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Probing atomic-scale structure of dielectric ceramics with scanning transmission electron microscopy

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Journal of Advanced Dielectrics 2024年第3期14卷 1-10页

作者： min Zhang Rui Wei Jinquan Zeng Yuan-Hua lin State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University BeijingP.R.China

High performance dielectric capacitors are ubiquitous components in the modern electronics industry,owing to the highest power density,fastest charge-discharge rates,and long ***,the wide application of dielectric capacitors is limited owing to the low energy *** the past decades,multiscale structures of dielectric ceramics have been extensively explored and many exciting developments have been *** the rapid development of energy storage properties,the atomic structure of dielectric materials is rarely *** this paper,we present a brief overview of how scanning transmission electron microscopy(STEM)is used as a tool to elucidate the morphology,local structure heterogeneity,atomic resolution structure phase evolution and the correlation with energy storage properties,which provides a powerful tool for rational design and synergistic optimization.

关键词： Atomic-scale structure dielectric ceramics STEM energy storage

Engineering singlet and triplet excitons of TADF emitters by different host-guest interactions

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Aggregate 2024年第1期5卷 337-344页

作者： Wei Zhang Jie Kong Rui zhi An Jiachen Zhang Yujie Zhou lin-Song Cui Meng Zhou Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefeiChina Key Laboratory of Precision and Intelligent Chemistry University of Science and Technology of China(USTC)HefeiChina CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefeiChina

Understanding the host-guest interactions for thermally activated delayed fluorescence(TADF)emitters is critical because the interactions between the host matrices and TADF emitters enable precise control on the optoelectronic performance,whereas technologically manipulating the singlet and triplet excitons by using different kinds of host-guest interactions remains ***,we report a comprehensive picture that rationalizes host-guest interaction-modulated exciton recombination by using time-resolved *** found that the early-time relaxation is accelerated in polar polymer because dipole-dipole interaction facilitates the stabilization of the 1CT ***,an opposite trend is observed in longer delay time,and faster decay in the less polar polymer is ascribed to theπ-πinteraction that plays the dominant role in the later stage of the excited *** findings highlight the technological engineering singlet and triplet excitons using different kinds of host-guest interactions based on their electronic characteristics.

关键词： host-guest interaction singlet TADF triplet

Confined Mn^(2+) enables effective aerobic oxidation catalysis

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Science China Chemistry 2024年第5期67卷 1545-1553页

作者： Desheng Yuan Sicong Ma Xiao Kong Chi Zhang lin Chen Chengsheng Yang Lihua Wang Zhen Liu lin Ye Yongmei Liu Rui Ma zhi-Pan Liu Yifeng Zhu Yong Cao Xinhe Bao Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China Department of Chemistry Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsCollaborative Innovation Center of Chemistry for Energy MaterialsFudan UniversityShanghai 200438China Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Institute of Advanced Fluorine-Containing Materials Zhejiang Normal UniversityJinhua 321004China State Key Laboratory of Catalysis National Laboratory for Clean EnergyCollaborative Innovation Center of Chemistry for Energy MaterialsDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Effective and mild activation of O_(2) is essential but challenging for aerobic oxidation. In heterogeneous catalysis, high-valence manganese oxide(e.g., +4) is known to be active for the oxidation, whereas divalent MnO is ineffective due to its limited capacity to supply surface oxygen and its thermodynamically unstable structure when binding O_(2) in reaction conditions. Inspired by natural enzymes that rely on divalent Mn^(2+), we discovered that confining Mn^(2+) onto the Mn_(2)O_(3) surface through a dedicated calcination process creates highly active catalysts for the aerobic oxidation of 5-hydroxymethylfurfural, benzyl alcohol, and *** Mn_(2)O_(3)-confined Mn^(2+) is undercoordinated and efficiently mediates O_(2) activation, resulting in 2–3 orders of magnitude higher activity than Mn_(2)O_(3) alone. Through low-temperature infrared spectroscopy, we distinguished low-content Mn^(2+) sites at Mn_(2)O_(3) surface, which are difficult to be differentiated by X-ray photoelectron spectroscopy. The combination of in-situ energydispersive X-ray absorption spectroscopy and X-ray diffraction further provides insights into the formation of the newly identified active Mn^(2+) sites. By optimizing the calcination step, we were able to increase the catalytic activity threefold *** finding offers promising frontiers for exploring active oxidation catalysts by utilizing the confinement of Mn^(2+)and oftenignored calcination skills.

