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21篇 您的检索式:作者名="Zhang Xuyu"
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1Applications of graphene-based materials in environmental protection and detection显示文摘Many efficient adsorbents and sensors based on graphene and functionalized graphene have been constructed for the removal and detection of environmental pollutants due to its unique physicochemical properties. In this article, recent research achievements are reviewed on the application of graphene-based materials in the environmental protection and detection. For environmental protection, modified graphene can adsorb heavy metal ions in a high efficiency and selectivity, and thus reduces them to metals for recycling. High adsorption capacity of graphene-based materials to kinds of organic pollutants in water was also presented. Several graphene-based sensors with high limit of detection were reported to detect heavy metal ions, toxic gases and organic pollutants in environment. Finally, a perspective on the future challenge of adsorbents and detection devices based on graphene is given.Lü MeiJiao LI Jing YANG XuYu ZHANG ChangAn YANG Jia HU Hao WANG XianBao 2013Chinese Science Bulletin2013,58,22:9
2Factors influencing the natural regeneration of arrow bamboo in giant panda habitat of the north Minshan Mountains,southwestern China显示文摘To determine the effects of eco-factors on the regeneration of arrow bamboo in giant panda habitat,a field study was conducted in the Baozuo and Gonggangling Nature Reserves,Sichuan Province,China.A total of 183 quadrats(10 m×10 m) and 717 small quadrats(1 m×1 m) were investigated within the study site.Bamboo seedling density was used as an indicator of natural regeneration.Twelve factors were measured,which included topography and forest factors(elevation,slope aspect,slope degree,slope position,canopy cover,and shrub cover) and microhabitat factors(upper vegetation cover,herb cover,litter layer cover,moss cover,moss thickness,and dead bamboo density).A One-Way ANOVA was used to analyze the effects of topography and forest factors on seedling density,and a GLM(Generalized Linear Model) procedure was performed to examine the relationship between seedling density and microhabitat factors.The results indicated that elevation and canopy cover had highly significant effects on seedling density:bamboo seedling density was highest and showed the best regeneration at middle elevations(2800-3000 m) and under medium to medium-high canopy cover.Moss thickness,moss cover,and dead bamboo density were the most important microhabitat factors influencing the natural regeneration of bamboo:seedling density increased with increasing moss cover and moss thickness and decreased with increasing dead bamboo density.We propose that removal of dead bamboo and controlling grazing activities may accelerate the process of bamboo regeneration.LI Bo ZHANG Man ZHONG Xue MOERMOND Timothy RAN JiangHong YANG XuYu 2013Chinese Science Bulletin2013,58,17:4
3A wave of Foxp3^(+) regulatory T cell accumulation in the neonatal liver plays unique roles in maintaining self-tolerance显示文摘Newborn animals require tightly regulated local and systemic immune environments to govern the development and maturation of multiple organs/tissues even though the immune system itself is far from mature during the neonatal period.Regulatory T cells(Tregs)are essential for maintaining immune tolerance/homeostasis and modulating inflammatory responses.The features of Tregs in the neonatal liver under steady-state conditions are not well understood.The present study aimed to investigate the phenotype,functions,and significance of neonatal Tregs in the liver.We found a wave of thymus-derived Treg influx into the liver during 1–2 weeks of age.Depletion of these Tregs between days 7 and 11 after birth rapidly resulted in Th1-type liver inflammation and metabolic disorder.More Tregs in the neonatal liver than in the spleen underwent MHC II-dependent activation and proliferation,and the liver Tregs acquired stronger suppressive functions.The transcriptomic profile of these neonatal liver Tregs showed elevated expression of PPARγand T-bet and features of Tregs that utilize lipid metabolic machinery and are capable of regulating Th1 responses.The accumulation of Tregs with unique features in the neonatal liver is critical to ensure self-tolerance and liver maturation.Mingyang Li Weijia Zhao Yifan Wang Lixue Jin Gaowen Jin Xiuyuan Sun Wei Wang Ke Wang Xi Xu Jie Hao Rong Jin Wenxian Fu Ying Sun Yingjun Chang Xiaojun Huang Xuyu Zhou Hounan Wu Kunshan Zhang Qing Ge 2020Cellular & Molecular Immunology2020,17,5:4
