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MnBr_(2)catalyzed regiospecific oxidative Mizoroki-Heck type reaction

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Chinese Chemical Letters 2022年第5期33卷 2391-2396页

作者： Xiang chen Zhihong Zhu Shanshan Liu yi-hung chen Xiao Shen Institute for Advanced Studies Engineering Research Center of Organosilicon Compounds&MaterialsMinistry of EducationWuhan UniversityWuhan 430072China

Herein, we report an unprecedented regiospecific oxidative Mizoroki-Heck type reaction for the synthesis of α-difluoromethyl homoallylic alcohols. The reaction shows broad substrate scopes and high functional group tolerance. Late-stage functionalization of complex biologically active molecules demonstrates the synthetic potential of this transformation. Mechanistic study supports the involvement of MnBr_(2) catalyzed radical 1,2-silyl transfer.

关键词： Fluoroalkylation Mizoroki-Heck Mn catalysis Radical 1,2-silyl transfer Homoallylic alcohols

Regioselective electrochemical radical cascade cyclization of internal alkynes to selenated and trifluoromethylated dihydropyran

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Science China Chemistry 2023年第11期66卷 3178-3185页

作者： Mingming Yu Tiantian Huang Lin Zhang Muhammad Shabbir Yuhan Gao yi-hung chen Hong yi Aiwen Lei The Institute for Advanced Studies(IAS) Wuhan UniversityWuhan 430072China National Research Center for Carbohydrate Synthesis Jiangxi Normal UniversityNanchang 330022China

Dihydropyran(DHP)compounds are not only found in natural products and bioactive molecules,but also serve as important precursors in organic ***,traditional methods for the construction of such compounds are usually limited to disubstituted *** address this synthetic challenge,reported here is an efficient electrochemical strategy toward the selenated and trifluoromethylated DHP *** reaction proceeded smoothly under mild electrolysis *** broad substrate scope(>50 examples)and scalable synthesis demonstrated the complexity-building potential of the *** mechanistic studies reveal that cyclization may involve a radical *** protocol may promote the further development of diversified synthesis of multi-substituted dihydropyran.

关键词： electrochemical organic synthesis dihydropyran cascade cyclization selenylation trifluoromethylation

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Ongoing Blood Pressure Change in Both Upper Extremities: An Unusual Presentation of Aortic Dissection

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International Journal of Clinical Medicine 2011年第4期2卷 463-468页

作者： hung yi chen 不详

Aortic dissection is a critical condition requiring immediate assessment and management. Patients with this condition usually present with severe chest pain and high blood pressure. However, because of the variety of presenting symptoms and features, it is a challenge to identify this condition, and patients are frequently misdiagnosed. The potentially critical course of aortic dissection can result in tragedy. We present the case of a 46-year-old woman who initially presented with a light headache and sensory loss in her right upper limb. She had a medical history of hypertension without regular medication, and her blood pressure (BP) was 110/67 mmHg on arrival. Four days later, she was sent to the emergency department again because she experienced transient loss of consciousness lasting for a few minutes. Her BP was 94/57 mmHg in the right arm and 89/54 in the left arm. She was admitted to the hospital, and the pulses in both upper limbs were impalpable on the following day. Chest magnetic resonance imaging (MRI) was arranged, and subsequently, aortic dissection was diagnosed. The case presented with unusual characteristics, which increased the difficulty in immediate correct diagnosis.

