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THE PHYSICAL SIMULATION ON EXTRUSION PROCESS Of GLASS fIBER COMPOSITE wIRE COATED BY LEAD

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Acta Metallurgica Sinica(English Letters) 2004年第6期17卷 940-944页

作者： H.f.Sun w.B.fang f.Han w.X.He E.D.wang SchoolofMaterialsScienceandEngineering HarbinInstituteofTechnologyHarbin150001China

The method of manufacturing the composite wire by extruding lead to coated glass fiber is described. The different composite wire that diameter is from 0.5 to 1.0mm has been produced by two kinds of different extruding technology (getting wire along horizontal direction and getting wire along perpendicular direction). The optimal extruding techno- logical parameter has been given in different extruding technology by the physical simulation (H: 300℃, 550kN, 0.16mm. P: 300℃, 215kN, 0.16mm). The effect on the coating speed by other extruding technological parameters in the different extruding technology has been discussed. The extruding temperature and extruding force is higher, the coating speed is faster. It has been pointed, that the affection on the extruding technology by the extruding temperature has also behaved as the extruding temperature rising up spontaneously. The reason for exiting the minimum extruding force and maximum extruding force also has been discussion in this paper. It is also important to the extruding process and coating speed that is the coating clearance.

关键词： composite lead glass fiber coating physical simulation

Compressive and cyclic flexural response of double-hooked-end steel fiber reinforced concrete

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frontiers of Structural and Civil Engineering 2022年第9期16卷 1104-1126页

作者： Demewoz w.MENNA Aikaterini S.GENIKOMSOU Mark f.GREEN Department of Civil Engineering Queen’s UniversityKingstonON K7L 3N6Canada

Recent developments on high-performance double-hooked-end steel fibers have enhanced the wide applications of steel fiber reinforced concrete(SfRC).This study presents the compressive properties and the cyclic flexural performance of the SfRC that were experimentally *** different double-hooked-end steel fibers at 0.25%,0.5%,0.75%,and 1%volume fractions were *** fiber types had similar length to diameter ratios,while the first two fiber types had similar anchorage mechanisms(4D)and tensile strength and the third type had different anchorage mechanism(5D)and a higher tensile *** increased volumetric ratio of the fibers increased the post-peak compressive strain(ductility),the tensile strength,and the cyclic flexural strength and cumulative energy dissipation characteristics of the *** the 4D fibers,the mixtures with the larger steel fibers showed higher flexural strength and more energy dissipation compared to the SfRCs with smaller size *** 1%steel fiber dosage,4D and 5D specimens showed similar cyclic flexural ***,a 3D finite element model that can predict the monotonic and cyclic flexural responses of the double-hooked-end SfRC was *** calibration process considered the results obtained from the inverse analysis to determine the tensile behavior of the SfRC.

关键词： steel fiber reinforced concrete fiber geometry cyclic loading energy dissipation finite element modeling inverse analysis

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高保真度立体声手册

高保真度立体声手册

Reliability of quasi integrable and non-resonant Hamiltonian systems under fractional Gaussian noise excitation

作者： w.f.·博伊斯(w.f. Boyce)

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Acta Mechanica Sinica 2020年第4期36卷 902-909页

作者： Q.f.Lu w.Q.Zhu M.L.Deng Department of Mechanics State-Key Laboratory of Fluid Power and Mechatronic SystemsZhejiang UniversityHangzhou 310027China

The reliability of quasi integrable and non-resonant Hamiltonian system under fractional Gaussian noise(fGn)excitation is *** rather flat fGn power spectral density(PSD)in most part of frequency band,the fGn is innovatively regarded as a wide-band ***,the stochastic averaging method for quasi integrable Hamiltonian systems under wide-band noise excitation is applied to reduce 2n-dimensional original system into n-dimensional averaged ltd stochastic differential equations(SDEs).Reliability function and mean first passage time are obtained by solving the associated backward Kolmogorov equation and Pontryagin *** validity of the proposed procedure is tested by applying it to an example and comparing the numerical results with those from Monte Carlo simulation.

关键词： Reliability fkst passage time Quasi integrable and non-resonant Hamiltonian systems fractional Gauss noise

Merging bound states in the continuum in an open acoustic resonator

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin Jia Artem S.Pilipchuk Sibo Huang Chen Shen Almas f.Sadreev Yong Li Andrey E.Miroshnichenko School of Physics and Electronic Sciences East China Normal University Institute of Acoustics Tongji University L.V.Kirensky Institute of Physics Department of Mechanical Engineering Rowan University School of Engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and friedrich-wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances

Enhanced Mechanical Properties of friction Stir welded 5083Al-H19 Joints with Additional water Cooling

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Journal of Materials Science & Technology 2017年第9期33卷 1009-1014页

作者： B.B.wang f.f.Chen f.Liu w.G.wang P.Xue Z.Y.Ma School of Mechanical Engineering Liaoning Shihua University Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

3-mm-thick 5083Al-H19 rolled plates were friction stir welded(fSw) at tool rotation rates of 800 and200 rpm with and without additional water cooling. with decreasing the rotation rate and applying water cooling, softening in the fSw joint was significantly reduced. At a low rotation rate of 200 rpm with additional water cooling, almost no obvious softening was observed in the fSw joint, and therefore a fSw5083Al-H19 joint with nearly equal strength to the base material(BM) was obtained. furthermore, the grains in the nugget zone were considerably refined with reducing the heat input and ultrafine equiaxed grains of about 800 nm were obtained in the lowest heat input condition. This work provides an effective method to achieve high property fSw joints of precipitate-hardened and work-hardened Al alloys.

