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Processing and Performance of Alumina Fiber Reinforced Alumina Composites

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Journal of Materials Science & technology 2003年第4期19卷 337-340页

作者： P.Y.Leet t.Uchijima t.Yano Research Laboratory for Nuclear Reactors Tokyo Institute of Technology2-12-1O-okayamaMeguro-kuTokyo152-8550JapanResearch Laboratory for Nuclear ReactorsTokyo Institute of Technology2-12-1O-okayamaMeguro-kuTokyo152-8550JapanResearch Laboratory for Nuclear ReactorsTokyo Institute of Technology2-12-1O-okayamaMeguro-kuTokyo152-8550Japan

Processing of alumina fiber-reinforced alumina matrix composites by hot-pressing was described. the mechanical properties of the composites fabricated by different sintering conditions including temperature and pressure have been investigated. the results indicated that the higher sintering temperature and pressure corresponded to the higher bulk density and higher maximum strength of the composite, whereas the pseudo-ductility of the composite was lower. the preliminary results of the composite with monazite-coated fibers showed that maximum strength could be improved up to 35% compared with the noncoated fiber composite in the same sintering condition. Moreover, the fracture behavior of the composite changed from completely brittle fracture to non-brittle fracture under the suitable sintering conditions. SEM observation of the fracture surface indicated that the coating worked as a protective barrier and avoided sintering of the fibers together even at high temperature and pressure during densification process.

关键词： Al2O3/Al2O3 composites Mechanical properties Hot-pressing Fiber reinforced composites

Potential recovery of precious metals from waste laptops in Jordan

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Rare Metals 2015年第7期34卷 517-521页

作者： Mohammad A.t.Alsheyab Program Manager of Civil and Environmental Engineering Qatar Foundation

to achieve a sustainable development in the electronic and electrical equipment(EEE) industry, it is necessary to protect the available natural *** addition, to satisfy the increasing demand on EEE, it is necessary to provide alternative sources of raw *** this paper, laptops were imported to Jordan in 2011 as an example to show the potential recovery of metals and precious metals from high grade waste electronic and electrical equipment by conducting a mass flow rate analysis using the StAN *** results show that considerable amounts of gold, silver, cobalt, palladium,and copper could be *** will reduce the amounts needed from primary natural resources and offset the CO2 emissions produced from mining the primary raw material resources.

关键词： Precious metals Laptops Waste of electronic and el

A　Possible　Origin　of　Dark　Energy

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Chinese Physics Letters 2004年第6期21卷 1187-1188页

作者： t.D.Lee PhysicsDepartment ColumbiaUniversityNewYorkNY10027USA

We discuss the possibility that the existence of dark energy may be due to the presence of a spin zero field φ(x), either elementary or composite. In the presence of other matter field, the transformation φ(x)→φ(x) + constant can generate a negative pressure, like the cosmological constant. In this picture, our universe can be thought as a very large bag, similar to the much smaller MIt bag model for a single nucleon.

关键词： Gravitation and cosmology Particle physics and field theory Astrophysics and astroparticles

On the Indeterminacy in Hardness of Shape Memory Alloys

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Journal of Materials Science & technology 2004年第6期20卷 700-702页

作者： F.t.Cheng DeDartment of Applied Phvsics

the present communication addresses an interesting problem related to the indeterminacy in hardness of superelastic Niti reported by Xu et al. the origin of the indeterminacy is attributed to the inadequacy of the conventional Vickers hardness testing measurement which does not record elastic deformation, and thus the indeterminacy may be removed with suitable techniques. Concepts of hardness in relation to deformation are clarified. Recommendations for measuring the hardness of Niti and other elastic-plastic materials are suggested, together with comments on the advantages and disadvantages of each of these methods.

关键词： Hardness Elastic-plastic materials Elastic recovery Vickers microhardness test Niti SMA

Safeguarding our future by protecting biodiversity

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Plant Diversity 2020年第4期42卷 221-228页

