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Journal of Arid Land 2016年第1期8卷 60-76页

作者： wang yamin FENG Qi KANG Xingcheng Alxa Desert Eco-hydrology Experimental Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences University of Chinese Academy of Sciences

Long-term temperature variability has significant effects on runoff into the upper reaches of inland rivers. This paper developed a tree-ring chronology of Qilian juniper (Sabina przewalskii Kom.) from the upper tree-line of the middle Qilian Mountains within the upper reaches of Heihe River Basin, Northwest China for a long-term reconstruction of temperature at the study site. In this paper, tree-ring chronology was used to examine climate-growth associations considering local climate data obtained from Qilian Meteorological Station. The results showed that temperatures correlated extremely well with standardized growth indices of trees (r=0.564, Pth century. Colder events and intervals coincided with wet or moist conditions in and near the study region. The reconstructed temperature agreed well with other temperature series reconstructed across the surrounding areas, demonstrating that this reconstructed temperature could be used to evaluate regional clima

关键词： tree-ring climatic response temperature reconstruction upper reaches of Heihe River Basin

Orbital reference frame estimation with power spectral density constraints for drag-free satellites

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Chinese Journal of Aeronautics 2016年第6期29卷 1721-1729页

作者： Zhang Yonghe wang yamin Mao Qingyun Liang Xuwen Shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai 200050China Shanghai Engineering Centre for Microsatellites Shanghai 201210China Joint Key Laboratory of Microsatellite Chinese Academy of SciencesShanghai 201210China

The drag-free satellites are widely used in the field of fundamental science as they enable the high-precision measurement in pure gravity fields. This paper investigates the estimation of local orbital reference frame(LORF) for drag-free satellites. An approach, taking account of the combination of the minimum estimation error and power spectral density(PSD) constraint in frequency domain, is proposed. Firstly, the relationship between eigenvalues of estimator and transfer function is built to analyze the suppression and amplification effect on input signals and obtain the eigenvalue range. Secondly, an optimization model for state estimator design with minimum estimation error in time domain and PSD constraint in frequency domain is established. It is solved by the sequential quadratic programming(SQP) algorithm. Finally, the orbital reference frame estimation of low-earth-orbit satellite is taken as an example, and the estimator of minimum variance with PSD constraint is designed and analyzed using the method proposed in this paper.

关键词： Drag-free satellite Orbital reference frame Power spectral density State estimation Transfer function

Concept of the Solar Ring mission: Preliminary design and mission profile

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Science China(Technological Sciences) 2021年第1期64卷 131-138页

作者： wang yamin CHEN Xin wang PengCheng QIU ChengBo wang YuMing ZHANG YongHe Innovation Academy for Microsatellites Chinese Academy of Sciences(CAS)Shanghai 201203China Key Lab of Microsatellite Chinese Academy of SciencesShanghai 201203China Shanghai Engineering Center for Microsatellites Shanghai 201203China CAS Key Laboratory of Geospace Environment School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology University of Science and Technology of ChinaHefei 230026China

The Solar Ring mission, a concept to monitor the Sun and inner heliosphere from multiple perspectives, has been funded for prephase study by the Strategic Priority Program of Chinese Academy of Sciences in space sciences. The Solar Ring is comprised of 6 spacecraft, grouped in three pairs, moving around the Sun in an elliptical orbit in the ecliptic plane. The mission costs,including launch fee, deep-space maneuvers, and deployment time of the ring, are highly relevant to the working orbit, deepspace transfer, and phase angle within a group. The preliminary mission profile is analyzed and designed in this paper. The launch way, two spacecraft with one rocket, is adopted. The deployment time, phasing maneuvers, and C_(3) of launch energy are evaluated for the elliptical orbits with the perihelion between 0.7 and 0.9 AU using the rockets of Long March(LM) 3A and *** simulations show two candidate trajectories: fast deployment within 4 years by LM-3B, medium deployment more than 6 years by cheaper rocket of LM-3A. In order to obtain both fast deployment and low launch cost, another orbit profile is proposed by shortening the phase angle within a group. The suggested working orbits and the corresponding costs of launch,deployment time, and phasing maneuvers will strongly support the science objectives.

