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Asymmetric annulations based on cycloisomerization of cyclopropyl tethered allenyl ketones by bimetallic relay catalysis

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Science China Chemistry 2023年第10期66卷 2803-2809页

作者： Jun He Wen Liu Jing Zhang ziwei Zhong Lili Lin Xiaoming feng Key Laboratory of Green Chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu 610064China

The diastereo-and enantioselective tandem cycloisomerization/[4+2]-cycloaddition reaction of cyclopropyl tethered allenyl ketones withα,β-unsaturated carbonyl compounds was realized firstly under mild reaction conditions by using bimetallic silver(I)/chiral metal-N,N′-dioxide catalysts,providing a facile and atom-economic route to enantioenriched polysubstituted furopyran derivatives with good *** transition state models were proposed to explain the stereoinduction.

关键词： asymmetric catalysis bimetallic relay cyclopropyl tethered allenyl ketones [4+2]-cycloaddition furopyran

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Asymmetric catalytic alkylation of vinyl azides with 3-bromo oxindoles: water-assisted chemo-and enantiocontrol

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Science China Chemistry 2023年第3期66卷 799-807页

作者： ziwei Zhong Lichao Ning Yican Lu Jiuqi Tan Lili Lin Xiaoming feng Key Laboratory of Green Chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu 610064China

A highly chemo-and enantioselective alkylation of vinyl azides with 3-bromo-3-substituted oxindoles was achieved through a chiral N,N′-dioxide/Ni(OTf)2-mediated conjugate addition/water addition/elimination tandem process. Water was critical to the chemo-and enantioselectivity. The hydrated Na3PO4 acted as both a base and a reservoir to regulate the amount of water in solution. A wide range of enantioenriched oxindoles having α-carbonyl-substituted all-carbon quaternary stereocenters were achieved in good yields and good ee values(51 examples, up to 90% yield, 97% ee). Easy transformations of products to analogues of(+)-physovenine and(+)-desoxyeseroline enhanced the synthetic value. Mechanistic studies including control experiments, kinetic studies, and density functional theory(DFT) calculations, enabled a proposition of a possible catalytic cycle along with transition states to elucidate the reaction process and chiral induction.

关键词： asymmetric catalysis water assistance tandem reaction vinyl azide ketone surrogate

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生物反馈训练对哮喘患者生活质量的影响

护理学杂志 2008年第11期23卷 55-56页

作者：李莹邱碧秀张慧周郁秋冯子维哈尔滨医科大学大庆校区护理系黑龙江大庆163319

目的探讨生物反馈训练对哮喘患者生活质量的影响。方法将60例哮喘患者分为干预组和对照组各30例;对照组予药物治疗和常规护理,干预组在此基础上给予生物反馈训练4周;于干预前后(6周后)评定哮喘控制效果和最大呼气高峰流速(PEF),采用哮... 详细信息

目的探讨生物反馈训练对哮喘患者生活质量的影响。方法将60例哮喘患者分为干预组和对照组各30例;对照组予药物治疗和常规护理,干预组在此基础上给予生物反馈训练4周;于干预前后(6周后)评定哮喘控制效果和最大呼气高峰流速(PEF),采用哮喘生活质量评定量表(AQLQ)评定两组生活质量。结果干预后哮喘控制效果、PEF值及AQLQ中活动受限、哮喘症状、心理状况3个维度和总分观察组显著优于对照组(均P<0.05)。结论生物反馈训练有利于改善患者的肺功能,有助于控制病情和提高其生活质量。

关键词：哮喘生物反馈生活质量护理

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经腹腔镜手术治疗输尿管结石20例报告

临床泌尿外科杂志 2005年第10期20卷 626-627页

作者：徐战平王行环罗耀雄冯自卫刘久敏广东省人民医院泌尿外科广州510080

目的:探讨腹腔镜治疗输尿管结石的操作要点和经验.方法:采用经腹膜后途径腹腔镜技术行输尿管中、上段切开取石术16例,经腹腔途径行输尿管下段切开取石4例,术前均行体外冲击波碎石(ESWL)或输尿管镜下碎石(URSL)治疗失败;结石直径0.9～2.6... 详细信息

目的:探讨腹腔镜治疗输尿管结石的操作要点和经验.方法:采用经腹膜后途径腹腔镜技术行输尿管中、上段切开取石术16例,经腹腔途径行输尿管下段切开取石4例,术前均行体外冲击波碎石(ESWL)或输尿管镜下碎石(URSL)治疗失败;结石直径0.9～2.6 cm.结果:20例均获成功,手术时间30～95 min,平均51 min;术中出血量10～50 ml,平均24 ml;随访6个月,无并发症.结论:腹腔镜下输尿管切开取石术是安全有效的微创技术,输尿管下段切开取石经腹腔途径简单、易行.

