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Progress in twin roll casting of magnesium alloys: A review

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Journal of Magnesium and Alloys 2021年第2期9卷 362-391页

作者： Amjad Javaid frank Czerwinski CanmetMAtERIALS Natural Resources CanadaHamiltonOntarioL8P 0A5Canada

twin roll casting was commercialized for a strip production from ferrous and non-ferrous alloys in the 1950 s;however,its application to magnesium has proven difficult and still creates major *** report describes global efforts in expanding manufacturing capabilities of magnesium sheet through twin roll casting path,offering many benefits,including a reduction in number of processing steps and energy *** addition to hardware design,alloy transformation during processing,product microstructure and properties,examples of successful solutions along with present technology and knowledge limitations are discussed.A particular attention is paid to developments at Canmet MAtERIALS,having the only in North America pilot scale twin roll casting facility,devoted to *** are described that aim at design of new magnesium alloys,which could take advantage of unique processing conditions during twin roll casting and contribute to the overall progress in magnesium sheet manufacturing.

关键词： twin roll casting Magnesium alloys Solidification Magnesium sheet

Understanding earth / frank Press, Raymond Siever. 3RD EDITION

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Numerical and experimental investigation of sloshing under large amplitude roll excitation

2001年

作者： frank Press Raymond Siever.

来源：畅想之星图书光盘版（南... 评论

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Journal of Hydrodynamics 2021年第4期33卷 787-803页

作者： Ronja Hoch frank-Hendrik Wurm Institute of turbomachinery University of RostockRostockGermany

to enable a virtual design and optimization process of partially filled coolant tanks a reliable numerical approach is needed to predict the liquid and gas two phase flow inside the *** this study numerical results are validated by experimental data to examine the suitability of the method for the tank design *** liquid motion inside the tanks can be described as sloshing with high amplitude,off-resonant roll excitation and was examined using a homogeneous multiphase model and VOF interface capturing approach as well as an experimental setup including piezoelectric pressure sensors and qualitative observation of the free *** effect of two vertical baffles on the maximum pressure and the position of phase interface was *** comparison between the computational and experimental results reveals that the numerical model tends to under predict the experimental peak pressures but resolves the liquid surface in close agreement with the experiments.

关键词： Multiphase flows sloshing unsteady Reynolds averaged Navier-Stokes(URANS)

Articulated dental cast analysis of asymptomatic and symptomatic populations

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International Journal of Oral Science 2016年第2期8卷 126-132页

作者： frank E Cordray Department of Orthodontics College of Dentistry Ohio State University Columbus USA

Dental instrumentation has long provided insight into the mechanism of musculo-skeletal function of the gnathic system. While large population studies associate dental arch displacement （DAD）, especially laterally, with symptoms, mandibular condyle displacement （CD） resulting from DAD has not been targeted as possibly etiologic in the production of common muscle contraction headache （CMCH） and temporo-mandibular dysfunction （tMD）. the objective was to evaluate the three-dimensional nature of DAD and CD between the seated condylar position （SCP） and the intercuspal position （ICP） and to compare results derived from large deprogrammed asymptomatic and symptomatic populations. A total of 1 192 sets of dental casts collected from asymptomatic and symptomatic populations were articulated in the SCP. the initial occlusal contact, DAD, and condylar displacement were evaluated for frequency, direction, and magnitude of displacement between the SCP and ICP. the data revealed significant displacement between the SCP and ICP of the condyles （displaced most frequently inferior （down） and posterior （distal）） and substantially increased frequency and magnitude of displacement of the dental arches （with posterior premature occlusal contacts, increased overjet, decreased overbite, midline differences, and occlusal classification changes） in symptomatic subjects. these discrepancies were statistically significant and clinically significant. the data support the concept of increased DAD and CD with dysfunction. transverse condylar displacement, commonly presenting with dental cross bite, may be associated with CMCH and tMD. Displacement of the mandibular condyle may be an etiologic factor in CMCH and dysfunction of the temporo-mandibular joint.

关键词： dental arch displacement condylar displacement seated condylar position intercuspal position musculo-skeletaldysfunction temporo-mandibular dysfunction common muscle contraction headache

Comparing the Upper triassic Deep-sea Flysch of the Shannan terrane with the Coeval Shallow Shelf Sediments of the tethys Himalaya,Southern tibet

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Acta Geologica Sinica(English Edition) 2021年第2期95卷 348-354页

作者： LI Xianghui frank MAttERN School of Earth Sciences and Engineering Nanjing UniversityNanjing 210023China College of Science Earth Science DepartmentSultan Qaboos UniversityAl-KhodPO Box 36Sultanate of Oman

the provenance and paleogeography of the Upper triassic deep-sea flysch Langjiexue Group(LG)of the Shannan terrane in the northeastern Himalaya orogen,south of Yarlung Zangbo,have been disputed in recent years since its affinity to the tethys Himalaya was suspected during the early 2000 *** on the earlier discoveries of the Upper Permian–triassic basalts and mafic dykes from the LG and of coeval detrital zircons from the Qulonggongba Formation(QF)in shallow shelf sediments of the tethys Himalaya,the previous viewpoints on the basin and tectonics of the LG have been recently *** compared the two units of the Upper triassic,and our results reveal a number of differences,discrepancies,and inconsistencies in the debate,raising crucial questions on the postulation and provenance model of the remote Gondwanide Orogen for the *** is suggested that more observations and evidence are needed to further improve the paleogeographic understanding and relationship of the two units.

