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A Dipolar Cyclization/Fragmentation Strategy for the Catalytic Asymmetric Synthesis of Chiral Eight-Membered Lactams

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CCS Chemistry 2022年第8期4卷 2620-2629页

作者： Mao-Mao Zhang Peng Chen wei xiong Xin-Shang Hui Liang-Qiu Lu Wen-Jing Xiao CCNU-uOttawa Joint Research Centre Key Laboratory of Pesticide and Chemical BiologyMinistry of EducationCollege of ChemistryCentral China Normal UniversityWuhan 430079 State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics(LICP)Chinese Academy of SciencesLanzhou 730000 State Key Laboratory of Applied Organic Chemistry Department of ChemistryLanzhou UniversityLanzhou 730000

Medium-sized nitrogen heterocycles,including eightmembered lactams,are important in synthetic and pharmaceutical chemistry because of their presence in a variety of natural products and drug molecules.Previous attempts at synthesis using a direct headto-tail cyclization strategy suffered from competitive self-cyclization and oligomerization of dipolar species.Herein,we propose an alternative strategy.

关键词： asymmetric catalysis dipolar cyclization fragmentation eight-membered lactams

Effect of nickel oxide morphology on the nitrogen electrochemical reduction reaction

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Nano Materials Science 2020年第4期2卷 353-359页

作者： Ping Zhang wei xiong Min Zhou School of Chemistry and Environmental Engineering Key Laboratory for Green Chemical Process(Ministry of Education)Hubei Key Lab of Novel Reactor&Green Chemical TechnologyWuhan Institute of TechnologyLiufang Road 1Wuhan430205China

In order to study the effect of catalysts’morphology on the electrochemical reduction of nitrogen gas,sample catalysts of NiO with four different morphologies(hollow spherical,sea urchin-shape,cubic block,and rod-like)were prepared.Characterization of the NiO catalysts was carried out using SEM,BET,XRD and electrochemical investigation techniques.The results indicated that the nitrogen reduction reaction(NRR)is strictly dependent on the morphology of the NiO catalysts,as the hollow spherical NiO showed the best electrochemical NRR performance of NH3 yield rate(3.21μg h^-1 mg^-1 cat.,4.1910^-11 mol cm^-2 s^-1)and Faradaic efficiency(1.37%),which was higher than the yields and efficiencies of the rod-NiO(1.8μg h^-1 mg^-1 cat.,3.2410^-11 mol cm^-2 s^-1,1.17%),sea urchin-NiO(1.66μg h^-1 mg^-1 cat.,2.4410^-11 mol cm^-2 s^-1,1.08%)and cubic block-NiO(1.32μg h^-1 mg^-1 cat.,2.1410^-11 mol cm^-2 s^-1,0.81%),respectively.These results match the order of the specific surface area of the NiO samples,with hollow spherical(113.91 m^2 g^-1)>rod-NiO(55.12 m^2 g^-1)sea urchin-NiO(55.29 m^2 g^-1)>cubic block-NiO(38.57 m^2 g^-1).This correlation can be attributed to the fact that large specific surface areas can provide more active sites for electrocatalysis.This work demonstrates the effect of the morphology of the NiO catalysts on its electrochemical NRR properties,which could offer some opportunity for the preparation of new electrode materials with improved electrocatalytic properties.

关键词： Nickel oxide Morphology structure Electrocatalytic N2 reduction

Laparoscopic umbilical trocar port site endometriosis:A case report

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World Journal of Clinical Cases 2020年第8期8卷 1532-1537页

作者： Xue Ao wei xiong Shi-Qiao Tan Department of Obstetrics and Gynecology West China Second University HospitalKey Laboratory of Birth Defects and Related Diseases of Women and Children(Sichuan University)Ministry of EducationChengdu 610041Sichuan ProvinceChina

