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Research on cracking mechanism of the thin shell mould in expendable pattern shell casting during pattern removal process

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China Foundry 2010年第3期7卷 230-235页

作者： Jiang Wenming Fan zitian liao Defeng zhao zhong State Key Laboratory of Material Processing and Die ＆ Mould Technology Huazhong University of Science and Technology Wuhan 430074 Hubei China

Aiming at the cracking phenomenon of the thin shell mould in the expendable pattern shell casting during the pattern removing process, some systemic researches are *** influence of the pattern removing method and temperature on the pattern removing were *** shell mould cracking mechanism was analyzed by using thermo-gravimetric analysis (TGA), and combining the temperature field and the volume change of the expanded polystyrene (EPS) foam pattern being *** results indicated that the shell mould was not easily cracked when the pattern removing process was carried out with the furnace being heated little by little because of the shell slowly shrinking with dehydration and shell strength gradually *** shell mould was soon destroyed when it was set directly into the furnace at above 400 oC because of the thin shell mould rapidly shrinking and the foam pattern ***, the shell mould had no cracking when it had been preheated for a long time even if the furnace temperature was above 400 oC and the shell was put into the furnace ***, when the shell mould was directly set into the furnace at lower temperatures, 250 to 300 ℃, the shell would shrink slowly and the foam pattern would stay at the maximum expansion stage temperature of 100 to 110 ℃ for a long time; and the shell mould would experience an expansion force from the foam pattern for a long *** expansion force is related to the pattern removing temperature, holding time, foam pattern thickness and ***, the foam pattern with higher density could make the shell crack.

关键词： expendable pattern shell casting pattern removing cracking shrinkage expansion force

Strong magnetoresistance modulation by the Ir-insertion in Ta/Ir/CoFeB trilayer

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Strong magnetoresistance modulation by the Ir-insertion in T...

A New Method for Fitting Current–Voltage Curves of Planar Heterojunction Perovskite Solar Cells

TFC'19第十五届全国薄膜技术学术研讨会

作者： R.Q.zhang L.Y.liao x.z.Chen H.Q.Wu F.Pan C.Song Key Laboratory of Advanced Materials (MOE) School of Materials Science and EngineeringTsinghua University Institute of Microelectronics Tsinghua University

The spin-orbit torque (SOT) switching of trilayers with two heavy metal layers on the same side of the ferromagnetic metallayer were studied, realizing tunable spin Hall angle,domain wall motion and Dzyaloshinskii-Mor...

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Nano-Micro Letters 2018年第1期10卷 45-52页

作者： Peizhe liao xiaojuan zhao Guolong Li Yan Shen Mingkui Wang Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology Ningxia University

Herein we propose a new equivalent circuit including double heterojunctions in series to simulate the current–voltage characteristic of P–I–N planar structure perovskite solar cells. This new method can theoretically solve the dilemma of the parameter diode ideal factor being larger than2 from an ideal single heterojunction equivalent circuit,which usually is in the range from 1 to 2. The diode ideal factor reflects PN junction quality, which influences the recombination at electron transport layer/perovskite and perovskite/hole transport layer interface. Based on the double PN junction equivalent circuit, we can also simulate the dark current–voltage curve for analyzing recombination current(Shockley–Read–Hall recombination) and diffusion current(including direct recombination), and thus carrier recombination and transportation characteristics. This new model offers an efficacious and simple method to investigate interfaces condition, film quality of perovskite absorbing layer and performance of transport layer, helping us furtherimprove the device efficiency and analyze the working mechanism.

关键词： Dark current Device simulation Junction property Perovskite Solar cell

Improving Refinery Profits via Fine Management of Hydrogen Networks

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China Petroleum Processing & Petrochemical Technology 2010年第2期12卷 57-62页

作者： liao zuwei zhang Yi Rong Gang Yang Yongrong State Key Laboratory of lndustrial Control Technology Zhejiang University Hangzhou 310027 State Key Laboratory of Chemical Engineering Zhejiang University

Hydrogen network management is important to refineries. Various systematic management techniques have been developed to improve the efficiency of refinery hydrogen networks. However, existing methods all treat the hydrogen network separately. The tradeoff between hydrogen network cost and oil processing network benefit has not been explored in the hydrogen network management yet. A novel sensitivity analysis scheme is presented to take oil processing network into consideration. Oil processing unit which is sensitive to both oil processing networks and hydrogen networks is identified first. Then, sensitivity analysis of the unit around the operating point of oil processing networks and hydrogen networks is carried out. Finally, the overall optimal operating condition is obtained. An example of a real Chinese refinery demonstrates the effectiveness of the proposed analysis method.

