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Lattice Boltzmann method formulation for simulation of thermal radiation effects on non-Newtonian Al_(2)O_(3) free convection in entropy determination

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Applied mathematics and mechanics(English Edition) 2024年第6期45卷 1085-1106页

作者： m.nemati m.SEFID A.KARImIPOUR A.J.CHAmKHA Faculty of mechanical Engineering Yazd UniversityYazd ***Iran Department of mechanical Engineering Najafabad BranchIslamic Azad UniversityNajafabad ***Iran Faculty of Engineering Kuwait College of Science and TechnologyDoha 35004Kuwait

The simultaneous investigation on the parameters affecting the flow of electrically conductive fluids such as volumetric radiation,heat absorption,heat generation,and magnetic field(mF)is very vital due to its existence in various sectors of industry and engineering.The present research focuses on mathematical modeling to simulate the cooling of a hot component through power-law(PL)nanofluid convection flow.The temperature reduction of the hot component inside a two-dimensional(2D)inclined chamber with two different cold wall shapes is evaluated.The formulation of the problem is derived with the lattice Boltzmann method(LBm)by code writing via the FORTRAN language.The variables such as the radiation parameter(0–1),the Hartmann number(0–75),the heat absorption/generation coefficient(−5–5),the fluid behavioral index(0.8–1.2),the Rayleigh number(103–105),the imposed mF angle(0°–90°),the chamber inclination angle(−90°–90°),and the cavity cold wall shape(smooth and curved)are investigated.The findings indicate that the presence of radiation increases the mean Nusselt number value for the shear-thickening,Newtonian,and shear thinning fluids by about 6.2%,4%,and 2%,respectively.In most cases,the presence of nanoparticles improves the heat transfer(HT)rate,especially in the cases where thermal conduction dominates convection.There is the lowest cooling performance index and mF effect for the cavity placed at an angle of 90°.The application in the design of electronic coolers and solar collectors is one of the practical cases of this numerical research.

关键词： thermal performance analysis heat absorption/generation power-law(PL)Al_(2)O_(3)nanofluid magnetohydrodynamics natural convection volumetric radiation inclined cavity

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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 males (51.9/) was signifi cantly (P males (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 m 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 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 mmon 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

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生物形成的碳酸钙——一种用于提高原油采收率的长效堵塞剂

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国外石油动态 2004年第11期 8-11页

作者： m.nemati Voordouw 廉抗利

用间歇式系统研究了生物形成的碳酸钙(用纯尿素酶或由加拿大油田离析出来的细菌生成的尿素酶催化)。酶生成的CaCO3，的程度随着酶和试剂浓度以及温度的增加而增加。在有细菌存在的情况下，生成的CaCO3数量取决于尿素浓度，用15g／L尿素... 详细信息

用间歇式系统研究了生物形成的碳酸钙(用纯尿素酶或由加拿大油田离析出来的细菌生成的尿素酶催化)。酶生成的CaCO3，的程度随着酶和试剂浓度以及温度的增加而增加。在有细菌存在的情况下，生成的CaCO3数量取决于尿素浓度，用15g／L尿素获得了最高数量。酶生成的CaCO3的最大浓度(57．6g／L)比有细菌存在的情况下获得的浓度(21．5g/L)高2．6倍。细菌生成的CaCO3对温度不太敏感，而尿素酶的CaCO3产量随着温度从20℃上升到50℃而被提高。疏松多孔介质和贝雷砂岩岩心驱替系统的堵塞研究指出，CaCO3在原地地层能够有效降低多孔介质的渗透率并可用作提高原油采收率作业的有效方法。

关键词：碳酸钙原油采收率堵塞剂试剂浓度渗透率硅酸钙温度岩心驱替系统

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Simulation and optimization of an industrial gas condensate stabilization unit to modify LPG and NGL production with minimizing CO2 emission to the environment

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Chinese Journal of Chemical Engineering 2017年第3期25卷 338-346页

作者： m.Bahmani J.Shariati A.nemati Rouzbahani Young Researchers and Elite Club Darab BranchIslamic Azad UniversityDarabIran Department of Chemical Engineering Darab BranchIslamic Azad UniversityDarabIran