关键词： Aortic Dissection Blood Pressure Pulseless Upper Extremities

Long-term Effects of Antihypertensive Drug Use and New-onset Osteoporotic Fracture in Elderly Patients： A Population-based Longitudinal Cohort Study

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Chinese Medical Journal 2016年第24期129卷 2907-2912页

作者： hung-yi chen Kai-Yan Ma Pei-Ling Hsieh yi-Sheng Liou Gwo-Ping Jong Institute of Pharmacy China Medical University Taichung Taiwan 40402 China Department of Pharmacy China Medical University Beigang Hospital Yunlin County Taiwan 65152 China Department of Endocrinology and Metabolism Shangluo Central Hospital Shangluo Shaanxi 726000 China Department of Family Medicine and Geriatrics School of Public Health National Defense Medical Center Taichung Veteran General Hospital Taichung Taiwan 40705 China Division of Internal Cardiology Chung Shah Medical University Hospital Chung Shan Medical University Taichung Taiwan 40201 China Department of Basic Science Central Taiwan University of Science and Technology Taichung Taiwan 40601 China

Background： Antihypertensive drugs have been linked to new-onset osteoporotic fracture （NOF）, and different classes of antihypertensive drugs may alter the risk for the development of NOF; however, the classic effect of different antihypertensive drugs on the development of NOF in the elderly has not been well studied during long-term follow-up. Methods： In this study, we investigated the association between different classic antihypertensives and the development of NOF in the elderly. This was a longitudinal cohort study performed using data from claim forms submitted to the Taiwan Bureau of National Health Insurance in Central Taiwan, China including case patients with NOF aged 65–80 years from January 2002 to December 2012 and non-NOF controls. Prescriptions for antihypertensives before the index date were retrieved from a prescription database. We estimated the hazard ratios （HR s） of NOF associated with antihypertensive use. Non-NOF controls served as the reference group. Results： A total of 128 patients with NOF were identified from among 1144 patients with hypertension during the study period. The risk of NOF after adjusting age, sex, comorbidities, and concurrent medications was higher among the users of angiotensin-converting enzyme （ACE） inhibitors （HR, 1.64; 95% confidence interval [CI], 1.01–2.66） than among nonusers. Patients who took calcium channel blockers （CCBs）（HR, 0.70; 95% CI, 0.49–0.99） were at a lower risk of developing NOF than nonusers. Loop diuretics, thiazide diuretics, angiotensin receptor blocker, beta-blocker, and alpha-blocker were not associated with the risk of NOF. Conclusions： Elderly with hypertension who take CCBs are at a lower risk of NOF and that the use of ACE inhibitors was associated with a significantly increased risk of developing NOF during the 11-year follow-up.

关键词： Antihypertensive Drugs Elderly New-onset Osteoporosis Fracture

Electrochemical flow aziridination of unactivated alkenes

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National Science Review 2023年第10期10卷 86-95页

作者：王盛淳王鹏杰李树劲陈宜鸿孙志军雷爱文 Institute for Advanced Studies (IAS) College of Chemistry and Molecular SciencesWuhan University State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration Key Laboratory of Oral Biomedicine Ministry of Education Hubei Key Laboratory of Stomatology School & Hospital of Stomatology Wuhan University Department of Oral Maxillofacial-Head Neck Oncology School and Hospital of Stomatology Wuhan University

Aziridines derived from bioactive molecules may have unique pharmacological activities,making them useful in pharmacology(*** C).Furthermore,the substitution of the epoxide moiety in epothilone B with aziridine,an analog of epoxides,yielded a pronounced enhancement in its anticancer ***,there is interest in developing novel synthetic technologies to produce aziridines from bioactive ***,known methods usually require metal catalysts,stoichiometric oxidants and/or pre-functionalized amination reagents,causing difficulty in application.A practical approach without a metal catalyst and extra-oxidant for the aziridination of bioactive molecules is in demand,yet ***,we report an ele ctro-oxidative flow protocol that accomplishes an oxidant-free aziridination of natural *** process is achieved by an oxidative sulfonamide/alkene cross-coupling,in which sulfonamide and alkene undergo simultaneous oxidation or alkene is oxidized *** anticancer treatments in cell lines have demonstrated the pharmacological activities of these aziridines,supporting the potential of this method for drug discovery.