作者： Richard t.Corlett Center for Integrative Conservation Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan666303China Center of Conservation Biology Core Botanical GardensChinese Academy of SciencesMenglaYunnan666303China

the Anthropocene is marked by twin crises:climate change and biodiversity *** change has tended to dominate the headlines,reflecting,in part,the greater complexity of the biodiversity *** itself is a difficult *** plants dominate the global biomass and terrestrial arthropods probably dominate in terms of numbers of species,but most of the tree of Life consists of single-celled eukaryotes,bacteria,and *** plants provide a huge variety of products and services to people,ranging from those that are species-specific,such as food,medicine,and genetic resources,to many which are partly interchangeable,such as timber and forage for domestic animals,and others which depend on the whole community,but not on individual species,such as regulation of water supply and carbon *** use of information from remote sensing has encouraged a simplified view of the values of nature's contributions to people,but this does not match the way most people value *** can currently estimate the proportion of species threatened by human impacts only for a few well-assessed groups,for which it ranges from 14%(birds)to 63%(cycads).Less than 8%of land plants have been assessed,but it has been estimated that 30e44%are threatened,although there are still few(0.2%)well-documented *** for improving protection of biodiversity include:improving the inventory,with surveys focused on geographical areas and taxonomic groups which are under-collected;expanding the protected area system and its representativeness;controlling overexploitation;managing invasive species;conserving threatened species ex situ;restoring degraded ecosystems;and controlling climate *** Convention on Biological Diversity(CBD)COP15 and the United Nations Framework Convention on Climate Change(UNFCCC)COP26 meetings,both postponed to 2021,will provide an opportunity to address both crises,but success will require high ambition from all participants.

关键词： Anthropocene Climate change Conservation Ecosystem services Values

Solution for Energies and Mixing of two 0^+ States in ^(10)He

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Chinese Physics Letters 2016年第9期33卷 27-28页

作者： H.t.Fortune Department of Physics and Astronomy University of Pennsylvania

Using results from various reactions that populate 10He, I conclude that the ground state has E2n = 1.07（7） MeV and the excited 0＋ state is in the region of 2.1-3.1 MeV. the amount of the （sd）2 component in the g... 详细信息

关键词： of is on for that Solution for Energies and Mixing of two 0 States in He

Hemostatic agents for prehospital hemorrhage control: a narrative review

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Military Medical Research 2020年第4期7卷 444-463页

作者： Henry t.Peng Defence Research and Development Canada Toronto Research Centre1133 Sheppard Avenue WestTorontoON M3K 2C9Canada

Hemorrhage is the leading cause of preventable death in combat trauma and the secondary cause of death in civilian trauma.A significant number of deaths due to hemorrhage occur before and in the first hour after hospital arrival.A literature search was performed through PubMed,Scopus,and Institute of Scientific Information databases for English language articles using terms relating to hemostatic agents,prehospital,battlefield or combat dressings,and prehospital hemostatic resuscitation,followed by cross-reference *** were screened to determine relevance and whether appropriate further review of the original articles was *** on these findings,this paper provides a review of a variety of hemostatic agents ranging from clinically approved products for human use to newly developed concepts with great potential for use in prehospital *** hemostatic agents can be administered either systemically or locally to stop bleeding through different mechanisms of *** of current hemostatic products and further directions for prehospital hemorrhage control are also discussed.

关键词： Hemostatic agent Hemorrhage control trauma

New Naturally Occurring Product Extract as Corrosion Inhibitor for 316 Stainless Steel in 5% HCl

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Journal of Materials Science & technology 2004年第4期20卷 463-466页

作者： t.Y.Soror Chemistry Department Faculty of Science Cairo University Cairo Egypt

Medipolymorphol, a new sterol isolated from the whole plant of Medicago polymorpha Roxb was used as corrosion inhibitor for 316 stainless steel in 5% HCI at room temperature. Electrochemical techniques have been found to be reliable in evaluating corrosion characteristics of the system. Several techniques have been used including tafel, linear polarization, potentiodynamic polarization, and open circuit potential (OCP) studies. the additives simultaneously deaccelerated the anodic process, intensified the cathodic process and provided a stable passive state, giving good inhibition efficiencies to stainless steel electrodes. In addition, adsorption isotherm have been fitted for the inhibitor under investigation.

关键词： Medipolymorpho] Plant extract Stainless steel HCl Corrosion inhibitor

Ion Heating from Nonlinear Landau Damping of High Mode Number toroidal Alfvén Eigenmodes

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Plasma Science and technology 2015年第7期17卷 534-538页

作者： t.S.HAHM Department of Nuclear Engineering Seoul National University

Bulk ion heating rate from nonlinear Landau damping of high mode number toroidal Alfven Eigenmodes （tAEs） is calculated in the frame work of weak turbulence theory. the heating rate is lower than the nonlinear spect... 详细信息

关键词： Alfven wave nonlinear Landau damping toroidal Alfven eigenmode