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Visible-light photoredox-catalyzed selective carboxylation of C(sp~2)-F bonds in polyfluoroarenes with CO2

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Chinese Journal of Catalysis 2022年第9期43卷 2388-2394页

作者： Zhi‐yu Bo si‐Shun yan Tian‐yu Gao lei Song Chuan‐Kun Ran yi He Wei Zhang guang‐Mei Cao Da‐Gang yu Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064SichuanChina

Visible light‐driven carboxylation with CO_(2) have emerged as a sustainable and powerful way to transfer waste to ***,it is still challenging for aryl fluorides due to the low reactivities of both C(sp2)−F bonds and CO_(2).Herein,we report the first photocatalytic carboxylation of aryl C−F bonds with CO_(2).The visible‐light photoredox catalysis enables selective carboxylation of strong C(sp2)−F bonds in diverse poly􀏐luoroarenes,such as penta‐,tetra‐,and tri‐fluoroarenes under mild conditions,providing a facile access to a series of important polyfluoroaryl carboxylic acids with good *** contrast to previous reports of direct capture of polyfluoroaryl radicals,mechanistic studies suggest that the reduction of fleeting polyfluoroaryl radicals into polyfluoroaryl anions might be involved in this transformation,which may open a new avenue for photocatalytic functionalization of aryl C−F bonds.

关键词： Carbon dioxide Visible-light photoredox catalysis Carboxylation C-F functionalization Polyfluoroarenes

An Azoester-containing Photoresponsive Linear Liquid Crystal Polymer with Good Mesophase Stability

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Chinese Journal of Polymer Science 2020年第8期38卷 806-813,I0005页

作者： Shu-Qiang Han ying-ying Chen Bo Xu jia Wei yan-lei yu Department of Materials Science and State Key Laboratory of Molecular Engineering of Polymers Fudan UniversityShanghai200433China

Photoresponsive linear liquid crystal polymers(LLCPs)are attractive because of the excellent stimuli-responsibility and the good *** this study,a new photoresponsive LLCP containing azoester(PC11AE6)with good mesophase stability was synthesized by ringopening metathesis *** introducing photoresponsive azoester mesogenic unit,which has high rigidity and a large lengthdiameter ratio,the resultant polymer possesses a broad mesophase temperature interval(isotropic temperature=180℃).A study on mesophase by 2D-wide angle X-ray diffraction indicated that the mesogens were orientated spontaneously into smectic A phase after *** orientated films and fibres exhibited macroscopic,rapid and reversible deformations under light irradiation as a result of the photoisomerization of azoester as confirmed by UV-Vis absorption *** anticipate that this work provides a strategy for preparing LLCP with a broad mesophase temperature range,which is positive for potential applications.

关键词： Ring-opening metathesis polymerization Liquid crystal polymers Azoester Photodeformation

汽车用铝合金在搅拌摩擦加工下的组织改性与力学性能分析

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塑性工程学报 2024年第3期31卷 200-205页

作者：高亚男张全逾魏彦杰郑镭河北石油职业技术大学汽车工程系河北承德067000 浙江万里扬股份有限公司变速箱事业部浙江金华321000 华北理工大学机械工程学院河北唐山063000

探讨了搅拌摩擦加工对汽车用YL112铝合金显微组织和力学性能的影响。结果显示,经搅拌摩擦加工后, YL112铝合金的孔隙率明显降低, α-Al内部的树枝状结构遭受严重破坏, YL112铝合金中较大的第二相粒子和针状si相得到有效分解。分解后的... 详细信息

探讨了搅拌摩擦加工对汽车用YL112铝合金显微组织和力学性能的影响。结果显示,经搅拌摩擦加工后, YL112铝合金的孔隙率明显降低, α-Al内部的树枝状结构遭受严重破坏, YL112铝合金中较大的第二相粒子和针状si相得到有效分解。分解后的产物在搅拌摩擦加工的熔核区域均匀重分布,进而使YL112铝合金的微观结构得到细化。此外,搅拌摩擦加工显著提升了YL112铝合金的抗拉强度及断后伸长率。在低延展性及高孔隙率存在的区域, YL112铝合金容易发生断裂,而经过搅拌摩擦加工处理, YL112铝合金的微观组织被重组改善,最终展现出更优异的综合力学性能。

