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Structural and Optical Behavior of Germanium Quantum Dots

Chinese Physics Letters 2012年第11期29卷 202-206页

作者： ALIREZA Samavati Z.Othaman S.K.Ghoshal m.R.Dousti R.J.Amjad Ibn sina Institute for Fundamental Science Studies Universiti Teknologi Malaysia81310 SkudaiJohorMalaysia Advanced Optical material Research Group Department of PhysicsFaculty of ScienceUniversiti Teknologi Malaysia81310 UTM SkudaiJohorMalaysia

Controlled growth,synthesis,and characterization of a high density and large-scale Ge nanostructure by an easy fabrication method are key issues for optoelectronic *** quantum dots(QDs)having a density of~1011 cm^(-2) and a size as small as~8 nm are grown by radio frequency magnetron sputtering on Si(100)substrates under different heat *** annealing temperature dependent structural and optical properties are measured using AFm,XRD,FESEm,EDX,photoluminescence(PL)and Raman *** effect of annealing is found to coarsen the Ge QDs from pyramidal to dome-shaped structures as they grow larger and transform the nanoislands into relatively stable and steady state ***,the annealing allows the intermixing of Si into the Ge QDs and thereby reduces the strain energy that enhances the formation of larger *** room temperature PL spectra exhibits two strong peaks at~2.87 eV and~3.21 eV attributed to the interaction between Ge,GeO_(x) and the possibility of the presence of QDs core-shell *** reports so far exist on the red shift~0.05 eV of the strongest PL peak that results from the effect of quantum ***,the Raman spectra for the pre-annealed QDs that consist of three peaks at around~305.25 cm^(-1),409.19 cm^(-1) and 515.25 cm^(-1) are attributed to Ge-Ge,Ge-Si,and Si-Si vibration modes,*** Ge-Ge optical phonon frequency shift(~3.27 cm^(-1))associated with the annealed samples is assigned to the variation of shape,size distribution,and Ge composition in different *** variation in the annealing dependent surface roughness and the number density is found to be in the range of~0.83 to~2.24 nm and~4.41 to~2.14×10^(11)cm^(-2),respectively.

关键词： spectroscopy annealing annealed

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Fabrication and mechanical properties of mWCNTs-reinforced aluminum composites by hot extrusion

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Rare metals 2012年第4期31卷 372-378页

作者： mortazavi majid majzoobi G.H. Golikand A.Noozad Reihani A. mortazavi S.Z. Gorji m.S. Department of mechanical Engineering Faculty of EngineeringBu-Ali Sina UniversityHamedanIran Department of materials Engineering Monash UniversityClaytonVictoria 3800Australia material Research School Tehran P.O.Box 31485-498Iran School of materials Engineering Najafabad BranchIslamic Azad UniversityIsfahanIran School of materials and mineral Resources Engineering Universiti Sains MalaysiaPenangMalaysia

Over the past decade,the interest in aluminum composites reinforced with carbon nanotubes has grown *** have been carried out to overcome problems with uniform dispersion,interfacial bonding,void formation and carbide formation of the *** the present work,multi-wall carbon nanotubes(mWCNTs) aluminum composites were ***-energy ball milling with the aim at developing well-dispersed mWCNTs Al composites was followed by cold compaction,sintering,and hot extrusion at 500 ℃.Different amounts of stearic acid as processing control agent(PCA) is used in order to minimize cold welding of the Al particles,and to produce finer *** scanning calorimetry(DSC),scanning electron microscopy(SEm),transmission electron microscopy(TEm),and X-ray diffraction(XRD) were employed to analyze the mWCNTs,the aluminum powder,and the composites’ microstructural *** hardness and tensile properties of the composites are also *** results showed 500% increase in yield stress after the addition of 1 wt% mWCNTs in Al-mWCNTs based *** ball-milling time of 4 h is found to be sufficient as excessive milling time destroys a vast number of mWCNTs.

