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Pressure leaching of converter vanadium slag with waste titanium dioxide

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Rare Metals 2016年第7期35卷 576-580页

作者： Guo-Quan Zhang Ting-An Zhang Ying Zhang Guo-Zhi lv yan Liu zhuo-Lin Liu Key Laboratory of Ecological Utilization of Multi-Metal Intergrown Ores of Ministry of Education School of Materials and MetallurgyNortheastern University

The process of pressure leaching the converter vanadium slag with waste titanium dioxide without roasting was studied. Mineralogy analysis indicates that the con- verter vanadium slag contains mainly three mineral phases： magnetite, titanium magnetite, and silicate phase. Vana- dium is in combination with iron, titanium, manganese, aluminum, and silicon. The impacts of leaching tempera- ture, leaching time, stirring speed, liquid-to-solid ratio, and initial leaching agent concentration were investigated on the waste titanium dioxide leaching process. The results indi- cate that under the optimal conditions, the vanadium and the iron leaching rates are 96.85 % and 93.50 %, respectively, and the content of titanium is 12.6 % in the residue. The main mineral phases for the residues under the optimal operation conditions are quartz, ilmenite, anatase, and sili- cate phase, and the residues can be reused as the extraction of titanium raw materials for titanium dioxide production technology by the sulfate method.

关键词： Vanadium Waste titanium dioxide Pressure leaching Resource utilization

Spin Caloritronic Transport of Tree-Saw Graphene Nanoribbons

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Chinese Physics Letters 2019年第1期36卷 48-51页

作者： Yu-zhuo lv Peng ZHAO School of Physics and Technology University of Jinan

Using density functional theory combined with non-equilibrium Green's function method, we investigate the spin caloritronic transport properties of tree-saw graphene nanoribbons. These systems have stable ferromagnetic ground states with a high Curie temperature that is far above room temperature and exhibit obvious spin-Seebeck effect. Moreover, thermal colossal magnetoresistance up to 1020% can be achieved by the external magnetic field modulation. The underlying mechanism is analyzed by spin-resolved transmission spectra, current spectra and band structures.

关键词： Spin Caloritronic Transport Tree-Saw Graphene Nanoribbons Density functional theory

Combining neural network-based method with heuristic policy for optimal task scheduling in hierarchical edge cloud

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Digital Communications and Networks 2023年第3期9卷 688-697页

作者： zhuo Chen Peihong Wei yan Li College of Computer Science and Engineering Chongqing University of TechnologyChongqing200433China School of Artificial Intelligence Chongqing University of TechnologyChongqing200433China

Deploying service nodes hierarchically at the edge of the network can effectively improve the service quality of offloaded task requests and increase the utilization of *** this paper,we study the task scheduling problem in the hierarchically deployed edge *** first formulate the minimization of the service time of scheduled tasks in edge cloud as a combinatorial optimization problem,blue and then prove the NP-hardness of the *** from the existing work that mostly designs heuristic approximation-based algorithms or policies to make scheduling decision,we propose a newly designed scheduling policy,named Joint Neural Network and Heuristic Scheduling(JNNHSP),which combines a neural network-based method with a heuristic based *** takes the Sequence-to-Sequence(Seq2Seq)model trained by Reinforcement Learning(RL)as the primary policy and adopts the heuristic algorithm as the auxiliary policy to obtain the scheduling solution,thereby achieving a good balance between the quality and the efficiency of the scheduling ***-depth experiments show that compared with a variety of related policies and optimization solvers,JNNHSP can achieve better performance in terms of scheduling error ratio,the degree to which the policy is affected by re-sources limitations,average service latency,and execution efficiency in a typical hierarchical edge cloud.

关键词： Edge cloud Task scheduling Neural network Reinforcement learning

Research on mode localization of reticulated shell structures

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Earthquake Engineering and Engineering Vibration 2011年第1期10卷 75-84页

作者： yan Weiming Wang zhuo He Haoxiang Beijing Laboratory of Earthquake Engineering and Structural Retrofit Beijing University of Technology Beijing 100124 China The Open University of China Beijing 100031 China

Reticulated shell structures （RSSs） are characterized as cyclically periodic structures. Mistuning of RSSs will induce structural mode localization. Mode localization has the following two features： some modal vectors of the structure change remarkably when the values of its physical parameters （mass or stiffness） have a slight change; and the vibration of some modes is mainly restricted in some local areas of the structure. In this paper, two quantitative assessment indexes are introduced that correspond to these two features. The first feature is studied through a numerical example of a RSS, and its induced causes are analyzed by using the perturbation theory. The analysis showed that internally, mode localization is closely related to structural frequencies and externally, slight changes of the physical parameters of the structure cause instability to the RSS. A scaled model experiment to examine mode localization was carried out on a Kiewit single-layer spherical RSS, and both features of mode localization are studied. Eight tests that measured the changes of the physical parameters were carried out in the experiment. Since many modes make their contribution in structural dynamic response, six strong vibration modes were tested at random in the experimental analysis. The change and localization of the six modes are analyzed for each test. The results show that slight changes to the physical parameters are likely to induce remarkable changes and localization of some modal vectors in the RSSs.

