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EFFECTS OF GAS TYPE AND TEMPERATURE ON FINE PARTICLE FLUIDIZATION

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China Particuology 2006年第3期4卷 114-121页

作者： Chunbao xu J.-x. zhu Department of Chemical Engineering Lakehead University Thunder Bay Ontario P7B 5E1 Canada powder Technology Research Centre Department of Chemical & Biochemical Engineering The University of Western Ontario London Ontario N6A 5B9 Canada

The influence of gas type （helium and argon） and bed temperature （77-473 K） on the fluidization behaviour of Geldart groups C and A particles was investigated. For both types of particles tested, i.e., Al2O3 （4.8μm） and glass beads （39 μm）, the fluidization quality in different gases shows the following priority sequence： Ar 〉 He. In the same gaseous atmosphere, the particles when fluidized at an elevated temperature usually show larger bed voidages, higher bed pressure drops, and a lower Umf for the group A powder, all indicating an enhancement in fluidization quality. Possible mechanisms governing the operations of gas type and temperature in influencing the fluidization behaviours of fine particles have been discussed with respect to the changes in both gas properties and interparticle forces （on the basis of the London-van der Waals theory）. Gas viscosity （varying significantly with gas-type and temperature） proves to be the key parameter that influences the bed pressure drops and Umf in fluidization of fine particles, while the interparticle forces （also varying with gas-type and temperature） may play an important role in fine-particle fluidization by affecting the expansion behaviour of the particle-bed.

关键词： fluidization fine particles gas type temperature interparticle forces

PROCOAGULANT EFFECTS OF THROMBOLYTICTHERAPY IN ACUTE MYOCARDIAL INFARCTION

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Chinese Medical Sciences Journal 2002年第1期17卷 36-39页

作者： Wang Y Liu Q zhu J Yuan Z Ma x Department of Cardiology the First Hospital Xi''an Jiaotong University Xi''an 710061

To examine the procoagulant effects of thrombolytic agent on h emostasis and study the role of hemostatic markers as predictors of clinical outcomes. Methods. In the present study, eighteen patients with acute myocardial in farction(AMI) received 1.5 or 2.0 million U nonspecific urokinase(UK), or 70～80 mg fibrin specific recombinant tissue plasminogen activator(rt PA)and did not use heparin until 8 hours after intravenous injection of the above agents. Eig ht patients with AMI and without thrombolytic therapy were enrolled as controls. Coagulant and thrombolytic activity markers included thrombin antithrombin Ⅲ complex (TAT), D dimer, fibrinogen (Fg), FMPV/Amax. All markers were determined before,immediately,1,2,4 and 8 hours after the administration of thrombolytic a gents respectively. Results. Molecular marker of thrombin generation——TAT showed an activated coa gulant state immediately after thrombolytic therapy. Level of TAT showed no sign ificant changes between every two observed phases in controls. However, level of TAT increased significantly from 4.95±1.75μg/L ( 4.63±1.37μg/L) to 14.71±3 .31μg/L ( 14.25±2.53μg/L) before and immediately after administration of thro mbolytic agents UK(or rt PA). There was significant difference between level of serum TAT of patients with and without thrombolytic therapy (Px level than controls. D dimer, a surrogate of thrombolytic activity increased markedly and Fg significantly declined afte r thrombolytic therapy(Pxcess fibri nolysis induced by thrombolytic therapy. Both urokinase and rt PA had procoagul ant action. This transient activation of the coagulant system might contribute t o early reocclusion. These data provided the theoretical support for simultaneou s administration of antico

关键词： acute myocardial infarction thrombolysis urokinase rt PA

Influence of Re on the Properties of a NiCoCrAlY Coating Alloy

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Journal of Materials Science & Technology 2011年第5期27卷 408-414页

