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Palladium-catalyzed multi components oxy-aminofluorination and aminofluorination of gem-difluoroalkenes

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Chinese Chemical Letters 2024年第2期35卷 420-425页

作者： Fen Wu Xin Li Junbiao Chang Dachang Bai State Key Laboratory of Antiviral Drugs NMPA Key Laboratory for Research and Evaluation of Innovative DrugKey Laboratory of Green Chemical Media and ReactionsMinistry of EducationSchool of Chemistry and Chemical EngineeringPingyuan LaboratoryHenan Normal UniversityXinxiang 453007China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Organofluorine compounds are widely used in the realm of drug discovery and material ***,we developed palladium catalyzed intermolecular aminofluorination and oxy-aminofluorination of gem‑difluoroalkenes with N-fluorobenzenesulfonimide(NFSI),in which NFSI was used as the nitrogen source and *** reaction provides an efficient and straightforward synthesis route of a series ofα-trifluoromethyl benzylic ***,three/four components oxy-aminofluorination processes were realized to giveα-trifluoromethyl benzylic ether with a terminal amino group,which proceed through C(sp^(3))-O bond cleavage of easily available ether and simultaneous introduced a fluorine,an amino and an oxy substituent in one pot with excellent *** divergent reactivity not only included the incorporation of one ether molecular,but also much more challenged two ether insertion with excellent selectivity through succession C(sp^(3))-O bonds *** protocol allows for concise synthesis of high value amines with fluoroalkyl-substituents and selectively transformation of easily available ethers by high-valent palladium catalysis.

关键词： Palladium Multi components Aminofluorination Oxy-aminofluorination C(sp^(3))-O bond cleavage

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室内模拟戈壁地表降雨对风蚀过程的影响

Journal of Geographical Sciences 2024年第3期34卷 610-630页

作者：孙莉英王春辉段光耀 Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchCASBeijing100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049China Beijing Water Science and Technology institute Beijing100048China

In the present study,indoor experiments were carried out to investigate the effects of rainfall on subsequent wind erosion processes on the simulated Gobi surface,with soils and gravels collected from the Alax Gobi in northwestern *** results showed that the wind erosion rate(WR)ranged from 0.4 to 1931.2 g m^((-2)min^((-1)and that the sediment transportation rate(STR)ranged from 0.00 to 51.47 g m^((-2)s^((-1)under different gravel coverage conditions(0%,20%,40%and 60%)when the wind velocity changed from 6 m s^((-1)to 18 m s^((-1).Both WR and STR increased with increasing wind velocity as a power function and decreased with increasing gravel *** rainfall event had significant inhibitory effects on WR and STR,and the complex effects of soil crust formation and the changing soil surface roughness(SSR)by rainfall event played significant roles in reducing these rates during subsequent wind *** this study,a valuable exploration of the effects of rainfall events on subsequent wind erosion processes in the Gobi area was *** findings are of great significance for a better understanding and effective prediction of dust emissions in this region.

关键词： inhibitory effects wind erosion rate sediment transportation rate gravel coverage indoor simulation experiment

One-step cell biomanufacturing platform:porous gelatin microcarrier beads promote human embryonic stem cell-derived midbrain dopaminergic progenitor cell differentiation in vitro and survival after transplantation in vivo

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Neural Regeneration research 2024年第2期19卷 458-464页

作者： Lin Feng Da Li Yao Tian Chengshun Zhao Yun Sun Xiaolong Kou Jun Wu Liu Wang Qi Gu Wei Li Jie Hao Baoyang Hu Yukai Wang State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijingChina institute for Stem Cell and Regenerative Medicine Chinese Academy of SciencesBeijingChina National Stem Cell Resource Center Chinese Academy of SciencesBeijingChina Savaid Medical School University of Chinese Academy of SciencesBeijingChina Beijing institute for Stem Cell and Regenerative Medicine BeijingChina State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijingChina

Numerous studies have shown that cell replacement therapy can replenish lost cells and rebuild neural circuitry in animal models of Parkinson’s *** of midbrain dopaminergic progenitor cells is a promising treatment for Parkinson’s ***,transplanted cells can be injured by mechanical damage during handling and by changes in the transplantation ***,we developed a one-step biomanufacturing platform that uses small-aperture gelatin microcarriers to produce beads carrying midbrain dopaminergic progenitor *** beads allow midbrain dopaminergic progenitor cell differentiation and cryopreservation without digestion,effectively maintaining axonal integrity in ***,midbrain dopaminergic progenitor cell bead grafts showed increased survival and only mild immunoreactivity in vivo compared with suspended midbrain dopaminergic progenitor cell ***,our findings show that these midbrain dopaminergic progenitor cell beads enhance the effectiveness of neuronal cell transplantation.

