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Preparation and Oxidation Resistance of BN-MgAlON Composites by Hot-pressing Sintering

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Journal of Iron and Steel Research International 2015年第5期22卷 423-430页

作者： Ran LIU Xin-yuan ZHANG Xing-juan WANG ya-na qie Qing L Fu GAO Key Laboratory for Advanced Metallurgy Technology of Ministry of Education Hebei United University College of Metallurgy and Energy Hebei United University

BN-MgA1ON composites were prepared by hot-pressing sintering under nitrogen atmosphere with BN-Mg- A1ON composite powders as raw material and Y2 O3 as sintering additive. Based on thermodynamic analysis, the oxi- dation resistance of BN-MgAION composites was investigated and the dynamics of oxidation process was also ana- lyzed. The oxidation process and the micro-morphology of the samples before and after oxidation were characterized by X-ray diffraction and scanning electron microscopy. The dynamics of oxidation resistance of the BN-MgA1ON composites was investigated via the analysis of the constant temperature oxidation mass gain curves. The results show that the main components of the material are MgA1ON, Sialon, BN and CayaI3 07 at 1 650--1750 ＊C, and the content of Caya1307 decreases as the sintering temperature increases. The BN-MgA1ON composites prepared at 1750 ℃ is uniform and compact with the balanced distributions of A1, Mg, O, and N. The oxidation process of BN- MgA1ON composites in air mainly consists of MgAION, Sialon and BN oxidation. The section after being oxidized at 1000--1300 ℃ involves three layers, namely, the outer layer, the middle layer and the inner layer. The oxidation process follows the parabola model. The apparent activation energy of the oxidation process is 2.13 × 10 5 J/mol and the frequency factor is 4.66 × 10 6.

关键词： boron-rich slag carbothermal reduction nitridation hot-pressing sintering BN-MgAION compositeoxidation resistance

Stomatal dynamics are regulated by leaf hydraulic traits and guard cell anatomy in nine true mangrove species

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Plant Diversity 2024年第3期46卷 395-405页

作者： ya-Dong qie Qi-Wei Zhang Scott A.M.McAdam Kun-Fang Cao State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of ForestryGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Forest Ecology and Conservation College of ForestryGuangxi UniversityNanning 530004China Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection Ministry of EducationGuangxi Normal UniversityGuilin 541001China Guangxi Key Laboratory of Landscape Resources Conservation and Sustainable Utilization in Lijiang River Basin Guangxi Normal UniversityGuilin 541001China Purdue Center for Plant Biology Department of Botany and Plant PathologyPurdue UniversityWest LafayetteIN 47907USA

Stomatal regulation is critical for mangroves to survive in the hyper-saline intertidal zone where water stress is severe and water availability is highly ***,very little is known about the stomatal sensitivity to vapour pressure deficit(VPD)in mangroves,and its co-ordination with stomatal morphology and leaf hydraulic *** measured the stomatal response to a step increase in VPD in situ,stomatal anatomy,leaf hydraulic vulnerability and pressure-volume traits in nine true mangrove species of five families and collected the data of genome *** aimed to answer two questions:(1)Does stomatal morphology influence stomatal dynamics in response to a high VPD in mangroves?with a consideration of possible influence of genome size on stomatal morphology;and(2)do leaf hydraulic traits influence stomatal sensitivity to VPD in mangroves?We found that the stomata of mangrove plants were highly sensitive to a step rise in VPD and the stomatal responses were directly affected by stomatal anatomy and hydraulic ***,denser stomata was correlated with faster stomatal closure at high VPD across the species of Rhizophoraceae,and stomata size negatively and vein density positively correlated with genome *** negative leaf osmotic pressure at the full turgor(πo)was related to higher operating steady-state stomatal conductance(gs);and a higher leaf capacitance(Cleaf)and more embolism resistant leaf xylem were associated with slower stomatal responses to an increase in *** addition,stomatal responsiveness to VPD was indirectly affected by leaf morphological traits,which were affected by site salinity and consequently leaf water *** results demonstrate that mangroves display a unique relationship between genome size,stomatal size and vein packing,and that stomatal responsiveness to VPD is regulated by leaf hydraulic traits and stomatal *** work provides a quantitative framework to better understand of stomatal regulation in mangroves

关键词： Stomatal temporal kinetics Vapour-pressure deficit(VPD) Leaf water relations Leaf hydraulic vulnerability Leaf osmotic potential Genome size

