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《北洋官报》所载广告问题探析

河北广播电视大学学报 2016年第6期21卷 9-13页

作者：翟砚辉裴泽宇北京交通大学海滨学院河北沧州061199

广告是《北洋官报》刊登的重要内容,对其进行专题研究,具有重要意义。《北洋官报》的广告业务,拥有较为先进的技术条件,采用现代经营理念,运用"图片、注意消费者心理"等方式刊载了涉及"金融类、商业类、文教类、工业类、交通类、社会类... 详细信息

广告是《北洋官报》刊登的重要内容,对其进行专题研究,具有重要意义。《北洋官报》的广告业务,拥有较为先进的技术条件,采用现代经营理念,运用"图片、注意消费者心理"等方式刊载了涉及"金融类、商业类、文教类、工业类、交通类、社会类"的大量广告,曾取得了不错的效果。《北洋官报》广告呈现出近代色彩,具有进步意义,但后期经营却逐渐下滑。

关键词：《北洋官报》广告业务经营内容特点

青藏高原3种风毛菊属植物的繁殖分配与海拔高度的相关性

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植物生态学报 2012年第1期36卷 39-46页

作者：王一峰刘启茜裴泽宇李海燕西北师范大学生命科学学院兰州730070

对产于青藏高原东缘的风毛菊属植物柳叶菜风毛菊(Saussurea epilobioides)、尖苞风毛菊(***)和钝苞雪莲(***)的30个居群的繁殖分配及其与海拔间的相关性进行了初步研究。通过采样调查法和烘干重量法,检测了不同海拔3种风毛菊属植物的繁... 详细信息

对产于青藏高原东缘的风毛菊属植物柳叶菜风毛菊(Saussurea epilobioides)、尖苞风毛菊(***)和钝苞雪莲(***)的30个居群的繁殖分配及其与海拔间的相关性进行了初步研究。通过采样调查法和烘干重量法,检测了不同海拔3种风毛菊属植物的繁殖分配。结果显示:1)海拔与植株个体大小呈负相关关系;2)海拔与繁殖分配呈正相关关系,将个体大小作为协变量,去除其影响,海拔与繁殖分配仍呈正相关关系;3)个体大小与繁殖分配呈负相关关系,将海拔作为协变量,去除其影响,个体大小和繁殖分配的相关性消失。研究表明,海拔作为外界因子对繁殖分配有显著的影响,这种影响不依赖于植物的内部因素(如个体大小的差异)。

关键词：海拔相关性个体大小繁殖分配风毛菊属

Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： Feng Zhang Chenyang Zhang Linlin Wu Wei Sun Hongliang Zhang Jianhua Chen Yong pei Songjiang Li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway Resource Group Co.Ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

Micro defects formation and dynamic response analysis of steel plate of quasi-cracking area subjected to explosive load

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Defence Technology（防务技术） 2024年第1期31卷 580-593页

作者： Zheng-qing Zhou ze-chen Du Xiao Wang Hui-ling Jiang Qiang Zhou yu-long Zhang yu-zhe Liu pei-ze Zhang Research Institute of Macro-Safety Science University of Science and TechnologyBeijing100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China School of Mechanical Engineering Nantong UniversityNantong226019China China North Industry Advanced Technology Generalization Institute Beijing100089China China Academy of Ordnance Science China

As the protective component,steel plate had attracted extensive attention because of frequently threats of explosive *** this paper,the evolution of microstructure and the mechanism of damage in the quasi-cracking area of steel plate subjected to explosive load were discussed and the relationships between micro defects and dynamic mechanical response were *** the explosion experiment,five observation points were selected equidistant from the quasi-cracking area of the section of the steel plate along the thickness direction,and the characteristics of micro defects at the observation points were analyzed by optical microscope(OM),scanning electron microscope(SEM) and electron backscattered diffraction(EBSD).The observation result shows that many slip bands(SBs) appeared,and the grain orientation changed obviously in the steel plate,the two were the main damage types of micro *** addition,cracks,peeling pits,grooves and other lager micro defects were appeared in the lower area of the *** stress parameters of the observation points were obtained through an effective numerical *** mechanism of damage generation and crack propagation in the quasicracking area were clarified by comparing the specific impulse of each observation point with the corresponding micro *** result shows that the generation and expansion of micro defects are related to the stress area(*** upper compression area,the neutral plane area,and the lower tension area).The micro defects gather and expand at the grain boundary,and will become macroscopic damage under the continuous action of tensile ***,the micro defects at the midpoint of the section of the steel plate in the direction away from the explosion center(*** horizontal direction) were also *** was found that the specific impulse at these positions were much smaller than that in the thickness direction,the micro defects were only SBs and a few micro cracks,and the those decrea

关键词： Explosive load Quasi-cracking area Micro defects Steel plate Dynamic response Numerical simulation

Friction and Wear Behaviors of MoS_2/Zr Coated HSS in Sliding Wear and in Drilling Processes

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Chinese Journal of Mechanical Engineering 2012年第6期25卷 1218-1223页

作者： DENG Jianxin YAN pei WU ze Department of Mechanical Engineering Shandong UniversityJinan 250061China

MoS2 metal composite coatings have been successful used in dry turning, but its suitability for dry drilling has not been yet established. Therefore, it is necessary to study the friction and wear behaviors of MoS2/Zr coated HSS in sliding wear and in drilling processes. In the present study, MoS2/Zr composite coatings are deposited on the surface of W6Mo5Cr4V2 high speed steel（HSS）. Microstructural and fundamental properties of these coatings are examined. Ball-on-disc sliding wear tests on the coated discs are carried out, and the drilling performance of the coated drills is tested. Test results show that the MoS2/Zr composite coatings exhibit decreases friction coefficient to that of the uncoated HSS in sliding wear tests. Energy dispersive X-ray（EDX） analysis on the wear surface indicates that there is a transfer layer formed on the counterpart ball during sliding wear processes, which contributes to the decreasing of the friction coefficient between the sliding couple. Drilling tests indicate that the MoS2/Zr coated drills show better cutting performance compared to the uncoated HSS drills, coating delamination and abrasive are found to be the main flank and rake wear mode of the coated drills. The proposed research founds the base of the application of MoS2 metal composite coatings on dry drilling.

