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车载式混砂车的改进设计

机电产品开发与创新 2024年第5期37卷 58-61页

作者：叶龙何恩光何政律北方重工集团有限公司辽宁沈阳110141 沈阳建筑大学机械工程学院辽宁沈阳110168

为适应国家机动车污染物排放标准的逐步提高以及原有混砂车管汇系统、液添系统和储存罐系统存在的不足,开展了车载式混砂车改进设计研究。研究了新的关键部件配置方案;设计了新的吸排转换管汇系统;取消原有100桶混砂车液添灌结构,在管... 详细信息

为适应国家机动车污染物排放标准的逐步提高以及原有混砂车管汇系统、液添系统和储存罐系统存在的不足,开展了车载式混砂车改进设计研究。研究了新的关键部件配置方案;设计了新的吸排转换管汇系统;取消原有100桶混砂车液添灌结构,在管路布置上进行了重新设计,改进为130桶混砂车液添系统;改进了混合罐,改进后容量达到1.5m^(3),配置液面自动控制装置实现了手动或自动控制;重新进行了参数计算,使改进设计的车载式混砂车满足了国家及行业标准要求,产品性能得到了提升,满足了石油天然气市场对车载式混砂车的需求。

关键词：车载式混砂车压裂

Two-dimensional halide perovskites:A review on their orientations

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Science China(Physics,Mechanics & Astronomy) 2023年第1期66卷 106-122页

作者： Taoyuze lv Yuhang Liang Feng Li Xudong Yang Jun Huang Rongkun zheng School of Physics The University of SydneySydney 2006Australia School of Chemical and Biomolecular Engineering The University of SydneySydney 2006Australia State Key Laboratory of Metal Matrix Composites School of Material Science and EngineeringShanghai Jiao Tong Universiy.Shanghai 200240China Joint Research Center for Clean Energy Materials Shanghai Jiao Tong UniversityShanghai 200240China

Two-dimensional halide perovskites,emerging materials with quantum well structures,demonstrate excellent physical properties,such as easily tunable band structures,hot-phonon bottleneck,photo-induced phase segregation,and spin-orbit coupling,and therefore hold great potential for various optoelectronic ***,this class of perovskite materials also possesses a unique anisotropic feature,and their orientations can highly affect their charge carrier behaviors and other related ***,effectively controlling the orientation of two-dimensional halide perovskites is of vital *** far,various methods,on the basis of different mechanisms have been developed to modulate the orientation,particularly the out-ofplane ***,we summarize recent advances in these strategies for enabling the out-of-plane orientation for twodimensional *** then systematically review the possible principles for tunning the orientation,followed by an overview of the remaining problems,particularly the microscopic mechanisms behind these modulation methods and their influences,and the future perspectives.

关键词： two-dimensional halide perovskite orientation solar cells optoelectronic devices

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二氯甲烷和甲醇共沸体系的分离模拟研究

齐鲁石油化工 2024年第2期52卷 106-110页

作者：吕才山李政马鹏程中国石化齐鲁分公司研究院山东淄博255400

基于Aspen Plus模拟软件,采用萃取精馏的工艺流程对二氯甲烷和甲醇共沸体系进行模拟分离,推荐以乙二醇为萃取剂,对各塔关键参数进行了优化,确定了最佳操作参数:萃取塔理论板数为49,原料进料位置为第40块理论板,进料量为1 000 kg/h,乙二... 详细信息

基于Aspen Plus模拟软件,采用萃取精馏的工艺流程对二氯甲烷和甲醇共沸体系进行模拟分离,推荐以乙二醇为萃取剂,对各塔关键参数进行了优化,确定了最佳操作参数:萃取塔理论板数为49,原料进料位置为第40块理论板,进料量为1 000 kg/h,乙二醇进料位置为第3块理论板,进料量为260 kg/h,可实现萃取塔塔顶采出质量分数为99.9%的二氯甲烷700 kg/h;萃取剂回收塔理论板数为10,进料位置为第3块理论板,回收塔塔顶采出质量分数为99.8%的甲醇300.3 kg/h,塔釜回收的萃取剂可返回利用。

关键词：二氯甲烷甲醇萃取精馏乙二醇

Topological r-entropy and measure-theoretic r-entropy of a continuous map

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Science China Mathematics 2011年第6期54卷 1197-1205页

作者： REN YunLi HE LianFai lv JinFeng zheng GuoPing College of Mathematics and Information Science Hebei Normal University Shijiazhuang 050016 China College of Mathematics and Information Technology Hebei Normal University of Science and Technology Qinhuangdao 066004 China

In this paper,we introduce the concept of measure-theoretic r-entropy of a continuous map on a compact metric space,and get the results as follows:***-theoretic entropy is the limit of measure-theoretic r-entropy and topological entropy is the limit of topological r-entropy(r → 0);*** r-entropy is more than or equal to the supremum of 4r-entropy in the sense of Feldman's definition,where the measure varies among all the ergodic Borel probability measures.

