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Electrochemical Study on Hydrogen Evolution and CO2 Reduction on Pt Electrode in Acid Solutions with Different pH

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Chinese Journal of Chemical Physics 2018年第5期31卷 626-634,735页

作者： jing yang Jie wei wei Chen yan-xia Chen Hefei National Laboratory for Physical Science at the Microscale and Department of Chemical Physics University of Science and Technology of ChinaHefei 230026China

Hydrogen evolution reaction(HER)is the major cathodic reaction which competes CO2 reduction reaction(CO2 RR)on Pt *** level understanding on how these two reactions interact with each other and what the key factors are of CO2 RR kinetics and selectivity will be of great help in optimizing electrolysers for CO2 *** this work,we report our results of hydrogen evolution and CO2 reduction on Pt(111)and Pt film electrodes in CO2 saturated acid solution by cyclic voltammetry and infrared *** solution with pH>2,the major process is HER and the interfacial pH increases abruptly during HER;COad is the only adsorbed intermediate detected in CO2 reduction by infrared spectroscopy;the rate for COad formation increases with the coverage of UPD-H and reaches maximum at the onset potential for HER;the decrease of COad formation under HER is attributed to the available limited sites and the limited residence time for the reduction intermediate(Had),which is necessary for CO2 adsorption and reduction.

关键词： Hydrogen evolution reaction CO2 Reduction Pt(111) Acidic solution pH effect Infrared spectroscopy

Evolution of plasticized MnO–Al2O3–SiO2-based nonmetallic inclusion in 18wt%Cr-8wt% Ni stainless steel and its properties during soaking process

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International Journal of Minerals,Metallurgy and Materials 2020年第3期27卷 328-339页

作者： jing Guo Xing-run Chen Shao-wei Han yan yan Han-jie Guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Jiuquan Iron and Steel Group Corporation Jiayuguan 735100China Beijing Shougang Co.Ltd. Qian'an 064400China

The properties of MnO–Al2O3–SiO2-based plasticized inclusion are likely to change during soaking process due to its low melting point. In this study, the evolution of the MnO–Al2O3–SiO2-based inclusion of 18 wt%Cr-8 wt%Ni stainless steel under isothermal soaking process at 1250°C for different times was investigated by laboratory-scale experiments and thermodynamic analysis. The results showed that the inclusion population density increased at the first stage and then decreased while their average size first decreased and then increased. In addition, almost no Cr2O3-concentrated regions existed within the inclusion before soaking, but more and more Cr2O3 precipitates were formed during soaking. Furthermore, the plasticity of the inclusion deteriorated due to a decrease in the amount of liquid phase and an increase in the high-melting-pointphase MnO–Cr2O3 spinel after the soaking process. In-situ observations by high-temperature confocal laser scanning microscopy(CLSM) confirmed that liquid phases were produced in the inclusions and the inclusions grew rather quickly during the soaking process. Both the experimental results and thermodynamic analysis conclude that there are three routes for inclusion evolution during the soaking process. In particular, Ostwald ripening plays an important role in the inclusion evolution, i.e., MnO–Al2O3–SiO2-based inclusions grow by absorbing the newly precipitated smaller-size MnO–Cr2O3 inclusions.

关键词： nonmetallic inclusion soaking process Ostwald ripening stainless steel

A Blockchain Based Mobile Crowdsensing Market

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China Communications 2019年第6期16卷 31-41页

作者： Xin wei Yong yan wei Jiang jing Shen Xuesong Qiu State Key Laboratory of Networking and Switching Technology of Beijing University of Posts and Telecommunications Beijing 100876China State Grid Zhejiang Electric Power Research Institute Hangzhou 310014China Internet department of State Grid Corporation of China Beijing 100031China State Grid Henan Electric Power Company Information&Telecommunication Company Zhengzhou 450000China

Mobile crowdsensing(MCS)is an emerging pattern which means task initiators attract mobile users sensing with their own devices by some *** could exploit idle resources in low cost,while it has lots of flaws,which impede its ***,isolations between different MCS systems leads to wastage of social ***’s more,current MCS always operate in a centralized way,which causes it vulnerable and *** is a promising technology which could supply a credible and transparent *** paper construct a blockchain based MCS market and design smart contract for its *** our design,platform breaks isolation by blockchain,task initiators and mobile users manage their tasks by smart contract and bargain price with distributed *** this way,resource could be exploited better,and the market could be more ***’s more,the paper analyzes Walrasian Equilibrium(WE)in the market,and details how to deploy MCS in *** results shows that Equilibrium could be found.

