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Recent Advances in Electrochemical Oxidation to Construct C–O Bonds

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Transactions of Tianjin University 2022年第6期28卷 482-505页

作者： Lei Zhan Wan-Jie Wei Cai-nai jiang Lei Gao Xian-Li Ma Guangxi Key Laboratory of Drug Discovery and Optimization Guangxi Engineering Research Center for Pharmaceutical Molecular Screening and Druggability EvaluationSchool of PharmacyGuilin Medical UniversityGuilin 541004China

C–O bonds are widely found in pharmaceuticals and natural products and have various pharmacological ***,developing eff ective strategies for constructing compounds containing C–O bonds has become a research hotspot among *** electrochemical synthesis is a green,mild,and effi cient strategy that shows great potential in the synthesis of compounds containing C–O *** review introduces the reactions of compounds containing C–O bonds recently constructed by electrochemical methods and expounds the corresponding reaction mechanism to provide a reference for applying such reactions in organic synthesis.

关键词： Organic electrochemistry C–O bond Green synthesis

All-electrical switching of a topological non-collinear antiferromagnet at room temperature

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National Science Review 2023年第2期10卷 123-130页

作者： Yongcheng Deng Xionghua Liu Yiyuan Chen Zongzheng Du nai jiang Chao Shen Enze Zhang Houzhi Zheng Hai-Zhou Lu Kaiyou Wang State Key Laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of Sciences Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and Technology (SUSTech) International Quantum Academy Beijing Academy of Quantum Information Sciences Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences

Non-collinear antiferromagnetic Weyl semimetals,combining the advantages of a zero stray field and ultrafast spin dynamics,as well as a large anomalous Hall effect and the chiral anomaly of Weyl fermions,have attracted extensive ***,the all-electrical control of such systems at room temperature,a crucial step toward practical application,has not been ***,using a small writing current density of around 5 × 106A·cm-2,we realize the all-electrical current-induced deterministic switching of the non-collinear antiferromagnet Mn3Sn,with a strong readout signal at room temperature in the Si/SiO2/Mn3Sn/AlOxstructure,and without external magnetic field or injected spin *** simulations reveal that the switching originates from the current-induced intrinsic non-collinear spin-orbit torques in Mn3Sn *** findings pave the way for the development of topological antiferromagnetic spintronics.

关键词： spintronics non-collinear antiferromagnetic Weyl semimetals all-electrical switching spin-orbit torques

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混凝土管桩基本性能时效性预测研究

建筑机械 2024年第8期 194-200页

作者：赵红波朱乃江梁仕超丁元寄中冀建勘集团有限公司河北石家庄050227

为高精度获得混凝土管桩在时间尺度上的时效性预测模型,文章基于混凝土管桩的承载力、位移和距离混凝土表面的氯离子浓度共3种基本性能时间序列数据,以极限学习机模型(ELM)为基础,基于改进哈里斯鹰算法(MHHO)、改进麻雀搜索算法(MSSA)... 详细信息

为高精度获得混凝土管桩在时间尺度上的时效性预测模型,文章基于混凝土管桩的承载力、位移和距离混凝土表面的氯离子浓度共3种基本性能时间序列数据,以极限学习机模型(ELM)为基础,基于改进哈里斯鹰算法(MHHO)、改进麻雀搜索算法(MSSA)、改进鹈鹕算法(MPOA)构建管桩基本效能高精度预测模型。结果表明:在模拟管桩承载力、位移和氯离子浓度3种指标时,不同模型模拟值均表现出相同的时间变化趋势。其中MHHO-ELM模型变化趋势与实测值最为接近,同时MHHOELM模型模拟值的一致性最高、误差最低,在所有模型中精度最高,可推荐作为管桩基本性能的时效性模型使用。

关键词：混凝土管桩基本性能时效性预测极限学习机哈里斯鹰算法

基于网络文本分析的旅游形象感知研究——以长沙为例

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白城师范学院学报 2024年第2期38卷 82-89,100页

作者：赵金金孙玉梅姜乃源徐凤丹王玉婕淮北师范大学历史文化旅游学院安徽淮北235065 白城师范学院旅游与地理科学学院吉林白城137000 东北财经大学旅游与酒店管理学院辽宁大连116025

