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Preparation and characterization of sponge-like composites by cross-linking hyaluronic acid and carboxymethylcellulose sodium with adipic dihydrazide

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Preparation and characterization of sponge-like composites b...

Probability parametric imaging with DCE-MRI data to identify prostate cancer in the peripheral zone

第三届全国化学工程与生物化工年会

作者： Long Liu , Dengru Liu, Guocheng Du, Jian Chen school of biotechnology, southern yangtze university, {3., 2.4.36, china Key Laboratory of Industrial biotechnology, Ministry of Education, southern yangtze university, {3., 2.4.36, china

＜正＞In this study, sponge-like composites were prepared by cross-linking different amounts of hyaluronic acid （HA） and carboxymethylcellulose sodium （CMC-Na）. Adipic dihydrazide （ADH） was employed as the cross-linker and water-soluble 1-ethyl-3.[3.（dimethylaminopropyl）] carbodiimide （EDC） as the carboxyl-activating agent. Fourier-Transform Infrared （FT-IR） analysis was performed to characterize the expected amide linkages in the cross-linked composites, and the scanning electron microscopic （SEM） analysis was carried out to view their microstructures. Furthermore, the physico-chemical properties, such as swelling property, thermostability, the resistance to hyaluronidase （HAse） degradation and the antioxidant abilities towards hydroxyl free radical （OH）, were characterized. The FT-IR spectra showed the amide peak at 1476.11 cm-1, indicating the cross-linking between HA and CMC-Na by ADH. Scanning electron microscopic （SEM） views demonstrated that the microstructures of the composites were dependent on HA content in the composites. The equilibrium swelling ratio was about 20, indicating the excellent water-uptake abilities of the composites. The HA-CMCNa composites showed a thermal stability up to 23.℃. When exposed to PBS solution containing HAse （100 U/ml）, all of the composites could be degraded quickly in 15 h. But if the concentration of ADH and EDC in the cross-linking reaction system was increased up to 10 mmol/L respectively, the degradation process would last for 60 h. The prepared composites possessed great antioxidant abilities against ·OH and the ability to scavenge ·OH depended on the composition. All these results showed that the prepared HA-CMCNa composites were a kind of novel HA derivatives and have great potentials in biomedical application.

关键词： Hyaluronic acid (HA) Carboxymethylcellulose sodium (CMCNa) cross-linking

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Progress in Natural Science:Materials International 2006年第9期16卷 948-953页

作者： HUANG Xinrui, WANG Qiang, XU Yufeng, WANG Xiaoying and BAO Shanglian ( The Key Laboratory of Medical Physics and Engineering, Peking university, Beijing 100871, china The Medical school of Peking university, Beijing 100083. china 3. The First Hospital of Peking university, Beijing 10003., china) [a]The key Laboratory of Medical Physics and Engineering Peking University Beijing China [b]The Medical school of Peking university Beijing China [c]The First Hospital of Peking university Beijing China

To quantitatively analyze prostate dynamic contrast-enhanced magnetic resonance images (DCE-MRI), a retrospective study was carried out to construct a mathematical model to predict whether a lesion is cancerous or not. With known diagnosis of 52 re-gions-of-interest (10 malignant, 26 benign and 16 normal) in peripheral zone (PZ) of prostate from 18 patients undergoing needle biopsy and 8 normal volunteers, we combined feature parameters (k1, k2 and tp) from the linear-slope model with logistic regression to determine the statistical probability model. Prostate cancerous probability maps were derived using the model on each subject to examine the correlation between the model-based prediction and the known diagnosis. Compared the model prediction results of 52 regions-of-interest with the histopathologic results, the total agreement rate was 90.4 % ; the agreement rate was 60 % for the malignant and 97. 6 % for the nonmalignant. The diagnostic results only referencing the probability maps by two radiologists showed a high agreement in tissue characteristics and lesion location with the combining results from other diagnostic techniques such as PSA (prostate specific antigen) level and MRS (magnetic resonance spectroscopy) .

关键词： time-intensity curve prostate DCE-MRI logistic regression probability parametric image.

