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二元包合水合物储氢及促进剂作用的理论研究

高等学校化学学报 2024年第1期45卷 119-128页

作者：张宏淑梁攀薛颖颖韦瑶瑶陕西学前师范学院化学化工学院西安710100 陕西师范大学化学化工学院西安710119 临沂大学化学化工学院临沂276000

尽管包合水合物因其高储能密度和环境友好等优点,可以作为大规模工业化应用的潜在储氢材料,但在理解包合水合物中氢气的结构和扩散方面尚存在较大争议.本文应用密度泛函理论(DFT)探讨了sI型包合水合物的储氢结构和性质.结果表明,纯氢气... 详细信息

尽管包合水合物因其高储能密度和环境友好等优点,可以作为大规模工业化应用的潜在储氢材料,但在理解包合水合物中氢气的结构和扩散方面尚存在较大争议.本文应用密度泛函理论(DFT)探讨了sI型包合水合物的储氢结构和性质.结果表明,纯氢气水合物中512笼中可容纳2个H_(2)分子,CH_(4)和C_(2)H_(6)促进剂对其结构和性质没有明显影响;而在N_(2)和CO_(2)促进剂作用下512笼可容纳的H_(2)分子增加到3个,氢气水合物稳定性得到提高,主客体间的静电和氢键相互作用增强且H—H伸缩振动峰值蓝移.当N_(2)和CO_(2)包合物512笼中氢气的占据达3个H2分子时,1个H_(2)分子通过五边形面的扩散能垒接近于纯氢气水合物中的2倍,有效阻碍了氢气在笼间的扩散.

关键词：包合水合物储氢稳定性扩散促进剂作用

Storage, form, and influencing factors of karst inorganic carbon in a carbonate area in China

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Science China Earth Sciences 2024年第3期67卷 725-739页

作者： Chaochao DU Xiaoyong BAI Yangbing LI Qiu TAN Cuiwei ZHAO Guangjie LUO Luhua WU Fei CHEN Chaojun LI Chen RAN Sirui ZHANG Lian XIONG Fengjiao SONG Biqin XIAO Zilin LI yingying xue Mingkang LONG Qing LUO Xiaoyun ZHANG Minghui LI Xiaoqian SHEN Shu YANG State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China School of Geography and Environmental Sciences Guizhou Normal UniversityGuiyang 550001China CAS Center for Excellence in Quaternary Science and Global Change Xi'an 710061China Guizhou Provincial Key Laboratory of Geographic State Monitoring of Watershed Guizhou Normal CollegeGuiyang 550018China College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China

Carbonate rock chemical weathering carbon sinks reduce the rate of increase of the atmospheric CO_(2) concentration and global warming. However, uncertainty still exists in the estimation results of carbonate rock chemical weathering carbon sink fluxes(CCSF), and the contributions of climate change and ecological restoration to the CCSF are not clear. To this end, we compiled published site data on ion concentrations in different watersheds in China and used a classical thermodynamic dissolution model to reassess the potential and spatial and temporal patterns of the CCSF in China from 1991 to 2020. We quantified the contributions of temperature(MAT), precipitation(MAP), evapotranspiration(ET), soil water(SM), and the normalized difference vegetation index(NDVI) to the CCSF. The results revealed that(1) China's CCSF was 22.76 t CO_(2)km^(-2)yr^(-1), which was higher than the global average(15.77 t CO_(2)km^(-2)yr^(-1)). The total carbonate rock chemical weathering carbon sink(CCS) was 4772.67×10^(4)t CO_(2), contributing 14.91% of the global CCS through a carbonate rock area of 252.98×10^(4)km^(-2).(2) China's CCSF decreased gradually from southeast to northwest, with values of 33.14, 12.93, and7.27 t CO_(2)km^(-2)yr^(-1)in the southern karst, Qinghai-Tibetan karst, and northern karst regions, respectively.(3) The overall CCSF in China exhibited an increasing trend from 1991 to 2020, with a rate of increase of 0.16 t CO_(2)km^(-2)yr^(-1).(4) The contributions of the MAP, MAT, ET, SM, and NDVI to the CCSF were 63.3%, 3.02%, 27.5%, 3.1%, and 3.05%, respectively. Among them, the increase in precipitation was the main contributor to the increase in the CCSF in China over the last 30 years, while the enhancement of ET offset part of the positive contribution of the increase in precipitation to the CCSF. In conclusion, the results of this study provide a systematic quantification of the magnitude, the patterns, and the influencing factors of CCS over a long time series in

关键词： Carbonate rocks Carbon sinks Patterns Influencing factors Thermodynamic dissolution modeling

Study of the Single Shear Performance of a Joint with a New Beech and Self-Tapping Screw Composite Dowel

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Journal of Renewable Materials 2022年第2期10卷 401-413页

作者： Xudong Zhu yingying xue xuewen Zhang Pengfei Qi Jie Shen Changtong Mei College of Materials Science and Engineering Nanjing Forestry UniversityNanjing210037China College of Civil Engineering Yangzhou Polytechnic InstituteYangzhou225127China College of Architectural Science and Engineering Yangzhou UniversityYangzhou225127China

