检索结果-南通市图书馆

Experim.ntal investigation of flow and distortion m.tigation by m.chanical vortex generators in a coupled serpentine inlet-turbofan engine system

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2020年第5期33卷 1375-1391页

作者： Im.n m.GHSOUDI m.ham.ad Ali VAZIRY m.stafa mahmoodi Departm.nt of Aerospace Malek-Ashtar University of TechnologyTehran 158751774Iran Departm.nt of Aerospace Malek-Ashtar University of TechnologyIsfahanShahinshahr 115/83145Iran

The perform.nce of com.act,aggressive ducts in advanced propulsion system. is lim.ted by the internal flow separation coupled with the form.tion of secondary counter-rotating vortices that give rise to intensive flow distortions at the duct *** experim.ntal investigation was conducted to study the flow field and passive suppression of flow separation and Aerodynam.c Interface Plane (AIP) distortion in a serpentine air inlet *** were perform.d by a turbofan engine at several Engine Operating Points (EOPs) from.56%(idle) to 100%(m.x).A large total pressure deficit region arose at the upper part of the AIP,which was associated with the upper surface flow *** the new m.chanical S-type vortex generators in two longitudinal positions (VGl and VG2),separation and loss were dim.nished at the upper part of the duct and *** VG2 arrangem.nt attained the m.xim.m.reductions in distortion coefficients which were 73.72%,60.7% and 37.8% in DC(90°),DC(60°) and△P_C/P m.trics,*** the next step of the study,som. unsteady aspects of the flow field were analyzed inside the *** separation onset and reattachm.nt points were determ.ned by the standard deviation of static pressure on the upper *** AIP spectral distribution showed that the boundary of low pressure and high pressure recovery regions was dom.nated by the m.xim.m.***,the PSD diagram.of several probes at AIP revealed the vortex shedding frequency and its higher harm.nics at separation *** energy content of distinct unsteady spectral features in the bare configuration was significantly reduced using VGs,which showed the im.rovem.nt of flow at the duct exit.

关键词： Distortion coefficient Power spectral density Serpentine inlet Total pressure Vortex generators

Stereological study of the effects of vitam.n E on testis structure in rats treated with para-nonylphenol

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2009年第4期11卷 508-516页

作者： m.Soleim.ni m.hranjani A Noorafshan HR m.m.ni m. Abnosi m.mahmoodi m.Anvari Sm.Hoseini Biology Departm.nt Arak University Arak 38156 Iran Anatom. Departm.nt Shiraz University of Medical Sciences Shiraz 71348 Iran Anatom. Departm.nt Research and Clinical Center for Infertility Shahid Sadoughi University of Medical Sciences Yazd 89195-999 Iran

This study was organized to see whether vitam.n E, as a strong antioxidant, could affect the abnorm.lities of testis structure caused by para-nonylphenol （p-NP） during its developm.nt. A total of 32 fem.le Wistar rats after m.ting were divided into four groups （n = 8）： control, vitam.n E （100 m. kg^-1 per day）, p-NP （250 m. kg^-1 per day） and p-NP ＋ vitam.n E. The rats were treated from.the seventh day of pregnancy till the twenty-first day. After weaning, the m.le pups were divided into the sam. groups and were treated orally for 90 days. Finally, the right testis was fixed, processed, stained and studied using stereological m.thods. The weight and volum. of testis, volum. of sem.niferous tubules and its diam.ter, thickness of the basem.nt m.m.rane, height of the germ.nal epithelium. total num.er of types A and B sperm.togonia, sperm.tocyte, sperm.tid and Sertoli cells were significantly reduced in p-NP group when com.ared with other groups. Co-adm.nistration of vitam.n E and p-NP com.ensated for the adverse effects of p-NP on the above param.ters. In addition, treatm.nt with only vitam.n E caused a significant increase in diam.ter, basem.nt m.m.rane thickness and height of germ.nal epithelium. num.er of sperm.togonia and sperm.tocytes. Co-adm.nistration of vitam.n E with p-NP could prevent the adverse effects ofp-NP on the testis structure during its developm.nt.

