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Journal of Arid Land 2017年第1期9卷 153-159页

作者： yuan Lei qi Aladaer CHENG Yun SAGEN Guli QU yuan LIU Bin Xinjiang Lop Nor Wild Camel National Nature Reserve Urumqi 830011 China Animal Science Department Xinjiang Agricultural University Urumqi 830052 China Key Laboratory of Biogeography and Bioresources in Arid Land Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China The People's Hospital of Xinjiang Uygur Autonomous Region Urumqi 830001 China

This study aimed to reveal the microbial diversity in the fecal samples of bactrian camels using the 16 S r RNA sequencing analysis on the Illumina mi Seq platform. Three fecal samples were collected from two geographical regions in China. Operational taxonomic unit（OTU） clustering was performed by identifying an OTU at 97% sequence identity. The alpha and beta diversities were applied to estimate the differences in microbial diversity among the three fecal samples. Totally, 4409, 3151 and 4075 OTUs in the fecal samples were identified in the Lop Nor wild camel（Camelus ferus）, the domestic camel（C. bactrianus） and Dunhuang wild camel（C. ferus）, respectively. The majority of bactreria were affiliated with phylum Firmicutes and Bacteroidetes in the three samples. The wild camels had higher gastrointestinal tract microbial diversity than the domestic one, while the microbial composition of the Lop Nor wild camel shared higher similarity with domestic camel at the genus and family levels than that of the Dunhuang wild camel did. Our results may provide a theoretical basis for assessing their health conditions and may thus be useful for protecting the critically endangered species of C. ferus.

关键词： bactrian camels Camelus ferus fecal microbiota 16S rRNA high-throughput sequencing

Fabrication and evaluation of a BMP-2/dexamethasone co-loaded gelatin sponge scaffold for rapid bone regeneration

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Regenerative Biomaterials 2022年第1期9卷 303-313页

作者： qi Gan Hao Pan Wenjing Zhang yuan yuan Jiangchao qian Changsheng Liu Key Laboratory for Ultrafine Materials of ministry of Education East China University of Science and TechnologyShanghai 200237PR China The State Key Laboratory of Bioreactor Engineering East China University of Science and TechnologyShanghai 200237PR China Engineering Research Center for Biomedical Materials of the ministry of Education East China University of Science and TechnologyShanghai 200237PR China Frontiers Science Center for Materiobiology and Dynamic Chemistry East China University of Science and TechnologyShanghai 200237PR China

Improving the osteogenic activity of BMP-2 in vivo has significant clinical application *** this research,we use a clinical gelatin sponge scaffold loaded with BMP-2 and dexamethasone(Dex)to evaluate the osteogenic activity of dual drugs via ectopic osteogenesis in *** also investigate the mechanism of osteogenesis induced by BMP-2 and Dex with C2C12,a multipotent muscle-derived progenitor *** results show that the gelatin scaffold with Dex and BMP-2 can significantly accelerate osteogenesis in *** is indicated that compared with the BMP-2 or Dex alone,100nM of Dex can dramatically enhance the BMP-2-induced alkaline phosphatase activity(ALP),ALP mRNA expression and *** studies show that 100nM of Dex can maintain the secondary structure of BMP-2 and facilitate recognition of BMP-2 with its receptors on the surface of C2C12 *** also find that in C2C12,Dex has no obvious effect on the BMP-2-induced Smad1/5/8 protein expression and the STAT3-dependent pathway,but Runx2-dependent pathway is involved in the Dex-stimulated osteoblast differentiation of BMP-2 both in vitro and in *** on these results,a potential mechanism model about the synergistic osteoinductive effect of Dex and BMP-2 in C2C12 cells via Runx2 activation is *** may provide a theoretical basis for the pre-clinical application of Dex and BMP-2 for bone regeneration.