目的地旅游形象关乎目的地吸引力及游客的选择,而准确地了解游客的旅游目的地形象感知,是有效提升旅游目的地形象的基础.以7个网站中2019—2020年游客视角下发表的242篇网络游记作为数据来源,利用网络文本分析法对长沙旅游形象感知进行... 详细信息

目的地旅游形象关乎目的地吸引力及游客的选择,而准确地了解游客的旅游目的地形象感知,是有效提升旅游目的地形象的基础.以7个网站中2019—2020年游客视角下发表的242篇网络游记作为数据来源,利用网络文本分析法对长沙旅游形象感知进行了研究.结果表明:(1)长沙旅游形象可分为知名建筑和旅游景点、美味特色小吃、独特人文氛围和旅游体验三大主题;(2)橘子洲、臭豆腐、岳麓山、美食、茶颜悦色、太平街等对旅游者的吸引力较大;(3)旅游者对旅游吸引物、旅游设施和服务的感知较为深刻,而对旅游环境和氛围感知仍不足;(4)旅游者对长沙情感形象的积极、消极和中性情绪占比分别为64.78%、11.57%和23.65%,长沙仍存在不能给旅游者带来深刻体验感的问题.据此,提出长沙旅游形象提升策略,以促进长沙旅游业高质量发展.

关键词：旅游形象感知网络文本分析长沙

Electrochemical reconstruction: a new perspective on Sn metal-organic complex microbelts as robust anode for lithium storage

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Rare Metals 2024年第1期43卷 76-86页

作者： Jin-Ke Shen nai-Teng Wu Li-Yuan Wang Gang jiang Dong-Lei Guo Jin Li Gui-Long Liu Hong-Yu Mi Huan Pang Xian-Ming Liu Key Laboratory of Function-oriented Porous Materials of Henan Province College of Chemistry and Chemical EngineeringLuoyang Normal UniversityLuoyang 471934China State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources School of Chemical Engineering and TechnologyXinjiang UniversityUrumqi 830046China School of Chemistry and Chemical Engineering Institute for Innovative Materials and EnergyYangzhou UniversityYangzhou 225009JiangsuChina

Tin-based materials with high theoretical capacity and suitable working voltage are ideal anode materials for lithium-ion batteries(LIBs). However, to overcome their shortcomings(volume expansion and inferior stability), the preparation processes are usually complicated and expensive. Herein, a tin-based metal-organic complex(tin 1,2-benzenedicarboxylic acid, Sn-BDC)with one-dimensional microbelt morphology is synthesized by a facile, rapid and low-cost co-precipitation method, and served as anode material for LIBs without any post-treatment. Sn-BDC exhibits a high reversible capacity with609/440 m Ah·g^(-1) at 50/2000 m A·g^(-1), and robust cycling stability of 856 m Ah·g^(-1) after 200 cycles at 200 m A·g^(-1),which are obviously superior to that of the Sn Ox/C counterparts. Moreover, an electrochemical reconstruction perspective on the lithium storage mechanism of Sn-BDC is proposed by systematic ex-situ characterizations. The reconstructed SnO_(2) replaces Sn-BDC and becomes the active material in the subsequent cycles. As the by-product of the lithiation reaction, the formed Li-based metal-organic complex(Li-BDC, wrapped around the reconstructed SnO_(2)) plays an important role in alleviating volume expansion and accelerating the charge transfer *** work is beneficial to design and construct the new electrode materials based on the electrochemical reconstruction for advanced LIBs.

关键词： Electrochemical reconstruction Metal-organic complex Anode Lithium storage mechanism Lithium-ion batteries

Dissipation and residue of ethephon in maize field

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Journal of Integrative Agriculture 2015年第1期14卷 106-113页

作者： DONG Jian-nan MA Yong-qiang LIU Feng-mao jiang nai-wen JIAN Qiu Department of Applied Chemistry College of ScienceChina Agricultural University Institute for the Control of Agrochemicals Ministry of Agriculture

