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Effect of Post-spinning Modification on the PAN Precursors and Resulting Carbon Fibers

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Journal of Wuhan University of technology(Materials Science) 2006年第3期21卷 44-48页

作者：张旺玺 department of Mechanics engineering Zhongyuan Institute of TechnologyZhengzhou 450070China

The impregnation of a special grade PAN precursor,fibers wus carried out in a 8 wt% KMnO4 aqueous solution to obtain modified PAN precursor fibers. The effects of modification on the chemical stncture and the mechanical properties of precursor fibers thermally stabilized and their resulting carbon fibers u＇ere characterized by the combiination use of densities, wide-angle X-ray diffraction （WAXD）, X-ray photoelectron speetroscopy （XPS）, elemental analysis （ EA ）, Fourier traasform infrared spectroscopy （FT-IR） and scanning electron microscope （SEM）, ***4 as a strong oxidizer can swell, oxidize and corrode the skin of a ***, and transform C≡N groups to C≡N ones, meamchile , it can decreuse the crystal .size increuse the orientation index and the costallinity index, furthermore it can increuse the densities of modified PAN precursors and resuhing thermally stabilized fibers. As a result, the carbon fibers developed from modified PAN fibers show an improvement in tensile strength of 31.2. % and an improvement in elongation of 77.78 % , but a decrease of 16. 52. in Young＇s modulus.

关键词： carbon fibers carbon precursor chemical treatment mechanical properties

Solving the input data in error correc-tion of optical fabrication by finite Fourier coefficient algorithm

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Science china(Technological Sciences) 2006年第1期49卷 50-60页

作者： CHENG Haobo1,2. SUN Guozheng3 & FENG Zhijing2.1. department of Optical engineering, Beijing {2. of technology, Beijing 100081, china 2. department of Precision Instruments and Mechanology, Tsinghua University, Beijing 100084, china 3. china North Industries Group Corporation, Beijing 100089, china 1. department of Optical engineering Beijing Institute of Technology Beijing 100081 China 2. department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China 3. china North Industries Group Corporation Beijing 100089 China

A free-form lens (FFL) is a special surface that is difficult to be fabricated. FFL are usually fabricated by computer-controlled optical surfacing (CCOS) technique. During CCOS, the material removal amount is determined by the unit removal function (URF) convoluting with the input data――the dwell time. When the removal amount and the URF are known, how to solve the input data involves the special algorithm――deconvolution. Usually, the input data are solved by virtue of low pass filter or iterative methods. However, an approximation solution would destroy the machining stability nec-essary to perform precisely CCOS. In this paper, to solve the input data, a new method that is based on the finite Fourier coefficient is put forward. It can give a continuous and accurate solution for fabricating choice. Several parameters are simulated, which influ-ence the process of CCOS, and evaluating on the effect of the method is also carried out. Experimental results verify that this method is suitable for guiding the manufacturing of high precision FFL.

关键词： optical fabrication, computer controlled optical surfacing, free-form lens, finite Fourier coefficient, error correction.

Coupling analysis of unsteady seepage and stress fields in discrete fractures network of rock mass in dam foundation

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Science china(Technological Sciences) 2011年第S1期54卷 133-139页

作者： CHAI JunRui 1,2.& XU WeiSheng 2.1 College of Hydraulic and environmental engineering,{2. Three Gorges University,Yichang 443002.{2. 2.College of Hydropower engineering,Xi’an University of technology,Xi’an 710048,{2. 1. College of Hydraulic and environmental engineering China Three Gorges University Yichang 443002 China2. College of Hydropower Engineering Xi’an University of Technology Xi’an 710048 China

The drag force of water flow through single fracture and the coupling characteristics of seepage and stress in single fracture surface are analyzed,and a three dimensional model of coupled unsteady seepage and stress fields is *** model is used to the analysis of foundation rock mass of a high *** the coupling effects are considered,the changes of boundary heads have less influence on the inner head of rock mass,and the strong permeability of main fractures *** the coupling effects are not considered,the fractures distribution affects the inner head more *** the upstream water head declines,the inner head of dam foundation slightly declines and the hydraulic gradient distribution becomes smoother.A bigger upstream water level declining velocity has a stronger lag effect,meanwhile the values of stress components change more *** the upstream water level declining velocity directly affects the stability of rock mass in dam foundation and we should take into account the above factors to make sure the safety of the dam during reservoir level fluctuation period.