作者： J.J. Liang H. We Y.L. zhu x.F. Sun Z.Q. Hu M.S. Dargusch x.D. Yao Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Graduate School of Chinese Academy of Sciences Beijing 100039 China School of Materials & Mining Engineering The University of Queensland QLD 4072 Australia

MCrAIY can serve as stand-alone overlay coatings or bond coats in thermal barrier coating systems, and its properties play a vital role in determining the performance of these coating systems. In order to further understand the behavior of MCrAIY coatings, several NiCoCrAIY model alloys with different levels of Re （0.3 wt%, O wt%, and 9 wt%） were investigated. Microstructural observation showed the addition of Re promoted the precipitation of Cr-rich phases, such as α-Cr and σ. The presence of α-Cr lowered the coefficient of thermal expansion （CTE） of the coating alloys, which could reduce the CTE mismatch at the scale-metal interface. The solid solution strengthening effect of Re is responsible for an increase in Rockwell hardness of the coating alloys. But the isothermal oxidation resistance at 1100℃ was deteriorated due to the precipitation of brittle α-Cr phase, a phase of inferior oxidation resistance compared with β-NiAI and γ-Ni.

关键词： NiCoCrAIY Phase constitution Oxidation Thermal expansion behavior Hardness

DEGRADATION BEHAVIORS OF NEW TYPE TiV-BASED HYDROGEN STORAGE ELECTRODE ALLOYS

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Acta Metallurgica Sinica(English Letters) 2006年第1期19卷 68-74页

作者： x.Z. Sun Y. F. zhu Y. Lin R. Li M.x. Gao H. G. Pan Department of Materials Science and Engineering Zhejiang University Hangzhou310027 China

The degradation behaviors of the TiV-based multiphase hydrogen storage alloy Ti0.8Zr0.2V3.2Mn0.64 Cr0.96Ni1.2 during electrochemical cycling in alkaline electrolyte have been studied by xRD, SEM, EIS and AES measurements. xRD analysis indicates that the alloy consists of a C14-type Laves phase and a V-based solid solution. The lattice parameters of both phases are increased after discharged with cycling, which indicates that more irreversible hydrogen remains not discharged in the alloy. It shold be responsible for the decrease of discharge capacity. SEM micrographs show that after 10 electrochemical cycles, a large number of cracks can be observed in the alloy, existing mainly in the V-based solid solution phase. Moreover, after 30 cycles, the alloy particles are obviously pulverized due to the larger expansion and shrinkage of cell volumes during hydrogen absorption and desorption, which induces the fast degradation of the TiV-based hydrogen storage alloys. EIS and AES measurements indicate that some passive oxide film has been formed on the surface of alloy electrode, which has higher charge-transfer resistance, lower hydrogen diffusivity, and less electro-catalytic activity. Therefore it can be concluded that the pulverization and oxidation of the alloy are the main factors responsible for the fast degradation of the TiV-hased hydrogen storage alloys.

关键词： metal hydrides hydrogen storage alloy pulverization degradation

RELATIONSHIP AMONG EVAPORATION FLUx OF GROUNDWATER, DEPTH OF WATER TABLE AND NEGATIVE PRESSURE HEAD IN BARE SOIL

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Journal of Hydrodynamics 2000年第4期12卷 52-58页

作者： Qian, J.Z. zhu, x.Y. Zhou, N.Q. Li, G.Y. Dep. of Earth Sci. Nanjing Univ. Nanjing 210093 China

Evaporation of ground water is a part of moisture circulation in the field. And it is a main natural form in which water transmits from the ground water to the soil water and atmosphere water. According to the simulated experiments, we study the relationship among the evaporation, depth of groundwater table and negative pressure. By theoretical analysis of the experimental results, the main conclusions are drawn as follows. There are two abrupt points in every Q-H curve. The locations of the abrupt points are separately in step with the height of top of the capillary fringe and the height of maximal capillary rise in the soil section. When the depth of water table H is small, the evaporation flux of ground water is large. While the depth of water table exceeds the maximal capillary rise of media in vadose zone, the capillary rise breaks up and evaporation flux of groundwater is small. The water content ratio in ground surface tends to be zero and the surface of soil tends to be drought. These conclusions show that the maximal capillary rise of media in vadose zone is an important value in regulating rational depth of ground water to reduce the evaporation of ground water and to increase effective quantity of water resources. In the meantime, these conclusions are of important theoretical and practical significance to reduce the evaporation of ground water, to prevent and cure the salinization of soil, and to make full use of and protect water resources in the northern plains in China.

