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Mechanical behaviors and energy absorption properties of Y/Cr and Ce/Cr coated open-cell nickel-based alloy foams

Rare Metals 2018年第8期37卷 650-661页

作者： Zhi-Li Hu Qiu Pang guo-qiang ji Gao-Hui Wu State Key Laboratory of Advanced Welding and Joining HarbinInstitute of TechnologyHarbin 150001China Hubei Key Laboratory of Advanced Technology of Automobile Components Wuhan University of TechnologyWuhan 430070China School of Mechanical and Electrical Engineering Wuhan Donghu UniversityWuhan 430212China Materials Test Department China National Analytical CenterGuangzhou 510070China

In this study, Y-and Ce-modified Cr coatings applied by pack cementation method were prepared on the surface of open-cell nickel-based alloy foam. The morphologies and microstructures of Y- and Ce-modified Cr coatings with various Y and Ce contents were investigated in detail. Then, the effects of Y and Ce addition on the mechanical properties of open-cell nickel-based alloy foams were analyzed and compared. Simultaneously, the energy absorption capacity and energy absorption efficiency of the Y- and Ce-modified Cr coated alloy foams were discussed and compared at the room and high temperatures. The results show that Cr coatings containing minor amounts of rare earth element （Y and Ce） are well adhered to the nickel-based foam struts. Especially, the microstructure of the 2 wt% Ce-modified Cr coating is denser and uniform. In addition, the compressive strength and plateau stress of Y- and Ce-modified Cr coated alloy foams firstly increase and then decrease by increasing the Y and Ce contents at room and high temperatures. The energy absorption capacity of Y/Cr and Ce/Cr coated alloy foams increases linearly with the strains increasing. The Ce/Cr coated alloy foams can absorb more energy than Y/Cr coated alloy foams in the plateau and densification regions at room temperature. Compared to those at room temperature, the Y- and Ce-modified Cr coated alloy foams show higher energy absorption efficiency when deforma- tion within 10%-30% at high temperature.

关键词： Open-cell nickel-based alloy foam Y-modified Cr coating Ce-modified Cr coating Pack cementation Mechanical properties

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First report of theropod materials enriches the dinosaur assemblages in Guangxi and expands the dinosaur distribution to the southernmost China

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China Geology 2025年第1期8卷 233-234页

作者： Xu-ri Wang Shu-bin Ju Yan-nan ji Zhen guo qiang ji Key Laboratory of Stratigraphy and Paleontology of the Ministry of Natural Resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Hebei GEO University Shijiazhuang 050031China Dalian Natural History Museum Dalian 116023China Chinese Academy of Geological Sciences Beijing 100037China

*** Dinosaur fossils were first discovered from Guangxi Zhuang Autonomous Region in 1960s,mainly including fossil bones and teeth from the *** one dorsal vertebra and one ischium were reported from the Late Jurassic a... 详细信息

关键词： Island Cretaceous Jurassic

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教化投资:人力资本投资的新形式

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经济学家 2006年第4期 78-84页

作者：郭继强浙江大学劳动保障与公共政策研究中心公共管理学院浙江杭州310027

本文针对现有的人力资本理论将人力资本投资形式局限于教育、培训、医疗、保健和迁移,而对其他投资形式关注不足的现实,认为适应于现代经济生活相关的思想观念、价值取向和道德规范,需要相关投入才会形成,这些投入也是人力资本投资不可... 详细信息

本文针对现有的人力资本理论将人力资本投资形式局限于教育、培训、医疗、保健和迁移,而对其他投资形式关注不足的现实,认为适应于现代经济生活相关的思想观念、价值取向和道德规范,需要相关投入才会形成,这些投入也是人力资本投资不可或缺的形式,笔者将其概括为教化投资。经济转型过程凸显了教化投资的重要性。教化投资增强了人力资本的资源配置能力,在扩大个体人力资本存量的同时,还提升了社会经济价值,增加了社会资本。

关键词：教化人力资本投资资源配置能力

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马克思工资和失业理论的现代经济学理解

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教学与研究 2007年第5期 36-43页

作者：郭继强浙江大学公共管理学院浙江杭州310027

马克思的工资和失业理论指出,资本主义社会中工人的工资趋向于工资的最低限度(劳动力价值的最低限度),同时,工人的失业问题也如影随形。作为对经济运行的一种规律性描述,类似景象也显现于许多处在工业化初期的国家或者发展中国家,具有... 详细信息

马克思的工资和失业理论指出,资本主义社会中工人的工资趋向于工资的最低限度(劳动力价值的最低限度),同时,工人的失业问题也如影随形。作为对经济运行的一种规律性描述,类似景象也显现于许多处在工业化初期的国家或者发展中国家,具有相当的普遍性。本文通过构建一个基于向下倾斜劳动供给曲线的工资和就业决定模型,在现代经济学的表现形式下诠释了这种景象,进而将马克思的有关精辟见解在现代经济学语境下用于改进这种景象。

