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Chinese Chemical Letters 2024年第3期35卷 419-422页

作者： Cheng Wu Yixuan Liu Chunsheng xiao chenyang Hu Xuan Pang Xuesi Chen Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

A new strategy for the metal-free coordination–insertion ring-opening polymerization of tetrahydrofuran by the central metalloid Boron has been first ***(pentafluorophenyl)(phenoxy)borane was used as a catalyst for the polymerization reaction *** polytetrahydrofuran with high molecular weight and narrow molecular weight distribution could be *** proposed mechanism was studied by MALDI-TOF,ESI-MS and O-18 isotope labeling analyses as a metal-free coordination insertion mechanism.

关键词： Metal-free catalyst Bis(pentafluorophenyl)(phenoxy)borane Coordination–insertion mechanism Ring-opening polymerization Polytetrahydrofuran

Defined organic-octamolybdate crystalline superstructures derived Mo_(2)C@C as efficient hydrogen evolution electrocatalysts

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Chinese Chemical Letters 2024年第6期35卷 201-205页

作者： Jiao Li chenyang Zhang Chuhan Wu Yan Liu Xuejian Zhang xiao Li Yongtao Li Jing Sun Zhongmin Su School of Materials Science and Engineering Jilin Jianzhu UniversityChangchun 130018China School of Chemical and Environmental Engineering Changchun University of Science and TechnologyChangchun 130022China

Hydrogen evolution electrocatalysts derived from metal-organic crystalline frameworks can inherit the merits of ordered and adjustable structures with high surface *** this paper,organic-octamolybdate crystalline superstructures(OOCS)with a fixed stoichiometric ratio of Mo_(8)(L)_(2) and high Mo content(>40 wt%)were synthesized using flexible ligands with controllable lengths(named as OOCS-1-3).Then,molybdenum carbides coated with carbon layers as electrocatalysts(Mo_(2)C@C-1-3)can be obtained directly from a one-step high-temperature carbonization process using OOCS-1-3 as *** a typical example,Mo_(2)C@C-3 exhibits satisfactory hydrogen evolution activity with a low overpotential of 151 m V(1.0 mol/L KOH)at 10 m A/cm^(2) and stability for 24 *** electrocatalytic activity is mainly from the synergistic interactions between the carbon layers and molybdenum carbide ***,compared with the initial content of C,N,Mo in OOCS and Mo_(2)C@C,the catalytic activity increases with the N *** work makes organic-octamolybdate crystalline superstructures used as general precursors to product high Mo content electrocatalysts applied in energy storage and conversion fields.

关键词： Molybdenum carbides Electrocatalysts Organic-octamolybdate crystalline superstructures Synergistic interactions Hydrogen evolution reaction(HER)

Scalable production of mesoporous titanium nanoparticles through sequential flash nanocomplexation

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Chinese Chemical Letters 2024年第4期35卷 303-309页

作者： Feng Cui Fangman Chen xiaochun Xie chenyang Guo Kai xiao Ziping Wu Yinglu Chen Junna Lu Feixia Ruanb Chuanxu Cheng Chao Yang Dan Shao School of Biomedical Sciences and Engineering South China University of TechnologyGuangzhou International CampusGuangzhou 511442China Institutes for Life Sciences School of MedicineSouth China University of TechnologyGuangzhou 510006China School of Biology and Biological Engineering South China University of TechnologyGuangzhou 510006China Department of Orthopedics Academy of Orthopedics-Guangdong ProvinceOrthopedic Hospital of Guangdong ProvinceGuangdong Provincial Key Laboratory of Bone and Joint Degenerative DiseasesThe Third Affiliated Hospital of Southern Medical UniversityGuangzhou 510665China National Engineering Research Center for Tissue Restoration and Reconstruction South China University of TechnologyGuangzhou 510006China

