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The Effect of Variable Stator on Performance of a Highly Loaded Tandem Axial Flow Compressor Stage

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Journal of Thermal Science 2016年第3期25卷 223-230页

作者： Hamzeh Eshraghi masoud Boroomand Abolghasem m.Tousi mohammad Toude Fallah Ali mohammadi department of Aerospace Engineering and Centre of excellence on computational aerospace engineering Amirkabir University of Technology Nanotechnology Research and Application Center Sabanci University

Increasing the aerodynamic load on compressor blades helps to obtain a higher pressure ratio in lower rotational speeds. Considering the high aerodynamic load effects and structural concerns in the design process, it is possible to obtain higher pressure ratios compared to conventional compressors. However, it must be noted that imposing higher aerodynamic loads results in higher loss coemcients and deteriorates the overall performance. To avoid the loss increase, the boundary layer quality must be studied carefully over the blade suction surface. Employment of advanced shaped airfoils （like CdAs）, slotted blades or other boundary layer control methods has helped the de- signers to use higher aerodynamic loads on compressor blades. Tandem cascade is a passive boundary layer control method, which is based on using the flow momentum to control the boundary layer on the suction surface and also to avoid the probable separation caused by higher aerodynamic loads. In fact, the front pressure side flow momentum helps to compensate the positive pressure gradient over the aft blade＇s suction side. Also, in compari- son to the single blade stators, tandem variable stators have more degrees of freedom, and this issue increases the possibility of finding enhanced conditions in the compressor off-design performance. In the current study, a 3d design procedure for an axial flow tandem compressor stage has been applied to design a highly loaded stage. Following, this design is numerically investigated using a CFd code and the stage characteristic map is reported. Also, the effect of various stator stagger angles on the compressor performance and especially on the compressor surge margin has been discussed. To validate the CFd method, another known compressor stage is presented and its performance is numerically investigated and the results are compared with available experimental results.

关键词： Compressor Stage Highly Loaded Performance Characteristic Tandem Variable Stator

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Book reviews

Fungal diversity 2014年第6期69卷 147-170页

作者： Samantha C.Karunarathna melvina d’souza Anupama deranagama Leela maya Rizal Paul G.mungai Jingzu Sun K.W.Thilini Chethana Ishani d.Goonasekara Asha Janadaree dissanayake W.m.d.N.Wanasinghe Kasun m.Thambugala dimuthu S.manamgoda Huili Li Komsit Wisitrassameewong Saowaluck Tibpromma Rekhani H.Perera Sylas Lau Kevin d.Hyde mae Fah Luang University 333 Moo 1ThasudMuangChiang Rai 57100Thailand

Fungi,as all other organisms need energy for their development and metabolic *** are very sensitive to and competitive for environmental *** assess their surroundings,both below and above ground and estimate how much energy they need for particular tasks,then realize the optimum *** have the ability to control certain environmental *** perceive themselves and can distinguish between other *** process and evaluate information from surroundings and then modify their behavior accordingly.

关键词： processes. organisms. competitive

Substrate Strengthening of CVd Coated Steels

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材料热处理学报 2004年第5B期25卷 791-795页

作者： O. Kessler m. Heidkamp F. Hoffmann P. mayr Stiftung Institutfiir Werkstofftechnik Bremen GermanyStiftung Institutfiir Werkstofftechnik Bremen GermanyStiftung Institutfiir Werkstofftechnik Bremen GermanyStiftung Institutfiir Werkstofftechnik Bremen Germany

Properties of components and tools can be improved by the combination of coating and heat treatment processes due to the addition of single process advantages and due to the utilization of process interactions. Several low and high alloyed, structural and tool steels (AISI 4140, 52100, H13, A2, d2, etc.) have been treated by CVd-TiN-coating plus laser beam hardening respectively carburizing plus CVd-TiN-coating. Homogeneous, dense TiN-coatings with high hardness, high compressive residual stresses and good adhesion were supported by high strength substrate surfaces. Especially CVd plus laser beam hardening offers the possibility to reduce distortion due to the small heated surface volume.

