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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

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

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.

Strain rate sensitivity of a 1.5 GPa nanotwinned steel

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Journal of Iron and Steel Research International 2021年第11期28卷 1352-1356页

作者： R.D.Liu Y.Z.Li L.Lin C.P.Huang Z.H.Cao m.X.Huang Iron and Steel Research Institute Ansteel GroupAnshan 114021LiaoningChina Department of mechanical Engineering The University of Hong KongHong Kong 999077China

Two distinct regimes of strain rate sensitivity on yield strength are found in a high-strength nantwinned *** yield strength increases from 1410 to 1776 mPa when the strain rate increases from 10–3 to 1400 *** is proposed from the measured small activation volume that the yielding of the nanotwinned steel at higher strain rates is governed by the dislocation bowing out from the carbon *** lower strain rates,however,the yielding is controlled by the continuous re-pinning of dislocations due to the fast diffused carbon atoms,which leads to the relative insensitivity of yield strength to the strain rate.

关键词： Nanotwinned steel Strain rate sensitivity Hokinson tensile bar Twinning Twinning-induced plasticity steel

mICROENDOSCOPIC SPECTRAL ImAGING AS A TOOL FOR SmALL DUCTUAL DIAGNOSTICS:PRELImINARY EXPERIENCE

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Journal of Innovative Optical Health Sciences 2012年第3期5卷 64-70页

作者： A.DOUPLIK W.L.LEONG A.m.EASSON S.DONE B.C.WILSON A.SHAHmOON Z.ZALEVSKY Department of Physics Ryerson University 350 Victoria StreetToronto M5B 2K3Canada School of Advanced Optical Technologies(SAOT)Friedrich-Alexander Erlangen-Nuremberg University ErlangenGermany Ontario Cancer Institute University Health Network TorontoCanada Xillix Ltd TorontoCanada medical Photonics Engineering Group(mPEG)Chair of Photonics Technologies Friedrich-Alexander Erlangen-Nuremberg University ErlangenGermany Department of Surgical Oncology Princess margaret Hospital University Health Network TorontoCanada Department of medical Biophysics University of Toronto TorontoCanada Faculty of Engineering bar.Ilan University Ramat GanIsrael

A technical feasibility of autofluorescence ductoscopy in breast milk ducts as blood vessels phantoms has been assessed as *** tumor can be clearly identified through the milk *** also present the operation principle as well as the preliminary experimental results of a new type of microsize multicorefiber that enables imaging through blood vessel *** of a manipulated microwire through a drilled phantom is presented.

关键词： Cancer margin delineation endoscopy microendoscopy autofluorescence imaging surgical guidance multicorefibers

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.

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黏土中静压沉桩离心模型

工程科学学报 2018年第3期40卷 285-292页

作者：李雨浓 bar.y m Lehane 刘清秉燕山大学建筑工程与力学学院秦皇岛066004 西澳大学土木工程与资源学院珀斯6009 中国地质大学武汉三峡研究中心武汉430074

采用西澳大学室内鼓轮式离心机,在预先固结的高岭黏土中开展不同离心力场（50g,125g及250g,g为重力加速度）条件下的模型压桩试验、T-bar.验和静力触探试验,分析了模型桩在贯入过程、静置稳定过程中桩身径向应力（σr）的变化规律,并... 详细信息

采用西澳大学室内鼓轮式离心机,在预先固结的高岭黏土中开展不同离心力场（50g,125g及250g,g为重力加速度）条件下的模型压桩试验、T-bar.验和静力触探试验,分析了模型桩在贯入过程、静置稳定过程中桩身径向应力（σr）的变化规律,并对后期桩体拉伸载荷阶段的径向应力变化值（Δσr）及桩侧摩阻力变化情况行了探讨,揭示了在不同超固结比（OCRs）黏土中静压桩侧摩阻力的演变特性.在此基础上,通过两种经验公式方法对桩侧摩承载力进行了预测计算和对比分析.研究结果表明：沉桩过程中桩端相对高度（h/B）对桩身径向应力的发展变化有很大的影响,桩身不同位置（h/B）的总径向应力对同一贯入深度而言,存在桩侧径向应力退化现象;基于静力触探试验提出的经验方法,能有效考虑静力触探锥端阻力（qt）和桩端相对高度（h/B）因素的影响,将其应用于黏土沉桩时桩侧摩阻力的预测,可取得与试验实测结果较吻合的结果.研究成果对软土地区静压桩施工与承载力设计具有一定的工程指导意义.

