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One-step controlled electrodeposition nickel sulfides heterointerfaces favoring the desorption of hydroxyl groups for efficient hydrogen generation

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Rare Metals 2024年第9期43卷 4377-4386页

作者： Ru-Chun Li Xin-Yue Zhang Ze-Yue Qu Feng-Yi Liu quan-qing xu Zhao-Xia Hu Jing-Wei Li Mohamed-Nawfal Ghazzal Jin-Li Yu Faculty of Chemistry and Chemical Engineering Yunnan Normal University Foshan Gaoke Hechuang Technology Co. Ltd. School of Chemistry and Chemical Engineering Guangzhou University Universite′Paris-Saclay UMR 8000 CNRSInstitut de Chimie Physique Department of Chemistry City University of Hong Kong

The heterointerface engineering involving different components or phases represents a desirable strategy for enhancing the sluggish kinetics of hydrogen evolution reaction （HER）.However,constructing desired heterointerfaces and elucidating the reaction mechanisms on the interface remains a considerable *** this work,we propose a straightforward electrochemical synthesis strategy to prepare the nickel sulfide-based heterointerfaces for *** mechanism of electrochemical synthesis is revealed,wherein metal-thiourea species can be formed at the cathode potential and subsequently oxidized to nickel sulfides at the anode *** this mechanism,a range of nickel sulfides,including NiS,Ni3S2/NiS,Ni/Ni3S2and Ni3S2,have been successfully synthesized by tuning the potential range of cyclic *** these,the obtained Ni3S2/NiS@CC（CC:carbon cloth） exhibits the smallest overpotential of84 mV at 10 mA·cm-2and high *** calculations further reveal that the combination of NiS and Ni3S2induces electron redistribution at the interface,and thus the Volmer process is effectively promoted with faster water dissociation and OH desorption ***,the simplicity method coupled with a clear synthesis mechanism and outstanding HER performance highlights its promising potential for practical applications.

关键词： Electrochemical synthesis Heterointerfaces Hydrogen evolution reaction OH desorption kinetics

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CRL： Efficient Concurrent Regeneration Codes with Local Reconstruction in Geo-Distributed Storage Systems

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Journal of Computer Science & Technology 2018年第6期33卷 1140-1151页

作者： quan-qing xu Wei-Ya Xi Khai Leong Yong Chao Jin Institute of High Performance Computing Agency for Science Technology and Research Singapore 138632 Singapore Data Storage Institute Agency for Science Technology and Research Singapore 138632 Singapore Institute for Infocomm Research Agency for Science Technology and Research Singapore 138632 Singapore

As a typical erasure coding choice, Reed-Solomon （RS） codes have such high repair cost that there is a penaltyfor high reliability and storage efficiency, thereby they are not suitable in geo-distributed storage systems. We present anovel family of concurrent regeneration codes with local reconstruction （CRL） in this paper. The CRL codes enjoy threebenefits. Firstly, they are able to minimize the network bandwidth for node repair. Secondly, they can reduce the numberof accessed nodes by calculating parities from a subset of data chunks and using an implied parity chunk. Thirdly, they arefaster than existing erasure codes for reconstruction in geo-distributed storage systems. In addition, we demonstrate howthe CRL codes overcome the limitations of the Reed-Solomon codes. We also illustrate analytically that they are excellent inthe trade-off between chunk locality and minimum distance. Furthermore, we present theoretical analysis including latencyanalysis and reliability analysis for the CRL codes. By using quantity comparisons, we prove that CRL（6, 2, 2） is only0.657x of Azure LRC（6, 2, 2）, where there are six data chunks, two global parities, and two local parities, and CRL（10,4, 2） is only 0.656x of HDFS-Xorbas（10, 4, 2）, where there are 10 data chunks, four local parities, and two global paritiesrespectively, in terms of data reconstruction times. Our experimental results show the performance of CRL by conductingperformance evaluations in both two kinds of environments： 1） it is at least 57.25% and 66.85% more than its competitorsin terms of encoding and decoding throughputs in memory, and 2） it has at least 1.46x and 1.21x higher encoding anddecoding throughputs than its competitors in JBOD （Just a Bunch Of Disks）. We also illustrate that CRL is 28.79% and30.19% more than LRC on encoding and decoding throughputs in a geo-distributed environment.

