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Scale effects on nonlocal buckling analysis of bilayer composite plates under non-uniform uniaxial loads

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Applied Mathematics and Mechanics(English Edition) 2015年第1期36卷 1-10页

作者： Xiang-wu PENG xing-ming GUO Liang LIU Bing-jie wu Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai University

Scale effects are studied on the buckling behavior of bilayer composite plates under non-uniform uniaxial compression via the nonlocal theory. Each isotropic plate is composed of a material that is different from others, and the adhesive between the plates is modeled as the Winkler elastic medium. According to the symmetry, effects of the Winkler non-dimensional parameter, the thickness ratio, the ratio of Young＇s moduli, and the aspect ratio are also considered on the buckling problem of bilayer plates, where only the top plate is under the uniaxial compression. Numerical examples show that the Winkler elastic coefficient, the thickness ratio, and the ratio of Young＇s moduli play decisive roles in the buckling behavior. Nonlocal effect is significant when the high-order buckling mode occurs or the aspect ratio is small.

关键词： buckling bilayer composite plates Winkler elastic medium nonlocal scale effect

Demixing microwave signals using system-on-chip photonic processor

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Light(Science & Applications) 2024年第3期13卷 399-401页

作者： Sheng Gao Chu wu xing Lin Department of Electronic Engineering Tsinghua University100084 BeijingChina Beijing National Research Center for Information Science and Technology Tsinghua University100084 BeijingChina

The integrated photonic processor,co-packaged with electronic peripherals,is proposed for blind source separation of microwave signals,which separates signal-of-interest from dynamic interference with real-time adapta... 详细信息

关键词： processor microwave mixing

Investigation into Experimental Conditions and Factors for Cyclohexane Oxidation with VO（acac）2

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Chemical Research in Chinese Universities 2014年第6期30卷 991-996页

作者： MA Xitong xing Na wu Qiong XU Liting xing Yongheng College of Chemistry and Chemical Engineering Liaoning Normal University Dalian 116029 P. R. China

The catalytic activity of VO（acac）2 for the cyclohexane（Cy） oxidation was studied. The effects of various parameters, such as the amounts of H202, HNO3, H20 and Cy were investigated. The highest total turnover num- ber（TON） is 234, which can be increased to 353, 342 and 403, respectively with the adding of o-phthalic, m-phthalic or p-phthalic acid. A reaction mechanism was also supposed primarily.

关键词： VO(acac)2 Cyclohexane oxidation Mechanism Phthalic acid Additive

The Performance Characteristics of a Nano-thermoelectric Refrigerator Driven by an External Stochastic Force

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Chinese Physics Letters 2013年第5期30卷 135-139页

作者： WANG Hao wu Guo-xing Tianhua College Shanghai Normal UniversityShanghai 201815

We describe a single level quantum dot driven by an external stochastic force which works as a nano-thermoelectric refrigerator. Based on the model, expressions for the cooling rate, power input, and coefficient of performance (COP) are derived. The effects of the energy level and energy space on the refrigerator are revealed. The optimal performance characteristics are analyzed by numerical calculation. Furthermore, the practical operating regions of the refrigerator are determined.

关键词： refrigerator calculation stochastic

Equation of Motion of a Mass Point in Gravitational Field and Classical Tests of Gauge Theory of Gravity

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Communications in Theoretical Physics 2007年第3期47卷 503-511页

作者： wu Ning ZHANG da-Hua Institute of High Energy Physics P.O. Box 918-1 Beijing 100039 China

A systematic method is developed to studY the classical motion of a mass point in gravitational gauge field. First, by using Mathematica, a spherical symmetric solution of the field equation of gravitational gauge field is obtained, which is just the traditional Schwarzschild solution. Combining the principle of gauge covariance and Newton＇s second law of motion, the equation of motion of a mass point in gravitational field is deduced. Based on the spherical symmetric solution of the field equation and the equation of motion of a mass point in gravitational field, we can discuss classical tests of gauge theory of gravity, including the deflection of light by the sun, the precession of the perihelia of the orbits of the inner planets and the time delay of radar echoes passing the sun. It is found that the theoretical predictions of these classical tests given by gauge theory of gravity are completely the same as those given by general relativity.