A rapid and reliable method was developed for analysis of ethephon residues in maize, in combination with the investigation of its dissipation in field condition and stabilities during the sample storage. The residue analytical method in maize plant, maize kernel and soil was developed based on the quantification of ethylene produced from the derivatization of ethephon residue by adding the saturated potassium hydroxide solution to the sample. The determination was carried out by using the head space gas chromatography with flame ionization detector （HS-GC-FID）. The limit of quantification （LOQ） of the method for maize plant was 0.05, 0.02 mg kg-1 for maize kernel and 0.05 mg kg-1 for soil, respectively. The fortified recoveries of the method were from 84.6-102.6%, with relative standard deviations of 7.9-3.8%. Using the methods, the dissipation of ephethon in maize plant or soil was investigated. The half life of ethephon degradation was from 0.6 to 3.3 d for plant and 0.7 to 5.7 d for soil, respectively. The storage stabilities of ethephon residues were determined in fresh and dry kernels with homogenization and without homogenization process. And the result showed that ethephon residues in maize kernels were stable under-18℃ for 6 mon. The results were helpful to monitor the residue dissipation of ethephon in the maize ecosystem for further ecological risk assessment.

关键词： ethephon residue maize degradation storage stability

CT angiography of pulmonary embolism using a 64 slice multi-detector scanner

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Chinese Medical Journal 2009年第20期122卷 2509-2515页

作者： QIN nai-shan jiang Xue-xiang QIU Jian-xing ZHU Ying WANG Ji-chen Department of Radiology Peking University First Hospital Beijing 100034 China

Background Multi-detector computed tomography （MDCT） has already been the first line investigation method for diagnosis of pulmonary embolism （PE）. Reducing the amount of contrast medium used during CT scanning could decrease the incidental rate of adverse reactions. Our study amied to evaluate the image quality of pulmonary arteries using 64 slice multi-detector CT with small volumes of contrast media injection. Methods Forty nonconsecutive patients without PE or other lung diseases were randomly assigned to two groups. Group A underwent CT scanning with 16×1 .25 mm collimation and a 70 ml contrast injection, while group B had CT with 64×0.625 mm collimation and 20 ml of contrast injection. Two readers independently depicted the segmental and subsegmental pulmonary arteries. Reasons we could not analyze the pulmonary artery or that led to misdiagnosis of pulmonary embolism were evaluated, including the degree of contrast enhancement of the main pulmonary artery, and factors that caused misdiagnosis of PE （flow-related artifacts, partial volume artifact, beam-hardening artifacts and enhancement of pulmonary vein）. The independent samples t-test, Mann-Whitney U test and Pearson chi-square test were applied. Results There were no significant differences in image quality of segmental and subsegmental arteries between the two groups. No significant difference was found for factors that made pulmonary arteries non-analyzable or in the misdiagnosis of PE, except the degree of contrast enhancement. Conclusion 64×0.625 mm collimation with 20 ml contrast injection could depict the pulmonary arteries well.

关键词： computed tomographic pulmonary angiography pulmonary embolism pulmonary arteries contrast media

Comparing a novel Catfish flow restoration device and the Solitaire stent retriever for thrombectomy revascularisation in emergent largevessel occlusion stroke:a prospective randomised controlled study

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Stroke & Vascular Neurology 2023年第6期8卷 435-443页

作者： Gang Luo Xiaoyan Yan Guodong Xiao Liping Wei Ya li kun nai bi jiang Rongyao Ma Wenhuo Chen Chun Fang Zhiming Zhou Jieqing Wan Ya Peng Guilian Zhang Junfeng Zhao Li Li Haicheng Yuan Jin Wu Bing Li Fan Zhang Yuhong Cheng Feng Gao Zhongrong Miao Department of Intervention Interventional Neuroradiology CenterBeijing Tiantan HospitalCapital Medical UniversityBeijingChina Department of Intervention Interventional Neuroradiology CenterChina National Clinical Research Center for Neurological DiseasesBeijingChina Biostatistics Peking University Clinical Research InstituteBeijingChina Neurology The Second Affiliated Hospital of Suzhou UniversityJiangsuChina Department of Neurology Luoyang Central Hospital Affiliated to Zhengzhou UniversityLuoyangHenanChina Neurosurgery Hotan District People's HospitalHotanChina Neurology Nanshi Hospital of NanyangNanyangChina Neurology Zhangzhou Municipal Hospital of Fujian Province and Zhangzhou Affiliated Hospital of Fujian Medical UniversityZhangzhouFujianChina Department of Intervention Tongji Hospital Affiliated to Tongji UniversityShanghaiShanghaiChina Department of Intervention The First Affiliated Hospital of Wannan Medical CollegeWuhuAnhuiChina Department of Neurosurgery Shanghai Jiao Tong University School of Medicine Affiliated Renji HospitalShanghaiChina Department of Neurosurgery Changzhou No.1 People's HospitalChangzhouChina Neurology The Second Affiliated Hospital of Xi'an Jiaotong UniversityXi'anChina Neurology Siping Central People’s HospitalSipingChina Department of Intervention Xijing Hospital of Air Force Military Medical UniversityXi'anChina Neurology Qingdao Central Medical GroupQingdaoChina Neurology The Second Affiliated Hospital of Nanjing Medical UniversityNanjingChina Department of Intervention Qindao University Medical College Affiliated Yantai Yuhuangding HospitalYantaiShandongChina Neurology Hainan General Hospital/Hainan Affiliated Hospital of Hainan Medical UniversityHainanChina Department of Intervention Linfen Central HospitalLinfenShanxiChina

