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Substituent effect on the molecular stability,group interaction,detonation performance,and thermolysis mechanism of nitroamino-substituted cyclopentanes and cyclohexanes

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Science China Chemistry 2008年第12期51卷 1231-1245页

作者： qiu ling GONG XueDong JU XueHai XIAO HeMing Institute for Computation in Molecular and Material Science School of Chemical EngineeringNanjing University of Science and TechnologyNanjing 210094China Key Laboratory of Nuclear Medicine Ministry of HealthJiangsu Institute of Nuclear MedicineWuxi 214063China

Density functional theory (DFT) method has been employed to study the effect of nitroamino group as a substituent in cyclopentane and cyclohexane, which usually construct the polycyclic or caged nitra-mines. Molecular structures were investigated at the B3LYP/6-31G** level, and isodesmic reactions were designed for calculating the group interactions. The results show that the group interactions ac-cord with the group additivity, increasing with the increasing number of nitroamino groups. The dis-tance between substituents influences the interactions. Detonation performances were evaluated by the Kamlet-Jacobs equations based on the predicted densities and heats of formation, while thermal stability and pyrolysis mechanism were studied by the computations of bond dissociation energy (BDE). It is found that the contributions of nitroamino groups to the detonation heat, detonation velocity, detonation pressure, and stability all deviate from the group additivity. Only 3a, 3b, and 9a-9c may be novel potential candidates of high energy density materials (HEDMs) according to the quantitative cri-teria of HEDM (ρ≈ 1.9 g/cm3, D ≈ 9.0 km/s, P ≈ 40.0 GPa). Stability decreases with the increasing number of N-NO2 groups, and homolysis of N-NO2 bond is the initial step in the thermolysis of the title com-pounds. Coupled with the demand of thermal stability (BDE > 20 kcal/mol), only 1,2,4-trinitrotriazacy-clohexane and 1,2,4,5-tetranitrotetraazacyclohexane are suggested as feasible energetic materials. These results may provide basic information for the molecular design of HEDMs.

关键词： density functional theory (DFT) substituent effect monocyclic nitramine high energy density material (HEDM) group interaction detonation performance thermal stability bond dissociation energy (BDE)

Improved stability and oral bioavailability of Ganneng dropping pills following transforming lignans of herpeto- spermum caudigerum into nanosuspensions

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Chinese Journal of Natural Medicines 2018年第1期16卷 70-80页

作者： LI Juan-Juan CHENG ling SHEN Gang qiu ling SHEN Cheng-Ying ZHENG Juan XU Rong YUAN Hai-Long Department of Pharmacy Air Force General Hospital of PLA Beijing 100142 China Department of Pharmacy Guangyuan Central Hospital Guanyuan 628000 China Department of Pharmacy Shuangliu District Maternal and Child Health Hospital Chengdu 610075 China Chengdu Institute of Chinese Herbal Medicine Chengdu 610045 China

The present study was designed to improve storage stability and oral bioavailability of Ganneng dropping pills(GNDP) by transforming lignans of Herpetospermum caudigerum(HL) composed of herpetrione(HPE) and herpetin(HPN) into nanosuspension(HL-NS), the main active ingredient of GNDP, HL-NS was prepared by high pressure homogenization and lyophilized to transform into solid nanoparticles(HL nanoparticles), and then the formulated HL nanoparticles were perfused into matrix to obtain NS-GNDP by melting method. For a period of 3 months, the content uniformity, storage stability and pharmacokinetics test in vivo of NS-GNDP were evaluated and compared with regular GNDP at room temperature. The results demonstrated that uniformity of dosage units of NS-GNDP was acceptable according to the criteria of Chinese Pharmacopoeia 2015 J. Physical stability of NS-GNDP was investigated systemically using photon correlation spectroscopy(PCS), zeta potential measurement, and scanning electron microscopy(SEM). There was a slight increase in particles and PI of HL-NS re-dispersed from NS-GNDP after storage for 3 months, compared with new formulated NS-GNDP, which indicated a good redispersibility of the NS-GNDP containing HL-NS after storage. Besides, chemical stability of NS-GNDP was studied and the results revealed that HPE and HPN degradation was less when compared with that of GNDP, providing more than 99% of drug residue after storage for 3 months. In the dissolution test in vitro, NS-GNDP remarkably exhibited an increased dissolution velocity compared with GNDP and no distinct dissolution difference existed within 3 months. The pharmacokinetic study showed that HPE and HPN in NS-GNDP exhibited a significant increase in AUC0–t, Cmax and decrease in Tmax when compared with regular GNDP. These results indicated that NS-GNDP possessed superiority with improved storage stability and increased dissolution rate and oral bioavailability.

