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Fluid Inclusions and Daughter Minerals of Taibai Gold Deposit, ShaanXi Province, china

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Journal of university of science and technology beijing 2001年第1期8卷 6-9页

作者： YulingXie, Jiuhua Xu, dayi qian, Jianping Li Resources Engeneering School, university of science and technology beijing, beijing 100083, china Univ Sci & Technol beijing Resources Engn Sch Beijing 100083 Peoples R China

A discovery of daughter minerals in fluid inclusions of Taibai gold deposit, Shaanxi province has been focused on, which is a unique breccia-cemented gold-bearing system. The breccia zone strikes NWW-SEE, occurring in Devonian strata of Southern Qinling Mountains. The cement is mainly composed of ankerite, pyrite, calcite and quartz, which may be divided into four main tectonic-mineralizing stages. Gold mainly occurs in pyrite and ankerite of stage II and IV. It is found that three types of fluid inclusions can be distinguished: (1) aqueous inclusions (type B); (2) CO2-rich inclusions (type C); (3) daughter minerals-containing inclusions (type A). LRM. (Laser Raman Micro-probe) analyses shows that the content of CO2 occupies 54.4%-70.7% (mole fraction, so as the follows) in vapor phases of different type fluid inclusions. CH4 (5.2%-7.3%) and H2S (6.0%-12.7%) exist in both vapor and liquid phases. Many daughter minerals in fluid inclusions of ankerite and quartz have been found. Several kinds of daughter minerals, including ankerite, pyrite, arsenopyrite and halite, were determined by using SEM (scanning electron microscope)/EDS (energy dispersive spectrometer) technique. EPMA (electron probe micro-analysis) technique was also applied to study the daughter minerals exposed to the surface of polished thin sections.

关键词： daughter minerals fluid inclusions gold deposit breccia

Characteristics of Ore-Forming Fluids of Gold Deposits in Daqingshan District,Inner Mongolia,china

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International Journal of Minerals,Metallurgy and Materials 1999年第2期13卷 77-82页

作者： Jiuhua Xu YulingXie dayi qian Rufu Dine Jianping Li (Resource Engineering School, university of science and technology Beijha beijing 100083, china) (china university of Geosciences, beijing 100083, china) Resource Engineering School University of Science and Technology Beijing Beijing 100083 China china university of Geosciences Beijing 100083 China

***-weststrikingductileshearzonewithinagreelt,***:(1)pyrite-quartz,(2)quartz-Pyrite,(3)polymetallicsulfidesand(4)***-bearingveinsarenativegold,electrum,pyrite,chalcopyriteandgalena,buttheganguemineralsaremainlyquartz,secondarilysericite,***,silicification,***-formingfluidswerelowinsalinitieandhighinCO2content,MeasuredδDoffluidinclusionsinquartzfromtheoreveinsrangesfrom-65‰to-104‰,butδ18Oquartzfrom10.0‰to12.8‰.Thesedatashowthatthewaterinhydrothermalfluidprecipitatingtheorebodiescouldhavebeenmainlymagmaticwaterandmetamorphicwaterbutlocalmeteoricwatermighttakepartinthelatemineralization.δ13Cfromfl

关键词： fluid inclusions isotope composition gold deposit Daqingshan area

Effects of Na/K ratio on the phase structure and electrical properties of Na_xK_(1-x)NbO_3 lead-free piezoelectric ceramics

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Rare Metals 2010年第2期29卷 220-225页

作者： ZHANG qian, ZHANG Boping, Li Haitao, and SHANG Pengpeng School of Materials science and Engineering, university of science and technology beijing, beijing 100083, china School of Materials science and Engineering University of Science and Technology Beijing

Lead-free piezoelectric NaxK1-xNbO3（x = 0.3-0.8）（NKN） ceramics were fabricated by normal sintering at 1060°C for 2 *** and electrical properties of the ceramics were investigated with a special emphasis on the influence of Na *** grain size of the produced dense ceramic was decreased by increasing Na content.A discontinuous change in the space distance was found at the composition close to Na0.7K0.3NbO3 ceramic, which indicates the presence of a transitional composition between two different orthorhombic phases, which is similar to the behavior of morphotropic phase boundary（MPB） in NaxK1-xNbO3 *** MPB-like behavior contributes to the enhanced piezoelectric coefficient d33 of 122 pC/N, planar-mode electromechanical coupling coefficient kP of 28.6%, and dielectric constant εr of 703, respectively for the Na0.7K0.3NbO3 *** temperature TC and the transitional temperature TO-T from orthorhombic to tetragonal phase are observed at around 420°C and 200°C, respectively.