关键词： BMP-2 dexamethasone Runx2 pre-clinical bone regeneration

Star formation properties of galaxy cluster A1767

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Research in Astronomy and Astrophysics 2015年第11期15卷 1773-1783页

作者： Peng-Fei Yan Feng Li qi-Rong yuan Department of Physics Nanjing Normal University School of Mathematics and Physics Qingdao University of Science and Technology School of Mathematics and Physics Changzhou University

Abell 1767 is a dynamically relaxed, c D cluster of galaxies with a redshift of 0.0703. Among 250 spectroscopically confirmed member galaxies within a projected radius of 2.5r200, 243 galaxies（ Digital Sky Survey. Based on this ～97%） are spectroscopically covered by the Sloanhomogeneous spectral sample, the stellar evolutionary synthesis code STARLIGHT is applied to investigate the stellar populations and star formation histories of galaxies in this cluster. The star formation properties of galaxies, such as mean stellar ages, metallicities, stellar masses, and star formation rates, are presented as functions of local galaxy density. A strong environmental effect is found such that massive galaxies in the high-density core region of the cluster tend to have higher metallicities, older mean stellar ages, and lower specific star formation rates（SSFRs）, and their recent star formation activities have been remarkably suppressed. In addition, the correlations of the metallicity and SSFR with stellar mass are confirmed.

关键词： galaxy galaxies stellar luminosity galactic SDSS dynamically nearby stars older

An on-line solid phase extraction-liquid chromatography tandem mass spectrometry method for the determination of perfluoroalkyl substances in the Antarctic ice core samples

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Chinese Chemical Letters 2015年第9期26卷 1073-1078页

作者： Ya-Li Shi yuan-yuan Pan Li-Na Liang Ya-qi Cai State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental ScienceChinese Academy of Sciences Thermo Fisher Scientific(China)Co. Ltd.

An on-line solid phase extraction-high performance liquid chromatography-tandem mass spectrometry method for the analysis of perfluoroalkyl substances（PFASs） in water samples was *** optimal analytical conditions were obtained through the optimization of the extraction efficiency of online solid phase extraction column,sample loading rate and loading volume,and the concentration of ammonium acetate in mobile *** the optimal condition,the analytical method displayed good linearity（r^2〉0.99） for 12 PFASs（C5-C14 perfluoroalkyl carboxylic acids and C6/C8 perfluoroalkyl sulfonic acids） over a concentration range of 0.5-100 ng/*** limits of quantitation for samples were between 0.025 ng/L and 0.5 ng/L and the relative standard deviations（RSD） of five consecutive analyses were less than 10%for 1 ng/L standard *** results were obtained using this analytical method for the analysis of perfluoroalkyl substances in Antarctic ice core *** recoveries of all perfluoroalkyl substances were in a range of 73%-117%when the samples were spiked with standards at the concentrations of 2.5 ng/L and 25 ng/L.

关键词： Perfluoroalkyl substances On-line solid phase extraction LC-MS/MS Antarctic ice cores

3D metal-organic frameworks based on lanthanide-seamed dimeric pyrogallol[4]arene nanocapsules

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Science China Chemistry 2018年第6期61卷 664-669页

作者： Kongzhao Su mingyan Wu Wenjing Wang mi Zhou Daqiang yuan Maochun Hong State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou 350002 China University of the Chinese Academy of Sciences Beijing 100049 China

Two novel 3D metal-organic frameworks(MOFs)with cds network,{[Me NH_3]_7[Ln_8(Pg C_2)_2(H_2O)_y(HCOO)_7]}_n·x(Solvent)(FJI-Y4,FJI=Fujian Institute,Ln=Gd,y=12;FJI-Y5,Ln=Dy,y=11;Pg C_2=C-ethylpyrogallol[4]arene),based on unprecedented dimeric pyrogallol[4]arene-based Ln_8metal-organic nanocapsule(MONC)supramolecular building blocks and formate linkers,have been prepared under solvothermal *** our best of knowledge,they present not only the first two examples of 3D hierarchical structures constructed from MONCs in metal-pyrogallol[4]arene system,but also the first two examples of MOFs based on lanthanide ***,the inner cavity volume of the Ln_8capsule in FJI-Y4 and FJI-Y5 is approximately151?~3,which is larger than those found in previous transition metal-seamed dimeric Pg C_n-based *** investigation on FJI-Y4 suggests a significant magnetocaloric effect(23.97 J kg^(-1)K^(-1),ΔH=7 T,2.5 K),while FJI-Y5 exhibits slow relaxation of the magnetization.