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杨歗谷:泰戈尔相册里的成都学者

文史杂志 2025年第1期235卷 81-82页

作者：且志宇巴蜀书社

100年前,泰戈尔访华期间,与辜鸿铭一同拜会泰戈尔、并与泰戈尔合影的,有成都学者杨歗谷先生。新中国成立后其为四川省文史研究馆馆员。他喜考古研究,收藏品甚多,后无偿捐献给国家。他时常携带实物到课堂,与讲义相佐证,被称为“实物教授... 详细信息

100年前,泰戈尔访华期间,与辜鸿铭一同拜会泰戈尔、并与泰戈尔合影的,有成都学者杨歗谷先生。新中国成立后其为四川省文史研究馆馆员。他喜考古研究,收藏品甚多,后无偿捐献给国家。他时常携带实物到课堂,与讲义相佐证,被称为“实物教授”。他著作丰富,惜多遗失不存。

关键词：清华园合影写经用纸

A Review of Atmospheric Electricity Research in China from 2011 to 2018

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Advances in Atmospheric Sciences 2019年第9期36卷 994-1014页

作者： Xiushu qie Yijun ZHANG Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Department of Atmospheric and Oceanic Sciences and Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China Collaborative Innovation Centre on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China College of Earth and Planetary Science University of Chinese Academy of SciencesBeijing 100049China

Atmospheric electricity research has been conducted actively in China,having profited from the development and application of high temporal and spatial resolution lightning detection and location *** paper reviews the scientific advances made in the field of atmospheric electricity in China from 2011 to 2018,covering the following five aspects:(1)lightning detection and location techniques;(2)discharge processes and parameters associated with rocket-triggered lightning;(3)physical processes in natural lightning and attachment to the ground;(4)lightning activities and charge structure in different thunderstorms;and(5)effects of thunderstorms on the upper *** addition,some outstanding questions for future research are outlined.

关键词： atmospheric electricity lightning thunderstorm lightning location techniques

FORWARD KINEMATICS AnaLYSIS FOR A NOVEL 5-DOF PARALLEL MECHANISM USING TETRAHEDRON CONFIGURATIONS

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Chinese Journal of Mechanical Engineering 2007年第6期20卷 1-4页

作者： QI Ming qie yanhui School of Mechanical Engineering Tianjin University Tianjin 300072 China School of Mechanical Engineering Hebei University of Technology Tianjin 300130 China

Forward kinematics analysis of a novel 5-DOF parallel mechanism using tetrahedron configurations is presented. Such mechanism is suitable to many tasks requiring less than 6 DOFs. It consists of a movable platform connected to the base by five identical 6-DOF active limbs plus one active limb with its DOF being exactly the same as the specified DOF of the movable platform, which leads to its legs＇ topology 4-UPS/UPU. Based on the tetmhedron geometry, both closed-form solution with an extra sensor and numerical method using iterative algorithm are employed to obtain the forward kinematics solutions of the mechanism. Compared with the conventional methods, the proposed closed-form solution has the advantages in automatically avoiding unnecessary complex roots and getting a unique solution for the forward kinematics. Finally, an example shows that the proposed numerical algorithm is so effective that it enables a real-time forward kinematics solution to be achieved and the initial value can be chosen easily.

关键词： Forward kinematics Numerical analysis Parallel mechanism

东北黑土区农村闲置宅基地空间分异及驱动因素——以吉林省梅河口市为例

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国土与自然资源研究 2025年第1期 34-38页

作者：李佳楠郄瑞卿吉林农业大学经济管理学院吉林长春130000

在乡村振兴和国家粮食安全的大背景下,明晰黑土区农村闲置宅基地空间分异特征及驱动因素,有利于黑土区闲置宅基地的高效利用。本文从自然条件、区位条件、经济条件三个方面选取9个指标构建影响宅基地闲置率的指标体系,以梅河口市303个... 详细信息

在乡村振兴和国家粮食安全的大背景下,明晰黑土区农村闲置宅基地空间分异特征及驱动因素,有利于黑土区闲置宅基地的高效利用。本文从自然条件、区位条件、经济条件三个方面选取9个指标构建影响宅基地闲置率的指标体系,以梅河口市303个行政村宅基地为研究对象,利用地理探测器、空间自相关和逐步回归分析等方法,从村级小尺度微观研究黑土区农村闲置宅基地空间分异及驱动因素。结果表明,(1)农村闲置宅基地分布存在明显区域差异性和空间集聚性。(2)各指标因子在作用方向和作用强度上对农村宅基地闲置率影响各不相同。(3)研究区农村闲置宅基地的7大主导驱动因素是平均坡度、平均高程、到镇政府距离、到县城距离、到干道距离、到河流距离、人均耕地面积。(4)闲置宅基地的形成是各影响因子综合作用的结果。