关键词： axonal integrity cell cryopreservation cellular environment cellular niche cell replacement therapy dopaminergic progenitors human pluripotent stem cell mechanical damage neuronal cell delivery Parkinson’s disease small-aperture gelatin microcarriers

Vanadyl Sulfate Based Hole-Transporting Layer Enables Efficient Organic Solar Cells

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Chinese Journal of Chemistry 2024年第14期42卷 1644-1650页

作者： Mengdi Li Yuqing Sun Yang Cheng Chaowei Zhao Jicai Zhang Weiwei Li research Center for Optoelectronic Materials and Devices School of Physical Science and TechnologyGuangxi UniversityNanningGuangxi530004 China institute of Applied Chemistry Jiangxi Academy of SciencesNanchangJiangxi330096 China Beijing Advanced Innovation Center for Soft Matter Science and Engineering&State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing100029 China

It remains an urgent task to develop alternative hole-transporting layer(HTL)materials beyond commonly used PEDOT:PSS to increase the shelf-life of organic solar cells(OSCs).Inorganic metal oxide type materials,such as NiO_(x),CoO_(x)and VO_(x),with suitable work functions have attracted numerous research attention *** this work,more abundant and easily accessible oxygenated salt,vanadyl sulfate(VOSO_(4))has been demonstrated to be excellent choice as HTL for *** VOSO_(4)-based HTL can be readily processed by spin-coating from the precursor solution with subsequent thermal annealing and UVO *** a consequence,a high power conversion efficiency(PCE)of 18.72%can be achieved for PM8:L8-BO based OSCs with the VOSO_(4)-based *** transmittance,smooth film surface,suitable energy level and high conductivity were revealed to contribute to the high OSC *** importantly,compared to device with PEDOT:PSS,VOSO_(4)-based OSCs exhibit improved stability when stored in the N_(2)filled glove *** being stored for 600 h,VOSO_(4)-based device can retain 89%of its initial ***,VOSO_(4)can be used as general HTL in PM6:BTP-BO-4Cl and PM6:IT-4F based OSCs,yielding high PCEs of 17.87%and 13.85%,respectively.

关键词： Organic solar cells Semiconductors Hole-transporting layers Vanadyl sulfate Power output Efficiency Vanadium Interfacial modification

Selection of media tools for community planning:A study from the perspective of communicative planning

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Chinese Journal of Population,Resources and Environment 2024年第3期22卷 305-311页

作者： Xiaotong Zhang Linjun Yu Yang Li China Architecture Design&research Group Beijing 100044China China National Engineering research Center for Human Settlements Beijing 100044China Chinese Society for Sustainable Development Beijing 100038China Aerospace Information research institute Chinese Academy of SciencesBeijing 100094China

In community planning,due to the lack of evidence regarding the selection of media tools,this study examines how a common but differentiated ideal speech situation can be created as well as how more appropriate media tools can be defined and selected in the community planning ***,this study describes the concept and theoretical basis of media used in community planning from the perspectives of the multiple effects of media evolution on communicative ***,the classification criteria and typical characteristics of media tools used to support community planning are clarified from three dimensions:acceptability,cost effectiveness,and ***,strategies for applying media tools in the four phases of communicative planning-namely,state analysis,problem identification,contradictory solution and optimization-are ***,trends in the development of media tools for community planning are explored in terms of multistakeholder engagement,supporting scientific decision-making and multiple-type media *** results provide a reference for developing more inclusive,effective,and appropriate media tools for enhancing decision-making capacity and modernizing governance in community planning and policy-making processes.

关键词： Community planning Media tools Communicative planning

Automatic Finding of Brain-Tumour Group Using CNN Segmentation and Moth-Flame-Algorithm,Selected Deep and Handcrafted Features

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Computers, Materials & Continua 2024年第5期79卷 2585-2608页

作者： Imad Saud Al Naimi Syed Alwee Aljunid Syed Junid Muhammad lmran Ahmad K.Suresh Manic Faculty of Electronic Engineering Technology University Malaysia Perils(UniMAP)Pauh Putra CampusArauPerlis02600Malaysia Department of Electrical and Communication Engineering National University of Science and TechnologyAL HailAL Seeb130Sultanate of Oman Department of research and Innovation Saveetha School of EngineeringSaveetha Institute of Medical and Technical Sciences(SIMATS)ChennaiTamiNadu602105India

Augmentation of abnormal cells in the brain causes brain tumor(BT),and early screening and treatmentwill reduce its harshness in ***’s clinical level screening is usually performed with Magnetic Resonance Imaging(MRI)due to its multi-modality *** overall aims of the study is to introduce,test and verify an advanced image processing technique with algorithms to automatically extract tumour sections from brain MRI scans,facilitating improved *** research intends to devise a reliable framework for detecting the BT region in the twodimensional(2D)MRI slice,and identifying its class with improved *** methodology for the devised framework comprises the phases of:(i)Collection and resizing of images,(ii)Implementation and Segmentation of Convolutional Neural Network(CNN),(iii)Deep feature extraction,(iv)Handcrafted feature extraction,(v)Moth-Flame-Algorithm(MFA)supported feature reduction,and(vi)Performance *** study utilized clinical-grade brain MRI of BRATS and TCIA datasets for the *** framework segments detected the glioma(low/high grade)and glioblastoma class *** work helped to get a segmentation accuracy of over 98%with VGG-UNet and a classification accuracy of over 98%with the VGG16 *** study has confirmed that the implemented framework is very efficient in detecting the BT in MRI slices with/without the skull section.

