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An analytical approach to modeling stress-strain relationship of particle-reinforced metal matrix composites

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Rare Metals 2022年第11期41卷 3903-3910页

作者： Zhao-Bing Xiang Jun-Hui Nie Shao-Hua Wei Tao Zuo Jian-Zhong Fan National Engineering Technology research Center for Nonferrous Metals Composites General Research Institute for Nonferrous MetalsBeijing100088China

An analytical model was established to simulate the stress-strain curves of particle-reinforced metal matrix composites by the classical stress equilibrium equation and secant modulus method,where particle cracking and matrix tearing were taken into *** stress-strain curves of the composites predicted by the model fit the experimental curves very *** stressstrain relationship of the matrix affected by the particles is predicted exactly,and it is found that the yield stress of the matrix is influenced obviously by the particle *** yield strength of the composites is also predicted by the model,and the results fit the experimental data very well.

关键词： Strengthening mechanism Yield strength Particle fracture Matrix stress-strain curve

Temperature distribution in front of the liquid-solid interface in the undercooled pure melt influenced by a transverse far field flow

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Journal of University of Science and Technology Beijing 2007年第6期14卷 495-500页

作者： Mingwen Chen Zidong Wang Wei Yang Renji Sun Xinfeng Wang Applied Science School University of Science and Technology Beijing Beijing 100083 China Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China Department of Mathematics Linyi Normal University Linyi 276000 China Beijing Union University Beijing 100101 China

The directional solidification in the undercooled pure melt influenced by a transverse far field flow was studied by using the multiple scale method. The result shows that in the boundary layer near the liquid-solid interface, when affected by a transverse far field flow, the temperature distribution in the direction of crystal growth presents an oscillatory and decay front in the side of liquid phase. The crucial distinguishing feature of a temperature pattern due to the transverse convection is the additional periodic modulation of the pattern in the growth direction. The wave number and eigenvalue that satisfy the Mullins-Sekerka dispersion relation are suppressed by the transverse far field flow.

关键词： metal solidification crystal growth pure melt far field flow

Effect of ammonium sulfate and urea on PCDD/F formation from active carbon and possible mechanism of inhibition

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Journal of Environmental Sciences 2014年第11期26卷 2277-2282页

作者： Mi Yan Zhifu Qi Jie Yang Xiaodong Li Jianli Ren Zhang Xu Institute of Energy and Power Engineering Zhejiang University of Technology State Key laboratory of Clean Energy Utilization Zhejiang University

The effect of ammonium sulfate （（NH4）2SO4） and urea （CO（NH2）2） on polychlorinated dibenzo-p-dioxin and dibenzofuran （PCDD/F） formation from active carbon was investigated in this study. Both additives could significantly inhibit PCDD/F formation, and PCDD/F （TEQ） generation was reduced to 98.5% （98%） or 64.5% （77.2%） after 5% （NH4）2S04 or CO（NH2）2 was added into model ash, respectively. The inhibition efficiency of PCDDs was higher than the value of PCDFs, however, the reduction of PCDD/F yield was mainly from PCDFs decreasing. In addition, the solid-phase products were reduced more than the gas-phase compounds by inhibitors. By the measurement of chlorine emission in the phase of ion （Cl[Cl^-]） and molecule gas （Cl[Cl2]）, it was observed that both Cl[Cl^-] and Cl[Cl2] were reduced after inhibitors were added into ash. Cl[Cl2] was reduced to 51.0% by urea addition, which was supposed as one possible mechanism of PCDD/F inhibition.

关键词： Inhibition PCDD/Fs Ammonium sulfate Urea Chlorine emission

Impacts of algal blooms removal by chitosan-modified soils on zooplankton community in Taihu Lake,China

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Journal of Environmental Sciences 2010年第10期22卷 1500-1507页

作者： Jiajia Ni Yuhe Yu Weisong Feng Qingyun Yan Gang Pan Bo Yang Xiang Zhang Xuemei Li Key Laboratory of Biodiversity and Conservation of Aquatic Organisms Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China. Graduate School of the Chinese Academy of Sciences Beijing 100039 China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China

