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Genesis of fahlore in the Tianbaoshan lead–zinc deposit, Sichuan Province, China: a scanning electron microscopy–energy dispersive spectroscopy study

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Acta Geochimica 2018年第6期37卷 842-853页

作者： Yusi hu Lin Ye zhenli Li zhilong huang Jiawei zhang State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang550081China University of Chinese Academy of Sciences Beijing100049China Guizhou Geological Survey Bureau of Geology and Mineral Exploration and Development of Guizhou ProvinceGuiyang550081China

The Tianbaoshan deposit, located in the southwestern part of the Yangtze Block, is a representative Pb–zn deposit in the Sichuan–Yunnan–Guizhou Pb–zn metallogenic province. The Pb–zn orebodies are hosted in the upper Sinian Dengying Formation dolostone. The predominant minerals are sphalerite, galena, pyrite, chalcopyrite, quartz, and calcite with minor arsenopyrite,fahlore, and dolomite. The deposit is characterized by relatively strong Cu mineralization. however, the relationship between Pb–zn and Cu mineralization is unknown. We analyzed the mineralogy and composition of fahlore, chalcopyrite, arsenopyrite, sphalerite, and galena using scanning electron microscopy–energy dispersive spectroscopy, with the aim of providing new evidence for the genesis of the Pb–zn–(Cu) ore. The results show that the Cu ore in the deposit is dominated by chalcopyrite and fahlore, both of which formed before or during the Pb–zn ore-forming stage. The fahlore showed dramatic compositional variation and was characterized by negative correlations between Ag and Cu, and between As and Sb,suggesting substitution of Ag for Cu, and that As and Sb substitute in the same site in the fahlore lattice. Based on backscattered electron images and composition, the fahlorewas divided into two types. Type I fahlore crystallized early and is characterized by enrichment of Cu and depletion in Ag and Sb. Type II fahlore formed after Type I, and is rich in Ag and poor in Cu and As. Moreover,galena and fahlore are the host minerals of Ag. The variation of valence state with As host mineral—from fahlore to arsenopyrite—indicates the metallogenic environment changed from relatively oxidizing to reducing with a high p h. In the light of Gibbs energies of reciprocal reactions and isotherms for cation exchange, the composition of the fahlore implies its ore-forming temperature was lower than220 °C, corresponding with typical Mississippi Valley-type(MVT) deposits. Based on the geologic character and geochemical

关键词： Fahlore Tianbaoshan Pb-zn deposit SEM- EDS-MVT deposit

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A Novel Chitosan-based Sponge Coated with Self-assembled Thrombin/Tannic Acid Multilayer Films as a hemostatic Dressing

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Chinese Journal of Polymer Science 2015年第2期33卷 284-290页

作者： Xiao-fei huang Jing-wei Jia 王征科胡巧玲 MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University

In order to prepare a novel hemostatic dressing for uncontrolled hemorrhage, a porous chitosan sponge was coated with self-assembled（thrombin/tannic acid）n films, which were based on hydrogen bonding interactions between thrombin and tannic acid at physiologic p h. According to the whole blood clotting test, the coated chitosan sponges showed a significantly high rate of blood clotting due to the addition of thrombin. On the other hand, the storable half-life of immobilized thrombin is extended to 66.9 days at room temperature, which is 8.5 times longer than unfixed thrombin. It is because of the immobilization effect of, not only the porous structure of chitosan sponge but also the interactions between thrombin and tannic acid. In addition, the tannic acid has similar antibacterial effect to chitosan. Therefore, it is an excellent combination of chitosan, thrombin and tannic acid. Besides, all of materials in this research have been approved by the United States Food and Drug Administration（FDA）. So the chitosan-based sponge is a promising candidate dressing for uncontrolled hemorrhage due to its storable, bio-safe and highly effective hemostatic properties.