关键词： mobile crowdsensing incentive mechanism blockchain Walrasian Equilibrium

Persistent alterations in gray matter in COVID-19 patients experiencing sleep disturbances:a 3-month longitudinal study

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Neural Regeneration Research 2025年第10期20卷 3013-3024页

作者： Kaixuan Zhou Gaoxiong Duan Ying Liu Bei Peng Xiaoyan Zhou Lixia Qin Lingyan Liang Yichen wei Qingping Zhang Xiaocheng Li Haixia Qin Yinqi Lai Yian Lu yan Zhang Jiazhu Huang Jinli Huang Yinfei Ouyang Bolin Bin Mingming Zhao Jun Liu Jianrong yang Demao Deng Guangxi Key Laboratory of Special Biomedicine School of MedicineGuangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology the People’s Hospital of Guangxi Zhuang Autonomous RegionGuangxi Academy of Medical SciencesNanningGuangxi Zhuang Autonomous RegionChina Department of Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Guangxi Clinical Research Center for Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina

Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 *** studies have demonstrated abnormal brain structures in patients with sleep disturbances who have recovered from coronavirus disease 2019(COVID-19).However,neuroimaging studies on sleep disturbances caused by COVID-19 are scarce,and existing studies have primarily focused on the long-term effects of the virus,with minimal acute phase *** a result,little is known about the pathophysiology of sleep disturbances in the acute phase of *** address this issue,we designed a longitudinal study to investigate whether alterations in brain structure occur during the acute phase of infection,and verified the results using 3-month follow-up data.A total of 26 COVID-19 patients with sleep disturbances(aged 51.5±13.57 years,8 women and 18 men),27 COVID-19 patients without sleep disturbances(aged 47.33±15.98 years,9 women and 18 men),and 31 age-and gender-matched healthy controls(aged 49.19±17.51 years,9 women and 22 men)were included in this *** COVID-19 patients with sleep disturbances were included in a longitudinal *** found that COVID-19 patients with sleep disturbances exhibited brain structural changes in almost all brain *** cortical thicknesses of the left pars opercularis and left precuneus were significantly negatively correlated with Pittsburgh Sleep Quality Index ***,we observed changes in the volume of the hippocampus and its subfield regions in COVID-19 patients compared with the healthy *** 3-month follow-up data revealed indices of altered cerebral structure(cortical thickness,cortical grey matter volume,and cortical surface area)in the frontal-parietal cortex compared with the baseline in COVID-19 patients with sleep *** findings indicate that the sleep disturbances patients had altered morphology in the cortical an

关键词： brain structure cortical gray matter volume cortical surface area cortical thickness hippocampus magnetic resonance imaging Pittsburgh Sleep Quality Index severe acute respiratory syndrome coronavirus 2 infections sleep disturbances sub-cortical volume

Hepatocytes targeting of cationic liposomes modified with soybean sterylglucoside and polyethylene glycol

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World Journal of Gastroenterology 2005年第32期11卷 4947-4952页

作者： Xian-Rong Qi Wen-wei yan jing Shi Department of Pharmaceutics School of Pharmaceutical Sciences Peking University Beijing 100083 China

AIM： In this study, a hepatocyte-specific targeting technology was developed by modifying cationic liposomes with soybean sterylglucoside （SG） and polyethylene glycol （PEG）（C/SG/ PEG-liposomes）. METHODS： The liposomal transfection efficiencies in HepG2 2.2.15 cells were estimated with the use of fluorescein sodium （FS） as a model drug, by flow cytometry. The antisense activity of C/SG/PEG-liposomes entrapped antisense oligonucleotides （ODN） was determined as HBsAg and HBeAg in HepG2 2.2.15 cells by ELISA. The liposome uptake by liver and liver cells in mice was carried out after intravenous injection of 3H-labeled liposomes. RESULTS： C/SG-liposomes entrapped FS were effectively transfected into HepG2 2.2.15 cells in vitro. C/SG/PEG-Iiposomes entrapped ODN, reduced the secretion of both HBsAg and HBeAg in HepG2 2.2.15 cells when compared to free ODN. After in vivo injection of ^3H-labeled C/SG/PEG-liposomes, higher radiation accumulation was observed in the hepatocytes than non-parenchymal cells of the liver. CONCLUSION： C/SG/PEG-liposomes mediated gene transfer to the liver is an effective gene-delivery method for hepatocytes-specific targeting, which appears to have a potential for gene therapy of HBV infections.

