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Recent advances in cycloaddition of CO_(2) with epoxides:halogen-free catalysis and mechanistic insights

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Frontiers of Chemical Science and Engineering 2023年第12期17卷 1879-1894页

作者： Jiaxin Li Chengguang Yue Wenhao Ji Bangman Feng mei-yan wang Xinbin Ma School of Chemical Engineering and Technology Key Laboratory for Green Chemical Technology of Ministry of EducationCollaborative Innovation Center of Chemical Science and EngineeringTianjin UniversityTianjin 300072China Zhejiang Institute of Tianjin University Ningbo Key Laboratory of Green Petrochemical Carbon Emission Reduction Technology and EquipmentNingbo 315200China

The atom-economical cycloaddition of CO_(2) with epoxides to synthesize cyclic carbonates is a promising route for valuable utilization of CO_(2).Halogenide such as alkali metal halides and quaternary ammonium salt have been developed as the efficient ***,the spilled halogen causes equipment corrosion and affects the product *** address these concerns,the halogen-free cycloaddition of CO_(2) with epoxides has always been *** this review,we systematically discussed the halogen-free catalysis for cycloaddition of CO_(2) with epoxides from the mechanistic insights,aiming to promote the development of efficient halogen-free *** types of catalysts,i.e.,alternatives of halogen nucleophiles for epoxide activation,and bifunctional catalysts with Lewis acid-base sites for synergistic activation of CO_(2) and epoxides are summarized and ***,metal oxides as the potential halogen-free catalysts are highlighted due to their flexible acid-base sites for synergistic activation of CO_(2) and epoxides,facile preparation,and low cost.

关键词： carbon dioxide halogen-free catalysis cyclic carbonate mechanistic insight

Pt-modulated Cu/SiO_(2) catalysts for efficient hydrogenation of CO_(2)-derived ethylene carbonate to methanol and ethylene glycol

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Chinese Journal of Chemical Engineering 2022年第1期35卷 366-373页

作者： Busha Assaba Fayisa Yushan Xi Youwei yang Yueqi Gao Antai Li mei-yan wang Jing Lv Shouying Huang Yue wang Xinbin Ma Key Laboratory for Green Chemical Technology of Ministry of Education Collaborative Innovation Center of Chemical Science and EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Zhejiang Institute of Tianjin University Ningbo 315201China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China

Copper-based catalysts were widely used in the heterogeneous selective hydrogenation of ethylene carbonate(EC),a key step in the indirect conversion of CO_(2) to ***,a high H_(2)/EC molar ratio in feed is required to achieve favorable activity and the methanol selectivity still needs to be ***,we fabricated a series of Pt-modulated Cu/SiO_(2) catalysts and investigated their catalytic performance for hydrogenation of EC in a fixed bed *** modulating the Pt amount,the optimal 0.2Pt-Cu/SiO_(2) catalyst exhibited the highest catalytic performance with99%EC conversion,over 98%selectivity to ethylene glycol and 95.8%selectivity to methanol at the H_(2)/EC ratio as low as 60 in *** addition,0.2Pt-Cu/SiO_(2) catalyst showed excellent stability for 150 h on stream over different H_(2)/EC ratios of *** is demonstrated a proper amount of Pt could significantly lower the H_(2)/EC molar ratio,promote the reducibility and dispersion of copper,and also enhance surface density of Cu+*** could be due to the strong interaction of Cu and Pt induced by formation of alloyed Pt single atoms on the Cu ***,a relatively higher amount of Pt would deteriorate the catalytic activity,which could be due to the surface coverage and aggregation of active *** findings may enlighten some fundamental insights for further design of Cu-based catalysts for the hydrogenation of carbon–oxygen bonds.

关键词： CO_(2) Ethylene carbonate Hydrogenation Pt-Cu/SiO_(2)catalyst Ethylene glycol Methanol

Electrocarboxylation of CO_(2) with Organic Substrates:Toward Cathodic Reaction

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Transactions of Tianjin University 2023年第4期29卷 254-274页

作者： He Yao mei-yan wang Chengguang Yue Bangman Feng Wenhao Ji Chunbo Qian Shengping wang Sheng Zhang Xinbin Ma School of Chemical Engineering and Technology Key Laboratory for Green Chemical Technology of Ministry of EducationCollaborative Innovation Center of Chemical Science and EngineeringTianjin UniversityTianjin 300072China Ningbo Key Laboratory of Green Petrochemical Carbon Emission Reduction Technology and Equipment Zhejiang Institute of Tianjin UniversityNingbo 315200China

Electrocarboxylation of carbon dioxide(CO_(2))using organic substrates has emerged as a promising method for the sustainable synthesis of value-added carboxylic acids due to its renewable energy source and mild reaction *** reactivity and product selectivity of electrocarboxylation are highly dependent on the cathodic behavior,involving a sequence of electron transfers and chemical ***,it is necessary to understand the cathodic reaction mechanisms for optimizing reaction performance and product *** this work,a review of recent advancements in the electrocarboxylation of CO_(2)with organic substrates based on different cathodic reaction pathways is presented to provide a reference for the development of novel methodologies of CO_(2)***,cathodic reactions are particularly classified into two categories based on the initial electron carriers(i.e.,CO_(2)radical anion and substrate radical anion).Furthermore,three cathodic pathways(ENE(N),ENED,and EDEN)of substrate radical anion-induced electrocarboxylation are discussed,which differ in their electron transfer sequence,substrate dissociation,and nucleophilic reaction,to highlight their implications on reactivity and product selectivity.

