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石墨烯-ZnIn_2S_4纳米复合微球的制备及光催化产氢活性

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无机材料学报 2015年第7期30卷 713-718页

作者：周民杰张娜侯朝辉湖南理工学院化学化工学院岳阳414006

采用光催化还原法制备了石墨烯-Zn In2S4纳米复合微球。采用XRD、SEM、TEM、FT-IR、XPS和DRS等手段对样品进行表征,结果表明,经过光催化还原处理后氧化石墨被还原成石墨烯,Zn In2S4纳米微球负载在石墨烯表面。光催化产氢的实验结果表明... 详细信息

采用光催化还原法制备了石墨烯-Zn In2S4纳米复合微球。采用XRD、SEM、TEM、FT-IR、XPS和DRS等手段对样品进行表征,结果表明,经过光催化还原处理后氧化石墨被还原成石墨烯,Zn In2S4纳米微球负载在石墨烯表面。光催化产氢的实验结果表明,当石墨烯含量为2.0wt%、光催化还原时间为24 h时,石墨烯-Zn In2S4纳米复合微球在模拟太阳光下产氢量达到1540.8μmol,是纯Zn In2S4纳米微球的9.8倍。增强光催化性能的原因归结为石墨烯在复合光催化剂中起到了电子快速传输作用,同时还对纳米复合微球光催化产氢反应机理进行了分析讨论。

关键词：光催化还原法 ZnIn2S4纳米微球石墨烯产氢

Changes in P2Y purinoreceptor-mediated intracellular calcium signal pathways results in inositol-1, 4, 5-triphosphate-sensitive calcium stores in rat small trigeminal ganglion neurons

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Neural Regeneration Research 2010年第12期5卷 906-910页

作者： Yuanyin Wang Andong Liu jie Lei min Xie Zhongwen Li Liecheng Wang Stomatological Hospital Anhui Medical University Hefei 230032 Anhui Province China Department of Physiiology School of Basic Medical Science Anhui Medical University Hefei 230032 Anhui Province China

BACKGROUND： Most of the currently available information on purinergic receptors （P2Rs） involved in pain transmission is based on results obtained in dorsal root ganglion or the spinal cord. However, the mechanism of P2Rs in trigeminal neuralgia remains unclear. OBJECTIVE： To investigate changes in the P2R-mediated calcium signaling pathway in nociceptive trigemJnal ganglion neurons. DESIGN, TIME AND SETTING： In vitro experiments were conducted at the Patch-Clamp Laboratory of Comprehensive Experiment Center of Anhui Medical University, China from September 2008 to June 2009. MATERIALS： Thapsigargin, caffeine, suramin, and adenosine 5＇-triphosphate were purchased from Sigma, USA. METHODS： Using Fura-2-based microfluorimetry, intracellular calcium concentration （[Ca^2＋]i） was measured in freshly isolated adult rat small trigeminal ganglion neurons before and after drug application. MAIN OUTCOME MEASURES： Fluorescent intensities were expressed as the ratio F340/F380 to observe [Ca^2＋]i changes. RESULTS： In normal extracellular solution and Ca^2＋-free solution, application of thapsigargin （1 μmol/L）, a sarcoplasmic reticulum Ca^2＋ pump adenosine 5＇-triphosphate inhibitor, as well as caffeine （20 mmol/L）, a ryanodine receptor agonist, triggered [Ca^2＋]i increase in small trigeminal ganglion neurons. A similar response was induced by application of adenosine 5＇-triphosphate （100 μmol/L）. In Ca^2＋-free conditions, adenosine 5＇-triphosphate-induced [Ca^2＋]i transients in small trigeminal ganglion neurons were inhibited in cells pre-treated with thapsigargin （P 〈 0.01）, but not by caffeine （P 〉 0.05）. In normal, extracellular solution, adenosine 5＇-triphosphate-induced [Ca^2＋]i transients in small trigeminal ganglion neurons were partly inhibited in cells pre-treated with thapsigargin （P 〈 0.05）. CONCLUSION： Inositol-1,4, 5-triphosphate （IP3）- and ryanodine-sensitive Ca^2＋ stores exist in rat nociceptive trigeminal ganglion neurons. Two pathways are involved in the purinorec

关键词： calcium stores cytoplasmic calcium trigeminal ganglion adenosine 5'-triphosphate purinergic receptors neurotrophic factor trigeminal neuralgia neural regeneration

Improvements to conventional X-ray tube-based cone-beam computed tomography system

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Nuclear Science and Techniques 2018年第3期29卷 156-164页

作者： Cui Zhang Xiao-Dong pan Hong-jie Shang Yan-Hong Luo Gong-Ping Li School of Nuclear Science and Technology Lanzhou University

