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One-pot synthesis of N-aryl propargylamine from aromatic boronic acid,aqueous ammonia,and propargyl bromide under microwave-assisted conditions

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Chinese Chemical Letters 2014年第5期25卷 779-782页

作者： Yu-Bo Jiang Wen-Sheng Zhang hui-ling cheng Yu-Qi Liu Rui Yang Faculty of Science Kunming University of Science and Technology School of Science and Technology Jiaozuo Teachers’ College

A facile,one-pot synthesis of N-aryl propargylamine from aromatic boronic acid,aqueous ammonia,and propargyl bromide has been achieved under microwave-assisted *** reactions can be smoothly completed within a total 10 min through a two-step procedure,including copper-catalyzed coupling of aromatic boronic acids with aqueous ammonia and following propargylation by propargyl bromide.

关键词： One-pot Microwave N-Aryl propargylamine Aromatic boronic acid Aqueous ammonia Propargyl bromide

Investigating Müller glia reprogramming in mice: a retrospective of the last decade, and a look to the future

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Neural Regeneration Research 2025年第4期20卷 946-959页

作者： Zhiyuan Yin Jiahui Kang Xuan cheng hui Gao Shujia Huo Haiwei Xu Key Lab of Visual Damage and Regeneration&Restoration of Chongqing Southwest Eye HospitalSouthwest HospitalThird Military Medical University(Army Medical University)ChongqingChina

Müller glia,as prominent glial cells within the retina,plays a significant role in maintaining retinal homeostasis in both healthy and diseased *** lower vertebrates like zebrafish,these cells assume responsibility for spontaneous retinal regeneration,wherein endogenous Müller glia undergo proliferation,transform into Müller glia-derived progenitor cells,and subsequently regenerate the entire retina with restored ***,Müller glia in the mouse and human retina exhibit limited neural reprogramming.Müller glia reprogramming is thus a promising strategy for treating neurodegenerative ocular disorders.Müller glia reprogramming in mice has been accomplished with remarkable success,through various *** in molecular,genetic,epigenetic,morphological,and physiological evaluations have made it easier to document and investigate the Müller glia programming process in ***,there remain issues that hinder improving reprogramming efficiency and ***,understanding the reprogramming mechanism is crucial toward exploring factors that will improve Müller glia reprogramming efficiency,and for developing novel Müller glia reprogramming *** review describes recent progress in relatively successful Müller glia reprogramming *** also provides a basis for developing new Müller glia reprogramming strategies in mice,including epigenetic remodeling,metabolic modulation,immune regulation,chemical small-molecules regulation,extracellular matrix remodeling,and cell-cell fusion,to achieve Müller glia reprogramming in mice.

关键词： cell fusion chemical small-molecules epigenetic extracellular matrix immune metabolic mice Müller glia neurodegenerative diseases reprogramming retina regeneration

Ideal Bi‑Based Hybrid Anode Material for Ultrafast Charging of Sodium‑Ion Batteries at Extremely Low Temperatures

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Nano-Micro Letters 2025年第3期17卷 152-167页

作者： Jie Bai Jian hui Jia Yu Wang Chun cheng Yang Qing Jiang Key Laboratory of Automobile Materials(Jilin University) Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchun 130022People’s Republic of China

Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or ***,the key capability of ultrafast charging at ultralow temperature for SIBs is rarely ***,a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue,which is synthesized via a high temperature shock *** a hybrid shows an unprecedented rate performance(237.9 mAh g^(−1)at 2 A g^(−1))at−60℃,outperforming all reported SIB anode *** with a Na_(3)V_(2)(PO_(4))_(3)cathode,the energy density of the full cell can reach to 181.9 Wh kg^(−1)at−40°*** on this work,a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current.

