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palaeogeography of a shallow carbonate platform:The case of the Middle to Late Oxfordian in the Swiss Jura Mountains

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Journal of palaeogeography 2015年第3期4卷 251-268页

作者： André Strasser Bernard Pittet Wolfgang Hug Department of Geosciences University of Fribourg Université Lyon 1 UMR CNRS LGLTPE 5276Campus DouaBatiment Géode69622 VilleurbanneFrance paléontologie a16 Section d'archéologie et paléontologieOffice de la cultureH?tel des Halles2900 PorrentruySwitzerland

The Oxfordian （Late Jurassic） carbonate-dominated ptatform outcropping in the Swiss Jura Mountains offers a good biostratigraphic, sequence-stratigraphic, and cyclostratigraphic framework to reconstruct changes in facies distribution at a time-resolution of 100 ka. It thus allows interpreting the dynamic evolution of this platform in much more detail than conventional palaeogeographic maps permit. As an example, a Middle to Late Oxfordian time slice is presented, spanning an interval of about 1.6 Ma. The study is based on 12 sections logged at cm-scale. The interpreted depositional environments include marginal-marine emerged ;ands, fresh-water lakes, tidal fiats, shallow lagoons, ooid shoals, and coral reefs. Although limestones dominate, marly intervals and dolomites occur sporadically. Major facies shifts are related to m-scale sea-level changes linked to the orbital short eccentricity cycle （100 ka）. The 20-ka precession cycle caused minor facies changes but cannot always be resolved. Synsedimentary tectonics induced additional accommodation changes by creating shallow basins where days accumulated or highs on which shoals or islands formed. Autocyclic processes such as lateral migration of ooid and bioclastic shoals added to the sedimentary record. CEimate changes intervened to control terrestrial run-off and, consequently, siliciclastic and nutrient input. Coral reefs reacted to such input by becoming dominated by microbialites and eventually by being smothered. Concomitant occurrence of siliciclastics anddolomite in certain intervals further suggests that, at times, it was relatively arid in the study area but there was rainfall in more northern latitudes, eroding the Hercynian substrate. These examples from the Swiss Jura demonstrate the highly dynamic and （geologically speaking） rapid evolution of sedimentary systems, in which tectonically controlled basin morphology, orbitally induced climate and sea-level changes, currents, and the ecology of the carbon

关键词： Swiss Jura Oxfordian carbonate platform facies evotution sequence stratigraphy cyclostratigraphy

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Forming Process of Strong Anisotropic Material Based on the Hydrodynamic Deep Drawing with Radial Pressure

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Journal of Materials Science & Technology 2005年第5期21卷 733-737页

作者： Joachim DANCKERT Karl Brian NIELSEN Department of Production Aalborg University Fibigerstraede 16 DK-9220Aalborg DenmarkDepartment of ProductionAalborg University Fibigerstraede 16 DK-9220Aalborg Denmark

The hydrodynamic deep drawing process enables net shape or near net shape forming of complicated sheet metal parts made from difficultly forming materials, such as aluminium or high strength steels. Based on the conventional hydrodynamic deep drawing process, a new process, hydrodynamic deep drawing process, in which radial pressure is applied to the rim of the blank, is proposed. This new process has been analysed using FEM simulations and the obtained results have been compared with the experimental results. The material used in the experiments was Al-Mg-Si alloy, and in the FEM-simulations the elastic-plastic behaviour of Al-Mg-Si alloy was modelled using Barlat＇s 89 yield criteria.

关键词： Hydroforming Hydrodynamic deep draw Simulation Aluminum alloy

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Evolution of helium bubbles in FeCoNiCr-based high-entropy alloys containing γ′ nanoprecipitates

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Chinese Physics B 2024年第7期33卷 491-500页

