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Scattering Versus Blowup Beyond the Mass-Energy Threshold for the Davey–Stewartson Equation in R^(3)

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Acta Mathematica Sinica,English Series 2021年第9期37卷 1415-1436页

作者： Yan Fang GAO zhi yong wang School of Mathematics and Statistics&Fujian Key Laboratory of Mathematical Analysis and Applications Fujian Normal UniversityFuzhou 350117P.R.China

We study the Cauchy problem for the Davey–Stewartson equation i?tu+Δu+|u|^(2) u+E1(|u|^(2))u=0,(t,x)∈R×R^(3).The dichotomy between scattering and finite time blow-up shall be proved for initial data with finite va... 详细信息

关键词： Davey–Stewartson equation scattering blow-up finite variance

Application of internal standard method in recombinant luminescent bacteria test

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Journal of Environmental Sciences 2015年第9期27卷 128-134页

作者： yong-zhi wang Dan Li Miao He Environmental Simulation and Pollution Control (ESPC) State Key Joint Laboratory School of Environment Tsinghua University Fudan University Department of Environmental Science & Engineering

Mercury and its organic compounds have been of severe concern worldwide due to their damage to the ecosystem and human health. The development of effective and affordable technology to monitor and signal the presence of bioavailable mercury is an urgent *** Mer gene is a mercury-responsive resistant gene, and a mercury-sensing recombinant luminescent bacterium using the Mer gene was constructed in this study. The mer operon from marine Pseudomonas putida strain SP1 was amplified and fused with prompterless lux CDABE in the p UCD615 plasmid within Escherichia coli cells, resulting in p THE30–E. *** recombinant strain showed high sensitivity and specificity. The detection limit of Hg^2＋was 5 nmol/L, and distinct luminescence could be detected in 30 min. Cd^2＋, Cu^2＋, Zn^2＋, Ca^2＋,Pb^2＋, Mg^2＋, Mn^2＋, and Al^3＋did not interfere with the detection over a range of 10-5–1 m *** of recombinant luminescent bacteria testing in environmental samples has been a controversial issue： especially for metal-sensing recombinant strains, false negatives caused by high cytotoxicity are one of the most important issues when applying recombinant luminescent bacteria in biomonitoring of heavy metals. In this study, by establishing an internal standard approach, the false negative problem was overcome;furthermore, the method can also help to estimate the suspected mercury concentration,which ensures high detection sensitivity of bioavailable Hg2＋.

关键词： Mercury Biomonitoring Recombinant luminescent bacteria p THE30–E.coli Internal standard method False negative

Influencing factors and mechanism of water absorption process of iron ores during sintering

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International Journal of Minerals,Metallurgy and Materials 2014年第2期21卷 122-130页

作者： Guo-liang Zhang Sheng-li Wu Juan Zhu yong-zhi wang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

The appropriate content and distribution of sinter moisture play an important role in the granulation of iron ores. In this study, the effects of porosity, size distribution, and particle shape on the water absorption rate （WAR） of four types of iron ores were analyzed by using the immersion method and capillary water absorption method. In addition, the mechanism underlying the water absorption process in iron ores was unraveled. It is found that the WARs of iron ores decrease quickly with the increase in water absorption time at the initial stages of water absorption. With further increase in absorption time, the WARs decrease gradually, until near 0. Iron ores with higher porosity, smaller particle size, and plate-like structure have the higher WARs. Compared with pores in the single-particle iron ore, voids among particles in the multi-particle iron oxide play an important role at the initial stages of water absorption. The water absorption mechanism of all single-particle and multi-particle iron ores analyzed in this study includes four steps, wherein the first three steps play a significant role in the sintering pro-cess.

关键词： iron ores sintering water absorption factor analysis

The Spectrality of a Class of Fractal Measures on R^(n)

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Acta Mathematica Sinica,English Series 2023年第5期39卷 952-966页

作者： Jing Cheng LIU zhi yong wang Yao LIU Ya SHI Key Laboratory of Computing and Stochastic Mathematics(Ministry of Education) School of Mathematics and StatisticsHunan Normal UniversityChangsha 410081P.R.China School of Mathematics and Statistics Hunan First Normal UniversityChangsha 410205P.R.China

Let M=ρ^(-1)I∈Mn(R)be an expanding matrix with 0<|ρ|<1 and D■Z^(n)be a finite digit set with O∈D and Z(mD)■Z(mD)■Z(mD)∪{0}■m^(-1)z^(n)for a prime m,where Z(mD):=(Ede emi(a)=O),LetμM.D be theassociatedsel-simiar measure defined by ***)-ZaeDμM,D(M()-d).In this paper,the necessary and sufficient conditions for L2(μM,D)to admit infinite orthogonal exponential functions are ***,by using the order theory of polynomial,we estimate the number of orthogonal exponential functions for all cases that L^(2)(μM,D)does not admit infinite orthogonal exponential functions.

关键词： Fractal spectral measure orthogonal exponentials Fourier transform spectrum

Henry Reaction in Aqueous Media: Chemoselective Addition of Aldehydes

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Chinese Chemical Letters 2003年第4期14卷 355-358页

作者： Cun Liu ZHOU Yu Qing ZHOU zhi yong wang Department of Chemistry University of Science&Technology of ChinaHefei 230026

The chemoselective addition of aldehydes in aquoues medium was obtained under mild condition using improved Henry reaction.