4Microsatellite variability reveals high genetic diversity and low genetic differentiation in a critical giant panda population显示文摘Jiandong YANG Zhihe ZHANG Fujun SHEN Xuyu YANG Liang ZHANG Limin CHEN Wenping ZHANG Qing ZHU Rong HOU 2011Current Zoology2011,57,6:3
5Effects and mechanisms of store-operated calcium channel blockade on hepatic ischemia-reperfusion injury in rats显示文摘AIM:To further investigate the important role of store-operated calcium channels (SOCs) in rat hepatocytes and to explore the effects of SOC blockers on hepatic ischemia-reperfusion injury (HIRI).METHODS:Using freshly isolated hepatocytes from a rat model of HIRI (and controls),we measured cyto-solic free Ca 2+ concentration (by calcium imaging),net Ca 2+ fluxes (by a non-invasive micro-test technique),the SOC current (I SOC ;by whole-cell patch-clamp record-ing),and taurocholate secretion [by high-performance liquid chromatography and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays].RESULTS:Ca 2+ oscillations and net Ca 2+ fluxes medi-ated by Ca 2+ entry via SOCs were observed in rat he-patocytes.I SOC was significantly higher in HIRI groups than in controls (57.0 ± 7.5 pA vs 31.6 ± 2.7 pA,P <0.05) and was inhibited by La 3+.Taurocholate secretion by hepatocytes into culture supernatant was distinctly lower in HIRI hepatocytes than in controls,an effect reversed by SOC blockers.CONCLUSION:SOCs are pivotal in HIRI.SOC blockers protected against HIRI and assisted the recovery of se-cretory function in hepatocytes.Thus,they are likely to become a novel class of effective drugs for prevention or therapy of HIRI patients in the future.Li-Jie Pan,Zi-Chao Zhang,Zhen-Ya Zhang,Zong-Ming Zhang,Department of General Surgery,Digestive Medical Center,The First Affiliated Hospital,School of Medicine,Tsinghua University,Beijing 100016,China Wen-Jun Wang,Yue Xu,Xuyue (Beijing) Science and Technology Co.,Ltd.,Haidian District,Beijing 100080,China 2012World Journal of Gastroenterology2012,18,4:3
6Modulation of orbital angular momentum on the propagation dynamics of light fields显示文摘Optical vortices carrying orbital angular momentum(OAM)have attracted extensive attention in recent decades because of their interesting applications in optical trapping,optical machining,optical communication,quantum information,and optical microscopy.Intriguing effects induced by OAMs,such as angular momentum conversion,spin Hall effect of light(SHEL),and spin– orbital interaction,have also gained increasing interest.In this article,we provide an overview of the modulations of OAMs on the propagation dynamics of scalar and vector fields in free space.First,we introduce the evolution of canonical and noncanonical optical vortices and analyze the modulations by means of local spatial frequency.Second,we review the Pancharatnam–Berry(PB)phases arising from spin–orbital interaction and reveal the control of beam evolution referring to novel behavior such as spindependent splitting and polarization singularity conversion.Finally,we discuss the propagation and focusing properties of azimuthally broken vector vortex beams.Peng LI Sheng LIU Yi ZHANG Lei HAN Dongjing WU Huachao CHENG Shuxia QI Xuyue GUO Jianlin ZHAO 2019Frontiers of Optoelectronics2019,12,1:2
7Seasonal Variability of Phytoplankton Community Structure in Relation to Different Nitrogen-Phosphorus Ratios in the Southern Coastal Waters of Zhejiang, China显示文摘With the rapid development of economy and increase of population in the drainage areas,the nutrient loading has increased dramatically in the Changjiang estuary and adjacent coastal waters.To properly assess the impact of nutrient enrichment on phytoplankton community,seasonal microcosm experiments were conducted during August 2010 July 2011 in the coastal waters of Zhejiang Province.The results of the present study indicated that the chl a concentration,cell abundance,diversity indices,species composition and community succession of the phytoplankton varied significantly with different N/P ratios and seasons.Higher growth was observed in the 64:1(spring),32:1(summer),16:1(autumn)and 128:1,256:1(winter)treatments,respectively.The values of Shannon-Wiener index(H′)and Pielou evenness index(J)were lower in the 8:1 and 16:1 treatments in autumn test,while H'value was higher in the 128:1 and 8:1 treatments in winter test.A definite community succession order from diatoms to dinoflagellates was observed in the autumn and winter tests,while the diatoms dominated the community throughout the culture in the spring and summer tests.HUANG Wei ZHU Xuyu CHEN Quanzhen HE Qing LIAO Yibo DU Ping ZHANG Peng ZENG Jiangning 2013Journal of Ocean University of China2013,12,4:2
