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3种煤焦的CO_2气化反应特性及动力学模型

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煤炭学报 2015年第9期40卷 2193-2199页

作者：董倩张海霞朱治平中国科学院工程热物理研究所北京100190 中国科学院大学北京100049

为探索不同煤种的气化反应特性及其动力学,以神木煤、新疆准东煤和印尼加里曼丹岛煤3种煤质差异较大的低阶煤为原料,在水平管式炉上制备了3种煤样的900℃快速热解煤焦,并采用热重分析仪考察了3种煤焦的非等温和等温气化特性,用分布活化... 详细信息

为探索不同煤种的气化反应特性及其动力学,以神木煤、新疆准东煤和印尼加里曼丹岛煤3种煤质差异较大的低阶煤为原料,在水平管式炉上制备了3种煤样的900℃快速热解煤焦,并采用热重分析仪考察了3种煤焦的非等温和等温气化特性,用分布活化能模型和随机孔模型拟合了煤焦的CO2气化反应速率与碳转化率间的关系。研究结果表明:煤焦的非等温气化反应活性和等温气化反应活性存在一定的差异,气化温度、煤种及煤灰分中的碱金属均影响气化反应活性,煤焦的等温气化反应活性为印尼加里曼丹岛煤焦的最高,神木煤焦最低,气化温度对神木煤焦的影响更显著。分布活化能模型和随机孔模型计算的活化能存在一定的关联;随机孔模型能较好地拟合煤焦气化实验数据。

关键词：煤焦热重分析气化活性动力学模型

Clinical Treatment and Anatomy Study of Maxillary First Molars with Five Root Canals

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Chinese Medical Sciences Journal 2011年第2期26卷 129-131页

作者： Kuo Wan Shun-yun Luo Ji-zhi Zhao hai-yun Wang Lin Ma Wen-dong Yang Department of Stomatology Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730 China

THE purpose of root canal treatment is to thoroughly clean the root canal system and fill it in all its dimensions.I To achieve this goal, the entire root canal system must be adequately debrided and completely filled. In clinical practice, variations in the canal morphology pose a constant challenge to endodontists in deciding on accurate diagnosis and appropriate management. Knowledge of these variations is crucial for a successful endodontic treatment, especially in absence of an operating microscope or cone-beam computered tomography （CBCT）.

关键词： endodontics maxillary first molar root canal system

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湍流模型对压气机数值模拟精度的影响

航空动力学报 2010年第12期25卷 2683-2689页

作者：尹松金东海朱芳桂幸民北京航空航天大学能源与动力工程学院北京100191

开发了一个求解叶轮机全三维黏性流场的程序,采用了目前叶轮机数值模拟中常用的且模拟性能较好的三种湍流模型:k-ε模型,k-ω模型,Spalart-All maras(S-A)模型,计算了跨声压气机NASA(National Aeronautics and Space Administration)Rot... 详细信息

开发了一个求解叶轮机全三维黏性流场的程序,采用了目前叶轮机数值模拟中常用的且模拟性能较好的三种湍流模型:k-ε模型,k-ω模型,Spalart-All maras(S-A)模型,计算了跨声压气机NASA(National Aeronautics and Space Administration)Rotor 37的流场,并与实验进行了性能参数、三维流场和角区流动的对比分析.考察在相同的数值计算平台上进行比较这几个湍流模型对压气机的数值模拟性能的影响.最终结果表明:对于具有强剪切、存在分离流的复杂的叶轮机三维流场来说,k-ω模型数值模拟精度更高,相比其他两个模型具有一定的优势.

关键词：压气机三维黏性流场数值模拟角区流动湍流模型

Roles of sphincter of Oddi motility and serum vasoactive intestinal peptide,gastrin and cholecystokinin octapeptide

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World Journal of Gastroenterology 2014年第16期20卷 4730-4736页

作者： Zhen-hai Zhang Cheng-Kun Qin Shuo-dong Wu Jian Xu Xian-Ping Cui Zhi-Yi Wang Guo-Zhe Xian Department of Hepatobiliary Surgery Shandong Provincial Hospital Affiliated to Shangdong University Departments of Minimally Invasive Surgery and the Second General Surgery Shengjing Hospital of China Medical University

AIM: To investigate roles of sphincter of Oddi (SO) motility played in pigment gallbladder stone formation in model of guinea pigs.

关键词： Pigment gallstone Sphincter of Oddi Manometry Myoelectric activity Guinea pig Vasoactive intestinal peptide Gastrin Cholecystokinin octapeptide

Super long-range diffusion of carbon during proeutectoid ferrite transformation

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Journal of Central South University 2019年第3期26卷 560-566页

作者： ZHANG Suo-quan JIAO Si-hai DING Jian-hua WAN Di LIU Zhen-yu WANG Guo-dong State Key Laboratory of Rolling and Automation Northeastern University Research Institute Baoshan Iron & Steel Co. Ltd. Department of Mechanical and Industrial Engineering Norwegian University of Science and Technology

In order to explore the possible diffusion distance of carbon during proeutectoid ferrite transformation, a slow cooling test of low carbon steel was carried out under vacuum of the thermal simulator. The microstructure and thermal expansion curve were discussed and the carbon concentration inside the sample was measured. The ferrite layer of about 450 μm thickness was obtained without pearlite on the surface of the sample in the microstructure. The thermal expansion curve shows that the ferrite layer without pearlite is formed during the local phase transformation, which is followed by the global transformation. The carbon concentration in the core of the sample (0.061%) is significantly higher than that of the bulk material (0.054%). All results show that carbon has long-range diffusion from the outer layer to the inner layer of the sample. The transformation is predominantly interface-controlled mode during local transformation, and the interface migration rate is about 2.25 μm/s.

