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Elucidating ligand effects in rhodium(Ⅲ)-catalyzed arene-alkene coupling reactions

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Chinese Chemical Letters 2024年第5期35卷 130-134页

作者： Kongchuan Wu Dandan Lu jianbin lin Ting-Bin Wen Wei Hao Kai Tan Hui-Jun Zhang Department of Chemistry College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of Sciences(CAS)Beijing 100190China

Rhodium(Ⅲ)-catalyzed C-H couplings of arenes with alkenes are among the most powerful methods for C-C bond *** these transformations,subtle manipulation of ancillary ligands can lead to dramatic changes in reactivity and ***,detailed mechanistic studies concerning the ligand effects are *** this study,we investigated the origin of ligand-controlled product-selectivity in rhodium(Ⅲ)-catalyzed C-H couplings of arenes with alkenes,using a series of well-defined[CpXRhⅢ]complexes that feature electronically or sterically distinct Cp^(X)(Cp(η^(5)-C_(5)H_(5)),Cp^(CF3)(η^(5)-C_(5)Me_(4)CF_(3))and Cp^(∗)(η^(5)-C_(5)Me_(5)))ligands.A combination of experimental and theoretical investigations showed that(i)rhodium hydride species containing the electron rich Cp^(∗)ligand can undergo reinsertion of the alkene,thereby allowing rhodium-walking,(ii)rhodium hydride species involving the electron-deficient Cp or Cp^(CF3) ligands prefer reductive elimination rather than alkene *** findings offer valuable insights on future rational catalyst design for selective arene-alkene cross coupling reactions.

关键词： Organometallics Transition metal catalysis Arene-alkene coupling β-H elimination Rhodium hydride

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Hydrogen bonded foldamer-bridged biscoumarins:A UV-Vis absorption and fluorescent study of the solvent effect

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Chinese Science Bulletin 2010年第25期55卷 2870-2878页

作者： LU ZhengQuan ZHU YuanYuan lin jianbin JIANG XiKui LI ZhanTing Henan Institute of Chemistry Zhengzhou 450002 China State Key Laboratory of Bio-Organic and Natural Products Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

Three arylamide-bridged biscoumarin derivatives 1-3 have been designed and prepared. Compounds 1 and 2 are induced by the intramolecular N?H…O and N·H…F hydrogen bonding to possess a helical conformation,and 3 is induced to have an extended conformation. A comparison of their absorption and fluorescent spectra in a variety of solvents of a wide range of polarity with those of control compound 4 reveals that,for foldamers 1 and 2,the intramolecular hydrogen bonding and the helical conformations exist in most solvents,but do not exist or are very weak in DMF and DMSO.

关键词：紫外可见吸收光谱分子内氢键溶剂效应荧光光谱极性化合物螺旋构象 DMSO 衍生物

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海藻酶解物对大黄鱼生长和肠道菌群结构的影响

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动物营养学报 2024年第3期36卷 1819-1833页

作者：张露熊宇明董黎黎梁萍秦志清王磊江和基黄志坚殷光文林建斌王登峰福建农林大学动物科学学院(蜂学学院) 福州350002 福建省淡水水产研究所福州350002

为明确海藻酶解物饲喂大黄鱼的应用效果及对肠道菌群的影响,2022年11—12月在福建宁德海域使用添加0.5%复合海藻酶解物和0.5%海带酶解物的自配饲料饲养网箱养殖的大黄鱼8周,测定大黄鱼的存活率和平均增重,并采用NovaSeq PE250方案对肠... 详细信息