关键词： classical tests of gauge theory of gravity gauge theory of gravity classical solution of field equation Newton's second law of motion

Scattering of Solitons of Modified KdV Equation with Self-consistent Sources

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Communications in Theoretical Physics 2008年第4期49卷 809-814页

作者： ZHANG da-Jun wu Hua Department of Mathematics Shanghai University Shanghai 200444 China

This paper investigates in detail the dynamics of the modified KdV equation with self-consistent sources, including characteristics of one-soliton, scattering conditions and phase shifts of two solitons, degenerate ca... 详细信息

关键词： modified kdV equation with self-consistent source soliton scattering

Bioaccumulation of cadmium bound to humic acid by the bivalve Meretrix meretirx Linnaeus from solute and particulate pathways

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Journal of Environmental Sciences 2010年第2期22卷 198-203页

作者： xing wu Yongfeng Jia Huijie Zhu He Wang Key Laboratory of Pollution Ecology and Environmental Engineering lnstimte of Applied Ecology Chinese Academy of Sciences Shengyang 110016 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

Humic acid is an important pool of heavy metals in sediments. Generally, the presence of refractory humic matter in aquatic systems would decrease the bioavailability of Cd and hence control the bioaccumulation of Cd in benthic animals. In the present work, we applied a suspending system to determine the relative importance of particulate and dissolved fractions of humic acid as Cd sources for the bivalve Meretrix meretrix and to investigate the difference of bioaccumulation characteristics of Cd adsorbed on different fractions of humic acid. The results showed *** bioaccumulation characteristics of Cd from particulate and dissolved fractions of humic acid were apparently different due to biological responses of the clam to the particulates. At Cd concentration of 140 mg/kg, the accumulation of Cd from Cd associated with humic acid mixtures was mainly attributed to the dissolved fractions of humic acid. Compared to particulate fractions, Cd associated with the dissolved fractions of humic acid may be more bioavailable.

关键词： humic acid bioaccumulation cadmium Meretrix meretrix Linnaeus

A Sequential Converted Measurement Kalman Filter with Doppler Measurements in ECEF Coordinate System

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Chinese Journal of Electronics 2016年第1期25卷 139-145页

作者： wu Weihua JIANG Jing FENG Xun QIN xing Air Force Early Warning Academy

When there is the correlation between Doppler and slant range, previous literatures have presented some sequential filter algorithms. However, they are only applied to simplified fixed radar’ s local coordinate system. As a result, a Sequential converted measurement Kalman filter(SCMKF) with Doppler measurements based on the Earth centered earth fixed(ECEF) coordinate system applicable to a moving airborne platform which has time varying attitude is proposed. Firstly, the correlated Doppler and range are decorrelated using the Cholesky factorization, then the converted position measurements are obtained by a series of coordinate transformation with unchanged range component and other observations, such as azimuth and elevation angles; the corresponding error covariances are derived which are used to the Converted measurement Kalman filter(CMKF).Finally the sequential filter is implemented for changed pseudo-Doppler measurements. The proposed method is validated through Monte Carlo test compared with the performance of CMKF with just converted position measurements and traditional SCMKF with Doppler which ignores the correlation between Doppler and range noises,and the conclusion is obtained that utilizing Doppler information correctly can improve tracking performance, nevertheless, the improvement gain of filter accuracy is limited,which can provide some references for engineering application.

关键词： Target tracking Sequential filter Range rate Pseudo-Doppler measurements Earth centered earth fixed(ECEF) coordinate system Converted measurement Kalman filter(CMKF) Correlation coefficient

Controlled Cross-linking Strategy for Formation of Hydrogels,Microgels and Nanogels

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Chinese Journal of Polymer Science 2018年第1期36卷 8-17页

作者： Qing-Chen Cao xing Wang De-Cheng wu Beijing National Laboratory for Molecular Sciences State Key Laboratory of Polymer Physics&ChemistryInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Hydrogels are a kind of unique cross-linking polymeric materials with three-dimensional networks. Various efforts have been devoted to manipulate the formation of functional hydrogels in situ and enrich the production of hydrogels, microgels and nanogels with improved modulation capacity. However, these methods always fail to tune the gel properties because of the difficulty in achieving the precise control of cross-linking extents once the gel formation is initiated. Therefore, the preparation of tailor-made hydrogels remains a great challenge. Herein, we summarize a controlled cross-linking strategy towards not only fabrication of hydrogels at nano-, micro-and macro-scales, but also achievement of controlled assembly of nanoparticles into multifunctional materials in macroscopic and microscopic scales. The strategy is conducted by controllably activating and terminating the disulfide reshuffling reactions of disulfide-linked core/shell materials with selective core/shell separation using system p H or UV triggers. So it provides a facile approach to producing hydrogels, hydrogel particles and nanoparticle aggregates with tunable structures and properties, opening up the design possibility, flexibility and complexity of hydrogels, microgels/nanogels and nanoparticle aggregates from nanoscopic components to macroscopic objects.

关键词： Thiol-disulfide exchange Controlled cross-linking Hybrid hydrogels Hydrogel particles Biodegradation