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Science China(Technological Sciences) 2016年第7期59卷 1048-1053页

作者： WANG YunLi CAI Kai ma jingtao ZENG Fei GUO Dong Institute of Acoustics Chinese Academy of Sciences Beijing 100190 China Beijing Center for Physical and Chemical Analysis Beijing 100089 China School of materials Science & Engineering Tsinghua University Beijing 100084 China School of materials Science & Engineering Beihang University Beijing 100191 China

High performance piezoelectric ceramics with high Curie temperatures(TC) are the bottle necks of relevant high temperature devices. In this study, the electrical performance and microstructure of Li and Mn codoped Aurivillius-type composite ceramics with a composition Ca_(0.99-x_Bi_(6.99+x)(Li Mn)_(0.01) Nb Ti_5O_(24)(x = 0–0.8) were systematically investigated. The results indicated that uniform intergrowth structure with a lattice similar to that of the end member CBT could be formed at a low x value(x mance of the samples was found to be related to the density and larger lattice distortion along the polarization a axis. The results also demonstrated that formation of the compound system was an effective way in improving the performance of Aurivillius-type high TC piezoelectric ceramics.

关键词： piezoelectric ceramics Curie temperature ferroelectricity dielectric properties

A novel coated-particle design and fluidized-bed chemical vapor deposition preparation method for fuel-element identification in a nuclear reactor

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Particuology 2017年第2期15卷 35-41页

作者： Rongzheng Liu malin Liu Youlin Shao Xiaotong Chen jingtao ma Bing Liu Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy Technology Tsinghua University Beijing100084 China

Particle coating is an important method that can be used to expand particle-technology applications. Coated-particle design and preparation for nuclear fuel-element trajectory tracing were focused on in this paper. Particles that contain elemental cobalt were selected because of the characteristic gamma ray spectra of 60Co. A novel particle-structure design was proposed by coating particles that contain elemental cobalt with a high-density silicon-carbide （SiC） layer. During the coating process with the high-density SiC layer, cobalt metal was formed and diffused towards the coating, so an inner SiC–CoxSi layer was designed and obtained by fluidized-bed chemical vapor deposition coupled with in-situ chemical reaction. The coating layers were studied by X-ray diffractometry, scanning electron microscopy, and energy dispersive X-ray spectroscopy techniques. The chemical composition was also determined by inductively coupled plasma optical emission spectrometry. The novel particle design can reduce the formation of metallic cobalt and prevent cobalt diffusion in the coating process, which can maintain safety in a nuclear reactor for an extended period. The experimental results also validated that coated particles maintain their structural integrity at extremely high temperatures （～1950 °C）, which meets the requirements of next-generation nuclear reactors.

关键词： Particle coating Particle design Cobalt Pluidized-bed chemical vapor deposition Nuclear fuel

Deriving Operational Origin-Destination matrices From Large Scale Mobile Phone Data

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International Journal of Transportation Science and Technology 2013年第3期2卷 183-203页

作者： jingtao ma Huan Li Fang Yuan Thomas Bauer Mygistics Inc.9755 SW Barnes Rd.Ste 550PortlandORUSA Delaware Valley Regional Planning Council 190 N Independence Mall WestPhiladelphiaPA 19106USA

A method is presented in this work that integrates both emerging and mature data sources to estimate the operational travel demand in fine spatial and temporal *** analyzing individuals’mobility patterns revealed from their mobile phones,researchers and practitioners are now equipped to derive the largest trip samples for a *** of its ubiquitous use,extensive coverage of telecommunication services and high penetration rates,travel demand can be studied continuously in fine spatial and temporal *** derived sample or seed trip matrices are coupled with surveyed commute flow data and prevalent travel demand modeling techniques to provide estimates of the total regional travel demand in the form of origindestination(OD)*** methodology is evaluated in a series of real world transportation planning studies and proved its potentials in application areas such as dynamic traffic assignment modeling,integrated corridor management and online traffic simulations.

关键词： operational origin-destination matrix large scale mobile phone data matrix correction trip imputation path-matching travel demand projection

Fast and dynamic generation of linear octrees for geological bodies under hardware acceleration

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Science China Earth Sciences 2010年第1期53卷 113-119页

作者： DENG Hao ZHANG LiQiang maO XianCheng ma jingtao KANG ZhiZhong PENG JunHuan RUI XiaoPing LIU Liu State Key Laboratory of Remote Sensing Science Beijing Normal UniversityBeijing 100875China School of Geoscience and Environmental Engineering Central South UniversityChangsha 410083China PTV America Inc.1145 Broadway Plaza Ste 605TacomaWA 98407USA Department of Geodesy and Geomatics School of Land Science and TechnologyChina University of GeosciencesBeijing 100083China College of Resources and Environment Graduate University of Chinese Academy of SciencesBeijing 100049China

