检索结果-南通市图书馆

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

不对称催化构建轴手性化合物的研究进展

辽宁化工 2024年第5期53卷 765-767页

作者：马秀娟时茜温州大学化学与材料工程学院浙江温州325035

多数具有重要生理活性的天然产物和手性药物分子中都含具有轴手性骨架,研究如何构建具有轴手性化合物并将其应用于手性药物及天然产物的高效合成具有十分重大的实际意义。对联芳基、杂联芳基以及其他类型的轴手性化合物的研究进展进行... 详细信息

多数具有重要生理活性的天然产物和手性药物分子中都含具有轴手性骨架,研究如何构建具有轴手性化合物并将其应用于手性药物及天然产物的高效合成具有十分重大的实际意义。对联芳基、杂联芳基以及其他类型的轴手性化合物的研究进展进行了讨论,并对轴手性化合物的不对称催化合成策略作了重点介绍,同时举例说明所得轴手性化合物的潜在应用价值。

关键词：轴手性化合物不对称催化合成方法

维普期刊数据库博看期刊

LNG接收站工程脚手架施工安全管理要点分析

在线全文

学校读者我要写书评

暂无评论

化工管理 2024年第3期 131-133,163页

作者：李明宇马秀娟马媛海洋石油工程股份有限公司天津300452

随着天然气市场的需求增大,LNG接收站新扩建项目逐渐增多,市场的突然扩充,导致安全管理压力剧增,同时LNG工程项目兼具传统土建建筑施工安全风险和LNG工程新型风险两大因素,管理难度大,而脚手架施工是工程中最常见的施工手段之一,其在施... 详细信息

随着天然气市场的需求增大,LNG接收站新扩建项目逐渐增多,市场的突然扩充,导致安全管理压力剧增,同时LNG工程项目兼具传统土建建筑施工安全风险和LNG工程新型风险两大因素,管理难度大,而脚手架施工是工程中最常见的施工手段之一,其在施工中安全风险较高,是整个项目安全管理的关键之处。

关键词： LNG工程脚手架安全管理

在线全文

学校读者我要写书评

暂无评论

基于碳手印方法的工业过程降碳改造研究

浙江电力 2024年第3期43卷 122-129页

作者：赵宏飞马秀娟马添翼柳双翠林小杰徐家豪黄曦浙江大学能源工程学院杭州310027 浙江华电器材检测研究院有限公司杭州310015 长春市地震速测速报中心长春130012 东方电气集团东方电机有限公司四川德阳618000

为解决工业过程碳排放降碳方法及标准不明确的问题,需要定量评价碳排放影响以制定科学的碳减排计划。传统的工业过程降碳改造局限于厂内的能源替代、设备改造等措施,因此提出一种用于描述产品全生命周期内对气候积极影响的碳手印方法,... 详细信息

为解决工业过程碳排放降碳方法及标准不明确的问题,需要定量评价碳排放影响以制定科学的碳减排计划。传统的工业过程降碳改造局限于厂内的能源替代、设备改造等措施,因此提出一种用于描述产品全生命周期内对气候积极影响的碳手印方法,结合碳足迹构建了更加全面的评价体系。以某企业工业过程中制造的水轮发电机配套水发定子线圈为研究对象,考虑边界内外多种降碳改造方案,进行了边界划分、碳足迹核算和碳手印分析,计算不同方案所产生的效率增量、寿命增量及碳手印。结果显示替换绝缘材料方案效果最为显著,碳手印方法为案例企业的降碳改造提供了有效指导。

关键词：碳手印碳足迹工业过程降碳改造

Molecular Generation and Optimization of Molecular Properties Using a Transformer Model

在线全文

学校读者我要写书评

暂无评论

Big Data Mining and Analytics 2024年第1期7卷 142-155页

作者： Zhongyin Xu xiujuan Lei Mei ma Yi Pan School of Computer Science Shaanxi Normal UniversityXi'an 710119China Faculty of Computer Science and Control Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Generating novel molecules to satisfy specific properties is a challenging task in modern drug discovery,which requires the optimization of a specific objective based on satisfying chemical ***,we aim to optimize the properties of a specific molecule to satisfy the specific properties of the generated *** matched Molecular Pairs(MMPs),which contain the source and target molecules,are used herein,and logD and solubility are selected as the optimization *** main innovative work lies in the calculation related to a specific transformer from the perspective of a matrix *** intervals and state changes are then used to encode logD and solubility for subsequent *** the experiments,we screen the data based on the proportion of heavy atoms to all atoms in the groups and select 12365,1503,and 1570 MMPs as the training,validation,and test sets,*** models are compared with the baseline models with respect to their abilities to generate molecules with specific *** show that the transformer model can accurately optimize the source molecules to satisfy specific properties.

