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水平环形翅片管的自然对流参数研究（英文）

Journal of Central South University 2019年第8期26卷 2077-2087页

作者： h. nemati M. MORADAGhAY Department of Mechanics Marvdasht Branch Islamic Azad University Marvdasht Iran Department of Mechanics Shiraz Branch Islamic Azad University Shiraz Iran

对环形翅片管内的自然对流换热进行了数值研究。研究了翅片间距、温差、管径对流动路径和局部传热的影响。结果表明,对于不同的几何形状,PathLines 基本上是圆形的。此外,还明确了翅片周边、翅片侧和裸管对传热的贡献。翅片周边单位面... 详细信息

对环形翅片管内的自然对流换热进行了数值研究。研究了翅片间距、温差、管径对流动路径和局部传热的影响。结果表明,对于不同的几何形状,PathLines 基本上是圆形的。此外,还明确了翅片周边、翅片侧和裸管对传热的贡献。翅片周边单位面积的传热可以是其他零件的数倍。此外,在较大的翅片间距中,来自裸管的热传递比散热片更重要。

关键词：自然对流翅片间距参数化研究环形翅片管

Nano-Fe_3O_4 encapsulated-silica particles bearing sulfonic acid groups as a magnetically separable catalyst for green and efficient synthesis of functionalized pyrimido[4,5-b]quinolines and indeno fused pyrido[2,3-d]pyrimidines in water

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Chinese Chemical Letters 2013年第5期24卷 370-372页

作者： Firouzeh NEMATI Raheleh Saeedirad Department of Chemistry Semnan University

磁性的 nanoparticles 支持了硅石硫磺的酸为 pyrimido 的合成被用作有效催化剂[4,5-b ] 喹啉和 indeno 熔化了 pyrido [2,3-d ] 水里的嘧啶。需要的产品在优秀收益被获得。Fe3O4@SiO2SO3h 乐意地用一个外部磁铁被恢复并且没有反应的重... 详细信息

磁性的 nanoparticles 支持了硅石硫磺的酸为 pyrimido 的合成被用作有效催化剂[4,5-b ] 喹啉和 indeno 熔化了 pyrido [2,3-d ] 水里的嘧啶。需要的产品在优秀收益被获得。Fe3O4@SiO2SO3h 乐意地用一个外部磁铁被恢复并且没有反应的重要损失，能若干次被再使用。

关键词：高效催化剂二氧化硅颗粒嘧啶合成吡啶磁分离磺酸基官能化

Titania Nanostructures for Dye-sensitized Solar Cells

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Nano-Micro Letters 2012年第4期4卷 253-266页

作者： M.Malekshahi Byranvand A.nemati Kharat M.h.Bazargan School of Chemistry University College of Science University of Tehran Iranian Research Organization for Science and Technology (IROST)

Titania is one kind of important materials, which has been extensively investigated because of its unique electronic and optical properties. Research efforts have largely focused on the optimization of the dye,but recently the titania nanostructures electrode itself has attracted more attention. It has been shown that particle size, shape, crystallinity, surface morphology, and chemistry of the TiO_2 material are key parameters which should be controlled for optimized performance of the solar cell. Titania can be found in different shape of nanostructures including mesoporous, nanotube, nanowire, and nanorod structures. The present article reviews the structural, synthesis, electronic, and optical properties of TiO_2 nanostructures for dye sensitized solar cells.

关键词： Titania nanostructures Dye sensitized solar cells Mesoporous Nanotubes Nanowires Nanorods

Zn(NO_3)_2·6h_2O/2,4,6-trichloro-1,3,5-triazine(TCT) a mild and selective system for nitration of phenols

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Chinese Chemical Letters 2010年第4期21卷 403-406页

作者： Firouzeh NEMATI hossein Kiani Department of Chemistry Faculty of ScienceSemnan UniversitySemnanIran

Certain phenols and naphthols were nitrated regioselectively with Zn(NO)·6hO/TCT in acetonitrile as solvent at room temperature and short reaction time in good yields.The reaction condition was mild.TCT is a cheap an... 详细信息

关键词： Nitration Phenols 2 4 6-Trichloro-l 3 5-triazine Regioselective

Synthesis and spectral properties of Nd-doped glass-ceramics in SiO_2-CaO-MgO system prepared by sol-gel method

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Journal of Rare Earths 2013年第6期31卷 595-599页

作者： Masoud Eslami Zohreh hamnabard Ali nemati Materials Science & Engineering Department Sharif University of Technology Materials Research School Ceramic Group