8RFHUI:an RFID based human-unmanned aerial vehicle interaction system in an indoor environment显示文摘In this paper,we present an RFID based human and Unmanned Aerial Vehicle(UAV)Interaction system,termed RFHUI,to provide an intuitive and easy-to-operate method to navigate a UAV in an indoor environment.It relies on the passive Radio-Frequency IDentification(RFID)technology to precisely track the pose of a handheld controller,and then transfer the pose information to navigate the UAV.A prototype of the handheld controller is created by attaching three or more Ultra High Frequency(UHF)RFID tags to a board.A Commercial Off-The-Shelf(COTS)RFID reader with multiple antennas is deployed to collect the observations of the tags.First,the precise positions of all the tags can be obtained by our proposed method,which leverages a Bayesian filter and Channel State Information(CSI)phase measurements collected from the RFID reader.Second,we introduce a Singular Value Decomposition(SVD)based approach to obtain a 6-DoF(Degrees of Freedom)pose of the controller from estimated positions of the tags.Furthermore,the pose of the controller can be precisely tracked in a real-time manner,while the user moves the controller.Finally,control commands will be generated from the controller's pose and sent to the UAV for navigation.The performance of the RFHUI is evaluated by several experiments.The results show that it provides precise poses with 0.045m mean error in position and 2.5∘mean error in orientation for the controller,and enables the controller to precisely and intuitively navigate the UAV in an indoor environment.Jian Zhang Zhitao Yu Xiangyu Wang Yibo Lv Shiwen Mao Senthilkumar CG.Periaswamy Justin Patton Xuyu Wang 2020Digital Communications and Networks2020,6,1:1
9大熊猫保护区的生态系统服务价值显示文摘文章简介全球生态系统服务价值估计每年为125万亿美元,相似的国家和区域层面的评估也显示生态系统服务价值足以支撑我们的生活。所有的生态系统服务价值评估都肯定了生物多样性的重要作用.魏辅文 Robert Costanza Qiang Dai Natalie Stoeckl Xiaodong Gu Stephen Farber Yonggang Nie Ida Kubiszewski Yibo Hu Ronald Swaisgood Xuyu Yang Michael Bruford Youping Chen Alexey Voinov Dunwu Qi Megan Owen Li Yan Daniel C.Kenny Zejun Zhang Rong Hou Shiwei Jiang Hongbo Liu Xiangjiang Zhan Li Zhang Biao Yang Lianjun Zhao Xiaoguang Zheng Wenliang Zhou Yali Wen Heran Gao Wen Zhang 2019科学新闻2019,0,2:1
10Rational construction of Ag@MIL-88B(V)-derived hierarchical porous Ag-V_(2)O_(5) heterostructures with enhanced diffusion kinetics and cycling stability for aqueous zinc-ion batteries显示文摘With the advantages of the multiple oxidation states and highly open crystal structures,vanadium-based composites have been considered as the promising cathode materials for aqueous zinc-ion batteries(ZIBs).However,the inherent inferior electrical conductivity,low specific surface area,and sluggish Zn^(2+)diffusion kinetics of the traditional vanadium-based oxides have greatly impeded their development.Herein,a novel hierarchical porous spindle-shaped Ag-V_(2)O_(5) with unique heterostructures was rationally designed via a simple MOF-assisted synthetic method and applied as stable cathode for aqueous ZIBs.The high specific surface area and hierarchically porous superstructures endowed Ag-V_(2)O_(5) with sufficient electrochemical active sites and shortened the diffusion pathways of Zn^(2+),which was beneficial to accelerate the reversible transport of Zn^(2+)and deliver a high specific capacity(426 mA h g^(-1) at 0.1 A g^(-1) and 96.5%capacity retention after 100 cycles).Meanwhile,the self-built-in electric fields at the heterointerface of Ag-V_(2)O_(5) electrode could strengthen the synergistic coupling interaction between Ag and V_(2)O_(5),which can effectively enhance the electric conductivity and maintain the structural integrity,resulting in superb rate capability(326.1 mA h g^(-1) at 5.0 A g^(-1))and remarkable cycling stability(89.7%capacity retention after 2000 cycles at 5.0 A g^(-1)).Moreover,the reversible Zn^(2+)storage mechanism was further investigated and elucidated by kinetics analysis and DFT calculations.Yibo Zhang Zhihua Li Liangjun Gong Xuyu Wang Peng Hu Jun Liu 2023Journal of Energy Chemistry2023,,2:1
