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Monte Carlo simulation of the electromagnetic wave propagation in the duststorm

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Science China(Physics,Mechanics & Astronomy) 2008年第8期51卷 1001-1009页

作者： gao zhiwen ZHOU YouHe ZHENG XiaoJing Key Laboratory of Mechanics on Western Disaster and Environment Ministry of EducationDepartment of MechanicsLanzhou UniversityLanzhou 730000China

Monte Carlo simulations of the extinction rate of electromagnetic wave propagation in the duststorm were presented. The numerical procedure was based on the multiple scattering and independent scattering. The calculated multiple scattering attenuation rate is in good agreement with the measured one,but differs significantly from those obtained under the independent scattering assumption. At the same time,the factors of size parameter,frequency of incident wave,the angle of incident,and sands permittivity and water content have been considered in the attenuation of electromagnetic wave propagation in the duststorm. Numerical results obtained showed that the attenuation rate increases as the fractional volume,frequency of incident wave and sands permittivity increase,and as the angle of incident increases,the attenuation rate decreases.

关键词： Monte Carlo simulation electromagnetic wave duststorm multiple-scattering independent scattering attenuation rate

高质量发展下关中平原城市群数字基础设施发展水平时空演化及其影响因素

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科学与管理 2024年第3期44卷 87-94页

作者：宋金昭高志文西安建筑科技大学管理学院陕西西安710055

实现数字基础设施均衡发展是高质量发展背景下关中平原城市群需要重点关注的问题之一。基于2012—2021年关中平原城市群11个城市的样本数据,采用标准差椭圆、空间马尔可夫链和灰色关联分析探究了数字基础设施发展水平的时空演化特征及... 详细信息

实现数字基础设施均衡发展是高质量发展背景下关中平原城市群需要重点关注的问题之一。基于2012—2021年关中平原城市群11个城市的样本数据,采用标准差椭圆、空间马尔可夫链和灰色关联分析探究了数字基础设施发展水平的时空演化特征及其影响因素。研究发现:关中平原城市群的数字基础设施发展水平并不均衡,但各城市之间的差距呈现逐渐缩小的趋势;空间格局总体呈现出东北-西南方向向心集聚、西北-东南方向空间发散的态势,分布重心逐渐向东移动;同时,在不同邻域类型下,各城市数字基础设施发展水平维持稳定的概率要高于向上或向下转移的概率,难以实现跨水平发展;政府支持力和内源拉动力对关中平原城市群数字基础设施发展水平的时空演化具有显著影响。通过考察关中平原城市群数字基础设施发展水平的时空格局演化及其影响因素,希冀为其优化布局和协调发展提供决策参考。

关键词：关中平原城市群数字基础设施高质量发展时空演化影响因素

维普期刊数据库博看期刊

APPLIED RESEARCH ON NEW MULTI-FUNCTION GASOLINE ADDITIVE

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Chinese Journal of Mechanical Engineering 2006年第4期19卷 626-632页

作者： CAI Ruibin MING Caibing gao zhiwen College of Automotive Engineering South China University of Technology Guangdong 510640 China Guangdong Key Laboratory for Electric Vehicle Research Guangdong 510640 China CNPC Lanzhou Petroleum ＆ Chemical Corperation Lanzhou 730060 China

In order to assess the performance of a new cleansing and combustion-improving gasoline additive （MAZ）, and to explore the evaluation methods of additives, two engines with the same model number and performance indices, fueled with and without the MAZ gasoline additive respectively, are carried through 100 h strenuous tests on a bench. The results obtained in full load characteristic and load characteristics of different operational modes are compared. It indicates that the power, economy and emission of the engine fueled with the MAZ additive all have obvious improvement in comparison with the engine without adding the additive： the power increasing by 16.43%, specific fuel consumption （SFC） decreasing 5.39%, and the emission of CO, HC and NOx falling by 28.61%, 54.38% and 10.1% respectively. Wear and tear of the engine cylinder is weakened, and sediment of combustion chamber inner side is reduced. In addition, no negative effect on the catalytic conversion device is found.

