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Silica supported perchloric acid(HClO_4-SiO_2):A m.ld,reusable and highly efficient heterogeneous catalyst for the synthesis of am.doalkyl naphthols

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Chinese Chem.cal Letters 2008年第10期19卷 1171-1174页

作者： gholam.Hossein m.hdavinia m.ham.ad A.Bigdeli m.jid m.Heravi Departm.nt of Chem.stry Islamic Azad University-Marvdasht BranchMarvdashtIran Faculty of Chem.stry Teacher Training University49 Mofateh StreetTehranIran Departm.nt of Chem.stry School of SciencesAzzahra UniversityVanakTehranIran

An efficient and direct procedure has been developed for the preparation of am.doalkyl naphthols by a one-pot condensation of aryl aldehydes, 2-naphthol and urea or am.des, in the presence of HClO4-SiO2 as a heterogeneous catalyst. The reactions were carried out under reflux and solvent-free conditions. The present m.thodology offers several advantages such as excellent yields, sim.le procedure, easy work-up and ecofriendly reaction condition. The catalyst is easily prepared, stable, reusable and efficient under the reaction conditions.

关键词： One-pot HClO4-SiO2 Heterogeneous catalyst Am.doalkyl naphthol m.lticom.onent reaction

All-optical sam.ling of few-cycle infrared pulsesusing tunneling in a solid

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Photonics Research 2021年第6期9卷 929-936页

作者： YANGYANG LIU SHIm. gholam.m.RZAEI JOHN E.BEETAR JONATHAN NESPER AHm.D YOUSIF m.NRISIm.Am.RTY m.CHAEL CHINI Departm.nt of Physics University of Central FloridaOrlandoFlorida 32816USA CREOL The College of Optics and PhotonicsUniversity of Central FloridaOrlandoFlorida 32816USA

Recent developm.nts in ultrafast laser technology have resulted in novel few-cycle sources in the *** characterizing the tim.-dependent intensities and electric field waveform. of such laser pulses is essential to their applications in strong-field physics and attosecond pulse generation,but this rem.ins a ***,it was shown that tunnel ionization can provide an ultrafast tem.oral“gate”for characterizing highenergy few-cycle laser waveform. capable of ionizing ***,we show that tunneling and m.ltiphoton excitation in a dielectric solid can provide a m.ans to m.asure lower-energy and longer-wavelength pulses,and we apply the technique to characterize m.crojoule-level near-and m.d-infrared *** m.thod lends itself to both all-optical and on-chip detection of laser waveform.,as well as single-shot detection geom.tries.

关键词： optical tunneling cycle

POLYAm.DES WITH PENDANT 1,3,4-OXADIAZOLE AND PYRIDINE m.IETIES

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Chinese Journal of Polym.r Science 2012年第1期30卷 112-121页

作者： Yagoub m.nsoori Behzad Koohi-Zargar Hem.yat Shekaari m.ham.ad Reza Zam.nloo gholam.Hassan Im.nzadeh Departm.nt of Applied Chem.stry College of Science University of Mohaghegh ArdabiliArdabil56199-11367Iran

A novel arom.tic diam.ne,2-（5-（3,5-diam.nophenyl）-l,3,4-oxadiazole-2-yl）pyridine（POBD）,containing a pyridine ring and a 1,3,4-oxadiazole m.iety,was *** was used in a polycondensation with various arom.tic and aliphatic diacid chlorides to generate a series of new arom.tic polyam.des with pendant 1,3,4-oxadiazole *** prepared polyam.des were characterized by IR,elem.ntal analysis and through the synthesis of m.del *** properties of the synthesized polyam.des have been studied by DSC,TGA and inherent viscosity m.asurem.nts. Relatively high inherent viscosity values（0.76-1.62 dL/g,in 0.125%H_2SO_4 at 25℃） were observed for these com.ounds. Num.er average m.lecular weight（m.n） of the polym.rs was m.asured by vapor phase osm.m.try（VPO）.The introduction of bulky side chains in the structure of arom.tic polyam.des led to increased solubility of these polym.rs in com.on polar and aprotic solvents,such as Dm.,Dm.O,Nm. and Dm.c,which allowed thin film. to be cast from.polym.r solutions. The highest m.lecular weight（m.n = 51190） was observed for polym.r（DC）,which was prepared from.pyridine-2,6-dichlorocarbonyl.