11An Encrypted Image Retrieval Method Based on SimHash in Cloud Computing显示文摘With the massive growth of images data and the rise of cloud computing that can provide cheap storage space and convenient access,more and more users store data in cloud server.However,how to quickly query the expected data with privacy-preserving is still a challenging in the encryption image data retrieval.Towards this goal,this paper proposes a ciphertext image retrieval method based on SimHash in cloud computing.Firstly,we extract local feature of images,and then cluster the features by K-means.Based on it,the visual word codebook is introduced to represent feature information of images,which hashes the codebook to the corresponding fingerprint.Finally,the image feature vector is generated by SimHash searchable encryption feature algorithm for similarity retrieval.Extensive experiments on two public datasets validate the effectiveness of our method.Besides,the proposed method outperforms one popular searchable encryption,and the results are competitive to the state-of-the-art.Jiaohua Qin Yusi Cao Xuyu Xiang Yun Tan Lingyun Xiang Jianjun Zhang 2020Computers, Materials & Continua2020,,4:1
12Carotid atherosclerosis and ischemic cerebrovascular disease显示文摘Xuyu Wu Tang Hongyuan Zhang Ling 2011Chinese Journal of Cerebrovas- cular Diseases2011,4,3:1
13Beauvericin counteracted multi-drug resistant Candida albicans by blocking ABC transporters显示文摘Multi-drug resistance of pathogenic microorganisms is becoming a serious threat,particularly to immunocompromised populations.The high mortality of systematic fungal infections necessitates novel antifungal drugs and therapies.Unfortunately,with traditional drug discovery approaches,only echinocandins was approved by FDA as a new class of antifungals in the past two decades.Drug efflux is one of the major contributors to multi-drug resistance,the modulator of drug efflux pumps is considered as one of the keys to conquer multi-drug resistance.In this study,we combined structure-based virtual screening and whole-cell based mechanism study,identified a natural product,beauvericin(BEA)as a drug efflux pump modulator,which can reverse the multi-drug resistant phenotype of Candida albicans by specifically blocking the ATP-binding cassette(ABC)transporters;meantime,BEA alone has fungicidal activity in vitro by elevating intracellular calcium and reactive oxygen species(ROS).It was further demonstrated by histopathological study that BEA synergizes with a sub-therapeutic dose of ketoconazole(KTC)and could cure the murine model of disseminated candidiasis.Toxicity evaluation of BEA,including acute toxicity test,Ames test,and hERG(human ether-a-go-go-related gene)test promised that BEA can be harnessed for treatment of candidiasis,especially the candidiasis caused by ABC overexpressed multi-drug resistant C.albicans.Yaojun Tong Mei Liu Yu Zhang Xueting Liu Ren Huang Fuhang Song Huanqin Dai Biao Ren Nuo Sun Gang Pei Jiang Bian Xin-Ming Jia Guanghua Huang Xuyu Zhou Shaojie Li Buchang Zhang Takashi Fukuda Hiroshi Tomoda SatoshiOmura Richard DCannon Richard Calderone Lixin Zhang 2016Synthetic and Systems Biotechnology2016,1,3:1
14Dexmedetomidine administration before ,but not after ,ischemia attenuates intestinal injury induced by intestinal ischemia-reperfusion in rats 显示文摘Zhang Xuyu Liu Zimeng Wen Shihong 2012Anesthesiology2012,116,5:1
15The study of sea ice classification by radar observation显示文摘In order to mornitor the floating sea ice along the northeast coast of the Liaodong Gulf, since the winter of 1986, the Sea Ice Research Division of the Institute of Marine Enironmental Protection, State Oceanic Administration, has been making tests on the classification of sea ice in the Liaodong Gulf with radar at the Ice-survey Station at Bayuquan (Fig. 1 ).Sun Yanwei, Dong Xuyu, Zhang Likun and Xu YouliangInstitute of Marine Environmental Protection, State Oceanic Administration,PO Box 303, Dalian, 116023, ChinaGu ZhixianBeijing Institute of Environmental features, Ministry of Aero-space Industry, Beijing, China 1991Acta Oceanologica Sinica1991,10,2:0