关键词： molecular optimization transformer matched Molecular Pairs(MMPs) logD solubility

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中华优秀传统文化融入初中化学教学的研究

基础教育研究 2024年第6期 39-42页

作者：周淑晶刘龙雪马秀娟王新月佳木斯大学药学院佳木斯154007

中华优秀传统文化是中华民族最深厚的文化基石,在化学教学中主要体现为中国化学史、文学典籍、古字、成语、诗句、传统思想文化等方面。在初中化学中融入中华优秀传统文化要遵循典型性、化学性、适度性原则,同时要进行创造性运用,可巧... 详细信息

中华优秀传统文化是中华民族最深厚的文化基石,在化学教学中主要体现为中国化学史、文学典籍、古字、成语、诗句、传统思想文化等方面。在初中化学中融入中华优秀传统文化要遵循典型性、化学性、适度性原则,同时要进行创造性运用,可巧妙创设传统文化情境促进学生的高阶思维,挖掘优秀传统文化思政元素,从而促进学生的化学学习,培养学生的品质素养。

关键词：中华优秀传统文化初中化学高阶思维思政元素

维普期刊数据库博看期刊

How commercial involvement affects open source projects:three case studies on issue reporting

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2013年第8期56卷 153-165页

作者： ma xiujuan ZHOU MingHui RIEHLE Dirk School of Electronics Engineering and Computer Science Peking University Key Laboratory of High Confidence Software Technologies Ministry of Education Friedrich-Alexander-University of Erlangen-Nurnberg

Whereas most research on Internetware has focused on new technologies for keeping track of a changing Internet,little attention has been paid to the software development process.A large portion of the software running the Internet is open source *** source software is developed both by volunteers and commercial companies,often *** get involved in open source projects for commercial reasons,and bring with them a commercial software development ***,it is important to understand how commercial involvement affects the software development process of open source *** article presents case studies of three open source application servers that are being developed jointly by a volunteer community and one primary software *** are interested in better understanding developer behavior,specifically task distribution and performance,based on whether the developer is an external contributor,e.g.,a volunteer working in their spare time,or a commercial developer from inside the primary backing company who is being paid for their *** achieve this,we look at issue reporting as an example of commercial involvement in open source *** particular,we investigate the distribution of tasks among volunteers and commercial developers by studying the source of reported issues and quantify the task performance on user experience via the issue resolution *** construct measures based on historical records in issue tracking *** results show that,with intensified commercial involvement,the majority of issue reporting tasks would be undertaken by commercial developers,and issue resolution time would be reduced,implying a better user *** hope our methods and results provide practical insights for designing an efficient hybrid development process in the Internetware environment.

关键词： open source software development commercial involvement hybrid development contributor participation issue reporting

Quantitative estimation of global mean precipitation throughout the Phanerozoic era

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China Earth Sciences 2024年第5期67卷 1616-1624页

作者： xiujuan BAO Yongyun HU Laboratory for Climate and Ocean-Atmospheric Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100871China

Quantitatively estimating the global mean precipitation(GMP)throughout Earth's history is crucial for enhancing our understanding of long-term climate evolution and the hydrological ***,currently there is no established methodology for estimating global mean ***,we present the first study that estimates GMP in the Phanerozoic *** relationship between GMP and global mean surface temperature(GMST)is investigated by analyzing data from 23 models in the Coupled Model Intercomparison Project phase 6(CMIP6).The result reveals consistent and significant impact of temperature on precipitation,with a sensitivity range of 2–3%K^(-1).Additionally,we propose a method for accessing latitudinal variations in precipitation caused by land area distributions and paleo-Koppen climatic *** climatic belts are determined based on geological indicators such as coals,evaporites,and glacial *** GMP is thus quantitatively estimated by combining variations in GMST,land area distributions,and paleo-koppen climatic belts,spanning from 540 ma to the present *** quantitative GMP curve demonstrates fluctuations in GMP about 500 mm yr^(-1),with values ranging from 948 to1442 mm yr-1over the Phanerozoic *** curve aligns closely with findings derived from numerical *** presented paleoprecipitation variations facilitate a more comprehensive understanding of the interconnected geological and paleoclimatic developments.

