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Combination of a reaction cell and an ultra-high vacuum system for the in situ preparation and characterization of a model catalyst

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Nuclear Science and Techniques 2023年第5期34卷 13-21页

作者： Yi-jing Zang Shu-Cheng shi yong Han Hui Zhang wei-Jia wang peng Liu Mao Ye zhi Liu State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Center for Transformative Science ShanghaiTech UniversityShanghai 201210China University of Chinese Academy of Sciences Beijing 100049China

An in-depth understanding of the structure-activity relationship between the surface structure,chemical composition,adsorption and desorption of molecules,and their reaction activity and selectivity is necessary for the rational design of high-performance ***,we present a method for studying catalytic mechanisms using a combination of in situ reaction cells and surface science *** proposed system consists of four parts:preparation chamber,temperatureprogrammed desorption(TPD)chamber,quick load-lock chamber,and in situ reaction *** preparation chamber was equipped with setups based on the surface science techniques used for standard sample preparation and characterization,including an Ar+sputter gun,Auger electron spectrometer,and a low-energy electron *** a well-defined model catalyst was prepared,the sample was transferred to a TPD chamber to investigate the adsorption and desorption of the probe molecule,or to the reaction cell,to measure the catalytic activity.A thermal desorption experiment for methanol on a clean Cu(111)surface was conducted to demonstrate the functionality of the preparation and TPD ***,the repeatability of the in situ reaction cell experiment was verified by CO_(2) hydrogenation on the Ni(110)*** a reaction pressure of 800 Torr at 673 K,turnover frequencies for the methanation reaction and reverse water-gas shift reaction were 0.15 and 7.55 Ni atom^(-1) s^(-1),respectively.

关键词： Surface science Model catalysts Ultra-high vacuum Temperature-programmed desorption In situ reaction cell

Terahertz superconducting kinetic inductance detectors demonstrating photon-noise-limited performance and intrinsic generation-recombination noise

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Science China(Physics,Mechanics & Astronomy) 2022年第3期65卷 106-113页

作者： Qing shi jing Li Qiang zhi Zheng wang wei Miao Sheng-Cai shi Purple Mountain Observatory Chinese Academy of SciencesNanjing 210034China School of Astronomy&Space Science University of Science and Technology of ChinaHefei 230026China

The development of large-format detector arrays with background-limited performance is of particular interest at the terahertz(THz) band, which is a unique band in search of our cosmic origins. With high sensitivity and being more promising in the pixel number and multiplexing technology, superconducting kinetic inductance detectors(KID) are emerging as a major choice of detectors of this type. Here we fabricate three-THz-band(0.35/0.85/1.4 THz) KIDs on a single chip from a 120-nm-thick aluminum(Al) superconducting film and measure photon-noise-limited performance and intrinsic generation-recombination noise at high(>1 p W) and low(<1 f W) optical radiation power, respectively. Their responses to blackbody(optical) radiation are proven to be purely from photons compared with the responses of two dark KIDs intentionally arranged on the same detector chip. The lowest optical noise equivalent power(NEP) reaches 6×10^(-18)W/Hz^(0.5)and the optical coupling efficiency is in the range of 49%-56% for the three KIDs, which are in good agreement with the simulation results.

关键词： terahertz kinetic inductance detectors(KID) photon-noise generation-recombination noise

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Identifying potential flavonoid biosynthesis regulator in Zanthoxylum bungeanum Maxim. by genome-wide characterization of the MYB transcription factor gene family

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Journal of Integrative Agriculture 2022年第7期21卷 1997-2018页

作者： wang Xiang-yuan TIAN Lu FENG shi-jing wei An-zhi College of Forestry Northwest A&F UniversityYangling 712100P.R.China Research Centre for Engineering and Technology of Zanthoxylum State Forestry Administration Yang ling 712100P.R.China College of Forestry Guizhou UniversityGuiyang 550025P.R.China