关键词： reticulated shell structure mistuning mode localization perturbation theory seismic performance analysis damage identification

Multi-factor Analysis of Reflection from Granite Surfaces

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Journal of China University of Mining and Technology 2007年第2期17卷 255-257页

作者： ZHAO Nai-zhuo yan Lei ZHAO Yun-sheng lv Yun-feng WU Tai-xia College of Urban and Environmental Science Northeast Normal University Changchun Jilin 130024 China Beijing Key Lab of Spatial Information Integration and 3S Application Peking University Beijing 100871 China

Many earlier experiments have shown that reflection from rock surfaces depends upon surface roughness,in-cidence zenith angle,viewing zenith angle,incidence azimuth and viewing azimuth. However,no research exists show-ing the interaction effects of these variables. Using granite as a model surface,we have designed an orthogonal,two level test having seven factors. Analysis of variance shows that surface roughness,relative viewing azimuth,and the in-teraction between these two factors are the largest sources of variance in our experiment. Hence we should include the interaction term in reflection models of granite.

关键词： granite bidirectional reflectance mutual effect orthogonal test

Robust Estimation of Semiparametric Transformation Model for Panel Count Data

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Journal of Systems Science & Complexity 2021年第6期34卷 2334-2356页

作者： FENG yan WANG Yijun WANG Weiwei CHEN zhuo Department of Otolaryngology Head&Neck SurgeryThe First HospitalShanxi Medical UniversityTaiyuan 030001China School of Statistics and Mathematics Zhejiang Gongshang UniversityHangzhou 310018China School of Electronic and Optical Engineering Nanjing University of Science and TechnologyNanjing 210014China

Panel count data are frequently encountered when study subjects are under discrete ***,limited literature has been found on variable selection for panel count *** this paper,without considering the model assumption of observation process,a more general semiparametric transformation model for panel count data with informative observation process is developed.A penalized estimation procedure based on the quantile regression function is proposed for variable selection and parameter estimation *** consistency and oracle properties of the estimators are established under some mild *** simulations and an application are reported to evaluate the proposed approach.

关键词： B-spline function panel count data quantile regression semiparametric transformation model variable selection

同方期刊数据库

Cooling and Optimization in the Groove of the Outer Rotor HubMotor

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Frontiers in Heat and Mass Transfer 2024年第5期22卷 1443-1460页

作者： zhuo Liu Yecui yan School of Mechanical and Automotive Engineering Shanghai University of Engineering ScienceShanghai201620China

The external rotor hub motor adopts direct drive mode,no deceleration drive device,and has a compact *** axial size is smaller than that of a deceleration-driven hub motor,which greatly reduces the weight of the vehicle and increases the cruising range of the *** of the limited special working environment and performance requirements,the hub motor has a small internal space and a large heat generation,so it puts forward higher requirements for heat dissipation *** the external rotor hub motor,a new type of in-tank watercooled structure of hub motor was proposed to improve its cooling effect and ***,the threedimensional finite element model of the motor is established to analyze the characteristics of motor loss and temperature field ***,the cooling performance of different cooling structures in the tank was ***,the thermal network model and three-dimensional finite element analysis were used to optimize the water-cooled structure in the tank,and the power density of themotor was improved by improving the cooling performance under the condition of volume limitation of the hub *** results show that the cooling effect of the proposed water-cooled structure in the tank is significant under the condition of constant power *** to natural ventilation,the maximum temperature was reduced by 33.13°C and the cooling effect was increased by about 27.7%.

关键词： Outer rotor hub motor temperature field water cooling in the tank motor loss thermal networks high torque density

DTCWT-based zinc fast roughing working condition identification

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Chinese Journal of Chemical Engineering 2018年第8期26卷 1721-1726页

作者： zhuo He Zhaohui Tang Zhihao yan Jinping Liu College of Information Science and Enineering Central South University Changsha 410083China Key Laboratory of High Performance Computing and Stochastic Information Processing of Ministry of Education of China College of Mathematics and Computer ScienceHunan Normal UniversityChangsha 410081China

The surface texture of mineral flotation froth is well acknowledged as an important index of the flotation *** surface texture feature closely relates to the flotation working conditions and hence can be used as a visual indicator for the zinc fast roughing working condition. A novel working condition identification method based on the dual-tree complex wavelet transform(DTCWT) is proposed for process monitoring of zinc fast ***-level DTCWT is implemented to decompose the froth image into different directions and resolutions in advance, and then the energy parameter of each sub-image is extracted as the froth texture feature. Then, an improved random forest integrated classification(i RFIC) with 10-fold cross-validation model is introduced as the classifier to identify the roughing working condition, which effectively improves the shortcomings of the single model and overcomes the characteristic redundancy but achieves higher generalization performance. Extensive experiments have verified the effectiveness of the proposed method.

关键词： DTCWT Working condition Integrated classification model Zinc fast roughing

Research progress of magnetic resonance imaging contrast agents

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Chinese Science Bulletin 2001年第15期46卷 1233-1237页

作者： Guoping yan Renxi zhuo Wuhan Univ Minist Educ China Dept Chem Lab Biomed Polymer Mat Wuhan 430072 Peoples R China

Magnetic resonance imaging (MRI) is a clinical diagnostic modality, which has become popular in hospitals around the world. Approximately 30% of MRI exams include the use of contrast agents. The research progress of the paramagnetic resonance imaging contrast agents was described briefly. Three important approaches in the soluble paramagnetic resonance imaging contrast agents design including nonionic, tissue-specific and macromolecular contrast agents were investigated. In addition, the problems in the research and development in future were discussed.

关键词： magnetic resonance imaging (MRI) contrast agents gadolinium(m) complexes tissue-specific.