In the present study, a great effort was made to improve the performance of an industrial liquefied petroleum gas(LPG) and natural gas liquid(NGL) production unit in one of the major gas refinery located at Pars special economic zone in Iran. To demonstrate and obtain the optimal condition, the unit was simulated by using a steady-state flowsheet simulator, i.e. Aspen Plus, under different operational conditions. According to the simulation results,the unit was not operational under its optimal conditions due to some defects in the cooling system at top stage of the debutanizer tower(DBT) during hot and humid seasons. Additionally, the vapor pressure of produced LPG and accordingly the amount of its flaring were decreased by reducing the temperature of debutanizer tower at top stages. In the optimization section, the DBT condenser and reboiler heat duty, temperature, and pressure were regulated as adjustable parameters. The simulation results demonstrated that by applying the optimum suggestion in the hot months, the reflux stream temperature was reached about 55 ℃ which caused an efficient increment in LPG production(about 4%) with adjusting the propane component in LPG, based on the standard range as the plant criteria. moreover, after applying modifications, about 750 t of LPG product was saved from flaring during five hot months of the year, which resulted in 360000 USD extra annual income for the company.Finally, from environmental point of view, this optimization caused to reduce 81 t of CO_2 emission to the environment. Therefore, the current investigation must be introduced as a friendly environmentally process.

关键词： LPG NGL Simulation Optimization CO2 emission

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mechanical and wear properties of Al-Al_3mg_2 nanocomposites prepared by mechanical milling and hot pressing

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International Journal of minerals,metallurgy and materials 2013年第3期20卷 290-297页

作者： A. Zolriasatein R.A. Khosroshahi m. Emamy N. nemati Faculty of materials Engineering Sahand University of Technology Center of Excellence for High Performance materials School of Metallurgy and Materials University of Tehran

β-A13mg2 intermetallic was used as a reinforcing agent to improve the mechanical properties of an aluminum matrix. Different amounts of A13mg2 nanoparticles （ranging from 0wt% to 20wt%） were milled with aluminum powders in a planetary ball mill for 10 h. Consolidation was conducted by uniaxial pressing at 400β under a pressure of 600 mPa for 2 h. microstructural characterization confirms the uniform distribution of A13mg2 nanoparticles within the matrix. The effects of nano-sized A13mg2 content on the wear and mechanical properties of the composites were also investigated. The results show that as the A13mg2 content increases to higher levels, the hardness, compressive strength, and wear resistance of the nanocomposites increase significantly, whereas the relative density and ductility decrease. Scanning electron microscopy （SEm） analysis of worn surfaces reveals that a transition in wear mechanisms occurs from delamination to abrasive wear by the addition of A13mg2 nanoparticles to the matrix.

关键词： nanocomposites intermetallics mechanical milling hot pressing wear compressive strength hardness

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Catalytic evaluation of promoted CeO_2-ZrO_2 by transition, alkali, and alkaline-earth metal oxides for diesel soot oxidation

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Journal of Environmental Sciences 2013年第12期25卷 2498-2506页

作者： Ali Alinezhadchamazketi Abas Ali Khodadadi Yadollah mortazavi Ahmad nemati Catalysis and Nanostructured materials Laboratory College of EngineeringSchool of Chemical EngineeringUniversity of Tehran Oil and Gas Processing Center of Excellence College of EngineeringUniversity of Tehran

Series of mixed metal oxides were synthesized by gel-combustion method and their catalytic activities for soot oxidation were investigated. The catalysts were m-Ce-Zr （m = mn, Cu, Fe, K, Ba, Sr）, and χK-20mn-Ce-Zr （χ= 0, 5, 10, 20）, they were characterized by XRD, SEm, TPR and BET surface area techniques. The results of soot temperature programmed oxidation （TPO） in an O2 oxidizing atmosphere indicate that K-Ce-Zr has the highest catalytic activity for soot oxidation under loose contact condition, due to enhancement of the soot and catalyst contacts. On the other hand, under a tight contact condition, mn-Ce-Zr and Cu-Ce-Zr nano-composites have high activities for soot oxidation and lower the soot TPO peak temperatures by about 280 and 270℃, respectively, as compared to non-catalytic soot oxidation. Furthermore, the addition of up to 10 wt.% potassium oxides into mn-Ce-Zr increases its catalytic activity and further reduces the soot TPO peak temperature by about 40℃ under loose contact condition.

