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The atomic interface effect of single atom catalysts for electrochemical hydrogen peroxide production

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Nano Research 2023年第8期16卷 10724-10741页

作者： kaiyuan Liu Pengwan Chen Zhiyi sun Wenxing Chen Qiang Zhou Xin Gao State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Advanced Technology Research Institute Beijing Institute of TechnologyJinan 250307China Energy&Catalysis Center School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China China Academy of Ordnance Science Beijing 100089China

Producing hydrogen peroxide(H_(2)O_(2))through an electrochemical oxygen reduction reaction(ORR)is a safe,green strategy and a promising alternative to traditional energy-intensive anthraquinone processes.Air and renewable power could be utilized for onsite and decentralized H_(2)O_(2)production,demonstrating significant application potential.Currently,single atom catalysts(SACs)have demonstrated significant advantages in the catalytic production of H_(2)O_(2)in 2e−ORR.However,the selectivity of SACs in ORR once puzzled researchers.This article reviews the research on the development and achievements of H_(2)O_(2)production by SACs catalysis in recent years.Especially,the structure-performance relationship is a guide to designing new SACs.Combining advanced characterization techniques and theoretical calculation methods,researchers have a clearer and more thorough understanding of the impact of the atomic interface of SACs on ORR catalytic performance.The coordination moiety formed between the active metal center atom and the support seriously determines the selectivity of SACs,mainly manifested in the adsorption of*OOH intermediates.Particularly,the atomic interface of metal atoms together with O/N co-coordination exhibit high selectivity and mass activity,and heteroatoms or functional groups on carbon supports present synergistic effects to promote the production of H_(2)O_(2)in 2e−ORR.Fine and accurate regulation of the atomic interface of SACs directly affects the 2e−ORR performance of the catalysts.Therefore,it is important to deeply understand the atomic interface of SACs and contribute to the development of novel catalysts.

关键词： single atom catalysts(SACs) atomic interface effect hydrogen peroxide(H_(2)O_(2))production electrochemical catalysis

Recovering the electrochemical window by forming a localized solvation nanostructure in ionic liquids with trace water

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Science China Chemistry 2022年第1期65卷 96-105页

作者： Jianing Meng Meng Ye Yue Wang Yinglun sun Xu Zhang kaiyuan Shi Xingbin Yan School of Materials Science and Engineering Sun Yat-Sen UniversityGuangzhou 510275China Laboratory of Clean Energy Chemistry and Materials Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China School of Petrochemical Engineering Lanzhou University of TechnologyLanzhou 730050China School of Physical Science and Technology Lanzhou UniversityLanzhou 730000China

Motivated by the fascinating merits of wide electrochemical stability window(ESW)and nonflammability,ionic liquids(ILs)have been utilized as advanced electrolytes in various emerging electrochemical energy storage technologies.However,ILs are hygroscopic to the water in the air and the presence of trace water will narrow the ESW of ILs.In this article,we report that a localized solvation nanostructure(LSNS)is formed in ILs,which plays an important role in fully recovering the originally decreased ESW of[EMIM][TFSI]IL owing to the trace water.Such LSNS is consisted of Li^(+)ions with water molecules as the center,TFSI-anions as the secondary periphery and EMIM^(+)cations as the outermost layer after adding the proper amount of LiTFSI.This nanostructure can restrain the possibility of trace water to approach the electrode/electrolyte interfaces and adverse redox reactions,thereby recovering the ESW.Moreover,the effectiveness of this strategy in different kinds of ILs to fully recover ESW decreasing is verified.This article comes up with a feasible method to eliminate the trace water caused ESW drop for ILbased electrolytes and provides a new insight for understanding the molecular-level interaction between different ions in ILs with water molecules.

