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Stream Surface Strip Element Method and Simulation of Three-Dimensional Deformation of Continuous Hot Rolled Strip

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Journal of Iron and Steel Research International 2004年第2期11卷 18-24页

作者： LIU Hong-min wang ying-rui Yanshan University

A new method,the stream surface strip element method,for simulating the three-dimensional deformation of plate and strip rolling process was *** rolling deformation zone was divided into a number of stream surface(curved surface)strip elements along metal flow traces,and the stream surface strip elements were mapped into the corresponding plane strip elements for analysis and *** longitudinal distributions of the lateral displacement and the altitudinal displacement of metal were respectively constructed to be a quartic curve and a quadratic curve,of which the lateral distributions were expressed as the third-power spline function,and the altitudinal distributions were fitted in the quadratic *** the flow theory of plastic mechanics,the mathematical models of the three-dimensional deformations and stresses of the deformation zone were *** with the streamline strip element method proposed by the first author of this paper,the stream surface strip element method takes into account the uneven distributions of stresses and deformations along altitudinal direction,and realizes the precise three-dimensional analysis and *** simulation example of continuous hot rolled strip indicates that the method and the model accord with facts and provide a new reliable engineering-computation method for the three-dimensional mechanics simulation of plate and strip rolling process.

关键词： hot-rolling strip plate three-dimensional deformation stream surface strip element method unit rolling pressure friction stress tension stress

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东部区域核事故核素大气扩散特征研究

科学技术与工程 2024年第12期24卷 4976-4982页

作者：郭瑞萍王瑞英岳峰李雯婷郜建伟生态环境部核与辐射安全中心北京102401

针对核事故核素大气环境影响,建立一种基于区域尺度天气预报模式WRF(weather research forecasting model)的核素不同尺度大气扩散特征分析方法。以东部多个核电厂为研究对象,基于再分析气象数据(final reanalysis data,FNL)驱动WRF,并... 详细信息

针对核事故核素大气环境影响,建立一种基于区域尺度天气预报模式WRF(weather research forecasting model)的核素不同尺度大气扩散特征分析方法。以东部多个核电厂为研究对象,基于再分析气象数据(final reanalysis data,FNL)驱动WRF,并结合高斯大气扩散模式研究了东部区域尺度以及核电厂周边尺度的核事故核素大气扩散分布特征。结果表明:区域尺度大气弥散因子最大值主要分布在计算区域的西部地区,并且其随距离增加呈现下降趋势,距离500 m和5000 m处二者相差约一个量级。核电厂周边尺度大气弥散因子最大值比区域尺度大气弥散因子最大值偏低一个量级;除秦山核电厂外,其他核电厂距离500 m和5000 m处的大气弥散因子最大值相差约一个量级。不同核电厂大气弥散因子最大值出现的方位受厂址气象条件影响存在显著差异;东部沿海地区比内陆大气扩散能力较强,有利于放射性核素的大气传输。

关键词：核事故区域尺度大气扩散放射性核素核电厂

Thickness and Shape Synthetical Adjustment for DC Mill Based on Dynamic Nerve-Fuzzy Control

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Journal of Iron and Steel Research International 2004年第6期11卷 25-29页

作者： JIA Chun-yu wang ying-rui ZHOU Hui-feng Yanshan University

Due to the complexity of thickness and shape synthetical adjustment system and the difficulties to build a mathematical model,a thickness and shape synthetical adjustment scheme on DC mill based on dynamic nerve-fuzzy control was put forward,and a self-organizing fuzzy control model was *** structure of the network can be optimized *** the course of studying,the network can automatically adjust its structure based on the specific questions and make its structure the *** input and output of the network are fuzzy sets,and the trained network can complete the composite relation,the fuzzy *** decreasing the off-line training time of BP network,the fuzzy sets are *** simulation results indicate that the self-organizing fuzzy control based on dynamic neural network is better than traditional decoupling PID control.