关键词：静压桩径向应力黏土桩侧承载力离心模型

High harmonic generation and ionization effects in cluster targets

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High Power Laser Science and Engineering 2014年第4期2卷 39-45页

作者： m.Aladi I.mrton P.Rcz P.Dombi I.B.Fldes Wigner Research Centre for Physics of the Hungarian Academy of Sciences Association EURATOM HASH-1121 Budapest Konkoly-Thege u.29-33 Hungary

High harmonic generation in gas jets was investigated in different gases up to more than 14 bar.backing pressure. The observation of increase of harmonic intensity with increasing pressure and laser intensity shows evidence of the presence of clusters in Xe with an increased efficiency compared with He, whereas Ar is an intermediate case for which clusters will start to dominate above a certain backing pressure. Spectral investigations give evidence for tunable harmonic generation in a broad spectral range. A spectral shift of opposite signature caused by the free electrons in the focal volume and the nanoplasmas inside the cluster was observed.

关键词： clusters high harmonic generation nanoplasmas ultrashort pulses

Applying ArcGIS to Estimate the Rates of Shoreline and Back-Shore Area Changes along the Nile Delta Coast, Egypt

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International Journal of Geosciences 2017年第3期8卷 332-348页

作者： Essam A. m. Deabes Coastal Research Institute Alexandria Egypt

This study was undertaken to apply Geographic Information System “GIS” (ArcGIS 9.3) for calculating shoreline change rates and back-shore surface area due to these changes, particularly after constructing marine structures: including seawall, detached breakwaters and groins. modelbuilder in ArcGIS software was used to design and develop an automated technique, module, for estimating such changes (rate and area). These changes are deduced from analysis of beach-nearshore profile surveys between 1970 and 2010 and shoreline position versus prevailing coastal processes. The results show that the major erosion occurred along the Delta promontories;the shoreline of Rosetta retreated (1.6 km) at an average rate of 60 m/yr with loss of back-shore area 6.4 km2;the coastline of Burullus bulge recessed at mean rate of 6 m/yr and decreasing in beach area of 1.31 km2;and at Damietta (Ras El-bar. the shoreline moved backward (6 m/yr) with disappeared in beach area of 1.13 km2. The shape and orientation of these promontories contributed to create alternation between wave convergence zone that eventually causes erosion, and divergence zones that experienced shoreline accretion. Finally, the engineering structures didn’t solve or stop the erosion problem but shifted it from one place to another.

关键词： Nile Delta Coast Shoreline Change Rate Erosion Accretion marine Structures and Geographic Information System (GIS)

杭州湾跨海大桥混凝土结构耐久性原位监测预警系统

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中国公路学报 2010年第2期23卷 30-35页

作者：干伟忠 RAUPACH m 金伟良吕忠达浙江大学结构工程研究所浙江杭州310027 宁波工程学院混凝土结构耐久性研究所浙江宁波315016 亚琛工业大学土木工程研究所北莱茵威斯特法伦亚琛52062 杭州湾大桥工程指挥部浙江宁波315327

为了确保杭州湾跨海大桥混凝土结构达到百年设计使用寿命,评价混凝土结构耐久性状况的动态发展,通过对预埋式钢筋腐蚀无损监测传感系统的国际合作研究,确定了基于电化学原理和辅助光纤技术的耐久性监测技术思路,制定了该工程耐久性动态... 详细信息

为了确保杭州湾跨海大桥混凝土结构达到百年设计使用寿命,评价混凝土结构耐久性状况的动态发展,通过对预埋式钢筋腐蚀无损监测传感系统的国际合作研究,确定了基于电化学原理和辅助光纤技术的耐久性监测技术思路,制定了该工程耐久性动态预报监测平台的构架技术方案,捕获了结构各部位腐蚀预警的个性化判据,优化了全桥测点的布置,集成、改良并安装了控制关键部位的全套系统(共计48套监测单元)。工程实测结果表明:测试数据稳定,并且与实验室研究数据吻合。

关键词：桥梁工程混凝土结构电化学原理耐久性预警系统无损监测