关键词： alkene aziridination electro-oxidative cross-coupling flow chemistry N -centered radical alkene radical cation

Magneto‑Dielectric Synergy and Multiscale Hierarchical Structure Design Enable Flexible Multipurpose Microwave Absorption and Infrared Stealth Compatibility

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Nano-Micro Letters 2025年第2期17卷 401-416页

作者： chen Li Leilei Liang Baoshan Zhang yi Yang Guangbin Ji School of Electronic Science and Engineering Nanjing UniversityNanjing 210093People’s Republic of China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR cloaking mechanisms and functional integration ***,we propose a multiscale hierarchical structure design,integrating wrinkled MXene IR shielding layer and flexible Fe_(3)O_(4)@C/PDMS microwave absorption *** top wrinkled MXene layer induces the intensive diffuse reflection effect,shielding IR radiation signals while allowing microwave to pass ***,the permeable microwaves are assimilated into the bottom Fe_(3)O_(4)@C/PDMS layer via strong magneto-electric *** theoretical and experimental optimization,the assembled stealth devices realize a near-perfect stealth capability in both X-band(8–12 GHz)and long-wave infrared(8–14μm)wavelength ***,it delivers a radar cross-section reduction of−20 dB m^(2),a large apparent temperature modulation range(ΔT=70℃),and a low average IR emissivity of ***,the optimal device demonstrates exceptional curved surface conformability,self-cleaning capability(contact angle≈129°),and abrasion resistance(recovery time≈5 s).This design strategy promotes the development of multispectral stealth technology and reinforces its applicability and durability in complex and hostile environments.

关键词： Microwave absorption Radar-infrared compatible stealth Wrinkled MXene Magneto-dielectric synergy Multifunction

Coordinated Control Strategy of New Energy Power Generation System with Hybrid Energy Storage Unit

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Energy Engineering 2025年第1期122卷 167-184页

作者： Yun Zhang ZifenHan Biao Tian Ning chen yi Fan School of Mechano-Electronic Engineering Xidian UniversityXi’an710071China Electric Power Control Center State Grid Gansu Electric Power CompanyLanzhou730030China Electric Power Control Center State Grid Gansu Electric Power Company Zhangye Power Supply BranchZhangye734000China

The new energy power generation is becoming increasingly important in the power *** as photovoltaic power generation has become a research hotspot,however,due to the characteristics of light radiation changes,photovoltaic power generation is unstable and random,resulting in a low utilization rate and directly affecting the stability of the power *** solve this problem,this paper proposes a coordinated control strategy for a newenergy power generation system with a hybrid energy storage unit based on the lithium iron phosphate-supercapacitor hybrid energy storage ***,the variational mode decomposition algorithm is used to separate the high and low frequencies of the power signal,which is conducive to the rapid and accurate suppression of the power fluctuation of the energy storage ***,the fuzzy control algorithm is introduced to balance the power between energy *** this paper,the actual data is used for simulation,and the simulation results show that the strategy realizes the effective suppression of the bus voltage fluctuation and the accurate control of the internal state of the energy storage unit,effectively avoiding problems such as overshoot and over-discharge,and can significantly improve the stability of the photovoltaic power generation systemand the stability of the Direct Current *** is of great significance to promote the development of collaborative control technology for photovoltaic hybrid energy storage units.

关键词： Photovoltaic power suppression hybrid energy storage unit variationalmodal decomposition fuzzy control power distribution control

Tuning the interfacial reaction environment via pH-dependent and induced ions to understand C–N bonds coupling performance in NO3- integrated CO2 reduction to carbon and nitrogen compounds over dual Cu-based N-doped carbon catalyst

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Journal of Energy Chemistry 2025年第1期100卷 273-285页

作者： Tianhang Zhou chen Shen Zhenghao Wu Xingying Lan yi Xiao College of Carbon Neutrality Future Technology State Key Laboratory of Heavy Oil Processing China University of Petroleum (Beijing) Institute of Materials Science TU Darmstadt Department of Chemistry Xi'an Jiaotong-Liverpool University Department of Mechanical and Mechatronics Engineering and Waterloo Institute of Nanotechnology University of Waterloo Waterloo