关键词： YL112铝合金搅拌摩擦加工显微组织综合力学性能

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试析秦皇岛港东港区船舶岸电配备和使用状况

交通企业管理 2024年第5期39卷 83-85页

作者：赵舟丹雷加瑞闫钰栋秦皇岛海事局

水路运输作为最重要的运输方式,从国家到企业都在探索降低碳排放的举措,推行绿色低碳运输方式。船舶岸电系统是指在船舶正常营运靠港期间,港口向船舶供电的设备,这包括船载装置和岸基装置。船舶停靠在码头的时候,要停止使用船舶辅机,转... 详细信息

水路运输作为最重要的运输方式,从国家到企业都在探索降低碳排放的举措,推行绿色低碳运输方式。船舶岸电系统是指在船舶正常营运靠港期间,港口向船舶供电的设备,这包括船载装置和岸基装置。船舶停靠在码头的时候,要停止使用船舶辅机,转而使用陆地电源向主要船载系统供电。以电代油,既降低了碳排放,又降低了船舶营运成本,同时还能减少船舶噪声污染。

关键词：船舶岸电系统岸电设施岸电岸基建设标准规范秦皇岛港

Visible-light-driven thio-carboxylation of alkynes with CO_(2):facile synthesis of thiochromones

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Science China Chemistry 2023年第5期66卷 1457-1466页

作者： Meng Miao lei Zhu Hong Zhao lei Song si-Shun yan Li-Li Liao jian-Heng Ye yu Lan Da-Gang yu Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China College of Pharmacy Third Military Medical UniversityChongqing 400038China School of Chemistry and Chemical Engineering Chongqing Key Laboratory of Theoretical and Computational ChemistryChongqing UniversityChongqing 400030China College of Chemistry and Institute of Green Catalysis Zhengzhou UniversityZhengzhou 450001China

Difunctionalizing carboxylation of alkynes with CO_(2)is a sustainable and important strategy to generate valuable acrylate derivatives from both readily available starting *** protocols,however,always suffer from the use of excess metallic reagents and transition metal ***,we report the first thio-carboxylation of alkynes with thiophenols and CO_(2),which is a visible-light-driven and transition metal-free *** contrast to previous carboxylations of alkynes via two-electron activation of CO_(2),mechanistic and computational investigations suggest that the single-electron activation of CO_(2)is involved in the thio-carboxylation,rendering uniqueβ-*** following cyclizing acylation affords important thiochromones ***,the one-pot method features mild reaction conditions(room temperature,1 atmosphere of CO_(2)),high chemo-and regio-selectivity,easy scalability and facile derivatization of products to bioactive compounds.

关键词： carbon dioxide visible light carboxylation thiochromones

In-situ determination of onset lithium plating for safe Li-ion batteries

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Journal of Energy Chemistry 2022年第4期31卷 255-262页

作者： lei Xu yi yang Ye Xiao Wen-Long Cai yu-Xing Yao Xiao-Ru Chen Chong yan Hong yuan jia-Qi Huang School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Shanxi Research Institute for Clean Energy Tsinghua UniversityTaiyuan 030032ShanxiChina

Lithium plating in working batteries has attracted wide attention in the exploration of safe energy storage. Establishing an effective and rapid early-warning method is strongly considered but quite challenging since lithium plating behavior is determined by diverse factors. In this contribution, we present a non-destructive electrochemical detection method based on transient state analysis and threeelectrode cell configuration. Through dividing the iR drop value by the current density, the as-obtained impedance quantity(R_(i)) can serve as a descriptor to describe the change of electrochemical reaction impedance on the graphite anode. The onset of lithium plating can be identified from the sharp drop of R_(i). Once the dendritic plated lithium occurs, the extra electrochemical reactions at the lithium interfaces leads to growing active area and reduced surface resistance of the anode. We proposed a protocol to operate the batteries under the limited capacity, which renders the cell with 98.2% capacity retention after 1000 cycles without lithium plating. The early-warning method has also been validated in in-situ optical microscopy batteries and practical pouch cells, providing a general but effective method for online lithium plating detection towards safe batteries.

关键词： Lithium plating In-situ detection method Transient state analysis iR drop Three-electrode battery Lithium-ion batteries

Corrosion Behavior of High Performance Offshore Platform Steel with Chromium and Nickel Addition in the Environment Containing Chloride Ions

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Journal of Iron and Steel Research International 2015年第6期22卷 496-505页

作者： yan-lei ZHOU Xiang-jun ZHANG Tao jia Zhen-yu LIU State Key Laboratory of Rolling and Automation Northeastern University