A new beech and self-tapping screw composite dowel is proposed and studied,its performance being compared with that of beech dowels and self-tapping screws *** single shear performance of components connected by composite dowels was *** show that the dowels are a good choice for components requiring high *** remain a good choice for components requiring excellent seismic *** group presents similar maximum load stiffness to those of composite dowels,but other ductility parameters are superior for composite *** best connection mode was provided by two composite *** on connecting two points,structural elements with two composite dowels showed much better load bearing ability than when joined by two beech dowels or by two self-tapping screws *** structural element with two composite dowels not only presented better initial stiffness,but also exhibited a better ductility coeffi-cient and less energy ***,the composite dowels can be used for beam column connection,dowel laminated timber,and restoration or enhancement of ancient buildings.

关键词： Composite dowel beech dowel self-tapping screw single shear performance

Ratiometric Fluorescent Probe Based on Novel Red-emission BODIPY for Determination of Bovine Serum Albumin

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Chemical Research in Chinese Universities 2014年第5期30卷 738-742页

作者： SONG Fengling xue yingying WANG Xu WANG Jingyun XIONG Xiaoqing PENG Xiaojun State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116024 P. R. China

A novel red-emission boron-dipyrromethene（BODIPY） dye with a pyrrole ring was synthesized simply via one-pot reaction. The spectral properties of it were investigated under the conditions of different solvents. The results show that the as-prepared BODIPY dye is extremely sensitive to solvent polarity, and the fluorescent emission enhances with the decrease of solvent polarity. In aqueous buffer, the addition of bovine serum albumin leads to a ratiometric change in absorption spectra with an association constant of 1.16×10^6 L/mol. Meanwhile, the fluorescence emission increases greatly at 622 nm but changes slightly at 575 nm. The response time is very short（less than 3 min）, and the changes of color can be noticed by naked eyes. Bovine serum albumin can be detected by this ratiometric fluorescence probe, but other proteins or enzymes cannot be detected by this method, which indicates that this novel dye has high selectivity towards bovine serum albumin. The reason is that bovine serum albumin has suitable hydro- phobic cavities for binding with the dye. In addition, the dye molecule can penetrate cell membrane easily and make a fast fluorescent stain, which makes it a potential probe for living-cell fluorescence imaging.

关键词： Fluorescent dye Boron-dipyrromethene(BODIPY) Bovine serum albumin Ratiometric High selectivity

中国西南喀斯特石漠化治理对生物多样性的影响

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地理学报 2024年第1期79卷 97-113页

作者：龙明康白晓永李姿霖薛盈盈陈飞李朝君冉晨张思蕊杜朝超宋丰姣肖碧琴熊练中国科学院地球化学研究所环境地球化学国家重点实验室贵阳550081 中国科学院大学北京100049 贵州大学资源与环境工程学院贵阳550025 重庆大学环境与生态学院重庆400044 贵州师范大学地理与环境科学学院贵阳550001 贵州省水利科学院贵阳550002

生态修复措施会对生物多样性热点区域产生强烈影响,因此量化石漠化治理对生物多样性的贡献在西南喀斯特地区是至关重要的。本文通过回归分析以及残差趋势分析等方法,揭示了2000—2020年中国西南喀斯特地区石漠化及生物多样性的时空演变... 详细信息

生态修复措施会对生物多样性热点区域产生强烈影响,因此量化石漠化治理对生物多样性的贡献在西南喀斯特地区是至关重要的。本文通过回归分析以及残差趋势分析等方法,揭示了2000—2020年中国西南喀斯特地区石漠化及生物多样性的时空演变规律,量化了石漠化治理等因素对生物多样性的贡献。结果表明:中国西南喀斯特地区石漠化以轻度石漠化和中度石漠化为主,石漠化总面积减少了10.25万km^(2),减少速率为0.49万km^(2)/a;喀斯特地区生物多样性总体呈增加趋势,生物多样性综合指数均值为0.40,总体维持在中等水平;石漠化治理和生物多样性呈正相关关系,其对生物多样性的贡献为26.39%;气候变化和人类活动对生物多样性的贡献分别为52.78%、47.22%。结果表明,石漠化治理对生物多样性表现出积极贡献,对后续生态修复工程的实施以及生物多样性的保护具有一定指导意义。

关键词：中国西南石漠化治理气候变化生物多样性

Fine-tuning of pore-space-partitioned metal-organic frameworks for efficient C_(2)H_(2)/C_(2)H_(4) and C_(2)H_(2)/CO_(2) separation

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Chinese Chemical Letters 2023年第2期34卷 593-597页

作者： Xiaobing Mu yingying xue Mancheng Hu Peng Zhang Ying Wang Haipeng Li Shuni Li Quanguo Zhai Key Laboratory of Macromolecular Science of Shaanxi Province Key Laboratory of Applied Surface and Colloid ChemistryMinistry of EducationSchool of Chemistry&Chemical EngineeringShaanxi Normal UniversityXi'an 710062China