关键词： lead-free piezoelectric ceramics NKN sintering morphotropic phase boundary(MPB)

Application of Single Neuron Adaptive PID Regulators with Auto-tuning Gain in Industrial Parameter(Pressure)Closed-loop Process Control Systems

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International Journal of Minerals,Metallurgy and Materials 1999年第2期13卷 152-153页

作者： Shaoyuan Sun Huade Li Bin qian Jianping Wei(Information Engineering School, university of science and technology beijing, beijing 100083, china) Information Engineering School University of Science and Technology Beijing Beijing 100083 China

A type of single neuron adaptive PID regulator with auto-tuning gain is proposed and applied to the work control of fans, waterpumps and air-pressers etc. in Handan Iron & Steel Compel china. The robusthess of induStr... 详细信息

关键词： single neuron gain adaptiVe PID regulator pressure closed-loop control

Autonomous relative optical navigation based on unified modeling of external systematic errors

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Chinese Journal of Aeronautics 2024年第3期37卷 282-289页

作者： dayi WANG Bowen SUN Maodeng LI Jiaxing LI Haiyin ZHOU beijing Institute of Spacecraft System Engineering Beijing 100191China College of sciences National University of Defense TechnologyChangsha 410073China National Key Laboratory of Space Intelligent Control Beijing Institute of Control EngineeringBeijing 100191China

To solve the problem that external systematic errors of the optical camera cannot be fully estimated due to limited computing resources,a unified dimensionality reduction representation method for the external systematic errors of the optical camera is proposed,and autonomous relative optical navigation is *** camera translational and misalignment errors are converted into a three-dimensional rotation error,whose differential model can be established through specific attitude control and appropriate ***,the rotation error and the relative motion state are jointly estimated in an augmented Kalman filter *** with the traditional method that estimates the camera translational and misalignment errors,the proposed method reduces the computational complexity in that the estimated state dimension is ***,as demonstrated by numerical simulation,the estimation accuracy is improved significantly.

关键词： Unified model Systematic errors Optical navigation Observability analysis Calibration

Services Discovery for Distributed Network Measurement

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计算机工程 2002年第S1期28卷 28-32页

作者： LI Wei, qian DepeiLI Yunchun, SHI Nayan(Dept. of Computer science &technology,beijing university of Aeronautics &Astronautics,beijing 100083,china) Dept. of Computer science &technology Beijing University of Aeronautics &AstronauticsBeijing 100083China

More and more distributed applications are deployed around interconnected network, which makes it necessary for network measurement services to address the scalability and robustness requirements. This paper discusses a service discovery forintegrated network measurement architecture (INMA), including finding the location of measurement agent, the path of the measurement and the network attributes of the end-to-end path or host. It also describes the functions of the major building blocks used to construct the measurement architecture.

关键词： Service discovery Network measurement Directory server

An atomistic simulation of site preference and vibrational properties of UMxAl12-x (M = Fe, Co, Ni, Cr and Mn) and UMxAl12-xHx

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Progress in Natural science:Materials International 2009年第8期19卷 983-989页

作者： Huijun Tian a,b, Ping qian a, Jiang Shen a, Nanxian Chen a,c a Institute of Applied Physics, beijing university of science and technology, beijing 100083, china b School of Physics, beijing university of Chemical technology, beijing 100029, china c Department of Physics, Tsinghua university, beijing 100084, china [a]Institute of Applied Physics Beijing University of Science and Technology Beijing 100083 China [b]School of Physics Beijing University of Chemical Technology Beijing 100029 China [c]Department of Physics Tsinghua University Beijing 100084 China