关键词： Ganneng dropping pills Lignans Herpetospermum caudigerum Nanosuspensions Stability Oral bioavailability

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权力对跨期决策的影响:希望的调节作用

中国临床心理学杂志 2024年第2期32卷 263-267,288页

作者：李晓明孟员叶秋伶湖南师范大学心理系长沙410081 湖南师范大学文化与社会心理研究中心长沙410081 湖南师范大学交叉科学研究院长沙410081 湖南师范大学认知与人类行为湖南省重点实验室长沙410081

目的:探讨权力对跨期决策的影响以及希望的调节作用。方法:研究一采用实验法操纵个体的希望感,并采用问卷测量一般权力感和跨期决策;研究二采用实验法操纵个体的权力水平,并采用问卷测量一般希望感和跨期决策。结果:相比于低权力者,高... 详细信息

目的:探讨权力对跨期决策的影响以及希望的调节作用。方法:研究一采用实验法操纵个体的希望感,并采用问卷测量一般权力感和跨期决策;研究二采用实验法操纵个体的权力水平,并采用问卷测量一般希望感和跨期决策。结果:相比于低权力者,高权力者更偏好远期选项。相比于低希望感个体,高希望感个体更偏好远期选项。希望可调节权力对跨期决策的影响,当个体处于中性情绪(研究一)或对于低希望感个体(研究二)而言,低权力者会比高权力者在跨期决策中表现得更加短视;但当个体处于希望情绪或对于高希望感个体而言,权力对跨期决策的影响消失。结论:希望能够缓冲低权力者在跨期决策中的短视倾向。

关键词：权力跨期决策希望

Excel规划求解在柱蚕水库库容曲线拟合中的应用

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广西水利水电 2024年第2期 114-116页

作者：仇灵南宁市邕宁区新江镇农林水利综合服务中心南宁530000

精准的库容曲线关系是科学合理实施水库调度的技术支撑,关系着水库的防洪安全和综合利用效益的充分发挥。本文介绍一种应用Excel软件中的图形处理和规划求解功能拟合柱蚕水库库容曲线,简化了手工绘制库容曲线的工作量,提高了定线效率及... 详细信息

精准的库容曲线关系是科学合理实施水库调度的技术支撑,关系着水库的防洪安全和综合利用效益的充分发挥。本文介绍一种应用Excel软件中的图形处理和规划求解功能拟合柱蚕水库库容曲线,简化了手工绘制库容曲线的工作量,提高了定线效率及库容曲线精度。经过拟合后的曲线和函数表达式可直接用于计算机进行库容曲线的分析和应用处理。

关键词：库容曲线水库调度防洪 Excel 规划求解柱蚕水库

新时代十年伟大变革中马克思人的本质学说新意蕴

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文化软实力 2024年第1期9卷 8-16页

作者：陈红邱灵海南师范大学马克思主义学院

马克思人的本质学说内在包含了人的劳动本质、需要本质和社会关系本质,这一学说在新时代十年的伟大变革中展现出新的时代意蕴。新时代十年的伟大变革,为人的劳动的发展创造了新的条件,也使劳动的主体性、创造性愈加彰显;人的需要实现了... 详细信息

