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A Monte Carlo study of the spectra from inhomogeneous accretion flow

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Research in Astronomy and Astrophysics 2017年第8期17卷 101-108页

作者： Xiao-Di Yu Ya-Ping Li Fu-guo xie Ren-Yi Mai Department of Astronomy and Institute of Theoretical Physics and Astrophysics Xiamen University Xiamen 361005 China Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academyof Sciences Shanghai 200030 China SHAO-XMU Joint Center for Astrophysics Xiamen 361005 China

A model of an inhomogeneous accretion flow,in which cold clumps are surrounded by hot gas or corona,has been proposed to explain the spectral features of black hole X-ray *** this work,we try to find possible observational features in the continuum that can indicate the existence of *** spectra of an inhomogeneous accretion flow are calculated via the Monte Carlo *** the corresponding accretion flow is unsteady and complex,the accretion flow is described by a set of free parameters,the ranges of which can include the real *** influences of the parameters are *** is found that the thermal component of the spectra deviates from multi-color black body spectra in the middle power-law *** one hand,a warp appears due to the gaps between the clumps and the outer cold disk,and on the other hand,the slope of the line connecting the thermal peaks deviates from 4/*** warp feature,as well as the correlation between the thermal peak at higher frequency and the spectral index,possibly indicate the existence of clumps,and are worthy of further investigation with more self-consistent models.

关键词： accretion accretion disks—X-rays binaries—stars black holes

Precipitation process and its effects on properties of aging Cu–Ni–Be alloy

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Rare Metals 2013年第4期32卷 332-337页

作者： Li-Jun Peng Bai-Qing Xiong guo-Liang xie Qiang-Song Wang Song-Bai Hong State Key Laboratory of Nonferrous Metals & Process General Research Institute for Nonferrous Metals Yingtan Shine Electric Metal Material Co. Ltd

The precipitation process of aged Cu-Ni-Be alloy was investigated by X-ray diffraction （XRD）, trans- mission electron microscopy （TEM）, and high-resolution transmission electron microscopy （HRTEM）. The tensile strength, yield strength, and electronic conductivity of this alloy after aging were also studied. The precipitation sequence of the C17510 alloy aged at 525 ℃ is supersat-urated solid solution→G.P zones→ γ″-γ′→ γ. This transformation can be achieved by the accumulation of Be-atom layers. The G.P zones are composed of disk-shaped monolayers of Be atoms, which are formed on （001） matrix planes. The intermediate γ″ precipitate is nucleated in the G.P zones. The γ″ and γ′ precipitates have the same orientation relationship with matrix, e.g., （110）p｜｜（100）M,[001]p｜｜[001]M. The tensile strength of specimen shows a maximum during the aging process and then continuously decreases if the specimen is over aged. The strengthening effect of γ′ phase precipitated in aging at 525 ℃ for 4 h is calculated to be 436 MPa according to the Orowan strengthening, which is quite consistent with the experimental data.

关键词： Precipitation process C17510 alloy Metastable phases Strengthening mechanism

Enhanced Mechanical Properties, Corrosion Behavior and Bioactivity of Ti-based Bulk Metallic Glasses with Minor Addition Elements

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Acta Metallurgica Sinica(English Letters) 2016年第11期29卷 1011-1018页

作者： Feng-Xiang Qin Yang Zhou Chuan Ji Zhen-Hua Dan guo-Qiang xie Sen Yang School of Materials Science and Engineering Nanjing University of Science and Technology Nanjing 210094China College of Materials Science and Engineering Nanjing TECH University Nanjing 210009 China Institute for Materials Research Tohoku University Sendai 980-8577 Japan

