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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 college of chemistry and Chemical {2. Hunan University of Science and Technology Xiangtan China State Key Laboratory of Powder Metallurgy Central South University Changsha 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

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 Chemical {2. 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 line and exhibited stronger Wnt and HIF1 dual signaling 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 applied 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

Seamlessly Merging the Capacity of P into Sb at Same Voltage with Maintained Superior Cycle Stability and Low-temperature Performance for li-ion Batteries

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Energy & Environmental Materials 2023年第2期6卷 195-201页

作者： Yaqing Wei Jun He Jie Zhang Mingyang ou Yanpeng Guo Jiajun Chen Cheng Zeng Jia Xu Jiantao Han Tianyou Zhai Huiqiao {2. State Key Laboratory of Materials Processing and Die&Mould technology School of Materials Science and EngineeringHuazhong University of Science and Technology(HUST)Wuhan 430074China State Key Laboratory of Marine Resource Utilization in South china Sea Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti ResourcesCollege of Materials Science and EngineeringHainan UniversityHaikou 570228China Key Laboratory of Advanced Energy Materials chemistry(Ministry of Education) Nankai UniversityTianjin 300071China

Among the alloying-type anodes,elemental Sb possesses the suitable yet safe plateau,simple lithiation pathway,small voltage polarization,high conductivity,and superior cycle ***,challenge is that its intrinsic capacity is rather low(660 mAh g^(-1)),lid solution ***,the enlistment of P is found greatly enlarge the capacity from 660 to 993 mAh g^(-1) for such Sb_(30)P_(30) solid solution,while maintaining a single and stable discharge plateau(~0.79 V)similar to elemental *** experimental characterizations including XPS,PDF,Raman,and EDS mapping reveal that in such a material the P and Sb atoms have interacted with each other to form a homogenous solid solution alloy,rather than a simple mixing of the two ***,the Sb_(30)P_(30) exhibits superior rate performances(807 mAh g^(-1) at 5000 mA g^(-1))and cyclability(82. mAh g^(-1) remained after 300 cycles).Furthermore,such Sb_(60-x)P_(x) alloys can even deliver 62. mAh g^(-1) at30℃,which can be served as the alternative anode materials for high-energy and low-temperature *** unique seamless integration strategy based on solid solution chemistry can be easily leveraged to manipulate the capacity of other electrode materials at similar voltage.

关键词： alloy anode antimony lithium-ion batteries low-temperature performance phosphorus

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新晶科技有限公司

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... 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

Luminescence property and magnetic resonance imaging of Gd_(2.O_(3):Tb^(3+) nanocrystals doped with Zn^(2.),li^(+)

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Rare Metals 2021年第8期40卷 2049-2058页

作者： Rong Fu Yan-Yan Hu Hui-Na Qiao Chun-lin Yang Hao Yin Mei-Gui ou college of Materials and Metallurgy University of GuizhouGuiyang550025China National Local Co-construction engineering Laboratory for High Performance Metal Structure Material and Manufacture technology Guiyang550025China college of chemistry and Materials {2. Guiyang UniversityGuiyang550003China Department of Neurosurgery Guizhou Provincial People’s HospitalGuiyang550002China

Gd_(2.O_(3):Tb^(3+) nanocrystal co-doped with Zn^(2.)and li^(+) was prepared by the combination of polyol and solid-phase *** synthesized nanoparticles were characterized by X-ray diffraction(XRD),field emission scanning electron microscopy(FESEM),transmission electron microscopy(TEM),photoluminescence(PL)spectra and magnetic resonance imaging(MRI).The results revealed that both Gd_(2.O_(3):Tb^(3+)/Zn^(2.) and Gd_(2.O_(3):Tb^(3+)/li^(+) had cubic unit structures with a spherical shape,and the fluorescence intensity of the nanoparticles reached a maximum at a doping concentration of0.050 mmol%for Zn^(2.) and 2.mol%for li^(+),*** addition,the T_(1)/T_(2.(longitudinal/transverse relaxation time)-weighted MRI signals got enhanced due to the increased longitudinal relaxivity(r1)and transverse relaxivity(r2.after the doping by metal ***,the materials reported here can be used for fluorescence and MR bimodal imaging,as tracers and for fluorescence detections.

