网和大数据中心的顶层设计和规划布局,并对中国大地电磁基础网未来的重点发展方向进行了展望和思考。相关工作的顺利开展将为中国的区域地球物理调查拓展一项新属性参数,推动构建物性地球、结构地球和地球物理场四维模型,进而变革区域地球物理研究范式和工作模式,支撑中国深地探测走向世界前列。

关键词：区域地球物理大地电磁测深深地探测基础网建设观测监测体系数据库

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Photo-electrocatalytic degradation of cyclic volatile methyl siloxane by ZnO-coated aluminum anode: Optimal parameters, kinetics, and reaction pathways

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SCIENCE OF THE TOTAL ENVIRONMENT 2020年 733卷 139246-139246页

作者： Tang, Jiawei zhang, Chunhui Wang, Liangliang Hu, Yufeng Su, Peidong Wang, Wenqian He, xuwen China Univ Min & Technol Beijing Sch Chem & Environm Engn Beijing 100083 Peoples R China Environm Protect Res Inst Light Ind Beijing 100095 Peoples R China Shenzhen Univ Coll Chem & Environm Engn Shenzhen 518060 Peoples R China Chinese Acad Sci Res Ctr Ecoenvironm Sci Key Lab Drinking Water Sci & Technol Beijing 100085 Peoples R China

Cyclic volatile methylsiloxanes (cVMSs) are widely used in industrial processes and consumer products, which have been reported to be potentially toxic to human health due to their persistence and bioaccumulation. In this study, a novel photo-catalytic zinc oxide (ZnO)-coated aluminum (ZnO@Al) anode was prepared by a facile hydrothermal epitaxial process for the purpose of degrading cVMSs in practical wastewater. Morphological data and compositional analysis showed a compact coating layer that had the characteristic peaks of ZnO. To optimize the degradation process, central composite design combined with response surface methodology was applied to acquire the optimum parameters of cVMSs removal, and results indicated the cVMSs removal efficiency was approximately 63.3% at the conditions of current density = 17.3 mA/cm(2), initial pH of electrolyte = 7.8, plate distance = 18 mm, UV intensity = 90 W, and reaction time = 80 min. Furthermore, the photo-electrocatalytic degradation of cVMSs obeys the pseudo-first order kinetic reaction, and the anode exhibited high durability as the attenuation of cVMSs removal efficiency was <6% after four times reuse. It was also observed that with the application period of the anode was extended, the electroflocculation reaction gradually occurred. The FT-IR of the generated flocs and the total ion gas chromatograms mass spectrometer analysis unraveled the methyl groups in Si-CH3 could be easily attacked by hydroxyl radicals to form the intermediates of monohydroxy substituted products (m/z = 298, 372, and 446) and eventually short-chain carboxylic acids, alkyl radical and silicate. The effective removal of cVMSs by photo-electrocatalytic process using ZnO@Al anode provide significant implication in treatment of practical wastewater.

关键词： Photo-electrocatalysis ZnO Methyl siloxanes RSM

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