In the application of 3D Geoscience Modeling,we often need to generate the volumetric representations of geological bodies from their surface *** octree,as an efficient and easily operated volumetric model,is widely used in 3D Geoscience *** paper proposes an algorithm for fast and dynamic generation of linear octrees of geological bodies from their surface models under hardware *** Z-buffers are used to determine the attributes of octants and voxels in a fast way,and a divide-and-conquer strategy is adopted.A stack structure is exploited to record the subdivision,which allows generating linear octrees *** algorithm avoids large-scale sorting process and bypasses the compression in linear octrees *** results indicate its high efficiency in generating linear octrees for large-scale geologic bodies.

关键词： 3D Geoscience Modeling octree geological body hardware acceleration

British Education for White People:Educational Assimilation,Social Production,Genders,and Research Basis

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Psychology Research 2022年第3期12卷 122-128页

作者： ma jingtao University College London LondonThe United Kingdom

More and more UK-based researches begin to focus on the British White population,as they are the main ethic group in UK society that leads and influences the development of UK education and *** to the UK government figures in 2018,statistics show that“the employment rate of British White stood at 75%,with the overall employment rate in the UK stood at 74%”(UK Government,2018).At the GCSE level in 2018,it is demonstrated that“there are more than 63%of British White pupils who achieved A*to C levels in English and mathematics exams”(UK Government,2018),higher than the excellence rate of Mixed(30%),Black Caribbean(51%),and Pakistani(58%).It is obvious that British White people are highly prioritized in UK society,especially in educational fields due to the unequal distribution of educational resources between British Whites and other ethnic groups in UK ***,there are also some of the inequalities that exist among British Whites,as their differences gender,regions,and socio-economic *** paper aims to have an exploration on the British White education in a further step in terms of how the inequalities exist in their education,primarily from the lens of international education as assimilation,social reproduction,and gender issues.

关键词： British education educational assimilation social production genders

Structure tailorable triple-phase and pure double-polar-phase flexible IF-WS_(2)@poly(vinylidene fluoride)nanocomposites with enhanced electrical and mechanical properties

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Journal of materiomics 2020年第3期6卷 563-572页

作者： Dong Guo Kai Cai Pingye Deng Guoning Si Liangying Sun Fahui Chen Honglong Ning Li Jin jingtao ma School of Medical Instrument&Food Engineering University of Shanghai for Science&TechnologyShanghai200093China School of materials Science&Engineering Beihang UniversityBeijing100191China Beijing Center for Physical and Chemical Analysis Beijing100089China Institute of Polymer Optoelectronic materials and Devices State Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhou510640China Electronic materials Research Laboratory School of Electronic and Information EngineeringXi’an Jiaotong UniversityXi’an710049China State Key Laboratory of New Ceramics and Fine Processing Tsinghua UniversityBeijing100084China

A new low-cost high-permittivity flexible nanocomposite consisting of a polyvinylidene fluoride(PVDF)matrix and fullerene-like tungsten disulfide nanoparticle(IF-WS2 NP)filler was fabricated via a simple solution route.A comprehensive investigation by X-ray diffraction,attenuated total reflection-infrared spectroscopy,and differential scanning calorimetry(DSC)showed that 0.5e1 vol% of IF-WS_(2) induced a nonpolar α-phase to coexisting triple-phase transition in PVDF,whereas a slightly higher loading of 2 vol% induced pure double-polar β- and γ-*** results indicate that the structure and properties of the fabricated nanocomposite are easily *** during heating and cooling cycles and morphology observations further indicated that a polar phase was induced by the nucleation effect of the IF-WS2 NPs and electrostatic *** a consequence of the multiphase coexistence and structure homogeneity,nanocomposites with approximately 0.5-1 vol% of IF-WS_(2) NPs showed enhanced dielectric and energy-storage performance as well as enhanced tensile strength and *** new phase-tailorable nanocomposites with balanced properties are promising for applications as energystorage capacitors,piezoelectric sensors,and other flexible multifunctional *** results of this study will serve to deepen the understanding of the polymer polymorph and provide directions on new routes for fabrication of smart materials.

