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Preparation of polystyrene/silica nanocomposites by radical copolymerization of styrene with silica macromonomer

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science china {2. 2007年第3期50卷 385-391页

作者： ou baoli1,2.& li {2. college of chemistry and chemical Engineering, hunan university of science and technology, xiangtan 4112.1, china 2.State Key Laboratory of Powder Metallurgy, Central South university, Changsha 410083, china 1. college of chemistry and {2. Engineering Hunan University of Science and Technology Xiangtan 411201 China 2. State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China

A two-stage process has been developed to generate the silica-based macromonomer through surface-modification of silica with polymerizable vinyl groups. The silica surfaces were treated with excess 2.4-toluene diisocynate (TDI), after which the residual isocyanate groups were converted into polymerizable vinyl groups by reaction with hydroxypropylacrylate (HPA). Thus, polystyrene/silica nanocomposites were prepared by conventional radical copolymerization of styrene with silica macromonomer. The main effecting factors, such as ratios of styrene to the macromonomer, together with polymerization time on the copolymerization were studied in detail. FTIR, DSC and TGA were utilized to characterize the nanocomposites. Experimental results revealed that the silica nanoparticles act as cross-linking points in the polystytene/silica nanocomposites, and the glass transition temperatures of the nanocomposites are higher than that of the corresponding pure polystyrene. The glass transition temperatures of nanocomposites increased with the increasing of silica contents, which were further ascertained by DSC.

关键词： silica nanoparticles surface modification styrene radical copolymerization nanocomposites

Largeπ-extended donor-acceptor polymers for highly efficient in vivo near-infrared photoacoustic imaging and photothermal tumor therapy

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science china {2. 2021年第12期64卷 2180-2192页

作者： Jiangao li Hanlin {2. Jing li Xiaodi Yang Congwu Ge Dan Ding Xike Gao Key Laboratory of Synthetic and Self-Assembly chemistry for Organic Functional Molecules Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200032China State Key Laboratory of Medicinal chemical Biology Key Laboratory of Bioactive MaterialsMinistry of EducationCollege of Life SciencesNankai UniversityTianjin300071China china Innovation Research Institute of Traditional Chinese Medicine Shanghai University of Traditional Chinese MedicineShanghai201203China

Semiconducting polymers(SPs)with intensive near-infrared(NIR)absorption and high photothermal conversion efficiencies have been employed as a new generation of photothermal agents(PTAs)for“all-in-one”theranostic nanoplatforms with integrated photoacoustic imaging(PAI)and photothermal therapy(PTT)***,the lack of facile molecular design principles impedes the development of highly efficient NIR ***,a facile molecular design strategy based on largeπ-extended donor-acceptor(L-π-D-A)structure is reported for achieving SPs(SP1-SP3)with highly efficient in vitro and in vivo PAI and PTT *** adjusting the conjugation length and planarity of the donor units,both SP3 and corresponding nanoparticle(SPN)SPN3 exhibit stronger D-A strength,intensive NIR absorption,enhanced absorption coefficient,and higher photothermal conversion efficiency(up to 61.8%).The excellent photothermal conversion efficiencies make SPN1-SPN3 produce efficient inhibition of tumor growth with excellent biocompatibility and prominent PAI performance with a high contrast manner in living mice at a low systemic injection *** research highlights that the new L-π-D-A molecular design is an effective strategy to obtain highly efficient polymeric NIR PTAs for high desirable cancer phototheranostic nanoplatforms.

关键词： D-A polymers near-infrared photothermal agents photoacoustic imaging photothermal therapy

Racemic Bisindole Alkaloids: Structure, Bioactivity, and Computational Study

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Chinese Journal of chemistry 2021年第9期39卷 2588-2598页

作者： Tian-Yun Jin Ping-lin li Ci-li Wang Xu-li Tang Mei-Mei Cheng Yuan Zong lian-Zhong Luo Hui-Long ou Ke-Chun liu Guo-Qiang li Key Laboratory of Marine Drugs Chinese Ministry of EducationSchool of Medicine and Pharmacy DepartmentOcean University of ChinaQingdaoShandong 266003China Laboratory of Marine Drugs and Biological Products National Laboratory for Marine Science and TechnologyQingdaoShandong 266235China college of chemistry and {2. Engineering State-Province Joint Engineering Laboratory of Marine Bioproducts and TechnologyOcean University of ChinaQingdaoShandong 266003China Engineering Research Center of Marine Biopharmaceutical Resource Xiamen Medical CollegeXiamenFujian 361023China college of Ocean and Earth sciences Xiamen UniversityXiamenFujian 361006China Biology Institute Qilu University of Technology(Shandong Academy of Sciences)JinanShandong 250099China