In this research, corrosion behavior, mechanical properties and bioactivity of Ti–Zr–Cu–Pd–Sn bulk metallic glasses with minor addition of Au, Pt, Nb or Ta elements were investigated. The results revealed that minor additions of the elements were beneficial to enhancing mechanical properties and corrosion resistance of Ti-based bulk metallic *** addition of the element（especially with Nb and Ta addition） results in the improvement in plastic deformation ability due to the existing of nanoparticles with a size smaller than 10 nm in glassy matrix, inhibiting the deformation of the shear bonds. Enrichments of Ti and Zr elements in oxide layer were responsible for high corrosion resistance. The bioactivity of Ti-based bulk metallic glasses was also investigated. The best combination of large plastic deformation ability, good corrosion resistance and bioactivity in Ti40Zr10Cu33Pd（14）Sn2Ta1 BMG was obtained.

关键词： Bulk metallic glass Microstructure Alloy design Corrosion Mechanical behavior Biocompatibility

Fluorometric determination of nonylphenol in water samples enriched with zirconium doped titanium dioxide nanotubes solid phase extraction

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Chinese Chemical Letters 2012年第8期23卷 969-972页

作者： Xian Fa Su Xin Ning Zhao guo Hong xie Qing Xiang Zhou School of Chemistry and Environmental Sciences Henan Normal UniversityXinxiang 453007China Environmental Protection Agency of Xinxiang City Xinxiang 453000China College of Resources and Environment Henan Institute of Science and TechnologyXinxiang 453003China College of Geosciences China University of PetroleumBeijing Campus(CUP)Beijing 102249China

This paper developed a fluorometric method for the sensitive determination of nonylphenol in water samples by preconcentration with zirconium doped titanium dioxide nanotubes solid phase *** parameters on extraction that would influence the enrichment performance such as the kind and volume of eluent,sample pH,sample flow rate,and sample volume were optimized in *** the optimal conditions,the proposed method provided an excellent linear range of 1-150 mg/L and good LOD of 0.076 mg/*** relative standard deviation（RSD,n = 6） was 2.8%.Proposed method was also used for the analysis of real water samples and the spiked recoveries were satisfied in the range of 98.7-103%.

关键词： Zirconium doped TiO2 nanotubes Nonylphenol Solid phase extraction Water samples

TiO_2 nanotubes:A novel solid phase extraction adsorbent for the sensitive determination of nickel in environmental water samples

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Chinese Chemical Letters 2008年第7期19卷 865-867页

作者： Xin Ning Zhao Qi Zeng Shi guo Hong xie Qing Xiang Zhou School of Chemistry and Environmental Sciences Henan Normal University Henan Key Laboratory for Environmental pollution Control Key Laboratory for Yellow River and Huaihe River Water Environment and Pollution Control Ministry of Education Xinxiang 453007 China College of Resources and Environment Henan Institute of Science and Technology Xinxiang 453003 China

A novel method was developed for the sensitive determination of nickel in environmental water samples by using TiO2 nanotubes, a new nanomaterial, as solid phase extraction absorbent. In general, TiO2 nanomaterials were often used for catalytic degradation of pollutants in environmental field, and only a very few application in environmental analytic chemistry. In present work, TiO2 nanotubes was firstly used for the enrichment of nickel and the factors would influence the preconcentration performance were optimized. Under the optimal conditions, TiO2 nanotubes exhibited its good enrichment capacity for nickel and the detection limit of the proposed method was 1 ng· mL^-1. The proposed method was validated with real water samples, and excellent results were obtained with the spiked recoveries in the range of 94.4-99.2%, respectively.