关键词： low carbon steel local transformation super long-rang diffusion interface-controlled mode

Fine Particulate Matter Exposure Induces Toxicity by Regulating Nuclear Factor-κB/toll-like Receptor 4/myeloid Differentiation Primary Response Signaling Pathways in RAW264.7 Cells

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Biomedical and Environmental Sciences 2023年第5期36卷 458-462页

作者： ZHENG Mei zhu LU Yao LU Ting Ting QIN Peng LI Yu Qiu SHI dong Fang The Central Laboratory Changchun Normal UniversityChangchun 130000JilinChina College of Life Science Changchun Normal UniversityChangchun 130000JilinChina Soybean Research Institute Jilin Academy Agricultural of ScienceChangchun 130033JilinChina

Global air pollution has become a major threat to human health. Daily variations in air pollution have been linked to increased risks of cardiopulmonaryrelated morbidity and mortality. In particular, fine particulate matter(PM) with an aerodynamic diameter ≤ 2.5 μm(PM2.5), which mostly originates from coal combustion, vehicle exhaust, and open sources in Chinese cities, is detrimental to health[1].Epidemiological and experimental investigations have demonstrated that long-term exposure to PM2.5, the most dangerous particulate in the Earth’s atmosphere, is a pivotal risk factor for cardiorespiratory diseases.

关键词： pollution mostly Earth

Retention behaviour of carboxylic acid methyl esters in supercritical fluid chromatography

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Chinese Journal of Chemistry 1994年第2期12卷 129-137页

作者： SHEN, Yu-Feng WANG, Qing-hai zhu, Dao-Qian ZHOU, Liang-Mo Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116012, China Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian Liaoning 116012 China

The study on retention behavior in supercritical fluid chromatography (SFC) is necessary to understand the mechanism of the various interactions in SFC. The retention of SFC in carboxylic acid methyl ester/polymethylsiloxane/CO2 system was studied systematically and the retention behavior of this kind of compounds under various typical operation conditions was described using the method of an alternative unified theory of chromatographic retention. The results illustrated that expression: Ink.= a + b/T + cp + dp/T + ep2/T can be used to describe quantitatively the retention behavior of carboxylic acid methyl ester/polymethylsiloxane/CO2 system in the ranges of reduced density from 0.549 to 1.411. It was also found that the entropy of solute in stationary phase is dependent on the density of supercritical fluid (SF) under typical operating conditions of SFC.

关键词： Supercritical fluid chromatography (SFC) retention behaviour carboxylic acid methyl esters retention equation of SFC.

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工业应用的S波段小型化连续波速调管的设计

真空电子技术 2024年第2期 11-15页

作者：李闯卫博李冬凤冯海平王刚 FAN Ying-shan 北京真空电子技术研究所北京100015

速调管具有大功率、高效率、长寿命的特点和优势,在大科学和工业加热中有着广泛的应用。针对微波等离子体化学气相沉积(MPCVD)应用设计了一种10~15 kW级的小型化连续波速调管,速调管总重量小于30 kg,在电压16 kV、电子注电流2 A的状态... 详细信息

速调管具有大功率、高效率、长寿命的特点和优势,在大科学和工业加热中有着广泛的应用。针对微波等离子体化学气相沉积(MPCVD)应用设计了一种10~15 kW级的小型化连续波速调管,速调管总重量小于30 kg,在电压16 kV、电子注电流2 A的状态下获得了大于17 kW的输出功率,效率达到56%以上。

关键词：速调管连续波永磁聚焦注波互作用

Load transfer laws of tensile anchors in rock masses with weak interlayers based on a shear-slipping updating model

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Journal of Mountain Science 2022年第3期19卷 812-825页

作者： WANG Yan XIANG Xin LI Chang-dong zhu Guo-qiang SONG Cheng-bin XIAN Jin-ye ZHANG Jia-jun Faculty of Engineering China University of GeosciencesWuhan 430074China China Three Gorges Corporation Limited Beijing 100038China Three Gorges Research Center for Geo-hazards Ministry of Education China University of GeosciencesWuhan 430074China

The load transfer characteristics of a tensile anchor in the rock mass with weak interlayers were investigated,considering the nonuniform stress of the horizontally layered rock mass along *** improved shear-slipping model was proposed to describe the stress evolution characteristics of the bolt-rock *** on the improved model,analytical solutions of the axial force,shear stress distribution and load-displacement relationship considering the residual stress stage were *** effects of the stratigraphic sequence,pulling force and bolt diameter on the stress distribution of the anchorage interface were evaluated by using analytical *** results were verified by applying the finite difference numerical simulation *** sensitivity of each parameter to the axial force and shear stress of the rock bolt was determined based on calculation of the sensitivity *** study results show that the axial force and shear stress tend to decrease nonuniformly along the rock bolt towards the anchorage *** to the existence of weak interlayers,the shear stress mutates at the weak and hard rock interface,and the axial force appears to“rebound”at the bottom of the anchored *** has more significant effects on the axial force and shear stress at the bottom of the anchor than at the top of the *** pulling force is more sensitive to the anchor stress than stratigraphic sequence when the bolt diameter is *** study provides a theoretical framework for the fundamental problem of tensile bolts in horizontally or vertically laminated rock masses,providing a theoretical basis for anchor design.

关键词： Weak interlayer Tensile anchor Residual stress Shear-slipping updating model Sensitivity