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Strain-Rate Dependency of a Unidirectional Filament Wound Composite under Compression

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Computer modeling in Engineering & Sciences 2023年第12期137卷 2149-2161页

作者： Stepan Konev Victor A.Eremeyev Hamid m.Sedighi Leonid Igumnov Anatoly Bragov Aleksandr Konstantinov Ayaulym Kuanyshova Ivan Sergeichev Skolkovo Institute of Science and Technologies Center for Materials TechnologiesMoscowRussia National Research Lobachevsky State University of Nizhny Novgorod Nizhny NovgorodRussia Dipartimento di Ingegneria Civile Ambientale e Architettura(DICAAR)Universitàdegli Studi di CagliariCagliari(CA)Italy mechanical Engineering Department Faculty of EngineeringShahid Chamran University of AhvazAhvazIran Drilling Center of Excellence and Research Center Shahid Chamran University of AhvazAhvazIran

This article presents the results of experimental studies concerning the dynamic deformation and failure of a unidirectional carbon fiber reinforced plastic(T700/LY113)under *** test samples were manufactured through the filament winding of flat *** establish the strain rate dependencies of the strength and elastic modulus of the material,dynamic tests were carried out using a drop tower,the Split Hopkinson Pressure bar.method,and standard static *** samples were loaded both along and perpendicular to the direction of the reinforcing *** applicability of the obtained samples for static and dynamic tests was confirmed through finite elementmodeling and the high-speed imaging of the deformation and failure of samples during *** a result of the conducted experimental studies,static and dynamic stress-strain curves,time dependencies of deformation and the stress and strain rates of the samples during compression were *** on these results,the strain rate dependencies of the strength and elasticity modulus in the strain rate range of 0.001-6001/s are *** is shown that the strain rate significantly affects the strength and deformation characteristics of the unidirectional carbon fiber composites under *** increase in the strain rate by 5 orders of magnitude increased the strength and elastic modulus along the fiber direction by 42%and 50%,*** loading resulted in a strength and elastic modulus increase by 58%and 50%,*** average strength along the fibers at the largest studied strain rate was about *** obtained results can be used to design structural elements made of polymer composite materials operating under dynamic shock loads,as well as to build models of mechanical behavior and failure criteria of such materials,taking into account the strain rate effects.

关键词： High strain rate composites filament winding dynamic strength Split Hopkinson Pressure bar compression

依诺肝素对具有流产与血栓形成倾向妇女晚期妊娠并发症及新生儿结局的影响:Live-Enox研究结果

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世界核心医学期刊文摘（妇产科学分册） 2006年第2期2卷 24-24页

作者： Brenner B. bar.J. Ellis m. 李跃萍 Dr.Thrombosis and Hemostasis Unit Rambam Medical Center PO Box 9602 Haifa 31096 Israel

Women with thrombophilia and a history of recurrent pregnancy loss have poor pregnancy outcomes. Prophylaxis with enoxaparin 40 mg/day or 80 mg/day resulted in favorable gestational and neonatal outcomes.

关键词：血栓形成倾向新生儿结局 Live-Enox 晚期妊娠依诺肝素妊娠结局预防性给药流产史

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Experimental Studies on Critical Heat Flux in a Uniformly Heated Vertical Tube at Low Pressure and Flowrates

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Journal of Energy and Power Engineering 2012年第1期6卷 60-69页

作者： Husham m. Ahmed Department of mechanical Engineering Gulf University P.O.Box： 26489 Manama Bahrain

Investigations into critical beat flux at low flow and pressure conditions are of particular interest when predicting the nuclear reactor core behavior during Loss of Coolant accident （LOCA）. Therefore, critical heat flux （CHF） has been investigated in a uniformly heated vertical round tube at two low system pressures and six low water flowrates. The results have been compared with two correlations which have different approaches and CHF look-up table. Good agreements have been obtained for the three comparisons at the lower sets of mass fluxes. The Bowring correlation was found to be the best to correlate the experimental results with Root mean Square Error RmSE of 0.54% and 0.56% for the 5 bar.and 15 bar.system pressure respectively. A comparisons with the Shim and Lee correlation yielded RmSE of 0.23% and 5.74% for the two system pressure respectively. When the look-up table of Groeneveld et al. was used, RmES of 0.55% and 25.2% was obtained for the two system pressure respectively.

关键词： Critical heat flux dryout burnout subcooled boiling LOCA.

Tensegrities and Tensioned Structures

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Journal of Architectural Environment & Structural Engineering Research 2020年第3期3卷 10-16页

作者： mªDolores Alvarez Elipe CEIPSO Salvador Dalí Spain

“Push-and-pull”efficient structures have been inconceivable between XVIII *** is because of the incapacity of obtain an efficient behaviour of tensioned *** XVIII centuries,architecture developed some structural knowledge generating novel structural forms in the architecture and engineering that were not known *** and tensioned structures were studied due to the knowledge of geometry and *** investigations about tensegrities and tensioned structures have been developed since that *** are bar.and cable structures that work only in compression or tension *** and cables are balanced,but in appearance the growth is *** of deployable structures are based on tensegrity *** research is focused in presenting a summary of tensegrities and tensioned architectures that have been used in the structural design of novel *** research of adequate materials to tension efforts will be crucial in this *** investigation presents an important state of the art that provides technical solutions to apply on novel architectures based on tensegrities and tensioned *** research is useful to produce the current constructive solutions based on these constructive systems.