关键词： Paleoprecipitation Paleoclimate K?ppen climatic belts Global mean precipitation Hydrological cycle

Synergic catalytic effect of Ti hydride and Nb nanoparticles for improving hydrogenation and dehydrogenation kinetics of Mg-based nanocomposite

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:materials International 2017年第1期27卷 99-104页

作者： xiujuan ma Xiubo Xie Peng Liu Li Xu Tong Liu Key Laboratory of Aerospace materials and Performance (Ministry of Education) School of Materials Science and Engineering Beihang University State Grid Smart Grid Research Institute Future Science and Technology City Changping

The Mg-9.3 wt%(TiH;-TiH)-0.7 wt% Nb nanocomposite has been synthesized by hydrogen plasma-metal reaction（HPMR） approach to enhance the hydrogen sorption kinetics of Mg at moderate temperatures by providing nanosizing effect of increasing H "diffusion channels" and adding transition metallic catalysts. The Mg nanoparticles（NPs） were in hexagonal shape range from 50 to 350 nm and the average size of the NPs was 177 nm. The small spherical TiH;, TiH and Nb NPs of about 25 nm uniformly decorated on the surface of the big Mg NPs. The Mg-TiH;-TiH-Nb nanocomposite could quickly absorb 5.6 wt% H;within 5 min at 573 K and 4.5 wt% H;within 5 min at 523 K, whereas the pure Mg prepared by HPMR could only absorb 4 and 1.5 wt% H;at the same temperatures. TiH;, TiH and Nb NPs transformed into TiH;and Nb H during hydrogenation and recovered after dehydrogenation process. The apparent activation energies of the nanocomposite for hydrogenation and dehydrogenation were 45.0 and 50.7 kJ mol;, which are much smaller than those of pure Mg NPs, 123.8 and 127.7 kJ mol;. The improved sorption kinetics of the Mg-based nanocomposite at moderate temperatures and the small activation energy can be interpreted by the nanostructure of Mg and the synergic catalytic effects of Ti hydrides and Nb NPs.

关键词： magnesium Nanocomposite Catalytic effect Hydrogen storage

Achieving Negatively Charged Pt Single Atoms on Amorphous Ni(OH)_(2)Nanosheets with Promoted Hydrogen Absorption in Hydrogen Evolution

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Nano-Micro Letters 2024年第10期16卷 213-224页

作者： Yue Liu Gui Liu Xiangyu Chen Chuang Xue Mingke Sun Yifei Liu Jianxin Kang xiujuan Sun Lin Guo School of Chemistry Beijing Advanced Innovation Center for Biomedical EngineeringKey Laboratory of Bio-inspired Smart Interfacial Science and TechnologyBeihang UniversityBeijing 100191People's Republic of China School of Chemistry Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of EducationXiangtan UniversityXiangtan 411105HunanPeople'Republic of China

Single-atom(SA)catalysts with nearly 100%atom utilization have been widely employed in electrolysis for decades,due to the outperforming catalytic activity and ***,most of the reported SA catalysts are fixed through the strong bonding between the dispersed single metallic atoms with nonmetallic atoms of the substrates,which greatly limits the controllable regulation of electrocatalytic activity of SA *** this work,Pt-Ni bonded Pt SA catalyst with adjustable electronic states was successfully constructed through a controllable electrochemical reduction on the coordination unsaturated amorphous Ni(OH)_(2)nanosheet *** on the X-ray absorption fine structure analysis and first-principles calculations,Pt SA was bonded with Ni sites of amorphous Ni(OH)_(2),rather than conventional O sites,resulting in negatively charged Pt^(δ-).In situ Raman spectroscopy revealed that the changed configuration and electronic states greatly enhanced absorbability for activated hydrogen atoms,which were the essential intermediate for alkaline hydrogen evolution *** hydrogen spillover process was revealed from amorphous Ni(OH)_(2)that effectively cleave the H-O-H bond of H_(2)O and produce H atom to the Pt SA sites,leading to a low overpotential of 48 mV in alkaline electrolyte at-1000 ma cm^(-2)mg^(-1)_(Pt),evidently better than commercial Pt/C *** work provided new strategy for the control-lable modulation of the local structure of SA catalysts and the systematic regulation of the electronic states.

关键词： Hydrogen evolution reaction Amorphous Pt single atoms Hydrogen spillover