16Unraveling the role of phase engineering in tuning photocatalytic hydrogen evolution activity and stability显示文摘In this work,taking NiSe_(2)as a prototype to be used as cocatalyst in photocatalytic hydrogen evolution,we demonstrate that the crystal phase of NiSe_(2)plays a vital role in determining the catalytic stability,rather than activity.Theoretical and experimental results indicate that the phase structure shows negligible influence to the charge transport and hydrogen adsorption capacity.When integrating with carbon nitride(CN)photocatalyst forming hybrids(m-NiSe_(2)/CN and p-NiSe_(2)/CN),the hybrids show comparable photocatalytic hydrogen evolution rates(3.26μmol/h and 3.75μmol/h).Unlike the comparable catalytic activity,we found that phase-engineered NiSe_(2)exhibits distinct stability,i.e.,m-NiSe_(2)can evolve H_(2) steadily,but p-NiSe_(2)shows a significant decrease in catalytic process(∼57.1%decrease in 25 h).The factor leading to different catalytic stability can be ascribed to the different surface conversion behavior during photocatalytic process,i.e.,chemical structure of m-NiSe_(2)can be well preserved in catalytic process,but partial p-NiSe_(2)tends to be converted to NiOOH.Jianjian Yi Zhou Zhou Yu Xia Ganghua Zhou Guoxiang Zhang Li Li Xuyu Wang Xingwang Zhu Xiaozhi Wang Huan Pang 2023Chinese Chemical Letters2023,34,11:0
17Image Recognition of Citrus Diseases Based on Deep Learning显示文摘In recent years,with the development of machine learning and deep learning,it is possible to identify and even control crop diseases by using electronic devices instead of manual observation.In this paper,an image recognition method of citrus diseases based on deep learning is proposed.We built a citrus image dataset including six common citrus diseases.The deep learning network is used to train and learn these images,which can effectively identify and classify crop diseases.In the experiment,we use MobileNetV2 model as the primary network and compare it with other network models in the aspect of speed,model size,accuracy.Results show that our method reduces the prediction time consumption and model size while keeping a good classification accuracy.Finally,we discuss the significance of using MobileNetV2 to identify and classify agricultural diseases in mobile terminal,and put forward relevant suggestions.Zongshuai Liu Xuyu Xiang Jiaohua Qin Yun Tan Qin Zhang Neal N.Xiong 2021Computers, Materials & Continua2021,,1:0
18Metasurface for oscillatory spin splitting along the optical path显示文摘Spin splitting of light originates from the interplay between the polarization and spatial degrees of freedom as a fundamental constituent of the emerging spin photonics,providing a prominent pathway for manipulating photon spin and developing exceptional photonic devices.However,previously relevant devices were mainly designed for routing monotonous spin splitting of light.Here,we realize an oscillatory spin splitting of light via metasurface with two channel Pancharatnam–Berry phases.For the incidence of a linearly polarized light,the concomitant phases arising from opposite spin states transition within pathways of the metasurface induce lateral spin splitting of light with alternately changed transport direction during beam guiding.We demonstrate the invariance of this phenomenon with an analogous gauge transformation.This work provides a new insight on steering the photon spin and is expected to explore a novel guiding mechanism of relativistic spinning particles,as well as applications of optical trapping and chirality sorting.YU LI XINHAO FAN XUYUE GUO YI ZHANG SHENG LIU BINGYAN WEI DANDAN WEN PENG LI JIANLIN ZHAO 2022Photonics Research2022,10,9:0