关键词： lanthanide pyrogallolarene metal-organic frameworks(MOFs) magnetic propeties

Simple method to rapidly fabricate chain-like carbon nanotube films and its field emission properties

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International Journal of minerals,Metallurgy and Materials 2010年第3期17卷 371-375页

作者： Zhi-yuan Wu Shuang-qi Hu Zhi-qian Wang Chemical Industry and Ecology Institute North University of China Taiyuan 030051 China

A simple process to fabricate chain-like carbon nanotube （CNT） films by microwave plasma-enhanced chemical vapor deposition （MPCVD） was developed successfully. Prior to deposition, the Ti/Al2O3 substrates were ground with Fe-doped SiO2 powder. The nano-structure of the deposited films was analyzed by scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, and Raman spectroscopy. The field electron emission characteristics of the chain-like carbon nanotube films were measured under the vacuum of 10-5 Pa. The low turn-on field of 0.80 V/μm and the emission current density of 8.5 mA/cm2 at the electric field of 3.0 V/μm are obtained. Based on the above results, chain-like carbon nanotube films probably have important applications in cold cathode materials and electrode materials.

关键词： carbon nanotube (CNT) chain-like film microwave plasma-enhanced chemical vapor deposition (MPCVD) field emission

Readout system for ground-based tests of BGO calorimeter of DAMPE satellite

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Nuclear Science and Techniques 2017年第10期28卷 45-50页

作者： Jun-Bin Zhang Chang-qing Feng Si-yuan Ma qi Wang Shu-Bin Liu qi An State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science andTechnology of ChinaHefei 230026China

A readout system for ground-based tests of the bismuth germanium oxide(BGO) calorimeter of the Dark Matter Particle Explorer satellite is described in this *** system mainly consists of a data acquisition board with a field-programmable gate array to implement the control logic, and a graphical user interface software based on LabWindows/CVI. The system has been successfully applied in a series of ground-based environmental experiments and almost all the performance tests throughout the entire manufacturing processes. These contribute significantly to the development of the BGO calorimeter before being submitted for satellite-level integration.

关键词：卫星地面测试读出系统 BGO LabWindows/CVI 现场可编程门阵列阻尼图形用户界面暗物质粒子

Tunable electronic structure and magnetic coupling in strained two-dimensional semiconductor MnPSe3

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Frontiers of physics 2018年第4期13卷 167-174页

作者： qi Pei Xiao-Cha Wang Ji-Jun ZOU Wen-Bo mi Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology School of Science Tianjin University Tianjin 300354 China School of Electrical and Electronic Engineering Tianjin University of Technology Tianjin 300384 China Key Laboratory for Green Chemical Technology of the ministry of Education School of Chemical Engineering and Technology Tianjin University Tianjin 300354 China

The electronic structures and magnetic properties of strained monolayer MnPSe3 are investigated sys- tematically via first-principles calculations. It is found that the magnetic ground state of monolayer MnPSe3 can be significantly affected by biaxial strain engineering, while the semiconducting char- acteristics are well-preserved. Owing to the sensitivity of the magnetic coupling towards structural deformation, a biaxial tensile strain of approximately 13% can lead to an antiferromagnetic （AFM）- ferromagnetic （FM） transition. The strain-dependent magnetic stability is mainly attributed to the competition of the direct AFM interaction and indirect FM superexchange interaction between the two nearest-neighbor Mn atoms. In addition, we find that FM MnPSe3 is an intrinsic half semiconductor with large spin exchange splitting in the conduction bands, which is crucial for the spin-polarized carrier injection and detection. The sensitive interdependence among the external stimuli, electronic structure, and magnetic coupling makes monolayer MnPSe3 a promising candidate for spintronics.

