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A Universal Equipment for Biaxial Stretching of Polymer Films

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Chinese Journal of Polymer science 2015年第5期33卷 754-762页

作者： Ling-pu Meng Yuan-fei Lin Jia-li Xu Xiao-wei Chen Xue-yu Li Qian-lei Zhang Rui Zhang Nan Tian 李良彬 National Synchrotron Radiation Lab and College of nuclear science and Technology CAS Key Laboratory of Soft Matter ChemistryUniversity of Science and Technology of China

A biaxial stretching equipment was designed and constructed to enable fundamental studies of the relationship between film processing conditions and structures of oriented film products. With programmable drive motors and scissorlike mechanism, all stretching modes, including uniaxial stretching with constant and free width, simultaneous and sequential biaxial stretching, can be applied to a square-shaped sheet. Parameters related to film stretching manufacturing, such as temperature, draw ratio and stretching speed can be set independently to meet the requirement of different polymers. The force information during stretching is recorded by two miniature tension sensors in two directions independently, which can monitor the mechanical stimulus and stress response. Using this equipment, experiments are conducted to investigate the influence of stretching parameters on the structure of polypropylene films, which provides an effective method to tailor the processing conditions to obtain the films with desired properties.

关键词： Biaxial stretching Processing/structure relationship Dynamics of stretching

Interactions of oxidative radicals with N-phosphoryl dipeptide derivatives

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Chinese Journal of Chemistry 1999年第6期17卷 592-598,4页

作者：储高升陈家富张志成姚思德 Department of applied Chemistry University of Science and Technology of China Hefei Anhui 230026 China laboratory of Radiation Chemistry Chinese Academy of Sciences Shanghai Institute of Nuclear Research Shanghai 201800 China

The interactions of oxidative radicals (Br2?-, HO?etc.) with N-phosphoryl dipeptide derivatives (NDM-TrpOMe and NDT-MetOMe) have been investigated by using pulse radiolysis at different pH values. It has been found that Br2?- and HO? radicals oxidize the Met-site and Trp-site in the dipeptide derivatives via formation of the three-electron-bonded intermediate and indolyl radical simultaneously. Then the intramolecular electron transfer along the peptide backbone occurs. The rate constants of electron transfer, k, have been determined and the reaction mechanism has been deduced.

关键词： N-Phosphoryl dipeptide oxidation electron transfer pulse radiolysis

Design of a new kind of chemical experiment container with virtual reality fusion

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Virtual Reality & Intelligent Hardware 2023年第4期5卷 317-337页

作者： Lurong YANG Zhiquan FENG Junhong MENG Department of Information science and Engineering University of JinanJinan 250022China Shandong Provincial Key laboratory of Network Based Intelligent Computing Jinan 250022China

Background At present,the teaching of experiments in primary and secondary schools is affected by cost and security *** research on virtual experiment platforms has alleviated these ***,the lack of real experimental equipment and use of a single channel to understand user intentions weaken these platforms operationally and degrade the naturalness of *** To solve these problems,we propose an intelligent experimental container structure and a situational awareness algorithm,both of which are verified and applied to a chemical experiment involving virtual-real ***,the acquired images are denoised in the visual channel using the maximum diffuse reflection chroma to remove ***,container situational awareness is realized by segmenting the image liquid level and establishing a relation-fitting ***,strategies for constructing complete behaviors and making priority comparisons among behaviors are adopted for information complementarity and independence,respectively.A multichannel intentional understanding model and an inter-active paradigm that integrates vision,hearing,and touch are *** The experimental results show that the accuracy of the intelligent container situation awareness proposed in this paper reaches 99%,and the accuracy of the proposed intention understanding algorithm reaches 94.7%.The test shows that the intelligent experimental system based on the new interaction paradigm also has better performance and a more realistic sense of operation experience in terms of experimental *** The results indicate that the proposed experimental container and algorithm can achieve a natural level of human-computer interaction in a virtual chemical experiment platform,enhance the user′s sense of operation,and achieve high levels of user satisfaction.