关键词： solar and heliospheric observations deep-space transfer orbit optimization

A short note on the horizontal and vertical movements of a whale shark, Rhincodon typus, tracked by satellite telemetry in the South China Sea

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Integrative Zoology 2012年第1期7卷 94-98页

作者： yamin wang Wei LI Xiaoguang ZENG Yunchen CUI College of Ocean Shandong University at WeihaiWeihaiChina Chinese University of Hong Kong Hong KongChina Ministry of Agriculture Bureau of the South China Sea FisheriesGuangzhouChina

Whale sharks,a global migratory species,are often reported entangled in fishing nets in coastal areas of *** effectiveness of conservation measures has been constrained by very limited knowledge on their move-ments and preferred habitats in the coastal areas of *** the first time,we tracked the movements of 2 whale sharks by satellite telemetry in China' *** tracking results of 1 whale shark revealed that it travelled in the South China Sea in a south-eastern direction,parallel to the eastern coast of *** dis-tance travelled was 1018 km,in approximately 74 days,with a mean speed of 14 km per *** appeared to head towards the cool upwelling zones in southern Vietnam at the time of the tag’s *** our study,it was observed that this whale shark was a surface dweller and spent approximately 45%of its time above 10 m water depth and 90%of its time above 50 m *** also tended to stay in water temperatures between 27 and 30°C,and was rarely recorded in water below 20°*** preliminary study indicates the importance of shal-low waters as the foraging habitat for whale sharks,and has implications for their management and conserva-tion.

关键词： pop-up archival tag South China Sea whale shark

A thermo-responsive rewritable plasmonic bio-memory by regulating single core-satellite gold nanocluster dissociation

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Nano Research 2024年第8期17卷 7275-7282页

作者： Wen Zhang Yi wang yamin wang Xiaomei Lu Weibing Wu Quli Fan Lei Zhang State Key Laboratory of Organic Electronics and Information Displays&Institute of Advanced Materials(IAM) Nanjing University of Posts&TelecommunicationsNanjing 210023China Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources College of Light Industry and Food EngineeringNanjing Forestry UniversityNanjing 210037China Zhengzhou Institute of Biomedical Engineering and Technology Zhengzhou 450001China Key Laboratory of Flexible Electronics(KLOFE) Institute of Advanced Materials(IAM)&School of Flexible Electronics(Future Technologies)Nanjing Tech University(Nanjing Tech)Nanjing 211816China

A thermo-responsive rewritable plasmonic bio-memory chip has been successfully fabricated on an indium tin oxide(ITO)glass slide by assembling core-satellite gold nanoclusters with different size of gold nanoparticles(AuNPs)using double-strand DNA(dsDNA)*** the prepared 70@DNA20@13 gold nanoclusters(AuNCs)exhibited more stable and greater photothermal conversion *** short time irradiation by 633 nm microbeam laser,every individual AuNCs could be excited and remove the satellite AuNPs on its ***,in the dissociation process of AuNCs with 3−5 satellite,its color would change from yellow to green,which showed more significant reduction in the red channel of the dark-field microscopy(DFM)images and could be defined to state“0”and“1”***,this plasmonic nano bio-memory could transform cyclically its state between 0 and 1 which exhibited excellent rewritable ability.

关键词： plasmonic assembly thermal-responsive single nanoparticle rewritable bio-memory

Facile Synthesis of Mesoporous Si-containing γ-Al2O3 Nanofiber with Enhanced Thermal Stability

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Chemical Research in Chinese Universities 2015年第1期31卷 156-159页

作者： HU Fang wang yamin LAI Xiaoyong WU Yusheng DU Fei wang Chunzhong School of Materials Science and Engineering Shenyang University of Technology Shenyang 110870 P. R. China State Key Laboratory Cultivation Base of Natural Gas Conversion Ningxia University Yinchuan 750021 P. R. China Key Laboratory of Advanced Batteries Physics and Technology Ministry of Education College of Physics Jilin University Changchun 130012 P. R. China

Mesoporous γ-Al2O3 nanofiber was prepared via a simple reverse precipitation route using Si-containing Al（OH）3 and HNO3 as raw materials. The resultant Si-containing mesoporous γ-Al2O3 nanofiber exhibited high surface area of 320 m^2/g, large pore volume of 1.17 cm^3/g and large pore size of 10.5 nm. The introduction of Si element remarkably enhanced the thermal stability of mesoporous γ-Al2O3. The as-prepared nanofiber could maintain relative high surface area（110 m^2/g） and pore volume（0.73 cm^3/g） up to 1100 ℃. The effects of various experimental conditions, such as pH value, reaction temperature and aging temperature on the structural properties of the mesoporous γ-Al2O3 were also investigated.