关键词： refinery oil processing networks hydrogen network sensitivity analysis

Catalytic combustion of ethyl acetate over CeMnO_x and CeMnzrO_x compounds synthesized by coprecipitation method

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Journal of Natural Gas Chemistry 2011年第6期20卷 623-628页

作者： xiaoshuang Li Jianli Wang Chuanwen liao Hongyan Cao Yaoqiang Chen Maochu Gong Key Laboratory of Green Chemistry ＆ Technology of Ministry of Education College of Chemistry Sichuan University Chengdu 610064 Sichuan China

Ce0.6Mn0.4O2 catalysts with different sources of manganese and Ce0.6-xzrxMn0.4O2 mixed oxide catalysts were prepared by coprecipitation method and were characterized by N2 adsorption-desorption,TPR,xRD,and xPS *** activities of the prepared catalysts for ethyl acetate combustion,and the effects of calcination temperature and space velocity on catalytic activity were *** results showed that partial replacement of Mn（NO3）2 with KMnO4 as sources of manganese could improve activities of ***0.45zr0.15Mn0.4O2 catalyst exhibited the best catalytic activity and high thermal stability,e.g.,T90 could be still below 210℃ even if space velocity was up to 20000h-1.

关键词： ethyl acetate catalytic combustion volatile organic compound CeMnzrOx catalysts

Effect of polyamine on seed germination of wheat under drought stress is related to changes in hormones and carbohydrates

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Journal of Integrative Agriculture 2016年第12期15卷 2759-2774页

作者： LIU Yang xU Hong WEN xiao-xia liao Yun-cheng College of Agronomy Northwest A&F University

Drought is a multifaceted stress condition that inhibits crop growth. Seed germination is one of the critical and sensitive stages of plants, and its process is inhibited or even entirely prevented by drought. Polyamines （PAs） are closely associ- ated with plant resistance to drought stress and seed germination. However, little is known about the effect of PA on the seed germination of wheat under drought stress. This study investigated the involvement of PAs in regulating wheat seed germination under drought stress. Six wheat genotypes differing in drought resistance were used, and endogenous PA levels were measured during seed germination under different water treatments. In addition, external PAwas used for seed soaking and the variation of hormones, total soluble sugar and starch were measured during the seed germination under different water treatments. These results indicated that the free spermidine （Spd） accumulation in seeds during the seed germination period favored wheat seed germination under drought stress; however, the free putrescine （Put） accumulation in seeds during the seed germination period may work against wheat seed germination under drought stress. In addition, seed soaking in Spd and spermine （Spm） significantly relieved the inhibition of seed germination by drought stress; howev- er, soaking seeds in Put had no significant effect on seed germination under drought. External Spd and Spm significantly increased the endogenous indole-3-acetic acid （IAA）, zeatin （z）＋zeatin riboside （zR）, abscisic acid （ABA）, and gibberellins （GA） contents in seeds and accelerated the seed starch degradation and increased the concentration of soluble sugars in seeds during seed germination. This may promote wheat seed germination under drought stress. In conclusion, free Spd and Put are key factors for regulating wheat seed germination under drought stress and the effects of Spd and Put on seed germination under drought notably related to hormones and starch metab

关键词： polyamine drought seed germination wheat abscisic acid starch

An effective framework for asynchronous incremental graph processing

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Frontiers of Computer Science 2019年第3期13卷 539-551页

作者： xinqiao LV Wei xIAO Yu zHANG xiaofei liao Hai JIN Qiangsheng HUA Service Computing Technology and System Lab Cluster and Grid Computing Lab School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