Zhang-Xuan thermal uplift and its genesis

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Progress in Natural Science:Materials International 2005年第8期15卷 725-732页

作者： SHAO Ji'an1*, NIU Shuyin2, ZHANG Lüqiao3.and LI Hongyang2(1. school of Earth and Space Sciences, Peking university, Beijing 100871, china 2. Shijiazhuang university of Economics, Shijiazhuang 05003., china 3. Geological Bureau of Inner Mongolia, Huhhot 010020, china) school of Earth and Space Sciences Peking University Beijing 100871 China. Shijiazhuang university of Economics Shijiazhuang 050031 China. Geological Bureau of Inner Mongolia Huhhot 010020 China

Based on the researches of the Mesozoic thermal evolution history, the deformed structures, and fission track analysis of the Zhangjiakou-Xuanhua area, we obtained the following knowledge: the area experienced in 140 Ma an underplating which is marked by emplacement of mantle derived magma; during 13.—110 Ma a series of eruptions and intrusions happened, and during 80—10 Ma a rising process occurred which is synchronous with the adjacent Taihang and Yanshan Mountains and was accompanied by a series of structures down slipping from the just formed Zhang-Xuan uplift toward its periphery. Combining the Zhang-Xuan thermal lift with the large detachment structure in Baoding depression of the North china Basin in the Late Mesozoic confirms that an even larger extensional tectonic background existed in North china during this period.

关键词： Zhang-Xuan area underplating thermal uplift fission track extensional structure.

Orientation-Singularity Representation and Orientation-Capability Computation of a Special Class of the Gough-Stewart Parallel Mechanisms Using Unit Quaternion

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Chinese Journal of Mechanical Engineering 2012年第6期25卷 1096-1104页

作者： LI Baokun1, 2, CAO Yi1, 3. *, ZHANG Qiuju1, and HUANG Zhen4 1 school of Mechanical Engineering, Jiangnan university, wuxi 214122,{3. 2 school of Mechanical Engineering, Anhui university of Science and Technology, Huainan 23.001,{3. 3.State Key Laboratory of Fluid Power Transmission and Control, Hangzhou 3.0027,{3. 4 Robotics Research Center, Yanshan university, Qinhuangdao 066004,{3. 1. school of Mechanical Engineering Jiangnan University Wuxi 214122 China 2. school of Mechanical Engineering Anhui University of Science and Technology Huainan 232001 China 3. State Key Laboratory of Fluid Power Transmission and Control Hangzhou 310027 China 4. Robotics Research Center Yanshan University Qinhuangdao 066004 China

Singular configuration seriously affects the performance of the Gough-Stewart parallel mechanism and has attracted many researchers’ attentions. However, most of existing topics often focus on the position-singularity of the mechanism for a constant-orientation, but few reports research the orientation-singularity for a given position. In order to investigate the orientation-singularity of the Gough-Stewart parallel mechanisms with two dissimilar semi-regular hexagonal platforms for a given position, after constructing the discrimination matrix of the singular configuration of the mechanism and computing the determinant of this matrix by using unit quaternion as the orientation parameters which can avoid the singularities in parameterization, a general symbolic expression representing the three-dimensional orientation-singularity locus for a given position is obtained and the three-dimensional view of the orientation-singularity locus is further described. The orientation-singularity-free void exists inside the orientation-singularity locus, but the shape of the orientation-singularity-free void is irregular and inconvenient for the design of the mechanism. The minimal inscribed sphere of the three-dimensional orientation-singularity locus namely the orientation-singularity-free ball is described. The radius of the ball orientation-capability is used as the measurement for the orientation-singularity-free void size. A new efficient algorithm is proposed for the computation of the orientation-capability. Finally, the influences of the geometry parameters and the different positions of the mechanism on the orientation-capability are discussed. A new method of the singularity analysis of the Gough-Stewart parallel mechanism is advanced based on the unit quaternion, and the research finds have important referential value for the configuration parameters optimization of this class of the parallel mechanisms with the goal of having the maximal singularity-free zone.

