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Smart Behavior of Carbon Fiber Reinforced Cement-based Composite

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Journal of Materials science & technology 2003年第3期19卷 239-242页

作者： Wu YAO, Bing CHEN Keru WUState Key Laboratory of Concrete Materials Research, tongji university, shanghai 200092, china Lab. of Concrete Mat. Res. Tongji Univ. Shanghai 200092 China

The electrical characteristics of cement-based material can be remarkably improved by the addition of short carbon fibers. Carbon fiber reinforced cement composite (CFRC) is an intrinsically smart material that can sense not only the stress and strain, but also the temperature. In this paper, variations of electrical resistivity with external applied load, and relation of thermoelectric force and temperature were investigated. Test results indicated that the electrical signal is related to the increase in the material volume resistivity during crack generation or propagation and the decrease in the resistivity during crack closure. Moreover, it was found that the fiber addition increased the linearity and reversibility of the Seebeck effect in the cement-based materials. The change of electrical characteristics reflects large amount of information of inner damage and temperature differential of composite, which can be used for stress-strain or thermal self-monitoring by embedding it in the concrete structures.

关键词： Carbon fiber Cement-based composite Smart material Seebeck effect

Gum mastic increases maspin expression in prostate cancer cells

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Acta Pharmacologica Sinica 2007年第4期28卷 567-572页

作者： Mei-lan HE~(2,3.6),Wei-wen CHEN~(2,6),Peng-ju ZHANG~2,An-li JIANG~2,Wei FAN~4,Hui-qing YUAN~2,Wen-wen LIU~2,Jian-yeZHANG~(2,5)~2Department of Biochemistry,Medical school,Shandong university,Ji-nan 250012,china ~3.nstitute of Cancer Research,{3. science andtechnology school,tongji university shanghai 200092,china ~4Gastric Intestine Department,Affiliated Qi-Lu Hospital,Shandong university,Ji-nan 250012,china Department of Biochemistry Medical School Shandong University Ji-nan China Institute of Cancer Research Life Science and Technology School Tongji University Shanghai China Gastric Intestine Department Affiliated Qi-Lu Hospital Shandong University Ji-nan China

Aim:To study whether gum mastic,a natural resin,can regulate maspin expres-sion in prostate cancer cells,and further investigate the mechanisms involved inthis regulatory ***:RT-PCR and Western blotting were used todetect maspin expression at the transcriptional and translational *** assay was used to investigate the effect of gum mastic on the maspin *** binding activity of negative androgen-responsive element (ARE) and posi-tive Spl element in the maspin promoter were studied by electrophoretic mobilityshift ***:Gum mastic induced maspin mRNA and protein expression,and the maspin promoter activity was enhanced with gum mastic ***,gum mastic inhibited the ARE binding activity and increased the Sp 1 bindingactivity in the maspin ***:Gum mastic enhances maspin pro-moter activity by suppressing ARE binding activity and enhancing Spl bindingactivity,and the increased activity in the maspin promoter finally leads to the up-regulation of both its mRNA and protein levels.

关键词： gum mastic maspin expression ARE binding activity Spl binding activity

Fractal Structure of the Core Loss Spectrum of Co-based Amorphous Soft Magnetic Alloy with Constant Permeability

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 54-56页

作者： Yiping Chen (Applied science school, university of science and technology Beijing, Beijing 100083. china) Applied science school University of Science and Technology Beijing Beijing 100083 China

In order to check the traditional core loss formula, the core loss spectrum P(f) of Co-based amorphous soft magnetic alloy with constant permeability has been studied. It is found that within a high frequency range from 10 kHz to 200 kHz and at Bm = 0. 1 T,the P(f) has the fractal structure P (f) = Po, and with the increasing of induced anisotropy energy Ku, the fractal dimension Dfrises, thus the total power loss at high frequency increases and the frequency characteristic of P(f) becomes worse.