关键词： Gasoline additives Strenuous tests Energy-saving Exhaust emission

Analysis and side peaks identification of Chinese DTTB signal ambiguity functions for passive radar

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Science in China(Series F) 2009年第8期52卷 1409-1417页

作者： gao zhiwen TAO Ran WANG Yue Department of Electronic Engineering Beijing Institute of Technology Beijing 100081 China Beijing Aeronautical Technology Research Center Beijing 100076 China

Passive radar is one of the current research focuses. The implementation of the Chinese standard digital television terrestrial broadcasting （DTTB） creates a new opportunity for passive radar. DTTB system contains single-carrier and multicarrier application modes. In this paper, ambiguity functions of the D＇I-I＇B signals in the single-carrier and multicarrier application modes are analyzed. Ambiguity function of the DTTB signal contains one main peak and many side peaks. The relative positions and amplitudes of the side peaks are derived and the reasons for the occurrence of the side peaks are obtained. The side peaks identification （SPI） algorithm is proposed for avoiding the false alarms caused by the side peaks. Experimental results show that the SPI algorithm can indentify all the side peaks without the power loss. This research provides the foundation for designing the DTTB based passive radar.

关键词： passive radar DI-FB ambiguity function side peaks identification

Eu^2＋-doped Sr5(PO4)3Br blue-emitting phosphor with high color purity for near-UV-pumped white light-emitting diodes

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Journal of Rare Earths 2018年第9期36卷 917-923页

作者： zhiwen gao Shihua Liu Pengfei Sun Jung Hyun Jeong Ruijin Yu Bin Deng College of Chemistry and Pharmacy Northwest A&F University Yangling 712100 China College of Chemical Biological and Environmental Engineering Xiangnan University Chenzhou 423043 China Department of Physics Pukyong National University Busan 608-737 Republic of Korea

Eu2＋-doped bromophosphateapatite Sr5（PO4）3 Br phosphors were synthesized by the conventional hightemperature solid-state *** crystal structure and luminescence properties of the phosphors,as well as their thermal stability and CIE chromaticity coordinates were systematically *** spectra of Sr5（PO4）3 Br：Eu2＋ exhibit a single blue emission at 450 nm under the excitation of 345 nm,which is ascribed to the 4 f-5 d transition of Eu2＋.The phosphor shows very good thermal stability; The CIE color coordinates are very close to those of BaMgAl10O17：Eu2＋（BAM）.All the properties indicate that the blue-emitting Sr5（PO4）3 Br：Eu2＋ phosphor has potential application in white LEDs.

关键词： Bromophosphate Luminescence EU^2 + ion Rare earths

Effects of interfacial discontinuity on the fracture behavior in the superconductor-substrate system

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Theoretical & Applied Mechanics Letters 2019年第1期9卷 43-49,I0004页

作者： Lang Jiang Xiaoqiang Ren zhiwen gao Youhe Zhou Key Laboratory of Mechanics on Disaster and Environment in Western China attached to the Ministry of Education of China Lanzhou University Department of Mechanics and Engineering Science College of Civil Engineering and Mechanics Lanzhou University

This study concerns a two-dimensional model and the corresponding virtual crack closure technique(VCCT) implemented to solve the general boundary value problems that may explain why interface discontinuity has effects on the fracture behavior in the superconductor-substrate system. The interfacial discontinuity can be classified according to the material properties' continuity and their derivatives' continuity at the interface. For nonhomogeneous superconductor and substrate specimens with various material properties, a VCCT method is developed to calculate their fracture behavior. Furthermore, the effects of applied magnetic field amplitude and nonhomogeneous parameters are extensively and parametrically studied in two activation processes(zero-field cooling and field cooling). The integrative and computational study presented here provide a fundamental mechanistic understanding of the fracture mechanism in the superconductor-substrate system and sheds light on the rational design of interfacial continuity.

关键词： Superconductor-substrate system Interfacial discontinuity Fracture behavior Activation processes

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基于数据驱动的电动汽车动力电池SOC预测

汽车工程 2021年第1期43卷 1-9,18页

作者：胡杰高志文武汉理工大学现代汽车零部件技术湖北省重点实验室武汉430070 武汉理工大学汽车零部件技术湖北省协同创新中心武汉430070 新能源与智能网联车湖北工程技术研究中心武汉430070

为准确预测电动汽车动力电池的能耗,缓解驾驶者的里程焦虑,本文中提出一种基于数据驱动的电动汽车动力电池SOC预测模型。首先分析电动汽车能耗构成并提取能耗影响因素,接着基于某款电动出租车CAN总线采集的汽车运行数据,采用机器学习算... 详细信息