BACKGROUND Abdominal wall endometriosis can occur secondary to gynecological and obstetric pelvic laparotomy;however,this is a rare clinical event.There are few cases of endometriosis involving the incision site of a laparoscopic surgery,especially for those of the endometrial nodule at the umbilical trocar port site where the camera is placed.CASE SUMMARY We describe the case of a 37-year-old woman who presented with a 2-year history of a tough swelling below the umbilicus,which presented periodical pain during menstruation.The patient had undergone laparoscopic ovarian cystectomy 4 years prior,and we theorized that the umbilical nodule was a complication of that laparoscopic surgery.Histological analysis confirmed the diagnosis of abdominal umbilical scar endometriosis secondary to previous laparoscopic surgery.Surgical removal of the nodule followed by three cycles of leuprorelin was curative.CONCLUSION Abdominal mass and pain in women of childbearing age with a previous history of pelvic surgery should support consideration of endometriosis at the surgical site.

关键词： Endometriosis Laparoscopy Abdominal wall Scar endometriosis Ovarian cystectomy Case report

长江流域农业绿色发展水平评价与时空差异分析

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生态经济 2024年第7期40卷 119-128页

作者：熊巍周沛洋华中农业大学经济管理学院湖北武汉430070

对长江流域农业绿色发展水平进行评价与影响因素分析,能促进长江流域农业绿色高质量发展。基于2006—2020年长江流域19个省份的面板数据,从绿色生产、绿色生态、经济效益、生活水平四个维度构建了农业绿色发展水平评价指标体系;并通过... 详细信息

对长江流域农业绿色发展水平进行评价与影响因素分析,能促进长江流域农业绿色高质量发展。基于2006—2020年长江流域19个省份的面板数据,从绿色生产、绿色生态、经济效益、生活水平四个维度构建了农业绿色发展水平评价指标体系;并通过熵权法对各省份农业绿色发展水平进行测度;最后应用区域差异分析法、空间自相关性分析对区域内与区域间的时空发展差异、关联度进行探讨。结果表明:(1)长江流域农业绿色发展水平整体呈现出稳步上升趋势,干流发展趋势优于支流。(2)长江流域农业绿色发展水平区域差异呈现出波动扩大的变化趋势。(3)长江流域各省份农业绿色发展水平显示出空间聚集效应,其中上海、江苏、浙江是高—高聚集模式,重庆、贵州、广西是低—低聚集模式。因此,要提高长江流域农业绿色发展水平,各省份应制定个性化政策、重视并补齐发展短板、加强区域间辐射效应。

关键词：农业绿色发展长江流域指标体系空间自相关时空差异

Pathway for high-energy density LiMnFePO4 cathodes

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Progress in Natural Science:Materials International 2023年第1期33卷 126-131页

作者： Shaoluan Huang Wenzhong Lin Liewu Li Pei Liu Tao Huang Zhencheng Huang Jinli kong wei xiong Wenwei Yu Shenghua Ye Jiangtao Hu Qianling Zhang Jianhong Liu Graphene Composite Research Center College of Chemistry and Environmental Engineering Shenzhen University Shenzhen Eigen–Equation Graphene Technology Co.Ltd.

Polyanion cathodes are credited for its thermal stability and better safety, no matter in lithium ion batteries or sodium ion batteries. Polyanion oxides with phosphate groups came to the public’s attention in 1997, and the representative material is LiFePO4, which has been widely applied and plays a huge role in the field of powder batteries and energy storage system. However, owing to the low lithiation potentials and storage sites, the energy densities of polyanion cathodes have been restricted, resulting of low-endurance and limited application scenarios. Accordingly, here, we use cheap and environmental friendly raw materials as precursors to synthesis high energy density LiMn0.6Fe0.4PO4@C cathode by a simple spray-drying and high temperature calcination process.The self-designed liquid polyacrylonitrile(LPAN) is added for the intention of nanoparticle coating, conductive network construction and particle granulation. The low-cost and carbon-coated LiMn0.6Fe0.4PO4cathode exhibits excellent reversible capacity, low electrochemical polarization and excellent rate capacity, which maintains93.5% capacity retention after cycling 1000 times at 5C. The work introduces a new avenue to fabricate olivine structure cathodes with outstanding electrochemical performance for the high energy density lithium ion batteries.