Plant MYB transcription factors(TFs) play crucial roles in regulating the biosynthesis of flavonoids but current analysis on their role in Zanthoxylum bungeanum Maxim.(ZBM) is far from comprehensive. In this study, we identified 270 MYB genes in ZBM and divided them into four subfamilies. The R2 R3-MYB(ZbMYB) category contained 251 genes and was classified into 33 subfamilies according to their phylogenetic results and sequence similarity. These subfamilies included 24 subgroups containing both MYBs of ZBM plants and AtMYBs, and nine subgroups containing only ZBM MYBs or AtMYBs. ZbMYBs with similar functions clustered into the same subgroup, indicating functional conservation. The subcellular localization analysis predicted that most ZbMYB genes were found in the nucleus. The transposed duplications appeared to play a major role in the expansion of the MYB gene family in ZBM. Through phylogenetic analysis and transcriptome profiling, it was found that 28 ZbMYB genes may regulate the biosynthesis of flavonoids in ZBM, and these genes expression presented distinct temporal and spatial expression patterns. In different fruit development stages of ZBM, the expression patterns of EVM0042160 and EVM0033809 genes obtained by qRT-PCR analysis are very similar to the flavonoid and anthocyanin content curves in ZBM. Further correlation analysis showed that the content of flavonoids in different fruit development stages and the transcript abundance levels of 28 ZbMYB genes have different degrees of correlation relationship. These results indicated that the ZbMYB genes might be involved in the flavonoid metabolic pathway. This comprehensive and systematic analysis of MYB family genes provided a solid foundation for further functional analysis of MYB TFs in ZBM.

关键词： Zanthoxylum bungeanum Maxim. MYB transcription factor expression pattern regulation of flavonoid biosynthesis

Impacts of the COVID-19 pandemic on rural poverty and policy responses in China

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Journal of Integrative Agriculture 2020年第12期19卷 2946-2964页

作者： LUO Ren-fu LIU Cheng-fang GAO jing-jing wang Tian-yi zhi Hua-yong shi peng-fei HUANG Ji-kun China Center for Agricultural Policy School of Advanced Agriculture SciencesPeking UniversityBeijing 100871P.R.China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

Given the sudden outbreak of the COVID-19 pandemic,a timely study on the impacts of and policy response to the pandemic on rural poverty in China is critically important because China has aimed to completely eradicate extreme poverty by the end of *** paper uses data from the latest round of a nationally representative household panel survey to examine the impacts of the pandemic on rural poverty in *** data show that 11.9%of sample households were ever officially registered as poor households between 2013 and 2019,and this poverty incidence fell to 2.7%by the end of *** the middle February of 2020,23%of the households who have graduated from poverty since 2013 perceived that they would fall back into poverty due to the *** those never poor households,7.1%perceived that they would possibly fall into poverty due to the *** from both descriptive and multivariate analyses consistently show the interruptions that the pandemic caused in off-farm employment is an important channel that led households to perceive of falling back into or falling into *** also find households in the bottom four quintiles when ranked in terms of household income per capita are much more likely to perceive themselves of falling back into or falling into poverty during this pandemic than those in the richest ***,our results show that the education and age of household heads,as well as being from Hubei Province matter in explaining household perception about falling back into or falling into poverty in some cases but not *** paper concludes with a set of policy responses that China has taken to mitigate the impact of COVID-19 pandemic on poverty alleviation.

关键词： COVID-19 pandemic perception poverty rural households China

Condition dependence of Zr electrochemical reactions and morphological evolution of Zr deposits in molten salt

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Science China Chemistry 2017年第2期60卷 264-274页

作者： Kui Liu Ya-Lan Liu jing-Wen Pang Li-yong Yuan Lin wang zhi-Fang Chai wei-Qun shi Laboratory of Nuclear Energy Chemistry Institute of High Energy PhysicsChinese Academy of Sciences School of Radiological & Interdisciplinary Sciences Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education InstitutionsSoochow University

This work presents a comprehensive study for the electrochemical behaviors of zirconium in LiCl-KCl *** effects of stirring,temperature and Zr concentration on the electrode reactions,the ZrCl_4 sublimation from the melt,microcosmic morphologies of Zr deposits(ZrCl and Zr)obtained at different potential and temperature have been *** behaviors of Zr(Ⅳ),on a large concentration range from 0.13%to 2.28%in melt,show a multiple-step reaction involving Zr(Ⅳ),Zr(Ⅱ),ZrCl and Zr *** plays a crucial role on the changes of Zr(IV)reduction behavior on the solid *** Zr(Ⅳ)/ZrCl couple is more easily observed at lower temperature and gradually diminishes with the increase of *** Zr(Ⅳ)/Zr(Ⅱ)and Zr(Ⅱ)/Zr reactions are predominant on the W electrode at higher *** 673 K,a layered structure of insoluble ZrCl formed by potentiostatic electrolyses at 1.1 V was visualized by scanning electron microscopy-energy dispersive X-ray(SEM-EDS),while only Zr metal particles was observed at higher temperature than 773 *** evolution of the Zr-based structure and size corresponding to the ZrCl and Zr metal based on different potentiostatic electrolysis was *** average particle size of the Zr metalparticles increases with the increase of temperature.