Mesoporous titanium nanoparticles(MTNs) have emerged as an important porous semiconductor owning to their large surface area and unique electronic/optical properties. However, the fundamental research for rational manufacturing MTNs in a highly scalable manner remains a challenge. In this study, we report a two-step flash nanocomplexation(FNC) approach to large-scalable generate MTNs through the sequential combination of two multi-inlet vortex mixers. By optimizing the concentrated titanium precursor,polyethylene glycol(PEG)-functionalized silane amount and p H, we have been able to produce MTNs with small particle size(31.5 nm), larger surface area(416.9 m^(2)/g) and pore volume(0.59 cm^(3)/g). Different from the traditional MTNs bulk, FNC-produced MTNs exhibited well-controlled manner and exceptional photocatalytic and antibacterial properties. Importantly, the optimized MTNs outperformed commercial P25 not only in protecting ultraviolet A(UVA)-exposed skin, but also in treating P. aeruginosa-infected wound. We believe that the high controllability and scalability of sequential flash nanocomplexation method offers great opportunities in enhancing the performance of mesoporous titanium nanoparticles.

关键词： Mesoporous titanium nanoparticles Flash nanocomplexation Photocatalytic Antibacterial Sequential

Study on the Treatment of Common Mental Health Problems Among Adolescents in Contemporary China's Mainland

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Journal of Contemporary Educational Research 2022年第9期6卷 16-22页

作者： chenyang xiao University of Hong Kong Daqing 163000Heilongjiang ProvinceChina

With the continuous development of society,the competition among the members of the society is becoming increasingly fierce,and the culture is becoming more *** view of this,adolescents are prone to psychological problems in the process of growing *** present,about 15%of junior high school and about 19%of senior high school students in China suffer from psychological ***’psychological problems have become a serious social *** on this,from the perspective of socialization,this paper studies the main psychological problems of teenagers,explores their origin and finds out corresponding countermeasures,in order to provide some reference for preventing and solving common psychological problems of teenagers.

关键词： Socialization Adolescents Mental health Problems and countermeasures

ER5356焊丝用于7075铝合金MIG焊接头热处理性能

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材料工程 2024年第3期52卷 149-157页

作者：王晨阳刘骁李小平朱彬江苏理工学院江苏省先进材料设计与增材制造重点实验室江苏常州213000

采用MIG焊使用ER5356焊丝进行3 mm厚7075铝合金对接焊,焊后接头进行T6热处理。通过光学显微镜、X射线衍射仪、扫描电镜与能谱仪结合室温拉伸、显微硬度与电化学腐蚀分析接头组织、力学性能与耐蚀性。结果表明:焊接时熔池流动将母材熔化... 详细信息

采用MIG焊使用ER5356焊丝进行3 mm厚7075铝合金对接焊,焊后接头进行T6热处理。通过光学显微镜、X射线衍射仪、扫描电镜与能谱仪结合室温拉伸、显微硬度与电化学腐蚀分析接头组织、力学性能与耐蚀性。结果表明:焊接时熔池流动将母材熔化部位的Zn,Cu等合金元素带入焊缝,析出MgZn_(2)与AlCuMg相,成为焊缝进行热处理强化的基础;热处理后,大部分析出相溶入基体形成固溶+时效强化,接头抗拉强度提升20%,焊缝硬度提升18.4%,耐蚀性提高。但由于从母材流入焊缝的合金元素含量有限,焊丝与母材力学性能的差异与热影响区软化现象无法消除。

关键词： 7075铝合金 MIG焊热处理焊缝组织力学性能耐蚀性

气相二氧化硅/三元无机水合盐定型相变材料的制备及性能表征

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化工新型材料 2024年第5期52卷 245-248,254页

作者：肖力光朱晨阳吉林建筑大学材料科学与工程学院长春130118

以气相二氧化硅作为多孔吸附材料,对十二水磷酸氢二钠/五水偏硅酸钠/十水碳酸钠低共熔相变材料进行封装,通过控制气相二氧化硅含量,制备出不同吸附量的气相二氧化硅/三元无机水合盐定型相变材料。通过差示扫描量热仪、扫描电子显微镜、... 详细信息

以气相二氧化硅作为多孔吸附材料,对十二水磷酸氢二钠/五水偏硅酸钠/十水碳酸钠低共熔相变材料进行封装,通过控制气相二氧化硅含量,制备出不同吸附量的气相二氧化硅/三元无机水合盐定型相变材料。通过差示扫描量热仪、扫描电子显微镜、傅里叶变换红外光谱仪、X射线衍射仪和热重分析仪等多种测试手段,对定型相变材料的性能和结构进行表征。研究结果表明:气相二氧化硅的最佳含量为25%(质量分数),该条件下定型相变材料相变焓为95.96J/g;三元无机水合盐相变材料与气相二氧化硅只是单纯的物理混合,并未发生化学反应产生新物质,制备的定型相变热稳定性较好。

