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跨声轴流压气机转子尾迹的总压平均方法

航空动力学报 2013年第12期28卷 2813-2820页

作者：王偲臣林峰 scott c.morris Joshua cameron 聂超群中国科学院大学物理学院北京100049 中国科学院工程热物理研究所北京100190 中国科学院先进能源动力重点实验室北京100190 Department of Aerospace and Mechanical Engineering University of Notre Dame Notre Dame 46556 USA

对一台跨声轴流压气机转子的尾迹流场进行了数值模拟研究和总压实验测量,结合理论分析方法,研究了面积平均和质量平均这两种常用的总压平均方法在跨声轴流压气机转子尾迹测量中的联系与差异.结果表明:在靠近转子尾缘的测量截面,由于转... 详细信息

对一台跨声轴流压气机转子的尾迹流场进行了数值模拟研究和总压实验测量,结合理论分析方法,研究了面积平均和质量平均这两种常用的总压平均方法在跨声轴流压气机转子尾迹测量中的联系与差异.结果表明:在靠近转子尾缘的测量截面,由于转子尾迹流场中存在总压高而轴向速度低的区域,导致面积平均总压大于质量平均总压;而随着尾迹与主流在下游逐渐掺混均匀,面积平均总压又小于质量平均总压.两种总压平均方法的这一规律性关联可以在研究压气机转子尾迹特征尤其是进行数值计算和实验测量结果对比分析时提供一些有价值的参考.

关键词：跨声压气机转子尾迹总压测量质量平均面积平均

Microbiologically influenced corrosion of cable bolts in underground coal mines:The effect of Acidithiobacillus ferrooxidans

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International Journal of Mining Science and Technology 2021年第3期31卷 357-363页

作者： H.chen O.Kimyon H.Lamei Ramandi M.Manefield A.H.Kaksonen c.morris A.crosky S.Saydam School of Materials Science and Engineering UNSW SydneyNSW 2052Australia School of chemical Engineering UNSW SydneyNSW 2052Australia School of Minerals and Energy Resources Engineering UNSW SydneyNSW 2052Australia cSIRO Land and Water FloreatWA 6014Australia

Reports on corrosion failure of cable bolts,used in mining and civil industries,have been increasing in the past two *** previous studies found that pitting corrosion on the surface of a cable bolt can initiate premature failure of the *** this study,the role of Acidithiobacillus ferrooxidans(***)bacterium in the occurrence of pitting corrosion in cable bolts was *** coupons,made from the wires of cable bolts,were immersed in testing bottles containing groundwater collected from an underground coal mine and a mixture of *** and *** was observed that *** caused pitting corrosion on the surface of cable bolts in the near-neutral *** presence of geomaterials slightly affected the p H of the environment;however,it did not have any significant influence on the corrosion activity of *** study suggests that the common bacterium *** found in many underground environments can be a threat to cable bolts'integrity by creating initiation points for other catastrophic failures such as stress corrosion cracking.

关键词： cable bolt failure Microbiologically influenced corrosion Acidithiobacillus ferrooxidans

Primary metabolism:It’s more than what's for dinner

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Molecular Plant 2021年第8期14卷 1219-1220页

作者： Jeffrey c.Anderson scott c.Peck Department of Botany and Plant Pathology Oregon State UniversityCorvallisOR 97331USA Division of Biochemistry Christopher S Bond.Life Sciences CenterInterdisciplinary Plant GroupUniversity of Missouri-ColumbiaColumbiaMO 65211USA

At the risk of oversimplifying,plant–pathogen interactions are a battle for nutrients in the form of primary metabolic *** have *** want ***,amino acids,and organic acids are continuously being exported from source cells to supply both other plant cells and potentially beneficial microorganisms(Kim et al.,2021).Logically,plants attempt to restrict access to pathogens by withholding these nutrients upon infection;and successful pathogens have evolved strategies to restore nutrient availability(Kim et al.,2021).

关键词： simplify restrict continuously

constitutive behavior and processing maps of a new wrought magnesium alloy ZE20 (Mg-2Zn-0.2ce)

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Journal of Magnesium and Alloys 2020年第1期8卷 111-126页

作者： scott c.Sutton Alan A.Luo Department of Materials Science and Engineering The Ohio State UniversityColumbusOH 43210United States Department of Integrated Systems Engineering The Ohio State UniversityColumbusOH 43210United States Mag Specialties Inc. DenverCO 80210USA

ZE20(Mg-2Zn-0.2ce)^2 is a new wrought magnesium alloy with improved extrudability and mechanical properties[1].To understand the constitutive behavior and workability of this new alloy,Gleeble thermomechanical testing has been carried out in this *** flow stress behavior of ZE20 was investigated between 250℃–450℃ and 10^–3 s^–1–1.0 s^–1 in isothermal *** descriptions of the flow stress are provided.A new general approach at application of the extended Ludwik equation is demonstrated and was found to be more accurate than the hyperbolic sine Arrhenius model while having a similar number of model *** maps were developed based on the experimental results and are verified with microstructural investigation.A region of safe processing with non-basal texture and high activity of dynamic recrystallization(DRX)was found between 375℃ and 450℃,from 10^–1 s^–1 to 10^–2.5 s^–1.A region of potentially safe processing with annealing that is associated with shear band nucleation of non-basal grains was identified for temperatures as low as 300℃ and rates as high as 10^–1 s^–1.