关键词： zirconium electrochemistry influence factor LiCl-KCl pyroprocessing

Photocatalytic nonoxidative coupling of methane to ethylene over carbon-doped ZnO/Au catalysts

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Science China Chemistry 2023年第11期66卷 3252-3261页

作者： jing wang Yuhao peng wei Xiao College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power SourcesWuhan UniversityWuhan 430072China

A photocatalytic nonoxidative coupling of methane to multi-carbon compounds remains a huge challenge due to its high dissociation energy of C–H bonds and sluggish charge carrier ***-modified carbon-doped ZnO(C-ZnO/Au)photocatalyst is constructed by an interfacial modification-assisted self-assembly approach for efficient photocatalytic nonoxidative coupling of methane to ethylene and hydrogen(2CH_4=C_2H_4+2H_2).Benefitting from the presence of C-ZnO/Au interfaces,the catalyst not only weakens the excitonic confinement to improve the photogenerated charge carrier separation,but also enhances the stability of lattice oxygen to suppress C_2H_4 ***,this hybrid catalyst also accelerates the generation of Zn~+–O~–pairs to activate C–H bonds,stabilizes the important reaction intermediate(*OCH_3)to achieve the C–C coupling,and promotes the generation of low-valence Zn to accelerate the dehydrogenation of the*OC_2H_5 into C_2H_***,a stable photocatalytic methane conversion performance can be achieved over C-ZnO/Au heterojunctions with a stoichiometric generation of the oxidation product(C_2H_4,45.85μmol g~(-1)h~(-1))and reduction product(H_2,88.07μmol g~(-1)h~(-1)).This work provides deep insights into the elemental doping and oxide/Au interfaces for the enhanced photocatalytic activity and product selectivity under mild conditions in the absence of extra oxidants.

关键词： carbon-doped ZnO charge separation C–H bond activation photocatalytic nonoxidative coupling of methane

Development of a recombinant pB602L-based indirect ELISA assay for detecting antibodies against African swine fever virus in pigs

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Journal of Integrative Agriculture 2022年第3期21卷 819-825页

作者： wang peng-fei wang Ming shi zhi-bin SUN Zhen-zhao wei Li-li LIU Zai-si wang shi-da HE Xi-jun wang jing-fei State Key Laboratory of Veterinary Biotechnology Harbin Veterinary Research InstituteChinese Academy of Agricultural SciencesHarbin 150069P.R.China

African swine fever(ASF),caused by the African swine fever virus(ASFV),is a devastating disease of domestic and wild *** is no effective vaccine,and the control of the disease relies mainly on surveillance and early detection of infected ***,serological assays,such as ELISA,have been developed mainly based on recombinant structural viral proteins of ASFV,including p72,p54,and ***,the antibodies against these proteins do not provide efficient protection against ASFV infection in ***,new serological assays that can be applied for clinical diagnosis and evaluating serological immune response in vaccinated pigs are still *** this study,we expressed and purified a recombinant p B602 L *** purified p B602 L protein was then used as an antigen to develop an indirect ELISA *** assay has no cross-reaction with the anti-sera against the 15 most common pig pathogens in China,such as classical swine fever virus,pseudorabies virus,and porcine *** assay and a commercial ELISA kit were then used to detect 60 field pig serum samples,including an unknown number of antiASFV *** coincidence of the two assays was 95%.Furthermore,the p B602 L-based ELISA was employed to test the antibody responses to the seven-gene-deleted ASFV strain HLJ/18-7 GD in *** results showed that the antibody levels in all vaccinated pigs,starting from the 10 th day post-inoculation,have increased continuously during the observation period of 45 *** results indicate that this p B602 L-based indirect ELISA assay can be employed potentially in the field of ASFV diagnosis.