关键词： two-dimensional semiconductor MnPSe3 strain engineering electronic structure magnetic coupling

Surface-state controlled synthesis of hydrophobic and hydrophilic carbon dots

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Nano Research 2024年第5期17卷 4391-4399页

作者： Chan Wang yuan Fang mi Zhang Huan Zhuo qijun Song Han Zhu Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China Jiangsu Snow Leopard Household Chemical Co. Ltd.Wuxi 214400China

It is of great significance to synthesize carbon dots(CDs)with desirable hydrophilicity for the ever-growing application of CDs in different *** this study,the hydrophilic and hydrophobic CDs were facilely prepared by solvothermal treatment of o-dihydroxybenzene and urea in N,N-dimethylformamide(DMF).Optimization experiments revealed that the solvothermal temperature has a great impact on the surface states of the *** hydrophobic CDs with a contact angle of 110.7°was obtained at 200℃.The structural and optical characterizations,along with theoretical calculations elucidated that the lipophilic nature of the CDs was resulting from the formation of polymer *** presence of extended conjugated sp^(2)-domains and amino groups contributed to the red emission of the CDs synthesized at low reaction temperatures(160-200℃).With the further increase of solvothermal temperature,the hydrophobic CDs were gradually transformed to the hydrophilic state accompanying the blue shift of the fluorescence of the *** highly hydrophilic CDs with a contact angle of 25.9°were obtained at 240℃ due to the increased formation of hydrophilic functional groups on the surface of *** red emissive CDs exhibited a sensitive color and fluorescence response to ethanol content while the fluorescence of the blue emissive CDs remained *** combining the two kinds of CDs,a dual-emission sensor was constructed,which was successfully applied for the evaluation of the alcoholic strength in commercial Baijiu commodities in both fluorometric and colorimetric modes.

关键词： carbon dots surface chemistry hydrophilicity and hydrophobicity solvothermal temperature alcoholic strength evaluation

Burning products of TA15 titanium alloy by friction oxygen concentration method

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Rare Metals 2018年第11期37卷 952-960页

作者： Nan Sui Guang-Bao mi Meng-qi Yan Jing-Xia Cao Xu Huang Aviation Key Laboratory of Science and Technology on Advanced Titanium Alloys AECC Beijing Institute of Aeronautical Materials

The microstructural characteristics, elemental distribution law and microscopic formation mechanism of the burning products of TA15 titanium alloy were investigated by friction oxygen concentration method, associated with in situ observation, X-ray diffraction(XRD),scanning electron microscopy(SEM) and energy-dispersive spectroscopy(EDS) analyses, providing the thoughts to improve fireproof property. The results show that, when the friction contact pressure(p) is 0.20 MPa and oxygen concentration of premixed air flow(c) is 60 vol%, TA15 titanium alloy produces violent sparks and presents dazzling white light during combustion. The generated products after burning are mainly TiOand small amount of AlOoxides. Four distinct zones form from the combustion surface to the alloy matrix, and they are in the sequence of combustion zone, fusion zone, heat-affected zone and transition zone. Further, combustion zone is composed of TiOand A1203 compounds, containing obvious cracks. In the fusion zone, discontinuous oxygenrich Al-based solid solution forms, and the elemental distribution has strong volatility. In the heat-affected zone,there are abundant of Ti-based solid solution and small amount of Al-and Mo-based solid solution. Transition zone is made of lamellar structure. Two technical approaches are given to prevent oxygen diffusion inside the reaction zone and reaction-affected zone. On the one hand,the content of Al is designed as the upper limit of alloy composition; on the other hand, fireproof coatings are deposited on the surface of the alloy.

关键词： Friction oxygen concentration method TA15 titanium alloy Burning products microstructure Titanium fire