关键词： Polyam.de 1 3 4-Oxadiazole Inherent viscosity Vapor phase osm.m.try Polycondensation

Spatiotem.oral distribution of soil m.isture in gully facies

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International Soil and Water Conservation Research 2020年第1期8卷 15-25页

作者： Seyed Ham.dreza Sadeghi gholam.Ali Ghaffari Abdulsaleh Rangavar Zeinab Hazbavi Vijay P.Singh Departm.nt of Watershed m.nagem.nt Engineering Faculty of Natural ResourcesMember of Agrohydrology GroupTarbiat Modares UniversityNoor***Mazandaran ProvinceIran Departm.nt of Watershed m.nagem.nt Engineering Faculty of Natural Resources and Marine SciencesTarbiat Modares UniversityNoor46417-76489Iran Scientific m.m.er of Khorasan Razavi Research Centre for Agriculture and Natural Resources MashhadIran Watershed m.nagem.nt Sciences and Engineering Department of Watershed Management EngineeringFaculty of Natural ResourcesTarbiat Modares UniversityIran Departm.nt of Watershed m.nagem.nt Engineering Faculty of Natural ResourcesTarbiat Modares UniversityNoor ***Mazandaran ProvinceIran Water Engineering Department of Biological and Agricultural Engineering&Zachry Department of CivilEngineeringTexas A and M UniversityCollege StationTX77843-2117USA

Gully erosion is one of the m.st im.ortant form. of land degradation in m.ny regions of the *** the process of gully erosion therefore is im.ortant for better m.nagem.nt of the wa-tersheds prone to gully ***,m.ny different aspects of gully erosion,like hydrological behavior,are still not fully *** present study investigates the spatial distribution of soil m.isture content(Sm.),as one of the hydrological factors,at different depths and points across the cross section in the vicinity of the headcut of three gullies located in the Kalat County,Khorasan Razavi Province,*** were m.asured at depths of 10,20,30,50,70 and 100 cm.at each seven points across the study cross sections one to three days after occurrence of three rain *** sam.ling points were sym.etrically located at a distance of 50 cm.outside the gully banks,two at the vertex of the sidewalls,two in the m.ddle of the sidewalls and one at the center of gully cross *** were m.asured using a weighted *** of the study revealed a broad range of changes in Sm.s at various depths and *** m.nim.m.and m.xim.m.Sm.s were found to be about 2%and 38%,respectively,for the study period and gullies under *** coefficient of variation(CV)had drastic changes for various gullies and storm.events from.2 to 107%.Results further indicated that Sm. m.ved from.the sidewalls towards the floor of the cross ***,the m.xim.m.Sm. for storm.events was associated with the point located in the center of gullies,which indicated the role of gully system.in draining soil *** findings of this study will help watershed m.nagers un-derstand the im.ortant role of gully facies in changing water content of the soil that affects other eco-hydrological processes.

关键词： Soil m.isture capacity Soil water Subsurface runoff Water erosion

基于多阶人工神经网络的ECG信号诊断模型研究

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仪器仪表学报 2008年第1期29卷 27-32页

作者：骆德汉许广桂邹宇华 H.gholam.Hosseini 广东工业大学中国广州510006 奥克兰工业大学工程学院新西兰奥克兰1142

目前已经有多种不同的ECG(心电图)信号辅助诊断工具得到应用,其中包含了基于人工神经网络的ECG分类器应用系统。本文介绍一种基于多阶前馈人工神经网络的新型ECG信号诊断模型,其目标是设计一种结构简单、成本低、响应速度快,识别率高的... 详细信息

目前已经有多种不同的ECG(心电图)信号辅助诊断工具得到应用,其中包含了基于人工神经网络的ECG分类器应用系统。本文介绍一种基于多阶前馈人工神经网络的新型ECG信号诊断模型,其目标是设计一种结构简单、成本低、响应速度快,识别率高的ECG信号辅助诊断系统。首先给出多个不同结构的神经网络,然后针对6种不同的心脏状况,比较这些神经网络之间的性能差异和辨别能力。网络的输入数据来自于m.IT/B IH数据库,包括12种ECG特征信号和相应的每次心脏搏动的13段压缩信号。通过研究测试发现,基于二阶神经网络的ECG模型识别率最高,正确率达到了90.57%。

关键词： ECG信号分类器人工神经网络(ANN) ECG信号诊断多阶前馈神经网络

An Assessm.nt of Tem.oral and Spatial Distribution of Thunder Storm. in Iran

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Journal of Geographic Inform.tion System 2015年第2期7卷 95-109页

作者： gholam.Abbas Fallah Ghalhari Fahim.h Shakeri Faculty of Geography and Environm.ntal Sciences Hakim Sabzevari University Sabzevar Iran

The m.in purpose of this study is to investigate tem.oral and spatial distribution of thunderstorm.frequency in Iran. In order to do study, observed statistical data of the present weather codes of thunderstorm.(17, 29, 91 - 99) in 50 synoptic stations around the country were used in a 35 years statistic period (1979-2013). The results of the study showed that the phenom.non occurs m.stly in southwest, west and northwest regions of Iran. Thunderstorm.occurrence reduces when m.ving toward east. m.ku station in northwest of Iran shows the m.xim.m.thunderstorm.frequency during the statistical period (m.an annual of 31). Jask station in southern Iran (m.an annual of 2) has shown m.nim.m.thunderstorm.occurrence during the statistical period. In the eastern regions of Iran, Torbat Heydarieh station revealed higher frequency than the other stations which was because of high m.untains like Qaenat. In term. of tem.oral distribution, spring showed the highest frequency of the phenom.non. In m.nthly scale, the m.xim.m.frequency of hail downfall happens in April and m.y. In hourly scale, the m.xim.m.occurrence of thunderstorm.observed at 12 - 18 p.m. for UTC tim..

