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Journal of Environmental Sciences 2023年第4期126卷 794-805页

作者： Yunhua Zhang Diming lou Piqiang Tan Zhiyuan Hu liang Fang School of Automotive studies Tongji UniversityShanghai 201804China

In this study, the effects of a diesel oxidation catalyst(DOC) coupled with a catalyzed diesel particulate filter(CDPF) with different catalyst loadings on the power, fuel consumption,gaseous and particulate emissions from a non-road diesel engine were investigated. Results showed that the after-treatment had a negligible effect on the power and fuel *** reduction effect of the DOC on the CO and hydrocarbon(HC) increased with the engine load. Further reductions occurred coupling with the CDPF. Increasing the catalyst loading resulted in a more significant reduction in the HC emissions than CO emissions. The DOC could increase the NO_(2)proportion to 37.9%, and more NO_(2)was produced when coupled with the CDPF below 250℃;above 250℃, more NO_(2)was consumed. The after-treatment could reduce more than 99% of the particle number(PN) and 98% of the particle mass(PM).Further reductions in the PN and PM occurred with a higher CDPF catalyst loading. The DOC had a better reduction effect on the nucleation particles than the accumulation ones, but the trend reversed with the CDPF. The DOC shifted the particle size distribution(PSD) to larger particles with an accumulation particle proportion increasing from 13% to 20%, and the geometric mean diameter(GMD) increased from 18.2 to 26.0 nm. The trend reversed with the CDPF and the accumulation particle proportion declined to less than 10%. A lower catalyst loading on the CDPF led to a higher proportion of nucleation particles and a smaller GMD.

关键词： Catalyzed diesel particulate filter Catalyst loading Emissions Particle size distribution Geometric mean diameter

ISO 20340:2009老化试验操作要点及注意事项

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现代涂料与涂装 2017年第3期20卷 28-31页

作者：徐翠竹那骥宇娄亮杰韩冰中国石油集团工程技术研究院天津300451

为保证新建海上平台及相关结构使用寿命,所采用的涂料体系性能满足防护要求,国际标准ISO 20340:2009采用老化试验的方法,对应用于腐蚀环境C5-M(海洋大气腐蚀环境)的涂层体系进行资格认定测试。从实验室检测需要出发,提出了老化试验的操... 详细信息

为保证新建海上平台及相关结构使用寿命,所采用的涂料体系性能满足防护要求,国际标准ISO 20340:2009采用老化试验的方法,对应用于腐蚀环境C5-M(海洋大气腐蚀环境)的涂层体系进行资格认定测试。从实验室检测需要出发,提出了老化试验的操作要点和注意事项。

关键词： ISO 20340: 2009 涂层腐蚀老化试验盐雾试验

Secret Key Generation Based on Two-Way Randomness for TDD-SISO System

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China Communications 2018年第7期15卷 202-216页

作者： Shengjun Zhang liang Jin Yangming lou Zhou Zhong National Digital Switching System Engineering&Technological Research Center Zhengzhou 450002China

A novel secret key generation(SKG)method based on two-way randomness is proposed for TDD-SISO *** legitimate transceivers mutually transmit their own random signal via reciprocal wireless channel,then the multiplication of transmitted and received signal is used as common randomness to generate secret *** quasi-static channel,the theoretical SKG rates(SKGRs)of the three SKG methods,namely wireless channel based,one-way randomness and two-way randomness,are derived and ***,two practical SKG schemes based on twoway randomness,Scheme-1bit and Scheme-3bit,are completely designed and ***,Scheme-1bit applies to low signal to noise ratio(SNR)scenarios and achieves 0.13~0.86bit/T_s SKGR and 10^(-2)~10^(-5) level secret key outage probability(SKOP),while Scheme-3bit fits high SNR situation and obtains 0.93~1.35bit/T_s SKGR and 10^(-3)~10^(-4) level *** last,the national institute of standards and technology(NIST)test is conducted to evaluate the secret key randomness(SKRD)and the test results show that both of the proposed schemes have passed the test.