A series of lattice inversion pair potentials are used to evaluate the phase stability and site preference for uranium intermetallics UMxAl12 x (M = Fe, Co, Ni, Cr and Mn) and their related hydrides. Calculated results show that Fe, Co, Ni, Cr or Mn atoms preferentially substitute Al at the 8f site. Interstitial H atoms only occupy 2b interstitial sites in UMxAl12 x. Calculated lattice constants are found to agree with a report in the literature. Elastic constants and bulk modulus of UMxAl12 x and UMxAl12 xH were also investigated. In particular, the phonon densities of states (DOS) of these actinide compounds were evaluated for the first time.

关键词： Interatomic potentials Site preference Lattice vibration

Comparative analysis of DNA-SIP and magnetic-nanoparticle mediated isolation (MMI) on unraveling dimethoate degraders

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Frontiers of Environmental science & Engineering 2024年第1期18卷 59-69页

作者： Luning Lian Yi Xing dayi Zhang Longfei Jiang Mengke Song Bo Jiang School of Energy and Environmental Engineering University of Science&Technology BeijingBeijing 100083China beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants University of Science&Technology BeijingBeijing 100083China National Environmental and Energy science and technology International Cooperation Base University of Science&Technology BeijingBeijing 100083China College of New Energy and Environment Jilin UniversityChangchun 130021China Guangzhou Institute of Geochemistry Chinese Academy of SciencesGuangzhou 510640China College of Natural Resources and Environment South China Agricultural UniversityGuangzhou 510642China National Engineering Laboratory for Site Remediation Technologies Beijing 100015China

Microorganisms are crucial in the bioremediation of organophosphorus pesticides. However, most functional microorganisms (> 99%) are yet to be cultivated. This study applied two cultivation-independent approaches, DNA-SIP and magnetic-nanoparticle mediated isolation (MMI), to identify the functional microorganisms in degrading dimethoate in agricultural soils. MMI identified five dimethoate degraders: Pseudomonas, Bacillus, Ramlibacter, Arthrobacter, and Rhodococcus, whereas DNA-SIP identified three dimethoate degraders: Ramlibacter, Arthrobacter, and Rhodococcus. Also, MMI showed higher resolution than DNA-SIP in identifying functional microorganisms. Two organic phosphohydrolase (OPH) genes: ophC2 and ophB, were involved in dimethoate metabolism, as revealed by DNA-SIP and MMI. The degradation products of dimethoate include omethoate, O,O,S-trimethyl thiophosphorothioate, N-methyl-2-sulfanylacetamide, O,O-diethyl S-hydrogen phosphorodithioate, O,O,O-trimethyl thiophosphate, O,O,S-trimethyl thiophosphorodithioate, and O,O,O-trimethyl phosphoric. This study emphasizes the feasibility of using SIP and MMI to explore the functional dimethoate degraders, expanding our knowledge of microbial resources with cultivation-independent approaches.

关键词： Stable isotope probing(SIP) Magnetic-nanoparticle mediated isolation(MMI) Dimethoate Biodegradation Cultivation-independent approach

Effect of Temperature and Cl^- Concentration on Pitting of 2205 Duplex Stainless Steel

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Journal of Wuhan university of technology(Materials science) 2011年第4期26卷 641-647页

作者：董超芳 Corrosion and Protection Center University of Science and Technology Beijing

The electrochemical behaviors of 2205 duplex stainless steel in NaCl solution with different temperatures and concentrations were studied by gravimetric tests, potentiodynamic polarization, electrochemical impedance spectroscopy and scanning electron microscopy. The experinental results show that temperature and chloride concentration have a great influence on the pitting resistance of 2205 duplex stainless steels. They not only effect the corrosion rate of pitting, but also change the shape of the pits. When NaCl solution was in low concentration and temperature below the critical pitting temperature, pits were very small and scattered with hemisphere-like shape. On the contrary, the pits of 2205 duplex stainless steel were large and sometimes had a lacy cover when the NaCl concentration was higher and the temperature was 70℃.

关键词： 2205 duplex stainless steel pitting temperature chloride