关键词： aluminum matrix composite multi-wall carbon nanotubes(mWCNTs) ball milling mechanical properties

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Effect of equal channel angular extrusion on Al-6063 bending fatigue characteristics

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International Journal of minerals,metallurgy and materials 2015年第4期22卷 395-404页

作者： J.Nemati G.H.majzoobi S.Sulaiman B.T.H.T.Baharudin m.A.Azmah Hanim Department of mechanical and manufacturing Engineering University Putra Malaysia Engineering Faculty Bu-Ali Sina University School of mechanics Islamic Azad UniversityTakestan Branch

The purpose of this investigation was to refine the grains of annealed 6063 aluminum alloy and to improve its yield stress and ul- timate strength. This was accomplished via the equal channel angular extrusion （ECAE） process at a temperature of 200℃ using route A, with a constant ram speed of 30 mm/min through a die angle of 90° between the die channels for as many as 6 passes. The experiments were conducted on an Avery universal testing machine. The results showed that the grain diameter decreased from 45 μm to 2.8 μm after 6 extru- sion passes. The results also indicated that the major improvement in fatigue resistance occurred after the first pass. The subsequent passes improved the fatigue life but at a considerably lower rate. A maximum increase of 1100% in the case of low applied stresses and an ap- proximately 2200% increase in fatigue resistance in the case of high applied stresses were observed after 5 passes. The improvement of fa- tigue resistance is presumed to be due to （1） a reduction in the size and the number of Si crystals with increasing number of ECAE passes, （2） the aggregation of Cu during the ECAE process, （3） the formation and growth of CuA12 grains, and （4） grain refinement of the A1--6063 alloy during the ECAE process.

关键词： aluminum alloys equal channel angular pressing bending fatigue life grain size microstructure

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儿科日间手术中超重（或肥胖症）与胃液特性的关系：在禁食指南和误吸风险评估方面的意义

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麻醉与镇痛 2010年第6期6卷 38-49页

作者： Scott D. Cook-Sather Paul R. Gallagher Lydia E. Kruge Jonathan m. Beus Brian P. Ciampa Kevin Conor Welch sina Shah-Hosseini Jieun S. Choi Reshma Pachikara Kim minger Ronald S. Litman mark S. Schreiner 周洁(译) 李士通(校) Departments of Anesthesiology and Critical Care medicine Departments of Biostatistics and Epidemiology Nursing The Children's Hospital of Philadelphia The University of Pennsylvania School of Medicine Philadelphia Pennsylvania 不详

背景超重或肥胖的日间手术儿科患者手术前2小时禁水的安全性尚未得到证实。健康的儿童和肥胖的成人在手术前禁水2小时后残留胃液量（GFVs）并不多，因此认为误吸风险并不高。因此我们将测算日间手术患者中超重症或肥胖症的患病率，并假... 详细信息

背景超重或肥胖的日间手术儿科患者手术前2小时禁水的安全性尚未得到证实。健康的儿童和肥胖的成人在手术前禁水2小时后残留胃液量（GFVs）并不多，因此认为误吸风险并不高。因此我们将测算日间手术患者中超重症或肥胖症的患病率，并假设不管是体重指数还是禁食时间均不会对GFV或胃液pH值产生显著的影响。所有受试儿童均于手术前禁清水2小时，并假设超重或肥胖患儿的GFV不会多于偏瘦或正常体重患儿，而呕吐或误吸的风险也很低。方法本研究中连续纳入了1000例2－12岁行日间手术的患儿，记录人口统计学资料、病史、身高和体重。另外纳入1000例需全麻插管的日间手术患儿（2。12岁）进行研究。气管插管后，经口插入一根14—18F的胃管，抽空胃内容物。用药情况、禁食时间、GFV、pH值和呕吐事件均被详细记录。采用疾病预防及控制中心的生长图表（2000）评定理想体重（IBW=第50个百分位数），并对患儿进行分层：偏瘦或正常体重（BmI在第25—75个百分位数）、超重（第95个百分位数〈BmI≥第85个百分位数）、肥胖（BmI≥第95个百分位数）。结果在所有的日间手术患儿中有14％属于超重，13．3％属于肥胖。肥胖儿按公斤体重算出的GFV较低（P〈0．001）。当我们用IBW进行校正后，所有BmI组中GFV（mw校正后）的容量都相等（均值为0．96ml／kg，SD为0．71；中位数为0．86ml／kg，IQR为0．96）。手术前使用对乙酰氨基酚和咪达唑仑均导致GFV（1BW校正后）增加（P=0．025和P=0．001）。而ASA11I级（P=0．024）、男性（P=0．012）、胃食管反流性疾病（P=0．049）和使用质子泵抑制剂（P=0．018）患儿的GFV（mw校正后）较低。GFV（IBw校正后）与禁食时间和年龄无关。胃液酸度较低与年龄较小（P=0．005）、BmI较高（P=0．036）和美国非洲裔（P=0．033）患儿等因素相关。有8例患儿在全麻诱导时发生了呕吐（其中50％有肥胖症，P=0．052，75％患有阻塞性睡眠呼吸暂停症，P=0．061）。呕吐与ASA分级较高有关，但却与禁食时间的长短无关。研究中没有出现误吸事件。结论27％的儿科日闻手术患儿属超重或肥胖儿童。无论进食时间长短或BmI如何，GFV（IBw校正后）均为1ml／kg，因此这些患儿均可以在手术前2小时饮清水。在此研究群体中，罕见的呕吐事件与禁食时间的缩短并无相关性。