关键词： secret key generation physical layer security information reconciliation information theory

Multi-stream signals separation based on space-time-isomeric (SPATIO) array using metasurface antennas

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Science China(Information Sciences) 2024年第2期67卷 181-200页

作者： Yangming lou liang JIN Huiming WANG Zhou ZHONG Junyan DAI PLA Strategic Support Force Information Engineering University School of Information and Communications Engineering Xi'an Jiaotong University 3. State Key Laboratory of Millimeter WavesSoutheast University

In spatial domain signal processing, it is necessary to equip more antennas at the receiver to improve spatial demultiplexing capability. However, increasing the number of antennas under restricted space will reduce antenna spacing and raise the channel correlation, making the number of signal streams spatially demultiplexed much smaller than that of antennas. This paper proposes a method to design a space-timeisomeric(SPATIO) array based on metasurface antennas under wireless multipath conditions. Each antenna in this array has a different pattern and varies independently with time, reducing the channel correlation by superposing multipath at distinct positions and moments. Based on the SPATIO array, we present an array parameter design scheme based on infinity norm minimization, which can maximize the received energy of each stream while separating multi-stream received signals. Simulation results illustrate the performance of the SPATIO array for multi-stream signal reception. Compared with conventional multiple-input multipleoutput arrays, the proposed array can reduce the bit error rate by one order of magnitude under the same simulation conditions.

关键词： multiple-input multiple-output metasurface antenna space-time-isomeric array multipath channel degree of freedom

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创伤性膈疝24例临床分析

临床军医杂志 2012年第3期40卷 619-620页

作者：楼良潮陆文博张勇解放军第113医院胸外科浙江宁波315040

目的探讨创伤性膈疝的诊断及治疗方法。方法回顾性分析24例创伤性膈疝患者的致伤原因及诊断、治疗过程。结果 24例创伤性膈疝患者均行手术治疗,治愈22例,死亡2例,治愈率91.7%。结论对胸腹部创伤患者详细询问受伤情况,全面体格检查,根据... 详细信息

目的探讨创伤性膈疝的诊断及治疗方法。方法回顾性分析24例创伤性膈疝患者的致伤原因及诊断、治疗过程。结果 24例创伤性膈疝患者均行手术治疗,治愈22例,死亡2例,治愈率91.7%。结论对胸腹部创伤患者详细询问受伤情况,全面体格检查,根据X线、CT和临床特点多能得到早期诊断,及时手术治疗是提高治愈率的关键。

关键词：创伤性膈疝膈肌破裂修复手术

Temperature Variable Optimization for Precision Machine Tool Thermal Error Compensation on Optimal Threshold

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Chinese Journal of Mechanical Engineering 2013年第1期26卷 158-165页

作者： ZHANG Ting YE Wenhua liang Ruijun lou Peihuang YANG Xiaolan College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics School of Mechanical Engineering Nanjing Institute of Technology

Machine tool thermal error is an important reason for poor machining accuracy. Thermal error compensation is a primary technology in accuracy control. To build thermal error model, temperature variables are needed to be divided into several groups on an appropriate threshold. Currently, group threshold value is mainly determined by researchers experience. Few studies focus on group threshold in temperature variable grouping. Since the threshold is important in error compensation, this paper arms to find out an optimal threshold to realize temperature variable optimization in thermal error modeling. Firstly, correlation coefficient is used to express membership grade of temperature variables, and the theory of fuzzy transitive closure is applied to obtain relational matrix of temperature variables. Concepts as compact degree and separable degree are introduced. Then evaluation model of temperature variable clustering is built. The optimal threshold and the best temperature variable clustering can be obtained by setting the maximum value of evaluation model as the objective. Finally, correlation coefficients between temperature variables and thermal error are calculated in order to find out optimum temperature variables for thermal error modeling. An experiment is conducted on a precise horizontal machining center. In experiment, three displacement sensors are used to measure spindle thermal error and twenty-nine temperature sensors are utilized to detect the machining center temperature. Experimental result shows that the new method of temperature variable optimization on optimal threshold successfully worked out a best threshold value interval and chose seven temperature variables from twenty-nine temperature measuring points. The model residual of z direction is within 3 μm. Obviously, the proposed new variable optimization method has simple computing process and good modeling accuracy, which is quite fit for thermal error compensation.