关键词： concurrent regeneration code local reconstruction geo-distributed storage system

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Early and delayed castrations confer a similar survival advantage in TRAMP mice

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Asian Journal of Andrology 2009年第3期11卷 291-297页

作者： Zai-Xian Zhang qing-quan xu Xiao-Bo Huang Ji-Chuan Zhu Xiao-Feng Wang Department of Urology Peking University People＇s Hospital Beijing 100044 China

The most appropriate time to introduce androgen deprivation therapy for prostate cancer remains controversial. Our aim was to evaluate the effects of early versus delayed surgical castration on prostate cancer progression and survival in the transgenic adenocarcinoma of the mouse prostate （TRAMP） model. TRAMP mice were randomly divided into three groups： the early castration group （on which castration was performed at the age of 4 weeks）, the delayed castration group （on which castration was performed when abdominal tumours could be palpated）, and the sham-castrated group. Mice were monitored daily throughout their lives until cancer-related death or the develop- ment of an obviously moribund appearance, at which time the individual mouse was killed. Androgen receptor expression in prostate tumours was also evaluated. The results shows that the average lifespan in early castration, delayed castration and sham-castrated groups were 54.1 weeks, 59.9 weeks and 39.1 weeks, respectively. Both early castration and delayed castration conferred a statistically significant survival advantage when compared with the sham-castrated group （P 〈 0.001）. However, the difference in lifespan between the early castration group and the delayed castration group was not statistically significant （P = 0.85）. The increase in lifespan in the TRAMP mice that received either early or delayed castration correlated with lower G/B value （genitourinary tract weight/body weight） at death than the sham-castrated mice. In conclusion, early and delayed castrations in TRAMP mice pro- longed survival to a similar extent. This finding may provide a guide for clinical practice in prostate cancer therapy.

关键词： castration prostate cancer survival TRAMP

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Multimodal magnetic resonance imaging for assessing lacunar infarction after proximal middle cerebral artery occlusion in a canine model

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Chinese Medical Journal 2013年第2期126卷 311-317页

作者： LU Shan-shan LIU Sheng ZU qing-quan xu Xiao-quan WANG Jian-wei YU Jing SUN Lei SHI Hai-bin Department of Radiology the First Affiliated Hospital of NanjingMedical University Nanjing Jiangsu 210029 China

Background A new lacunar infarction model was recently established in beagle dogs through proximal middle cerebral artery （MCA） occlusion by thrombus. This study aimed to characterize the model by multimodal magnetic resonance imaging （MRI） and to investigate its potential role for the future stroke research. Methods The left proximal MCA was embolized with an autologous thrombus in six beagles. Diffusion-weighted imaging （DWI） and T2-weighted imaging （T2Wl） were performed every half hour during the first six hours after occlusion, followed by three time points at 12 hours, 24 hours, and one week. Perfusion-weighted imaging （PWI） and magnetic resonance angiography （MRA） were carried out at six hours, 24 hours and one week. The PWI-DWI mismatch ratio was defined as （PWI-DWl）/DWl ischemic volume. Results Lacunar infarcts induced by MCA occlusion were located in the left caudate nucleus and internal capsule. All the lesions could be detected within two hours by DWI. Lesion volume on DWl increased in a time dependent manner, from （87.19±67.16） mm3 at one hour up to （368.98±217.05） mm3 at 24 hours （P=0.009）, while that on PWl gradually decreased from （7315.00±2054.38） mm3at six hours to （4900.33±1319.71） mm3 at 24 hours and （3334.33±1195.11） mm3 at one week （P=0.002）. The mismatch ratio was 41.93±22.75 at six hours after ischemia, showing ＂extensive mismatch＂, and decreased to 18.10±13.74 at 24 hours （P=0.002）. No MCA recanalization was observed within 24 hours after MCA occlusion. Conclusions Lacunar infarction induced by proximal MCA occlusion could be detected early by DWl and was characterized by extensive PWI-DWl mismatch. Multimodal MRI is useful to demonstrate the natural evolution of PWI-DWl mismatch. This ischemic model could be further used for investigating early thrombolysis in lacunar stroke showing extensive mismatch.