关键词： topological r-entropy measure-theoretic r-entropy

Influences of Ca and Y Addition on the Microstructure and Corrosion Resistance of Vacuum Die-Cast AZ91 Alloy

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Acta Metallurgica Sinica(English Letters) 2014年第4期27卷 609-614页

作者： Feng Wang Jibao Li Jing Liu Dan lv Pingli Mao zheng Liu School of Material Science and Engineering Shenyang University of Technology School of Science Shenyang University of Technology

The influences of Ca and Y additions on the microstructure and corrosion resistance of vacuum die-cast AZ91 alloys were investigated by optical microscope,electron scanning microscope,weight-loss test,and electrochemical corrosion *** results indicate that the Ca or Ca and Y additions refined the microstructure and decreased the amount of Mg17Al12 phase on grain boundaries in the ***,the addition of Ca and Y led to the formation of network Al2 Ca phase and rod-like Al2 Y phase,improved the corrosion resistance of AZ91 magnesium *** with AZ91 alloy,the corrosion rate of AZ91–1.5Ca–1.0Y alloy was decreased to 16.2%,and its corrosion current density was dropped by one order of magnitude after immersion in 3.5 wt% NaCl solution for 24 h.

关键词： AZ91 alloy Ca and Y Corrosion resistance Microstructure Polarization curve

Characterization of extracellular polymeric substances in the biofilms of typical bacteria by the sulfur K-edge XANES spectroscopy

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Journal of Environmental Sciences 2014年第8期26卷 1763-1768页

作者： Huirong Lin Chengsong Ye Lu lv Clark Renjun zheng Shenghua Zhang Lei zheng Yidong Zhao Xin Yu Institute of Urban Environment Chinese Academy of Science Beijing No.4 High School Institute of High Energy Physics Chinese Academy of ScienceBeijing Synchrotron Radiation Facility

A combined approach of physicochemical extraction and sulfur K-edge X-ray absorption near-edge structure（XANES） spectroscopy was applied to characterize the extracellular polymeric substances（EPS） of typical bacterial biofilms in this study. Physicochemical analysis showed variation of the contents of DNA,polysaccharide and protein in different fractions of EPS in different mediums. The sulfur K-edge XANES analysis yielded a variety of *** fitting of the XANES spectra utilizing a large set of model compounds showed that there was more reduced sulfur in both LB-EPS（loosely bound EPS） and TB-EPS（tightly bound EPS） of all the biofilms in LB medium than in R2 A medium. More oxidized sulfur was identified in LB-EPS than that in TB-EPS,suggesting different niches and physiological heterogeneity in the biofilms. Our results suggested that the sulfur K-edge XANES can be a useful tool to analyze the sulfur speciation in EPS of biofilms.

关键词： Biofilms Characterization EPS Sulfur XANES

Writing with a nano-grooved pin

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Science China(Technological Sciences) 2019年第9期62卷 1649-1654页

作者： DONG HuaLai YANG Xing lv CunJing WANG Jin zheng QuanShui State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China Center for Nano and Micro Mechanics Tsinghua UniversityBeijing 100084China Department of Engineering Mechanics Tsinghua UniversityBeijing 100084China

As a basic technology, dispensing liquid into small droplets is widely used in many nowadays technologies, such as 3D printing [I-4], biological/chemical patterning [5-7], and drug discovery [8,9]. Traditional transfer methods by pipette or pin, which may date to 4000 years ago [10], are simple and cheap to generate droplets bigger than μ100 pm [11] for most materials.

关键词： technology droplets materials

Fog-IBDIS:Industrial Big Data Integration and Sharing with Fog Computing for Manufacturing Systems

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Engineering 2019年第4期5卷 662-670页

作者： Junliang Wang Peng zheng Youlong lv Jingsong Bao Jie Zhang College of Mechanical Engineering Donghua UniversityShanghai 201620China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Industrial big data integration and sharing(IBDIS)is of great significance in managing and providing data for big data analysis in manufacturing systems.A novel fog-computing-based IBDIS approach called Fog-IBDIS is proposed in order to integrate and share industrial big data with high raw data security and low network traffic loads by moving the integration task from the cloud to the edge of ***,a task flow graph(TFG)is designed to model the data analysis *** TFG is composed of several tasks,which are executed by the data owners through the Fog-IBDIS platform in order to protect raw data ***,the function of Fog-IBDIS to enable data integration and sharing is presented in five modules:TFG management,compilation and running control,the data integration model,the basic algorithm library,and the management ***,a case study is presented to illustrate the implementation of Fog-IBDIS,which ensures raw data security by deploying the analysis tasks executed by the data generators,and eases the network traffic load by greatly reducing the volume of transmitted data.

关键词： Fog computing Industrial big data Integration Manufacturing system

Maximum Inner Product Method for Extracting the Path-Loss Parameters in Primary Transformer Substations

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China Communications 2019年第4期16卷 120-129页

作者： Qiang Li Hongxin Zhang Tianyi zheng Xueli Wang Yinghua lv School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Key Laboratory of Work Safety Intelligent Monitoring Beijing 100876China School of Sciences Beijing University of Posts and TelecommunicationsBeijing 100876China

In order to deploy short-range wireless communication devices in the primary transformer substation, a Maximum Inner Product(MIP) Method is proposed to extract the path-loss parameters in 110 kV and 220 kV primary transformer substations. The maximum inner product of the testing data is calculated to find out the loss index n and the standard deviation σ, and then the pathloss models can be set up. By comparing the MIP with Minimum Mean Square estimation(MMSE) and Cumulative Sum(CUSUM), MIP can match the measured values best. In order to apply the MIP path-loss model, under the initial signal to noise ratio(SNR) at 5 dB and 10 dB, a ZigBee simulation system is constructed to validate the situation that bit error rate(BER) varies with distance. And the ZigBee devices with 5 units are tested in a 220 kV primary transformer substation. The result of the test proves that the path-loss model is accurate.

关键词： primary transformer substation path-loss ZigBee