关键词： cutting tools coating MoS2 wear mechanisms

Synthesis and Characterization of Microcapsules with Chlorpyrifos Cores and Polyurea Walls

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Chemical Research in Chinese Universities 2006年第3期22卷 379-382页

作者： ZHANG Qiang ZHANG pei-pei JIAO Qing-ze College of Science Beijing Institute of Technology Beijing 100081 P. R. China College of Chemistry and Environmental Science Beijing Institute of Technology Beijing 100081 P. R. China

Microcapsules with chlorpyrifos cores and polyurea walls were synthesized with 2,4-tolylene diisocyanate as an oil-soluble monomer and ethylenediamine as a water-soluble monomer via an interracial polycondensation reaction. The products were characterized by means of Fourier transform infrared spectrometry, ^13C NMR spectrometry and ^31p NMR spectrometry. The morphology, the particle size and the particle size distribution, and the thermal properties were also evaluated. The prepared microcapsules exhibit clear and smooth surfaces and have a mean diameter of 28. 13 μm. These microcapsules also have a good thermal stability for long-term use, and have potential applications in minimizing the toxicity of chlorpyrifos through controlled release.

关键词： Microcapsule Chlorpyrifos Polyurea Synthesis Characterization

基于4G技术的工程结构无线振动测试系统节点设计

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太原学院学报（自然科学版） 2025年第1期43卷 38-46页

作者：秦乐余沛信阳学院土木工程学院河南信阳464000

结构振动测试是大型土木工程结构健康监测的有效保障,传统振动测试存在布线困难、低频率信号拾取困难、通信速率底、易受到测试现场条件限制等问题。以4G技术为研究对象,提出了一种基于4G技术的工程结构无线振动测试系统节点设计方案,... 详细信息

结构振动测试是大型土木工程结构健康监测的有效保障,传统振动测试存在布线困难、低频率信号拾取困难、通信速率底、易受到测试现场条件限制等问题。以4G技术为研究对象,提出了一种基于4G技术的工程结构无线振动测试系统节点设计方案,通过节点工作原理介绍及各个模块的功能特性分析,研究了标准振动台性能对比测试和基于有线及无线的结构振动对比试验。结果表明:节点传感器的线性度误差为0.29%,且在短距离以及超远距离测试条件下,试验结构的各阶频率测试结果均与有线加速度传感器的测试结果一致,表明节点在测试精度和数据高速率传输等方面具有较大优势,解决了中远及超远距离中工程数据传输问题,具有一定的工程实用性,在土木工程健康监测和工程强震观测领域具有广泛的应用前景。

关键词： 4G通信技术无线振动测试节点灵敏度脉动自由衰减

Natural Convective Heat and Mass Transfer of Water with Corrosion Products at Super-Critical Pressures under Cooling Conditions

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Journal of Thermal Science 1993年第1期2卷 25-31页

作者： pei－XueJiang ze－peiRen 等 DepartmentofThermalEngineering TsinghuaUniversityBeijing100084China DepartmentofThermalEngineering

A numerical study is reported of laminar natural convective heat and mass transfer on a vertical cooled plate for water containing metal corrosion products at super-critical pressures. The influence of variable properties at super-critical pressures on natural convection has been analyzed. The difference between heat and mass transfer under cooling or heating conditions is also discussed and some correlations for heat and mass transfer under cooling conditions are recommended.

关键词： natural convection heat and mass transfer super-critical pressures cooling conditions metallic corrosion products.

Spherical lanthanide nanoclusters toward white-light emission and cell membrane imaging

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Nano Research 2023年第8期16卷 11495-11502页

作者： Hai-Ling Wang Zhiqiang Ni ze-yu Ruan Zhong-Hong Zhu pei-yu Liao Guangxue Feng Jian-Hua Jia Ming-Liang Tong Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-Sen UniversityGuangzhou 510006China State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular AggregatesSchool of Materials Science and EngineeringSouth China University of TechnologyGuangzhou 510640China

Lanthanide doping is an effective strategy for modulating the emission of ***,by changing the cluster composition to control the energy transfer pathway,the application potential of high-nuclearity lanthanide cluster(HLC)as white-light emitter has been confirmed for the first ***,by precisely controlling the proportion of GdIII,TbIII,and EuIII ions in reactants,we obtained a spherical heterotrimetallic nanocluster Gd_(10)Tb_(12)Eu_(10),a white-light emitter with quantum yield(QY)of 12.58%and lifetime of 327.14μ***-resolution electrospray ionization mass spectrometry(HRESI-MS)demonstrates that homometallic nanoclusters Ln_(32)(Ln=Gd,Tb,and Eu)are tetracationic clusters and are highly stable in *** peripheral dense organic ligands provide a protective layer for the cluster core,which improves the stability of Ln_(32) in aqueous solution,avoids the contact between metal centers and bioactive molecules,and greatly reduces the biological *** cell imaging experiments,cationic clusters Ln_(32) are mainly localized on the cell membrane with negative charge *** far as we know,this is the first time that spherical lanthanide nanoclusters have been used for membrane imaging of living cell,opening the door for the application of HLCs in biological imaging.

关键词： spherical lanthanide clusters white-light emission high stability low toxicity cell membrane imaging