关键词： Mesoporous γ-Al2O3 Reverse precipitation Thermal stability Nanofiber

Vegetation cover change and the driving factors over northwest China

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Journal of Arid Land 2011年第1期3卷 25-33页

作者： ShengPei DAI Bo ZHANG HaiJun wang yamin wang LingXia GUO XingMei wang Dan LI The College of Geography and Environmental Science Northwest Normal University Lanzhou 730070 China The Engineering and Technical College of Chengdu University of Technology Leshan 614007 China

In this paper the spatio-temporal variation of vegetation cover in northwest China during the period of 1982-2006 and its driving factors were analyzed using GIMMS/NDVI data. The annual average NDVI was increased with a rate of 0.0005/a in northwest China and there was an obvious difference between regions. The trend line slopes of NDVI were higher than 0.0005 in the Tianshan Moutains and Altay Mountains of Xinjiang, the Qilian Mountains of Gansu and the eastern part of Qinghai, which indicated the vegetation cover was significantly increased in these areas. The trend line slopes of NDVI were lower than -0.0005 in the southern region of Qinghai, the border regions of Shaanxi and Ningxia, the parts of Gansu and Tarim Basin, Turpan and Tuoli in Xinjiang, which indicated the vegetation cover was declined in these areas. The NDVI of woodland, grassland and cultivated land had an ascending tendency during the study period. The study shows that the vegetation cover change was caused by both natural factors and human activities in northwest China. The natural vegetation change, such as forests was influenced by climate change, while human activities were the main reason to the change of planting vegetation. The changes of vegetation covers for different elevations, slopes and slope aspects were quite different. When the eleva- tion is exceeded to 4,000 m, the NDVI increasing trend was very low; the NDVI at the slope of less than 25~ was increased by the ecological construction; the variation of NDVI on sunny slope was stronger than that on shady slope. The temperature rose significantly in recent 25 years in northwest China by an average rate of 0.67^-C/10a, and precipitation increased by an average rate of 8.15 mm/10a after 1986. There was positive correlation between vegetation cover and temperature and annual precipitation changes. Rising temperature increased the evaporation and drought of soils, which is not conducive to plant growth, and the irrigation in agricultura

关键词： NDVl vegetation cover climate change human activity northwest China

Discovery of natural products capable of inducing porcine host defense peptide gene expression using cell-based high throughput screening

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Journal of Animal Science and Biotechnology 2021年第2期12卷 598-610页

作者： Jing wang Wentao Lyu Wei Zhang Yonghong Chen Fang Luo yamin wang Haifeng Ji Guolong Zhang Institute of Animal Husbandry and Veterinary Medicine Beijing Academy of Agriculture and Forestry SciencesBeijingChina Sino-US Joint Laboratory of Animal Science Beijing Academy of Agriculture and Forestry SciencesBeijingChina Institute of Quality and Standard for Agro-products Zhejiang Academy of Agricultural SciencesHangzhouChina College of Agriculture Ningxia UniversityYinchuanChina Department of Animal and Food Sciences Oklahoma State UniversityStillwaterOKUSA

Background:In-feed antibiotics are being phased out in livestock production *** to antibiotics are urgently needed to maintain animal health and production *** defense peptides(HDPs)are known for their broad-spectrum antimicrobial and immunomodulatory *** the synthesis of endogenous HDPs represents a promising antibiotic alternative strategy to disease control and ***:To identify natural products with an ability to stimulate the synthesis of endogenous HDPs,we performed a high-throughput screening of 1261 natural products using a newly-established stable luciferase reporter cell line known as IPEC-J2/*** ability of the hit compounds to induce HDP genes in porcine IPEC-J2 intestinal epithelial cells,3D4/31 macrophages,and jejunal explants were verified using *** of the antibacterial activity of porcine 3D4/31 macrophages against a Gram-negative bacterium(enterotoxigenic ***)and a Gram-positive bacterium(Staphylococcus aureus)were further confirmed with four selected HDP-inducing ***:A total of 48 natural products with a minimum Z-score of 2.0 were identified after high-throughput screening,with 21 compounds giving at least 2-fold increase in luciferase activity in a follow-up dose-response *** and deoxyshikonin were further found to be the most potent in inducing pBD3 mRNA expression,showing a minimum 10-fold increase in IPEC-J2,3D4/31 cells,and jejunal *** compounds such as isorhapontigenin and calycosin also enhanced pBD3 mRNA expression by at least 10-fold in both IPEC-J2 cells and jejunal explants,but not 3D4/31 *** addition to pBD3,other porcine HDP genes such as pBD2,PG1-5,and pEP2C were induced to different magnitudes by xanthohumol,deoxyshikonin,isorhapontigenin,and calycosin,although clear gene-and cell type-specific patterns of regulation were ***,these four compounds had a minimum effect on the expre

