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Optimal Operation and Size for an Energy Hub with CCHP

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Energy and Power Engineering 2011年第5期3卷 641-649页

作者： Ali Mohammad Ranjbar Amir Moshari Hashem Oraee aras sheikhi 不详

The interest in distributed generation has been increasing in recent years, especially due to technical devel- opment on generation systems that meet environmental and energy policy concerns. One of the most impor- tant distributed energy technologies is Combined Cooling, Heat and Power (CCHP) systems. CCHP is a small and self-contained electric, heating and cooling generation plant that can provide power for households, commercial or industrial facilities. It can reduce power loss and enhance service reliability in distribution systems. The proposed method in this paper determines the optimal size and operation of CCHP, auxiliary boiler and also heat storage unit as elements of an energy hub, for users by an integrated view of electricity and natural gas network. Authors apply cost and benefit analysis in the optimization. To confirm the proposed method, the optimum sizes of these elements are determined for a hotel in Tehran as a case study.

关键词： Combined Cooling Heating And Power (CCHP) Cost And Benefit Analysis Energy Hub Optimal Operation Optimal Size

Developing an engineering-statistical model for estimating aerodynamic coefficients of helicopter fuselage

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Chinese Journal of Aeronautics 2017年第1期30卷 175-185页

作者： Hossein sheikhi Abas Saghaie Department of Industrial Engineering Science and Research Branch Islamic Azad University

The design of the geometric shape of a helicopter fuselage poses a serious challenge for designers. The most important parameter in determining the shape of the helicopter fuselage is its aerodynamic coefficients. These coefficients are determined using two methods： wind tunnel test and computational fluid dynamics（CFD） simulation. The first method is expensive, time-consuming and limited. In addition, estimates in regions away from data can be poor. The second method,due to the limitations of numerical solution, the number of nodes and the used solution, is often inaccurate. In this paper, with the aim of accelerating the design process and achieving results with reasonable engineering accuracy, an engineering-statistical model which is useful for estimating the aerodynamic coefficients was developed, which mitigated the drawbacks of these two ***, by combining CFD simulation and regression techniques, an engineering model was presented for the estimation of aerodynamic coefficients. Then, by using the data from a wind tunnel test and implementation of statistical adjustment, the engineering model was modified and an engineering-statistical model was obtained. By spending less time and cost, the final model provided the aerodynamic coefficients of a helicopter fuselage at the desired angles of attack with reasonable accuracy. Finally, three numerical examples were provided to illustrate the application of the proposed model. Comparative results demonstrate the effectiveness of the engineering-statistical model in estimating the aerodynamic coefficients of a helicopter fuselage.

关键词： Aerodynamic coefficients Computaticnal fluid dynamics (CFD) Engineering-statistical model Helicopter fuselage Wind tunnel test

Kinetic study on leaching of nickel from Turkish lateritic ore in nitric acid solution

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Journal of Central South University 2016年第1期23卷 39-43页

作者： Tevfik AGACAYAK Veysel ZEDEF Ali aras Department of Mining Engineering Faculty of EngineeringSelcuk University

Dissolution kinetics of nickel from lateritic ore in nitric acid solution was investigated. Experimental parameters used were stirring speed(100-600 r/min), temperature(40-96 °C), nitric acid concentration(0.1-2 mol/L) and particle size(<106 μm). The shrinking core model was applied to the results of experiments investigating the effects of leaching temperature in the range of 40-90 °C and nitric acid concentration in range of 0.1-2 mol/L on nickel dissolution rate. The kinetic analysis shows that the nickel dissolution from lateritic ore could be described by diffusion model. The activation energy(E_a) for the dissolution reaction is calculated as 79.52 kJ/mol.

关键词： leaching lateritic ore nickel kinetic analysis diffusion nitric acid

Numerical Analysis of Crack-Tip Fields using a Meshless Method in Linear Elastic Materials

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Advances in Applied Mathematics and Mechanics 2022年第6期14卷 1509-1534页

作者： Zahra sheikhi Akbar Ghanbari Mohammad Karkon Soleyman Ghouhestani Department of Civil Engineering Larestan BranchIslamic Azad UniversityLarestanIran Department of Civil Engineering Fasa UniversityFasaIran