关键词： Magnesium alloys Thermomechanical processing constitutive behavior Processing map Deformation mechanisms

安大略省防治杨柳蛀干害虫——杨干象的初步试验

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山西林业科技 1986年第2期 42-44页

作者： Robert c.morris 蔡炳成林业部保护司

据纽约州约1882年首次报道,杨干象(cryptorrhynchus lapathi)是从原产地欧洲传入的一种杨、柳树蛀干害虫。它不仅为害杨柳树,也会侵害桤树和桦树(Baker1972)。一旦干基受害可使幼树生长减弱直至折断,较大的树干由于幼虫多次为害形成许... 详细信息

据纽约州约1882年首次报道,杨干象(cryptorrhynchus lapathi)是从原产地欧洲传入的一种杨、柳树蛀干害虫。它不仅为害杨柳树,也会侵害桤树和桦树(Baker1972)。一旦干基受害可使幼树生长减弱直至折断,较大的树干由于幼虫多次为害形成许多虫道,材质就会受虫道以及虫道木材变色和真菌危害的影响,病原菌可由杨干象的侵入孔侵入到树体内。杨干象在欧洲是杨树的主要害虫,在美国对柳树的危害也极为严重。在欧洲杨干象是很难控制的(Lapietra 和Arru 1973),在北美尚未发现它的天敌。1977年以前,在杂交杨苗圃种植园中的杨干象还未引起人民的重视(Thomas 和 Rose1979和 Beique 1977),但是,当杂交杨种植增加时,作者们认为,杨干象将是一种危害杨树的主要害虫。Vallee(1979)认为,“在魁北克省,杨干象是危害杨、柳树最严重的害虫”。Vallee(1979)和 Beique(1979)把蛀干害虫造成的危害同抑制树木生长的落叶害虫相比较,认为在杂交杨人工林中,监测蛀干害虫更为困难,这需要(经过培训的)观察人员在杂交杨和天然杨树中,扩大调查范围,记录害虫的危害程度及影响。从1882年以来,栖居在柳树和杨树天然林中的杨干象,已扩散到加拿大南部和美国北部,据 Beique(1979)报道,在魁北克省,每年调查2000多个欧洲山杨、香脂杨、大齿杨和伦巴弟杨样本,发现有80种昆虫,其中蛀干害虫杨干象、三种天牛(Saperda spp.)和一种透翅蛾(Aegeria sp.)是危害树木最严重的害虫。据作者调查表明,杨干象主要寄生在安大略省南部的杂交杨、天然香脂杨和柳树上。1977—1978年调查,在杂交杨中杨干象危害程度较轻,但是,1979—1980年在调查树木受害程度时,发现在3年生以上的人工林中虫害很严重。

关键词：杨干象安大略省杂交杨柳树蛀干害虫香脂杨

A Generic Model to Estimate Wheat LAI over Growing Season Regardless of the Soil-Type Background

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Plant Phenomics 2023年第2期5卷 333-352页

作者： Qiaomin chen Bangyou Zheng Karine chenu scott c.chapman School of Agriculture and Food Sciences The University of QueenslandSt LuciaQLDAustralia Agriculture and Food CSIROQueensland Bioscience PrecinctSt LuciaQLDAustralia The University of Queensland Queensland Alliance for Agriculture and Food InnovationToowoombaQLDAustralia

It is valuable to develop a generic model that can accurately estimate the leaf area index(LAI)of wheat from unmanned aerial vehicle-based multispectral data for diverse soil backgrounds without any ground *** achieve this objective,2 strategies were investigated to improve our existing random forest regression(RFR)model,which was trained with simulations from a radiative transfer model(PROSAIL).The 2 strategies consisted of(a)broadening the reflectance domain of soil background to generate training data and(b)finding an appropriate set of indicators(band reflectance and/or vegetation indices)as inputs of the RFR *** RFR models were tested in diverse soils representing varying soil types in *** analysis indicated that adopting both strategies resulted in a generic model that can provide accurate estimation for wheat LAI and is resistant to changes in soil *** validation on 2 years of field trials,this model achieved high prediction accuracy for LAI over the entire crop cycle(LAI up to 7 m^(2)m^(−2))(root mean square error(RMSE):0.23 to 0.89 m^(2)m^(−2)),including for sparse canopy(LAI less than 0.3 m^(2)m^(−2))grown on different soil types(RMSE:0.02 to 0.25 m^(2)m^(−2)).The model reliably captured the seasonal pattern of LAI dynamics for different treatments in terms of genotypes,plant densities,and water–nitrogen managements(correlation coefficient:0.82 to 0.98).With appropriate adaptations,this framework can be adjusted to any type of sensors to estimate various traits for various species(including but not limited to LAI of wheat)in associated disciplines,e.g.,crop breeding,precision agriculture,etc.