马克思人的本质学说内在包含了人的劳动本质、需要本质和社会关系本质,这一学说在新时代十年的伟大变革中展现出新的时代意蕴。新时代十年的伟大变革,为人的劳动的发展创造了新的条件,也使劳动的主体性、创造性愈加彰显;人的需要实现了新的跨越和多元化发展。伴随世界多极化和经济全球化的进展,人的社会关系得以日益多样化,并向境外、域外扩展。新时代新征程进一步推进人的本质发展,必须始终坚持以人民为中心的发展思想,着力推动经济高质量发展、不断提高劳动者素质、推进收入分配制度改革,为人的劳动本质的实现创造新的条件;多措并举满足人民的生存需要、享受和发展需要,推进人的需要本质进一步发展;加强生态文明建设,构建社会主义和谐社会和人类命运共同体,促进人与自然和人与人关系的和谐发展。

关键词：人的本质劳动本质需要本质社会关系本质新时代十年伟大变革

高效液相色谱法测定鸡蛋中25种咪唑类兽药及其代谢物残留

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分析测试学报 2024年第7期43卷 1018-1024页

作者：邱月余秋玲谭超兰陆嘉莉杨倩重庆市计量质量检测研究院重庆401123

建立了高效液相色谱(HPLC)测定鸡蛋中25种咪唑类兽药及其代谢物残留的分析方法。鸡蛋液经乙腈提取并浓缩后,采用Oasis PRIME HLB固相萃取柱净化,以甲醇和水为流动相进行梯度洗脱,采用ZORBAX SB-Aq(250 mm×4.6 mm,5μm)色谱柱分离,二极... 详细信息

建立了高效液相色谱(HPLC)测定鸡蛋中25种咪唑类兽药及其代谢物残留的分析方法。鸡蛋液经乙腈提取并浓缩后,采用Oasis PRIME HLB固相萃取柱净化,以甲醇和水为流动相进行梯度洗脱,采用ZORBAX SB-Aq(250 mm×4.6 mm,5μm)色谱柱分离,二极管阵列检测器(DAD)检测,外标法定量。实验结果表明,25种目标化合物在各自质量浓度范围内线性关系良好,相关系数(r2)均大于0.999,检出限(LOD)和定量下限(LOQ)分别为0.8~5.0μg/kg和2.5~12.5μg/kg。在低、中、高3个浓度水平下进行加标回收实验,平均加标回收率为78.5%~103%,相对标准偏差(RSD)为1.1%~6.5%。该方法无明显基质效应、准确度高、精密度好,可用于鸡蛋中25种咪唑类兽药及其代谢物的日常检测。

关键词：苯并咪唑硝基咪唑代谢物高效液相色谱法鸡蛋

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Comprehensive Assessment and Promotion Policy of Producer Services' Competitiveness in Beijing City:A Comparative Analysis among Beijing,Tianjin,Shanghai,Guangzhou and Shenzhen

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Chinese Journal of Population,Resources and Environment 2011年第4期9卷 82-89页

作者： qiu ling Fang Chuanglin Shen Yuming Liu Xiaoli Institution of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Institute of Industrial and Technological Economics National Development and Reform Commission Beijing 100038 China College of Resources Environment and Tourism Capital Normal University Beijing 100048 China The Administration Centre of Urban-Rural Planning Ministry of House ＆ Urban Rural Development of P.R.China Beijing 100835 China

The five central cities-Beijing,Tianjin,Shanghai,Guangzhou and Shenzhen-of the three most important strategic regions in China,namely Beijing-Tianjin-Hebei metropolitan region,the Yangtze River Delta and the Pearl River Delta,are taken as a comparative analysis on urban producer services' competitiveness,especially focusing on the comparative advantages and disadvantages of producer services in Beijing.Firstly,based on an integrated indicator system including one objective hierarchy,four standard hierarchies and 35 indicator hierarchies,the study applies factor analysis model and analytic hierarchy process model reformed by entropy technology to measure the comprehensive competitiveness of producer services in the above five cities.Secondly,Beijing has comparative advantages of capital resource,industrial base,scientific research resource and market scale,since it takes the first place of the five cities in the comprehensive competitiveness of producer services,the competitiveness of industrial development,business environment and living environment,only inferior to Shanghai in the competitiveness of talent capital.Thirdly,Beijing has comparative disadvantages in the level of producer services development,urban innovation capability and living environment.Finally,five proposals are put forth to enhance the competitiveness of producer services in Beijing,namely perfecting the system of laws and statutes,supporting the development of industry association,implementing scientific development planning,introducing preferential fiscal and taxation policies and strengthening human capital reserve.