In this paper,the Discrete Least Squares Meshless(DLSM)method is developed to determine crack-tip *** DLSM,the problem domain and its boundary are discretized by unrelated field nodes used to introduce the shape functions by the moving least-squares(MLS)*** method aims to minimize the sum of squared residuals of the governing differential equations at any nodal *** high-continuity shape functions are used,some necessary treatments,including the visibility criterion,diffraction,and transparency approaches,are employed in the DLSM to introduce strong discontinuities such as *** stress extrapolation and J-integral methods are used to calculate stress intensity *** classic numerical examples using three approaches to defining discontinuities in the irregular distribution of nodal points are considered to investigate the effectiveness of the DLSM *** numerical tests indicated that the proposed method effectively employed the approaches to defining discontinuities to deal with discontinuous *** was also demonstrated that the diffraction approach obtained higher accuracy than the other techniques.

关键词： Numerical analysis partial differential equations fracture mechanics meshless method discrete least-squares modification of weight function approaches to defining discontinuities stress intensity factors.

Assessment of air pollution genotoxicity by RAPD in Evernia prunastri L. Ach. from around iron-steel factory in Karabk, Turkey

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Journal of Environmental Sciences 2011年第7期23卷 1171-1178页

作者： Demet Cansaran-Duman Orhan Atakol Smer aras Refik Saydam National Public Health Agency Drug and Cosmetics Research Department Laboratories Department of Chemistry Faculty of Science University of Ankara Biotechnology Section Department of Biology Faculty of Science University of Ankara

Lichens are widely used in biomonitoring studies of air pollution, either as bioindicators of air quality or as bioaccumulators of atmospheric deposition. Over the past decade, several molecular techniques have been developed to provide information on diversity, genotoxicology, genetic relationships, etc. The heavy metal contents of Evernia prunastri samples were determined by atomic absorption spectrometry. The Random Amplified Polymorphic DNA Polymerase Chain Reaction （RAPD-PCR） method was used to describe the pattern of DNA band variation in the samples influenced by the environmental pollution. The study was designed to describe the level of pollution in an area contaminated with smoke and waste from an iron-steel factory, and to reveal the level of potential genotoxic agents around this source of pollution. The study also examined the suitability of the lichen samples for the detection of genotoxicity.

关键词： air pollution Evernia prunastri RAPD genotoxicity

1-Methylimidazole-catalyzed reaction between tosylmethyl isocyanide and dialkyl acetylenedicarboxylates:An efficient synthesis of functionalized pyrroles

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Chinese Chemical Letters 2011年第3期22卷 314-317页

作者： Mehdi Adib Bagher Mohammadi Ehsan sheikhi Hamid Reza Bijanzadeh School of Chemistry University College of ScienceUniversity of TehranPO Box 14155-6455TehranIran Department of Chemistry Tarbiat Modarres UniversityPO Box 14115-175TehranIran

An efficient 1-methylimidazole-catalyzed synthesis of dialkyl 2-[（4-methylphenyl）sulfonyl]-1H-pyrrole-3,4-dicarboxylates is *** reactive 1：1 zwitterionic intermediate formed by the addition of 1-methylimidazole to dialkyl acetylenedicarboxylates is trapped by tosylmethyl isocyanide（TOSMIC） to afford the title compounds in excellent yields.

关键词： 1-Methylimidazole Tosylmethyl isocyanide Acetylenic esters Pyrrole synthesis

Theoretical Study of Interaction between Apalutamide Anticancer Drug and Thymine by DFT Method

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Chinese Journal of Structural Chemistry 2019年第10期38卷 1645-1663,1609页

作者： SIYAMAK Shahab MASOOME sheikhi MEHRNOOSH Khaleghian SHAMSA Sharifi SADEGH Kaviani Institute of Physical Organic Chemistry National Academy of Sciences of Belarus13 Surganov StrMinsk 220072Republic of Belarus Institute of Chemistry of New Materials National Academy of Sciences of Belarus36 Skarina Str.Minsk 220141Republic of Belarus Belarusian State University IS El BSUMinskRepublic of Belarus Young Researchers and Elite Club Gorgan BranchIslamic Azad UniversityGorganIran Young Researchers and Elite Club Islamshahr BranchIslamic Azad UniversityIslamshahrIran Department of Chemistry Robat Karim BranchIslamic Azad UniversityRobat KarimIran Department of Chemistry Ferdowsi University of MashhadMashhadIran

