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Copper-catalyzed conjugate addition of allene-derived nucleophiles to alkenyl-substituted carboxamides

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Chinese Chemical Letters 2024年第3期35卷 239-242页

作者： bin fu Yue Zhao Xiuping Yuan Yanfei Li Jianjun Yin Simin Wang Tao Xiong Qian Zhang Jilin Province Key Laboratory of Organic functional Molecular Design&Synthesis Department of ChemistryNortheast Normal UniversityChangchun 130024China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Chemistry and Environmental Engineering Changchun University of Science and TechnologyChangchun 130012China

Catalytic Michael addition reaction represents a fundamental importance in organic synthetic *** corresponding conversions toward intrinsically low reactive enamide remains an ongoing *** herein report a copper-catalyzed conjugate addition of allenes toβ-substituted alkenyl amides,one of the most challenging Michael *** present method utilizes readily available allenes as the latent carbon-based nucleophiles and simple,commonβ-substituted alkenyl amides as starting materials,unlike previous methods that usually preinstall an activating group to improve the reactivity of amide or uses highly reactive stoichiometric quantities of ***,this approach shows good functional group compatibility and can be implemented under mild reaction conditions with excellent level of chemo-and regioselectivities.

关键词： CuH catalysis Allenes Unsaturated amide Conjugate addition Regioselectivity

创新水平视角下数字经济对环境污染的影响——以长江经济带40个沿线城市为例

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长江流域资源与环境 2024年第1期33卷 126-138页

作者：陈祖海符斌中南民族大学经济学院湖北武汉430074 中国武陵山乡村发展研究院湖北武汉430074

数字经济发展迅速,探究数字经济对环境污染的影响和作用机制,对于推动长江经济带高质量发展具有重要意义。基于2011~2019年长江经济带沿线40个地级及以上城市的面板数据,探讨创新水平在数字经济与环境污染之间的作用机制,利用门槛效应... 详细信息

数字经济发展迅速,探究数字经济对环境污染的影响和作用机制,对于推动长江经济带高质量发展具有重要意义。基于2011~2019年长江经济带沿线40个地级及以上城市的面板数据,探讨创新水平在数字经济与环境污染之间的作用机制,利用门槛效应模型分析其非线性关系及作用区间,进一步借助空间杜宾模型考察数字经济产生的空间溢出效应。结果表明:(1)数字经济对于本地的环境污染具有显著的抑制作用,且经过多种稳健性检验,结论依然成立。(2)创新水平是数字经济影响环境污染的重要路径,且当创新水平超过门槛值6.41后,数字经济对于环境污染的影响系数将从-0.024变为-0.042,存在边际递增的治污效果。(3)在抑制本地环境污染的同时数字经济的空间溢出效应会加剧周边地区的污染排放;产量规模的扩张可能成为污染加剧的原因,数字经济对环境污染的抑制效果被生产规模扩大带来的污染增长所覆盖;为此,需要加强地区间协同治理,避免生产规模的不合理稀释数字经济的治污效果。

关键词：数字经济创新水平环境污染门槛效应空间溢出长江经济带

Integrative bioinformatics and in vitro exploration of EVI2A expression:unraveling its immunological and prognostic implications in kidney renal clear cell carcinoma

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Oncology Research 2024年第11期32卷 1733-1746页

作者： RONG LIU SHENG LI SITU XIONG fuCUN ZHENG XIANGPENG ZHAN JIN ZENG bin fu SONGHUI XU SHAOXING ZHU RU CHEN Department of Urology Fujian Medical University Union HospitalFuzhou350000China Department of Urology The First Affiliated Hospital of Nanchang UniversityNanchang350000China

EVI2A has emerged as a significant biomarker in various diseases;however,its biological role and mechanism in kidney renal clear cell carcinoma(KIRC)remains *** used TCGA and GEO databases to analyze EVI2A gene expression comprehensively and performed pan-cancer *** relevance was evaluated through Kaplan-Meier analysis and ROC *** gene’s immune relevance was explored through analyses of the tumor microenvironment(TME),Tumor Immune Single-cell Hub(TISCH),immune checkpoints,and immunotherapy *** results indicate that EVI2A expression is upregulated in KIRC,showing correlations with tumor grade and T/N/M ***2A demonstrates high diagnostic accuracy(AUC=0.906)and predicts poor overall and progression-free survival in KIRC ***,EVI2A expression exhibits significant associations with immunity,including TME scores and specific immune cell types such as Tfh cells,CD4 memory T cells,and CD8+T *** EVI2A expression suggests increased sensitivity to PD-1/CTLA-4 and tyrosine kinase *** vitro assays confirmed the impact of EVI2A on KIRC behavior,with its knockdown resulting in reduced cell proliferation and *** conclusion,our comprehensive analysis identifies EVI2A as a promising biomarker and a novel therapeutic target for intervening in *** findings hold significant implications for further research and potential clinical applications.