关键词： Multichannel intent fusion understanding Virtual-real fusion Natural interaction Remove image highlights Nonlinear curve fitting

Improvement in the calculation of anti-Stokes energy transfer and experimental justification based on Er_(0.01)Yb_xY_(1 0.01 x)VO_4 crystal

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Chinese Physics B 2010年第9期19卷 604-611页

作者：陈晓波卢建张蕴芝徐小灵冯宝华王策 Gregory J. Salamo 杨国建 nuclear science&Technology School and Analytical Testing Center Applied Optics Beijing Area Major LaboratoryBeijing Normal University Institute of Physics Chinese Academy of Sciences University Arkansas Department of PhysicsFayetteville

The improvement on the calculation of anti-Stokes energy transfer rate is studied in the present work. The additional proportion coefficient between Stokes and anti-Stokes light intensities of quantum Raman scattering theory as compared with the classical Raman theory is introduced to successfully describe the anti-Stokes energy transfer. The theoretical formula for the improvement on the calculation of anti-Stokes energy transfer rate is derived for the first time in this study. The correctness of introducing coefficient exp{△E/kT} from well-known Raman scatter theory is demonstrated also. Moreover, the experimental lifetime measurement in Er0.01YbxY1-0.01-xVO4 crystal is performed to justify the validity of our important improvement in the original phonon-assisted energy transfer theory for the first time.

关键词： improvement of anti-Stokes energy transfer Raman scattering quantum and classical theory Er0.01YbxY1-0.01-xVO4 crystal

Oxidizing mechanism of podophyllotoxin and its derivatives by sodium persulfate

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science China Chemistry 1996年第4期39卷 425-432页

作者：汪世龙姚思德张志成张曼维姜岳 Department of applied Chemistry University of Science and Technology of China Hefei 230026 China laboratory of Radiation Chemistry Shanghai Institute of Nuclear Research Chinese Academy of Sciences Shanghai 201800 China.

The oxidizing mechanism of podophyllotoxin and its derivatives by sodium persulfate has been studied by laser flash photolysis and pulse radiolysis. The formation and decay processes of transient species of podophyllotoxin and its derivatives have been observed, and a series of rate constants for the formation and decay of transient species have been determined. It has been found that there is a light (UV) sensitive group on the C-4 of podophyllotoxin and two light (UV) sensitive groups on the C-4 and C-4’ of 4’-demethylepipodophyllotoxin.

关键词： podophyllotoxin laser flash photolysis pulse radiolysis sodium persulfate.

CONSTRAINED RATIONAL CUBIC SPLINE AND ITS APPLICATION

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Journal of Computational Mathematics 2001年第2期19卷 143-150页

作者： Qi Duan Huan-ling Zhang Xiang Lai Nan Xie Fu-hua(Frank)Cheng Department of applied Mathematics Shandong University of TechnologyJinan 250061China Department of Computer science University of KentuckyLexingtonKY 40506USA

In this paper, a kind of rational cubic interpolation function with linear denominator is constructed. The constrained interpolation with constraint on shape of the interpolating curves and on the second-order derivative of the interpolating function is studied by using this interpolation, and as the consequent result, the convex interpolation conditions have been derived.

关键词： rational spline constrained design constrained interpolation convex interpolation shape control

Damping of Particle-Reinforced Composites Due to Interfacial Sliding

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Acta Mechanica Solida Sinica 2018年第5期31卷 623-634页

作者： Linghui He Renhuai Liu CAS Key laboratory of Mechanical Behavior and Design of Materials University of Science and Technology of China Hefei 230026 China MOE Key Lab of Disaster and Control in Engineering Institute of Applied Mechanics Jinan University Guangzhou 510632 China