SiO2-CaO-MgO glass and glass-ceramic powder doped with Nd3＋ were synthesized with sol-gel method. Tetraethylorthosilicate （TEOS）, Ca（NO3）2？4h2O, Mg（NO3）2？6h2O, Nd（NO3）3？6h2O, ethanol, distilled water, and hNO3 were used as starting materials. The synthesized powder’s properties were examined with simultaneous thermal analysis （STA）, X-ray diffraction （XRD）, photoluminescence （PL） and scanning electron microscopy （SEM） analysis. The STA curves showed that the softening point and crystallization temperatures were shifted to higher temperatures with increasing dopant content. Regarding XRD patterns of glass samples, Nd was found to act as an intermediate oxide in glass matrix. The XRD patterns of glass-ceramic samples indicated that bredigite and akermanite crystallized in the glass matrix after heat treating at 900 oC. The fluorescence spectra showed that glass-ceramics emitted much stronger irradiation than glasses with the same dopant content. The SEM images illustrated uniform and homogeneous distribution of applied oxides in glass and glass-ceramic compositions.

关键词： glass glass-ceramic synthesis sol-gel method spectral properties rare earths

伊朗稀疏橡木林片段对草本植物物种多样性和土壤特性的边缘影响

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Journal of Plant Ecology 2022年第2期15卷 413-424页

作者： Gelareh Valadi Javad Eshaghi Rad Yahia Khodakarami Mostafa nemati Peykani Karen A.harper Department of Forestry Faculty of Natural ResourcesUrmia UniversitySero BlvdP.O.Box 165UrmiaIran Forests and Rangelands Research Department Agricultural ResearchEducation and Extension Organization(AREEO)Keshavarz BlvdP.O.Box1661-67145 KermanshahIran Biology Department Saint Mary’s University923 Robie streetB3H3c3 HalifaxNSCanada

温带和热带森林中的森林边缘现象已经得到了很好的研究,但在稀疏的橡木林片段中的相关研究却较为缺乏。本文研究了稀疏橡木林片段对植物物种多样性和土壤特性的边缘影响。本研究沿着伊朗克尔曼沙赫省3个小型(10 ha)橡木林片段的3个横断... 详细信息

温带和热带森林中的森林边缘现象已经得到了很好的研究,但在稀疏的橡木林片段中的相关研究却较为缺乏。本文研究了稀疏橡木林片段对植物物种多样性和土壤特性的边缘影响。本研究沿着伊朗克尔曼沙赫省3个小型(ha)和3个大型(>10 ha)橡木林片段的3个横断面收集了从边缘到内部的相关数据,测量了0(森林边缘)、25、50、100和150 m处的草本植物(高度hSD事后检验法的广义线性混合模型评估了距边缘距离和片段大小对多样性和土壤特性的影响。研究结果表明,大小片段边缘具有较高的物种丰富度、多样性和均匀度,而大片段边缘的土壤氮和有机碳含量则较内部更低(边缘50 m范围内的变化最大)。大小片段的物种组成、土壤有机碳和氮总量都存在显著差异。本研究关于这些稀疏森林对草本植物和土壤特性产生显著边缘影响的发现,对于边缘研究,尤其是边缘和草本植物的相关研究具有重大贡献。

关键词：边缘影响扎格罗斯森林大片段栎属植物(Quercus brantii) 小片段

Convective heat transfer from two rotating circular cylinders in tandem arrangement by using lattice Boltzmann method

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Applied Mathematics and Mechanics(English Edition) 2012年第4期33卷 427-444页

作者： h. nemati M. FARhADI K. SEDIGhI M. M. PIROUZ N. N. ABATARI Faculty of Mechanical Engineering Babol Noshirvani University of Technology

The numerical investigation of the two-dimensional laminar flow past two ro- tating circular cylinders in the tandem arrangement is conducted by the lattice Boltzmann method. The numerical strategy is used for dealing with curved and moving boundaries of the second-order accuracy for velocity and temperature fields. The effects of various rotational speed ratios and gap spacing are studied with the Reynolds number of 100 and the Prandtl number of 0.71. A varied range of rotational speed ratios are investigated for four different gap spacing, i.e., 3.0, 1.5, 0.7, and 0.2. The results show that, for the first cylinder, the lift and drag coefficients for large gap spacing are similar to those for a single cylinder; for the second cylinder, the lift coefficient descends with the increase in the angular velocity for all gap spacing, while the drag coefficient ascends except for the gap spacing of 3.0. The results of the averaged periodic Nusselt number on the surface of the cylinders show that, for small distances between the cylinders and low angular velocities, conduction is a dominant mechanism of heat transfer, but for large distances and high angular velocities, convection is the main mechanism of heat transfer.