作者：冯婷蒋胜明胡潇天张子骏黄子敬董士刚张建 College of Energy Xiamen UniversityXiamen 361005China16

A series of high-entropy alloys(HEAs) containing nanoprecipitates of varying sizes is successfully prepared by a non-consuming vacuum arc melting *** order to study the irradiation evolution of helium bubbles in the FeCoNiCrbased HE As with γ' precipitates,these samples are irradiated by 100-keV helium ions with a fluence of 5 × 10^(20) ions/m^(2) at 293 K and 673 K,*** the samples irradiated at room temperature are annealed at different temperatures to examine the diffusion behavior of helium *** electron microscope(TEM) is employed to characterize the structural morphology of precipitated nanoparticles and the evolution of helium *** results reveal that nanosized,spherical,dispersed,coherent,and ordered L1_(2)-type Ni_(3)Ti γ' precipitations are introduced into FeCoNiCr(Ni_(3)Ti)_(0.1) HEAs by means of ageing treatments at temperatures between 1073 K and 1123 *** the ageing treatment conditions adopted in this work,γ' nanoparticles are precipitated in FeCoNiCr(Ni_(3)Ti)_(0.1) HE As,with average diameters of 15.80 nm,37.09 nm,and 62.50 nm,*** average sizes of helium bubbles observed in samples after 673-K irradiation are 1.46 nm,1.65 nm,and 1.58 nm,*** improvement in the irradiation resistance of FeCoNiCr(Ni_(3)Ti)_(0.1) HEAs is evidenced by the diminution in bubbles ***,the FeCoNiCr(Ni_(3)Ti)_(0.1) HEAs containing γ' precipitates of 15.8 nm exhibits the minimum size and density of helium bubbles,which can be ascribed to the considerable helium trapping effects of heterogeneous coherent phase ***,annealing experiments conducted after 293-K irradiation indicate that HEAs containing precipitated phases exhibits smaller apparent activation energy(E_(a)) for helium bubbles,resulting in larger helium bubble *** study provides guidance for improving the irradiation resistance of L1_(2)-strengthened high-entropy alloy.

关键词： high-entropy alloys irradiation resistance coherent precipitates helium bubbles

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Rolling of Al-SiC_p Composites

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厦门大学学报（自然科学版） 2002年第S1期41卷 103-105页

作者： Rajesh Purohit Anil Kumar Das Rakesh Sagar Mechanical Engineering Department Mechanical Engineering DepartmentMechanical Engineering Department IIT Delhi-16IIT Delhi-16IIT Delhi-16

Aluminum based metal matrix composites are offering o utstanding properties in a number of automotive and aircraft components and body structures. The major advantages of these composite materials are their high st rength to weight ratio, high stiffness, high hardness, wear resistance, low coef ficient of thermal expansion, superior dimensional stability and versatility to designer. In addition to these their isotropic properties, good forming characte ristics, easy availability of cheaper reinforcements along with the availability of comparatively low cost, high volume production methods have made them a prom ising material for future growth. Weight reduction is a major goal of automotive innovations. Lighter vehicles/ ai rcraft means less fuel consumption, reduced emissions, and improved performance. Components made from highly loaded aluminium matrix composites are attractive r elative to iron based materials because of their low density, high stiffness (eq uivalent to nodular iron) and better heat transfer characteristics. The basic co st of materials is higher with these advanced composites; however, manufacturing the part to near net shape may offset basic material costs. A good aluminium based material design can improves safety. The aluminium-based composites can give cars better acceleration and braking, improved handling, ex cellent durability, and ease of repair. Tha aluminum-based composite performs a s well or better in crash than conventional steel-structured cars because of th eir larger volume, which can absorb more crash energy. Another excellent advanta ge of Al-SiC p composite in auto design is better stability and response, and reduced noise, vibration/harshness (NHV). These advantages stem from reduced veh icle weight combined with high structural stiffness and also lead to improved st ability and turning response. In the present work Al-SiC p composite plates of 10 to 12 mm thickness w ere cast using sand casting as well as die casting process.

关键词： SiC Rolling of Al-SiC_p Composites Al

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The Sandfish's Skin:Morphology,Chemistry and Reconstruction

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Journal of Bionic Engineering 2007年第1期4卷 1-9页

作者： Werner Baumgartner Friederike Saxe Agnes Weth David Hajas Darwin Sigumonrong Jens Emmerlich Martin Singheiser Wolfgang Bhme Jochen M. Schneider Department of Cellular Neurobionics RWTH-Aachen Kopernikusstr. 16 52056 Aachen Germany Material Chemistry RWTH-Aachen Kopernikusstr. 16 52056 Aachen Germany Institute of Zoology RWTH-Aachen Kopernikusstr. 16 52056 Aachen Germany Zoologisches Forschungsmuseum Alexander Koenig (ZFMK) Adenauerallee 160 53113 Bonn Germany