关键词： animal model middle cerebral artery occlusion lacunar infarction magnetic resonance imaging

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Andrology in China： current status and 10 years＇ progress

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Asian Journal of Andrology 2011年第4期13卷 512-518页

作者： Kai Hong qing-quan xu Yong-Ping Zhao Yi-Qun Gu Hui Jiang Xiao-Feng Wang Ji-Chuan Zhu Urology Department Peking University 3rd Hospital Beijing 100191 China Department of Urology Peking University People＇s Hospital Beijing 100044 China Department of Male Clinic Research National Research Institute for Family Planning Beijing 100081 China

Andrology has a long history in traditional Chinese medicine. There are records of male sexual health, male sexual dysfunction and male infertility from over thousands of years ago. Modern andrology in China had a late start, with the Chinese Androlo~ Association founded in 1995. Within last decade, andrology in China has grown rapidly. In this review article, we summarized the progress of androlo~ in last 10 years and outlined the current status of Chinese andrology with a special focus on progress in male erectile dysfunction, prostate diseases, male infertility and male hormonal contraception.

关键词： andrology benign prostatic hyperplasia Chinese contraception erectile dysfunction male infertility prostate cancer prostatitis

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A survey on facial image deblurring

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Computational Visual Media 2024年第1期10卷 3-25页

作者： Bingnan Wang Fanjiang xu quan Zheng Institute of Software Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

When a facial image is blurred,it significantly affects high-level vision tasks such as face *** purpose of facial image deblurring is to recover a clear image from a blurry input image,which can improve the recognition accuracy,***,general deblurring methods do not perform well on facial ***,some face deblurring methods have been proposed to improve performance by adding semantic or structural information as specific priors according to the characteristics of the facial *** this paper,we survey and summarize recently published methods for facial image deblurring,most of which are based on deep ***,we provide a brief introduction to the modeling of image ***,we summarize face deblurring methods into two categories:model-based methods and deep learning-based ***,we summarize the datasets,loss functions,and performance evaluation metrics commonly used in the neural network training *** show the performance of classical methods on these datasets and metrics and provide a brief discussion on the differences between model-based and learning-based ***,we discuss the current challenges and possible future research directions.

关键词： facial image deblurring model-based deep learning-based semantic or structural prior

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Improvement for creep strength of a second-generation single crystal superalloy by design of heat treatments

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Rare Metals 2024年第1期43卷 342-350页

作者： Wan-Shun Xia Xin-Bao Zhao Jia-Chen xu quan-Zhao Yue qing-qing Ding Huan-Chang Duan Yue-Feng Gu Hong-Bin Bei Ze Zhang Institute of Superalloys Science and Technology School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China State Key Laboratory of Silicon and Advanced Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China

Design of heat treatments is related to the key technology for development of nickel-based single crystal superalloys(Ni-SXs). Based on the full understanding of the solidification characteristics, this work applies optimization design of heat treatments for a second-generation Ni-SX. Microstructure evolution and creep properties are compared in the material under conventional/standard(Std.) and optimized(Opt.) treatments. For the Std. sample,strong dendritic segregations determine inconsistent microstructure evolution in the dendritic(D) and interdendritic region(ID), while the latter serves as weak area to have the prior microcrack initiation, damaging overall performance of the alloy. The Opt. treatment applies higher homogenization temperature, leading to overall reduced segregations, while not inducing incipient melting. A lower temperature of first-step ageing is used to lower the size ofγ'particles. These help to form the more uniform microstructure in dendritic and interdendritic region and relieve the inconsistent microstructure evolution. The balanced local strength makes ID no longer as the weak area,thus restricting microcrack initiation. Great improvement of high temperature and low stress property is obtained by this progress, leading to the pronounced increase of creep rupture life under 1100 °C/140 MPa.