关键词： Tensegrity Tensioned Geometry Structure Compression Tension Effort

New constraints on the P-T path of HT/UHT metapelites from the Highland Complex of Sri Lanka

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Geoscience Frontiers 2017年第6期8卷 1405-1430页

作者： P.L.Dharmapriya Sanjeewa P.K.malaviarachchi L.m.Kriegsman Andrea Galli K.Sajeev Chengli Zhang Postgraduate Institute of Science University of Peradeniya20400Sri Lanka Department of Geology Faculty of ScienceUniversity of Peradeniya20400Sri Lanka Naturalis Biodiversity Center Darwinweg 2NL-2333 CR LeidenThe Netherlands Department of Earth Sciences Utrecht UniversityBudapestlaan 4NL-3584 CD UtrechtThe Netherlands Department of Earth Sciences ETH ZurichSonnegstrasse 5CH-8092 ZurichSwitzerland Centre for Earth Sciences Indian Institute of ScienceBangalore 560012India Key Laboratory of Continental Dynamics of Northwest University Department of GeologyNorthwest UniversityXi’an 710069China

We report here rare evidence for the early prograde P-Tevolution of garnet-sillimanite-graphite gneiss(khondalite)from the central Highland Complex,Sri *** types of garnet porphyroblasts(Grt_1,Grt_2,Grt_3 and Grt_4)are observed in the rock with specific types of inclusion *** Grt_3 shows evidence for non-coaxial *** the information shows a sequence of main inclusion phases,from old to young:oriented quartz inclusions at core,staurolite and prismatic sillimanite at mantle,kyanite and kyanite pseudomorph,and biotite at rim in Grt_1;fibrolitic sillimanite pseudomorphing kyanite±corundum,kyanite,and spinel+sillimanite after garnet+corundum in Grt_2;biotite,sillimanite,quartz±spinel in Grt_3;and ilmenite,rulite,quartz and sillimanite in Grt_*** pre-melting,original rock composition was calculated through stepwise re-integration of melt into the residual,XRF based composition,allowing the early prograde metamorphic evolution to be deduced from petrographical observations and *** earliest recognizable stage occurred in the sillimanite field at around 575℃ at 4.5 *** collision associated with Gondwana amalgamation led to crustal thickening along a P-T trajectory with an average dP/dT of ~30 bar.℃ in the kyanite field,up to ~660℃ at 6.5 kbar.before crossing the wet-solidus at around 675 ℃ at 7.5 *** highest pressure occurred at P > 10 kbar.and T around 780℃ before prograde decompression associated with further *** 825℃ and 10.5 kbar.the rock re-entered into the sillimanite *** temperature peaked at 900℃ at ca.9-9.5 *** near-isobar.c cooling led to the growth of Grt_4 and rutile at T ~880℃.Local pyrophyllite rims around sillimanite suggest a late stage of rehydration at TmS of the khondalite yielded two concordant ^(206)Pb/^(238)U age groups with mean values of 542±2 ma(mSWD=0.24,Th/U=0.01-0.

关键词： Prograde evolution melt re-integration Highland Complex Sri Lanka UHT granulites

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Smaller bar.spacings in a Nordmøre grid reduces the bycatch of redfish(Sebastes spp.)in the offshore Northern shrimp(Pandalus borealis)fishery of eastern Canada

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Aquaculture and Fisheries 2023年第6期8卷 661-671页

作者： Tomas Araya-Schmidt Shannon m.Bayse Paul D.Winger Colin H.Frank Centre for Sustainable Aquatic Resources Fisheries and Marine InstituteMemorial University of NewfoundlandSt.John’sNLA1C 5R3Canada

The offshore Northern shrimp(Pandalus borealis)bottom trawl fishery in eastern Canada currently uses 22 and 28 mm bar.spacing Nordmøre grids to limit bycatch from using small mesh ***,a recent rebound of juvenile redfish(Sebastes spp.),that can pass through the grids,has greatly increased *** address this concern,this study investigated the effectiveness of 17 and 15 mm bar.spacing Nordmøre grids in a twin-trawl(paired)configuration against the traditional 22 mm bar.spacing *** selectivity analyses showed that the 17 and 15 mm grids resulted in no significant reduction in shrimp catch across all length *** 17 mm grid significantly reduced redfish bycatch for all length classes and the 15 mm grid significantly reduced redfish bycatch for individuals larger than 95 mm total *** redfish entered the codend with the experimental grids,however,the overlap in width between redfish and Northern shrimp limits the overall sorting efficiency of the grids,leaving some redfish still vulnerable to capture.