关键词： dynamic BP network self-organizing fuzzy control encode DC mill thickness shape synthetical adjustment

DIAGNOSTIC VALUE OF INTERICTAL DIFFUSION-WEIGHTED IMAGING IN EVALUATION OF INTRACTABLE TEMPORAL LOBE EPILEPSY

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Chinese Medical Sciences Journal 2008年第2期23卷 68-72页

作者： rui wang Sa-ying Li Min Chen Cheng Zhou Department of Radiology Beijing Hospital Beijing 100730

Objective To explore the ability of interictal diffusion-weighted imaging(DWI)to localize the temporal lobe of seizure origin and to predict postoperative seizure control in patients with temporal lobe epilepsy(TLE).Methods Twenty-seven patients with intractable TLE considered for surgery and 19 healthy volunteers were studied with conventional magnetic resonance imaging(MRI)and *** diffusion coefficients(ADCs)of bilateral hippocampi in both TLE patients and control subjects were *** to either temporal lobe with hippocampal ADC was based on the threshold values derived from ±1SD of right/left ratios in normal *** the postoperative pathology was *** Hippocampal ADCs were higher on the side of surgery compared with those on the contralateral side as well as the ipsilateral side in control subjects [resected side(109.8±7.3)×10-5 cm2/s,contralateral side(91.7±4.7)×10-5 cm2/s,control subjects(81.6±5.2)×10-5 cm2/s,all P0.05).Conclusions Conventional MRI is a sensitive method to detect hippocampal *** of the right/left hippocampal ADC ratio for lateralizing to the side of surgery is very high,but it isn't a better predictor of surgical outcome.

关键词： magnetic resonance imaging temporal lobe epilepsy epilepsy surgery

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废旧轮胎胶粉级配对橡胶沥青性能的影响

合成橡胶工业 2024年第1期47卷 72-76页

作者：王国清王瑞颖秦禄生刘延雷王新强河北工业大学土木与交通学院天津300401 河北交通投资集团有限公司石家庄050090 益路恒丰衡水沥青科技有限公司河北衡水053400

为确定胶粉级配对橡胶沥青性能的影响,选取8种胶粉级配,基于不同胶粉级配进行定量评价,分别采用常规性能、流变性能和弯曲蠕变劲度试验评价了胶粉级配对橡胶沥青常规性能和高低温性能的影响,通过热重、荧光显微镜和溶解度测试分析了不... 详细信息

为确定胶粉级配对橡胶沥青性能的影响,选取8种胶粉级配,基于不同胶粉级配进行定量评价,分别采用常规性能、流变性能和弯曲蠕变劲度试验评价了胶粉级配对橡胶沥青常规性能和高低温性能的影响,通过热重、荧光显微镜和溶解度测试分析了不同胶粉级配橡胶沥青的微观性能。结果表明,随着胶粉级配变细,橡胶沥青的针入度上升,软化点和黏度下降,延度和储存稳定性得到提高。级配越粗对橡胶沥青高温性能的提升效果越好,而级配越细对低温性能提升效果越好。胶粉级配参数与橡胶沥青性能有良好的相关性。粗级配胶粉沥青的高温稳定性更好;细级配胶粉在沥青中有更好的相容性和更大的降解程度,从而提升了橡胶沥青的储存稳定性。

关键词：橡胶沥青胶粉级配级配参数沥青性能

Low-viscosity oligoether esters(OEEs)as high-efficiency lubricating oils:Insight on their structure‒lubricity relationship

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Friction 2024年第6期12卷 1133-1153页

作者： Hanwen wang ying wang Ping WEN Lin MA Mingjin FAN rui DONG Chunhua ZHANG Shaanxi Key Laboratory of Phytochemistry College of Chemistry&Chemical EngineeringBaoji University of Arts and SciencesBaoji 721013China Key Laboratory of Shaanxi Province for Development and Application of New Transportation Energy Chang’an UniversityXi’an 710064China

Development of energy-efficient lubricants is a way to reduce energy consumption for transportation,with the tendency to design molecules that are beneficial in reducing the viscosity of synthetic *** esters(OEEs),as a low-viscosity ester base oil,have characteristics such as simple synthesis and excellent lubrication effect;however,the application of OEEs in tribology field has rarely been *** objective of the present study is to investigate the effect of structure on the lubricating performance of OEEs and to develop a predictive model for OEEs based on quantitative structure‒property relationship(QSPR)through a combination of experiment and statistical *** showed that glycol chains contribute positively to lubrication with the ether functional groups increasing the sites of *** to branched-chain OEEs,straight-chain OEEs exhibited reduced wear,which was mainly due to the thicker adsorption film formed by the straight-chain ***,carbon films were detected on lightly worn surfaces,indicating that OEEs underwent oxidation during the friction *** on the results of principal component analysis(PCA)and partial least squares(PLS),it could be found that the predictive models of viscosity‒temperature performance,thermal stability performance,coefficient of friction(COF),and wear volume(WV)performed well and *** them,COF and WV can be best predicted with an R^(2) of about 0.90.