It is important to assess the effect on zooplankton when perform the environmental protection or restoration technology, especially removing algal blooms, because algae were the major primary producer in algal lakes. The influence on zooplankton community after half a year of algal blooms removed by chitosan-modified soils in Taihu Lake was assessed and the rationality of carrying out the process semiannually was evaluated in the present study. Morphological composition and genetic diversity of zooplankton community were investigated by microscope checkup and polymerase chain reaction-denatured gradient gel electrophoresis （PCR-DGGE）. A total of 44 zooplankton taxa （23 protozoa, 17 rotifers, 3 copepoda and 1 cladocera） were detected by microscope checkup, and a total of 91 bands （28 bands amplified by primers F1427-GC and R1616, 63 bands amplified by primers Fung-GC and NS1） were detected by PCR-DGGE. The results of cluster analysis or detrended correspondence analysis indicated that there was no considerable difference in morphological composition of zooplankton and DGGE profiles between experimental and control sites, and DGGE profiles could represent the biologic diversity. The study showed that zooplankton community could recover original condition after half year of algal blooms removed by chitosan-modified soils and it was acceptable to apply this process semiannually. In addition, the results revealed that PCR-DCJGE could be applied to investigate the impacts of the environmental protection or restoration engineering on zooplankton community diversity.

关键词： algal blooms Microcystis aeruginosa zooplankton community chitosan-modified soils Taihu Lake

2D phosphides heterostructures on titanium microfiltration membrane for enhanced ampere-level current density overall seawater splitting

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Nano research 2025年第1期18卷 249-259页

作者： Wenjing Dai Xin Wang Yulong Ma Sisi He Ming Chen Zhaohui Yin Shuheng Tian Maolin Wang Shixiang Yu Hang Zhang Yuanzhe Wang Hong Wang Jianxin Li Faming Gao Bowen Cheng Yun Wang Zhen Yin Ding Ma Tianjin Key Laboratory of Brine Chemical Engineering and Resource Eco-utilization College of Chemical Engineering and Materials ScienceTianjin University of Science and TechnologyTianjin 300457China State Key Laboratory of Biobased Fiber Manufacturing Technology Tianjin University of Science and TechnologyTianjin 300457China Haian Institute of High-Tech research Nanjing UniversityHaian 226600China Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China State Key Laboratory of Separation Membranes and Membrane Processes Separation Membrane Science and Technology International Joint Research CentreTiangong UniversityTianjin 300387China Centre for Catalysis and Clean Energy School of Environment and ScienceGold Coast CampusGriffith UniversitySouthportQueensland 4222Australia

The advancement of direct seawater electrolysis is a significant step towards sustainable hydrogen production,addressing the critical need for renewable energy sources and efficient resource ***,direct seawater electrolysis has to face several challenges posed by the corrosiveness of highly concentrated chloride and the competitive chlorine evolution reaction(ClER).To overcome these issues,we designed a novel NiP_(2)@CoP electrocatalyst on a porous titanium microfiltration(Ti MF)*** obtained bifunctional NiP_(2)@CoP catalyst outperforms the Pt/C and IrO_(2),as evidenced by its low overpotentials of 192 and 425 mV at a current density of 500 mA·cm^(-2) for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)in alkaline seawater(1 M KOH+0.5 M NaCl),***,only 231 and 569 mV overpotentials are required at the current density of 1500 mA·cm^(-2) towards HER and OER in alkaline seawater,*** importantly,no ClER was observed,demonstrating its excellent selectivity to *** selection of porous Ti MF membrane as an electrode substrate further enhances the performance by providing a robust structure that promotes the fast generation and release of gas *** promising outcomes obtained with NiP_(2)@CoP catalysts on Ti MF support,therefore,pave the way for the commercial viability of direct seawater electrolysis technologies at industrial-level current densities.

关键词： direct seawater electrolysis porous titanium microfiltration membrane phosphides heterostructures NiP_(2)@CoP electrocatalyst excellent selectivity to oxygen evolution reaction(OER)

Current Status of the Fabrication of Li_4SiO_4and Beryllium Pebbles for CN HCCB TBM in SWIP

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Plasma Science and Technology 2013年第3期15卷 291-294页

作者：冯勇进冯开明曹启祥张建利胡劲 Southwestern Institute of Physics Baoji Haibao Special Metal Materials Co.Ltd. Kunming University of Science and Technology

Tritium breeder and neutron multiplier as functional materials play an important role not only in ITER test blanket module （TBM） but also in fusion reactor. The paper describes the status of the fabrication of the two materials in Southwestern Institute of Physics （SWIP）. Li4SiO4 pebbles were fabricated by melt-spraying method. Most of the pebbles with the diazneter of 1.0 mm are well spherically shaped. The properties of the pebbles have been investigated. The results show that the pebbles produced by this method have a high density of 93% TD （theoretical density）. It was also found that the open/closed porosity will be decreased after thermal treatment, but the average crush load will be increased to 7 N. The rotating electrode process （REP） has been adopted to produce beryllium pebble for impurity control and mass production. The pebbles with the diameter of 1.0 mm were produced by REP. The beryllium pebbles produced by REP look almost perfectly spherical with a very smooth surface and a high density of 98% TD. The test results indicate that REP method has excellent prospects for the fabrication of beryllium pebbles and the attractiveness of their properties.