The new racemic and dimeric in dole alkaloids with the characteristic cyclope nta[b]indole backb one,(+)-and(-)-sp on domi ne(la/lb),were isolated from a cultured sponge Tedania anhelans.A semi-synthesis was employed to obtain la/lb and the other four stereoisomers *** structures were determined by spectroscopic analysis,single-crystal X-ray,and quantum chemical *** stereoisomers differ in bioactivity according to their absolute con ***,(+)-sp on domi ne(la)displayed cytotoxicity against the K562.cell {2.ne and exhibited stronger Wnt and HIF1 dual signa{2.ng inhibitory activity at 5 pmol/L than the positive control,which offers an exciting starting point for further *** stereoisomers significantly promoted angiogenesis and showed moderate anti-inflammation in zebrafish.A quantum chemical calculation and deuteration experiment were app{2.ed to unveil the reacti on mechanism which guides the synthesis of the target compounds.

关键词： Tedania anhelans Alkaloids Cyclopenta[b]indole Biological activity Reaction mechanisms

FeS/SnS@rGO负极材料的制备及其电化学性能

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化工技术与开发 2024年第10期53卷 14-18,22页

作者：盘书恵卢秋影欧盈君黄蔚欣李华锋龚福忠广西大学化学化工学院广西南宁530004 广西新晶科技有限公司广西南宁530001

过渡金属硫化物具有良好的储锂性能,比容量高,有望成为锂离子电池的负极材料;缺点则是导电能力差,充放电过程中容易发生结构坍塌或体积膨胀,导致比容量下降较快,循环充放电性能差。针对此缺陷,本文将氯化铁、氯化锡、硫代乙酸铵、还原... 详细信息

过渡金属硫化物具有良好的储锂性能,比容量高,有望成为锂离子电池的负极材料;缺点则是导电能力差,充放电过程中容易发生结构坍塌或体积膨胀,导致比容量下降较快,循环充放电性能差。针对此缺陷,本文将氯化铁、氯化锡、硫代乙酸铵、还原氧化石墨烯(rGO)等组分在乙醇溶剂中充分混合后,采用溶剂热反应-高温热解法制备得到了氮掺杂、rGO包覆的复合材料FeS/SnS@N-rGO。在该材料中,FeS/SnS颗粒被片状rGO包裹形成三明治结构。作为锂离子电池的负极材料时,在0.1A·g^(-1)的电流密度下,首次充/放电比容量达到818.6/1430.0mAh·g^(-1),经过100次循环后,放电比容量为594.5mAh·g^(-1),在不同的倍率下充放电时,能保持较高的比容量和结构稳定性。

关键词：硫化铁硫化锡石墨烯溶剂热合成负极材料比容量

liposome-coated CaO_(2.nanoblockers for enhanced checkpoint blockade therapy by inhibiting PD-L1 de novo biosynthesis

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Nano Research 2023年第5期16卷 7227-7236页

作者： Ruijun Che Dandan Han Fei Wang Huifang liu Miao Fan Hongyu Yan Tingshan Xiao Zhaoshuo Wang Xiaohan Zhou Xueyi Wang Kaihan Zhang Caiwen ou Jinchao Zhang Zhenhua li college of chemistry&Environmental {2. Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of Ministry of EducationChemical Biology Key Laboratory of Hebei ProvinceHebei UniversityBaoding 071002China Affiliated Dongguan Hospital Southern Medical UniversityDongguan 523059China Guangdong Provincial Key Laboratory of Cardiac Function and Microcirculation Guangzhou 510515China college of Pharmaceutical science Key Laboratory of Pharmaceutical Quality Control of Hebei ProvinceHebei UniversityBaoding 071002China Department of chemistry the University of ManchesterManchester M139PLUK

The blocking of the immune checkpoint pathway with antibodies,especially targeting to programmed death-1/programmed death ligand-1(PD-1/PD-L1)pathway,was currently a widely used treatment strategy in clinical ***,the shortcomings of PD-L1 antibodies were constantly exposed with the deepening of its research and their therapeutic effect was limited by the translocation and redistribution of intracellular ***,we proposed to improve immune checkpoint blockade therapy by using liposomes-coated CaO_(2.(CaO_(2.@lipo)nanoparticles to inhibit the de novo biosynthesis of ***_(2.@lipo would produce oxygen and reduce hypoxia-inducible factor-1α(HIF-1α)level,which then downregulated the expression of *** in vitro and in vivo results have confirmed CaO_(2.@lipo promoted the degradation of HIF-1αand then downregulated the expression of PD-L1 in cancer cells for avoiding immune ***,to mimicking the clinical protocol of anti-PD-L1 antibodies+chemo-drugs,CaO_(2.@lipo was combined with doxorubicin(DOX)to investigate the tumor inhibition *** found CaO_(2.@lipo enhanced DOX-induced immunogenic cell death(ICD)effect,which then promoted the infiltration of T cells,strengthened the blocking effect,thus provided an effective means to overcome the traditional immune checkpoint blockade treatment.