关键词： amorphous soft magnetic alloy constant permeability core loss fractal

Application of the annexation principle to the study of thermodynamic properties of ternary metallic melts In-Pb-Ag and In-Bi-Sb

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Rare Metals 2002年第2期21卷 142-151页

作者： ZHANG JianMetallurgical Engineering school.university of science and {3. Beijing, Beijing 100083. china Metallurgical Engineering school University of Science and Technology Beijing 北京 100083

Based on the phase diagrams, measured activities an the annexationprinciple, the calculating models of mass action concentrations forin-Pb-Ag and In-Bi-Sb ternary metallic melts have been *** results of calculation both agree with practice, and obey the lawof mass action, showing that the models formulated can reflect thestructural reality of the corresponding melts and the annexationprinciple is applicable to the them.

关键词： activity mass action concnetration th annexation principle In-PB-Ag

A geometrical and physical nonlinear finite element model for spatial thin-walled beams with arbitrary section

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science china(Technological sciences) 2010年第3期53卷 829-838页

作者： YANG QingShan 1 &WANG XiaoFeng 2 1 school of Civil Engineering,Beijing Jiaotong university,Beijing 100044,china 2 College of Civil Engineering,{3. university,shanghai 200092,china 1. school of Civil Engineering Beijing Jiaotong University Beijing 100044 China2. College of Civil Engineering Tongji University Shanghai 200092 China

Based on the theories of Bernoulli-Euler beams and Vlasov's thin-walled members,a new geometrical and physical nonlinear beam element model is developed by applying an interior node in the element and independent interpolations on bending angles and warp,in which factors such as traverse shear deformation,torsional shear deformation and their coupling,coupling of flexure and torsion,and second shear stress are all ***,geometrical nonlinear strain in total Lagarange(TL) and the corresponding stiffness matrix are *** plastic model is applied to physical nonlinearity to comply with the yield rule of Von Mises and incremental relationship of *** stiffness matrix is derived by numerical integration on the basis of the finite segment *** show that the developed model is feasible in analysis of thin-walled structures with high accuracy.

关键词： Spatial beams thin-walled structures geometrical and physical nonlinearity finite element arbitrary section

Superconductivity of small metal grains

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science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 431-441页

作者： ZHENG Renrong1 CHEN Zhiqian2 & ZHU Shunquan1,3.1. Department of Physics, shanghai Normal university, shanghai 20023.,{3. 2. Department of Physics, Southwest Normal university, Chongqing 400715,{3. 3. Department of Computer and Electric technology, shanghai Business school, shanghai 201400,{3. 1. Department of Physics Shanghai Normal University 200234 Shanghai China 2. Department of Physics Southwest Normal University 400715 Chongqing China 3. Department of Computer and Electric technology Shanghai Business School 201400 Shanghai China

The formulas of the energy gap and superconducting critical temperature appropriate for systems with both odd and even number of electrons are derived; the bases of the derivations are BCS theory and energy level statistics. Numerical results qualitatively agree with the experimental phenomena. i.e., the superconductivity of small metallic grains will first enhance then decrease to zero when the grain are getting smaller and smaller. The calculations indicate that the above phenomena happen in the metallic grains belonging to Gaussian Orthogonal Ensemble (GOE) and Gaussian Unitary ensemble (GUE) with zero spin; The superconductivity of small metallic grains in Gaussian Symplectic Ensemble (GSE) will monotonically decrease to zero with the decreasing of the grain size. The analyses suggest that the superconductivity enhancements come from pairing and the balance of the strengths between spin-orbital coupling and external magnetic field. In order to take the latter into account, it is necessary to include the level statistics given by Random Matrix Theory (RMT) in describing small metallic grains.

关键词： size effect, superconductivity enhancements, small metallic grains.