关键词： Hepatocytes targeting Cationic liposomes Soybean sterylglucoside

Possible evidence of destroying small PAH particles by radiation from AGNs

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Research in Astronomy and Astrophysics 2015年第2期15卷 199-206页

作者： Qi-Chen Feng jing Wang Jian-yan wei National Astronomical Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences

The issue of destroying small polycyclic aromatic hydrocarbon （PAH） par- ticles by radiation from AGNs is examined through optical narrow-emission line ra- tios of a sample of type II AGNs. We find that narrow-line ratios [OI]λ6300/Ha and [SII]λ6716, λ6731/Hα have prominent correlations with the PAH 11.3/7.7 ratio in our selected sample of AGNs. Because of the marginal （and in some cases no） dependence of the PAH ratio on the gas metallicity, a possible explanation for the correlations is the destruction of small PAH particles by the hard ionizing field associated with the AGNs.

关键词： infrared: ISM quasars: emission lines galaxies: active galaxies: AGN methods: statistical

Extending the Eigenvector 1 space to the optical variability of quasars

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Chinese Journal of Astronomy and Astrophysics 2009年第5期9卷 529-537页

作者： Yu-Feng Mao jing Wang Jian-yan wei National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

We introduce a new physical parameter, the optical variability amplitude, to the well-established Eigenvector 1 space of quasars and test a sample of long-term B- band light curves of 42 Palomar-Green quasars monitored by Giveon et al. We find that the optical variability amplitude strongly correlates with the intensity ratio of FeⅡ to Hβ, Hβ width and peak luminosity at 5007A. We briefly discuss the physical meaning of our findings and suggest that the Eddington ratio may be a key factor in determining a quasar＇s variability.

关键词： galaxies active -- quasars general

Fragmentation of N2 in 410 nm Intense Femtosecond Laser Field

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Chinese Journal of Chemical Physics 2009年第1期22卷 1-6页

作者： wei Guo jing-yi Zhu yan-qiu Wang Li Wang State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China Graduate School of Chinese Academy of Sciences Beijing 100049 China

Fragmentations of N2 in linearly polarized femtosecond 410 and 820 nm intense laser fields were studied by using the velocity mapping technique. Different behaviors of N2 at 410 and 820 nm were observed. Both the kinetic energy distributions and angular distributions of fragment ions in 410 nm field show weak dependency on laser intensities in the non- saturation regime, in contrast to the case in 820 nm. Different excited electronic states, i.e., non-Coulombic potentials populated via vertical＇excitation, are suggested to play crucial roles in fragmentations at short wavelength.

关键词： Velocity mapping Non-Coulombic fragmentation Energy distribution Angular distribution

Dispersion features of pollutants in a compound channel with vegetated floodplains

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Journal of Hydrodynamics 2022年第6期34卷 1095-1105页

作者： yan-fang Zhao jing-jing Fan wei-jie Wang Han-qing Zhao Fei Dong Zhen Han Shi-yan Wang School of Water Conservancy and Hydroelectric Power Hebei University of EngineeringHandan056038China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing100038China China Three Gorges Corporation Wuhan430010China National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Nanjing210024China

The planting of the vegetation on the floodplain helps the ecological restoration,which is the main form of the river’s ecological ***,the current research of the river dynamics focuses on the water movement under a compound channel with the vegetated *** simulated vegetation species are selected in this paper for the flume simulation experiments of the floodplain vegetation,and the compound channel is divided into three subregions in the transverse *** Navier-Stokes equation and the eddy viscosity theory are applied to obtain the transverse distribution of the depth-averaged velocity and the results agree well with the experimental *** paper proposes a new method based on the analytical solution of the flow velocity distribution to calculate the average flow velocity in each *** results can effectively simulate the average flow velocity of the measured *** description of the pollutant transport processes in a moving stream requires a refined determination of the dispersion coefficients in the compound *** process of the pollutant concentrations in each zone and the reasons for their occurrence are elucidated on the basis of the experimental ***,the measured values of the longitudinal dispersion coefficients are obtained by the“routing procedure,”and a two-zone model of the pollutant dispersion is constructed on the basis of the hydrodynamic *** prediction method for the longitudinal dispersion coefficients is also *** the predicted and measured section average flow velocities to the two-zone model to predict the longitudinal dispersion coefficient,and the average relative errors are only 4.17%,7.15%,*** result indicates that the two-zone model can effectively predict the longitudinal dispersion *** calculation methods for the longitudinal dispersion coefficients from—various studies are *** results reveal that the p

关键词： Compound channel floodplain vegetation velocity distribution pollutant transport dispersion coefficient