Background The Catfish stent retriever is a newly developed mechanical thrombectomy device for rapid recanalisation in emergent large vessel occlusion(ELVO)*** current trial aimed to assess whether the Catfish stent retriever is non-inferior to the Solitaire stent retriever in terms of outcomes in ELVO *** This was a randomised,prospective,parallel-group,multicentre,open-label,non-inferiority study conducted at 18 sites in *** primary outcome was the proportion of cases with successful recanalisation(modified thrombolysis in cerebral infarction score of 2b or 3)following the *** efficacy outcomes included the National Institutes of Health Stroke Scale scores at 24 hours and 7 days or discharge if earlier,time from artery puncture to successful recanalisation and good clinical outcome(modified Rankin scale score≤2)at 90 *** outcomes included symptomatic intracranial haemorrhage,all cause-death and severe adverse events at 90 *** Between 3 March 2019 and 5 June 2021,118 and 120 patients were randomly allocated to the Catfish and Solitaire groups,*** primary endpoint after all endovascular procedures was non-inferior in the Catfish group(88.5%,100/113)than in the Solitaire group(87.7%,100/114),with a rate difference(RD)of 0.78%(95%CI-7.64 to-9.20;p=0.001).Sensitivity analysis only considering the per-protocol set also yielded similar results,with an RD of 0.83%(95%CI-7.03 to-8.70;p<0.001).Additionally,the proportions of cases with good clinical outcomes(47.8%vs 50.0%,p=0.739)and all-cause death rates(17.7%vs 18.8%,p=0.700)were similar in both groups at 90 *** The Catfish stent retriever is an effective and safe device for endovascular recanalisation in ELVO stroke..

关键词： Solitaire prospective throm

外部风险对粮食种植类家庭农场规模选择的影响研究

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经济问题 2022年第4期 85-92页

作者：陈五湖蒋乃华扬州大学农学院江苏扬州225009 扬州建工控股有限责任公司江苏扬州225009 南通大学江苏南通226019

家庭农场是新时代乡村产业振兴的有生力量,是现代农业经营体系的重要支撑,其在农业适度规模经营实践中面临着较为严重的风险挑战,极大地影响了家庭农场的健康发展,如何科学指导家庭农场进行规模选择、产业定位和风险防范是基层政府、农... 详细信息

家庭农场是新时代乡村产业振兴的有生力量,是现代农业经营体系的重要支撑,其在农业适度规模经营实践中面临着较为严重的风险挑战,极大地影响了家庭农场的健康发展,如何科学指导家庭农场进行规模选择、产业定位和风险防范是基层政府、农业专家和理论研究面临的重要课题。在建立外部风险对粮食种植类家庭农场规模选择影响分析框架和研究假说的基础上,观测了45个乡镇粮食种植类家庭农场平均规模连续6年的变化情况,测量了自然风险、价格风险、政策风险和社会风险水平,实证分析了四种外部风险对家庭农场经营规模选择的影响。研究发现:自然风险、价格风险、政策风险对粮食种植类家庭农场规模选择有显著的负向抑制效应,且自然风险影响最大,政策风险和价格风险影响逐步次之;社会风险影响不显著。

关键词：粮食种植家庭农场外部风险规模选择