关键词： confinement catalysis manganese oxide aerobic oxidation divalent Mn^(2+) operando spectroscopies

Expert consensus on the diagnosis, treatment, and prevention of respiratory syncytial virus infections in children

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World Journal of Pediatrics 2024年第1期20卷 11-25页

作者： Xian-Li Zhang Xi Zhang Wang Hua Zheng-De Xie Han-min Liu Hai-lin Zhang Bi-Quan Chen Yuan Chen Xin Sun Yi Xu Sai-Nan Shu Shun-Ying Zhao Yun-Xiao Shang ling Cao Yan-Hui Jia Luo-Na lin Jiong Li Chuang-Li Hao Xiao-Yan Dong Dao-Jiong lin Hong-Mei Xu De-Yu Zhao Mei Zeng zhi-min Chen Li-Su Huang Department of Infectious Disease Children's HospitalZhejiang University School of Medicine3333 Binsheng RoadBinjiang DistrictHangzhou 310052China Clinical Research Unit Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghaiChina Beijing Pediatric Research Institute Beijing Children's HospitalCapital Medical UniversityBeijingChina Department of Pediatric Pulmonology West China Second University HospitalSichuan UniversityChengduChina Department of Pediatric Pulmonology the Second Affiliated Hospital&Yuying Children's HospitalWenzhou Medical UniversityWenzhouChina Department of Infectious Disease Anhui Provincial Children's HospitalHefeiChina Department of Pediatrics the Second Hospital of Hebei Medical UniversityShijiazhuangChina Department of Pediatrics Xijing Hospitalthe Fourth Military Medical UniversityXi'anChina Department of Infectious Disease Guangzhou Women and Children's Medicine CenterGuangzhou Medicine UniversityGuangzhouChina Department of Pediatrics Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina Department of Respiratory Disease Beijing Children's HospitalCapital Medical UniversityBeijingChina Department of Pediatric Respiratory Shengjing Hospital of China Medical UniversityShenyangChina Respiratory Department Children's Hospital Affiliated to Capital Institute of PediatricsBeijingChina Department of Clinical Epidemiology Aarhus UniversityAarhusDenmark Department of Respirology Children's Hospital of Soochow UniversitySuzhouChina Department of Respiratory Children's Hospital of ShanghaiChildren's Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghaiChina Department of Infectious Disease Hainan Women and Children's Medical CenterHaikouChina Department of Infectious Disease Children's Hospital of Chongqing Medical UniversityChongqingChina Department of Respiratory Children's Hospital of Nanjing Medical UniversityNanjingChina Department of Infectious Di

Background Respiratory syncytial virus(RSV)is the leading global cause of respiratory infections and is responsible for about 3 million hospitalizations and more than 100,000 deaths annually in children younger than 5 years,representing a major global healthcare *** is a great unmet need for new agents and universal strategies to prevent RSV infections in early life.A multidisciplinary consensus development group comprising experts in epidemiology,infectious diseases,respiratory medicine,and methodology aims to develop the current consensus to address clinical issues of RSV infections in *** sources The evidence searches and reviews were conducted using electronic databases,including PubMed,Embase,Web of Science,and the Cochrane Library,using variations in terms for"respiratory syncytial virus","RSV","lower respiratory tract infection","bronchiolitis","acute","viral pneumonia","neonatal","infant""children",and"pediatric".Results Evidence-based recommendations regarding diagnosis,treatment,and prevention were proposed with a high degree of *** supportive care remains the cornerstone for the management of RSV infections,new monoclonal antibodies,vaccines,drug therapies,and viral surveillance techniques are being rolled *** This consensus,based on international and national scientific evidence,reinforces the current recommendations and integrates the recent advances for optimal care and prevention of RSV *** improvements in the management of RSV infections will require generating the highest quality of evidence through rigorously designed studies that possess little bias and sufficient capacity to identify clinically meaningful end points.