Conventional X-ray tube-based cone-beam computed tomography(CX-CBCT) systems have great potential in industrial applications. Such systems can rapidly obtain a three-dimensional(3D) image of an *** X-ray tubes fulfill the requirements for industrial applications, because of their high tube voltage and power. Continuous improvements have been made to CX-CBCT systems, such as imaging time shortening,acquisition strategy optimization, and imaging software development, etc. In this study, a CX-CBCT system is developed. Additionally, some improvements to the CX-CBCT system are proposed based on the hardware conditions of the X-ray tube and detector. A near-detector(ND)geometry condition is employed to obtain a sharper image and larger detection area. An improved acquisition strategy is proposed to simplify operations and reduce total imaging time. In the ND geometry condition, a simplified method called FBP slice stacking(SS-FBP) is proposed, which can be applied to 3D image reconstruction. SS-FBP is timesaving relative to traditional methods. Furthermore, imaging software for the CX-CBCT system is developed in the MATLAB environment. Several imaging experiments were performed. The results suggest that the CX-CBCT system works properly, and that the above improvements are feasible and practical.

关键词： Cone-beam CT Conventional X-ray tube Nondestructive testing X-ray imaging

基于SDAI的STEP-NC数控加工程序信息提取与建模

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浙江大学学报（工学版） 2007年第9期41卷 1572-1577,1591页

作者：周刚邬义杰潘晓弘浙江大学机械与能源工程学院浙江杭州310027

基于STEP-NC应用数据模型和标准数据存储界面(SDAI),通过构造数据字典模型、实体实例数据结构模型和零件实例数据结构模型,建立了描述STEP-NC加工程序的零件-实体分级数据结构,实现了STEP-NC数据到C++数据的转换.采用步进式构造方式提取... 详细信息

基于STEP-NC应用数据模型和标准数据存储界面(SDAI),通过构造数据字典模型、实体实例数据结构模型和零件实例数据结构模型,建立了描述STEP-NC加工程序的零件-实体分级数据结构,实现了STEP-NC数据到C++数据的转换.采用步进式构造方式提取STEP-NC程序信息,通过回溯递归方法构造了STEP-NC单元实体实例,进而匹配实体属性项内容,建立了零件级的数据结构.该方法避免了SDAI迟联编在实体建立和实体实例建立之间的时序矛盾.最后开发了信息提取原型系统,实例论证表明,该系统能够识别STEP-NC数控加工程序,并显示零件单特征几何形体.

关键词： STEP—NC 信息提取数据结构 SDAI

三维方腔温盐双扩散的格子Boltzmann方法数值模拟

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物理学报 2006年第9期55卷 4774-4782页

作者：卢玉华詹杰民中山大学应用力学与工程系广州510275

研究了温盐双扩散系统的多组分格子Boltzmann方法.通过对二维方腔的温盐双扩散系统的数值模拟,检验了方法的可行性及有效性,所得到的结果与差分法结果符合良好,继而将此方法推广到三维,建立了三维温盐双扩散系统的格子Boltzmann方法,对... 详细信息

研究了温盐双扩散系统的多组分格子Boltzmann方法.通过对二维方腔的温盐双扩散系统的数值模拟,检验了方法的可行性及有效性,所得到的结果与差分法结果符合良好,继而将此方法推广到三维,建立了三维温盐双扩散系统的格子Boltzmann方法,对三维方腔双扩散问题进行了模拟和分析,并与差分法模拟的结果进行了比较,结果令人满意.最后,分析了格子Boltzmann方法在模拟双扩散对流问题时存在的局限性.

关键词：格子Boltzmann方法温盐双扩散 Boussinesq近似数值模拟

3,6-二肼基-1,2,4,5-四嗪及其盐的合成与表征

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含能材料 2006年第2期14卷 116-117,122页

作者：潘劼何金选陶永杰中国航天科技集团公司四院四十二所湖北襄樊441003

以三氨基胍盐酸盐和2,4-戊二酮为原材料,通过成环反应,氧化脱氢,肼基取代,三步合成了3,6-二肼基-1,2,4,5-四嗪,同时,对3,6-二肼基-1,2,4,5-四嗪的含能盐的合成进行了研究。对文献报道的反应路线进行了适当的放大研究。通过红外光谱分析... 详细信息

以三氨基胍盐酸盐和2,4-戊二酮为原材料,通过成环反应,氧化脱氢,肼基取代,三步合成了3,6-二肼基-1,2,4,5-四嗪,同时,对3,6-二肼基-1,2,4,5-四嗪的含能盐的合成进行了研究。对文献报道的反应路线进行了适当的放大研究。通过红外光谱分析、元素分析、质谱分析和1HNMR等方法对产物的结构特征进行了鉴定。

关键词：有机化学 3,6-二肼基-1,2,4,5-四嗪合成四嚷高氮化合物

Crystallization, Mechanical and Flame-retardant Properties of Poly(lactic acid) Composites with DOPO and DOPO-POSS

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Chinese Journal of Polymer Science 2018年第7期36卷 871-879页

作者： Lin Jia Wen-Chao Zhang Bin Tong Rong-jie Yang National Engineering Research Center of Flame Retardant Materials School of Materials Science and Engineering Beijing Institute of Technology