关键词： Li4SiO4 pebbles melt-spraying method beryllium pebbles REP

The high deposition of microcrystalline silicon thin film by very high frequency plasma enhanced chemical vapour deposition and the fabrication of solar cells

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Chinese Physics B 2008年第9期17卷 3464-3470页

作者：陈永生汪建华卢景霄郑文谷锦华杨仕娥郜小勇郭学军赵尚丽高哲 Institute of Plasma Physics Chinese Academy of Sciences Key Laboratory of Material Physics Department of PhysicsZhengzhou University Department of Materials Science and Engineering Wuhan Institute of Technology

This paper reports that the intrinsic microcrystalline silicon （μc-Si：H） films are prepared with plasma enhanced chemical vapour deposition from silane/hydrogen mixtures at 200℃ with the aim to increase the deposition rate. An increase of the deposition rate to 0.88 nm/s is obtained by using a plasma excitation frequency of 75 MHz. This increase is obtained by the combination of a higher deposition pressure, an increased silane concentration, and higher discharge powers. In addition, the transient behaviour, which can decrease the film crystallinity, could be prevented by filling the background gas with H2 prior to plasma ignition, and selecting proper discharging time after silane flow injection. Material prepared under these conditions at a deposition rate of 0.78nm/s maintains higher crystallinity and fine electronic properties. By H-plasma treatment before i-layer deposition, single junction μc-Si：H solar cells with 5.5% efficiency are fabricated.

关键词： chemical vapour deposition plasma deposition solar cells crystallinity

Josephson Effect in MgB_(2): Large I_(c)R_(N) Product and Superconducting Energy Gap

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Chinese Physics Letters 2001年第9期18卷 1254-1255页

作者： XUAN Yi LI Zhuang-Zhi TAO Hong-Jie REN Zhi-An CHE Guang-Can ZHAO Bai-Ru ZHAO Zhong-Xian National Laboratory for Superconductivity Institute of Physics and Center for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100080

We report on the observation of the Josephson effect on the newly discovered superconductor MgB_(2) with the breakjunction technique. Similar to conventional superconductors, the I-V curve can be fitted with the resistively shunted junction model including the noise effect, and a large characteristic voltage V_(c)= I_(c)R_(N) = 9.6meV was obtained. The energy gap determined by the Ambegaokar-Baratoff relation with the fitted Vc is very consistent with the Bardeen-Cooper-Schrieffer weak-coupling value. Our result implies that the superconductor MgB_(2) is a promising material for Josephson device applications.

关键词： technique. value. Josephson

Ore-forming material sources of the Baiyangping Cu-Co-Ag polymetallic deposit in the Lanping Basin,western Yunnan Province

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Chinese Journal Of Geochemistry 2008年第3期27卷 217-224页

作者： LI Zhiming LIU Jiajun ZHANG Changjiang Wuxi research Institute of Petroleum Geology RIPED SINOPEC Wuxi 214151 China China University ofGeosciences Beijing 100083 China

The ore-forming material sources of the Baiyangping copper-cobalt-silver polymetallic deposit have been studied in view of the S, Pb, C, O and H isotopic characteristics and the ratio of Co/Ni of cobaltite. The results showed that sulfur in metallic sulfides may have come from a mixed sulfur-source consisting of the sulfur-source from metamorphic rocks in the basin basement with basic volcanic rocks and the sulfur-source from basin sulfates; lead in the ores was provided by the sedimentary rocks and basement rocks; CO2 in ore-forming fluids was derived from thermolysis of altered and normal marine facies carbonates and decarboxylation of sedimentary organic matter respectively; the ore-forming fluids belong to the SO4-Cl-Na-Ca-type basin thermal brines derived from paleo-meteoric waters; cobalt in the deposit may also be derived from the metamorphic rocks in the basin basement with basic volcanic rocks.

关键词：矿石金属铜钴银沉淀