关键词： supercapacitor ionic liquid electrochemical window lithium salt trace water

Transmission Dynamics and Epidemiological Characteristics of the SARS-CoV-2 Delta Variant ― Hunan Province, China, 2021

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China CDC weekly 2023年第3期5卷 56-62,I0006-I0009页

作者： Kaiwei Luo Yanpeng Wu Yan Wang Ziyan Liu Lan Yi Shanlu Zhao Xuemei Yan Hao Yang Kaiyuan Sun Marco Ajelli Shixiong Hu Hongjie Yu Hunan Provincial Center for Disease Control and Prevention Workstation for Emerging Infectious Disease Control and PreventionChinese Academy of Medical SciencesChangsha CityHunan ProvinceChina Shanghai Institute of Infectious Disease and Biosecurity Fudan UniversityShanghai MunicipalityChina School of Public Health Fudan UniversityKey Laboratory of Public Health SafetyMinistry of EducationShanghai MunicipalityChina Division of International Epidemiology and Population Studies Fogarty International CenterNational Institutes of HealthBethesdaMDUSA Laboratory of Computational Epidemiology and Public Health Department of Epidemiology and BiostatisticsIndiana University School of Public HealthBloomingtonINUSA

Monitoring changes in the epidemiologic features between different severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)variants is key to understanding the evolution of viral fitness in the host population.Here,we analyzed a successfully contained local outbreak of the Delta variant that took place in Hunan,China,in July–August,2021.Detailed data on SARS-CoV-2 infections and their contacts were collected during the outbreak.By leveraging these data,we estimated key epidemiological parameters,including the incubation period,serial interval,and generation time.We constructed a generalized linear mixed-effects model(GLMM)to quantify risk factors for Delta infection and transmission.Between July 28 and August 15,2021,a total of 129 infections and their 2,118 close contacts were identified during the outbreak in Hunan Province.

关键词： Hunan population Province

Optimal Auxiliary Frequency Control of Wind Turbine Generators and Coordination with Synchronous Generators

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CSEE Journal of Power and Energy Systems 2021年第1期7卷 78-85页

作者： Ming sun Yong Min Lei Chen kaiyuan Hou Deming Xia Hangyin Mao State Key Laboratory of Control and Simulation of Power System and Generation Equipment Department of Electrical EngineeringTsinghua UniversityBeijing 100084China with Northeast Branch of State Grid Corporation of China Shenyang 110180Liaoning ProvinceChina with State Grid Zhejiang Electric Power Co.LTD. Hangzhou 310007Zhejiang ProvinceChina

Auxiliary frequency control of a wind turbine generator(WTG) has been widely used to enhance the frequencysecurity of power systems with high penetration of renewableenergy. Previous studies recommend two types of control schemes,including frequency droop control and emulated inertia control,which simulate the response characteristics of the synchronousgenerator (SG). This paper plans to further explore the optimalauxiliary frequency control of the wind turbine based on previousresearch. First, it is determined that the virtual inertia control haslittle effect on the maximum rate of change of frequency (MaxROCOF)if the time delay of the control link of WTG is taken intoconsideration. Secondly, if a WTG operates in maximum powerpoint tracking (MPPT) mode and uses the rotor deceleration forfrequency modulation, its optimal auxiliary frequency control willcontain only droop control. Furthermore, if the droop control isproperly delayed, better system frequency response (SFR) willbe obtained. The reason is that coordination between the WTGand SG is important for SFR when the frequency modulationcapability of the WTG is limited. The frequency modulationcapability of the WTG is required to be released more properly.Therefore, when designing optimal auxiliary frequency controlfor the WTG, a better control scheme is worth further study.