关键词： Bi nanoparticles High temperature shock High-rate activation Ultrafast charging Low-temperature sodium-ion batteries

新型职业农民农业生产效率的三阶段DEA分析

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华东经济管理 2018年第8期32卷 177-184页

作者：徐辉孔令成张明如长江大学湖北农村发展研究中心湖北荆州434023 长江大学经济学院湖北荆州434023

文章基于七个典型省份新型职业农民样本数据,运用三阶段DEA模型,对省域新型职业农民农业生产效率进行了实证分析。结果表明:管理因素、环境因素和随机误差对职业农民农业生产效率均具有显著影响,在三阶段DEA模型框架下对环境因素和随机... 详细信息

文章基于七个典型省份新型职业农民样本数据,运用三阶段DEA模型,对省域新型职业农民农业生产效率进行了实证分析。结果表明:管理因素、环境因素和随机误差对职业农民农业生产效率均具有显著影响,在三阶段DEA模型框架下对环境因素和随机误差进行剥离是合理的。环境因素中,农业信息服务与新型职业农民农业生产效率呈现显著的正向相关关系,新型职业农民培训、创业支持政策、资金扶持政策等与职业农民生产效率之间的关系则是复杂的。与第一阶段相比,第三阶段新型职业农民农业生产经营的综合技术效率和纯技术效率有所下降,而其规模效率则有一定幅度的提升,但纯技术效率值和规模效率值均不高。为了从整体上进一步提高新型职业农民农业生产的效率,需要强化新型职业农民培训力度,培育高素质职业农民队伍,制定土地流转法和人口流动法,加大新型职业农民扶持力度,构建农业生产利益共同体,创建农业综合信息服务平台以及推动互联网与农业深度融合。

关键词：新型职业农民农业生产效率三阶段DEA模型

Moment Redistribution Effect of the Continuous Glass Fiber Reinforced Polymer-Concrete Composite Slabs Based on Static Loading Experiment

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Structural Durability & Health Monitoring 2025年第1期19卷 105-123页

作者： Zhao-Jun Zhang Wen-Wei Wang Jing-Shui Zhen Bo-cheng Li De-cheng Cai Yang-Yang Du hui Huang Offshore Oil Engineering Co.Ltd. Tianjin300461China Department of Bridge Engineering School of TransportationSoutheast UniversityNanjing211189China

This study aimed to investigate the moment redistribution in continuous glass fiber reinforced polymer(GFRP)-concrete composite slabs caused by concrete cracking and steel bar yielding in the negative bending moment *** experimental bending moment redistribution test was conducted on continuous GFRP-concrete composite slabs,and a calculation method based on the conjugate beam method was *** composite slabs were formed by combining GFRP profiles with a concrete layer and supported on steel beams to create two-span continuous composite slab *** methods,epoxy resin bonding,and stud connection,were used to connect the composite slabs with the steel *** experimental findings showed that the specimen connected with epoxy resin exhibited two moments redistribution phenomena during the loading process:concrete cracking and steel bar yielding at the internal *** contrast,the composite slab connected with steel beams by studs exhibited only one-moment redistribution phenomenon throughout the loading *** the concrete at the internal support cracked,the bending moment decreased in the internal support section and increased in the midspan *** the steel bars yielded,the bending moment further decreased in the internal support section and increased in the mid-span *** GFRP profiles do not experience cracking,there was no significant decrease in the bending moment of the mid-span *** test specimens experienced compressive failure of concrete at the mid-span *** results showed good agreement between the calculated and experimental values of bending moments in the mid-span section and internal support *** proposed model can effectively predict the moment redistribution behavior of continuous GFRP-concrete composite slabs.

关键词： Moment redistribution GFRP-concrete composite slabs bending moment experimental study analysis model

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固相合成草甘膦钾盐

化学工程 2017年第7期45卷 56-60页

作者：桑惠玲杨阿三程榕孙勤郑燕萍浙江工业大学化学工程学院浙江省生物燃料利用技术研究重点实验室浙江杭州310014

在500 m L的搅拌反应器中,固体草甘膦和固体碳酸钾直接反应合成草甘膦钾盐。采用气相色谱法检测反应生成CO2的量,并考察了气体湿度、反应温度、物料比对该反应的影响。研究结果表明:固相含水率显著影响反应物之间的传质,该反应存在诱导... 详细信息

在500 m L的搅拌反应器中,固体草甘膦和固体碳酸钾直接反应合成草甘膦钾盐。采用气相色谱法检测反应生成CO2的量,并考察了气体湿度、反应温度、物料比对该反应的影响。研究结果表明:固相含水率显著影响反应物之间的传质,该反应存在诱导期、加速期及降速期3个阶段。通气湿度增大,固相反应物含水率升高,反应诱导期缩短,反应更易进行,相同反应时间的反应转化率和平均反应速率增大。通气湿度过高,带湿能力下降,反应加速期产生的水分会导致产物结团,影响后续反应。在相同通气条件下,反应温度升高,平均反应速率先增加后减小,存在较适宜的反应温度。温度过高会使反应体系中的水分流失加快,使固相中的含水率较低,反应速率反而下降。草甘膦与碳酸钾的摩尔比减小,相同质量的草甘膦与碳酸钾之间的接触机率增加,可以加快草甘膦的反应。