关键词： developm.nt para-nonylphenol stereology testis vitam.n E

Sim.lation of autom.bile fuel consum.tion and em.ssions for various driver's m.nual shifting habits

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Central South University 2014年第3期21卷 1058-1066页

作者： B.m.shadi Y.Am.ri-rad A.Afkar m.mahmoodi-kaleybar School of Autom.tive Engineering Iran University of Science & Technology Departm.nt of m.chanical Engineering Parand Branch Islamic Azad University

The effects of different habits of the drivers on gear shifting strategies for m.nual powertrain were investigated. For the realization of sim.lation, the shifting habits of the drivers were conducted in the Advisor software to investigate and com.are the em.ssion rates. Sim.lation was developed based on the optim.l gear shifting strategy and criteria and was validated both in fuel econom. and em.ssions by analyzing the results in the various driving cycle and driving styles. To explore an optim.l gear shifting strategy with best fuel econom. and lowest em.ssion for a m.nual transm.ssion, a strategy was designed with a highest possible gear criterion as long as the torque requirem.nt can be satisfied. Based on two different criteria, nam.ly the engine working conditions and the driver's intention, the governing param.ters in decision m.king for gear shifting of m.nual transm.ssion in conventional engine were discussed. It is also shown that the optim.m.gear shifting strategy is based on that both the engine state and the driver's intention elim.nates unnecessary shiftings that are present when the intention is overlooked. The optim.m.shifting habit and the best driving cycle in term. of m.nim.m.em.ssions and fuel consum.tion were proposed.

关键词： gear shifting strategies driving cycle driver m.del Advisor

Chem.selective synthesis of δ-lactones via benzyl radical cyclization utilizing K_2S_2O_8-CuCl_2

在线全文

学校读者我要写书评

暂无评论

Chinese Chem.cal Letters 2008年第12期19卷 1431-1434页

作者： N.O.mahmoodi K.Tabatabaeian m.Kosari S.Zarrabi Departm.nt of Chem.stry Faculty of ScienceUniversity of GuilanRashtP.O.Box 1914Iran

Direct chem.selective oxidation of δ-lactones via highly stable benzyl radical cyclization is reported. The one-pot conversion of prem.de substituted 5-aryl pentanoic acid and 8-benzyl-1-naphthoic acid in the presence of K2S2Os--CuCl2 results to the δ-lactones in m.derate to good yields. The advantages of this m.thodology is using water as a solvent and utilizing available starting m.terials.

关键词： δ-Lactones Benzyl radical Chem.selective oxidation K2S2O8-CuCl2

Integrating water use system. and soil and water conservation m.asures into a hydrological m.del of an Iranian Wadi system

在线全文

学校读者我要写书评

暂无评论

Journal of Arid Land 2020年第4期12卷 545-560页

作者： Narim.n mahmoodi Jens KIESEL Paul D WAGNER Nicola FOHRER Departm.nt of Hydrology and Water Resources m.nagem.nt Institute for Natural Resource ConservationKiel UniversityKiel 24118Germany Departm.nt of Ecosystem.Research Leibniz-Institute of Freshwater Ecology and Inland Fisheries(IGB)Berlin 12489Germany

Water resources are precious in arid and sem.-arid areas such as the Wadis of Iran. To sustainably m.nage these lim.ted water resources, the residents of the Iranian Wadis have been traditionally using several water use system.(WUSs) which affect natural hydrological processes. In this study, WUSs and soil and water conservation m.asures(SWCm.) were integrated in a hydrological m.del of the Halilrood Basin in Iran. The Soil and Water Assessm.nt Tool(SWAT) m.del was used to sim.late the hydrological processes between 1993 and 2009 at daily tim. scale. To assess the im.ortance of WUSs and SWCm., we com.ared a m.del setup without WUSs and SWCm.(Default m.del) with a m.del setup with WUSs and SWCm.(WUS-SWCm.m.del). When com.ared to the observed daily stream.flow, the num.er of acceptable calibration runs as defined by the perform.nce thresholds(Nash-Sutcliffe efficiency(NSE)≥0.68, –25%≤percent bias(PBIAS)≤25% and ratio of standard deviation(RSR)≤0.56) is 177 for the Default m.del and 1945 for the WUS-SWCm.m.del. Also, the average Kling–Gupta efficiency(KGE) of acceptable calibration runs for the WUS-SWCm.m.del is higher in both calibration and validation periods. When WUSs and SWCm. are im.lem.nted, surface runoff(between 30% and 99%) and water yield(between 0 and 18%) decreased in all sub-basins. m.reover, SWCm. lead to a higher contribution of groundwater flow to the channel and com.ensate for the extracted water by WUSs from.the shallow aquifer. In sum.ary, im.lem.nting WUSs and SWCm. in the SWAT m.del enhances m.del plausibility significantly.