关键词： Frequency droop control power system frequency security rate of change of frequency(ROCOF) virtual inertia control wind turbine generator auxiliary frequency control

Physical model test and numerical simulation on the failure mechanism of the roadway in layered soft rocks

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International Journal of Mining Science and Technology 2021年第2期31卷 291-302页

作者： Xiaoming sun Chengwei Zhao Yong Zhang Feng Chen Shangkun Zhang kaiyuan Zhang State Key Laboratory for GeoMechanics and Deep Underground Engineering China University of Mining and Technology-BeijingBeijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology-BeijingBeijing 100083China School of Civil Engineering Nanyang Institute of TechnologyNanyang 473004China

To explore the failure mechanism of roadway in layered soft rocks,a physical model with the physically finite elemental slab assemblage(PFESA)method was established.Infrared thermography and a video camera were employed to capture thermal responses and deformation.The model results showed that layered soft roadway suffered from large deformation.A three-dimensional distinct element code(3 DEC)model with tetrahedral blocks was built to capture the characteristics of roadway deformation,stress,and cracks.The results showed two failure patterns,layer bending fracture and layer slipping after excavation.The layer bending fracture occurred at positions where the normal direction of layers pointed to the inside of the roadway and the layer slipping occurred in the ribs.Six schemes were proposed to investigate the effects of layered soft rocks.The results showed that the deformation of ribs was obviously larger than that of the roof and floor when the roadway passed through three types of strata.When the roadway was completely in a coal seam,the change of deformation in ribs was not obvious,while the deformation in the roof and floor increased obviously.These results can provide guidance for excavation and support design of roadways in layered soft rocks.

关键词： Failure mechanism Physical model test 3DEC Layered soft rocks Large deformation

Associations of cholecystectomy with the risk of colorectal cancer: a Mendelian randomization study

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Chinese Medical Journal 2023年第7期136卷 840-847页

作者： Lanlan Chen Zhongqi Fan Xiaodong sun Wei Qiu Wentao Mu kaiyuan Chai Yannan Cao Guangyi Wang Guoyue Lv Department of Hepatobiliary and Pancreatic Surgery General Surgery CenterFirst Hospital of Jilin UniversityChangchunJilin 130021China

Background:Cholecystectomy is a standard surgery for patients suffering from gallbladder diseases,while the causal effects of cholecystectomy on colorectal cancer(CRC)and other complications are still unknown.Methods:We obtained genetic variants associated with cholecystectomy at a genome-wide significant level(P value<5×10^(-8))as instrumental variables(IVs)and performed Mendelian randomization(MR)to identify the complications of cholecystectomy.Furthermore,the cholelithiasis was also treated as the exposure to compare its causal effects to those of cholecystectomy,and multivariable MR analysis was carried out to judge whether the effect of cholecystectomy was independent of cholelithiasis.The study was reported based on Strengthening the Reporting of Observational Studies in Epidemiology Using Mendelian Randomization guidelines.Results:The selected IVs explained 1.76%variance of cholecystectomy.Our MR analysis suggested that cholecystectomy cannot elevate the risk of CRC(odds ratio[OR]=1.543,95%confidence interval[CI]:0.607–3.924).Also,it was not significant in either colon or rectum cancer.Intriguingly,cholecystectomy might decrease the risk of Crohn’s disease(OR=0.078,95%CI:0.016-0.368)and coronary heart disease(OR=0.352,95%CI:0.164–0.756).However,it might increase the risk of irritable bowel syndrome(IBS)(OR=7.573,95%CI:1.096–52.318).Cholelithiasis could increase the risk of CRC in the largest population(OR=1.041,95%CI:1.010–1.073).The multivariable MR analysis suggested that genetic liability to cholelithiasis could increase the risk of CRC in the largest population(OR=1.061,95%CI:1.002–1.125)after adjustment of cholecystectomy.Conclusions:The study indicated that cholecystectomy might not increase the risk of CRC,but such a conclusion needs further proving by clinical equivalence.Additionally,it might increase the risk of IBS,which should be paid attention to in clinical practice.