关键词：腹腔镜手术输尿管结石

Toxicity mechanisms and bioavailability of copper to fish based on an adverse outcome pathway analysis

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Journal of Environmental Sciences 2023年第5期127卷 495-507页

作者： Wei Liao ziwei Zhu Chenglian feng Zhenfei Yan Yajun Hong Daqing Liu Xiaowei Jin State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Wetland Research Center Jiangxi Academy of ForestryNanchang 330032China Key Laboratory of Poyang Lake Environment and Resource Utilization Ministry of EducationSchool of Environmental and Chemical EngineeringNanchang UniversityNanchang 330031China Jiangxi Irrigation Experiment Central Station Nanchang 330201China China National Environmental Monitoring Centre Beijing 100012China

Copper(Cu)exists in a variety of forms in different aquatic environments,and affects their *** this study we provide a systematic review on toxicity of Cu which focuses on identifying evidence in the mechanisms of Cu toxicity,and apply an adverse outcome pathway(AOP)analysis to identify multiple potential mechanisms and their interactions of Cu toxicity to *** analysis process included the mechanisms of behavior toxicant,oxidative toxicant,ion regulation disruption toxicity,as well as endocrine disruption *** was found that at low levels of Cu exposure,swimming,avoid predators,locating prey and other sensory functions will be impaired,and the organism will suffer from metabolic alkalosis and respiratory acidosis following the inhibition of the carbonic anhydrase *** main pathway of acute toxicity of Cu to fish is the inhibition of the Na^(+)/K^(+)-ATPase enzyme,and lead to reduced intracellular sodium absorption,as well as Cu-induced increased cell permeability,in turn resulting in increased sodium ion loss,leading to cardiovascular collapse and respiratory *** endocrine disruption toxicity of Cu to fish caused growth inhibition and reproductive *** addition,there are several key pathways of Cu toxicity that are affected by hardness(e.g.,Ca^(2+))and intracellular DOC concentrations,including inhibiting Cu-induction,improving branchial gas exchange,altering membrane transport functions,decreasing Na+loss,and increasing Na+*** results of the AOP analysis will provide a robust framework for future directed research on the mechanisms of Cu toxicity.

关键词： Copper Toxic effect Adverse outcome pathway Aquatic environment Risk assessment

Molecular dynamics simulation of graphene sinking during chemical vapor deposition growth on semi-molten Cu substrate

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npj Computational Materials 2020年第1期6卷 1548-1557页

作者： ziwei Xu Guanghui Zhao Lu Qiu Xiuyun Zhang Guanjun Qiao feng Ding School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China Centre for Multidimensional Carbon Materials Institute for Basic ScienceUlsan 44919Korea School of Materials Science and Engineering Ulsan National Institute of Science and Technology(UNIST)Ulsan 44919Korea College of Physics Science and Technology Yangzhou UniversityYangzhou 225002China

Copper foil is the most promising catalyst for the synthesis of large-area,high-quality monolayer ***,it has been found that the Cu substrate is semi-molten at graphene growth *** this study,based on a self-developed C–Cu empirical potential and density functional theory(DFT)methods,we performed systematic molecular dynamics simulations to explore the stability of graphene nanostructures,i.e.,carbon nanoclusters and graphene nanoribbons,on semi-molten Cu substrates.