Although many graph processing systems have been proposed, graphs in the real-world are often dynamic. It is important to keep the results of graph computation up-todate. Incremental computation is demonstrated to be an efficient solution to update calculated results. Recently, many incremental graph processing systems have been proposed to handle dynamic graphs in an asynchronous way and are able to achieve better performance than those processed in a synchronous way. However, these solutions still suffer from sub-optimal convergence speed due to their slow propagation of important vertex state (important to convergence speed) and poor locality. In order to solve these problems, we propose a novel graph processing framework. It introduces a dynamic partition method to gather the important vertices for high locality, and then uses a priority-based scheduling algorithm to assign them with a higher priority for an effective processing order. By such means, it is able to reduce the number of updates and increase the locality, thereby reducing the convergence time. Experimental results show that our method reduces the number of updates by 30%, and reduces the total execution time by 35%, compared with state-of-the-art systems.

关键词： incremental computation graph processing iterative computation asynchronous convergence

Variability of the currents in the Luzon Strait during spring of 2002 obtained from observations and satellite geostrophic currents and spectral analyses

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Science China Earth Sciences 2009年第4期52卷 519-531页

作者： YUAN YaoChu liao GuangHong WANG HuiQun LOU RuYun CHEN Hong State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyState Oceanic AdministrationHangzhou 310012China

The structure and variability of the currents in the Luzon Strait during spring of 2002 are studied, based on the current measurements at the average position of the mooring station (20°49′57"N, 120°48′12"E) from March 17 to April 15, 2002, satellite geostrophic currents in the Luzon Strait, and the spectral analyses, using the maximum entropy method. The subtidal currents at the mooring station show de-creased amplitudes downward with an anti-cyclonic rotation, suggesting that the currents enter and exit the South China Sea in the upper and intermediate layers, respectively. The vertical structure of the currents in the Luzon Strait suggests strongly the sandwiched structure of the LST, even though the bottom part of the profile is not resolved by the observational grid. The spectral analyses show the following periods of significant spectral peaks: (1) the tidal currents variability in the vertical direction; (2) the period about 4-6 d for the two cases of frequency f >0 and f0; (3) The fluctuation in the period range is about 2-3 days for the two cases of f >0 and fzon Strait currents exhibit significant synoptical variability throughout the water column up to 800 m deep. Both direct current measurements and in situ hydrographic and satellite survey suggest no Kuroshio loop current in the Luzon Strait during the spring of 2002.

关键词： currents in the Luzon Strait tidal currents and synoptical variability satellite geostrophic currents sandwiched structure Kuroshio loop current

Enhanced thermal shock and oxidation resistance of Si_2BC_3N ceramics through MWCNTs incorporation

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Journal of Advanced Ceramics 2018年第3期7卷 276-288页

作者： Ning liao Dechang JIA zhihua YANG Yu zHOU Yawei LI Institute for Advanced Ceramics School of Materials Science and EngineeringHarbin Institute of Technology Key Laboratory of Advanced Structure-Function Integrated Materials and Green Manufacturing Technology Ministry of Industry and Information Technology State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology National–provincial Joint Engineering Research Center of High Temperature Materials and Lining Technology

Multi-walled carbon nanotubes(MWCNTs)reinforced Si_2BC_3N ceramics were prepared through mechanical alloying(MA)and following spark plasma sintering(SPS).The thermal shock resistance of Si_2BC_3N ceramics was evaluated comparatively through ice water quenching test and theoretical ***,the oxidation resistance of MWCNTs incorporated Si_2BC_3N ceramics was evaluated under high *** results show that the calculated parameters such as the critical thermal shock temperature(R)and the thermal stresses resistance(R_(st)),as well as the toughness(R"")are improved with addition of 1 vol%*** addition,the crack propagation resistance of 1 vol%MWCNTs incorporated Si_2BC_3N ceramics is obviously improved through generating more tortuous crack propagation paths attributing to the"crack bridging","pull-out",and"crack deflection"mechanisms of ***,the residual strengths of 1 vol%MWCNTs containing specimens remained the highest after the thermal shock ***,the present work also reveals that the oxidation resistance is more sensitive to relative density than MWCNTs addition.

关键词： Si2BC3N ceramics MWCNTs thermal shock resistance oxidation resistance