关键词：相变蓄能气相二氧化硅定型相变材料低碳节能

质疑国税发[2001]142号文中当期成本费用的计算公式

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涉外税务 2006年第8期 79-80页

作者：陈怡肖晨阳赣州市技师学院江西赣州341000 赣州市国家税务局江西赣州341000

现行计算方法的缺陷

关键词：总成本费用公式国税企业所得税单位工程国家税务总局销售面积计算方法管理问题开发经营

考虑纤维波纹度的单向复合材料代表性体积元生成算法

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机械工程学报 2024年第8期60卷 186-195页

作者：谢晨阳黄鲛肖光明张贤杰王俊彪李玉军西北工业大学机电学院西安710072 中国航空工业集团公司雷华电子技术研究所无锡214063 中航西安飞机工业集团股份有限公司西安710089

提出一种单向纤维增强复合材料(Unidirectional fiber reinforced polymer,UD-FRP)周期性高保真代表性体积元(Representative volume element,RVE)的创建算法。首先基于随机游走算法,采用贝塞尔(Bézier)曲线表征纤维形态,使曲线各控制... 详细信息

提出一种单向纤维增强复合材料(Unidirectional fiber reinforced polymer,UD-FRP)周期性高保真代表性体积元(Representative volume element,RVE)的创建算法。首先基于随机游走算法,采用贝塞尔(Bézier)曲线表征纤维形态,使曲线各控制点处的切线方向的统计分布服从多变量冯·米塞斯-费歇尔(Von-MISES FISCHER)函数,创建出初步的软核模型。进而基于力偏置算法,在保证RVE内部纤维不产生过度扭曲的前提下,调整纤维间的重叠,创建出对应的硬核模型。调整过程中,通过引入三维近邻列表算法,大幅提高算法效率。最后对所创建的含有纤维波纹度特征的RVE模型进行了横向剪切渐进损伤分析,用以揭示该方法的研究价值及应用领域。结果表明,该方法能够快速有效地创建不同尺寸及纤维波纹度的RVE几何构型,这种含有波纹度特征的纤维构型会对UD-FRP的横向剪切性能产生一定影响,纤维波纹度越大,UD-FRP的横向剪切强度越大。

关键词：单向纤维增强复合材料纤维波纹度随机游走周期性边界条件近邻列表算法力偏置算法横向剪切

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凹凸棒石在生物医学领域中的应用研究进展

硅酸盐学报 2024年第1期52卷 359-370页

作者：孙伟王申金刘小溪张晨阳王嵘韩明君肖扬阳燕刘威中南大学资源加工与生物工程学院长沙410083 中南大学国家代谢性疾病临床医学研究中心糖尿病免疫学教育部重点实验室湘雅二医院代谢内分泌科长沙410011 中南大学湘雅口腔医学院长沙410000 中南大学湘雅二医院普外科长沙410011

凹凸棒石是一种具有2:1型链层状结构的硅酸盐黏土矿物,针棒状的晶体长度约为0.5~5.0μm,是一种不可再生的天然纳米材料。凹凸棒石特殊的结构赋予了它优异的吸附性,胶体性等性质。凹凸棒石作为绿色的天然矿物材料,具有良好的生物相容性,... 详细信息

凹凸棒石是一种具有2:1型链层状结构的硅酸盐黏土矿物,针棒状的晶体长度约为0.5~5.0μm,是一种不可再生的天然纳米材料。凹凸棒石特殊的结构赋予了它优异的吸附性,胶体性等性质。凹凸棒石作为绿色的天然矿物材料,具有良好的生物相容性,并且储量丰富,价格低廉,所以在生物医药领域有着广泛的应用潜力。本文综述了凹凸棒石在生物抗菌、药物输送、骨组织工程、伤口敷料等方面的应用研究进展,并对其未来的应用前景进行了展望。本文对于凹凸棒石的生物医学应用研究具有重要的参考价值。

关键词：凹凸棒石硅酸盐矿物纳米材料生物医药复合材料