The main purpose of this study is a better comprehension of the non-bonded interaction between an anticancer drug apalutamide and deoxyribonucleic acid(DNA).In the prese nt work,the in teraction between an ticancer drug apalutamide and one of the DNA bases called 2,-deoxythymidine 5,-monophosphate(thymine)by Density Functional Theory(DFT)calculations in the solvent water has been investigated for the first *** non-bonded interaction effects of the molecule apalutamide with thymine on the electronic properties,chemical shift tensors and natural charges have been also *** natural bond orbital(NBO)analysis was performed for determining the role of electron donor and acceptor of the molecules apalutamide and thymine at the complex thymine/*** Electron location function(ELF),localized orbital locator(LOL)and quantum theory of atoms in molecules(QTAIM)analysis were carried out in order to determine the chemical bond nature in the investigated *** values of ELF and LOL parameters for the selected bonds are small,which confirms the non-covalent character of these bonds in *** electronic spectra of the apalutamide drug,thymine and complex thymine/apalutamide in solvent water were calculated by Time Dependent Density Functional Theory(TD-DFT)for the investigation of interaction effect;Non-bonded interaction between the compound apalutamide and thymine has changed the value of λmax.

关键词： apalutamide thymine DFT ELF NBO

Effect of Sinter Hardening on Microstructure and Mechanical Properties of Astaloy 85Mo

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Journal of Iron and Steel Research International 2012年第10期19卷 43-46页

作者： K sheikhi Moghaddam M Ghambari H Farhangi N Solimanjad School of Metallurgy and Materials Engineering College of Engineering University of TehranTehran11155-4563Iran Hgans AB Hgans SE-263 83Sweden

Effect of sinter hardening on the microstructure, density, hardness and tensile properties of Astaloy 85Mo+0.7% graphite was investigated. For this purpose, Astaloy 85Mo, a pre-alloyed powder, was mixed with 0.7% UF4 graphite and then pressed in single action die and sintered at 1 120 ℃ for 30 min in N2-10%H2 atmosphere. Then samples were cooled from 0.5 to 3 ℃/s sintering temperature in accordance with different cooling rates. The difference in microstructure, hardness, density and tensile properties of the samples associated with different cooling rates from sintering temperature has been investigated. The results show that the microstructure remains bainitic by changing cooling rate, but it becomes finer and then the hardness and tensile strength of the samples will increase by increasing the cooling rate from sintering temperature.

关键词： sinter hardening Astaloy 85Mo cooling rate bainitic microstructure

Sublethal effects of hexaflumuron on development and reproduction of the diamondback moth, Plutella xylostella （Lepidoptera： Yponomeutidae）

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Insect Science 2011年第6期18卷 689-696页

作者： Mohammad Mahmoudvand Habib Abbasipour Aziz sheikhi Garjan Ali Reza Bandani Department of Plant Protection Faculty of Agricultural Sciences Shahed University Tehran Iranian Research Institute of Plant Protection Tehran Department of Plant Protection College of Agriculture and Natural Resources University of Tehran Karaj Islamic Azad University Qom branch Young Researches Club Qom Iran

Effects of hexaflumuron at 10% lethal concentration （LC10） and LC25 on development and reproduction parameters of the diamondback moth, Plutella xylostella （Linnaeus, 1753）（Lep.： Yponomeutidae） were investigated. Estimated LC50, LC10 and LC25 values of leaf dip bioassay of hexaflumuron on the third instar larvae of the P xylostella were 1.48, 0.59 and 0.91 mg/L, respectively. Hexaflumuron decreased pupal weight in the parent generation at sublethal concentrations but in the offspring generation, this effect was not observed. Sublethal concentrations increased egg, first and second larval instar and pupa developmental time and shortened life span of adults, but did not change the third and fourth larval instars and pre-pupa developmental period. Also fecundity of females reduced significantly but hatchability of treatments and control were similar. Survival rate of pre-adult stages declined significantly at LC25 concentration. Reproduction parameters such as reproductive rate （R0） and intrinsic rate of increase in sublethal concentrations were significantly lower compared with control, but gross reproduction rate （GRR） at the LC10 concentration was increased and it could be hormoligosis. Also hexaflumuron significantly increased doubling time （Dt）. We conclude that the sublethal effects of hexaflumuron might exhibit significant effects on the population dynamics of P xylostella.

关键词： biological parameters diamondback moth hormoligosis IGR Plutella xylostella sublethal concentrations