Poly（lactic acid）（PLA） composites with 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide （DOPO） and DOPO- containing polyhedral oligomeric silsesquioxane （DOPO-POSS） were prepared via melting extrusion and injection molding. The crystallization, mechanical, and flame-retardant properties of PLA/DOPO and PLA/DOPO-POSS were investigated by differential scanning calorimetry （DSC）, X-ray diffraction （XRD）, tensile testing, thermogravimetric analysis （TGA）, limiting oxygen index （LOI）, and cone calorimeter test. The DSC results showed that the DOPO added could act as a plasticizer as reflected by lower glass transition temperature and inhibited crystallization of part of the PLA; the DOPO-POSS acted like a filler in the PLA matrix and slightly improved the crystallinity of the PLA matrix. The XRD and DSC analyses indicated that the PLA composites by cold molding injection were amorphous, and the PLA composites following a heat treatment in an oven at 120 ℃for 30 min achieved crystallinity. All the PLA and its composites after heat treatment had improved mechanical properties. The thermogravimetric analysis （TGA） tests showed that the PLA, DOPO and DOPO-POSS decomposed separately in the PLA/DOPO and PLA/DOPO-POSS, respectively. The cone calorimeter tests offered clear evidence that addition of the DOPO-POSS resulted in an evident reduction of 25% for the peak of heat release rate （p-HRR）. It was also confirmed that the crystalline flame-retardant PLA composites after heat treatment had better flame retardant properties than the amorphous PLA composites prepared by the cold molding.

关键词： Poly(lactic acid) DOPO-POSS Crystallization Mechanical property Flame retardancy

基于复合规则的Interbay物料运输系统多目标调度方法

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计算机集成制造系统 2016年第8期22卷 1965-1976页

作者：张洁潘聪秦威孙寅斌上海交通大学机械与动力工程学院上海200240

为了满足晶圆制造Interbay物料运输系统的全局优化要求,提出基于复合规则的Interbay物料运输系统多目标调度方法。充分考虑各运输设备之间的约束关系,建立了Interbay物料运输系统的多目标调度模型。提出基于遗传规划的复合规则生成方法... 详细信息

为了满足晶圆制造Interbay物料运输系统的全局优化要求,提出基于复合规则的Interbay物料运输系统多目标调度方法。充分考虑各运输设备之间的约束关系,建立了Interbay物料运输系统的多目标调度模型。提出基于遗传规划的复合规则生成方法,该方法将晶圆工件的属性参数与四种基本运算符号按照二叉树的结构进行编码,再通过选择、交叉、变异以及基于d-best策略的λ-Interchange局部搜索方法,寻找具有最佳适应度的复合调度规则。为了对大量个体进行快速评价,设计了基于物料运输表的适应度值估算方法。仿真实验结果表明,与文献中的Interbay物料运输调度方法相比,基于所提算法生成的复合调度规则能够对工件的平均加工周期、平均搬运时间、平均交货期满足率等多个目标进行综合优化,同时表现出较好的鲁棒性。

关键词： Interbay物料运输系统调度多目标遗传规划

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官员任期、政策偏好与城市创新

科研管理 2023年第1期44卷 114-124页

作者：邓洁潘爽叶德珠广东外语外贸大学金融学院广东广州510006 江西财经大学会计学院江西南昌330013 暨南大学经济学院广东广州510632 暨南大学金融研究所广东广州510632

晋升锦标赛下,官员在有限任期内存在晋升预期差异,由此导致的短视行为的变化可能对创新产出造成影响。然而现有文献并未从官员晋升动机视角深入研究城市创新的制度动因,也未曾厘清官员任期等政治体制对创新活动的具体影响机制。本文利用... 详细信息

晋升锦标赛下,官员在有限任期内存在晋升预期差异,由此导致的短视行为的变化可能对创新产出造成影响。然而现有文献并未从官员晋升动机视角深入研究城市创新的制度动因,也未曾厘清官员任期等政治体制对创新活动的具体影响机制。本文利用2004—2016年285个城市的面板数据,通过多元统计回归分析,实证检验了官员任期如何通过经济增长目标影响城市创新的机制路径,并从土地财政、环境治理视角提出了新机制路径。研究发现:(1)相对于市长,市委书记任期对城市创新的影响更大,且呈现出显著的倒U型关系;(2)市委书记的更替显著抑制了城市创新水平的提升;(3)机制分析发现,市委书记的任期通过动态影响经济增长目标制定,土地财政依赖以及环境治理水平进而对城市创新产生影响。譬如当经济增长目标越高,官员越倾向于采用短视的扩张策略刺激经济,进而减少对创新活动的投入;(4)异质性分析发现在市场化条件较好,东部以及城市规模较大的地区,市委书记任期对创新的U型特征仍然显著。本文建议政府在推进财政分权体制改革时,应采用因地制宜的推进方式,将“有效市场”与“有为政府”更好地结合起来。本文研究结论丰富了晋升锦标赛理论的经验证据,有助于理解行政体制对高质量转型发展的影响。

关键词：官员任期城市创新晋升锦标赛高质量发展