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Acta Metallurgica Sinica(English Letters) 2018年第12期31卷 1311-1316页

作者： Qiang li Yun-Bo Zhong Chu-Xiong Sun Huai Wang Tian-Xiang Zheng Wei-li Ren Zhong-ming Ren State Key Laboratory of Advanced Special Steels Shanghai University

The voltage was recorded to investigate the influence of the static magnetic field on droplet evolution during the mag-netically controlled electroslag remelting （MC-ESR） process. MC-ESR experiments were carried out under differentremelting current, and transverse static magnetic fields （TSMF） of 85 mT, 130 mT and 160 mT were *** work was performed to obtain the quantitative data of the droplets. The ASPEX Explorer was utilized toinvestigate the inclusions evolution of GCr15 ingots. The number of the droplets was 31 in 20 s during the traditional ESRprocess and reached 50 and 51 under the MC-ESR process with the TSMF of 85 mT and 130 mT, respectively. Whencompared the traditional ESR process with the MC-ESR process, the inclusions amount reduced 67%.

关键词： Electroslag remelting Static magnetic field Droplet transient Inclusions evolution Electromagnetic vibration effect

Sub-solvus Cellular Recrystallization and P Phase Formation in a Single-Crystal Superalloy Containing Re

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Acta Metallurgica Sinica(English Letters) 2015年第1期28卷 72-76页

作者： Long-Chao Zhuo ming Huang Ji-Chun Xiong Jia-Rong li Jing Zhu The State Key Laboratory of New Ceramics and Fine Processing Laboratory of Advanced Materials (MOE) School of Materials Science and Engineering National Center for Electron Microscopy in Beijing Tsinghua University Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical Materials

Sub-solvus recrystallization behavior of a second-generation single-crystal superalloy has been studied by transmission electron microcopy and scanning transmission electron microcopy. Surface local stress facilitated cellular recrystallization accompanied with formation of twin structure and TCP phase of P during annealing at sub-solvus temperature of 1,100 °C. The precipitation of P phase is considered to be attributed to the coarsening of c0 phase in the recrystallized aggregates which lower the activation energy for atomic migration.

关键词： Nickel-based single-crystal superalloys Interfaces Recrystallization Twin boundary STEM

Polyoxygenated dihydropyrano[2,3-c]pyrrole-4,5-dione derivatives from the marine mangrove-derived endophytic fungus Penicillium brocae MA-231 and their antimicrobial activity

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Chinese Chemical Letters 2015年第5期26卷 610-612页

作者： ling-Hong Meng Xiao-ming li Yang liu Bin-Gui Wang Key Laboratory of Experimental Marine Biology Institute of OceanologyChinese Academy of Sciences University of the Chinese Academy of Sciences

A new polyoxygenated dihydropyrano[2,3-c]pyrrole-4,5-dione derivative, pyranonigrin F （1）, together with a related known compound, pyranonigrin A （2）, were isolated and identified from Penicillium brocae MA-231, an endophytic fungus obtained from the fresh tissue of the marine mangrove plant Avicennia marina. The structures of these metabolites were determined based on comprehensive spectral interpretation and the absolute configuration of compound 1 was established by X-ray crystallographic analysis. Compounds 1 and 2 showed potent activity against a broad spectrum of human-, aqua-, and plant-pathogens.

关键词： Mangrove-derived fungus PeniciUium brocae Secondary metabolites Pyranonigrin F Antibacterial activity

Rapid detection of intestinal pathogens in fecal samples by an improved reverse dot blot method

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World Journal of Gastroenterology 2009年第20期15卷 2537-2542页

作者： Jian-ming Xing Su Zhang Ying Du Dan Bi li-Hui Yao Huzhou Maternity and Child Care Hospital Huzhou 313000 Zheiiang Province China

AIM:To develop a new, rapid and accurate reverse dot blot(RDB) method for the detection of intestinal pathogens in fecal ***:The 12 intestinal pathogens tested were Salmonella spp., Brucella spp., Escherichia coli O157:H7, Clostridium botulinum , Bacillus cereus , Clostridium perfringens , Vibrio parahaemolyticus , Shigella spp., Yersinia enterocolitica, Vibrio cholerae, listeria monocytogenes and Staphylococcus *** two universal primers were designed to amplify two variable regions of bacterial 16S and 23S rDNA genes from all of the 12 bacterial species *** hundred and forty fecal samples from the diarrhea patients were detected using the improved RDB ***:The methods could identify the 12 intestinal pathogens specifi cally, and the detection limit was as low as 103 *** consistent detection rate of the improved RDB assay compared with the traditional culture method was up to 88.75%.CONCLUSION:The hybridization results indicated that the improved RDB assay developed was a reliable method for the detection of intestinal pathogen in fecal samples.