关键词： hydraulic engineering unsteady seepage stress coupling fractures network rock mass

Morphology and electrical conductivity of PACS

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Journal of environmental Sciences 2000年第3期12卷 319-324页

作者： GAO Bao\|yu\+1, LIU Zong\|gang\+2. YUE Qin\|yan\+3, ZHAO Hua\|zhang\+3 (1. department of environmental {2., Shandong University, Jinan 2.0100, china 2. environmental Monitoring Station of Huaiyin, Jinan 2.002., china 3. department of Environ 山东大学山东济南 2 50 1 0 0 山东济南市槐荫区环境监测山东济南 2 50 0 2 2

Polyaluminium chlorides with sulfate ion(PACS) were prepared by using AlCl 3·6H 2., Al(SO 4) 3·18H 2. and Na 2.O 3 as raw materials. The effects of basicity ( r ), Al 3+ /SO 4 2. molar ratio and aging time on the morphology of PACS were observed by transmission electrical microscope. The influence of aging time on charge neutralization and coagulation effect of PACS was studied. The effects of basicity ( r ), Al 3+ /SO 4 2. molar ratio and aging time on the electrical conductivity of PACS solution were also investigated. The experimental results show that the degree of polymerization of polyaluminium chloride(PAC) increases when SO 4 2. ion is added. The higher the basicity( r ) and the longer the aging time, the larger the size of polymer PACS. The ability of PACS neutralizing the charge on Kaolinite decreases with the increase of aging time. The electrical conductivity of PACS solution(the concentration of Al 3+ ion is 0.18 mol/L) with different aging time is the function of the basicity and Al 3+ /SO 4 2. molar ratios and has its maximum at r =0.5 and Al 3+ /SO 4 2. =12.

关键词： coagulant PACS morphology transmission electron microscope electrical conductivity coagulation

A STOCHASTIC MICROMECHANICAL MODEL FOR EFFECTIVE PROPERTIES OF FUNCTIONALLY GRADED MATERIALS

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A STOCHASTIC MICROMECHANICAL MODEL FOR EFFECTIVE PROPERTIES ...

Bipolar charged aerosol agglomeration and collection by a two-zone agglomerator

第二届亚洲功能材料与结构力学大会

作者： Li-cheng Guo~1 Zhi-hai Wang~2.Ji-cai Feng~3 1 department of Material Science and engineering & department of Astronautic Science and Mechanics harbin institute of technology harbin 150001 Chin 2.department of Astronautic Science and Mechanics harbin institute of technology harbin 150001 china 3 department of Material Science and engineering harbin institute of technology harbin 150001 Chin

＜正＞For actual functionally graded materials（FGM）,the effective properties evaluated by theoretical models often disagree with measured *** distributions of their effective properties may be very complex as considerable randomness can be observed from sample to *** factors should be considered in analyzing the effective properties of *** this paper,an analytical method is proposed to obtain effective properties of FGM with stochastic uncertainties in phase volume *** stochastic characteristics of phase volume fractions can be described by random *** investigate how the effective properties are related to the stochastic uncertainties in phase volume fractions,the probability theory is *** using the probability theory the probabilistic characteristics of effective properties can be *** results show that the influence of the probabilistic characteristics of phase volume fractions on the effective properties of FGM is obvious and should be considered in some cases.

关键词： Functionally graded material(FGM) effective properties probabilistic characteristics

来源： cnki会议评论

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cnki会议

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Journal of environmental Sciences 2001年第3期13卷 276-279页

作者： XIANG Xiao dong 1, CHEN Bao zhi 1, COLBECK I 2.(1. School of Resource and Civil engineering, Northeastern University, Shenyang 110006, china. 2. {2. for environmental Research, department of Biological and Chemical Sciences, University of Es School of Resource and Civil engineering Northeastern University Shenyang 110006 China.

In older to collect fine particles more efficiently, a new-type electrostatic agglomerator with two zones was developed. The distinguishing feature of this electrostatic agglomerator is that the particles are bipolarly charged and coagulated in the same alternating electric field simultaneously. The silica flour with 2.fun mass median diameter and the smoke from burning wood powder were used as test aerosol. The comparison experimental results have shown that when the mean electric field is 4 kV/cm the collection efficiency of the new electrostatic agglomerator was 98.2. for silica flour and 67.4% for wood powder smoke, Under the same experimental condition. the collection efficiency of the electrostatic agglomerator with three zones was 97.4% for collecting silica flour and the collection efficiency of the electrostatic precipitator was 56.3% for wood powder smoke.