关键词： Capillarity Evaporation Soils

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基于视频游戏的空间能力测评

心理科学进展 2025年第1期33卷 11-24页

作者：尚俊杰石祝沈科杰北京大学教育学院学习科学实验室北京100871

空间能力是个体对客体或空间图形在头脑中进行识别、编码、贮存、表征、分解组合和抽象概括的能力,是个体理解自身所处环境并解决问题的认知基础。准确、便捷、有效地测评空间能力,对增强STEM教育教学水平和人才培养质量都具有重要意义... 详细信息

空间能力是个体对客体或空间图形在头脑中进行识别、编码、贮存、表征、分解组合和抽象概括的能力,是个体理解自身所处环境并解决问题的认知基础。准确、便捷、有效地测评空间能力,对增强STEM教育教学水平和人才培养质量都具有重要意义。由于空间能力受多因素共同作用,具有复杂性、多维度、内隐性的特点,使得利用计算机评价空间能力比较困难。本研究旨在准确、有效、大规模地测评空间能力,将使用多模态学习分析方法探索学习者空间认知行为表现特征,并基于视频游戏环境研发空间能力隐形测评关键技术与工具。具体包括:1)构建空间能力内在表征框架和评价指标体系;2)基于多模态学习分析构建学习者空间能力行为表现模型;3)探索视频游戏影响空间能力的关键因素,并使用游戏引擎开发基于视频游戏的测评工具;4)使用以证据为中心的设计框架和贝叶斯网络模型,开发并部署能够推断和预测空间能力的测评算法;5)在实验室和真实课堂情境开展实证研究,验证测评工具有效性。研究成果将有利于理解人类空间认知过程和行为表现,拓展和丰富空间能力相关理论,并为大规模数字化测评提供关键技术支撑。

关键词：基于游戏的测评空间能力多模态学习分析游戏化学习隐形测评

Reactive destabilization and bidirectional catalyzation for reversible hydrogen storage of LiBH_(4) by novel waxberry-like nano-additive assembled from ultrafine Fe_(3)O_(4) particles

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Journal of Materials Science & Technology 2024年第6期173卷 63-71页

作者： S.Wang M.H.Wu Y.Y.zhu Z.L.Li Y.x.Yang Y.Z.Li H.F.Liu M.x.Gao Department of Material Science Shenzhen MSU-BIT UniversityShenzhen 518172China State Key Laboratory of Silicon and Advanced Semiconductor Materials&School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China Institute of Resources Utilization and Rare Earth Development State Key Laboratory of Rare Metals Separation and Comprehensive UtilizationGuangdong Provincial Key Laboratory of Rare Earth Development and ApplicationGuangdong Academy of SciencesGuangzhou 510650China Institute of Science and Technology for New Energy Xi’an Technological UniversityXi’an 710021China National Supercomputing Center in Shenzhen Shenzhen 518055China