Acetylene (C_(2)H_(2)) and ethylene (C_(2)H_(4)) both are important chemical raw materials and energy fuel *** the effective removement of trace C_(2)H_(2)from C_(2)H_(4)and the purification of C_(2)H_(2)from carbon dioxide(CO_(2)) are particularly challenging in the petrochemical *** a class of porous physical adsorbent,metal-organic frameworks (MOFs) have exhibited great success in separation and purification of light hydrocarbon ***,we rationally designed four novel MOFs by the strategy of pore space partition(PSP) via introducing triangular tri(pyridin-4-yl)-amine (TPA) into the 1D hexagonal channels of acs-type parent *** modulating the functional groups of linear dicarboxylate linkers for the parent skeleton,a series of isoreticular PSP-MOFs (SNNU-278-281) were successfully *** synergistic effects of suitable pore size and Lewis basic functional groups make these MOFs ideal C_(2)H_(2)*** gas adsorption experimental results show that all MOFs have excellent C_(2)H_(2)***,SNNU-278demonstrates a high C_(2)H_(2)uptake of 149.7 cm3/g at 273 K and 1 ***,SNNU-278-281 MOFs also show extremely great C_(2)H_(2)separation from CO_(2)and C_(2)H_(4).The optimized SNNU-281 with highdensity hydroxy groups exhibits extraordinary C_(2)H_(2)/CO_(2)and C_(2)H_(2)/C_(2)H_(4)dynamic breakthrough interval times up to 31 min/g and 17 min/g under 298 K and 1 bar.

关键词： Metal-organic framework Pore space partition C_(2)H_(2)adsorption C_(2)H_(2)/C_(2)H_(4)separation C_(2)H_(2)/CO_(2)separation

Distributed Storage System for Electric Power Data Based on HBase

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Big Data Mining and Analytics 2018年第4期1卷 324-334页

作者： Jiahui Jin Aibo Song Huan Gong yingying xue Mingyang Du Fang Dong Junzhou Luo School of Computer Science and Engineering Southeast UniversityNanjing 211189China

Managing massive electric power data is a typical big data application because electric power systems generate millions or billions of status,debugging,and error records every single *** guarantee the safety and sustainability of electric power systems,massive electric power data need to be processed and analyzed quickly to make real-time *** solutions typically use relational databases to manage electric power ***,relational databases cannot efficiently process and analyze massive electric power data when the data size increases *** this paper,we show how electric power data can be managed by using HBase,a distributed database maintained by *** system consists of clients,HBase database,status monitors,data migration modules,and data fragmentation *** evaluate the performance of our system through a series of *** also show how HBase’s parameters can be tuned to improve the efficiency of our system.

关键词： electric power data HBase data storage

研发费用加计扣除、融资约束与企业成本加成——来自中国沪深A股上市公司的经验证据

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财经科学 2022年第5期 47-60页

作者：薛迎迎上海财经大学公共经济与管理学院

本文在理论剖析融资约束如何影响成本加成以及研发费用加计扣除政策如何发挥作用的基础上,基于中国2014-2019沪深两市A股上市公司样本数据进行实证检验。结果显示,融资约束对于成本加成具有显著抑制效应,而加计扣除政策的实施能够显著... 详细信息

本文在理论剖析融资约束如何影响成本加成以及研发费用加计扣除政策如何发挥作用的基础上,基于中国2014-2019沪深两市A股上市公司样本数据进行实证检验。结果显示,融资约束对于成本加成具有显著抑制效应,而加计扣除政策的实施能够显著缓解融资约束对于成本加成的抑制效应,这一结果在控制了内生性影响以及替换变量的稳健性结果中依然成立。针对企业规模、所有制类型以及产业类型的异质性分析结果表明,中小型企业、民营企业以及非制造业企业加计扣除政策发挥的调节作用更大。究其影响机制,融资约束主要经由抑制研发投入增加的渠道对成本加成产生负向影响,而加计扣除政策的实施能够正向调节融资约束对研发投入的抑制作用,进而起到缓解融资约束对成本加成的抑制效应。

关键词：研发费用加计扣除融资约束企业成本加成研发投入

Research on the mental health condition of the elderly under the institution for the aged

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International English Education Research 2018年第3期 7-10页

作者： GAO Jie CAI Guomei xue yingying School of Management of Shanghai University of Engineering Science Shanghai 201620

After entering the aging society, the pension problem of the elderly population has become an urgent problem to be solved in the current and future social life of our country. The rapid growth of the elderly population will inevitably bring about changes in the family structures, which leads to the inevitable development trend of the old-age pension institutions for the elderly. With the progress of the society, the needs of the elderly for the old-age pension are not only satisfied with their life care, but also with the spiritual needs. Based on the planning contents of the 13th Five-Year Plan for the elderly, on the basis of the Maslow＇s demand level theory, this paper analyzes the present status of the services of the institutions for the elderly to the elderly psychological health, and concludes that the needs of the emotions of the elderly, the needs of their self-esteem, the needs of their self-realization and their physiological needs of the elderly and their security needs are equally important.

关键词： Institutional endowment the elderly mental health