Mechanical damping of composites reinforced by randomly distributed particles due to interfacial sliding is analyzed. The matrix is elastically isotropic, and the particles are assumed rigid and of identical radii. An auxiliary problem is solved at first for the steady-state response of an infinite matrix containing a single inclusion to a harmonic external load. The result is then used to derive the explicit expression of the specific damping capability of the composite by using Mori-Tanaka＇s mean-field method. Numerical results are given and discussed in detail. It is concluded that the overall damping of the composite depends on several factors, including volume fraction of particles, Poisson＇s ratio of matrix and a dimensionless parameter that incorporates the combined effects of particle size, matrix stiffness, interracial viscosity and vibration frequency. The result is expected to be helpful in tailoring the damping performance of particle-reinforced composites.

关键词： Particle-reinforced composite Damping Interracial sliding

Improvements in methodology to determine feedback reactivity coefficients

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nuclear science and Techniques 2019年第4期30卷 91-104页

作者： Faisal Qayyum Muhammad Rizwan Ali Awais Zahur R.Khan Department of nuclear Engineering Pakistan Institute of Engineering and Applied Sciences (PIEAS) Department of nuclear Engineering Pakistan Institute of Engineering and Applied Sciences(PIEAS)

The reactivity of a nuclear reactor is the most important safety and operating parameter. Due to short reactor period, the Light Water Reactor(LWR) designs require the compensations of rapid unfavorable reactivity increases. The increase in fuel or moderator temperature leads to compensate the reactivity jumps as inherent safety characteristics. The safe and reliable reactor operation requires the accurate assessment of these reactivity changes. This paper highlights the improvements in the methodology to determine the feedback reactivity changes in IAEA MTR benchmark. This method incorporates the reactivity effects of fuel temperature in moderator regions and vice versa. For this purpose, a detailed 3D model of the IAEA 10 MW MTR benchmark reactor is developed employing OpenMC computer code. OpenMC is a probabilistic computer code for neutronic calculations. This work uses temperature-dependent JEFF 3.2 cross-sectional library. The model is validated against the reference results of eigenvalues for control rods(inserted and in fully withdrawn position), control rod reactivity worth, averaged thermal flux in the central flux trap, and power fraction for each fuel element at beginning of life. The validated model is applied to simulate the feedback reactivity coefficients against the conventional reference results. In order to improve the methodology, the effect of the moderator temperature and void on fuel is incorporated to obtain a more realistic value of the fuel temperature ***, the moderator temperature coefficient and void coefficient are improved by incorporating the coupling effects of fuel temperature on moderator. This methodology can be applied to improve the LWR designs.

关键词： OpenMC MTR benchmark Reactivity feedback coefficients Fuel temperature coefficient Moderator temperature coefficient Void coefficient of reactivity

Liquid metal assisted regulation of macro-/micro-structures and mechanical properties of nanoporous copper

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science China(Technological sciences) 2021年第10期64卷 2229-2236页

作者： ZHANG Ying BAI QingGuo YANG WanFeng ZHANG ZhongHua Key laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJinan 250061China School of applied Physics and Materials Wuyi UniversityJiangmen 529020China

Nanoporous metals have received significant attention as a new class of structural and functional ***,the macroscopic brittle fracture under the tensile test is an impediment to their practical ***,it is of central importance to develop nanoporous materials with low cost and high tensile ***,a nanoporous Cu film supported on a pure Cu substrate(NPC@Cu)was fabricated by utilizing a liquid Ga assisted alloying-dealloying strategy,and the thickness of NPC film can be precisely regulated by changing the mass loading of liquid ***-situ X-ray diffraction was performed to further explore the alloying/dealloying *** NPC@Cu films show good tensile mechanical properties with a minimum elongation of 13.5%,which can be attributed to the good interface bonding and certain modulus matching between the nanoporous Cu layer and the Cu *** findings demonstrate that the design of film-substrate structure provides a feasible strategy for enhancing the mechanical properties of nanoporous metals.

关键词： nanoporous metals dealloying mechanical properties in-situ X-ray diffraction structural regulation