关键词： Antibiotic alternatives High throughput screening HDP inducers Host defense peptides Natural products

The high catalytic activity and strong stability of 3%Fe/AC catalysts for catalytic wet peroxide oxidation of m-cresol: The role of surface functional groups and FeO_(x) particles

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Chinese Journal of Chemical Engineering 2022年第4期35卷 105-114页

作者： Peiwei Han Chunhua Xu yamin wang Chenglin Sun Huangzhao Wei Haibo Jin Ying Zhao Lei Ma Beijing Key Laboratory of Fuels Cleaning and Advanced Catalytic Emission Reduction Technology/College of Chemical Engineering Beijing Institute of Petrochemical TechnologyBeijing 102617China Shandong Key Laboratory of Water Pollution Control and Resource Reuse School of Environmental Science and EngineeringShandong UniversityQingdao 266237China Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023China

FeO;supported on activated carbon(AC) has been shown to be an ideal catalyst for catalytic wet peroxide oxidation(CWPO) due to its high CWPO reaction activity and stability. Although there have been some studies on the mechanism of Fe/AC catalysis in CWPO, the specific contribution of each component(surface oxygen groups and FeOxon AC) inside an Fe/AC catalyst and their corresponding reaction mechanism remain unclear, and the reaction stability of CWPO catalysts has rarely been discussed. Then the optimal CWPO catalyst in our laboratory, 3%Fe/AC, was selected.(1) By removing certain components on the AC through heat treatment, its contribution to the reaction and the corresponding reaction mechanism were investigated. With the aid of temperature-programmed desorption–mass spectrometry(TPD–MS) and the CWPO reaction, the normalized catalytic contributions of components were shown to be: 37.3%(carboxylic groups), 5.3%(anhydride), 19.3%(ether/hydroxyl),-71.4%(carbonyl groups) and 100%(FeOx),respectively. DFT calculation and EPR analysis confirmed that carboxylic groups and Fe_(2)O_(3) are able to activate the H_(2)O_(2) to generate·OH.(2) The catalysts at were characterized at different reaction times(0 h, 450 h, 900 h, 1350 h, and 1800 h) by TPD–MS and M?ssbauer spectroscopy. Results suggested that the number of carboxylic goups gradually increased and the size of paramagnetic Fe_(2)O_(3) particle crystallites gradually increased as the reactions progressed. The occurrence of strong interactions between metal oxides and AC was also confirmed. Due to these effects, the strong stability of 3%Fe/AC was further improved. Therefore, the reasons for the high activity and strong stability of 3%Fe/AC in CWPO were clearly shown. We believe that this work provides an idea of the removal of cresols from wastewater into the introduction to show the potential applications of CWPO.

关键词： Catalytic wet peroxide oxidation Fe/AC catalyst Surface functional groups Reaction mechanism

Opportunities search of transfer between interplanetary halo orbits in ephemeris model

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Science China(Technological Sciences) 2013年第1期56卷 188-193页

作者： wang yamin CUI PingYuan QIAO Dong Institute of Deep Space Exploration Beijing Institute of Technology Key Laboratory of Dynamics and Control of Flight Vehicle Ministry of Education

In this paper,a two-level search method for searching transfer opportunities between interplanetary halo orbits,exploiting the invariant manifolds of the restricted three-body problem,is *** the method,the first-level search procedure is performed under the conditions of the initial time of escape manifold trajectory of the Sun-Earth halo orbit and the terminal time of capture manifold of the target planet fixed,by solving the optimal two-impulsive heliocentric trajectory to connect the two manifold *** contour map,helpful to the understanding of the global characteristics of the transfer opportunities,taking the initial time of escape manifold and the terminal time of capture manifold as variables,the optimal velocity increment of the first-level search as objective function,is used for the second-level ***,taking the Earth-Mars and Earth-Venus halo to halo transfers for example,the transfer opportunities in 2015-2017 are *** results show the effectiveness of the proposed method and reveal the property of quasi-period of transfer opportunities between interplanetary halo orbits.

关键词： ephemeris model halo orbit invariant manifold transfer opportunities search

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