关键词：闲置宅基地空心化空间分异驱动因素黑土区

Analysis and Modeling of Calendar Aging and Cycle Aging of LiCoO_(2)/Graphite Cells

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Journal of Thermal Science 2024年第3期33卷 1109-1118页

作者： WANG Wei YUAN Baoqiang SUN qie WENNERSTEN Ronald Institute of Thermal Science and Technology Shandong UniversityJi’nan250061China School of Energy and Power Engineering Shandong UniversityJi’nan250061China Institute for Advanced Science and Technology Shandong UniversityJi’nan250061China

Lithium-ion batteries are used in a wide range of ***,their cycle life suffers from the problem of capacity fade,which includes calendar and cycle *** effects of storage time,temperature and partial charge-discharge cycling on the capacity fade of Li-ion batteries are investigated in this *** calendar aging and cycle aging are presented based on the storage and cycling experiment on LiCoO_(2)/graphite cells under different storage temperature and different ranges of state of charge(SOC).Based on the measurement data,a one-component and a double-component aging model are presented to respectively describe the capacity fade caused by calendar and cycle *** calendar aging of LiCoO_(2)/graphite batteries is mainly affected by temperature and SOC during the *** SOC and change in SOC(ΔSOC)are the main factors affecting battery degradation during cycling operation.

关键词： Lithium-ion battery LiCoO_(2)(LCO)/graphite calendar aging cycle aging lifetime model

Critical role of Toll-like receptor signaling in NK cell activation

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Chinese Science Bulletin 2012年第24期57卷 3192-3202页

作者： GUO qie ZHANG Cai Institute of lmmunopharmacology&lmmunotherapy School of Pharmaceutical SciencesShandong UniversityJinan 250012China

Toll-like receptors (TLRs) and NK cell receptors are the most important receptor superfamilies in innate immunity. TLRs act as the sensor of external pathogens, while NK cells detect alterations in endogenous protein expression on target cells through activating and inhibitory receptors. Accumulating data has demonstrated that TLRs and NK cell receptors can coordinate and regulate each other during immune responses, which contributes to the initiation of innate response and the priming of adaptive responses. TLRs can activate NK cell function directly or with the help of accessory cells in a cytokine or cell-to-cell contact dependent manner. More understanding of the recognition of innate receptors and interactions between them may provide important insights into the design of effective strategies to combat tumor and microbial infections. In this review, we summarize how TLRs and NK cells discriminate the self or non-self components respectively. And importantly, we pay more attention to the role of TLR sig-naling in induction of NK cell activation, responses and the crosstalk between them.

关键词： Toll样受体 NK细胞信号通路活化免疫反应细胞受体适应性反应微生物感染

Lightning Activity and Its Relation to the Intensity of Typhoons over the Northwest Pacific Ocean

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Advances in Atmospheric Sciences 2014年第3期31卷 581-592页

作者： PAN Lunxiang qie Xiushu WANG Dongfang Key Laboratory of the Middle Atmosphere and Global Environment Observation Institute of Atmospheric Physics Chinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology

ABSTRACT Data from the World Wide Lightning Location Network （WWLLN） were used to analyze the lightning activity and the relationship between maximum sustained wind and lightning rate in 69 tropical cyclones over the Northwest Pacific Ocean from 2005 to 2009. The minimum lightning density was observed in the category 2 typhoon Kong-Rey （2007）, with a value of only 1.15 d-1 （100 kin）-2. The maximum lightning density occurred in the category 2 typhoon Mitag （2007）, with a value of 510.42 d-1 （100 km）-2. The average lightning density decreased with radius from the typhoon center in both weak （categories 1-3） and super （categories 4-5） typhoons. The average lightning density in the inner core of super typhoons was more than twice as large as that for weak typhoons. Both groups of typhoons showed a near-monotonic decrease in lightning density with radius. Results also showed that lightning activity was more active in typhoons that made landfall than in those that did not. The mean correlation coefficient between the accumulated flashes within a 600-kin radius and the maximum wind speed in the weak typhoons and super typhoons was 0.81 and 0.74, respectively. For more than 78% （56%） of the super （weak） typhoons, the lightning activity peaked before the maximum sustained wind speed, with the most common leading time being 30 （60） h. The results suggest that, for the Northwest Pacific Ocean, lightning activity might be used as a measurement of the intensification of typhoons.

关键词： lightning typhoon intensity WWLLN