关键词： friction stir welding Aluminum alloy water cooling Microstructure Mechanical property

High energy barriers for edge dislocation motion in body-centered cubic high entropy alloys

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npj Computational Materials 2021年第1期7卷 1017-1025页

作者： R.E.Kubilay A.Ghafarollahi f.Maresca w.A.Curtin Laboratory for Multiscale Mechanics Modeling(LAMMM) Institute of Mechanical EngineeringEPFLLausanneSwitzerland engineering and technology institute groningen faculty of science and Engineeringuniversity of groningengroningenthe netherlands

Recent theory proposes that edge dislocations in random body-centered cubic(BCC)high entropy alloys have high barriers for motion,conveying high strengths up to high ***,the energy barriers for edge motion are computed for two model alloys,NbTaV and MoNbTaw as represented by interatomic potentials,using the Nudged Elastic Band method and compared to theoretical *** average magnitude of the barriers and the average spacing of the barriers along the glide direction agree well with the analytical theory,with no adjustable *** evolution of the barriers versus applied stress is modeled,and the mean strength is in reasonable agreement with the predicted zero-temperature *** findings validate the analytic theory.A reduced analytic model based on solute misfit volumes is then applied to Hf-Mo-Nb-Ta-Ti-Zr and Mo-Nb-Ta-Ti-Vw alloys,rationalizing the observed significant strength increases at room temperature and 1000℃upon addition of solutes with large misfit into a base *** analytic theory for edge motion is thus a powerful validated tool for guiding alloy selection.

关键词： alloys strength alloy

Evidence for the ef?cacy and safety of herbal weight loss preparations

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Journal of Integrative Medicine 2019年第2期17卷 87-92页

作者： Rachael farrington Ian f.Musgrave Roger w.Byard Adelaide Medical School The University of Adelaide forensic Science SA

Rising rates of obesity across the globe have been associated with an increase in the use of herbal preparations for weight control. However, the mechanisms of action for these substances are often not known,as is the potential for interaction with other herbal preparations or prescription pharmaceutical drugs. To investigate the reported efficacy and safety of herbal weight loss preparations, we conducted a review of the literature focusing on herbs that are most commonly used in weight loss preparations, specifically,Garcinia cambogia, Camellia sinensis, Hoodia gordonii, Citrus aurantium and Coleus forskohlii. There was no clear evidence that the above herbal preparations would cause sustained long-term weight loss in humans in the long term. Serious illness and even death have occasionally resulted from the use of herbal weight loss preparations. few clinical trials have been undertaken to evaluate the efficacy and/or safety of herbal weight loss preparations. In addition, potential issues of herb–herb and herb–drug interactions are often not considered. Regulation of these products is much less rigorous than for prescription medications, despite documented cases of associated hepatotoxicity.

关键词： weight loss Hepatotoxicity Complementary medicine Traditional Chinese medicine

The Alpe Arami Story: Triumph of Data over Prejudice

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Journal of Earth Science 2010年第5期21卷 731-743页

作者： Harry w Green II Larissa f Dobrzhinetskaya Krassimir N Bozhilov Institute of Geophysics and Planetary Physics Department of Earth Sciences University of California at Riverside Riverside CA92521 USA Department of Earth Sciences University of California at Riverside Riverside CA92521 USA

The Alpe Arami garnet peridotite of the Southern Swiss Alps is associated with eclogites and included within quartzofeldspathic gneisses. Controversy has swirled around the depth of origin of this massif since the 1970s when application of the newly-developed technique of thermobarometry suggested a depth of last equilibration of greater than 120 kin. Such controversy accelerated in 1996 when we reported microstructural evidence of extensive precipitation of ilmenite and spinel from olivine and proposed a much greater depth of origin. Subsequent experiments showed that it was possible to dissolve the observed amount of TiO2 in olivine, but only at depths in excess of 300 kin, agreeing with the earlier proposal. In 1999 we added new, independent, evidence concerning exsolution of high-pressure clinoenstatite from diopside that in-and-of-itself required a depth of origin in excess of 250 km. Subsequently, we also added evidence from the surrounding eclogites of very high pressures and experimental evidence that the pyroxenes included in the amoeboid garnets of this rock had exsolved from a majoritic parent at perhaps even greater pressures. In refutation of the first two of these observations, suggestions were made that （i） we had made a serious error in our estimate of how much ilmenite was present in olivine （and therefore how much TiO2 had been dissolved in olivine）; （ii） the ilmenite had not been exsolved from olivine but former titanian clinohumite had been present and broke down to yield the ilmenite; （iii） the pyroxene exsolved from diopside had been high-temperature clinoenstatite. In all three of these cases, the alternatives offered were claimed to be accommodated at low pressures. Here we review the essence of this controversy and show that the only scenario that can explain all of the data is the one that we originally proposed; indeed, the more recent data have strongly supported that interpretation and pushed the minimum origin of the massif to depths ap

关键词： Alpe Arami TiO2 in olivine high-pressure clinoenstatite deep exhumation.