为明确海藻酶解物饲喂大黄鱼的应用效果及对肠道菌群的影响,2022年11—12月在福建宁德海域使用添加0.5%复合海藻酶解物和0.5%海带酶解物的自配饲料饲养网箱养殖的大黄鱼8周,测定大黄鱼的存活率和平均增重,并采用NovaSeq PE250方案对肠道内容物进行16S rDNA扩增子测序,分析肠道菌群组成和特定菌群的相对丰度。结果显示:0.5%的复合海藻酶解物或0.5%的海带酶解物均可显著提高大黄鱼的存活率和平均增重(P<0.05);肠道菌群分析显示0.5%复合海藻酶解物组大黄鱼肠道中扩增子序列变体(ASVs)达1353种,以厚壁菌门(Firmicutes)、变形菌门(Proteobacteria)、拟杆菌门(Bacteroidota)、梭杆菌门(Fusobacteriota)和放线菌门(Actinobacteriota)为主,而0.5%海带酶解物组大黄鱼肠道中ASVs仅242种,各样本中以厚壁菌门和脱硫杆菌门(Desulfobacterota)为主,变形菌门相对丰度较低,均与对照组(749个ASVs,各样本中菌门相对丰度无规律)有较大差异;基于KEGG的肠道菌群功能分析显示在淀粉和蔗糖代谢、谷胱甘肽代谢、磷酸转移酶系统、氰基氨基酸代谢、亨廷顿病和其他糖降解上3组存在显著差异(P<0.05);进一步分析发现,0.5%复合海藻酶解物增加了大黄鱼肠道菌群α多样性并提高了拟杆菌属及丁酸合成相关细菌的相对丰度,而0.5%海带酶解物则降低了大黄鱼肠道菌群α多样性,但可抑制肠道中假单胞菌属细菌的生长,且体外培养试验证实褐藻寡糖可极显著抑制变形假单胞菌生长(P<0.01)。综上可知,本试验制备的2种海藻酶解物可调节大黄鱼形成不同的肠道菌群结构,并均可促进大黄鱼的健康和生长,该结果可为大黄鱼海藻类饲料添加剂的开发和通过调整大黄鱼肠道菌群改善大黄鱼健康和生长的饲料添加剂研发提供数据参考。

关键词：大黄鱼海藻酶解物健康生长肠道菌群

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二溴代萘酰亚胺的高效合成

厦门大学学报（自然科学版） 2024年第1期63卷 43-48页

作者：王赟张桂兰林建斌厦门大学化学化工学院福建厦门361005

[目的]母核卤代的萘二酰亚胺(NDI)是制备各种NDI衍生物的重要前体,通过萘核C—X(X=Br,I)的定向转化,不仅可以有效调控分子能级,还有利于实现分子间的可控组装,是高效创制新型萘酰亚胺材料的有效手段,但传统合成卤代NDI的方法往往存在着... 详细信息

[目的]母核卤代的萘二酰亚胺(NDI)是制备各种NDI衍生物的重要前体,通过萘核C—X(X=Br,I)的定向转化,不仅可以有效调控分子能级,还有利于实现分子间的可控组装,是高效创制新型萘酰亚胺材料的有效手段,但传统合成卤代NDI的方法往往存在着合成效率低、选择性差等问题.为提高溴代NDI的合成效率,对其合成条件进行优化.[方法]通过提高溴化反应中溴源的回流程度和改善酰亚胺反应中二溴代萘四甲酸二酐(NDA-2Br)在反应溶剂中的溶解度,以2-乙基己基胺为研究对象,优化了酰亚胺反应的溶剂体系及时间,并将优化的溶剂体系应用于其他类型的胺.[结果]将溴化反应改用耐压瓶为反应容器后,在80℃下反应12 h合成的NDA-2Br产率达92%;优化后的酰亚胺反应溶剂体系为V(二甲亚砜)∶V(乙酸)=1∶2,在优化的反应条件下可高效合成二溴代NDI.[结论]与传统方法相比,该方法缩短了反应时间,避免了亲核取代副产物的生成,高效合成了二溴代NDI,具有操作简单、产物单一、可大量制备等优点.

关键词：萘二酰亚胺溴代胺化效率

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Perylene Diimide Double-Heterohelicenes as Chiral Organic Semiconductors for Broadband Circularly Polarized Light Detection

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Perylene Diimide Double-Heterohelicenes as Chiral Organic Se...