关键词： African swine fever virus pB602L recombinant protein indirect ELISA assay pig

Viral-mediated gene therapy in pediatric neurological disorders

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World Journal of Pediatrics 2024年第6期20卷 533-555页

作者： jing peng wei-wei Zou Xiao-Lei wang zhi-Guo Zhang Ran Huo Li Yang Department of Pediatrics Clinical Research Center for Chidren Neurodevelopmental disablities of Hunan ProvinceXiangya HospitalCentral South UniversityChangsha 410008China Reproductive Medicine Center Department of Obstetrics and Gynecologythe First Affiliated Hospital of Anhui Medical UniversityHefeiChina State Key Laboratory of Reproductive Medicine Nanjing Medical UniversityNanjingChina

Background Due to the broad application of next-generation sequencing,the molecular diagnosis of genetic disorders in pediatric neurology is no longer an unachievable ***,treatments for neurological genetic disorders in children remain primarily *** the other hand,with the continuous evolution of therapeutic viral vectors,gene therapy is becoming a clinical *** this perspective,we wrote this review to illustrate the current state regarding viral-mediated gene therapy in childhood neurological *** sources We searched databases,including PubMed and Google Scholar,using the keywords"adenovirus vector,""lentivirus vector,"and"AAv"for gene therapy,and"immunoreaction induced by gene therapy vectors,""administration routes of gene therapy vectors,"and"gene therapy"with"NCL,""SMA,""DMD,""congenital myopathy,""MPS""leukodystrophy,"or"pediatric metabolic disorders".We also screened the database of *** using the keywords"gene therapy for children"and then filtered the results with the ones aimed at neurological *** time range of the search procedure was from the inception of the databases to the *** We presented the characteristics of commonly used viral vectors for gene therapy for pediatric neurological disorders and summarized their merits and drawbacks,the administration routes of each vector,the research progress,and the clinical application status of viral-mediated gene therapy on pediatric neurological *** Viral-mediated gene therapy is on the brink of broad clinical ***-mediated gene therapy will dramatically change the treatment pattern of childhood neurological disorders,and many children with incurable diseases will meet the dawn of a ***,the vectors must be optimized for better safety and efficacy.

关键词： Gene therapy Neurological disorders Pediatrics Viral vectors

Stabilization of nanoscale zero-valent iron in water with mesoporous carbon(n ZVI@MC)

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Journal of Environmental Sciences 2019年第7期31卷 28-33页

作者： Junming shi jing wang wei wang wei Teng wei-xian Zhang State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and Engineering Tongji University School of Chemical Science and Engineering Tongji University

Two challenges persist in the applications of nanoscale zero-valent iron(nZVI) for environmental remediation and waste treatment: limited mobility due to rapid aggregation and short lifespan in water due to quick oxidation. Herein, we report the nZVI incorporated into mesoporous carbon(MC) to enhance stability in aqueous solution and mobility in porous media. Meanwhile, the reactivity of nZVI is preserved thanks to high temperature treatment and confinement of carbon framework. Small-sized(～16 nm) nZVI nanoparticles are uniformly dispersed in the whole carbon frameworks. Importantly, the nanoparticles are partially trapped across the carbon walls with a portion exposed to the mesopore channels. This unique structure not only is conductive to hold the nZVI tightly to avoid aggregation during mobility but also provides accessible active sites for reactivity. This new type of nanomaterial contains ～10 wt% of iron. The nZVI@MC possesses a high surface area(～ 500 m^2/g) and uniform mesopores(～ 4.2 nm) for efficient pollutant diffusion and reactions. Also, high porosity of nZVI@MC contributes to the stability and mobility of nZVI. Laboratory column experiments further demonstrate that nZVI@MC suspension(～4 g Fe/L) can pass through sand columns much more efficiently than bare nZVI while the high reactivity of nZVI@MC is confirmed from reactions with Ni(II). It exhibits remarkably better performance in nickel(20 mg/L) extraction than mesoporous carbon, with 88.0% and 33.0%uptake in 5 min, respectively.

关键词： Mesoporous carbon Nanoscale zero-valent iron Mobility Porous media Heavy metal removal