为准确预测电动汽车动力电池的能耗,缓解驾驶者的里程焦虑,本文中提出一种基于数据驱动的电动汽车动力电池SOC预测模型。首先分析电动汽车能耗构成并提取能耗影响因素,接着基于某款电动出租车CAN总线采集的汽车运行数据,采用机器学习算法,提出基于温度分层的能耗模型,通过宏观数据与微观数据的融合减小误差,最后使用该模型对车载BMS提供的SOC数据进行对比验证。结果表明,该模型预测效果较好,为帮助优化电动汽车能量控制策略、缓解里程焦虑提供科学的决策支持。

关键词：电动汽车 SOC预测数据驱动机器学习

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奥氮平治疗阿尔茨海默病的效果分析

中国社区医师 2024年第15期40卷 11-13页

作者：李高粉陆永明高志文吴晓亮张俊杰汪晨阳蒙城脑康医院安徽亳州233500

目的:分析奥氮平治疗阿尔茨海默病的效果。方法:选取2020年8月—2022年8月蒙城脑康医院收治的阿尔茨海默病患者82例作为研究对象,随机分为研究组与对照组,各41例。对照组给予利培酮治疗,研究组给予奥氮平治疗。比较两组治疗效果。结果:... 详细信息

目的:分析奥氮平治疗阿尔茨海默病的效果。方法:选取2020年8月—2022年8月蒙城脑康医院收治的阿尔茨海默病患者82例作为研究对象,随机分为研究组与对照组,各41例。对照组给予利培酮治疗,研究组给予奥氮平治疗。比较两组治疗效果。结果:治疗后1个月,两组阿尔茨海默病病理行为评定量表(BEHAVE-AD)评分低于治疗前,且研究组低于对照组,差异有统计学意义(P0.05)。研究组不良反应总发生率低于对照组,差异有统计学意义(P=0.034)。结论:奥氮平治疗阿尔茨海默病的效果显著,能够改善患者行为功能,降低不良反应发生率,值得临床应用并予以推广。

关键词：奥氮平利培酮阿尔茨海默病精神行为障碍

Fabrication of MXene-Bi_(2)WO_(6)heterojunction by Bi_(2)Ti_(2)O_(7)hinge for extraordinary LED-light-driven photocatalytic performance

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Nano Research 2024年第6期17卷 4729-4736页

作者： zhiwen Li Liangliang Xu Zaheer Ud Din Babar Ali Raza Yifei Zhang Xinrui Gu Yu-Xin Miao Zhen Zhao gao Li Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang 110034China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Scuola Superiore Meridionale(SSM) University of Naples Federico IILargo S.Marcellino1080138Italy Department of Chemical and Biomolecular Engineering Korea Advanced Institute of Science and Technology(KAIST)Daejeon 34141Republic of Korea University of Chinese Academy of Sciences Beijing 100049China

Heterojunction composites with intimate interfaces can shorten the diffusion distance,which leads to a shorter path for photogenerated carriers,thereby increasing photocatalytic ***,we report the fabrication of Ti_(3)C_(2)-Bi_(2)WO_(6)(TC-BW)heterojunctions hinged by Bi_(2)Ti_(2)O_(7)joints via an in situ hydrothermal reaction of Ti_(3)C_(2)in the presence of Na_(2)WO_(4)and Bi(NO_(3))_(3).The TC-BW was characterized using X-ray diffraction(XRD),scanning transmission electron microscopy(STEM),and Raman ***-BW showed superior photocatalytic activity(productivity over 15TC-WB reaches up to 5.0 mmolreacted BA·gcat.^(−1)·h^(−1))in the oxidation of benzyl alcohol using light-emitting diode(LED)light,arising from the surface defects and intimate heterojunction interface between the Ti_(3)C_(2)MXene and Bi_(2)WO_(6)***-BW heterojunctions provide an enhanced separation efficiency of photogenerated charges,which in turn yields superior photocatalytic ***,it is well substantiated by density functional theory(DFT)*** summary,this study elucidates the preparation of heterojunction composites with intimate interfaces for highly efficient photooxidation.

关键词： MXene-Bi_(2)WO_(6) heterojunction LED-light-driven photocatalysis Bi_(2)Ti_(2)O_(7) photooxidation