关键词： Chitosan Thrombin Tannic acid Layer-by-Layer assembly hemostatic dressing

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In-situ polymerized nanosilica/acrylic/epoxy hybrid coating:Preparation,microstructure and properties

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Science China(Technological Sciences) 2009年第8期52卷 2204-2209页

作者： LU hongBin GU Minhao huang JianFeng hU Yong MENG XiangKang National Laboratory of Solid State Microstructures Department of Materials Science and EngineeringNanjing UniversityNanjing 210093China

An in-situ polymerization method was employed to synthesize the nanosilica/acrylic/epoxy (SAE) hybrid coating on AISI 430 stainless steel (430SS), as compared with a traditional blending method. Mi- crostructures of the blending SAE hybrid coating (BC) and in-situ SAE hybrid coating (ISC) were characterized by transmission electron microscopy (TEM). Corrosion resistance of BC and ISC on 430SS was evaluated by the neutral salt spray test and potentiodynamic polarization technique. Failure mechanism of the BC on 430SS was suggested by the microstructures and corrosion behaviors. Serious aggregation of nanosilica particles in the BC impairs its structural uniformity and induces the flaws formation. These flaws in the BC initiates the failures of pitting, filiform corrosion and peeling which are accelerated by the O2 concentration cell and h+ self-catalysis in chlorine-containing moist environments. The ISC-coated 430SS shows a more advantageous corrosion resistance than that of the BC-coated. The ISC-coated 430SS can suffer the salt spray over 1000 h. Besides, it exhibits a high corrosion potential beyond 0.925 V and good passivation characteristics during the potentiodynamic polarization.

关键词： in-situ polymerization hybrid coating 430 stainless steel (430SS) corrosion resistance failure mechanism

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Expansion of EYM amplitudes in gauge invariant vector space

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Chinese Physics C 2020年第12期44卷 38-71页

作者： Bo Feng Xiao-Di Li Rijun huang zhejiang Institute of Modern Physics Department of PhysicsZhejiang UniversityNo.38 Zheda RoadHangzhou 310027China Institute of Theoretical Physics School of Physics and TechnologyNanjing Normal UniversityNo.1 Wenyuan RoadNanjing 210046China Center of Mathematical Science Zhejiang UniversityNo.38 Zheda RoadHangzhou 310027China

Motivated by the problem of expanding the single-trace tree-level amplitude of Einstein-Yang-Mills theory to the BCJ basis of Yang-Mills amplitudes,we present an alternative expansion formula in gauge invariant vector *** from a generic vector space consisting of polynomials of momenta and polarization vectors,we define a new sub-space as a gauge invariant vector space by imposing constraints on the gauge invariant *** characterize this sub-space,we compute its dimension and construct an explicit gauge invariant basis from *** propose an expansion formula in this gauge invariant basis with expansion coefficients being linear combinations of the Yang-Mills amplitude,manifesting the gauge invariance of both the expansion basis and *** the help of quivers,we compute the expansion coefficients via differential operators and demonstrate the general expansion algorithm using several examples.

关键词： gauge invariance gauge invariant vector space gauge invariant basis EYM amplitudes Yang-Mills amplitudes

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Fabrication of flower-like mesoporous TiO_2 hierarchical spheres with ordered stratified structure as an anode for lithium-ion batteries

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Journal of Materials Science & Technology 2019年第4期35卷 667-673页

作者： Yujie zheng Bingjie Liu Pei Cao hui huang Jing zhang Guowei zhou Key Laboratory of Fine Chemicals in Universities of Shandong School of Chemistry and Pharmaceutical EngineeringQilu University of Technology (Shandong Academy of Sciences)