关键词： Polyanion cathode Liquid polyacrylonitrile Cost effective High energy density High stability

Orbital decompression surgery and horse chestnut seed extract improved superior orbital vein blood flow in patients with thyroid-associated ophthalmopathy

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International Journal of Ophthalmology(English edition) 2016年第6期9卷 869-875页

作者： Yu-Jie Wu Xin wei Man-Yi Xiao wei xiong Department of Ophthalmology and Eye Disease Research Center the Second Xiangya Hospital of Central South UniversityChangsha 410011Hunan PUniversityChangsha 410011Hunan ProvinceChinarovinceChina

AIM： To evaluate the efficacy and safety of orbital decomposition （OD） surgery in combination with horse chestnut seed extract （HCSE）, as compared to OD atone, in patients with thyroid-associated ophthalmopathy （TAO）. METHODS： Sixty-two orbits from 62 TAO patients were randomly assigned to OD or OD＋HCSE at 1：1 ratio （31 received OD alone, 31 received OD ＋HCSE）. Forty-two orbits from 21 healthy subjects were used as controls. Complete ophthalmic examination and color Doppler flow imaging （CDFI） were performed before surgery and 3mo post-surgery on all 62 orbits from the TAO patients. CDFI were also performed on the 42 control orbits, The effect of OD ＋HCSE and OD alone on TAO orbits was compared on several endpoints, including superior ophthalmic vein blood flow （SOVBF） parameters, subjective assessment, soft tissue involvement, lid retraction, diplopia, eye movement restriction, degree of exophthalmos, and intraocular pressure. The control orbits were used as reference for the SOVBF parameters. RESULTS： OD surgery with or without HCSE improved SOVBF, symptoms and soft tissue involvement, decreased degree of exophthalmos and intraocular pressure in orbits of TAO patients. The OD ＋HCSE combination led to significantly better improvement of SOVBF than OD alone. The differences between the reductions of SOVBF in the two groups are 1.26 cmls in max-volecity and 0.52 cm/s in min-voiecity （P〈0.0001）. CONCLUSION： SOVBF is significantly reduced in the orbits affected with TAO, indicating that congestion may be an important factor contributing to TAO pathogenesis. OD surgery improves the SOVBF, and combination of HCSE medication and OD surgery further improved venous return than OD surgery alone.

关键词： thyroid-associated ophthalmopathy colorDoppler flow imaging superior orbital vein orbitaldecompression horse chestnut seed extract

The status and development proposal of carbon sources and sinks monitoring satellite system

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碳中和(英文)

碳中和(英文) 2022年第1期1卷 153-170页

作者： Guang Meng Yuan Wen Miaomiao Zhang Yilei Gu wei xiong Zijun Wang Shengda Niu Shanghai Academy of Spaceflight Technology ShanghaiChina Shanghai Jiao Tong University ShanghaiChina Shanghai Institute of Satellite Engineering ShanghaiChina Anhui Institute of Optical Fine Mechanics HefeiChina

In order to mitigate global warming,the international communities actively explore low-carbon and green development methods.According to the Paris Agreement that came into effect in 2016,there will be a global stocktaking plan to carry out every 5 years from 2023 onwards.In September 2020,China proposed a"double carbon"target of carbon peaking before 2030 and carbon neutrality before 2060.Achieving carbon peaking and carbon neutrality goals requires accurate carbon emissions and carbon absorptions.China’s existing carbon monitoring methods have insufficient detection accuracy,low spatial resolution,and narrow swath,which are difficult to meet the monitoring requirement of carbon sources and sinks monitoring.In order to meet the needs of carbon stocktaking and support the monitoring and supervision of carbon sources and sinks,it is recommended to make full use of the foundation of the existing satellites,improve the detection technical specifications of carbon sources and sinks monitoring measures,and build a multi-means and comprehensive,LEO-GEO orbit carbon monitoring satellite system to achieve higher precision,higher resolution and multi-dimensional carbon monitoring.On this basis,it is recommended to strengthen international cooperation,improve data sharing policy,actively participate in the development of carbon retrieval algorithm and the setting of international carbon monitoring standards,establish an independent and controllable global carbon monitoring and evaluation system,and contribute China’s strength to the global realization of carbon peaking and carbon neutrality.