关键词： soil Wheat breeding

跨音速转子叶顶泄漏流/主流交界面的前移机制

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工程热物理学报 2011年第6期32卷 929-932页

作者：杜娟林峰陈静宜 Mark H Ross Joshua D cameron scott c.morris 中国科学院工程热物理研究所北京100190 中国科学院先进能源与动力重点实验室北京100190 Hessert Laboratory Department of Mechanical and Aerospace EngineeringUniversity of Notre Dame

采用数值计算和实验研究相结合的方法,研究了跨音速转子叶顶泄漏流与主流交界面轴向位置随流量的变化规律和机制。该跨音转子是美国圣母大学一级半跨音速压气机转子。研究发现机匣壁面脉线分布能够定性反映壁面轴向剪切应力分布,可用来... 详细信息

采用数值计算和实验研究相结合的方法,研究了跨音速转子叶顶泄漏流与主流交界面轴向位置随流量的变化规律和机制。该跨音转子是美国圣母大学一级半跨音速压气机转子。研究发现机匣壁面脉线分布能够定性反映壁面轴向剪切应力分布,可用来识别叶顶泄漏流与主流的交界面位置。通过机匣壁面的脉线分布,可以看出机匣壁面存在两条零剪切应力线。第一条零剪切应力线表示来流与叶顶泄漏流之间交界面的时间和周向平均轴向位置,在小流量工况下交界面靠近顶部叶片的前缘。计算和实验结果都表明,随着质量流量的减小,叶顶泄漏流与主流交界面的轴向位置不断向叶片前缘移动。在近失速点,交界面到达叶片前缘,泄漏流即将溢出。泄漏流与主流的轴向动量比随流量减小不断增大的变化规律进一步说明,间隙区域泄漏流与主流的轴向动量平衡是导致交界面不断前移直至溢出的内在机制。

关键词：叶顶泄漏流/主流交界面轴向剪切应力跨音速压气机转子

Off-site trimer superfluid on a one-dimensional optical lattice

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chinese Physics B 2017年第4期26卷 168-173页

作者：范二女 Tony c scott 张万舟 college of Physics and Optoelectronics Taiyuan University of TechnologyTaiyuan 030024China Near India Pvt Ltd No.71/72Jyoti Nivas College RoadKoramangalaBangalore 560095India

The Bose-Hubbard model with an effective off-site three-body tunneling,characterized by jumps towards one another,between one atom on a site and a pair atoms on the neighborhood site,is studied systematically on a one-dimensional（1D） lattice,by using the density matrix renormalization group *** off-site trimer superfluid,condensing at momentum k = 0,emerges in the softcore Bose-Hubbard model but it disappears in the hardcore Bose-Hubbard *** results numerically verify that the off-site trimer superfluid phase derived in the momentum space from[***.A81,011601（R）（2010）]is stable in the thermodynamic *** off-site trimer superfluid phase,the partially off-site trimer superfluid phase and the Mott insulator phase are found,as well as interesting phase transitions,such as the continuous or first-order phase transition from the trimer superfluid phase to the Mott insulator *** results are helpful in realizing this novel off-site trimer superfluid phase by cold atom experiments.

关键词： Bose-Hubbard model off-site trimer superfluid density matrix renormalization group method

Artificial lights improve the catchability of snow crab (chionoecetes opilio) traps

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Aquaculture and Fisheries 2017年第3期2卷 124-133页

作者： Khanh Q.Nguyen Paul D.Winger corey morris scott M.Grant Fisheries and Marine Institute Memorial University of NewfoundlandSt.John'sNL A1C 5R3Canada Fisheries and Oceans canada St John'sNL A1C 5X1Canada Nha Trang University 2 Nguyen Dinh ChieuNha Trang 57000Viet Nam

This study investigated the behaviour and commercial catchability of snow crab(chionoecetes opilio)in response to different low-powered LED lights under laboratory and field *** created a novel choice-experiment in a laboratory setting in which we investigated the behaviour of snow crab in response to coloured LED *** results showed that snow crab movement was dependent on light colour,with animals choosing to move toward blue and white lights,away from purple lights,and no detectable effect for green and red *** then conducted two field experiments to investigate the effect of the same LED lights on the catch rates of commercial traps during the 2016 snow crab fishery on the east coast of Newfoundland and *** from the first field experiment showed that adding white and purple LED lights into baited traps significantly improved catch Per Unit Effort(cPUE)by 77% and 47% *** from the second field experiment showed that unbaited traps equipped with only LED lights(no bait),could also catch snow crab in comparable amounts to traditional baited traps,with soak time and depth explaining some of the variation in *** together,these experiments suggest that fishing enterprises can improve their catching performance and profitability by adding LED lights to their traps,or by using LED lights as a bait replacement.

关键词： chionoecetes opilio Snow crab LED light catchability crab behaviour