关键词： Consensus prevention Respiratory syncytial virus Treatment

A lethal mice model of recombinant vesicular stomatitis viruses for EBOV-targeting prophylactic vaccines evaluation

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Virologica Sinica 2024年第3期39卷 516-519页

作者： Hong-Qing Zhang Zhe-Rui Zhang Cheng-lin Deng zhi-ming Yuan Bo Zhang Key Laboratory of Special Pathogens and Biosafety Wuhan Institute of VirologyCenter for Biosafety Mega-ScienceChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China Hubei Jiangxia Laboratory Wuhan430200China

Dear editor,Ebola virus(EBOV)is a member of the genus Orthoebolavirus within the family of ***'s the causative agent of Ebola virus disease(EVD),characterized by general malaise,severe gastrointestinal illness,febrile,coagulopathy,multi-organs dysfunction,and high mortality(up to 90%)in humans and nonhuman primates(NHPs)(Jacob et al.,2020).Since its discovery in 1976,EBOV has grabbed the global concerns,especially after the West African epidemic from 2014 to 2016,which resulted in 30,000 cases and over 11,000 deaths(Feldmann et al.,2020;Jacob et al.,2020).From 2018 to 2022,there have been thousands of infections primarily in the Democratic Republic of the Congo(DRC),resulting in over 2000 *** highlights the importance of continued attention and ongoing surveillance(***/emergenci es/disease-outbreak-news).

关键词： organs mortality editor

Benchmark experiment on slab^(238)U with D-T neutrons for validation of evaluated nuclear data

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Nuclear Science and Techniques 2024年第2期35卷 145-159页

作者： Yan-Yan Ding Yang-Bo Nie Yue Zhang zhi-Jie Hu Qi Zhao Huan-Yu Zhang Kuo-zhi Xu Shi-Yu Zhang Xin-Yi Pan Chang-lin Lan Jie Ren Xi-Chao Ruan Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Institute of Fluid Physics China Academy of Engineering PhysicsMianyang 62100China

A benchmark experiment on^(238)U slab samples was conducted using a deuterium-tritium neutron source at the China Institute of Atomic *** leakage neutron spectra within energy levels of 0.8-16 MeV at 60°and 120°were measured using the time-of-flight *** samples were prepared as rectangular slabs with a 30 cm square base and thicknesses of 3,6,and 9 *** leakage neutron spectra were also calculated using the MCNP-4C program based on the latest evaluated files of^(238)U evaluated neutron data from CENDL-3.2,ENDF/B-Ⅷ.0,JENDL-5.0,and *** on the comparison,the deficiencies and improvements in^(238)U evaluated nuclear data were *** results showed the following.(1)The calculated results for CENDL-3.2 significantly overestimated the measurements in the energy interval of elastic scattering at 60°and 120°.(2)The calculated results of CENDL-3.2 overestimated the measurements in the energy interval of inelastic scattering at 120°.(3)The calculated results for CENDL-3.2 significantly overestimated the measurements in the 3-8.5 MeV energy interval at 60°and 120°.(4)The calculated results with JENDL-5.0 were generally consistent with the measurement results.

关键词： Leakage neutron spectra Uranium D-T neutron source Evaluated nuclear data

Intrahepatic portal venous systems in adult patients with cavernous transformation of portal vein: Imaging features and a new classification

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 481-486页

作者： Xin Huang Qian Lu Yue-Wei Zhang lin Zhang zhi-Zhong Ren Xiao-Wei Yang Ying Liu Rui Tang Hepatopancreatobiliary Center Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China