关键词：劳动供给拐点保留工资失业

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Distributed optimal consensus control for multiagent systems based on event-triggered and prioritized experience replay strategies

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Science China(Information Sciences) 2025年第1期68卷 306-321页

作者： Cuijuan ZHANG Lianghao ji Shasha YANG Xing guo Huaqing LI Chongqing Key Laboratory of Image Cognition Chongqing University of Posts and Telecommunications Key Laboratory of Intelligent Perception and Computing of Anhui Province Anqing Normal University College of Electronic and Information Engineering Southwest University

This study uses event-triggered(ET) and reinforcement learning methods to investigate the optimal consensus control problem for cooperative-competitive multiagent systems. It proposes a novel distributed ET control strategy, which relies on a prioritized experience replay(PER) policy. This strategy not only conserves communication resources but also ensures acceptable system performance. To implement the proposed method, actor-critic(AC) dual-structured neural networks(NNs) are used to approximate the value function and control policy. In the AC NNs, the weight estimates for the NNs are updated at the moment of event triggering, resulting in a nonperiodic weight adjustment pattern. This approach decreases the computational cost in comparison with the traditional ET mechanism. The PER-based ET mechanism makes full use of valid historical data and effectively establishes a balance between system performance and communication resource ***, it does not require the following two conditions in most existing studies:(1) requirement of the system dynamics model to be known, and(2) persistent excitation. In addition, Zeno behavior is excluded from this study. Finally, a simulation is conducted to confirm the validity of the suggested approach.

关键词： multiagent systems event-triggered mechanism prioritized experience replay dual-structured neural networks optimal consensus control

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我国大学高水平篮球队选材现状及对策研究

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中国体育科技 2000年第11期36卷 30-31页

作者：郭吉强徐州医学院体育教研室江苏徐州221002

通过文献资料、调查访问和逻辑分析等方法 ,对我国大学高水平篮球队选材现状进行调查与分析。结果显示 ,目前我国大学高水平篮球队的运动员主要来自体工队 (少体校 )和中学篮球二级以上的运动员 ,其中 ,中学生篮球运动员占多数 ,具体选... 详细信息

通过文献资料、调查访问和逻辑分析等方法 ,对我国大学高水平篮球队选材现状进行调查与分析。结果显示 ,目前我国大学高水平篮球队的运动员主要来自体工队 (少体校 )和中学篮球二级以上的运动员 ,其中 ,中学生篮球运动员占多数 ,具体选拔工作由主教练负责。

关键词：篮球选材现状对策大学

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Effects of the extrusion parameters on microstructure,texture and room temperature mechanical properties of extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 136-146页

作者： Chenjin Zhang Guangyu Yang Lei Xiao Zhiyong Kan jing guo qiang Li Wanqi jie State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108China College of Chemistry and Environmental Science Qujing Normal UniversityQujing 655011China

Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed *** dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)*** the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical-rare-earth(RE)*** alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening *** results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.

关键词： Mg-rare earth alloys extrusion temperature extrusion ratio extrusion speed strengthening mechanisms

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Metrological traceable calibration of organic carbon and elemental carbon based on laboratory-generated reference materials

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Journal of Environmental Sciences 2025年第3期149卷 524-534页

作者： Yue Liu Junjie Liu ji Xiao jing Ye Lixu guo Caiqing Yan Center for Environmental Metrology National Institute of Metrology ChinaBeijing 100029China College of Chemistry and Chemical Engineering Taiyuan University of TechnologyTaiyuan 030024China Environment Research Institute Shandong UniversityQingdao 266237China

Carbonaceous aerosol,including organic carbon(OC)and elemental carbon(EC),has significant influence on human health,air quality and climate *** measurement of carbonaceous aerosol is essential to reduce the uncertainty of radiative forcing estimation and source *** accurate separation of OC and EC is controversial due to the charring of ***,the development of reference materials(RM)for the validation of OC/EC separation is an important basis for further *** RMs were mainly based on ambient air sampling,which could not provide traceability of OC and EC *** develop traceable RMs with known OC/EC contents,our study applied an improved aerosol generation and mixing technique,providing uniform deposition of particles on quartz *** generate OC aerosol with similar pyrolytic property of ambient aerosol,both water soluble organic carbon(WSOC)and water insoluble organic carbon(WIOC)were used,and amorphous carbon was selected for EC *** RMs were analyzed using different *** homogeneity within the filter was validated,reaching below 2%.The long-term stability of RMs has been validated with RSD ranged from 1.7%–3.2%.Good correlationwas observed between nominal concentration of RMswithmeasured concentration by two protocols,while the difference of EC concentration was within 20%.The results indicated that the newly developed RMs were acceptable for the calibration of OC and EC,which could improve the accuracy of carbonaceous aerosol ***,the laboratory-generated EC-RMs could be suitable for the calibration of equivalent BC concentration by Aethalometers.