LiBH_(4) containing 18.5 wt.%H_(2) is an attractive high-capacity hydrogen storage material,however,it suffers from high operation temperature and poor ***,a novel and low-cost bifunctional additive,waxberry-like Fe_(3)O_(4) secondary nanospheres assembled from ultrafine primary Fe_(3)O_(4) nanoparticles,is synthesized,which exhibits significant destabilization and bidirectional catalyzation towards(de)hydrogenation of LiBH_(4).With an optimized addition of 30 wt.% waxberry-like Fe_(3)O_(4),the system initiated dehydrogenation below 100℃ and released a total of 8.1 wt.%H_(2) to 400℃.After 10 cycles,a capacity retention of 70% was achieved,greatly superior to previously reported oxides-modified *** destabilizing and catalyzing mechanisms of waxberry-like Fe_(3)O_(4) on LiBH_(4) were systematically analyzed by phase and microstructural evolutions during dehydrogenation and hydrogenation cycling as well as density functional theory(DFT)*** present work provides new insights in developing advanced nano-additives with unique structural and multifunctional designs towards LiBH4 hydrogen storage.

关键词： LiBH_(4) Hydrogen storage Waxberry-like Fe_(3)O_(4) Destabilization Catalysis

Effect of Active Mineral Filler on Rutting Performance and Fatigue Properties of Granite Asphalt Concrete

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武汉理工大学学报 2010年第17期32卷 55-58,82页

作者： zhu Z H WU S P LI W T HUANG x Key Laboratory of Silicate Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China Hubei Provincial Building Science Research & Design Institute Wuhan 430070China

Granite is well known as an acid aggregate. An active mineral filler produced in the laboratory is first used as an anti-stripping filler in the granite asphalt concrete. Four aggregate gradations were chosen in this study,and the effects of the active mineral filler and aggregates on the rutting resistance performance and fatigue properties of granite asphalt concrete were investigated by means of rutting test and four-point bending fatigue test. The results indicate that the dynamic stability of granite asphalt concrete increase significantly with the addition of active mineral filler and the fatigue properties can also be improved especially at lower strain level. Meanwhile,the results demonstrate that granite asphalt concrete has better rutting resistance performance and fatigue properties than limestone asphalt concrete.

关键词： granite asphalt concrete active mineral filler rutting resistance performance fatigue properties

Primary parenchymal squamous cell carcinoma of the kidney:A case report

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World Journal of Clinical Cases 2025年第4期13卷 34-40页

作者： Zhi-Hui Zheng Bo Shao Chao-Min xu Ke Wang Jia-zhu Wen Li-Kang Luo Jia-Cheng Guan Department of Ultrasound The Second People’s Hospital of QuzhouQuzhou 324000Zhejiang ProvinceChina Department of Radiology Shulan(Quzhou)HospitalQuzhou 324000Zhejiang ProvinceChina Department of Radiology The Second People’s Hospital of QuzhouQuzhou 324000Zhejiang ProvinceChina Department of Pathology The Second people’s Hospital of QuzhouQuzhou 324000Zhejiang ProvinceChina

BACKGROUND Primary squamous cell carcinoma(SCC)of the renal parenchyma is extremely rare,with only nine cases *** SUMMARY This study reports a 51-year-old man with primary SCC of the renal *** patient was admitted with recurrent dull pain and discomfort in the right lumbar region,which had worsened over 2 weeks,accompanied by painful gross *** antigen(SCCA)levels were elevated,and imaging revealed a renal mass with associated *** patient underwent laparoscopic unilateral nephrectomy and lymph node *** pathology confirmed highly differentiated SCC with necrosis in the right renal parenchyma,with negative renal pelvis and *** pathological stage was *** months after surgery,the tumor recurred with involvement of the liver,right psoas major muscle,and inferior vena *** patient refused chemotherapy and succumbed to the disease 6 months postoperatively due to disease *** We report a case of primary SCC of the renal parenchyma,a rare renal *** clinical symptoms,laboratory tests,and imaging findings are nonspecific,making accurate and timely diagnosis *** to the literature,for patients with renal calculi accompanied by a renal mass,elevated serum SCCA levels,and magnetic resonance imaging showing cystic or cystic-solid masses within the kidney with pseudocapsules and heterogeneous mild enhancement,the possibility of this disease should be considered.

关键词： Renal tumor Renal parenchyma Squamous cell carcinoma Renal calculi Computed tomography Case report