关键词： precision machine tool thermal error cluster analysis

Four years of free-air CO_2 enrichment enhance soil C concentrations in a Chinese wheat field

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Journal of Environmental Sciences 2009年第9期21卷 1221-1224页

作者： ZHONG Shuang liang Wenju lou Yilai LI Qi ZHU Jianguo Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China. Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China

Elevated atmospheric CO2 can influence soil C dynamics in agroecosystems. The effects of free-air CO2 enrichment （FACE） and N fertilization on soil organic C （Corg）, dissolved organic C （DOC）, microbial biomass C （Cmic） and soil basal respiration （SBR） were investigated in a Chinese wheat field after expose to elevated CO2 for four full years. The results indicated that elevated CO2 has stimulative effects on soil C concentrations regardless of N fertilization. Following the elevated CO2, the concentrations of Corg and SBR were increased at wheat jointing stage, and those of DOC and Cmic were enhanced obviously across the wheat jointing stage and the fallow period after wheat harvest. On the other hand, N fertilization did not significantly affect the content of soil C. Significant correlations were found among DOC, Cmic, and SBR in this study.

关键词： dissolved organic C free air CO2 enrichment microbial biomass C N fertilization soil basal respiration soil organic C

Digital signal acquisition system for complex nuclear reaction experiments

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Nuclear Science and Techniques 2024年第1期35卷 124-133页

作者： Wei-liang Pu Yan-Lin Ye Jian-Ling lou Jia-Hao Chen School of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Institute of Applied Physics and Computational Mathematics Beijing 100094China

A digital data-acquisition system based on XIA LLC products was used in a complex nuclear reaction experiment using radioactive ion beams.A flexible trigger system based on a field-programmable gate array(FPGA)parametrization was developed to adapt to different experimental sizes.A user-friendly interface was implemented,which allows converting script language expressions into FPGA internal control *** proposed digital system can be combined with a conventional analog data acquisition system to provide more *** performance of the combined system was veri-fied using experimental data.

关键词： Digital signal acquisition system Trigger Programmable logic Timestamp

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星载合成孔径雷达的发展以及干涉测量应用

遥感信息 2006年第4期28卷 79-82页

作者：牛瑞汤晓涛楼良盛刘志铭王昱西安测绘研究所西安710054

论述了星载合成孔径雷达的发展历程,介绍了作为其重要应用之一的星载InSAR的概念和发展,详细介绍了典型的系统如欧空局的ERS-1/2星对、美国的SRTM任务、新近发射的日本ALOS卫星以及计划今年发射的德国的TerraSAR-X雷达卫星和加拿大的RAD... 详细信息

论述了星载合成孔径雷达的发展历程,介绍了作为其重要应用之一的星载InSAR的概念和发展,详细介绍了典型的系统如欧空局的ERS-1/2星对、美国的SRTM任务、新近发射的日本ALOS卫星以及计划今年发射的德国的TerraSAR-X雷达卫星和加拿大的RADARSAT-2雷达卫星。最后详述了星载InSAR未来的发展方向编队卫星技术以及国外重要的编队卫星计划如法国Cartwheel方案和德国TanDEM-X任务。

关键词：星载合成孔径雷达星载合成孔径雷达干涉测量编队卫星

Preparation of BiFeO_3 solution and its movement effects controlled by electrical field

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Rare Metals 2012年第5期31卷 507-511页

作者： lou Jianyong JIANG Xingsheng XU Tiejun liang Deliang JIAO Fangjun GAO Lin State Key Laboratory of Electrical Insulation and Power Equipment Xi 'an Jiaotong University Xi 'an 710049 China Xi'an Modern Control Technology Institute Xi'an 710065 China

This paper demonstrated our discovery of the movement effect of BiFeO_3 nanoparticles in solution by strong electrical polarization. First, BiFeO_3 nanoparticles were prepared by ball milling and characterized by SEM. Then, the preparation of BiFeO_3 solution was finished. BiFeO_3 nanoparticles are found to move in solution due to electrical field. The movement velocity of BiFeO_3 nanoparticles, which is about 10 μm·s^-1 , is influenced and controlled by the applied electrical field. The concentration of BiFeO_3 solution and the nanoparticle sizes also have effects on its movement properties. The movement of BiFeO_3 nanoparticles in solution is induced by strong polarization, and BiFeO_3 nanoparticles have net negative electric charges because of the electrostatic force between BiFeO_3 nanoparticles and the negative ions in water resolver.

关键词： BiFeO_3 solution movement property nanoparticle multi-ferroic material