The sandfish is a lizard having the remarkable ability to move in desert sand in a swimming-like fashion. The most outstanding adaptations to this mode of life are the low friction behaviour and the extensive abrasion resistance of the sandfish skin against sand, outperforming even steel. We investigated the topography, the composition and the mechanical properties of sandfish scales. These consist of glycosylated keratins with high amount of sulphur but no hard inorganic material, such as silicates or lime. Remarkably, atomic force microscopy shows an almost complete absence of attractive forces between the scale surface and a silicon tip, suggesting that this is responsible for the unusual tribological properties. The unusual glycosylation of the keratins was found to be absolutely necessary for the described phenomenon. The scales were dissolved and reconstituted on a polymer surface resulting in properties similar to the original scale. Thus, we provide a pathway towards exploitation of the reconstituted scale material for future engineering applications.

关键词： Sandfish Skink Scincus scincus tribology nanoindentation keratin abrasion

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Parallelization of Lattice Boltzmann method using MPI domain decomposition technology for a drop impact on a wetted solid wall

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International Journal of Modeling, Simulation, and Scientific Computing 2014年第2期5卷 40-52页

作者： Zhi Shang Ming Cheng Jing Lou Institute of High Performance Computing Agency for Science Technology and Research(A*STAR)1 Fusionopolis Way#16-16 ConnexisSingapore 138632

Lattice Boltzmann method(LBM)is a new attractive computational approach for simulating isothermal multi-phase flows in computational fluid dynamics(CFD).It is based on the kinetic theory and easy to be *** study aims to analyze the performance of parallel LBM programming for the incompressible two-phase flows at high density and viscosity *** this purpose,a liquid drop impact on a wetted wall with a pre-existing thin film of the same liquid is simulated by using the parallel LBM *** the simulations,the domain decomposition,data communication and parallelization of the LBM code using the message passing interface(MPI)library have been *** computational results show that the parallel LBM code exhibits a good high performance computing(HPC)on the parallel speed-up.

关键词： Dropimpact two-phaseflow Lattice Boltzmann method MPI domain decomposition HPC

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LINEAR ISOMETRIC NON-ANTICIPATIVETRANSFORMATIONS OF WIENER PROCESS

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Chinese Annals of Mathematics,Series B 2000年第1期21卷 109-114页

作者： ZORAN IVKOVIC DRAZEN PANTIC Matematički Fakultet Studentski Trg 16 11000 Beograd Yugoslavia

The necessary and sufficient conditions are given so that a non-anticipative transformation in Hilbert space is isometric. In terms of second order Wiener process, these conditions assure that a non-anticipative trans... 详细信息

关键词： Resolution of identity Separable Hilbert space Wide sense Wiener process Non-anticipative transformation

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Categorizations of Limits of Grothendieck Groups over a Frobenius P-Category

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Algebra Colloquium 2022年第4期29卷 541-594页

作者： Lluis Puig Carrer de La Cort 16 Vilafranca del PenedesFrance

In[Frobenius Categories Versus Brauer Blocks,Progress in Math.,274]and in[Ordinary Grothendieck groups of a Frobenius P-category,Algebra Colloq.18(2011)1-76],we consider suitable inverse limits of Grothendieck groups of categories of modules in characteristics p and zero,obtained from a folded Frobenius P-category(F,aut_(F)sc),which covers the case of the Frobenius P-categories associated with blocks;moreover,in[Beyond a question of Markus Linckelmann,***/abs/1507.04278]we show that a folded Frobenius P-category is actually equivalent to the choice of a regular central k^(*)-extension F^(SC) of F^(SC) ***,taking advantage of the existence of a perfect F^(SC) -locality P^(SC) we exhibit those inverse limits as the true Grothendieck groups of the categories of K_(*)G-and k_(*)G-modules for a suitable k_(*)-group G associated to the k^(*)-category P^(SC) obtained from P^(SC) and F^(SC) .It depends on a vanishing cohomology result,given with more generality intheAppendix.