关键词：生产性服务业城市竞争力北京天津上海综合评价深圳广州

Basic Characteristics,Spatial Disparity and Its Major Influencing Factors of Service Industry in China

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Chinese Geographical Science 2009年第4期19卷 314-324页

作者： SHEN Yuming qiu ling REN Wangbing CAO Yi HU Dan SONG Yujing College of Resource Environment and Tourism Capital Normal University Beo＇ing 100048 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beo＇ing 100049 China Academy of Macroeconomic Research National Development and Reform Commission Beijing 100038 China

Based on the analysis of its basic characteristics,this article investigated the disparities of Chinese service industry among the three regions(the eastern China,the western China and the middle China) and inter-provincial disparities of that in the three regions by Theil coefficient and cluster analysis.Then,major factors influencing its spatial disparity were explored by correlation analysis and regression analysis.The conclusions could be drawn as follows.1) The development of Chinese service industry experienced three phases since the 1980s:rapid growth period,slow growth period,and recovery period.From the proportion of value-added and employment,its development was obviously on the low level.From the composition of industrial structure,traditional service sectors were dominant,but modern service sectors were lagged.Moreover,its spatial disparity was distinct.2) The level of Chinese service industry was divided into five basic regional ranks:well-developed,developed,relatively-developed,underdeveloped and undevel-oped regions.As a whole,the overall structure of spatial disparity was steady in 1990-2005.But there was notable gradient disparity in the interior structure of service industry among different provinces.Furthermore,the overall disparity expanded rapidly in 1990-2005.The inter-provincial disparity of service industry in the three regions,especially in the eastern China,was bigger than the disparity among the three regions.And 3) the level of economic development,the level of urban development,the scale of market capacity,the level of transportation and telecommunication,and the abundance of human resources were major factors influencing the development of Chinese service industry.

关键词：中国东部空间差异影响因素服务业特征水平划分经济发展水平城市发展水平

Syntheses of haptens and hapten-protein conjugates for insecticide propoxur and cyhalothrin

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Science China Chemistry 2010年第5期53卷 1107-1112页

作者： Sang, GuangMing Luo, ShiNeng Lin, JianGuo qiu, ling Chen, ChuanQing Yang, HaiLin Xia, YongMei Key Laboratory of Nuclear Medicine Ministry of Health Jiangsu Institute of Nuclear Medicine Wuxi 214063 China School of Chemical and Material Engineering Jiangnan University Wuxi 214122 China Key Laboratory of Industrial Biotechnology Jiangnan University Wuxi 214122 China

A facile procedure was described for the hapten design of the N-methylcarbamate insecticide propoxur.Two new haptens of propoxur(hapten 1a and hapten 1b) were synthesized by introducing appropriate spacers in the pesticide aromatic moiety of the analyte molecular structure.First,the propoxur reacted with nitric acid to yield the intermediate product.Then hapten 1a was prepared via the reduction of the intermediate product,and hapten 1b was formed by the acylation of hapten 1a with succinic anhydride.In addition,we have also developed a simple method to prepare hapten 2 for the pyrethroid insecticide cyhalothrin,which only requires two steps including the reactions of nitration and reduction.Three haptens were coupled to carrier proteins to prepare the corresponding artificial antigens.The molecular structures of these three haptens were identified by 1H NMR and MS,and those of the artificial antigens were confirmed by UV-vis.

关键词： hapten design insecticide synthesis artificial antigen