检索结果-南通市图书馆

Discovery of a new family member of arsenic–vanadium polyoxometalates with high catalytic performance for one-pot coupling of CO2, epoxides and amines

在线全文

学校读者我要写书评

暂无评论

Tungsten 2025年第1期7卷 80-87页

作者： Fang-Qian Wang Yin Zhang wei-wei Wang Mei-Qian Fu Hong-Bing Mo wei-Dong Yu Chao Liu Jun Yan College of Chemistry and Chemical Engineering Central South University Junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[N（CH3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.Furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mechanism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

关键词： Arsenic CO2 conversion Oxazolidinone Polyoxometalates Vanadium

Solar cycles during the seventeenth century revealed by equatorial aurora records

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Earth and Planetary Physics 2025年第1期9卷 182-187页

作者： Yong wei LiMei Yan Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Solar cycles are fundamental to astrophysics,space exploration,technological infrastructure,and Earth's climate.A better understanding of these cycles and their history can aid in risk mitigation on Earth,while also deepening our knowledge of stellar physics and solar system *** the solar cycles between 1600 and 1700-especially the post-1645 Maunder Minimum,characterized by significantly reduced solar activity-poses challenges to existing solar activity *** study utilizes a new red equatorial auroral catalog from ancient Korean texts to establish solar cycle patterns from 1623 to ***,a further reevaluation of the solar cycles between 1610 and 1755 identified a total of 13 cycles,diverging from the widely accepted record of 12 cycles during that *** research enhances our understanding of historical solar activity,and underscores the importance of integrating diverse historical sources into modern analyses.

关键词： solar cycle Maunder Minimum solar activity red equatorial aurora West Pacific geomagnetic anomaly

From text to image:challenges in integrating vision into ChatGPT for medical image interpretation

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第2期20卷 487-488页

作者： Shunsuke Koga wei Du Department of Pathology and Laboratory Medicine Hospital of the University of PennsylvaniaPhiladelphiaPAUSA

Large language models(LLMs),such as ChatGPT developed by OpenAI,represent a significant advancement in artificial intelligence(AI),designed to understand,generate,and interpret human language by analyzing extensive text *** potential integration into clinical settings offers a promising avenue that could transform clinical diagnosis and decision-making processes in the future(Thirunavukarasu et al.,2023).This article aims to provide an in-depth analysis of LLMs’current and potential impact on clinical *** ability to generate differential diagnosis lists underscores their potential as invaluable tools in medical practice and education(Hirosawa et al.,2023;Koga et al.,2023).

关键词： image diagnosis text

蔗糖浓度及ICSI前培养时间对人卵母细胞慢速冷冻影响的初步研究

在线全文

学校读者我要写书评

暂无评论

生殖与避孕 2007年第9期27卷 585-588页

作者：李莉丛林曹云霞章志国魏兆莲周平赵济华李芬安徽医科大学第一附属医院生殖中心合肥230022

目的:研究2种蔗糖浓度对人类卵母细胞冻融结果的影响。方法:采用慢冻-快融程序化冷冻方法冻融不同时期的人卵母细胞,根据冷冻液中蔗糖浓度不同分为二组(A组:0.2mol/L蔗糖组;B组:0.3mol/L蔗糖组),比较其复苏后存活情况。B组复苏后成熟卵... 详细信息

目的:研究2种蔗糖浓度对人类卵母细胞冻融结果的影响。方法:采用慢冻-快融程序化冷冻方法冻融不同时期的人卵母细胞,根据冷冻液中蔗糖浓度不同分为二组(A组:0.2mol/L蔗糖组;B组:0.3mol/L蔗糖组),比较其复苏后存活情况。B组复苏后成熟卵母细胞培养不同的时间行单精子卵胞浆内注射(ICSI),分析培养时间对卵母细胞受精和发育结果的影响。结果:相对于A组的冷冻方法,B组明显提高了未成熟卵母细胞和成熟卵母细胞的存活率(72.0% vs 54.4%,68.8% vs 44.4%),二组卵母细胞复苏后形态异常率无明显差异;复苏后存活的成熟卵母细胞ICSI前培养3-4h后受精率、优质胚胎率、囊胚形成率明显高于培养1h、2h和5h。结论:适当提高蔗糖浓度更有利于各时期卵母细胞的冻存,复苏的成熟卵母细胞培养3-4h有助于卵母细胞结构的恢复,提高正常受精率和后期发育潜能。

关键词：卵母细胞慢速冷冻蔗糖浓度培养时间

Record-breaking bifunctional oxygen electrocatalyst accomplished by a data-driven approach for zinc-air batteries

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2025年第1期100卷 144-145页

作者： Deviprasath Chinnadurai Zhi wei Seh Institute of Materials Research and Engineering (IMRE) Agency for Science Technology and Research (A*STAR)

Rechargeable zinc-air batteries(ZABs) have recently drawn great attention in energy research due to their high theoretical capacity,low costs, and inherently safe nature [1–3]. However, the sluggish cathode reactions necessitate the development of bifunctional oxygen electrocatalysts with lower ΔE indicator values. The ΔE indicator is commonly employed to quantitatively evaluate the electrocatalytic activity of a bifunctional oxygen electrocatalyst,representing the overall overpotential from oxygen reduction reaction(ORR) to oxygen evolution reaction(OER).