关键词： Immunoblotting Intestinal pathogens Feces

Spatial variations of terrain and their impacts on landscape patterns in the transition zone from mountains to plains—A case study of Qihe River Basin in the Taihang Mountains

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Science China Earth Sciences 2018年第4期61卷 450-461页

作者： Jingjing ZHANG Wenbo ZHU Fang ZHAO lianqi ZHU Maojuan li ming ZHU Xiaodong ZHANG College of Environment and Planning Henan University

Terrain plays a key role in landscape pattern formation, particularly in the transition zones from mountains to *** the relationships between terrain characteristics and landscape types in terrain-complex areas can help reveal the mechanisms underlying the relationships. In this study, Qihe River Basin, situated in the transition zone from the Taihang Mountains to the North-China Plain, was selected as a case study area. First, the spatial variations in the relief amplitudes(i.e.,high-amplitude terrain undulations) were analyzed. Second, the effects of relief amplitudes on the landscape patterns were indepth investigated from the perspectives of both landscape types and landscape indices. Finally, a logistic regression model was employed to examine the relationships between the landscape patterns and the influencing factors(natural and human) at different relief amplitudes. The results show that with increasing relief amplitude, anthropogenic landscapes gradually give in to natral landscapes. Specifically, human factors normally dominate the gentle areas(e.g., flat areas) in influencing the distribution of landscape types, and natural factors normally dominate the highly-undulating areas(e.g., moderate relief areas). As for the intermediately undulating areas(i.e.,medium relief amplitudes), a combined influence of natural and human factors result in the highest varieties of landscape types. The results also show that in micro-relief areas and small relief areas where natural factors and human factors are more or less equally active,landscape types are affected by a combination of natural and human *** combination leads to a high fragmentation and a high diversity of landscape patterns. It seems that appropriate human interferences in these areas can be conducive to enhancing landscape diversity and that inappropriate human interferences can aggravate the problems of landscape fragmentation.

关键词： Transition zone Relief amplitude Mean turning-point analysis Landscape pattern Logistic regression analysis Taihang Mountains

Mass transfer analyses of reactive boundary schemes for lattice Boltzmann method with staircase approximation

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Advances in Aerodynamics 2024年第1期6卷 421-441页

作者： Zi-Xiang Tong ming-Jia li Yanxia Du Xianxu Yuan National Key Laboratory of Science and Technology on Aero‑Engine Aero-Thermodynamics School of Energy and Power EngineeringBeihang UniversityBeijing 100191China School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Aerodynamics Mianyang 621000China

Lattice Boltzmann(LB)methods with reactive boundary conditions are widely used in pore-scale simulations of dissolution and ablation *** staircase approxi-mation of curved boundary is often employed because of its simplicity in handling solid structure *** this work,the mass transfer of two typical LB reactive boundary schemes are analyzed for the staircase *** Type I boundary scheme is based on relations of local distribution functions and a wet-node boundary *** Type II boundary scheme adopts the half-way bounce-back ***-ary concentrations are determined by finite difference,and a link-wise boundary mesh is *** analyses demonstrate that for straight boundaries,both the boundary schemes have accurate mass transfer rates,which means the mass transfer calculated by exchanges of distribution functions is the same as that calculated by reaction *** curved boundaries with staircase approximation,including interfacial normal direc-tions in the Type I boundary scheme can provide accurate mass transfer for inclined straight ***,if the staircase boundary geometry is used directly without normal directions,the reaction rate will be ***-dimensional and two-dimensional reaction-diffusion processes with dissolution are simulated to validate the *** the boundary schemes work well for one-dimensional *** two-dimensional simulations,the Type II boundary scheme signifi-cantly overestimates the reaction rate,and stronger artificial anisotropic effects are *** Type I boundary scheme with normal directions has better performance,but error still exists.

关键词： Lattice Boltzmann Boundary condition Reaction Mass transfer Dissolution

Adaptive online prediction method based on LS-SVR and its application in an electronic system

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第12期13卷 881-890页

作者： Yang-ming GUO Cong-bao RAN Xiao-lei li Jie-zhong MA School of Computer Science and Technology Northwestern Polytechnical University Xi'an 710072 China

Health trend prediction has become an effective way to ensure the safe operation of highly reliable systems,and online prediction is always necessary in many real *** simultaneously obtain better or acceptable online prediction accuracy and shorter computing time,we propose a new adaptive online method based on least squares support vector regression(LS-SVR).This method adopts two *** approach is that we delete certain support vectors by judging the linear correlation among the samples to increase the sparseness of the prediction *** approach can control the loss of useful information in sample data,improve the generalization capability of the prediction model,and reduce the prediction *** other approach is that we reduce the number of traditional LS-SVR parameters and establish a modified simple prediction *** approach can reduce the calculation time in the process of adaptive online *** and a certain electric system application indicate preliminarily that the proposed method is an effective prediction approach for its good prediction accuracy and low computing time.