关键词： parallel mechanism unit quaternion orientation-singularity orientation-singularity-free void orientation-capability

Optimization of PCA-RBF Based Soft-Sensing Model

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Optimization of PCA-RBF Based Soft-Sensing Model

Preparation of CuO-CoO-MnO/SiO_2 Nanocomposite Aerogels as Catalyst Carriers and Their Application in the Synthesis of Diphenyl Carbonate

2006年国际电子、工程及科学领域的分布式计算和应用学术研讨会

作者： Zhang Hong school of Mechanical Engineering,southern yangtze {3. wuxi 214122,china Xu Wenbo school of information Engineering,southern yangtze {3. wuxi 214122,china Liu Fei Institute of Automation,southern yangtze {3. wuxi 214122,china

Principal Component Analysis(PCA) can effectively extract the characteristic information of data and eliminate co-linearity in *** Basis Function Neural-Network has the properties of fast learning and Global *** article puts forward a soft-sensing modeling method combining PCA and RBFNN,which selects the RBF centers by means of Data Clustering based on Quanta Particle Swarm *** transform function in Hidden Layer Unit is Gauss *** weight from hidden to output layer is also optimized by *** obtained soft-sensing is verified in measuring the oxygen content in CCR heating furnace.

关键词： soft-sensing PCA Neural-Network QSPO RBF

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Journal of Wuhan university of Technology(Materials Science) 2011年第4期26卷 595-599页

作者：赵越卿 school of Light Industry Hebei United University

CuO-CoO-MnO/SiO2 nanocomposite aerogels were prepared by using tetraethyl orthosilicate （TEOS） as Si source, and aqueous solution of Cu, Co and Mn acetates as transition metal sources via sol-gel process and supercritical drying （SCD） technique. The effect of synthesis conditions on gelation was investigated. Moreover, the composition of the CuO-CoO-MnO/SiO2 nanocomposite aerogels was characterized by electron dispersive spectroscopy （EDS） and X-ray photoelectron spectroscopy （XPS）, and the specific surface area of the nanocomposite aerogels was determined by the Brunauer-Emmett-Teller （BET） method. Diphenyl carbonate （DPC） as the product was analyzed by gas chromatography （GC）. The experimental results show that the range of optimal temperature for gelation is 3.-45 ℃, and the pH is 3.0-4.5. CuO-CoO-MnO/SiO2 nanocomposite aerogels are porous with a specific surface area of 3.4.9-700.6 m2/g. Compared to CO2 SCD, ethanol SCD is even favorable to the formation of aerogel with high specific surface area. The transition metals content in the nanocomposite aerogels can be controlled to be 0.71at%-13.77at%. With CuO-CoO-MnO/SiO2 nanocomposite aerogels as catalyst carrier, the yield of DPC is in direct proportion to the atomic fraction of transition metals in the nanocomposite aerogels, and it is up to 26.3. mass%, which is much higher than that via other porous carriers.

关键词： composite aerogel preparation catalyst carrier diphenyl carbonate

Electrical Breakdown Characteristic of Nanostructured W-Cu Contacts Materials

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Journal of Wuhan university of Technology(Materials Science) 2006年第4期21卷 32-35页

作者：王俊勃 school of Mechanical and Electrical Engineering Xi'an Polytechnic UniversityXi'an 710048 ChinaSchool of Science Xi'an Jiaotong University Xi'an 710049China

Nanostructured （ NS ）W-Cu composite powder was prepared by mechanical alloying （ MA ）, and nanostructared bulk of W-Cu contact material was fabricated by hot press sintering in an electrical vacuum furnace. The rnicrostructure, electric conductivity, hardness and break down voltage of NS W- Cu alloys were measured and compared to those of conventional W-Cu alloys prepared by powder metallurg＇y. The experimental results show that microstructural refinement and uniformity can improve the breakdown behavior and the electric arc stability of nanostructared W- Cu contacts materials. Also, the wanostructured W- Cu contact material shows the characteristic of spreading electric arcs, which is of benefit to electric arc erosion.