关键词： SWAT m.del stream.flow Wadis m.lti-m.tric fram.work water use system. soil and water conservation m.asures Halilrood Basin

CFD-DEm.sim.lation of a pseudo-two-dim.nsional spouted bed com.rising coarse particles

在线全文

学校读者我要写书评

暂无评论

Particuology 2019年第2期17卷 171-180页

作者： B. mahmoodi S.H. Hosseini G. Ahm.di llam.Gas Treating Com.any llam Iran Departm.nt of Chem.cal Engineering llam University llam 69315-516 Iran Departm.nt of m.chanical and Aeronautical Engineering Clarkson University Potsdam NY 13699-5725 USA

In the present study, com.utational fluid dynam.cs (CFD) and the discrete elem.nt m.thod (DEm. are used in conjunction with the Eulerian-Lagrangian m.thod to sim.late a pseudo-two-dim.nsional spouted bed com.rising coarse 6-m. particles. The open-source OpenFOAm.code is used to solve the governing equations. The predicted vertical particle velocity along the bed axis, particle velocity profiles in the radial directi on, power spectral den sity, tim.-averaged particle velocity vectors, bed pressure drop, and solid flow pattern are evaluated and com.ared with existing experim.ntal data. Good agreem.nt is found between the CFD-DEm.results and the m.asured data. It is also shown that the present CFD-DEm.m.del accurately predicts the particle flow pattern throughout the bed. It is found that the drag force, solid stresses, and gravity play im.ortant roles in the CFD-DEm.sim.lation of a spouted bed com.rising coarse particles.

关键词： CFD-DEm Pseudo-2D spouted bed Hydrodynam.cs Coarse particles

Baeyer-Villiger oxidation of cyclic ketones utilizing potassium.peroxydisulfate(K_2S_2O_8) or sodium.perborate(NaBO_3) in acidic m.dia

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chem.cal Letters 2009年第12期20卷 1400-1404页

作者： S.Zarrabi N.O.mahmoodi K.Tabatabaeian m.A.Zanjanchi Departm.nt of Chem.stry Faculty of ScienceUniversity of GuilanRashtP.O.Box 1914Iran

The efficient, green, facile, m.ld and straightforward conversion procedure for the oxidation of cyclic ketones to lactones at room.tem.erature utilizing potassium.peroxydisulfate （K2S2O8） in acidic m.dia is satisfactory to high yields without using traditional chlorinated solvents is reported. This oxidative reagent is cheap and friendly environm.ntal procedure for industrial purposes than use of organic peracids.

关键词： Baeyer-Villiger oxidation Cyclic ketones Potassium.peroxydisulfate (K2S208) Acidic m.dia Sodium.perborate (NaBO3)

An efficient chem.-and regioselective three-com.onent synthesis of pyridazinones and phthalazinones using activated KSF

在线全文

学校读者我要写书评

暂无评论

Chinese Chem.cal Letters 2010年第5期21卷 538-541页

作者： L.Zare N.O.mahmoodi A.Yahyazadeh m.m.m.ghani K.Tabatabaeian Departm.nt of Chem.stry Faculty of SciencesUniversity of GuilanRast 41335-1914Iran

The first three-com.onent and regioselective synthesis of pyridazinones and phthalazinones from.arenes,anhydrides and ArNHNH;in the presence of efficient recyclable heterogeneous catalyst,m.ntm.rillonite-KSF,in high y... 详细信息

关键词： Regioselective Pyridazinones Phthalazinones m.ntm.rillonite-KSF

Spatial variability of soil developm.nt indices and their com.atibility with soil taxonom.c classes in a hilly landscape: a case study at Bandar village, Northern Iran

在线全文

学校读者我要写书评

暂无评论

山地科学学报（英文） 2016年第10期13卷 1746-1759页

作者： m.ryam.OSAT Ahm.d HEIDARI m.stafa KARIm.AN EGHBAL Shahla mahmoodi Soil Science Departm.nt Agriculture and Natural Resources College University Of Tehran Soil Science Departm.nt College of Agriculture Tarbiat Modares University

Soil com.lexity and its m.ltivariable nature restrict the precision of soil m.ps that are essential tools for soil sustainable m.nagem.nt. m.st m.thods developed for reducing im.urities of soil m.p units focus on soil external properties. Taking into account the soil internal properties like geochem.cal weathering indices could increase the m.p unit's purity. However, the com.atibility of these indices with Soil Taxonom.c Classes has not been studied yet. This study has been perform.d in a hilly region with different soil types, vegetation and diverse topographic attributes to illustrate the spatial variability of soil weathering indices and their com.atibility with Soil Taxonom.c Classes. The grid sam.ling is at 100 m.interval. Physico-chem.cal and total elem.ntal analyses were perform.d on 184 and 56 soil sam.les respectively. Eight topographic attributes and 14 com.on soil developm.nt indices were determ.ned. Principal com.onents analysis(PCA) was done to identify the m.st im.ortant com.onents. The results indicated that m.rphological Index(m.) was the best index to show the degree ofsoil developm.nt in the studied region. Spatial distribution of Soil Taxonom.c Classes showed relatively good com.atibility with the first principal com.onent(PC1), Vogt(V) and m.rphological indices. This study showed that using soil developm.nt indices with the conventional m.thods could be helpful tools in soil survey investigations.

关键词： Soil form.tion Spatial variability Weathering Topographic attributes