关键词： Carbonaceous aerosol Split point Reference material Laboratory-generated Traceability

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Characterization of petrophysical and seismic properties for CO2 storage with sensitivity analysis

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Petroleum Science 2025年第1期22卷 193-209页

作者： Yan-jiao Dong Yi Shen Kai guo Xiao-Qin Wu qiang Mao Wen-Yue Sun Zhi-qiang Wang State Key Laboratory of Offshore Oil and Gas Exploitation Geosciences Department China University of Petroleum (East China) CNOOC Research Institute Ltd. School of Petroleum Engineering China University of Petroleum (East China)

Saline aquifers are considered as highly favored reservoirs for CO2sequestration due to their favorable properties. Understanding the impact of saline aquifer properties on the migration and distribution of CO2plume is crucial. This study focuses on four key parameters—permeability, porosity, formation pressure, and temperature—to characterize the reservoir and analyse the petrophysical and elastic response of CO2. First, we performed reservoir simulations to simulate CO2saturation, using multiple sets of these four parameters to examine their significance on CO2saturation and the plume migration ***, the effect of these parameters on the elastic properties is tested using rock physics *** established a relationship of compressional wave velocity（Vp） and quality factor（Qp） with the four key parameters, and conducted a sensitivity analysis to test their sensitivity to Vpand Qp. Finally, we utilized visco-acoustic wave equation simulated time-lapse seismic data based on the computed Vpand Qpmodels, and analysed the impact of CO2saturation changes on seismic data. As for the above numerical simulations and analysis, we conducted sensitivity analysis using both homogeneous and heterogeneous models. Consistent results are found between homogeneous and heterogeneous models. The permeability is the most sensitive parameter to the CO2saturation, while porosity emerges as the primary factor affecting both Qpand Vp. Both Qpand Vpincrease with the porosity, which contradicts the observations in gas reservoirs. The seismic simulations highlight significant variations in the seismic response to different parameters. We provided analysis for these observations, which serves as a valuable reference for comprehensive CO2integrity analysis, time-lapse monitoring, injection planning and site selection.

关键词： CO2 storage Time-lapse seismic CO2 plume Sensitivity analysis Rock physics Reservoir simulation Saline aquifer

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催乳素对葡萄球菌肠毒素A诱导的人外周血T细胞凋亡的影响

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中华微生物学和免疫学杂志 2007年第12期27卷 1127-1131页

作者：郭继强宋向凤牛志国新乡医学院免疫学教研室 453003

目的探讨催乳素(PRL)在T细胞的活化诱导凋亡(activation induced cell death,AICD)中的作用。方法用葡萄球菌肠毒素(SEA)体外刺激人外周血T细胞作为T细胞AICD的模型,在第2次向模型中加入SEA诱导T细胞凋亡的同时,分别加入3种不同浓度的hP... 详细信息

目的探讨催乳素(PRL)在T细胞的活化诱导凋亡(activation induced cell death,AICD)中的作用。方法用葡萄球菌肠毒素(SEA)体外刺激人外周血T细胞作为T细胞AICD的模型,在第2次向模型中加入SEA诱导T细胞凋亡的同时,分别加入3种不同浓度的hPRL(20、300和1000 ng/ml)进行干预,同时设不含hPRL的对照组。0～24 h内,以MTT法检测T细胞的增殖情况。PI染色后用流式技术检测细胞凋亡情况,并通过琼脂糖凝胶电泳检测T细胞凋亡DNA。流式检测T细胞的Fas和FasL的表达水平变化。Western blot法检测T细胞内凋亡相关蛋白Bcl-2和Bax。结果在T细胞的AICD模型中高浓度PRL组(300、1000 ng/ml)其T细胞增殖得到显著维持(P<0.05),各PRL处理组T细胞凋亡率比对照组降低了32.9%～78.2%(P<0.05)。PRL组(300、1000 ng/ml)Bax/Bcl-2比值比对照组下降了44.4%～46.0%(P<0.05)。PRL可明显抑制细胞表面Fas和FasL的表达,其中各PRL处理组Fas的细胞阳性率比对照组下降了51.1%～75.0%(P<0.01),FasL的细胞阳性率比对照组下降了28.2%～39.1%(P<0.01)。结论在SEA诱导T细胞的AICD过程中,PRL可通过抑制Fas、FasL和Bax的表达,并提高Bcl-2的表达,来抑制T细胞凋亡,维持T细胞的增殖。

关键词：葡萄球菌肠毒素A 细胞凋亡催乳素增殖活化诱导凋亡

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