Discrete π-Stacks from Self-Assembled Perylenediimide Analogues

中国化学会第二届全国光功能材料青年学者研讨会

作者： jianbin lin Department of Chemistry College of Chemistry and Chemical Engineering MOE Key Laboratory of Spectrochemical Analysis and Instrumentation Xiamen University

By now, it remains a big challenge for the development of organic molecules for chiral organic semiconductors,because principles for design of chiral chromophores with highly-efficient and selective circularly polarized light（CPL）absorptions（e.g., designing highly distorted π-systems） have always been contradicted with the requirements for better charge transport abilities（e.g., extended planar π-system）.Based on our recent work on ortho-iodination of PDIs and further applications,1 we introduce a skeleton merging approach to address the dilemma during the development of chiral organic semiconductors. Regioselective ortho-π-extention of a perylene diimide（PDI） core with four fused heteroaromatics leads to the formation a special PDI double-[7]heterohelicene（Fig 1 a）, which both inherits a high dissymmetry factor from the helicene skeleton and maintains an outstanding charge transport ability from the extended PDI skeleton. Besides these two indispensable characteristics, ortho-π-extension of PDI skeleton brings about near-infrared（NIR） light absorption and ambipolar charge transport abilities, endowing the corresponding organic phototransistors with high photoresponsivity of 450 and120 m A W-1 in p-and n-type modes respectively, along with a high external quantum efficiency（89%） under NIR light irradiations. These multiple characteristics render high-performance broadband CPL detections up to NIR spectral region for the first time with chiral organic semiconductors（Fig 1 b, c, d, e）.

关键词： Double-Heterohelicenes Chiral Organic Semiconductors Circularly Polarized Light Detection

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Discrete π-Stacks from Self-Assembled Perylenediimide Analo...

Boosting the zinc storage performance of vanadium dioxide by integrated morphology engineering and carbon nanotube conductive networks

中国化学会·第十三届全国物理有机化学学术会议

作者： jianbin lin Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University

＜正＞The formation of well-defined finite-sized aggregates represents an attractive goal in supramolecular *** particular,construction of discreteπ-stacked dye assemblies remains a ***,we have developed an efficient...

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Nano Research 2024年第8期17卷 7136-7143页

作者： Lijie Ma Xiaolin Wang Xiang Chen jianbin Gao Yiwen Wang Yuehai Song Yaran Zhao Shizhe Gao lin Li Jianchao Sun School of Environment and Material Engineering Yantai UniversityYantai 264005China College of Textile Science and Engineering(International Institute of Silk) Zhejiang Sci-Tech UniversityHangzhou 310018China BNU-HKUST Laboratory of Green Innovation Advanced Institute of Natural SciencesBeijing Normal UniversityZhuhai 519087China Institute for Carbon Neutralization College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China

Vanadium dioxide(VO_(2)) with the advantages of high theoretical capacity and tunnel structure has attracted considerable promising candidates for aqueous zinc-ion ***,the intrinsic low electronic conductivity of VO_(2) results in an unsatisfactory electrochemical ***,a flower-like VO_(2)/carbon nanotubes(CNTs)composite was obtained by a facile hydrothermal *** unique flower-like morphology shortens the ion transport length and facilitates electrolyte ***,the CNT conductive networks is in favor of fast electron transfer.A highly reversible zinc storage mechanism was revealed by ex-situ X-ray diffraction and X-ray photoelectron *** a result,the VO_(2)/CNTs cathode exhibits a high reversible capacity(410 mAh·g^(−1)),superior rate performance(305 mAh·g^(−1)at 5 A·g^(−1)),and excellent cycling stability(a reversible capacity of 221 mAh·g^(−1)was maintained even after 2000 cycles).This work provides a guide for the design of high-performance cathode materials for aqueous zinc metal batteries.