In this study, flower-like mesoporous TiO_2 hierarchical spheres(FMThSs) with ordered stratified structure and TiO_2 nanoparticles(TNPs) were synthesized via a facile solvothermal route and an etching reaction. Multilamellar vesicles(MTSVs) and unilamellar TiO_2/SiO_2 vesicles(UTSVs) were prepared using cetyltrimethylammonium bromide and didodecyldimethylammonium bromide as structure-directing agents under different solvothermal conditions. FMThSs and TNPs were obtained from the etching reactions of MTSVs and UTSVs, respectively, in an alkaline system. FMThSs display flower-like, ordered stratified structures on each petal. The thickness of the ordered stratified structure is approximately3–6 nm, and the number of layers is approximately 2–4. The FMThSs2 electrode exhibits the first discharge capacity of 212.4 m A h g^(-1) at 0.2 C, which is higher than that of TNPs electrode(167.6 mA h g^(-1)).The discharge specific capacity of FMThSs2 electrode after 200 cycles at 1 C is 105.9 mA h g^(-1), which is higher than that of TNPs electrode(52.2 mA h g^(-1)) after the same number of cycles. The outstanding performance of FMThSs2 electrode is attributed to the advantages of FMThSs. In particular, their own stratified structure can provide additional active sites for reactions. The hierarchical structure can provide short diffusion length for Li^+, large electrolyte–electrode contact area, and superior accommodation of the strain of Li+intercalation/deintercalation.

关键词： Lithium ion batteries Flower-like TiO2 spheres Stratified structure Multialmellar TiO2/SiO2 vesicles Controllable morphology

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Fabrication of Al/Al_2Cu in situ nanocomposite via friction stir processing

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Transactions of Nonferrous Metals Society of China 2017年第4期27卷 779-788页

作者： M.AzIzIEh D.IRANPARAST M.A.G.DEzFULI z.BALAK h.S.KIM Department of Materials Science and Engineering College of Engineering Ahvaz Branch Islamic Azad University Department of Materials Science and Engineering Pohang University of Science and Technology (POSTECH)

The aim of present work is fabrication of Al/Al2Cu in situ nanocomposite by friction stir processing(FSP)as well asinvestigation of FPS parameters such as rotational speed,travel speed,number of FSP passes,and pin profile on the microstructure,chemical reaction,and microhardness of Al based *** Al2Cu particles were formed rapidly due to mechanicallyactivated effect of FSP as well as high heat generation due to Al?Cu exothermic *** microstructure of the nanocompositesconsisted of a finer grained aluminium matrix(~15μm),unreacted Cu nanoparticles(~40nm),and reinforcement nanoparticles *** morphology of Al2Cu is attributed to the local melting during *** diameter has a higher effect on themicrostructure and hardness *** hardness measurements exhibited enhancement by57%compared with the base metal.

关键词： friction stir processing composite materials hardness microstructure surface properties

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Preparation of urea-formaldehyde paraffin microcapsules modified by carboxymethyl cellulose as a potential phase change material

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Journal of Forestry Research 2015年第1期26卷 253-260页

作者： zhan-hua huang Xin Yu Wei Li Shou-xin Liu Key Laboratory of Bio-based Material Science and Technology Ministry of EducationNortheast Forestry University

We prepared spherical microcapsules modified by carboxymethyl cellulose（CMC） with urea-formaldehyde（UF） resin as a shell material with a two-step process by in situ polymerization, and characterized the microcosmic features, chemical structure, and thermal performance of the microcapsules by SEM, FTIR, DSC, and TGA. We studied the effects of different experimental parameters of curing p h, the amounts of the emulsifier and emulsion speed. The CMC-UF microcapsules had good heat resistance and stability. The enthalpy of CMC-UF microcapsules reached 50.33 J g-1. Therefore, CMC-UF resin can be used as a potential wall material of phase change materials.

关键词： Spherical microcapsules Carboxymethyl cellulose Energy storage

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Effect of Temperature on Gene Expression in the Pearl Oyster Pinctada fucata

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Journal of Ocean University of China 2014年第3期13卷 509-515页

作者： LIU Wenguang huang Xie LIN Jianshi hE Maoxian CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology South China Sea Institute of OceanologyChinese Academy of Sciences