关键词： TiO2 nanotubes Nickel Flame atomic absorption spectrometry

Experimental Study into Permeability of Broken Mudstone

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Journal of China University of Mining and Technology 2007年第2期17卷 147-151页

作者： MA Zhan-guo MIAO xie-xing ZHANG Fan LIYu-shou School of Sciences China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Much attention should be paid to the permeability of broken rocks in goafs for the sake of water preservation in mining and to prevent disasters. Using a special device together with the MTS815.02 Rock Mechanics Test System,we tested the permeability of broken mudstone during its compacting process,and obtained the relations between axial stress and differential seepage pressure and between the pressure gradient and the seepage velocity. The effect of axial stress,grain size,and seepage velocities on the permeability coefficient is analyzed. The results show that 1) permability varies abruptly when the load reaches the compressive strength of rock samples,2) for a constant seepage velocity,the differential seepage pressure and the axial stress can be expressed by an exponential function,3) for a constant axial stress,the pressure gradient and the seepage velocity can be also expressed by an exponential function and 4) the permeability coefficient of broken mudstone of different sizes is closely related to its compaction state and will decrease with the increase of axial stress,expressed as a logarithmic function.

关键词： rock mechanics broken mudstone axial stress seepage properties test

Application of quantification theory in risk assessment of mine flooding

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Journal of China University of Mining and Technology 2008年第1期18卷 38-41页

作者： WANG Lian-guo MIAO xie-xing DONG Xu WU Yu School of Sciences China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Hundreds of mine flooding accidents have occurred in China since the 1950s. These flooding accidents result in submerged working faces, even entire coal mines, leading to tremendous economic losses. It is reported that among 601 state-owned mines in China, 285 mines are exposed to water-inrush risks. The water pressure is becoming larger and larger with the increase of mining depth, leading to an increase of water-inrush hazards. Only when the risk of mine flooding is predicted in a reasonable manner, can we take timely and effective measures to prevent mine flooding from taking place. In our investigation quantification（H） theory is used to study the risk prediction problem about mine flooding. By investigating the main factors which affect mine flooding, eight risk assessment items have been identified. The extent of risk is classified into 4 grades. Given the data from different periods in the Feicheng mining area, a prediction model for the risk of mine flooding is established. The test analysis indicates a model correlation coefficient of 0.97 and the incidence of discrimination is as high as 97.37%, which implies that the effect of the model is quite satisfactory. With the help of computers, this method can be widely applied.

关键词： mine flooding quantification(II) theory prediction model assessment item

Electric Load Forecasting for Shanghai Urban Area

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Advances in Manufacturing 2000年第2期4卷 128-132页

作者： guo-dong1 xie Su-rong Huang Fang-long Xu guo-fang Gong School of Electromechanical Engineering and Automation Shanghai University Shanghai 200072 China Shanghai Urban Power Supply Bureau Shanghai 200080 China

In this paper electric load is forecast for the classified power consumers of Shanghai urban area for the scheduled years in short term and in long term respectively. The monthly load in 1999 is forecast on the basis of the data during 1992～1998, and the approximate load in 2010 is forecast on the basis of the data during 1990～1998.

关键词： load forecasting mathematical model trend forecasting

Synthesis and photochemistry of novel bromo substituted stilbene derivatives as triplet state sensitizers for the generation of singlet oxygen

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Chinese Chemical Letters 2009年第12期20卷 1415-1418页

作者： Hong Ru Li Qin Yuan guo Ting xie Fang Gao Sheng Tao Zhang College of Chemistry and Chemical Engineering Chongqing University Chongqing 400044 China

We have presented the synthesis and characterization of three new bromo substituted stilbene derivatives, p-3,4,5-trimethoxy-p′- 2,3,4,5,6-pentabromostilbene （C1）, p-N,N-dimethylamino-p′-2,3,4,5,6-pentabromostilbene （C2） and p-N,N-diphenylamino-p′- 2,3,4,5,6-pentabromostilbene （C3） in this letter. The UV/vis absorption and photoluminescence were investigated in various solvents. The maximal absorption wavelength of C1 exhibited blue-shift to those of C2 and C3 in different solvents. No florescence emission could be detected for these compounds at room temperature. Singlet oxygen could be efficiently produced with these sensitizers under near-ultraviolet and visible light irradiation.

关键词： Synthesis Photochemistry Triplet state Bromo substitution Singlet oxygen