关键词： Frobenius category Grothendieckgroup perfect locality

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静脉输液外渗预防及护理体会

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中国城乡企业卫生 2021年第4期36卷 196-198页

作者：盖彦彦天津市环湖医院A15、a16病区天津300350

目的控制患者静脉输液外渗产生的风险,明确在临床中可以做出及时有效的护理预防及护理操作。方法选取天津市环湖医院在2019年1月-2020年1月收治的发生过静脉输液外渗的患者作为研究对象,结合其临床资料对静脉输液发生外渗的原因进行综... 详细信息

目的控制患者静脉输液外渗产生的风险,明确在临床中可以做出及时有效的护理预防及护理操作。方法选取天津市环湖医院在2019年1月-2020年1月收治的发生过静脉输液外渗的患者作为研究对象,结合其临床资料对静脉输液发生外渗的原因进行综合分析。结果共有15例患者出现过静脉输液外渗,其中由于患者因素占40%,药物因素占30%,器械因素占20%,其他10%。结论对老年患者,无意识或半昏迷的患者需加强临床护理,主要为加强对患者或其陪伴在静脉输液注意事项方面的认识,而无意识无陪伴的患者则加强巡视观察。对药物的特性,尤其是对血管的刺激性要有认知,如甘露醇、前列地尔、更昔洛韦等药物对血管刺激性较高,对静脉输液选用的血管有一定要求。在器械方面,选用留置针而非一次性钢针,减小刺破血管的发生概率。同时,积极提高自身穿刺技术,不断学习,清楚血管的局部解剖位置。最终,以不发生静脉输液外渗为目的,减小患者的痛苦,提高患者的护理满意度。

关键词：静脉输液外渗预防

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Acupuncture inhibition on neuronal activity of spinal dorsal horn induced by noxious colorectal distention in rat

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World Journal of Gastroenterology 2005年第7期11卷 1011-1017页

作者： Pei-JingRong BingZhu Qi-FuHuang Xin-YanGao HuiBen Yan-HuaLi InsdtuteofAcupuncture ChinaAcademyofChineseMedicine16NanxiaojieofDongzhimenBeijing100700China InstituteOfAcupuncture China-AcademyofChineseM.edi_'c'.me16NanxiaojieofOongzhimenaeijing100700China DepartmentofPathophysiology BeijingUniversityofTraditionalChineseMedicineBeijing100029China InstituteofAcupuncture ChinaAcademyofChineseMedicine16NanxiaojieofDongzhimenBeijing100700China

AIM: To observe how acupuncture stimulation influences the visceral nociception in rat and to clarify the interactions between acupuncture or somatic input and visceral nociceptive inputs in the spinal dorsal horn. These will provide scientific base for illustrating the mechanism of acupuncture on visceral ***: Experiments were performed on SpragueDawley rats and the visceral nociceptive stimulus was generated by colorectal distention (CRD). Unit discharges from individual single neuron were recorded extracellularly with glass-microelectrode in L1-3 spinal dorsal *** stimulation was applied at contralateral heterotopic acupoint and ipsilateral homotopic acupoint,both of which were innervated by the same segments that innervate also the ***: The visceral nociception could be inhibited at the spinal level by the heterotopic somatic mechanical stimulation and acupuncture. The maximal inhibition was induced by acupuncture or the somatic noxious stimulation at spinal dorsal horn level with inhibiting rate of 68.61%and 60.79%, respectively (P＜0.01 and ＜0.001). In reversible spinalized rats (cervical-thoracic cold block)both spontaneous activity and responses to CRD increased significantly in 16/20 units examined, indicating the existence of tonic descending inhibition. The inhibition of acupuncture on the noxious CRD disappeared totally in the reversible spinalized rats (P＜0.001).CONCLUSION: The inputs of noxious CRD and acupuncture may interact at the spinal level. The nociceptive visceral inputs could be inhibited by acupuncture applied to hetero-topic acupoint. The effect indicates that the spinal dorsal horn plays a significant role in mediating the inhibition of acupuncture and somatic stimulation on the neuronal response to the noxious visceral stimulation and the inhibition is modulated by upper cervical cord and/or supra-spinal center.

关键词： Acupuncture Colorectal distentiori Visceral nociception Somato-visceral interactions

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