The characterization of corrosion products formed on a high performance offshore platform steel in the en- vironment containing chloride ions has been investigated by scanning electron microscopy （SEM）, X ray diffraction （XRD）, electron probe microanalysis （EPMA） and electrochemical impedance spectroscopy （EIS）. The results re- veal that the corrosion process can be divided into the initial stage and the later stage. The main constituents of rust layers are c~ FeOOH, 13-FeOOH, y-FeOOH, Fe：^（）~ and large amounts of amorphous compounds. With increasing corrosion time, the mass fraction of a-FeOOH and Fe：~ O,, increased, while that of y-FeOOH and ^-FeOOH changed slightly. The enrichment of Cr and Ni at the inner/outer interface, especially the side of inner rust, can be observed in the later corrosion stage of Cr Ni steel, which can promote the formation of compact inner rust layer, impeding the transmission of corrosion mediums and slowing down the electrochemical reaction process.

关键词： offshore platform steel alloying element corrosion resistance rust layer electrochemical measurement

Liver test abnormalities in asymptomatic and mild COVID-19 patients and their association with viral shedding time

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World Journal of Hepatology 2022年第11期14卷 1953-1963页

作者： si-yi yu jia-rong Xie Jun-Jun Luo Hong-Peng Lu lei Xu Jun-Jie Wang Xue-Qin Chen Department of Gastroenterology Ningbo First HospitalNingbo 315010Zhejiang ProvinceChina Department of Cardiology Ningbo First HospitalNingbo 315010Zhejiang ProvinceChina Department of Information Technology Ningbo First HospitalNingbo 315010Zhejiang ProvinceChina Department of Traditional Medicine Ningbo First HospitalNingbo 315010Zhejiang ProvinceChina

BACKGROUND Asymptomatic infections and mild symptoms are common in patients infected with the Omicron variant,and data on liver test abnormalities are *** To evaluated the clinical characteristics of asymptomatic and mild coronavirus disease 2019(COVID-19)patients with abnormal liver test *** This retrospective study included 661 laboratory-confirmed asymptomatic and mild COVID-19 patients who were treated in two makeshift hospitals in Ningbo from April 5,2022 to April 29,*** information and viral shedding time were collected,and univariate and multivariate logistic regression models were performed in statistical *** Of the 661 patients,83(12.6%)had liver test abnormalities,and 6(0.9%)had liver *** liver tests revealed a reliable correlation with a history of liver disease(Psity(Psity(Psity and a history of liver disease are risk factors for liver test *** male and an older age are potential risk *** should be given to liver tests in asymptomatic and mild COVID-19 patients,which has crucial clinical significance for evaluating the viral shedding time.

关键词： COVID-19 Liver test abnormalities Asymptomatic carriers Mild cases Viral shedding time Risk factors

Defining Acupuncture-Moxibustion：A Delphi Study Protocol

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Chinese Journal of Integrative Medicine 2018年第4期24卷 260-264页

作者： LIU Bao-yan yanG Xing-yue WU Xiao-dong LIU jia LIU yan LIANG Feng-xia jia Wen GANG Wei-juan TONG yuan-yuan yanG Feng LI Hai-yan lei lei jia Li-rong SUN yu-jie China Academy of Chinese Medical Sciences Beijing(100700) China Beijing University of Chinese Medicine Beijing (100029) China Institute of Acupuncture and Moxibustion China Academy of Chinese Medical Sciences Beijing (100700) China Institute of Basic Research in Clinical Medicine China Academy of Chinese Medical Sciences Beijing (100700) China College of Acupuncture and Orthopedics Hubei University of Chinese Medicine Wuhan (430065) China Institute of Information on Traditional Chinese Medicine China Academy of Chinese Medical Sciences Beijing (100700) China Research Center of Experimental Acupuncture Science Tianjin University of Traditional Chinese Medicine Tianjin (300193) China

Background： With the worldwide use and modern development of acupuncture-moxibustion, there is disagreement on its basic definition. There has been an obstacle for clinical practice, research, and legislation. Considering this challenge, the World Federation of Acupuncture-Moxibustion Societies proposes to develop the definition and basic scope of acupuncture-moxibustion with a Delphi study. Methods： A reactive Delphi method will be used to ask a group of experts to rate the relevance and clarity of a predesigned initial item list. This list was generated by the steering committee through a literature review and group discussion. Forty experts will be selected from many disciplines and continents to ensure appropriate representation. Predefined rules will be applied to modify the items until a consensus is achieved. After achieving the consensus on all items through the survey round, the steering committee will form the definition and basic scope of acupuncture-moxibustion by organizing a literal statement with a detailed explanation.

关键词： acupuncture-moxibustion definition scope Delphi method study protocol