关键词：

Fabrication and Mechano-sensing Characteristics of Bending Polypyrrole Actuator

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 240-245页

作者： CHEN Jinyou HU wei School of Automotive Engineering Hunan Financial&Industrial Vocational-technical CollegeHengyang 421002China College of Mechanical and Electrical Engineering Hunan Agricultural UniversityChangsha 410128China

To prepare a conductive polymer actuator with decent performance,a self-built experimental platform for the preparation of polypyrrole film is *** of the essential goals is to examine the mechanical characteristics of the actuator in the presence of various combinations of process parameters,combined with the orthogonal test method of"four factors and three levels".The bending and sensing characteristics of actuators of various sizes are methodically examined using a self-made bending polypyrrole *** functional relationship between the bending displacement and the output voltage signal is established by studying the characteristics of the actuator sensor subjected to various degrees of *** experimental results reveal that the bending displacement of the actuator tip almost exhibits a linear variation as a function of length and *** the voltage reaches 0.8 V,the bending speed of the actuator tends to be ***,the mechanical properties of the self-assembled polypyrrole actuator are verified by the design and fabrication of the microgripper.

关键词： conductive polymer polypyrrole mechanical characteristics actuators sensing characteristics

A self-adaptive inorganic in-situ separator by particle crosslinking for nonflammable lithium-ion batteries

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2025年第1期100卷 469-480页

作者： Jiarui Yang Jiuzhou Liu Wenrui Cai Ziyu zhao Shan Wang Lu He Shanshan Lv Zhiwei Zhu Zhongfeng Ji Guojiang Wen Hua Li Yuanming Zhai Xuewei Fu wei Yang Yu Wang College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering Sichuan University

All-safe liquid-state lithium-ion batteries(ASLS-LIBs) is of great interest as they can potentially combine the safety of all-solid-state batteries with the high performance and low manufacturing cost of traditional liquid-state LIBs. However, the practical success of ASLS-LIBs is bottlenecked by the lack of advanced separator technology that can simultaneously realize high performances in puncturing-tolerability,fire-resistance, and importantly, wetting-capability with non-flammable liquid-electrolytes. Here, we propose a concept of inorganic in-situ separator(IISS) by hybrid-sol physical crosslinking directly onto the electrode surface to address the above challenges. Particularly, the hybrid-sol is designed with silica nanoparticles as the building block and poly(vinylidene difluoride) nanoparticles as the crosslinking agent. The critical factors for controlling the IISS microstructures and properties have been systematically investigated. The advantages of the IISS have been confirmed by its fast wetting with various fireresistant liquid-electrolytes, customizable thickness and porous structures, robust interface with planar or three-dimensional(3D)-structured electrodes, and importantly, unexpected self-adaptability against puncturing. Enabled by the above merits, a fire-resistant ASLS-LIB is successfully assembled and demonstrated with stable electrochemical performance. This sol-crosslinked IISS may open an avenue for the studies on the next-generation separator technology, cell assembling, solid electrolyte processing as well as non-flammable secondary batteries.

关键词： Silica nanoparticles

Dative B–N bonds weaven toward two-dimensional purely organic materials for single crystals

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 Chemistry 2025年第1期68卷 12-14页

作者： wei-Lei Zhou Siwei Wang Yong Chen College of Chemistry and Materials Science Inner Mongolia Key Laboratory of Chemistry for Nature Products and Synthesis for Functional Molecules Innovation Team of Optical Functional Molecular Devices Inner Mongolia Minzu University College of Chemistry Nankai University

Molecular topology is one of the important topics to study and understand the relationship between molecular structure and properties [1]. Particularly, two-dimensional (2D) materials with extremely high surface area and ultra-thin morphology have attracted considerable attention due to their unexpected properties in materials and chemistry [2,3].

关键词：

Applications of in-situ solid-state nuclear magnetic resonance in methanol to olefins reaction

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 Chemistry 2025年第1期68卷 134-151页

作者： Jing Niu Shutao Xu Yingxu wei Zhongmin Liu National Engineering Research Center of Lower-Carbon Catalysis Technology Dalian Institute of Chemical PhysicsChinese Academy of Sciences State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

The methanol-to-olefins（MTO） reaction offers an alternative pathway for the production of low-carbon olefins from non-oil feedstocks. Fundamental research has been impeded by a lack of comprehensive understanding of its underlying mechanism,despite the significant progress made in industry. In-situ solid-state nuclear magnetic resonance（ss NMR） spectroscopy has emerged as a pivotal tool, offering crucial insights into key species under real-time operando conditions. Furthermore, the host–guest interaction between zeolites or surface species residing on zeolites and the reactant/active intermediates is revealed by the combination of in-situ13C MAS NMR and 2D correlation spectroscopy. Moreover, recent technological advancements in hyperpolarization（HP） methods, including HP129Xe NMR and dynamic nuclear polarization（DNP）, have significantly improved the sensitivity of ss NMR, enabling detailed structural and kinetic analysis as well as the detection of trace species. In this feature article, we summarized recent advancements in（in-situ） ss NMR spectroscopy applied to MTO reaction processes,encompassing mechanistic investigations at various stages and the intricate host–guest interactions. These theoretical insights into the dynamic evolution of MTO reactions lay a solid foundation for the optimization of catalytic processes and the development of efficient catalysts, thereby advancing the techniques towards more sustainable and economical production route for olefins.

关键词： MTO zeolites in-situ ssNMR reactive intermediates reaction mechanism