关键词：禁食时间儿科患者风险评估肥胖症超重症胃液量误吸阻塞性睡眠呼吸暂停症

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The Prevalence of Human Papilloma Virus (HPV) among Egyptian Women and Its Impact: An Observational Study

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Open Journal of Obstetrics and Gynecology 2021年第7期11卷 879-884页

作者： m. Elazab O. Ali m. C. Ramadan m. Hassan H. Aljedaani F. Gardner Al Galaa Teaching Hospital Cairo Egypt North Cumbria University Hospital North Cumbria UK New Cairo General Hospital Cairo Egypt Ibn sina College Hospital for medical Science Jeddah KSA DFFP MRCOG Portsmouth Hospital Portsmouth UK

Cancer is one of the most prevalent causes of mortality worldwide. In the cervix, it is confirmed to be caused by different high-risk human papillomavirus (HPV) types. Although many studies have already been conducted worldwide on the epidemiology of HPV infection and their oncogenic properties, limited data are available on HPV prevalence, incidence andmily:Verdana;"> its impacts in Egypt.

关键词： HPV Screening Test Cancer Cervix

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香格里拉普达措国家公园长苞冷杉种群空间分布格局及关联性

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生态学杂志 2021年第12期40卷 3860-3869页

作者：顾荣张彩彩和正华杨荣陈瑶冯萍斯那取宗赵冬莲益西央初吴俊华林露湘大理大学东喜玛拉雅研究院云南大理671003 香格里拉普达措国家公园管理局云南迪庆674499 中国科学院西双版纳热带植物园热带森林生态学重点实验室昆明650201

植物种群不同发育阶段的空间分布格局及关联性能够反映植物种群的现状和发展趋势,并揭示其背后潜在的生态过程。本研究以云南省香格里拉普达措国家公园亚高山寒温性针叶林1 hm2永久固定监测样地内的优势种长苞冷杉(Abies georgei)为对象... 详细信息

植物种群不同发育阶段的空间分布格局及关联性能够反映植物种群的现状和发展趋势,并揭示其背后潜在的生态过程。本研究以云南省香格里拉普达措国家公园亚高山寒温性针叶林1 hm2永久固定监测样地内的优势种长苞冷杉(Abies georgei)为对象,分析其种群径级结构,并采用RipleyL函数探究其不同发育阶段空间分布格局及相互关联性。结果表明:(1)长苞冷杉的径级结构呈"金字塔"型分布,幼树(1 cm≤DBHm)、中树(5 cm≤DBHm)和成树(DBH≥15 cm)个体数量分别占整个种群数量的47.42%、31.55%和21.03%,种群结构为增长型,更新状态良好;(2)不同发育阶段长苞冷杉的空间分布格局存在差异。以完全空间随机为零模型,幼树和中树分别在0~45、0~35 m的尺度上呈显著的聚集分布;成树在所有尺度上呈随机分布;以异质泊松点过程为零模型去除生境异质性的效应后,幼树、中树和成树基本在所有尺度上呈随机分布,说明生境异质性是导致长苞冷杉种群不同径级空间聚集分布的主要原因;(3)幼树与中树在邻体尺度上呈显著正相关空间关联,幼树与成树、中树与成树均在邻体尺度上呈显著的负相关空间关联,并随着尺度的增大而逐渐减弱,最后呈不相关空间关联。潜在的负密度制约机制驱动长苞冷杉从幼树和中树的聚集分布转为成树的随机分布;长苞冷杉幼树和中树可能受同样的生境过滤影响而呈聚集分布,并导致二者呈现正相关空间关联,而潜在的成树对中树的不对称竞争以及潜在的专一性病原菌和害虫对幼树的攻击可能导致成树与中树、成树与幼树的负相关空间关联。

关键词：空间点格局 RipleyL函数空间关联性零模型生境异质性

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The Tanh method for Kink Solution of Some modified Nonlinear Equation

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Journal of Partial Differential Equations 2014年第2期27卷 136-142页

作者： FOROZANI Gh GHORVEEI NOSRAT m. Department of Physics Faculty of Science Bu-Ali Sina University Hamedan Iran.