关键词： nanostructured materials W-Cu alloy electrical breakdown

Application of backflush and micro-flow techniques to the analysis of C5—C13.hydrocarbons in crude oils and its geochemical significance

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Progress in Natural Science:Materials International 2007年第11期17卷 1382-1387页

作者： Wang Peirong1,2, Zhao Hong2,3. Xu Guanjun1,4, Zhu Cuishan2,3. Xiao Tingrong4, Zhang Min2,3.and Zhang Bin1,4(1. Key Laboratory of Petroleum Geochemistry, china National Petroleum Corporation, Beijing 100083. china 2. Geochemistry Department of yangtze {3., Jingzhou 43.023. china 3. Key Laboratory of Exploration Technologies for Oil and Gas Resources, Ministry of Education, yangtze {3., Jingzhou 43.023. china 4. Petroleum Geology Central Laboratory, Research Institute of Petroleum Exploration and Development, Petrochina, Beijing 100083. china) Key Laboratory of Petroleum Geochemistry China National Petroleum Corporation Beijing 100083 China Geochemistry Department of yangtze university Jingzhou 434023 China Key Laboratory of Exploration Technologies for Oil and Gas Resources Ministry of Education Yangtze University Jingzhou 434023 China Petroleum Geology Central Laboratory Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

An Agilent 6890N GC equipped with both FID and Agilent 5975 MSD analyzer has been employed to analyze C5—C13.hydrocarbon fractions of crude oils. A technical combination of program temperature volatilizer injection, backflush and micro-flow controller afforded a fine separation of C5—C13.compounds on a PONA column with the heavy part of crude oils being cut off before entering the analytical column. Both GC-FID chromatogram and GC-MS mass chromatograms (MID and full scan) could be obtained at the same time. The retension time differences of nC6—nC13.alkanes between GC and TIC were in the range of 0.02—0.58 minutes. Totally 286 peaks have been assigned group compositions. Results on 8 typical oil samples from CNPC Key Laboratory Crude Oil Library showed that the characteristics of C6—C13.hydrocarbon group composition could be used in oil-oil correlation studies.

关键词： GC analysis GC/MS analysis backflush micro-flow controller light fraction in crude oil

Development and Application of High Performance X80 Line Pipe for the 2^(nd) West-East Gas Pipeline

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Journal of Iron and Steel Research International 2011年第S1期18卷 39-48页

作者： LI He-lin 1 , HUO Chun-yong 1 , JI Ling-kang 1, 2 , LI Yang 1, 3.(1. CNPC Tubular Goods Research Institute, Xi’an 710065, china 2. . school of Material Science and Engineering, Xi’an Jiaotong university, Xi’an 710049, china 3. school of Material Science and Engineering, university of Science and Technology Beijing, Beijing 100083. china) CNPC Tubular Goods Res Inst Xian 710065 Peoples R China Xi An Jiao Tong Univ Sch Mat Sci & Engn Xian 710049 Peoples R China Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

It is the development tendency of gas pipeline to improve strength of line pipe and transmission pressure, which is an important symbol of the progress of gas pipeline technology. The 2nd West-East Gas Pipeline (the 2 nd WEGP) is the largest-scale X80 high pressure gas pipeline project in the world. Through the joint development project by Pipeline Company, research institute, and steel company, a series of achievements of technology have been obtained, which makes it possible to apply pressure of 12 MPa and X80 LSAW and HSAW pipe for the 2 nd WEGP. Specifications of X80 steel and pipe have been issued based on API 5L. High performance X80 steel and pipe have been developed and meets the Specification. General design conception of applying HSAW pipe and LSAW pipe on gas transmission trunk line with large diameter and high pressure has been established. Failure control of the 2 nd WEGP has been carried out to avoid failure and reduce the lost which based on analysis of pipeline failure mode. In this paper, research and development of high performance X80 welded pipe, establishment of technical route of joint application of HSAW and LSAW steel pipe and key technology of failure control are emphatically discussed.

关键词： 2 nd WEGP acicular ferrite failure control arrest toughness strain-based design