19Role of Anthropogenic Climate Change in Autumn Drought Trend over China from 1961 to 2014显示文摘Understanding the impact of anthropogenic climate change on drought is of great significance to the prevention of its adverse effects.Two drought indices,standardized precipitation index(SPI)and standardized precipitation evapotranspiration index(SPEI),are used here for the detection and attribution of autumn droughts in China,and for the exploration of the role played by the anthropogenic climate change.SPI is only related to precipitation,but SPEI involves both precipitation and potential evapotranspiration.For their trend’s spatial patterns,the historical simulations(including all forcings,noted as ALL)from 11 models of the Coupled Model Intercomparison Project phase 6,as an ensemble,are able to reproduce their observational counterpart.SPI shows wetting trend in the north of 35°N and drying trend in the south.SPEI shows drying trend in almost whole China.The drying trend in historical simulations ALL is significantly stronger,compared with the counterpart from the accompanying simulations(called NAT)with only natural forcings implemented.This result clearly indicates that anthropogenic climate change plays a dominant role in the enhancement of autumn drought in China.A more rigorous detection work is also performed with the signal’s fingerprint of ALL(and NAT)projected onto the observation and assessed with the background noise from no external-forcing control simulations.The trend pattern signal in ALL is significantly detected in observation for both SPI and SPEI,with a more pronounced signal in SPEI than in SPI,while the signal of NAT is not detected for neither SPI nor SPEI.Finally,extreme droughts(with indices beyond-2)are assessed in terms of probability ratio between ALL and NAT.It is shown that the anthropogenic precipitation change plays a leading role in the south of 35°N,while the anthropogenic temperature change leads in the north.Xuyu ZHANG Jinhua YU Laurent ZXLI Wei LI 2022Journal of Meteorological Research2022,36,2:0
20Application of eDNA Metabarcoding for Detecting Anura in North China显示文摘eDNA metabarcoding is an advanced method formonitoring biodiversityproposed in recent years.By analyzing DNA in water,soil and sediment samples,the technology obtains species distribution and population quantity information.It was found that macrobarcode technology is more accurate than the traditional method in measuring the species richness of some groups.In Europe,America and South America,the relia bility of this technology in monitoring amphibian diversity in the wild was studied,and it was found to be better than traditional biodiversity monitoring methods in detecting species diversity.At present,amphibian monitoring mainly depends on various traditional methods,such as transects,drift fence traps,artificial shelters and mark-recapture.These monitoring techniques have many shortcomings,such as low accuracy and strong subjectivity of study results.These technologies have poor effects on rare,invasive and endangered species with strong concealment ability,low density and strong seasonality and are difficult to implement in sites inaccessible to people.Traditional monitoring technology also requires considerable investment of human and material resources,and the economic cost is relatively high,while eDNA metabarcoding ismore efficient and less costly,so it is important to use eDNA meta barcoding in amphibian monitoring in China.In this study,the eDNA meta barcoding and traditional line transect method(TLTM)were used to study the characteristics of the two methods in the Beijing-Tianjin-Hebeiregion.Repeated samplingwas conducted on 58 waterbodies in July 2019 and June 2020.After sequencing the samples using highthroughput sequencing technology,the differences between metabarcoding and commonly used TLTM surveys in detecting the diversity of four amphibians in North China were assessed.Our results showed that eDNA meta barcoding is more sensitive to the detection of the four amphibian species in the sampling area,and the combined use of eDNA metabarcoding and TLTM can improve the survey results of amphibians in the survey area to the greatest extent.In addition,in the process of species classification and identification of metabarcoding results,7 species of reptiles were detected,indicating that eDNA metabarcoding is also useful to detect reptiles.The results of this study indicate that metabarcoding in combination with TLTM can accurately estimate the diversityof amphibians in a short-term survey in North China and is also useful in reptile species detection.Wenhao LI Mingshuo QIN Xianglei HOU Jiaqi ZHANG Siqi WANG Yu LI Zexu LUO Teng DENG Tianjian SONG Chunxia XU Xuan LIU Xuyu WANG Yiming LI 2022Asian Herpetological Research2022,13,4:0
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