The tanh method is a very powerful technique for computation of exact traveling wave, in this paper this method has been employed for special modified states of Burger, Klein-Gordon and Fisher-Burger equations and the... 详细信息

关键词：非线性方程双曲正切法扭结克莱因汉堡

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Spontaneous Bilateral Carotid Artery Dissection Revealing multifocal Fibromuscular Dysplasia

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Case Reports in Clinical medicine 2019年第9期8卷 250-257页

作者： W. Bnouhanna W. Fakir m. Rahmani m. Benabdeljlil S. A&iuml di Department of Neurology A and Neuropsychology Mohamed V University H&ocirc pital des Spécialités Ibn Sina University Hospital Rabat Morocco

Background: Fibromuscular dysplasia (FmD) is a rare idiopathic segmental non-arteriosclerotic and non-inflammatory arterial disease of small to medium-sized vessels. Although it is considered a benign entity, FmD can lead to potentially severe cerebrovascular complications. We present an atypical clinical case of ischemic stroke (IS) caused by bilateral carotid dissection revealing multifocal FmD. Case Report: A 43-year-old right-handed female with no medical history suddenly developed somnolence with left-sided weakness. Clinical examination revealed left hemiplegia and left central facial paralysis with an NIHSS score: 22. Cerebral tomography (CT) with arterial angiogram revealed abilateralis of the middle cerebral arteries (mCA), a double dissection of the internal carotids (IC), aneurysmal ectasia of the left IC, and aneurysm of the m2 segment of the mCA. Brain magnetic resonance imaging (mRI) with arterial angiography confirmed the bilateral dissection. A cerebral angiography (CA) revealed a radiological pattern of multifocal FmD. The angiography of the aorta and its branches showed adiffuse dysplasia of the renal arteries. The patient was put under antiaggregants. The modified Rankin score (mRS) after three months was three. Conclusion: Cerebrovascular FmD has typical angiographic features, the “string of beads” appearance being the most common. Although the risk of a stroke in patients with cervical FmD is low, it can lead to a severe stroke and the long-term risks are unknown. Patient registries should be encouraged to better understand the mechanisms and evolutionary profile of FmD and alert clinicians to this potentially disabling condition.

关键词： Fibromuscular Dysplasia Carotid Disease Stroke

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粉末冶金mg−B4C复合材料的准静态、动态力学性能及磨损行为

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Transactions of Nonferrous metals Society of China 2021年第2期31卷 371-381页

作者： K.RAHmANI G.H.mAJZOOBI G.EBRAHIm-ZADEH m.KASHFI mechanical Engineering Department Bu-Ali Sina UniversityHamedan 65174Iran Department of Soil Science Faculty of AgricultureGuilan UniversityRasht ***Iran mechanical Engineering Department Ayatollah Boroujerdi UniversityBoroujerd ***Iran

制备体积分数分别为0、1.5%、3%、5%和10%B4C颗粒增强mg金属基复合材料,研究其力学性能和磨损行为。在450℃和不同加载速率下,分别采用分离式霍普金森棒(SHB)、锻锤(DH)和Instron(QS)制备mg−B4C样品,其应变速率分别为1600、800和0.008 ... 详细信息

制备体积分数分别为0、1.5%、3%、5%和10%B4C颗粒增强mg金属基复合材料,研究其力学性能和磨损行为。在450℃和不同加载速率下,分别采用分离式霍普金森棒(SHB)、锻锤(DH)和Instron(QS)制备mg−B4C样品,其应变速率分别为1600、800和0.008 s−1。研究mg−B4C复合材料的显微硬度、准静态及动态抗压强度等力学性能和磨损性能。结果显示,SHB和DH样品的硬度分别比QS样品高20.2%和5.7%。SHB法制备的mg−10.0%B4C样品的磨损率和磨损质量损失分别比QS样品的低33%和39%。与纯mg相比,SHB、DH和QS制备的mg−5.0%B4C样品的准静态抗压强度分别提高39%、30%和29%。此外,含B4C样品的动态抗压强度比准静态抗压强度提高51%~110%。

关键词：粉末压制高应变速率 mg–B4C复合材料硬度力学性能磨损行为

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NON-CHEmICAL CONTROL OF WHEAT FUSARIUm FOOT-ROT BY SOLAR HEAT IN HAmADAN-IRAN

NON-CHEMICAL CONTROL OF WHEAT FUSARIUM FOOT-ROT BY SOLAR HEA...

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The ⅩⅤth International Plant Protection Congress

作者： m.J.SOLEImANI Dept.Plant Protection Faculty of Agriculture Bu-Ali Sina University Hamadan Iran

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