关键词： Carbon dioxide Electrocatalysis Carboxylation Cathodic reaction Carboxylic acids

Self-Powered Flexible Multicolor Electrochromic Devices for Information Displays

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Research 2024年第2期2023卷 529-540页

作者： Wenzhao Xue Yun Zhang Feng Liu Yao Dou mei yan Wenshou wang School of Chemistry and Chemical Engineering University of JinanJinan 250022P.R.China

The development of self-powered flexible multicolor electrochromic(EC)systems that could switch different color without an external power supply has remained extremely ***,a new trilayer film structure for achieving self-powered flexible multicolor EC displays based on self-charging/discharging mechanism is proposed,which is simply assembled by sandwiching an ionic gel film between 2 cathodic nickel hexacyanoferrate(NiHCF)and Prussian blue(PB)nanoparticle films on indium tin oxide *** display exhibits independent self-powered color switching of NiHCF and PB films with fast responsive time and high reversibility by selectively connecting the Al wire as anodes with the 2 EC *** switching is thus achieved through a color overlay effect by superimposing the 2 EC films,including green,blue,yellow,and *** bleaching/coloration process of the displays is driven by the discharging/self-charging mechanism for NiHCF and PB films,respectively,ensuring the self-powered color switching of the displays reversibly without an external power *** is further demonstrated that patterns can be easily created in the self-powered EC displays by the spray-coating method,allowing multicolor changing to convey specific ***,a self-powered ionic writing board is demonstrated based on the self-powered EC displays that can be repeatedly written freehand without the need of an external power *** believe that the design concept may provide new insights into the development of self-powered flexible multicolor EC displays with self-recovered energy for widespread applications.

关键词： connecting repeatedly powered

Evaluation of the effects of health education interventions for hypertensive patients based on the health belief model

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World Journal of Clinical Cases 2024年第15期12卷 2578-2585页

作者： Hong-mei wang Ying Chen yan-Hua Shen Xiao-mei wang Department of Emergency Lishui Second People's HospitalLishui 323000Zhejiang ProvinceChina Department of Pancreatic and Biliary Surgery The First Affiliated Hospital of China Medical UniversityShenyang 110002Liaoning ProvinceChina

BACKGROUND Hypertension is a major risk factor for cardiovascular disease and stroke,and its prevalence is increasing *** education interventions based on the health belief model(HBM)can improve the knowledge,attitudes,and behaviors of patients with hypertension and help them control their blood *** To evaluate the effects of health education interventions based on the HBM in patients with hypertension in *** Between 2021 and 2023,140 patients with hypertension were randomly assigned to either the intervention or control *** intervention group received health education based on the HBM,including lectures,brochures,videos,and counseling sessions,whereas the control group received routine *** were measured at baseline,three months,and six months after the intervention and included blood pressure,medication adherence,self-efficacy,and perceived benefits,barriers,susceptibility,and *** The intervention group had significantly lower systolic blood pressure[mean difference(MD):-8.2 mmHg,P<0.001]and diastolic blood pressure(MD:-5.1 mmHg,P=0.002)compared to the control group at six *** intervention group also had higher medication adherence(MD:1.8,P<0.001),self-efficacy(MD:12.4,P<0.001),perceived benefits(MD:3.2,P<0.001),lower perceived barriers(MD:-2.6,P=0.001),higher perceived susceptibility(MD:2.8,P=0.002),and higher perceived severity(MD:3.1,P<0.001)than the control group at six *** Health education interventions based on the HBM effectively improve blood pressure control and health beliefs in patients with hypertension and should be implemented in clinical practice and community settings.

关键词： Hypertension Health education Health belief model Blood pressure control Randomized controlled trial

A polarized^(3)He system based on metastability-exchange optical pumping

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 72-81页

作者： Yuting wang Liangyong Wu Kaiyuan Zhang mei Peng Siyu Chen Haiyang yan State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Fudan UniversityShanghai 200433China Key Laboratory of Neutron Physics Institute of Nuclear Physics and ChemistryChina Academy of Engineering PhysicsMianyang 621900China