关键词： Carbon sources and sinks Greenhouse gases Carbon monitoring system Carbon neutrality Carbon stocktaking

Current status and cause analysis of microplastic pollution in sea areas in China

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China Geology 2022年第1期5卷 160-170页

作者： wei xiong Xi Mei Bei-bei Mi Hao Yang Zong-zhu Han Yong Zhang Wen-chao Lu Qingdao Institute of Marine Geology China Geological SurveyMinistry of Natural ResourcesQingdao 266071China College of Marine Geosciences Ocean University of ChinaQingdao 266100China State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences(Wuhan)Wuhan 430074China China Geological Survey Ministry of Natural ResourcesBeijing 100037China

As a new type of pollutants in the marine environment,microplastics have attracted increasing attention from scientific researchers and environmental protection workers in China and abroad.However,for the microplastic pollution in sea areas in China,there are a very limited number of studies on its current status and few reviews of research on the microplastics.This paper reviews the surveys and researches of microplastics in the Bohai Sea,the Yellow Sea,the East China Sea,the South China Sea,and main estuaries in China carried out in recent years and proposes an outlook for future work,aiming to provide research suggestions and solutions for ecological protection against microplastic pollution in sea areas in China.Previous studies have shown that microplastics are widely distributed in water bodies and sediments in sea areas and major estuaries in China.The Pearl River Estuary,in the South China Sea suffers the most serious microplastic pollution,followed by the Bohai Sea.In contrast,the microplastic pollution in the Yellow Sea and the East China Sea is comparatively slight.Microplastics in sea areas in China are mainly fibrous and are concentrated in offshore areas with developed industry and a dense population(especially around estuaries and bays).In addition,they are widely affected by human activities,such as shipping,aquaculture,industry,and sewage discharge.Here the authors suggest unifying measurement units and research methods and developing related standard systems to carry out researches related to microplastics.Furthermore,this paper also suggests further deepening researches on both the source-sink process of microplastics and nanoscale microplastics while enhancing the development and implementation of related policies,aiming to promote researches and control of microplastics in sea areas in China.

关键词： Microplastic Marine pollution Distribution pattern Environmental geological survey engineering Bohai Sea Yellow Sea East China Sea South China Sea

生态环境损害赔偿金纳入政府非税收入的正当性

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中南民族大学学报（人文社会科学版） 2024年第3期44卷 113-121,186页

作者：熊伟曹保磊武汉大学法学院湖北武汉430072

生态环境损害赔偿金纳入政府非税收入,不应局限于解决生态环境损害赔偿金的预算列支问题,还应考虑生态环境损害救济规则的变动,以避免法秩序内部的矛盾。《生态环境损害赔偿制度改革方案》中政府主导的生态环境损害替代修复机制不同于... 详细信息

生态环境损害赔偿金纳入政府非税收入,不应局限于解决生态环境损害赔偿金的预算列支问题,还应考虑生态环境损害救济规则的变动,以避免法秩序内部的矛盾。《生态环境损害赔偿制度改革方案》中政府主导的生态环境损害替代修复机制不同于《民法典》确立的生态环境损害私法救济规则。在公共财产权体系下,建立政府与生态环境损害致害者之间的报偿关系,可以弥补生态环境损害赔偿金纳入政府非税收入正当性之不足。生态环境损害赔偿金作为受损生态环境损害的修复资金,应当作为政府非税收入中的“社会公共财产收入”,列入我国公共财产权体系,参照政府性基金预算进行支出管理。

关键词：生态环境损害赔偿金政府非税收入公共财产权