关键词： charged particle agglomeration alternating electric field electrostatic agglomerator (EA) electrostatic precipitator (ESP) collection efficiency

A feature ensemble technology to identify molecular mechanisms for distinction between multiple subtypes of lymphoma

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Progress in Natural Science:Materials International 2008年第12期18卷 1491-1500页

作者： Yueying Yang~(a,1) Haiyun Wang~(a,b,1) Xia Li~(a,b,c) Xue Xiao~c Su Fei~a Chuanxing Li~a Hongzhi Wang~d Shaoqi Rao~(a,c,e) Yadong Wang~d a College of Bioinformatics Science and technology,Bio-pharmaceutical Key Laboratory of Heilongjiang Province and State,harbin Medical University,harbin 150081,china b College of Life Science and technology,Tongji University,Shanghai 2.0092.china c The Biomedical engineering institute,Capital Medieal University,Beijing 100054,china d department of Computer Science,harbin institute of technology,harbin 150080,china e department of Molecular Cardiology,Cheveland Clinic Foundation,Cleveland,OH 44195,USA [a]College of Bioinformatics Science and technology Bio-pharmaceutical Key Laboratory of Heilongjiang Province and State Harbin Medical University Harbin 150081 China [b]College of Life Science and technology Tongji University Shanghai 200092 China [c]The Biomedical engineering institute Capital Medical University Beijing 100054 China [d]department of Computer Science Harbin Institute of Technology Harbin 150080 China [e]department of Molecular Cardiology Cleveland Clinic Foundation Cleveland OH 44195 USA

Due to complexities and genetic heterogeneities of biological phenotypes,robust computational approaches are desirable to achieve high generalization performance with multiple classifiers,perturbations of the data structures,and biological *** purpose of this study is to extend our developed ensemble decision approach to distinguish multiple heterogeneous phenotypes and to elucidate the underlying molecular bridges that intertwine the *** work identifies the significant molecular mechanisms (disease-relevant genes and functions) that underpin the complex molecular mechanisms for distinction between multiple phenotypes. Feature genes and hierarchical gene cores identified by our method have achieved high accuracy in the classification of multiple pheno- *** results show that the proposed analysis strategy is feasible and powerful in the classification of biological subtypes and in the explanation of the molecular connections between clinical *** interpretations with Gene Ontology revealed concerted genetic pathways for some lymphoma subtypes.

关键词： Ensemble decision approach Molecular mechanisms Lymphoma Microarray

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硫化镉的改性方法及其在光催化反应中的应用

太阳能学报 2008年第9期29卷 1117-1123页

作者：白雪峰樊慧娟王鹏哈尔滨工业大学市政环境工程学院哈尔滨150090 黑龙江省石油化学研究院哈尔滨150040

综述了水热法、微乳法和微波辐射法等CdS的制备方法以及CdS负载贵金属、CdS/TiO_2.合、CdS/ZnS复合、CdS嵌入层状化合物、负载型CdS等改性方法,并对改性后CdS在光催化中的应用效果进行介绍。

关键词：硫化镉(cas) 光催化改性方法

New Solution to Surface Temperature of Casting Slab Measurement Based on Preceded Reflector and Multi-Wavelength

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Journal of Iron and Steel Research International 2012年第8期19卷 12-16页

作者： LIU Jun1, MA Jiao-cheng2. YANG Feng3, XIAO Hui1, RAO Li-min1 (1. School of Nuclear engineering and technology, East{2. institute of technology, Fuzhou 344000, Jiangxi,{2. 2. School of Mechanical engineering and Automation, Northeastern University, Shenyang 110004, Liaoning,{2. 3. School of Civil and environmental engineering, East{2. institute of technology, Fuzhou 344000, Jiangxi,{2.) [a] School of Nuclear engineering and technology East China Institute of Technology Fuzhou 344000 Jiangxi China [b] School of Mechanical engineering and Automation Northeastern University Shenyang 110004 Liaoning China [c] School of Civil and environmental engineering East China Institute of Technology Fuzhou 344000 Jiangxi China

The surface temperature of casting slab is an important parameter in the metallurgy field. Because the surface emissivity is uncertain and also unknown, it is difficult to measure the slab surface temperature accurately. A method based on preceded reflector and multi-wavelength was put forward to deal with the difficulty in surface temperature measurement of casting slab. On the premise of preceded reflector and non-preceded reflector, the method establishes the radiation energy equations and works out the emissivity and temperature in the equations. Also, the multilayer modeling of casting slab surface and multiple reflection-absorption process modeling were built by Monte Carlo method. The temperature measuring method had been applied in the continuous casting field. In order to verify the measured result, the thermal imaging method was adopted when the slab surface emissivity was set by repeated tests. Finally, the measured and verified temperature curves keep a same tendency and the error of the values is lower than 5℃. The comparison result shows that the method can measure temperature accurately.

关键词： casting slab emissivity surface temperature preceded reflector multi-wavelength