关键词：草甘膦钾盐固相法草甘膦碳酸钾

Control of Corner Separation for a Linear Compressor Cascade via Bionic Slanting Riblets at the Endwall

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Journal of Thermal Science 2025年第1期34卷 129-144页

作者： ZHANG Peng LI Yonghong cheng Rixin Key Laboratory of Civil Aircraft Airworthiness Technology Civil Aviation University of China College of Aeronautical Engineering Civil Aviation University of China

A new passive control approach,utilizing bionic slanting riblets,is employed to mitigate the flow close to the blade endwall in a linear cascade,and its effectiveness and mechanism in controlling corner separation are investigated through numerical *** slanting riblets are positioned at the endwall upstream of the cascade channel,and the influence of riblet height,yaw angle and relative position on the control of corner separation is *** findings indicate that the application of slanting riblets can efficiently counteract corner separation across the stable operational ***,the introduction of riblets with a height of merely 0.1 times the boundary layer thickness results in a significant reduction in total pressure loss by up to 14.53%,while simultaneously enhancing the static pressure coefficient by 21.74%.Flow analysis reveals that minute vortices produced within the riblet channels tend to coalesce,forming a potent large-scale vortex near the boundary layer's base *** phenomenon results in reduced additional losses compared to conventional vortex ***,the induced vortex promotes enhanced mixing between the mainstream flow and boundary layer,inhibiting the lateral displacement of low-energy fluids within the endwall boundary ***,this delays the onset of separation vortex formation and eliminates vortex rings in the corner region,ultimately enhancing the aerodynamic efficiency of the cascade.

关键词： additional losses compressor cascade corner separation slanting riblets vortex generator

基于Magnet的三相开关磁阻电动机建模与仿真研究

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微电机 2010年第2期43卷 23-25,34页

作者：童辉罗玲陈俊硕西北工业大学自动化学院西安710129

基于Magnet仿真环境,根据电机的结构参数,建立了三相6/4极开关磁阻电动机(Switch Reluctance Motor,SRM)的系统仿真模型。通过仿真分析,得到了电机的磁场分布,静态磁链特性以及稳态运行特性;并用实际研制电机的实验结果对仿真结果进行... 详细信息

基于Magnet仿真环境,根据电机的结构参数,建立了三相6/4极开关磁阻电动机(Switch Reluctance Motor,SRM)的系统仿真模型。通过仿真分析,得到了电机的磁场分布,静态磁链特性以及稳态运行特性;并用实际研制电机的实验结果对仿真结果进行了验证,仿真结果与实验结果接近,验证了有限元仿真分析结果的正确性。

关键词：开关磁阻电动机有限元法 Magnet软件仿真

Pronounced impact of size and shape effects on creep rupture life of a K439B superalloy combustion chamber casting simulator

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China Foundry 2025年

作者： Wen-tong Liu Yi-dong Wu Lei Gao Jing-yang Chen cheng-bo Xiao Xi-dong hui State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical Materials

The size and shape effect(SSE) of components has become a critical issue for mechanical properties, application reliability, and processing. In this study, the creep rupture life(CRL) of components with different wall thicknesses and positions in a combustion chamber casing simulator made of K439B superalloy was investigated. The intrinsic mechanisms of the SSE were explored from the dendrite structure, volume fraction and size of the γ' phase, and element segregation, etc. It is shown that this casting exhibits a strong SSE of creep rupture life, characterized by a significant difference in the CRL values up to 60% with the variation of wall thickness and position in the casing. In terms of casting technology, the influence of SSE on CRL is actually determined by the cooling rate. The SSE on the creep rupture life originates from the dendrite structure(such as the secondary dendrite arm spacing), volume fraction size of the γ' phase in the dendrite trunk, and elements segregation rate. This work may have implications for the design and application of engineering components with large sizes and complex structures.

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