关键词： CVd 衬底加强镀层钢板激光束强化渗碳

Characterization of optical transitions of Eu^(3+) in lanthanum oxychloride nanophosphor

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Journal of Rare Earths 2011年第4期29卷 345-348页

作者： A. Choubey S. Som m. Biswas S.K. Sharma department of Applied Physics Indian School of Mines Dhanbad 826004 India

This paper presented the studies on the optical properties and calculation of spectral parameters of europium doped lanthanum oxychloride nanophosphor for their possible applications in optoelectronic devices. The compound was doped with 0.1 mol% Eu3＋ ions. The X-ray diffraction study of prepared sample suggested the tetragonal structure with particle size in the range of 18–21 nm. The photoluminescence （PL） emission spectra showed the bright emission in orange-red region from 580 to 630 nm. The most intense emission peak at 621 nm was due to transition 5d0→7F2 in energy levels of Eu3＋ ions. The spectral parameters were calculated from the absorption and emission spectra using Judd-Ofelt intensity parameters. The calculated values of the oscillator strength corresponding to the three transitions 7F1→5d1, 7F1→5d2 and 7F0→5d2 observed at 535, 472 and 465 nm in absorption spectra were 0.30×10–6, 1.36×10–6 and 0.63×10–6, respectively. The value of transi- tion probability （A）, stimulated emission cross-section （） and radiative lifetime （τrad） corresponding to 621 nm emission peak （transition 5d0→7F2） were 308 s–1, 1.22×10–21 cm2 and 3.24×10–3 s, respectively.

关键词： X-ray diffraction optical absorption photoluminescence spectral parameters rare earths

Quantum Steganography via Greenberger-Horne-Zeilinger GHZ_4 State

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Communications in Theoretical Physics 2012年第4期57卷 577-582页

作者： A.El Allati m.B.Ould medeni Y.Hassouni Facultédes Sciences Département de PhysiqueLPT-URAC-13UniversitéMohammed V-Agdal.Av.Ibn BattoutaB.P.1014RabatMaroc The Abdus Salam International Centre for Theoretical Physics TriesteItaly Facultédes Sciences Laboratory of Mathematic Informatics and ApplicationsUniversitéMohammed V-Agdal.Av.Ibn BattoutaB.P.1014RabatMaroc

A quantum steganography communication scheme via Greenberger-Horne-Zeilinger GHZ 4 state is constructed to investigate the possibility of remotely transferred hidden ***,the multipartite entangled states are become a hectic topic due to its important applications and deep effects on aspects of quantum ***,the scheme consists of sharing the correlation of four particle GHZ4 states between the legitimate *** insuring the security of the quantum channel,they begin to hide the secret information in the cover of *** the scheme with the previous quantum steganographies,capacity and imperceptibility of hidden message are *** security of the present scheme against many attacks is also discussed.

关键词： quantum steganography GHZ4 entangled state quantum cryptography quantum communication

mediterranean Berries as Inhibitors of Lipid Oxidation in Porcine Burger Patties Subjected to Cooking and Chilled Storage

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Journal of Integrative Agriculture 2013年第11期12卷 1982-1992页

作者： Rui Ganho mario Estévez mónica Armenteros david morcuende Food Science department ESTMPolytechnic Institute of Leiria Animal Production and Food Science University of ExtremaduraAv.de la Universidad s/n Animal Production and Food Science University of ExtremaduraAv.de la Universidad s/nCáceres 10003Spain

The efifciency of extracts from Arbutus unedo L. （AU）, Crataegus monogyna L. （Cm）, Rosa canina L. （RC）, and Rubus ulmifolius Schott. （RU） to inhibit lipid oxidation in raw, cooked and cooked and chilled （2°C/12 d） porcine burger patties, was investigated. The modiifcation of the fatty acid proifle during processing treatments （cooking and chilling）, the quantitative measurements of thiobarbituric acid reactive substances （TBA-RS）, and lipid-derived volatiles, were used as indicators of lipid oxidation. Polyunsaturated fatty acids （PUFA） gradually decreased during cooking and the subsequent storage of cooked burger patties with this decrease being signiifcantly greater （P〈0.05） in control patties than in those with added berry extracts. In accordance, the control patties showed signiifcantly higher TBA-RS numbers and counts of lipid-derived volatiles in all treatments when compared to the berry-added counterparts （P〈0.05）. Results from the present work show, for the ifrst time, that extracts from A. unedo, C. monogyna, R. canina, and R. ulmifolius are promising antioxidants which could enhance the nutritional, safety and sensory properties of porcine burger patties.