关键词： Gd_(2.O_(3):Tb^(3+) Zn^(2.)/li^(+)doping Luminescent property Magnetic resonance imaging Nanomaterials

A versatile strategy to activate self-sacrificial templated li_(2.MnO_(3) by defect engineering toward advanced lithium storage

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Journal of Energy chemistry 2023年第10期85卷 164-180,I0007页

作者： Jian-En Zhou Yanhua Peng Xiaoyan Sang Chunlei Wu Yiqing liu Zhijian Peng Hong ou Yongbo Wu Xiaoming lin Yuepeng Cai Guangzhou Key Laboratory of Materials for Energy Conversion and Storage Joint Laboratory of Energy and Materials Chemistry(South China Normal University-Guangzhou Tianci New Materials Co.Ltd.)Key Laboratory of Theoretical Chemistry of EnvironmentMinistry of EducationSchool of ChemistrySouth China Normal UniversityGuangzhou 510006GuangdongChina National engineering Research Center for Carbohydrate Synthesis Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of EducationJiangxi Normal UniversityNanchang 330022JiangxiChina Guangzhou Huifu Research Institute Co. LtdNanxiang San LuGuangzhou 510663GuangdongChina Guangdong Provincial Key Laboratory of Quantum engineering and Quantum Materials National Demonstration Center for Experimental Physics EducationSchool of Physics and Telecommunication EngineeringSouth China Normal UniversityGuangzhou 510006GuangdongChina

Despite the dazzling theoretical capacity,the devasting electrochemical activity of li_(2.MnO_(3)(LMO)caused by the difficult oxidation of Mn4+impedes its practical application as the lithium-ion battery(liB)*** efficacious activation of the li_(2.MnO_(3) by importing electrochemically active Mn3+ions or morphological engineering is instrumental to its lithium storage activity and structural integrity upon ***,we propose a conceptual strategy with metal-organic frameworks(MOFs)as self-sacrificial templates to prepare oxygen-deficient li_(2.MnO_(3)(O_v-LMO)for exalted lithium storage *** to optimized morphological features,LMO materials derived from Mn-BDC(H_(2.BDC=1,4-dicarboxybenzene)delivered superior cycling/rate performances compared with their counterparts derived from Mn-BTC(H_(3)BTC=1,3,5-benzenetricarboxylicacid)and Mn-PTC(H_(4)PTC=pyromellitic acid).Both experimental and theoretical studies elucidate the efficacious activation of primitive LMO materials toward advanced lithium storage by importing oxygen ***,O_v-LMO derived from Mn-BDC(O_v-BDC-LMO)delivered intriguing reversible capacities(179.2.mA h g^(-1)at 2. mA g^(-1)after 2.0 cycles and 100.1 mA h g^(-1)at 80 mA g^(-1)after 300 cycles),which can be attributed to the small particle size that shortens pathways for li+/electron transport,the enhanced redox activity induced by abundant oxygen vacancies,and the optimized electronic configuration that contributes to the faster lithium *** work provides insights into the rational design of LMO by morphological and atomic modulation to direct its activation and practical application as an advanced liB cathode.

关键词： li_(2.MnO_(3) Metal-organic framework Oxygen vacancy lithium-ion battery Electrochemical activity

紫丁香苷调控PI3K/Akt/mTOR信号通路诱导乳腺癌细胞凋亡的研究

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生物化学与生物物理进展 2023年第12期50卷 2954-2965页

作者：石雅倩李鑫黄思源欧明坤李红娜卢敏耿梦丽欧叶涛桂林医学院基础医学院桂林541001 广西师范大学药物资源化学与分子工程国家重点实验室桂林541004 新乡医学院三全学院新乡453000 佳木斯大学临床医学院佳木斯154002

目的研究紫丁香苷的抗乳腺癌作用及分子机制,为紫丁香苷的临床应用提供理论依据。方法MTT检测紫丁香苷对乳腺癌细胞增殖的抑制作用;台盼蓝、TUNEL和Annexin V-FITC/PI染色检测细胞的凋亡状况,Western bolt检测Caspase-3的活化情况,判断... 详细信息