In this study, we examined the effect of elevated temperature on the expression patterns of genes, i.e., nacrein, irr, n16, n19, and hsp70 in the pearl oyster Pinctada fucata. The experiment was carried out at 4 temperatures, i.e., 20℃(ambient, control), 24, 28℃, and 32℃. The expression levels of target genes in P. fucata were assayed at 0, 6, 24, 48, and 96 h via real-time polymerase chain reaction. Results showed that the expression levels of nacrein and irr had no significant variations among different time points below 28℃, but significantly increased over time at 32℃. The expression levels of n16 and n19 did not change markedly at 20℃. The former increased significantly at 6 h and 24 h while the latter substantially decreased during 6–96 h at 24, 28 and 32℃. Among different temperatures, the level of n16 was significantly lower at 20℃ than at other temperatures during 6–96 h, and the level of n19 significantly varied among different temperatures at 48 h and 96 h. The expression level of hsp70 was significantly higher at 32℃ than at 20, 24 and 28℃ at 24 h. These results demonstrated that elevated temperature impacted the physiological processes of P. fucata and potentially influenced its adaptability to thermal stress.

关键词： seawater temperature heat shock protein gene expression pattern Pinctadafucata

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ALTERNATING DIRECTION IMPLICIT SChEMES FOR ThE TWO-DIMENSIONAL TIME FRACTIONAL NONLINEAR SUPER-DIFFUSION EQUATIONS

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Journal of Computational Mathematics 2019年第3期37卷 297-315页

作者： Jianfei huang Yue zhao Sadia Arshad Kuangying Li Yifa Tang College of Mathematical Sciences Yangzhou UniversityYangzhou 225002China LSEC ICMSECAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China COMSATS Institute of Information Technology LahoTePakistan McDougall School of Petroleum Engineering The University of TulsaTulsaOK 74104USA

As is known,there exist numerous alternating direction implicit(ADI)schemes for the two-dimensional linear time fractional partial differential equations(PDEs).however,if the ADI schemes for linear problems combined with local linearization techniques are applied to solve nonlinear problems,the stability and convergence of the methods are often not *** this paper,two ADI schemes are developed for solving the two-dimensional time fractional nonlinear super-diffusion equations based on their equivalent partial integrodifferential *** these two schemes,the standard second-order central difference approximation is used for the spatial discretization,and the classical first-order approximation is applied to discretize the Riemann-Liouville fractional integral in *** solvability,unconditional stability and L2 norm convergence of the proposed ADI schemes are proved *** convergence order of the schemes is 0(τ+hx^2+hy^2),where τ is the temporal mesh size,hx and hy are spatial mesh sizes in the x and y directions,***,numerical experiments are carried out to support the theoretical results and demonstrate the performances of two ADI schemes.

关键词： Time fractional super-diffusion equation Nonlinear system ADI schemes Stability Convergence

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Robust Frequency Estimation Under Additive Mixture Noise

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Computers, Materials & Continua 2022年第7期72卷 1671-1684页

作者： Yuan Chen Yulu Tian Dingfan zhang Longting huang Jingxin Xu School of Computer and Communication Engineering University of Science&Technology BeijingBeijing100083China School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191China School of Information Engineering Wuhan University of TechnologyWuhan430070China Department of Energy and Public Works Queensland4702Australia

In many applications such as multiuser radar communications and astrophysical imaging processing,the encountered noise is usually described by the finite sum ofα-stable(1≤αhis paper,a new parameter estimator is developed,in the presence of this new heavy-tailed *** the closed-formPDF of theα-stable variable does not exist exceptα=1 andα=2,we take the sum of the Cauchy(α=1)and Gaussian(α=2)noise as an example,namely,additive Cauchy-Gaussian(ACG)*** probability density function(PDF)of the mixed random variable,can be calculated by the convolution of the Cauchy’s PDF and Gaussian’s *** of the complicated integral in the PDF expression of the ACG noise,traditional estimators,e.g.,maximum likelihood,are analytically not *** obtain the optimal estimates,a new robust frequency estimator is devised by employing the Metropolis-hastings(M-h)***,to guarantee the fast convergence of the M-h chain,a new proposal covariance criterion is also devised,where the batch of previous samples are utilized to iteratively update the proposal covariance in each sampling *** simulations are carried out to indicate the superiority of the developed scheme,when compared with several conventional estimators and the Cramér-Rao lower bound.

关键词： Frequency estimation additive cauchy-gaussian noise voigt profile metropolis-hastings algorithm cramér-rao lower bound

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