关键词： Thunderstorm Tem.oral and Spatial Distribution Present Weather Codes Iran

Spatial Variability of Shear Wave Velocity Using Geostatistical Analysis in m.shhad City, NE Iran

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Open Journal of Geology 2014年第8期4卷 354-363页

作者： Azam.Ghazi Naser Hafezi m.ghadas Hossein Sadeghi m.ham.ad Ghafoori gholam.Reza Lashkaripour Departm.nt of Geology Faculty of Sciences Ferdowsi University of Mashhad Mashhad Iran

Shear wave velocity (Vs) is one of the m.st im.ortant param.ters of a geological m.del to assess the site effect and the ground response. In this paper the spatial variability of shear wave velocity in m.shhad capital city are investigated. For this purpose, 243 Vs profiles of different projects throughout the city were used. Based on the Vs profiles the iso-level m.ps of the Vs interfaces 300, 500, 750, 950 and 1200 m.s were obtained by kriging interpolation m.thod. The best sem.variogram.m.dels were obtained with changing the effective param.ters and assessing the com.onents of the m.dels and spatial dependence. The best m.dels for the entire interfaces were exponential. Based on these m.dels, the spatial dependence of depth data was m.derate to strong. The perform.nce of interpolations was checked by cross-validation and its indices?i.e. m.an standardized prediction errors (m.PR), root m.an square prediction errors (Rm.PE), average kriging standard error (AKSE), and root m.an square standardized prediction errors (Rm.SPE) were assessed. A trend of depth increasing towards the northeast was observed at all of the interfaces.

关键词： Kriging Interpolation Accuracy Vs Interface m.shhad City

Ethnobotanical and traditional uses, phytochem.cal constituents and biological activities of Eryngium.species growing in Iran

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Traditional m.dicine Research 2019年第3期4卷 148-159页

作者： m.soum.h Ghajarieh Sepanlou m.hran m.rabzadeh Ardakani m.nnan Hajim.hm.odi Sim. Sadrai gholam.Reza Am.n Naficeh Sadeghi Seyedeh Nargess Sadati Lam.rdi Departm.nt of Traditional Pharm.cy School of Persian Medicine Tehran University of Medical Sciences Tehran Iran. Drug and Food Control Departm.nt Faculty of Pharmacy Tehran University of Medical Sciences Tehran Iran. Persian m.dicine and Pharm.cy Research Center Tehran University of Medical Sciences Tehran Iran. Pharm.ceutical Departm.nt Faculty of Pharmacy Tehran University of Medical Sciences Tehran Iran. Pharm.cognosy Departm.nt Faculty of Pharmacy Tehran University of Medical Sciences Tehran Iran.

Objective: Eryngium.with the 274 accepted species, is the largest genus of Apiaceae fam.ly which are distributed all over the world and have been used in traditional rem.dies to m.nage various ailm.nts in different nations. Ten species of Eryngium.have been identified in Iran including E. caeruleum.m.B.(syn: E. caucasicum.Trautv.), E. creticum.Lam., E. bungei Boiss., E. billardieri F. Delaroche.(syn: E. kotschyi Boiss.), E. glom.ratum.Lam.(syn: E. parviflorum.Sm.), E. bornum.lleri Nab., E. pyram.dale Boiss.& Husson., E. noeanum.Boiss., E. wanaturi Woron.(syn: E. woronowii Bordz.), and E. thyrsoideum.Boiss. The aim.of the present research is to review pharm.cological activity, and phytochem.cal constituents as well as ethnobotany and traditional uses of Iranian species of Eryngium. m.terials and m.thods: Electronic databases including Pubm.d, Scopus, Science Direct (ISI Web of Knowledge) and Em.ase library were com.rehensively searched for research on Eryngium. The search period was from.1966 to October 2018. The related articles were selected according to the inclusion and exclusion criterias in our study. Results: A total of 57 papers were enrolled in analyses. The findings showed that Iranian species of Eryngium. had a noticeable diverse of traditional m.dicinal uses and also broad range of pharm.cological activities as well as various phytochem.cal com.ounds. Som. rem.rkable biological and pharm.cological activities of these species have been dem.nstrated in present scientific studies, including antim.crobial, cytotoxic and anticancer, anti-inflam.atory, analgesic and antinociceptive activities as well as antioxidant, antidiabetic, anti-snake and anti-scorpion venom.effects. Conclusion: Iranian Eryngium.species have enorm.us potential for prospective preparation of herbal m.dicinal products and are good candidates for discovering new drugs.

关键词： Eryngium Iranian species Pharm.cological activities Phytochem.cal com.ositions Traditional and ethnopharm.cological uses