关键词： Size selectivity Twin trawling Catch comparison Bycatch reduction device

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先天性白内障手术后早期较大散光的向量分析

世界核心医学期刊文摘(眼科学分册) 2006年第1期 48-48页

作者： bar.Sela S.m. bar.quet I.S. Spierer A. 曹绪胜 Goldschleger Eye Institute Sheba Medical Center 52621 Tel-Hashomer Israel

Background: Corneal astigmatism is a well-documented finding after cataract surgery. Postoperative astigmatism is of greater importance in children than in adults, because of its adverse effect on vision development and the risk of amblyopia. The purpose of this study was to evaluate refractive outcomes in eyes-which had high early postoperative astigmatism after congenital cataract surgery. methods: We retrospectively reviewed the charts of 74 children (112 eyes), who underwent congenital cataract extraction with intraocular lens implantation, using limbal incision, scleral tunnel, or clear corneal incision. Thirty-two eyes of 28 children, aged 2 months to 11 years, had astigmatism of 3.0 diopters (D) or more when assessed 1 week after surgery. Changes in cylinder vector, spherical equivalent (SEQ) and defocus equivalent (DEQ) between 1 week and 5 months postoperatively were calculated for each group. Results: mean SEQ and DEQ were 0.7± 3.5 D and 5.1± 2.8 D, respectively, at 1 week postoperatively-and -0.2± 3.4 D and 3.1± 2.3 D, respectively, at 5 months postoperatively in the three groups. DEQ levels showed a significant reduction during the 5-month follow-up period (P mean astigmatism vector was 2.9± 3.3 D× 93° in all the three groups 1 week postoperatively-and 0.2± 1.1 D× 153° at 5 months after surgery. A significant change during 5-month follow-up in cylinder vector (P < 0.02) and SEQ (P=0.01) was found after operations using scleral tunnel technique. Conclusion: Children-who underwent congenital cataract surgery by different surgical techniques showed a significant spontaneous reduction in DEQ values. A significant change in cylinder vector and SEQ was found after operations using scleral tunnel technique.

关键词：先天性白内障手术后向量患儿巩膜隧道术后早期

Additive friction stir deposition of AZ31B magnesium alloy

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Journal of magnesium and Alloys 2022年第9期10卷 2404-2420页

作者： Sameehan S.Joshi Shreyash m.Patil Sangram mazumder Shashank Sharma Daniel A.Riley Shelden Dowden Rajarshi Banerjee Narendra B.Dahotre Department of materials Science and Engineering University of North Texas3940 N Elm StDentonTX 76207USA Center for Agile and Adaptive Additive manufacturing University of North Texas3940 N Elm StDentonTX 76207USA

The current work explored additive friction stir deposition of AZ31B magnesium alloy with the aid of mELD?***31B magnesium bar.stock was fed through a hollow friction stir tool rotating at constant velocity of 400 rpm and translating at linear velocity varied from 4.2 to 6.3 mm/s.A single wall consisting of five layers with each layer of 140×40×1 mm^(3)dimensions was deposited under each processing ***,phase,and crystallographic texture evolutions as a function of additive friction stir deposition parameters were studied with the aid of scanning electron microscopy including electron back scatter diffraction and X-ray *** feed material and additively produced samples consisted of theα-mg *** additively produced samples exhibited a refined grain structure compared to the feed *** feed material appeared to have a weak basal texture,while the additively produced samples experienced a strengthening of this basal *** additively produced samples showed a marginally higher hardness compared to the feed *** current work provided a pathway for solid state additive manufacturing of mg suitable for structural applications such as automotive components and consumable biomedical implants.

关键词： Additive friction stir deposition magnesium alloys Additive manufacturing Thermomechanical processing materials processing Solid state additive manufacturing

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Effect of Sustained Deficit Irrigation on Stem Water Potential of Navel Oranges in Jordan Valley

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Journal of Agricultural Science and Technology(B) 2011年第8期1卷 1152-1160页

作者： N. m. Bani Hani m. R. Shatanawi Water and Irrigation Program National Center for Agricultural Research and Extension P.O. Box 939 Baqa 19381 Jordan Faculty of Agriculture University of Jordan P.O. Box 13042 Amman Jordan

Research was conducted to find the relationship between deficit irrigation treatments （DIT） and stems water potential. The study was conducted on 14 years old navel orange trees grafted on sour oranges for the growing season 2006/2007 at a private farm in the Northern part of Jordan Valley （latitude： 32° 50′ N, longitude： 32° 50′ E, altitude： -254 m）. Three levels of irrigation treatments （IT） were applied; namely 100%, 75% and 50% of reference evapotranspiration, representing over irrigation （OIT）, full irrigation （FIT）, and deficit irrigation （DIT）, respectively. A drip irrigation using one irrigation source line with drippers spaced 0.5 m having average discharge of 2.3 L/hr at pressure 1.5 bar. was used. Stem water potential （SWP） at 100% over irrigation treatment （OIT） of navel orange trees had less negative value during the irrigation seasons （-1.57 mPa）, whereas the highest negative value （-2.17 mPa） occurred at 50% deficit irrigation treatment （DIT）.

关键词： Navel orange deficit irrigation actual evapotranspiration crop coefficient stems water potential.