Hyperpolarized^(3)He nuclei have emerged as a significantly important approach in quantum precision measurement techniques,with extensive applications in fundamental physics,magnetometry,metrology,and *** this study,we report on the design and implementation of a^(3)He polarization system at the China Mianyang Research Reactor(CMRR),utilizing the metastabilityexchange optical pumping(MEOP)*** employed a Merritt coil system consisting of four square coils to furnish a uniform holding *** deployed a 2 W fiber laser to pump the metastable^(3)He atoms and conducted free induction decay(FID)detection of the polarized^(3)He nuclei using both pickup coil and optical *** the optical method,we used a50 m W linearly polarized distributed Bragg reflector(DBR)laser as the *** applied transverse light absorption polarimetry to measure the absolute nuclear polarization of the ground-state^(3)*** have developed cell fabrication capabilities at the CMRR,and cells at various pressures ranging from 100 to 1000 Pa have been fabricated and *** a typical borosilicate cell with 100 Pa pressure,the absolute polarization is measured as Pn≈70%,and the transverse relaxation time is estimated as T2≈0.5 ***,we constructed a few aluminosilicate cells,each carefully filled with pure^(3)He at a pressure of 100 ***,we conducted a comprehensive evaluation of their performance in the context of MEOP.

关键词： metastability exchange optical pumping polarized^(3)He magnetic resonance

Enhanced selective hydrogenation of glycolaldehyde to ethylene glycol over Cu^(0)-Cu^(+)sites

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Chinese Journal of Chemical Engineering 2023年第5期57卷 141-150页

作者： Qi yang Weikang Dai Maoshuai Li Jie Wei Yi Feng Cheng yang Wanxin yang Ying Zheng Jie Ding mei-yan wang Xinbin Ma Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Selective hydrogenation of hydroxyaldehydes to polyalcohols is challenging due to the competitive hydrogenation of C=O and *** study develops heterogeneous Cu catalysts for the selective synthesis of ethylene glycol via batch liquid-phase hydrogenation of ***_(2)supported Cu,fabricated by ammonia evaporation,enables to catalyze the C=O bond hydrogenation with retaining the CAO bond intact,yielding higher selective hydrogenation activity with ethylene glycol selectivity up to 99.8%relative to MgO,Al_(2)O_(3),CeO_(2),and TiO_(2)supports and Cu/SiO_(2)synthesized by deposition–precipitation and *** confirm that highly efficient 20Cu/SiO_(2)-AE-623 K catalyst fabricated by ammonia evaporation is featured with larger Cu^(0)and Cu^(+)surface areas,of which the Cu^(+)species created from reducing copper phyllosilicate exhibit higher reactivity.A synergistic effect between Cu^(+)and Cu^(0)facilitates the selective adsorption/activation of glycolaldehyde on Cu^(+)sites and the dissociation of H_(2)on Cu^(0)sites,bringing a remarkable improvement in the selective hydrogenation performance.

关键词： Hydrogenation Multiphase reaction Biomass Copper phyllosilicate Ammonia evaporation

The deteriorated degradation resistance of Mg alloy microtubes for vascular stent under the coupling effect of radial compressive stress and dynamic medium

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Journal of Magnesium and Alloys 2024年第2期12卷 573-585页

作者： Mengyao Liu Yabo Zhang Qingyuan Zhang yan wang Di mei Yufeng Sun Liguo wang Shijie Zhu Shaokang Guan School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Henan Key Laboratory of Advanced Magnesium Alloys Zhengzhou 450002China Key Laboratory of Advanced Materials Processing&Mold Ministry of Education Zhengzhou 450002China

The degradation of Mg alloys relates to the service performance of Mg alloy biodegradable *** order to investigate the degradation behavior of Mg alloys as vascular stent materials in the near service environment,the hot-extruded fine-grained Mg-Zn-Y-Nd alloy microtubes,which are employed to manufacture vascular stents,were tested under radial compressive stress in the dynamic Hanks'Balanced Salt Solution(HBSS).The results revealed that the high flow rate accelerates the degradation of Mg alloy microtubes and its degradation is sensitive to radial compressive *** results contribute to understanding the service performance of Mg alloys as vascular stent materials.

关键词： Mg alloy Microtubes Degradation behavior Radial compressive stress Dynamic conditions

Polyoxometalate-based ionic liquids-promoted CO_2 conversion

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Science China Chemistry 2016年第5期59卷 507-516页

作者： mei-yan wang Ran Ma Liang-Nian He State Key Laboratory and Institute of Elemento-Organic Chemistry Collaborative Innovation Center of Chemical Science and Engineering Nankai University

Polyoxometalates(POMs) are a class of molecular metal oxides, showing numerous applications in various chemical processes due to their unique acid/base and redox features. By adjusting the tunable molecular structures of the anions and counter cations, plenty of POM-based ionic liquids(POM-based ILs) have been fabricated to be used in various fields, such as catalysis, structural chemistry and material science. As a class of excellent catalysts, POM-based ILs have shown advantages in the emerging field of CO_2 utilization such as CO_2 capture, cycloaddition of CO_2 to epoxides, and reduction of CO_2, owing to the efficient activation of CO_2 by POM anions. This review summarizes recent advances in the catalysis of POM-based ILs, and particularly highlights the areas that are related to CO_2 conversion.

关键词：多金属氧酸盐离子液体 CO2 转化 POMS 应用程序分子结构结构化学