关键词： Chemoselective addition water Henry reaction.

Integrated hybrid sensing and microenergy for compact active microsystems

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Microsystems & Nanoengineering 2022年第3期8卷 209-221页

作者： Hai-Tao Deng zhi-yong wang Y-Lin wang Dan-Liang Wen Xiao-Sheng Zhang School of Electronic Science and Engineering University of Electronic Science and Technology of China611731 ChengduChina

Wearable electronics,as essential components of the Internet of Things(IoT),have attracted widespread attention,and the trend is to configure attractive wearable smart microsystems by integrating sensing,powering,and other,***,we developed an elastic hybrid triboelectric-electromagnetic microenergy harvester(named EHTE)to realize hybrid sensing and microenergy *** EHTE is a highly integrated triboelectric nanogenerator(TENG)and electromagnetic nanogenerator(EMG).Based on the triboelectric-electromagnetic hybrid mechanism,an enhanced electrical output of the EHTE was achieved successfully,which demonstrates the feasibility of the EHTE for microelectronics ***,with the merits of the EMG,the developed hybrid microenergy harvester integrated both active frequency sensing and passive inductive sensing ***,the almost linear correlation of the electromagnetic outputs to the frequencies of the external stimulus endowed the proposed EHTE with an outstanding active frequency sensing *** addition,due to the unique structural configuration of the EMG(i.e,a conductive permanent magnet(PM),hybrid deformation layer,and flexible printed circuit board(FPCB)coil),an opportunity was provided for the developed EHTE to serve as a passive inductive sensor based on the eddy current effect(ie.,a form of electromagnetic induction).Therefore,the developed EHTE successfully achieved the integration of hybrid sensing(i.e,active frequency sensing and passive inductive sensing)and microenergy(ie,the combination of electromagnetic effect and triboelectric effect)within a single device,which demonstrates the potential of this newly developed EHTE for wearable electronic applications,especially in applications of compact active microsystems.

关键词： inductive energy generator

Characteristics of force chains in frictional interface during abrasive flow machining based on discrete element method

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Advances in Manufacturing 2018年第4期6卷 355-375页

作者： Tian-Xun Xiu Wei wang Kun Liu zhi-yong wang Dao-Zhu Wei School of Mechanical Engineering. Hefei University of Technology Hefei 230009 People's Republic of China Changzhou Borui Power Automation Equipment Co. Ltd Changzhou 213025 Jiangsu People's Republic of China

Abrading is a very important sub-technology of the surface treatment tech no logy with vast applications in the industry. This study aims at analyzing the inherent laws of friction systems during abrading. In particle flow code modeling, the abrading process can be simplified to the movement of particles in a parallel-plate shear friction system. In this study, the PFC2D software is used to construct the particle flow friction system with the set of parallel plates and the model parameters according to the abrading processing equipment and processing materials, control the simulation of a single variable, and compare the output data to estimate the impact of change of parameters on the force chain. The simulation results show that the shear dilatancy can be divided into three stages: plastic strain, macroscopic failure, and granular recombination stages. The distribution and load rates of the weak force chains depend on the load, velocity, friction coefficient between granules, granular diameter, and number of granular layers. The number of granular layers and the load increase cause the direction of the force chain to be oriented with the vertical direction, and the force chains move toward the horizontal direction as the velocity increases. The increase in load does not cause the shear dilatancy stage to occur;the velocity, friction coefficient between granules, and granular diameter increase cause the shear dilatancy to occur gradually.

关键词： Abrasion Force Machining

Tuning the Fermi level in Bi2Se3 bulk materials and transport devices

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Frontiers of physics 2012年第2期7卷 160-164页

作者： zhi-yong wang (1) Peng Wei (1) Jing Shi (1) University of California Department of Physics & Astronomy Riverside USA (GRID:grid.266097.c) (ISNI:***)

Bi2Se3 has been predicted to be a three-dimensional （3D） topological insulator （TI） with Dirac fermions residing on the two-dimensional （2D） surface. Unique transport properties such as high carrier mobility due to the suppressed backscattering are expected for the Dirac fermions. In order to eliminate the contribution of the bulk carriers, therefore, to place the Fermi level in the band gap of Bi2Se3, we first introduce various amounts of Ca dopants into the crystal to realize the bulk insulating state. Then by avoiding uncontrolled heating and electron beam irradiation in the nanofabrication process, we maintain the insulating state in thin devices. By sweeping the gate voltage, we have observed a conductivity minimum that is expected for the Dirac fermions in the band gap of 3D TIs.

关键词： topological insulators Bi2Se3 transport properties nano-devices

A Novel Palladium-Catalyzed Reaction and Its Application in Preparation of Derivatives of Stilbazols

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Chinese Chemical Letters 2001年第5期12卷 399-402页

作者： zhi yong wang Chao JIANG Ji Hui WU Qing Xiang GUO Dept.of Chem. University of Science&Technology of ChinaHefei 230026

A novel palladium-catalyzed coupling reaction for the preparation of derivatives of stilbazoles was presented. A series of stilbazoles were synthesized firstly by this highly efficient method. From this reaction it wa... 详细信息

关键词： Palladium catalyzed preparation stilbazole