关键词： VO_(2)/carbon nanotubes morphology engineering zinc metal batteries cathode materials conductive networks

Giant panda(Ailuropoda melanoleuca)neonates use broadband calls to communicate with their mothers

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Integrative Zoology 2024年第2期19卷 277-287页

作者： lin ZHAO jianbin CHENG Wen ZENG Bo YANG Guiquan ZHANG Desheng LI Hemin ZHANG Christina DBUESCHING Dingzhen LIU Ministry of Education Key Laboratory of Biodiversity Science and Ecological EngineeringCollege of Life SciencesBeijing Normal UniversityBeijingChina Key Laboratory of State Forestry and Grassland Administration on Conservation Biology of Rare Animals in The Giant Panda National Park China Conservation and Research Center for the Giant PandaDujiangyanSichuan611830China Department of Biology Irving K.Barber Faculty of ScienceUniversity of British ColumbiaOkanaganKelownaBritish ColumbiaCanada

Infant call structure should have evolved to elicit maximum maternal attention and *** of giant pandas produce three types of vocalizations reported to be vitally important in the context of mother–infant ***,how cubs,0–15 days old,communicate with their mothers to elicit maternal care remains *** analyzed 12 different call parameters of 3475 squawks,1355 squalls,and 491 croaks from 11 captive giant panda(Ailuropoda melanoleuca)neonates from age 0 to 15 *** playback experiments,we also tested whether mothers could detect *** results show that neonates use broadband calls with ultrasonic frequencies up to 65 kHz to convey information about their physiological needs and to attract maternal *** playback experiments,we tested if mothers reacted differently to broadband calls(BBC)than to artificially altered calls that included only frequencies20 kHz(USC).Playback confirmed that,although adult females responded significantly less often to USC,BBC than to or AUDC,they could detect USC,BBC and generally made appropriate behavioral responses,indicating a potential benefit for neonates to utilize ultrasonic and broadband *** findings provide a new insight into mother–infant communication in giant pandas and will be helpful for reducing the mortality of cubs,younger than 1 month old,in captivity.

关键词： acoustic communication broadband calls maternal care neonates ultrasonic frequencies

Effect of Laminarin on Growth and Immunity of Pearl Gentian Grouper

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Animal Husbandry and Feed Science 2017年第4期9卷 259-262页

作者： lin jianbin Liang Ping Zhu Qingguo Qiu Manli Fujian Provincial Institute of Freshwater Fisheries

[ Objective] The paper was to study the effects of laminarin on growth performance and immunity of pearl gentian groupers. [ Method] Four separate 30 m2 concrete pools were used as a closed circulating water aquaculture system for the experiment. Simultaneously, approximately 1 800 groupers were placed in each of the two pools for treatment or control. The initial weight of the individual fish was （275.55 ＋29.79）g. They were fed with either a control diet or one con- raining 0.6% laminarin in the pools for 66 d. [ Result] At the end of the feeding trial, the weight gain of the groupers in treatment group was increased by 29.03% （ P 〈 0.05 ）, the specific growth ratio was increased by 23.88% （ P 〈 0.05 ）, and the feed conversion rate was decreased by 15.20% （ P 〈 0.05 ） compared to control group, while there was no significant difference in muscle nutritional components between treatment group and control group （ P 〉 0.05 ）. For each kilogram weight gain of an individual fish, the cost of the treatment diet was 1.96 yuan less than that of control diet, i. e. , a reduction of 12.54%. On the other hand, the activities of alkaline phosphatase （AKP）, lysozyme （LZM） and total superoxide dismutase （T-SOD） of the groupers in treatment group were significantly higher than those in control group （P 〈 0.05 ）. [ Conclusion ] Addition of 0.6% laminarin in the regular feed would improve the growth performance and immunity of pearl gentian groupers in aquaculture.

关键词： Laminarin Pearl gentian grouper Growth performance Immunity