关键词： Cholelithiasis Irritable bowel syndrome Inflammatory bowel disease Causal inference Colorectal cancer Cholecystectomy Mendelian randomization

The risk of mpox importation and subsequent outbreak potential in Chinese mainland: a retrospective statistical modelling study

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贫困所致传染病(英文) 2024年第1期13卷 63-73页

作者： Deng Xiaowei Tian Yuyang Zou Junyi Yang Juan sun kaiyuan Yu Hongjie School of Public Health Key Laboratory of Public Health Safety 3. Ministry of Education 4. Fudan University 5. Shanghai 200032 6. China 7. Division of International Epidemiology and Population Studies 8. Fogarty International Center 9. National Institutes of Health 10. Bethesda 11. MD 12. USA

Background The 2022-2023 mpox (monkeypox) outbreak has spread rapidly across multiple countries in the non-endemic region, mainly among men who have sex with men (MSM). In this study, we aimed to evaluate mpox’s importation risk, border screening effectiveness and the risk of local outbreak in Chinese mainland.Methods We estimated the risk of mpox importation in Chinese mainland from April 14 to September 11, 2022 using the number of reported mpox cases during this multi-country outbreak from Global.health and the international air-travel data from Official Aviation Guide. We constructed a probabilistic model to simulate the effectiveness of a border screening scenario during the mpox outbreak and a hypothetical scenario with less stringent quarantine requirement. And we further evaluated the mpox outbreak potential given that undetected mpox infections were introduced into men who have sex with men, considering different transmissibility, population immunity and population activity.Results We found that the reduced international air-travel volume and stringent border entry policy decreased about 94% and 69% mpox importations respectively. Under the quarantine policy, 15-19% of imported infections would remain undetected. Once a case of mpox is introduced into active MSM population with almost no population immunity, the risk of triggering local transmission is estimated at 42%, and would rise to > 95% with over six cases.Conclusions Our study demonstrates that the reduced international air-travel volume and stringent border entry policy during the COVID-19 pandemic reduced mpox importations prominently. However, the risk could be substantially higher with the recovery of air-travel volume to pre-pandemic level. Mpox could emerge as a public health threat for Chinese mainland given its large MSM community.

关键词： Mpox (Monkeypox) Importation risk International air travel Statistical modelling Men who have sex with men

A Retrospective Modeling Study of the Targeted Non-Pharmaceutical Interventions During the Xinfadi Outbreak in the Early Stage of the COVID-19 Pandemic — Beijing, China, 2020

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China CDC weekly 2023年第5期5卷 108-112,I0007-I0011页

作者： Yan Wang Kaiyuan Sun Yang Pan Lan Yi Da Huo Yanpeng Wu Shuaibing Dong Jinxin Guo Xiangfeng Dou Wei Wang Shuangsheng Wu Xufang Bai Hongjie Yu Quanyi Wang School of Public Health Fudan UniversityKey Laboratory of Public Health SafetyMinistry of EducationShanghai MunicipalityChina Division of International Epidemiology and Population Studies Fogarty International CenterNational Institutes of HealthBethesdaMDUSA Beijing Center for Disease Prevention and Control Beijing MunicipalityChina Shanghai Institute of Infectious Disease and Biosecurity Fudan UniversityShanghai MunicipalityChina

Summary What is already known about this topic?China has repeatedly contained multiple severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)outbreaks through a comprehensive set of targeted nonpharmaceutical int... 详细信息

关键词： acute respiratory assessed

WELL-FORGED "WALKING GOLD"——THE SHEEP BREEDING INDUSTRY IN THE GAMPA COUNTY

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China's Tibet 2018年第1期29卷 16-19页

作者： sun kaiyuan Zhang Xiaoming Wang Jie

It is just the dawn,but the sheepfolds have already begun to move restlessly.sunlight makes its way in.Tashi Tsedan and Redan open the sheepfolds one after another.Flocks of sheep suddenly gush out like an influx of water from an opened gate.These two herdsmen from Jirong Village in Drik Town of Gampa County are fulfilling their duty grazing these flocks of Gampa sheep,a well-known breed of Tibetan sheep.

关键词： THE SHEEP BREEDING INDUSTRY IN THE GAMPA COUNTY WALKING GOLD WELL-FORGED