关键词： sedimentology paleogeography flysch shelf sediment Late triassic Shannan terrane tethys tibet

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差异化城市社区养老服务的适应性供给

贵州师范大学学报（社会科学版） 2024年第1期 97-106页

作者：龙斧李玉霞武汉大学社会学院湖北武汉430072 武汉大学战略决策研究中心湖北武汉430072 昆山杜克大学江苏昆山235100

当前,我国城市人口老龄化、高龄化现象严重,城市养老服务的供给压力随之越来越大。基于适应性供给研究视角发现,在城市化水平、社区治理能力、社区区位等因素共同作用下,社区资源禀赋及其形塑的社区支持体系差异化程度不断扩大,这就要... 详细信息

当前,我国城市人口老龄化、高龄化现象严重,城市养老服务的供给压力随之越来越大。基于适应性供给研究视角发现,在城市化水平、社区治理能力、社区区位等因素共同作用下,社区资源禀赋及其形塑的社区支持体系差异化程度不断扩大,这就要求城市社区养老服务开展分类式、针对性供给。研究通过对武汉城市社区的调研,以适应性供给为视角,发现新开发商品房社区适宜以市场化为导向走“企业+养老”服务供给模式;后单位制社区适宜依托内生力量发展社会性互助养老;棚改、村转居社区应注重政府行政力量的介入,优先解决老年人基础性公共福利及养老公共服务,满足老年人群体多元化需求。

关键词：社区养老服务社区资源适应性供给资源禀赋

Hepatic macrophages in homeostasis and liver diseases： from pathogenesis to novel therapeutic strategies

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Cellular & Molecular Immunology 2016年第3期13卷 316-327页

作者： Cynthia Ju frank tacke Skaggs School of Pharmacy and Pharmaceutical Sciences and Integrated Immunology University of Colorado Anschutz Medical Campus Aurora USA Department of Medicine III UniversityHospital Aachen Aachen Germany

Macrophages represent a major cell type of innate immunity and have emerged as a critical player and therapeutic target in many chronic inflammatory diseases. Hepatic macrophages consist of Kupffer cells, which are originated from the fetal yolk-sack, and infiltrated bone marrow-derived monocytes/macrophages. Hepatic macrophages play a central role in maintaining homeostasis of the liver and in the pathogenesis of liver injury, making them an attractive therapeutic target for liver diseases. However, the various populations of hepatic macrophages display different phenotypes and exert distinct functions. thus, more research is required to better understand these cells to guide the development of macrophage-based therapeutic interventions. this review article will summarize the current knowledge on the origins and composition of hepatic macrophages, their functions in maintaining hepatic homeostasis, and their involvement in both promoting and resolving liver inflammation, injury, and fibrosis. Finally, the current strategies being developed to target hepatic macrophages for the treatment of liver diseases will be reviewed.

关键词： macrophage chemokine liver fibrosis monocyte microbiome

Efficacy of chlorfenapyr against adult tribolium castaneum exposed on concrete＂ effects of exposure interval, concentration and the presence of a food source after exposure

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Insect Science 2009年第2期16卷 157-163页

作者： frank H. Arthur USDA-ARS Grain Marketing and Production Research Center Manhattan Kansas USA

Chlorfenapyr, an insecticidal pyrrole, was applied to concrete arenas at concentrations of 1. 1, 0.825, 0.55, and 0.275 g of active ingredient [AI]/m^2. Adult tribolium castaneum （Herbst）, the red flour beetle, were exposed for 2, 4, or 8 h at each concentration, then removed and held either with or without food （wheat flour） for 7 days. Survival was assessed when the beetles were removed fi＇om the exposure arenas and daily during the post- exposure period. In the presence of food, survival was high regardless of concentration and the day on which post-treatment survival was assessed, but survival did decrease as the exposure period increased from 4 to 8 h. When the beetles were not given food after exposure, survival at each concentration and exposure period declined during the 1-week post- exposure assessments. this pattern of decrease could be described by linear and non-linear equations. Results show the presence of food material greatly compromised effectiveness of the insecticide, and emphasize the importance of cleaning and sanitation in conjunction with insecticide treatments.

关键词： chlorfenapyr efficacy sanitation tribolium castaneum

Effect of hot rolling on microstructure and properties of the ZEK100 alloy

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Journal of Magnesium and Alloys 2019年第1期7卷 27-37页

作者： Amjad Javaid frank Czerwinski CanmetMAtERIALS 183 Longwood Road SouthHamiltonOntario L8P 0A5Canada

Attempts to expand manufacturing capabilities of magnesium-based sheet materials are *** as-cast ZEK100(Mg-1.2Zn-0.35Zr-0.17Nd,in wt%)magnesium alloy was subjected to hot rolling at temperatures from 350℃to 450℃using the laboratory 50 ton reversible mill with preheated rolls to manufacture the 1.5-1.7 mm thick *** rolling temperature affected the sheet properties and an increase in the rolling temperature from 250 to 450℃caused reduction of tensile strength from 257 to 228 MPa ac-companied by a reduction in tensile yield stress from 237 to 185 *** the same time,the alloy elongation increased from 17 to 21%.For the same rolling temperature range,the compressive strength reduced from 418 to 351 *** post-rolling annealing at 450℃led to reduction of both tensile and compressive properties with the largest changes corresponding to the rolling temperature of 350°*** correlation between the alloy grain size after rolling and the sheet properties was established where a reduction in grain size was accompanied by an increase of both the tensile/compressive strength and yield *** on Hall-Petch relationship and an average grain size the correlation developed in this study may be used as the prediction model for properties of the hot rolled magnesium *** results are discussed in terms of recent developments in magnesium sheet alloys and the vital role played in this process by rare earth elements.

关键词： Magnesium alloys Hot deformation Microstructure Rare earths Sheet rolling