Background: Cavernous transformation of the portal vein(CTPV) due to portal vein obstruction is a rare vascular anomaly defined as the formation of multiple collateral vessels in the hepatic hilum. This study aimed to investigate the imaging features of intrahepatic portal vein in adult patients with CTPV and establish the relationship between the manifestations of intrahepatic portal vein and the progression of CTPV. Methods: We retrospectively analyzed 14 CTPV patients in Beijing Tsinghua Changgung Hospital. All patients underwent both direct portal venography(DPV) and computed tomography angiography(CTA) to reveal the manifestations of the portal venous system. The vessels measured included the left portal vein(LPV), right portal vein(RPV), main portal vein(MPV) and the portal vein bifurcation(PVB). Results: Nine males and 5 females, with a median age of 40.5 years, were included in the study. No significant difference was found in the diameters of the LPV or RPV measured by DPV and CTA. The visualization in terms of LPV, RPV and PVB measured by DPV was higher than that by CTA. There was a significant association between LPV/RPV and PVB/MPV in term of visibility revealed with DPV( P = 0.01), while this association was not observed with CTA. According to the imaging features of the portal vein measured by DPV, CTPV was classified into three categories to facilitate the diagnosis and treatment. Conclusions: DPV was more accurate than CTA for revealing the course of the intrahepatic portal vein in patients with CTPV. The classification of CTPV, that originated from the imaging features of the portal vein revealed by DPV, may provide a new perspective for the diagnosis and treatment of CTPV.

关键词： Cavernous transformation of the portal vein Classification Direct portal venography Intrahepatic portal venous system

Molecular crowding electrolytes for stabilizing Zn metal anode in rechargeable aqueous batteries

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Chinese Chemical Letters 2024年第7期35卷 445-451页

作者： Li lin Song-lin Tian Zhen-Yu Hu Yu Zhang Li-min Chang Jia-Jun Wang Wan-Qiang Liu Qing-Shuang Wang Fang Wang School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China School of Life Science and Technology Changchun University of Science and TechnologyChangchun 130022China Key Laboratory of Preparation and Applications of Environmental Friendly Materials of the ministry of Education Jilin Normal UniversityChangchun 130103China Zhongshan Institute of Changchun University of Science and Technology Zhongshan 528437China

A solid electrolyte interphase(SEI)with a robust mechanical property and a high ionic conductivity is imperative for high-performance zinc metal ***,it is difficult to form such a SEI directly from an *** this work,a molecular crowding effect is based on the introduction of Zn(OTF)_(2)and Zn(ClO_(4))_(2)to 2 mol/L ZnSO_(4)*** and experiments indicate that the Zn(OTF)_(2)and Zn(ClO_(4))_(2)not only create a molecularly crowded electrolyte environment to promote the interaction of Zn^(2+)and OTF^(-),but also participate in the reduction to construct a robust and high ionic-conductive SEI,thus promoting metal zinc deposition to the(002)crystal *** this molecular crowding electrolyte,a high current density of 1 mA/cm^(2)can be obtained by assembling symmetric batteries with Zn as the anode for over 1000 *** in a temperature environment of-10℃,a current density of 1 mA/cm^(2)can be obtained by assembling symmetric batteries with Zn for over 200 ***//Bi_(2)S_(3)/VS4@C cells achieve a CE rate of up to 99.81%over 1000 ***,the utilization of a molecular crowding electrolyte is deemed a highly effective approach to fabricating a sophisticated SEI for a zinc anode.

关键词： Zinc ion batteries Anode Electrolyte Solid electrolyte interphase Molecular crowding effect

A General Electrochemical Synthesis of Sulfonimidoyl Fluorides,Azides,and Acetates

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CCS Chemistry 2024年第8期6卷 2021-2030页

作者： Yi-min Jiang Yong-Ying lin lingyun Zhu Yi Yu Yuanming Li Yuqi lin Ke-Yin Ye Key Laboratory of Molecule Synthesis and Function Discovery(Fujian Province University) College of ChemistryFuzhou UniversityFuzhou 350108

Sulfonimidoyl fluorides,the aza-bioisostere of sulfonyl fluorides,are emerging as a promising linkage agent in the sulfur(VI)fluoride exchange reaction(SuFEx).However,conventional synthetic approaches typically require the use of either unstable sulfonimidoyl chlorides,toxic and corrosive sulfur fluorides,or expensive electrophilic fluorinating ***,we report an electrochemistry-enabled oxidative nucleophilic fluorination of readily available and bench-stable sulfinamides using a commercially available and easy-to-handle triethylamine *** other nucleophilic agents,this electrochemical approach also serves as a general approach to diverse sulfonimidoyl derivatives,including sulfonimidoyl azides and acetates.

关键词： electrochemistry click chemistry sulfur(VI)fluoride exchange reaction sulfonimidoyl fluoride sulfinamide