关键词： immune checkpoint blockade therapy oxygen-producing hypoxia-inducible factor-1α(HIF-1α) programmed death ligand-1(PD-L1)redistribution immunogenic cell death

Clerodane-type Diterpene Glycosides from Dicranopteris pedata

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Natural Products and Bioprospecting 2021年第5期11卷 557-564页

作者： Bei‑Bei Gao Yu‑Fei ou Qin‑Feng Zhu Zhi‑Ping Zhou Zhen‑Tao Deng Meng {2. Qin‑Shi Zhao Key Laboratory of Medicinal chemistry for Natural Resource Ministry of EducationSchool of Chemical Science and TechnologyYunnan UniversityYunnan650091 KunmingPeople’s Republic of China State Key Laboratory of Phytochemistry and Plant Resources in West{2. and Yunnan Key Laboratory of Natural Medicinal chemistry Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China college of Pharmacy Guizhou Medical UniversityGuian New AreaGuizhou 550025China

Three new clerodane-type diterpene glycosides,(5R,6S,8R,9S,10R)-6-O-[β-d-glucopyranosyl-(1→4)-α-l-rhamnopyranosyl]cleroda-3,13(16),14-diene(1),(5R,6S,8R,9S,10R,13S)-6-O-[β-d-glucopyranosyl-(1→4)-α-l-rhamnopyranosyl]-2.ox-oneocleroda-3,13-dien-15-ol(2.,(5R,6S,8R,9S,10R)-6-O-[β-d-glucopyranosyl-(1→4)-α-l-rhamnopyranosyl]-(13E)-2.oxoneocleroda-3,14-dien-13-ol(3),together with two known compounds 4 and 5 were isolated from Dicranopteris *** structures of these compounds were elucidated by detailed spectroscopic analysis,and the absolute configuration of compound 2.was determined by ECD *** addition,compound 1 exhibited weak inhibitory activities against SMMC-772.,MCF-7 and SW480.

关键词： Dicranopteris pedata Clerodane-type diterpene glycosides ECD

High-density/efficient surface active sites on modified separators to boost li-S batteries via atomic Co^(3+)-Se termination

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Nano Research 2022年第8期15卷 7199-7208页

作者： Shujie liu Xiaofei liu Manfang Chen Dong Wang Xin Ge Wei Zhang Xiyang Wang Chunhui Wang Tingting Qin Haozhe Qin liang Qiao Dan Zhang Xing ou Weitao Zheng Key Laboratory of Automobile Materials of MOE School of Materials Science and Engineeringand Electron Microscopy Centerand International Center of Future ScienceJilin UniversityChangchun 130013China Key Laboratory of Materials Design and Quantum Simulation College of ScienceChangchun UniversityChangchun 130022China National Base for International science&technology Cooperation School of ChemistryXiangtan UniversityXiangtan 411105China State Key Laboratory of Chem/Bio-Sensing and Chemometrics Advanced Catalytic Engineering Research Center of the Ministry of EducationCollege of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China Department of Mechanical and Mechatronics Engineering University of WaterlooWaterlooN2L 3G1Canada School of Metallurgy and Environment Central South UniversityChangsha 410083China

Various and critical electrocatalytic processes are involved during the redox reactions in the li-S batteries,which extremely depend on the surface structure and {2. ***,single-atom concept unlocks a route to maximize the use of surface-active atoms,however,further increasing the density of active site is still strictly limited by the inherent structure that single-atoms are only highly-dispersed on ***,we provide a viewpoint that an elaborate facet design with singlecrystalline structure engineering can harvest high-density surface active sites,which can significantly boost the electrocatalyst performance for excellent li-S ***,the single-crystal CoSe_(2.(scCS)exhibits three-types of terminated(011)facet,efficiently obtaining the surface with a high-rich Co^(3+)–Se bond termination,in contrast with lots of surface grain boundaries and dangling bonds in polycrystalline CoSe_(2..Surprisingly,the surface active sites concentration can reach more than 69%.As anticipated,it can provide high-density and high-efficient active sites,enormously suppressing the shuttle effect and improving the reaction kinetics via accelerating the conversion and deposition of polysulfides and *** surface lattice strategy with element terminated mode is a promising approach for designing electrocatalyst effect-based energy system,not merely for li-S batteries.