关键词： Single crystal superalloy Heat treatment Segregation Solidification Creep property

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Studies on plasma endothelin changes in varicocele patients

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Asian Journal of Andrology 1999年第3期1卷 159-160页

作者： qing-quan xu Ji-Chuan ZHU Hu JIANG Xiao-Feng WANG Shu-Kun HOU qing-Li LIU Department of Urology, People’s Hospital, Beijing Medical University, Beijing 100011, China Department of Urology People's Hospital Beijing Medical University Beijing 100011 China

Aim: To investigate the possible role endothelin may play in the pathogenesis of varicocele and varicocele-induced infer-tility. Methods: In varicocele patients, radioimmunoassay is used to determine the blood endothelin concentration inthe spermatic vein and the antecubital vein separately. Results: The blood endothelin concentration of the spermaticvein (66.8±23.5 pg/mL) was significantly higher (P <0.05) than that of the antecubital vein (55.3±25.3 pg/mL).The endothelin concentration in the spermatic vein in Grade Ⅱ varicocele patients was not significantly different from thatin Grade Ⅲ patients ( P = 0.87). Conclusion: The higher blood endothelin level in the spermatic vein may indicate theinvolvement of endothelin in the pathophysiology of varicocele and varicocele-induced infertility. (Asian J Androl 1999Sep ; 1: 159 - 160)

关键词： endothelin varicocele infertility

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Rheological Behaviors of Polymers with Nanoparticles Tethered at Each End

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Chinese Journal of Polymer Science 2024年第3期42卷 400-406,I0009页

作者： Song-Qi Zhang Wen-qing Wang Jia-Ping Lin Li-quan Wang Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

The polymer with nanoparticles tethered at each end is a unique model for unraveling the effect of chain ends on the polymer dynamics. We investigated the rheological behavior of this kind of polymer by using nonequilibrium molecular dynamics simulation. The effect of polymer lengths and nanoparticle radii on the complex moduli and viscosity was examined. The dependence of complex moduli on the frequency becomes less pronounced as the polymer is short or the nanoparticle is large. The shear thinning behavior was revealed for these systems, and the scaling exponent of complex viscosity with respect to the frequency was found to change from-1/2 to-3/4 as the polymer shortens or the nanoparticle enlarges. The rheological behavior was further explained by analyzing the mean square distance of nanoparticles. The simulation results were compared with the existing experimental finding, showing an agreement. The work provides information for understanding the chain end effect on polymer rheology.

关键词： Polymer rheology Modulus Viscosity Molecular dynamics

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Nonlinear Extrapolation Estimates of π

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 91-108页

作者： Wen-qing xu Sha-sha Wang Da-chuan xu Beijing Institute for Scientific and Engineering Computing Beijing University of TechnologyBeijing100124China Department of Mathematics and Statistics California State UniversityLong BeachCalifornia90840USA Department of Mathematics and Physics Shijiazhuang Tiedao UniversityShijiazhuang050043China

The classical Archimedean approximation of π uses the semiperimeter or area of regular polygons inscribed in or circumscribed about a unit circle in R~2 and it is well-known that by using linear combinations of these basic estimates,modern extrapolation techniques can greatly speed up the approximation ***,when n vertices are randomly selected on the circle,the semiperimeter and area of the corresponding random inscribed and circumscribing polygons are known to converge to π almost surely as n→∞,and by further applying extrapolation processes,faster convergence rates can also be achieved through similar linear combinations of the semiperimeter and area of these random *** this paper,we further develop nonlinear extrapolation methods for approximating π through certain nonlinear functions of the semiperimeter and area of such *** focus on two types of extrapolation estimates of the forms χ_n=S_n~αA_n~β and Y_n(p)=(αS_n~p+βA_n~p)~(1/p) where α+β=1,p≠0,and Sn and An respectively represents the semiperimeter and area of a random n-gon inscribed in the unit circle in R~2,and Xn may be viewed as the limit of Y_n(p) when p→*** deriving probabilistic asymptotic expansions with carefully controlled error estimates for Xn and Y_n(p),we show that the choice α=4/3,β=-1/3 minimizes the approximation error in both cases,and their distributions are also asymptotically normal.

关键词： Archimedean polygons random polygons approximations ofπ extrapolation processes asymptotic convergence

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