目的研究紫丁香苷的抗乳腺癌作用及分子机制,为紫丁香苷的临床应用提供理论依据。方法MTT检测紫丁香苷对乳腺癌细胞增殖的抑制作用;台盼蓝、TUNEL和Annexin V-FITC/PI染色检测细胞的凋亡状况,Western bolt检测Caspase-3的活化情况,判断细胞凋亡是否发生;检测凋亡相关蛋白B淋巴细胞瘤2.Bcl-2.的表达,结合JC-1染色探讨紫丁香苷对线粒体凋亡途径的影响;运用PI3K激动剂Recilisib做对比,qRT-PCR和Western bolt检测紫丁香苷调控PI3K/Akt/mTOR通路诱导癌细胞凋亡的作用。结果紫丁香苷对乳腺癌细胞的增殖具有时间和剂量依赖的抑制作用,能诱导癌细胞发生凋亡。进一步研究发现,紫丁香苷处理后,细胞内Caspase-3被激活,Bcl-2.达下降,线粒体膜电位明显丧失,PI3K、Akt和mTOR的mRNA与蛋白质水平表达无明显变化,但蛋白质磷酸化水平明显下降;Recilisib处理后部分抵消了紫丁香苷对乳腺癌细胞凋亡的作用。结论紫丁香苷对乳腺癌细胞MDA-MB-{2.和MCF-7具有良好的抑制作用,其通过抑制PI3K/Akt/mTOR信号通路的活化来抑制细胞增殖并诱导细胞发生线粒体途径的凋亡。紫丁香苷是具有开发潜力的抗乳腺癌药物。

关键词：紫丁香苷乳腺癌细胞凋亡

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 chemical ***,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

短乳杆菌对Cr^(3+)的吸附及动力学和热力学拟合

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环境化学 2019年第3期38卷 626-634页

作者：代启虎李冉葛俊苗张雯李柏林欧杰上海海洋大学食品学院上海201306 农业部水产品贮藏保鲜质量安全风险评估实验室(上海) 上海201306 上海水产品加工及贮藏工程技术研究中心上海201306

研究了Lactobacillus brevis对水溶液中Cr(Ⅲ)的吸附作用.考察了初始pH值、接触时间、初始Cr(Ⅲ)浓度、菌体浓度和温度对Cr(Ⅲ)吸附效果的影响.结果表明,在较低的pH、温度和初始Cr(Ⅲ)离子浓度条件下,菌株对Cr(Ⅲ)离子的吸附量较低.在... 详细信息

研究了Lactobacillus brevis对水溶液中Cr(Ⅲ)的吸附作用.考察了初始pH值、接触时间、初始Cr(Ⅲ)浓度、菌体浓度和温度对Cr(Ⅲ)吸附效果的影响.结果表明,在较低的pH、温度和初始Cr(Ⅲ)离子浓度条件下,菌株对Cr(Ⅲ)离子的吸附量较低.在试验条件下,溶液初始pH、温度和初始Cr(Ⅲ)离子浓度的升高,均能提高菌株对Cr(Ⅲ)离子的吸附量.在温度为40℃、pH 6和初始Cr(Ⅲ)离子浓度为2.0 mg·L^(-1)时,菌株吸附量最大.随菌体浓度升高,单位浓度菌体对Cr(Ⅲ)离子吸附量降低,但总吸附量增大,菌体浓度为6 g·L^(-1)吸附量最大.菌株对Cr(Ⅲ)离子吸附较快,接触时间为1 h就达到平衡.用Langmuir、Freundlich、Redlich-Peterson和Temkin吸附模型进行拟合,相关的回归系数表明,吸附过程拟合Langmuir吸附模型比Freundlich、Redlich-Peterson和Temkin吸附模型好.用Elovich、准一级、准二级动力学拟合,动力学试验数据与Lagergren准二级动力学方程的拟合度最佳.

关键词：乳酸菌 Cr(Ⅲ) 吸附动力学吸附热力学