关键词： high-density surface active sites Co^(3+)-Se covalent bond atomic element terminated li-S batteries single-crystalline strategy

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高活性氮化碳纳米片的制备策略

物理化学学报 2021年第8期37卷 14-24页

作者：李开宁张梦曦欧小雨李睿娜李覃范佳杰吕康乐中南民族大学资源与环境学院催化转化与能源材料化学教育部重点实验室武汉430074 郑州大学材料科学与工程学院郑州450001

二维聚合物材料氮化碳纳米片因具有独特的电学特性、化学稳定性,在环境治理、能源转换领域有广阔的应用前景。开发绿色友好、经济高效的g-C_(3)N_(4)纳米片剥离策略和合成方法,是催化、能源、材料领域的热点问题。本文重点介绍了关于二... 详细信息

二维聚合物材料氮化碳纳米片因具有独特的电学特性、化学稳定性,在环境治理、能源转换领域有广阔的应用前景。开发绿色友好、经济高效的g-C_(3)N_(4)纳米片剥离策略和合成方法,是催化、能源、材料领域的热点问题。本文重点介绍了关于二维g-C_(3)N_(4)纳米片的剥离方法与制备策略的研究进展,同时对现有方法进行对比和分析,主要包括热氧化刻蚀、超声辅助剥离、化学法、机械法以及模板法等。文章的最后对g-C_(3)N_(4)纳米片的剥离制备所面临的问题和挑战,进行了讨论,并展望其未来发展方向。

关键词：氮化碳纳米片剥离光催化半导体

氧化反应调控的金纳米簇“关—开”型荧光探针检测过氧化氢和葡萄糖

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光谱学与光谱分析 2022年第12期42卷 3757-3761页

作者：欧丽娟李京张超群罗建新韦吉王海波张春燕湖南工学院材料科学与工程学院湖南衡阳421002 信阳师范学院化学化工学院河南信阳464000

基于过氧化氢(H_(2.O_(2.)氧化单巯基(—S)为双巯基(S—S),抑制金纳米簇(AuNCs)荧光猝灭,建立了一种灵敏的荧光传感方法用于过氧化氢和葡萄糖(Glu)的检测。DNA为模板合成的金纳米簇作为荧光探针,荧光强度高、稳定且合成简单快速。加入... 详细信息

基于过氧化氢(H_(2.O_(2.)氧化单巯基(—S)为双巯基(S—S),抑制金纳米簇(AuNCs)荧光猝灭,建立了一种灵敏的荧光传感方法用于过氧化氢和葡萄糖(Glu)的检测。DNA为模板合成的金纳米簇作为荧光探针,荧光强度高、稳定且合成简单快速。加入半胱氨酸(Cys),半胱氨酸上的单巯基可以与金纳米簇发生化学键合反应形成稳定的Au—S键,破坏金纳米簇的结构,导致金纳米簇荧光强度猝灭。但当体系中存在过氧化氢时,将单巯基半胱氨酸氧化成双巯基的胱氨酸。双巯基的胱氨酸不能与金纳米簇发生键合作用,金纳米簇在471 nm处发射出强烈的荧光信号。葡萄糖可以在葡萄糖氧化酶(Gox)的作用下产生过氧化氢,利用该方法进一步开展了对葡萄糖的检测。以金纳米簇荧光强度的变化值F/F_(0)为纵坐标,过氧化氢或葡萄糖浓度为横坐标,实现了对过氧化氢和葡萄糖的灵敏检测,线性范围分别为10~100和10~2.0μmol·L^(-1),检测下限分别为2.8和3.1μmol·L^(-1)。选择4种其他糖类化合物和5种金属离子作为干扰物质,均不会抑制半胱氨酸对金纳米簇的荧光猝灭效应,表明该方法具有很好的选择性。用该方法成功检测了胎牛血清样品中的葡萄糖,加标回收率为94.5%~112.7%。此外,该方法可拓展到其他基于酶催化产生过氧化氢体系的分析物检测,如胆固醇、辣根过氧化物酶等,为过氧化氢相关反应的分析提供了一种通用、简便的方法,在临床诊断、食品科学和环境分析等领域具有潜在的应用价值。

关键词：金纳米簇氧化反应调控荧光法过氧化氢葡萄糖