Mass spectrometry analysis of melanoma related O-glycans in sera

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science china Chemistry 2010年第4期53卷 807-811页

作者： BAI Chen1,4, WU Gang1 & ZHAO Liang2,3.1Department of life science, Fudan university, {3. 20043., china 2Department of Chemistry, Fudan university, {3. 20043., china 3.nstitutes of Biomedical sciences, Fudan university, {3. 20043., china 4Department of Food science, {3. Business school, {3. 20023., china 1. Department of life science Fudan University Shanghai 200433 China4. Department of Food Science Shanghai Business School Shanghai 200235 China2. Department of Chemistry Fudan University Shanghai 200433 China3. Institutes of Biomedical Sciences Fudan University Shanghai 200433 China

Glycomics comparison was carried out by screening melanoma serum biomarkers between C57 mice with and without B16 implanted. O-glycans were released from 10 μL sera by β-elimination, purified by Graphitized Carbon Cartridge Solid Phase Extraction (GCC-SPE) and analyzed by MALDI-QIT-TOF-MS. MS raw data were acquired and exported by Launchpad software. MATLAB was then applied for further data analysis. 10 Glycans were considered to have stable changes after B16 implantation and 5 of them were under structural analysis via MS/MS.

关键词： mass spectrometry glycomics melanoma biomarkers

Nonclassical Plane-crystallographic Groups and Their Applications IV

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International Journal of Minerals,Metallurgy and Materials 1998年第4期12卷 228-232页

作者： Lequan Min Xaodan zhang(Applied science school, school,{3. of science and technology Beijing, Beijing 100083.china) Applied science school University of Science and Technology Beijing Beijing 100083 China

Eight kinds of nonclasslcal periodic lattices with locally 8-fold rotational symmetries are *** can be described via nonclassical Planc-crystallographic groups. The periodic lattices may be interpreted bythe projections on the plane of the corresponding unit cells consisting of embedding polyhedrons, respectively. TheFourier-transform patterns of the Periodic lattices have striking approximate'8-fold rotational symmetries', some ofwhich are similar to those displaying in the electrton-diffraction patterns of so-called quasicrystals.

关键词： nonclasslcal crystallographic groups locoally 8-fold symmetry Fourier-transform patterns, quasicrystals

Wide area real time kinematic decimetre positioning with multiple carrier GNSS signals

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science china Earth sciences 2010年第5期53卷 731-740页

作者： FENG YanMing1 & LI BoFeng1,2 1 Faculty of science and technology, Queensland university of technology, GPO Box 243., QLD 4001, Australia 2 Department of Surveying and Geo-informatics Engineering, tongji university, shanghai 200092, china 1. Faculty of science and technology Queensland University of Technology GPO Box 2434 QLD 4001 Queensland Australia2. Department of Surveying and Geo-informatics Engineering Tongji University Shanghai 200092 China

This paper presents the technical basis for wide area real time decimetre positioning services using multiple carrier signals transmitted by future GNSS such as modernized GPS and Compass systems. The first step is to form two ionosphere-reduced extra-widelanes (EWL) that have the minimal total noise levels in cycles, considering the effects of the ionospheric and tropospheric delays, orbital error, and phase noise terms in various observational environments. The proposed three carrier ambiguity resolution approach can determine the integer ambiguities of the selected EWL signals with geometry-free and geometry- based estimations respectively over the distances of typically hundreds of kilometres. With two ambiguity-fixed EWL signals, the kinematic positioning solutions can be achieved in decimetre level accuracy. A semi-simulation method is employed to generate three frequency Compass data to demonstrate the above expected performance for decimetre positioning services. Both theoretical and experimental results have demonstrated the overall 3. root mean square accuracy of better than 15 cm obtained through with a phase smoothing process over 120 epochs. The dominating error factor in this positioning result is the residual tropospheric biases, which would become less correlated as the baselines grow beyond hundreds of kilometres. With respect to dual-frequency based precise point positioning and wide area differential positioning solutions, a major advantage of using the third frequency signals is the convergence time being shorten from tens of minutes to a few minutes. In addition, due to the instant ambiguity resolution capability, phase breaks or cycle slips no longer affect the continuity of the solutions. This reliable decimetre positioning capability introduces a significant improvement to safety-of-life, liability-critical and professional applications.

关键词： GNSS three carrier ambiguity resolution real time kinematic decimetre positioning