关键词： Adaptive online prediction Least squares support vector regression(LS-SVR) Electronic system

Improved AlGaN/GaN HEMTs Grown on Si Substrates Using Stacked AlGaN/AlN Interlayer by MOCVD

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Chinese Physics Letters 2011年第5期28卷 206-209页

作者： WANG Yong YU Nai-Sen li ming LAU Kei-May National Key Lab on High Power Semiconductor Lasers Changchun University of Science and TechnologyChangchun 130022 Photonics Technology Center Department of Electronic and Computer EngineeringHong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina

AlGaN/GaN high electron mobility transistors(HEMTs)are grown on 2-inch Si(111)substrates by *** stacked AlGaN/AlN interlayer with different AlGaN thickness and indium surfactant doped is designed and optimized to relieve the tensile stress during GaN epitaxial *** top 1.0μm GaN buffer layer grown on the optimized AlGaN/AlN interlayer shows a crack-free and shining *** XRD results show that GaN(002)FWHM is 480arcsec and GaN(102)FWHM is *** AGaN/GaN HEMTs with optimized and nonoptimized AlGaN/AlN interlayer are grown and processed for comparison and the dc and rf characteristics are *** the dc characteristics of the device with optimized AlGaN/AlN interlayer,maximum drain current density I_(dss)of 737mA/mm,peak transconductance G_(m)of 185mS/mm,drain leakage current density Ids of 1.7μA/mm,gate leakage current density I_(gs)of 24.8μA/mm and off-state breakdown voltage VBR of 67V are achieved with L_(g)/W_(g)/L_(g)/L_(g)=1/10/1/1μ*** the small signal rf characteristics of the device with optimized AlGaN/AlN interlayer,current gain cutoff frequency fT of 8.3 GHz and power gain cutoff frequency fmax of 19.9GHz are achieved with L_(g)/W_(g)/L_(g)/L_(g)=1/100/1/1μ***,the best rf performance with fT of 14.5 GHz and fmax of 37.3 GHz is achieved with a reduced gate length of 0.7μm.

关键词： AlGaN/GaN Si(111) HEMTs MOCVD

Predicting solutions of the Lotka-Volterra equation using hybrid deep network

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Theoretical & Applied Mechanics Letters 2022年第6期12卷 423-431页

作者： Zi-Fei lin Yan-ming liang Jia-li Zhao Jiao-Rui li School of Statistics Xi’an University of Finance and EconomicsXi’an 710100China China(Xi’an)Institute for Silk Road Research Xi’an 710100China

Prediction of Lotka-Volterra equations has always been a complex problem due to their dynamic *** this paper,we present an algorithm for predicting the Lotka-Volterra equation and investigate the prediction for both the original system and the system driven by *** demonstrates that deep learning can be applied in dynamics of *** is the first study that uses deep learning algorithms to predict Lotka-Volterra *** numerical examples are presented to illustrate the performances of the proposed algorithm,including Predator nonlinear breeding and prey competition systems,one prey and two predator competition systems,and their respective *** the results suggest that the proposed algorithm is feasible and effective for predicting Lotka-Volterra ***,the influence of the optimizer on the algorithm is discussed in *** results indicate that the performance of the machine learning technique can be improved by constructing the neural networks appropriately.

关键词： Lotka-Volterra equations HDN-LV algorithm Stochastic Lotka-Volterra equations Parameter optimization

Total ionizing dose effects on graphene-based charge-trapping memory

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Science China(Information Sciences) 2019年第12期62卷 207-214页

作者： Kai XI Jinshun BI SANDip MAJUMDAR Bo li Jing liU Yannan XU ming liU Laboratory of Microelectronics Devices and Integrated Technology Institute of MicroelectronicsChinese Academy of Sciences School of Microelectronics University of Chinese Academy of Sciences

This study investigates the total ionizing dose effects in graphene-based charge-trapping memory(GCTM) capacitors by using60 Co γ-irradiation. Electrical properties including C-V hysteresis window,gate leakage current, and flat band voltage shifts are evaluated with ionizing dose levels up to 1 Mrad(Si).The C-V hysteresis memory window is hardly affected by the irradiation. The gate leakage current increases with the increase of ionizing dose due to the multiple-trap assisted tunneling mechanism. Significant electrical degrade of the devices in programmed and erased states has been observed with the increase of the dose levels. Mechanisms behind the degradation are attributed to the photo-emission in the graphene nanodisc charge-trapping sets, radiation-induced holes trapping in the peripheral oxides, and the recombination of the stored electrons with the radiation-induced holes.

关键词： graphene non-volatile memories radiation trap-assisted tunneling leakage current