关键词： berries lipid oxidation meat pattiesm TBA-RSm polyunsaturated fatty acids lipid-derived volatiles

Changes in various metabolic parameters in blood and milk during experimental Escherichia coli mastitis for primiparous Holstein dairy cows during early lactation

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Journal of Animal Science and Biotechnology 2015年第1期6卷 37-46页

作者： Kasey m moyes Torben Larsen Peter S?rensen Klaus L Ingvartsen department of Animal and Avian Sciences University of Maryland142 Animal Sciences BuildingMD 20742-231120910 College ParkMDUSA department of Animal Science Faculty of Science and TechnologyAarhus University

Background： The objective of this study was to characterize the changes in various metabolic parameters in blood and milk during ImI challenge with Escherichia coli （E. coh. for dairy cows during early lactation. Thirty, healthy primiparous Holstein cows were infused （h = 0） with -20-40 cfu of live E. coil into one front mammary quarter at -4-6 wk in lactation. daily feed intake and milk yield were recorded. At -12, 0, 3, 6, 12, 18, 24, 36, 48, 60, 72, 96, 108, 120, 132, 144, 156, 168, 180 and 192 h relative to challenge rectal temperatures were recorded and quarter foremilk was collected for analysis of shedding of E. coil Composite milk samples were collected at -180, -132, -84, -36, -12, 12, 24, 36, 48, 60, 72, 84, 96, 132 and 180 h relative to challenge （h=0） and analyzed for lactate dehydrogenase （LdH）, somatic cell count, fat, protein, lactose, citrate, beta-hydroxybutyrate （BHBA）, free glucose （fglu）, and glucose-6-phosphate （G6P）. Blood was collected at -12, 0, 3, 6, 12, 18, 24, 36, 60, 72, 84, 132 and 180 h relative to challenge and analyzed for plasma non-esterified fatty acids （NEFA）, BHBA and glucose concentration. A generalized linear mixed model was used to determine the effect of ImI challenge on metabolic responses of cows during early lactation. Results： By 12 h, E. coli was recovered from challenged quarters and shedding continued through 72 h. Rectal temperature peaked by 12 h post-challenge and returned to pre-challenge values by 36 h post-ImI challenge. daily feed intake and milk yield decreased （P 〈0.05） by 1 and 2 d, respectively, after mastitis challenge. Plasma BHBA decreased （12 h, P 〈0.05） from 0.96± 1.1 at 0 h to 0.57±0.64 mmol/L by ]8 h whereas concentration of plasma NEFA （78 h） and glucose （24 h） were significantly greater, 11 and 27%, respectively, after challenge. In milk fglu, lactose, citrate, fat and protein yield were lower whereas yield of BHBA and G6P were higher after challenge when compared to pre-challenge values. Conclusion

关键词： Cow Early lactation Escherichia coli metabolism

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根据南加州的背景地震活动性估计地震危险性

世界地震译丛 2008年第3期39卷 1-11页

作者： m.d.Petersen m.S.Reichle 张力方中国地震局地壳应力研究所

通过分析南加州的历史地震活动性,找到了一种用6.5级或小于6.5级的背景地震活动性计算地震危险性的合理方法。该方法的基本假设是:未来地震在空间上将群集在4级或4级以上历史主震震中附近。通过分析加州去群集的地震目录,计算每个网格... 详细信息

通过分析南加州的历史地震活动性,找到了一种用6.5级或小于6.5级的背景地震活动性计算地震危险性的合理方法。该方法的基本假设是:未来地震在空间上将群集在4级或4级以上历史主震震中附近。通过分析加州去群集的地震目录,计算每个网格内的地震发生率,并对该发生率进行空间光滑处理,以预测未来地震的空间分布。为了寻找合适的空间光滑函数,我们研究了南加州地震震级与距离(r)的相关性,发现其遵循1/rμ幂次率关系,其中μ随着震级增大而增大。我们的研究结果表明,较大的地震在空间上比较小地震更群集。假设地震活动性遵从古登堡-里克特震级分布关系,我们计算了50年超越概率10%的地面峰值加速度。南加州大部分地区的峰值地面加速度值在0.25g至0.35g(g=10m/s2)之间。所得地震动水平一般比用全部震源模型(包括地质和大地测量资料)所得结果的一半还要小。我们还用蒙特卡罗方法计算了危险性图的总体不确定性,发现该地区大多数区域的变化系数为0.24±0.01。

关键词：地震危险性不确定性光滑函数背景地震活动地震动地震活动性小地震南加州危险性区划震级上限

Local Embeddings of Some Families of Subgroups of Finite Groups

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Acta mathematica Sinica,English Series 2009年第6期25卷 869-882页

作者： A.BALLESTER-BOLINCHES Luis m.EZQUERRO Alexander N.SKIBA departament d'lgebra Universitat de València departamento department of mathematics Gomel State University F.Skorina

In this paper we study the influence of the partial cover and avoidance property on the subgroups of some relevant families of subgroups in a finite group.

关键词： Finite group cover-avoidance property p-supersoluble groups saturated formation