关键词： EVI2A Kidney Renal Clear Cell Carcinoma(KIRC) Prognosis Immunological analysis

RuCo alloy nanoparticles embedded within N-doped porous two-dimensional carbon nanosheets:a high-performance hydrogen evolution reaction catalyst

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Tungsten 2024年第1期6卷 114-123页

作者： Jin-Hui Wang Shao-Wei Yang fu-bin Ma Yi-Ke Zhao Shi-Nuo Zhao Zheng-Yu Xiong Dong Cai Hai-Dong Shen Kai Zhu Qiu-Yu Zhang Yue-Ling Cao Tian-Shuai Wang He-Peng Zhang Research and Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518057China Xi’an Key Laboratory of functional Organic Porous Materials School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710129China School of Power and Energy Northwestern Polytechnical UniversityXi’an 710129China Chongqing Science and Technology Innovation Center of Northwestern Polytechnical University Chongqing 401135China

Developing cost-effective electrocatalysts with high activity and stability especially at high current density is of great significance for the large-scale commercial application of electrochemical water splitting to hydrogen production but still remains ***,we report an effective confinement pyrolysis strategy to fabricate embedded ruthenium-cobalt nanoclusters supported on N-doped porous two-dimensional carbon nanosheets(RuCo@CN).Markedly,the embedded structure can effectively prevent the migration,agglomeration,and leaching of nanoparticles,thus endowing the RuCo@CN catalyst with high *** be exact,high stability with up to 650 h can be achieved at high current density(-500 and-1000 mA·cm^(-2)).Besides,the RuCo@CN catalysts also exhibit highly reactive with low overpotentials of only 11mV at-10 mA·cm^(-2).Density functional theory calculations reveal that the introduction of cobalt reduces the decomposition barrier of H_(2)O for RuCo@CN alloy,thus promoting hydrogen evolution reaction.

关键词： Hydrogen evolution reaction Confinement pyrolysis strategy Mosaic structure Stability

Scale Economy Development Strategies for Deep Shale Gas in China

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China Oil & Gas 2024年第4期31卷 40-45页

作者： Huang Shihong Lu Yanlin Tang Jian Xiong Jie Hu Xi fu bin Yu Zhibo Sichuan Shale Gas Exploration and Development Co. Ltd. Development Division PetroChina Southwest Oil&Gasfield Company Research Institute of Natural Gas Economy PetroChina Southwest Oil&Gasfield Company

China has rich deep shale gas resources,which will be an important source for an increase in China’s natural gas production in a certain period in the *** its large-scale efficient development is of strategic importance in ensuring national energy *** article analyses and summarizes the opportunities and challenges in China’s scale economy development of shale ***:China’s natural gas market has immense potential,and the prospects for shale gas development are broad;the national and local governments value and support the exploration and development of shale gas;there is a rich resource base that allows for rapid production increase and stable output of deep shale gas;technological advancements will accelerate the pace of scale economy development of deep gas resources.

关键词： shale advancement strategic

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考虑视觉搜索特性的指挥控制系统KLSM

北京航空航天大学学报 2024年第9期50卷 2819-2825页

作者：郭仲赵刚付斌刘佳烨中国人民解放军军事科学院系统工程研究院北京100101 中国人民解放军93216部队北京100085 中国人民解放军93131部队北京100038

传统的击键水平模型(KLM)专注于键盘和鼠标的操作分析,适用于简单软件界面任务完成时间的快速定量评估,但将其迁移到包含复杂信息特征的指控系统软件界面评估时,却会产生较大误差。为此,基于KLM,结合用户视觉特性,面向指挥控制系统典型... 详细信息