关键词： Brain tumour VGG-UNet VGG16 moth-flame-algorithm classification

Inflection Point Age in the Middle and Older Women—Jiangxi Province,China,2020-2022

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China CDC weekly 2024年第9期6卷 162-167页

作者： Shanlan Yang Langlang Zhang Helang Huang Jiaofeng Wang Lei Wu Zhijun Bao Shanghai institute of Infectious Disease and Biosecurity Fudan UniversityShanghaiChina Department of Gerontology Huadong Hospital Affiliated to Fudan UniversityShanghai Key Laboratory of Clinical Geriatric MedicineResearch Center on Aging and MedicineFudan UniversityShanghaiChina Jiangxi Provincial Key Laboratory of Preventive Medicine School of Public HealthNanchang UniversityNanchang CityJiangxi ProvinceChina

Summary What is already known about this topic?Previous studies have predominantly examined the micro-level aspects of women aging inflection points,while macro-level research using big data on the inflection points o... 详细信息

关键词： Middle Jiangxi currently

Electrochemical Oxygen Evolution Performance of Nitrogen-Doped Ultra-Thin Carbon Nanosheets Composite Ru1Co Single Atom Alloy Catalysts

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Chinese Journal of Chemistry 2024年第9期42卷 973-979页

作者： Ziwei Deng Zhiyi Sun Yaqiong Li Jiajing Pei Wenxing Chen Energy&Catalysis Center Schoolof Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 00049China

Energy transformation is imminent,and hydrogen energy is one of the important new energy *** of the keys to increasing the rate of hydrogen evolution during electrolysis is the use of high-performance catalysts for oxygen evolution reactions(OER).Single-atom alloys(SAAs)have garnered significant attention because they partially reduce costs and combine the advantages of both single-atom catalysts(SACs)and alloy ***,an efficient pyrolysis strategy based on a mixing and drying process is designed to anchor ultra-small Co cluster particles,combined with Ru single atoms dispersed on nitrogen-doped ultra-thin carbon nanosheets(Ru_(1)Co SAA/NC).The prepared electrocatalyst exhibits superior OER activity and superb stability,demonstrating an overpotential of 238 mV for OER with a current density of 10 mA·cm^(-2) in 0.5 mol/L H_(2)SO_(4).And we also utilized in-situ XAS to detect the oxidation state of Ru sites during *** in all,this method achieves cost reductions and efficiency improvements through the design of SAAs,offering new prospects for the structural transformation of clean energy.

关键词： Oxygen evolution reaction Single alloy catalyst Ultra-thin carbon nanosheets Electrocatalyst Pyrolysis RuiCo SAA/NC

NiO@Ni nanoparticles embedded in N-doped carbon for efficient photothermal CO_(2) methanation coupled with H_(2)O splitting

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Nano research 2024年第4期17卷 2283-2290页

作者： Yun Zhou Peng Zheng Fang Wang Fangna Gu Wenqing Xu Qinyang Lu Tingyu Zhu Ziyi Zhong Guangwen Xu Fabing Su institute of Process Engineering Chinese Academy of SciencesBeijing 100190China Key Laboratory on Resources Chemicals and Materials of Ministry of Education Shenyang University of Chemical TechnologyShenyang 110142China institute of Industrial Chemistry and Energy Technology Shenyang University of Chemical TechnologyShenyang 110142China School of Ecology and Environment Beijing Technology and Business UniversityBeijing 100048China Beijing Key Laboratory of Enze Biomass Fine Chemicals College of New Materials and Chemical EngineeringBeijing Institute of Petrochemical TechnologyBeijing 102617China International School of Beijing 10 An Hua Street Shunyi DistrictBeijing 100048China Department of Chemical Engineering Guangdong Technion Israel Institute of Technology(GTIIT)Shantou 515063China Technion Israel institute of Technology(IIT) Haifa32000Israel

Photothermal carbon dioxide(CO_(2))methanation has attracted increasing interest in solar fuel synthesis,which employs the advantages of photocatalytic H_(2)O splitting as a hydrogen source and photothermal catalytic CO_(2) *** work prepared three-dimensional(3D)honeycomb N-doped carbon(NC)loaded with core–shell NiO@Ni nanoparticles generated in situ at 500℃(NiO@Ni/NC-500).Under the photothermal catalysis(200℃,1.5 W/cm^(2)),the CH_(4) evolution rate of NiO@Ni/NC-500 reached 5.5 mmol/(g·h),which is much higher than that of the photocatalysis(0.8 mmol/(g·h))and the thermal catalysis(3.7 mmol/(g·h)).It is found that the generated localized surface plasmon resonance enhances the injection of hot electrons from Ni to NiO,while thermal heating accelerates the thermal motion of radicals,thus generating a strong photo-thermal synergistic effect on the *** CO_(2) reduction to CH_(4) follows the*OCH *** work demonstrates the synergistic effect of NiO@Ni and NC can enhance the catalytic performance of photothermal CO_(2) reduction reaction coupled with water splitting reaction.

关键词： Ni localized surface plasmon resonance photothermal methanation