Dual atomic catalysts （DAC）,particularly copper （Cu2）-based nitrogen （N） doped graphene,show great potential to effectively convert CO2and nitrate （NO3-） into important industrial chemicals such as ethylene,glycol,acetamide,and urea through an efficient catalytical process that involves C–C and C–N ***,the origin of the coupling activity remained unclear,which substantially hinders the rational design of Cu-based catalysts for the N-integrated CO2reduction reaction （CO2RR）.To address this challenge,this work performed advanced density functional theory calculations incorporating explicit solvation based on a Cu2-based N-doped carbon (Cu2N6C10) catalyst for *** calculations are aimed to gain insight into the reaction mechanisms for the synthesis of ethylene,acetamide,and urea via coupling in the interfacial reaction *** to the sluggishness of CO2,the formation of a solvation electric layer by anions （F-,Cl-,Br-,and I-） and cations (Na+,Mg2+,K+,and Ca2+) leads to electron transfer towards the Cu *** process significantly accelerates the reduction of *** results reveal that*CO intermediates play a pivotal role in N-integrated ***,the Cu2-based N-doped carbon catalyst examined in this study has demonstrated the most potential for C–N coupling to *** findings reveal that through the process of a condensation reaction between*CO and NH2OH for urea synthesis,*NO3-is reduced to*NH3,and*CO2to*CCO at dual Cu atom *** dual-site reduction facilitates the synthesis of acetamide through a nucleophilic reaction between NH3and the ketene ***,we found that the I-and Mg2+ions,influenced by pH,were highly effective for acetamide and ammonia synthesis,except when F-and Ca2+were ***,the mechanisms of C–N bond formation were investigated via ab-initio molecular dynamics simulations,and we found that adjusting the micro-environment can change the dominant side reaction,shift

关键词： Condensation reactions

Electrocatalytic cleavage of a lignin β-O-4 model compound and coupling with nitrogen-containing aromatics using Prussian blue analogue-derived nickel–cobalt spinel

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Journal of Energy Chemistry 2025年第1期100卷 628-636页

作者： yi Qi Xueying chen Bowen Liu Xuliang Lin Xueqing Qiu Yanlin Qin Guangdong Provincial Key Laboratory of Plant Resources Biorefinery School of Chemical Engineering and Light Industry Guangdong University of Technology Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center Guangdong Basic Research Center of Excellence for Ecological Security and Green Development Guangdong University of Technology

Electrochemical conversion of lignin for the production of high-value heterocyclic aromatic compounds has great *** demonstrate the targeted synthesis and cation modulation of NiCo2O4spinel nanoboxes,synthesized via cation exchange and calcination *** catalysts exhibit excellent efficacy in the electrocatalytic conversion of lignin model compounds,specifically 2-phenoxy-1-phenylethanol,into nitrogen-containing aromatics,achieving high conversion rates and *** catalysts were synthesized via a cation exchange and calcination oxidation process,using Prussian blue nanocubes as *** porous architecture and polymetallic composition of the NiCo2O4spinel demonstrated superior performance in electrocatalytic oxidative coupling,achieving a 99.2 wt%conversion rate of the 2-phenoxy-1-phenylethanol with selectivities of 37.5 wt%for quinoline derivatives and 31.5 wt%for *** innovations include the development of a sustainable one-pot synthesis method for quinoline derivatives,the elucidation of a multistage reaction pathway involving CAO bond cleavage,hydroxyaldol condensation,and CAN bond formation,and a deeper mechanistic understanding derived from DFT *** work establishes a new strategy for lignin valorization,offering a sustainable route to produce high-value nitrogen-containing aromatics from renewable biomass under mild conditions,without the need for additional reagents.

关键词： Spinel Biomass valorization Electrocatalysis Lignin oxidation Coupling