传统的击键水平模型(KLM)专注于键盘和鼠标的操作分析,适用于简单软件界面任务完成时间的快速定量评估,但将其迁移到包含复杂信息特征的指控系统软件界面评估时,却会产生较大误差。为此,基于KLM,结合用户视觉特性,面向指挥控制系统典型任务,提出基于用户视觉搜索处理时间的物理操作时间单元指标,并通过实验获取用户视觉搜索处理时间典型参数,建立更精确的指控系统任务操作分析模型—击键和视觉搜索模型(KLSM),即考虑视觉搜索特性因素的影响。选取5类典型指控任务,进行对比实验验证,KLSM对任务完成时间的预测评估更为准确。

关键词：视觉搜索特性指控系统软件界面 KLSM 预测评估

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陈白沙诗教思想及其对高等教育的启示

现代大学教育 2024年第4期40卷 86-93页

作者：付彬刘立夫中南大学人文学院长沙410012

陈白沙的诗教思想复活了原始儒学的性灵式教育。陈白沙将诗视为最好的教育载体,他的诗展现道,透显心,实践教,联结和充实了其整个思想体系。白沙思想中,作诗并非狭隘的章句活动,它奠基于“自得之学”,属于思想之事、文教之事。诗教的本... 详细信息

陈白沙的诗教思想复活了原始儒学的性灵式教育。陈白沙将诗视为最好的教育载体,他的诗展现道,透显心,实践教,联结和充实了其整个思想体系。白沙思想中,作诗并非狭隘的章句活动,它奠基于“自得之学”,属于思想之事、文教之事。诗教的本质是情教,它关联着忘机、超越名利等活动,并让人突破血肉之心以及自我的边界,同时可以兴起真情,使人与周遭事物共同进入生机氤氲之境,陶冶高尚的道德情操。诗品决定着教育效果,上品诗方可陶铸雅健人。白沙的诗教思想不仅启发了高等教育中课程目标的德性化,而且突出高等教育课程价值导向的人文化,启迪了教学设计的情感化,提供了诗意的人文化成教学方法,其中蕴含的教育智慧对当代大学教育多有启发。

关键词：陈白沙诗教思想情感教育高等教育性灵诗学

邻亚甲醌与硫叶立德反应合成2,3-二取代苯并二氢呋喃化合物

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有机化学 2024年第1期44卷 195-203页

作者：李梦竹孟博莹兰文捷傅滨中国农业大学理学院北京100193

发展了一种简便有效的通过邻甲亚醌与硫叶立德反应合成苯并二氢呋喃化合物的方法.在二氯甲烷中和二异丙基乙基胺存在下,反应能够在室温下1 h内完成,以良好至优秀的收率得到反式-2,3-二取代二氢苯并呋喃产物.反应能够扩大到克级规模,产... 详细信息

发展了一种简便有效的通过邻甲亚醌与硫叶立德反应合成苯并二氢呋喃化合物的方法.在二氯甲烷中和二异丙基乙基胺存在下,反应能够在室温下1 h内完成,以良好至优秀的收率得到反式-2,3-二取代二氢苯并呋喃产物.反应能够扩大到克级规模,产物能够转化为潜在生物活性的苯并呋喃衍生物,并推测了可能的反应机理.

关键词：苯并二氢呋喃邻亚甲醌硫叶立德 [4+1]环加成碱催化

基于松鼠搜索算法优化Logistic-Ushiki混沌融合的数字图像加密研究

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科技通报 2024年第7期40卷 26-33页

作者：傅彬绍兴职业技术学院浙江绍兴312000

针对Logistic混沌图像加密存在结构简单、参数少、密钥空间小等缺点,本文提出基于松鼠搜索算法的Logistic-Ushiki混沌加密方法。首先提出Logistic和Ushiki融合的混沌映射模型Logistic-Ushiki,其次针对混沌参数缺乏最优的问题,从捕食者... 详细信息

针对Logistic混沌图像加密存在结构简单、参数少、密钥空间小等缺点,本文提出基于松鼠搜索算法的Logistic-Ushiki混沌加密方法。首先提出Logistic和Ushiki融合的混沌映射模型Logistic-Ushiki,其次针对混沌参数缺乏最优的问题,从捕食者概率优化和个体筛选等方面对算法进行优化,最后将改进的松鼠搜索算法对Logis⁃tic-Ushik参数进行优化,并阐述了该模型用于图像加密的过程。仿真实验中,本文算法在统计分析、相邻元素相关性、信息熵和抵抗攻击方面明显优于对比算法的性能。结果表明:该算法在图像加密方面具有较好的效果和安全性。

关键词：数字图像混沌加密