关键词： lattice Boltzmann method rotating circular cylinder laminar flow curvedand moving boundary

Improvements in the microstructure and fatigue behavior of pure copper using equal channel angular extrusion

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International Journal of Minerals,Metallurgy and Materials 2014年第6期21卷 569-576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 Universiti Putra Malaysia School of Mechanics Islamic Azad UniversityTakestan Branch348194 9479 Takestan Iran

In this study, annealed pure copper was extruded using equal channel angular extrusion （ECAE） for a maximum of eight passes. The fatigue resistance of extruded specimens was evaluated for different passes and applied stresses using fatigue tests, fractography, and metallography. The mechanical properties of the extruded material were obtained at a tensile test velocity of 0.5 mm/min. It was found that the maximum increase in strength occurred after the 2nd pass. The total increase in ultimate strength after eight passes was 94%. The results of fatigue tests indicated that a significant improvement in fatigue life occurred after the 2nd pass. In subsequent passes, the fatigue life con-tinued to improve but at a considerably lower rate. The improved fatigue life was dependent on the number of passes and applied stresses. For low stresses （or high-cycle fatigue）, a maximum increase in fatigue resistance of approximately 500%was observed for the extruded material after eight passes, whereas a maximum fatigue resistance of 5000%was obtained for high-applied stresses （or low-cycle fatigue）. Optical microscopic examinations revealed grain refinements in the range of 32 to 4 μm. A maximum increase in impact energy absorption of 100%was achieved after eight passes. Consistent results were obtained from fractography and metallography examinations of the ex-truded material during fatigue tests.

关键词： copper equal channel angular extrusion fatigue of materials grain size grain refinement fracture toughness

Specific serum immunoglobulin G to h pylori and CagA in healthy children and adults(south-east of Iran)

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World Journal of Gastroenterology 2007年第22期13卷 3117-3121页

作者： A Jafarzadeh MT Rezayati M nemati Department of Immunology Medical School Rafsanjan University of Medical Sciences Rafsanjan Iran

AIM: To evaluate the serologic IgG response to h pylori and CagA across age groups and in healthy children and adults. METhODS: Totally, 386 children aged 1-15 years and 200 adults aged 20-60 years, were enrolled to study. The serum samples of participant were tested for presence of anti-h pylori and anti-CagA IgG by using ELISA method. RESULTS: The seroprevalence of h pylori in adults was signif icantly higher than that observed in children (67.5/ vs 46.6/; P hildren, the seropositivity rate in males (51.9/) was signifi cantly (P higher than that observed in females (41.7/). The prevalence of serum anti-CagA antibody was 72.8/ and 67.4/ in infected children and adults, respectively. The mean titer of serum anti-CagA antibodies was significantly higher among children in comparison to adults (64.1 Uarb/mL vs 30.7; P hildren and adults the prevalence of serum anti-CagA antibody was higher in males compared to females (78.4/ vs 66.3/; P = 0.07 and 75.6/ vs 54.71/; P he age-specific prevalence of anti-h pylori and anti-CagA antibody (in infected subjects) was 37.6/ and 59.57/ at age 1-5 years, 46.9/ and 75/ at age 6-10 years, 54.9/ and 79.45/ at age 11-15, 59.01/ and 83.33/ at age 20-30 years, 66.6/ and 60.52/ at age 31-40 years, 73.46/ and 63.88/ at age 41-50 years and 75.75/ and 60/ at age 51-60 years with mean titer of anti-CagA antibody of 75.94, 63.32, 57.11, 52.06, 23.62, 21.52 and 21.80 Uarb/mL, respectively. There was significant difference between mean serum anti-CagA antibody in age subgroups (P hese results showed that anti-h pylori and anti-CagA antibodies were common in the children and adults. The h pylori-specifi c antibodies influenced by age and sex of subjects. Moreover, it seems that malesare more susceptible to infection with CagA+ strains compared to females. The seroprevalence of anti-CagA antibody was increased with age, up to 30 years and then decreased. It was also found that the magnitude of the IgG

关键词：伊朗幽门螺杆菌儿童成年人血清免疫球蛋白G 免疫保护力抗体