关键词： dynamics semi monolayer

肿瘤科护士心理资本在自我效能感与创新能力间的中介效应

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循证护理 2023年第18期9卷 3367-3370页

作者：冯紫薇王艳华王晶张娴李琼琼孙晗玉徐州医科大学附属医院江苏221000

目的:探讨肿瘤科护士的心理资本、自我效能感、创新能力间的关系,从而为提升肿瘤科护士创新能力提供不同视角。方法:应用护士创新行为量表、心理资本量表、一般自我效能感量表对徐州医科大学附属医院肿瘤科100名护士进行问卷调查。结果... 详细信息

目的:探讨肿瘤科护士的心理资本、自我效能感、创新能力间的关系,从而为提升肿瘤科护士创新能力提供不同视角。方法:应用护士创新行为量表、心理资本量表、一般自我效能感量表对徐州医科大学附属医院肿瘤科100名护士进行问卷调查。结果:肿瘤科护士的创新能力得分为(30.95±4.15)分,处于中等水平;肿瘤科护士自我效能感和创新能力呈正相关(r=0.937,P<0.01),心理资本与创新能力、自我效能感均呈正相关(r值为0.874,0.812,均P<0.01);肿瘤科护士心理资本在自我效能感与创新能力间起部分中介作用,中介效应贡献率为28.94%。结论:肿瘤科护士的创新能力处于中等水平,心理资本在肿瘤科护士自我效能感与创新能力中起部分中介作用,护理管理者应重视心理资本的开发和培育,充分发挥自我效能感的作用以提高护士的创新能力。

关键词：创新能力心理资本自我效能感肿瘤科护士中介效应护理

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高黏流体液滴形成机理研究

河北工业大学学报 2023年第4期52卷 48-56页

作者：段润泽张晓磊冯紫薇赵若霖杨华刘联胜河北工业大学能源与环境工程学院天津300401 河北省热科学与能源清洁利用重点实验室天津300401

制药业是我国重点发展的领域,滴丸制剂是制药业发展中的一种制备类型,高品质滴丸的研发引起了众多制药企业的兴趣。本文通过数值计算的方法对滴丸(高黏液滴)的形成进行研究,探讨滴丸形成的机理,研究滴头壁厚、液体入口速度、液体密度、... 详细信息

制药业是我国重点发展的领域,滴丸制剂是制药业发展中的一种制备类型,高品质滴丸的研发引起了众多制药企业的兴趣。本文通过数值计算的方法对滴丸(高黏液滴)的形成进行研究,探讨滴丸形成的机理,研究滴头壁厚、液体入口速度、液体密度、表面张力及黏度等参数对滴丸形成的规律,研究发现:颈缩线断裂是形成滴丸的主要原因;壁面厚度对滴丸形成过程中液体浸润有一定的影响;随着入口速度和液体表面张力的增加,滴丸体积随之增加。然而随着液体密度和黏度的增加,滴丸体积逐渐减小。

关键词：滴丸体积壁面厚度滴头直径颈缩线断裂

TSILNet:A novel hybrid model for energy disaggregation based on two-stage improved TCN combined with IECA-LSTM

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Building Simulation 2024年第11期17卷 2083-2095页

作者： ziwei Zhu Mengran Zhou feng Hu Kun Wang Guangyao Zhou Weile Kong Yijie Hu Enhan Cui School of Electrical and Information Engineering Anhui University of Science and TechnologyHuainan232001AnhuiChina

Non-intrusive load monitoring(NILM)technology aims to infer the operation information of electrical appliances from the total household load signals,which is of great significance for energy conservation and ***,existing methods are difficult to effectively capture the complex nonlinear features of the power consumption flow,which affects the energy disaggregation *** this end,this paper designs a method based on temporal convolutional network(TCN),efficient channel attention(ECA),and long short-term memory(LSTM).The method first creatively proposes a two-stage improved TCN(TSTCN),which overcomes its problems of extracting discontinuous information and poor correlation of long-distance information while enhancing the ability to extract high-level load *** a novel improved ECA attention mechanism(IECA)is embedded,which is also combined with the skip connection technique to pay channel-weighted attention to important feature maps and promote information ***,the LSTM with strong temporal memory capability is introduced to learn the dependencies in the load power sequence and realize load *** on two real-world datasets,REDD and UK-DALE,show that the proposed model significantly outperforms other comparative NILM algorithms and achieves satisfactory tracking with the actual appliance operating *** results show that the mean absolute error(MAE)of all appliances decreases by 18.67%on average,and the F1 score improves by 38.70%.

关键词： deep learning non-intrusive load monitoring(NILM) energy disaggregation temporal convolutional network(TCN) attention mechanism long short-term memory(LSTM)