关键词： PVDF Polymorph Permittivity Piezoelectricity Flexibility

基于DPSIR模型的浙江省海域承载力的评价分析

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经济地理 2021年第11期41卷 48-55页

作者：黄晖胡求光马劲韬宁波大学商学院中国浙江宁波315211 宁波大学东海研究院中国浙江宁波315211

文章基于DPSIR框架模型,从驱动力、压力、状态、影响和响应5个方面构建包含10个要素层、33个代表性指标组成的海域承载力评价指标体系,运用熵值法对浙江海域承载力进行动态时序分析,利用耦合协调度模型衡量浙江海域承载力系统的综合协... 详细信息

文章基于DPSIR框架模型,从驱动力、压力、状态、影响和响应5个方面构建包含10个要素层、33个代表性指标组成的海域承载力评价指标体系,运用熵值法对浙江海域承载力进行动态时序分析,利用耦合协调度模型衡量浙江海域承载力系统的综合协调程度,并对海域承载力与经济发展要素进行拟合分析。研究发现:(1)除受2008年金融危机影响的年份外,2006—2016年浙江省海域承载力水平总体上扬趋势明显,响应和驱动力指标值对海域承载力影响明显。(2)浙江海域承载力系统耦合协调度偏低但呈现稳步上升的态势,系统耦合协调度偏低是制约海域承载力的障碍性因素。(3)经济发展与海域承载力呈显著正相关,表明产业结构优化、合理的经济布局是海域承载力提升的驱动力。最后提出相应的对策建议。

关键词：海域承载力生态环境可持续发展耦合协调度陆海统筹产业结构科技创新

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石化副产炭黑应用性能改进研究

石油炼制与化工 2006年第10期37卷 51-55页

作者：汤红梅马竞涛镇海炼化股份有限公司技术中心宁波315207

介绍了镇海炼化公司合成氨装置以脱油沥青为原料的副产炭黑的利用现状及应用性能,以及应用性能改进研究。试验结果表明:通过纯化工艺、超细粉碎、复配等过程处理,可以降低副产炭黑的灰分,提高拉伸强度及扯断伸长率,从而有效地改进副产... 详细信息

介绍了镇海炼化公司合成氨装置以脱油沥青为原料的副产炭黑的利用现状及应用性能,以及应用性能改进研究。试验结果表明:通过纯化工艺、超细粉碎、复配等过程处理,可以降低副产炭黑的灰分,提高拉伸强度及扯断伸长率,从而有效地改进副产炭黑的应用性能．为副产炭黑的有效利用提供可能。

关键词：沥青合成氨炭黑改性

契合与选择——传播视域下的马克思主义中国化

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理论导刊 2010年第2期 4-6页

作者：马惊涛李永枝国防大学12队北京100091 北京商务科技学校北京101101

从传播的视域阐释马克思主义中国化,进一步探寻其存在的可能与必然,直面意识形态面临的冲击与挑战,并作出客观的解读与展望,不仅仅是视角的变更和理论层次的完善,事实上也是在进一步探索马克思主义中国化更好的途径、方式,追寻马克思主... 详细信息

从传播的视域阐释马克思主义中国化,进一步探寻其存在的可能与必然,直面意识形态面临的冲击与挑战,并作出客观的解读与展望,不仅仅是视角的变更和理论层次的完善,事实上也是在进一步探索马克思主义中国化更好的途径、方式,追寻马克思主义在中国承继发展的内在规律。

关键词：马克思主义传播中国化

烧结温度对Al2O3-Y-Ce-TZP陶瓷低温时效的影响

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稀有金属材料与工程 2005年第Z1期34卷 316-318页

作者：林强张宝清林旭平马景陶新型陶瓷与精细工艺国家重点实验室清华大学核能与新能源技术研究院北京100084 新型陶瓷与精细工艺国家重点实验室清华大学核能与新能源技术研究院北京100084 新型陶瓷与精细工艺国家重点实验室清华大学核能与新能源技术研究院北京100084 新型陶瓷与精细工艺国家重点实验室清华大学核能与新能源技术研究院北京100084

研究了Al2O3-Y-Ce-TZP陶瓷材料的烧结特性,分析了不同烧结温度对Al2O3-Y-Ce-TZP陶瓷材料的烧结特性、相结构、显微结构的影响.通过对不同温度下烧结的Al2O3-Y-Ce-TZP陶瓷材料的时效实验研究,发现:在1 450℃下烧结的样品拥有较好的力学性... 详细信息

研究了Al2O3-Y-Ce-TZP陶瓷材料的烧结特性,分析了不同烧结温度对Al2O3-Y-Ce-TZP陶瓷材料的烧结特性、相结构、显微结构的影响.通过对不同温度下烧结的Al2O3-Y-Ce-TZP陶瓷材料的时效实验研究,发现:在1 450℃下烧结的样品拥有较好的力学性能,并能较好的抑制时效,烧结温度过高(高于1 500℃)将导致晶粒异常长大,促使氧化锆四方相向单斜相的马氏体相变加快,从而导致材料性能降低.

关键词：马氏体相变时效烧结温度氧化锆陶瓷