关键词： soot oxidation diesel ceria-zirconia metal oxide

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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

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Leishmania tropica: The comparison of two frequently-used methods of parasite load assay in vaccinated mice

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Asian Pacific Journal of Tropical Biomedicine 2020年第6期10卷 248-253页

作者： Fatemeh nemati Zargaran mosayeb Rostamian Alisha Akya Hamid mNiknam Infectious Diseases Research Center Health InstituteKermanshah University of Medical SciencesKermanshahIran Immunology Department Pasteur Institute of Iran69 Pasteur AvenueTehran 13169-43551Iran

Objective:To compare limiting dilution assay and real-time PCR methods in Leishmania tropica parasite load measurement in vaccinated mice.methods:BALB/c mice were vaccinated by Leishmania tropica soluble Leishmania antigen or recombinant Leishmania tropica stressinducible protein-1 with/without adjuvant.After three vaccinations,mice were challenged by Leishmania tropica promastigotes.Two months after challenge,the draining lymph nodes of mice footpad were removed and parasite load was assayed by limiting dilution assay and real-time PCR methods.Limiting dilution assay was done by diluting tissue samples to extinction in a biphasic medium.For real-time PCR,DNA of the lymph nodes was extracted,equal dilutions of each sample were prepared and hot-start real-time PCR was done using appropriate primers.The data of the two methods were compared by appropriate statistical methods.Results:Both methods were able to measure different levels of parasite load in vaccinated/unvaccinated mice.In addition,wherever parasite load of a group was estimated high(or low)by one method,the estimated parasite load by another method was the same,although statistically significant differences were found between some groups.Conclusions:Both methods lead to approximately similar results in terms of differentiating parasite load of the experimental groups.However,due to the lower errors and faster process,the real-time PCR method is preferred.

关键词： Leishmania tropica Vaccinated mice Limiting dilution assay Parasite load assay,Real-time PCR

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Design of mmIC oscillators using GaAs 0.2 μm PHEmT technology

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第10期13卷 793-798页

作者： Neda KAZEmY NAJAFABADI Sare nemati massoud DOUSTI Department of Electrical Engineering Arak BranchIslamic Azad UniversityArakIran Department of Electrical Engineering Science and Research BranchIslamic Azad UniversityTehranIran

We propose a feedback type oscillator and two negative resistance oscillators.These microwave oscillators have been designed in the S band frequency.A relatively symmetric resonator is used in the feedback type oscillator.The first negative resistance oscillator uses a simple lumped element resonator which is substituted by a microstrip resonator in the second oscillator to improve results.The negative resistance oscillator produces 4.207 dBm and 7.124 dBm output power with the lumped element resonator and microstrip resonator respectively,and the feedback type oscillator produces ?10.707 dBm output power.The feedback type oscillator operates at 3 GHz with phase noise levels at-83.30 dBc/Hz and-103.3 dBc/Hz at 100 kHz and 1 mHz offset frequencies respectively.The phase noise levels of the negative resistance oscillator with the lumped element resonator are-94.64 dBc/Hz and-116 dBc/Hz at 100 kHz and 1 mHz offset frequencies respectively,at an oscillation frequency of 3.053 GHz.With the microstrip resonator the phase noise levels are-99.49 dBc/Hz and-119.641 dBc/Hz at 100 kHz and 1 mHz offset frequencies respectively,at an oscillation frequency of 3.072 GHz.The results showed that both the output power and the phase noise of the negative resistance oscillators were better than those of the feedback type oscillator.

关键词： microwave oscillator Feedback type Negative resistance Resonator Advanced design system software

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microwave assisted synthesis & properties of nano HA-TCP biphasic calcium phosphate

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International Journal of minerals,metallurgy and materials 2012年第5期19卷 441-445页

作者： E.Ghomash Pasand A.nemati m.Solati-Hashjin K.Arzani A.Farzadi Department of materials Engineering Science and Research BranchIslamic Azad UniversityTehran ***Iran Department of Biomedical Engineering Amirkabir University of TechnologyTehran 158754413Iran

Biphasic calcium phosphate （BCP） nanopowders were synthesized by using microwave and non-microwave irradiation assisted processes. The synthesized powders were pressed under a pressure of 90 mPa, and then were sintered at 1000-1200℃ for 1 h. The mechanical properties of the samples were investigated. The formed phases and microstructures were characterized by X-ray diffraction （XRD） and scanning electron microscopy （SEm）. The results showed that the synthesis time was shorter, along with a more homogeneous microstructure, when the microwave irradiation assisted method was applied. The compression strength and the Young＇s modulus of the samples synthesized with microwave irradiation were about 60 mPa and 3 GPa, but those of the samples synthesized without microwave irradiation were about 30 mPa and 2 GPa, respectively. XRD patterns of the microwave irradiation assisted and non-microwave irradiation assisted nanopowders showed the coexistence of hydroxyapatite （HA） and lricalcium phosphate （TCP） phases in the system.

关键词： bioceramics calcium phosphate hydroxyapatite （HA） Wicalcium phosphate nanoparticles （TCP） mechanical properties microwave irradiation

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