关键词： oligoether esters(OEEs) low-viscosity ester friction wear quantitative structure-property relationship(QSPR)

Simultaneously enhanced electrochemical performance and air stability of Ni-rich cathode with a modified washing process

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Rare Metals 2024年第1期43卷 87-97页

作者： Ben-rui Hu ying-Yi Yuan Yu-Cheng wang Xun-Hui Xiong School of Environment and Energy Guangdong Provincial Key Laboratory of Advanced Energy Storage MaterialsSouth China University of TechnologyGuangzhou 510640China

Water washing has been regarded as one of the most effective strategies to remove surface residual lithium of nickel-rich layered oxides for lithium-ion batteries(LIBs).However,the loss of lattice lithium during the water washing process deteriorates the electrochemical performances and air ***,washing the LiNi_(0.90)Co_(0.05)Al_(0.02)O_(2)(NCA) with ammonium dihydrogen phosphate(NH_(4)H_(2)PO_(4)) solution has been proposed to simultaneously enhance electrochemical performances and air stability,in which in-situ generated Li_(3)PO_(4) coating layer on surface of NCA can suppress the loss of lattice ***,as a fast ionic conductor,Li_(3)PO_(4) coating layer on NCA can prevent the direct contact with electrolyte/*** a result,the NH_(4)H_(2)PO_(4) solution washed NCA cathode can deliver a high capacity of131.9 mAh·g^(-1) at 10.0C rate as well as impressive cycle stability with a capacity retention of 83.1% after 100 cycles at 1.0C,much higher than those of water washed NCA(WS-NCA) *** exposed in air for 7 days,the NH_(4)H_(2)PO_(4) solution washed NCA electrode can more effectively maintain the structural integrity as well as the electrochemical performances than water-washed *** work provides a simple and effective approach to enhance the cycle stability and air stability of Nickel-rich cathode materials.

关键词： Layered Ni-rich cathode Residual lithium Li_(3)PO_(4)coating Rate performance Air stability

Fabrication and characterization of multi-scale coated boron powders with improved combustion performance:A brief review

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Defence Technology（防务技术） 2024年第1期31卷 27-40页

作者： rui Liu Danfeng Yang Kunyu Xiong ying-Lei wang Qi-Long Yan Science and Technology on Combustion Internal Flow and Thermo-structure LaboratoryNorthwestern Polytechnical UniversityXi'an710072China Xi'an Modern Chemistry Research Institute Xi'an710065China

Boron has high mass and volume calorific values,but it is difficult to ignite and has low combustion *** literature review summarizes the strategies that are used to solve the above-mentioned problems,which include coatings of boron by using fluoride compounds,energetic composites,metal fuels,and metal *** techniques include recrystallization,dual-solvent,phase transfer,electrospinning,*** one of the effective coating agents,the fluorine compounds can react with the oxide shell of boron *** comparison,the energetic composites can effectively improve the flame temperature of boron powder and enhance the evaporation efficiency of oxide film as a condensed *** and metal oxides would react with boron powder to form metal borides with a lower ignition point,which could reduce its ignition temperature.

关键词： Boron powder coating Structure and morphology Condensed phase thermal reaction Ignition and combustion

On Learners＇ Perceptions of Taking MOOC in Learning Intercultural Communication （IC） A Case Study of the IC MOOC from SISU

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Journal of Literature and Art Studies 2018年第8期8卷 1282-1288页

作者： wang rui-ying South China Business College (SCBC) Guangdong University of Foreign Studies (GDUFS) Guangdong China

The topic of taking MOOC in learning Intercultural Communication （IC） is an under-researched area, and there has been little empirical research published which focuses on students＇ perceptions. This study explores learner＇s perceptions of taking the MOOC from SISU in learning IC with both a quantitative and qualitative data collection and analysis, which focuses on students＇ viewpoints about their MOCC learning experience, development in Intercultural Communication Competence （ICC） and their problems in Learning MOOC.

关键词： MOOC perceptions learning experience Intercultural Communication Competence (ICC) problems