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Zoning of Nitrite and Nitrate Concentration in Groundwater Using Geografic Information System (GIS), Case Study: Drinking Water Wells in Yazd City

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Journal of Geoscience and Environment Protection 2016年第3期4卷 91-96页

作者： Reza ali Fallahzadeh seyed ali almodaresi Mohamad Mehdi Dashti Ahmad Fattahi Mojtaba Sadeghnia Hadi Eslami Rasoul Khosravi Roya Peirovi Minaee Mahmoud Taghavi Department of Environmental Health Engineering Faculty of Public Health Shahid Sadoughi University of Medical Sciences Yazd Iran Department of GIS & RS Engineering College Yazd Branch Islamic Azad University Yazd Iran Department of Occupational Health Engineering School of Public Health Shahid Sadoughi University of Medical Sciences Yazd Iran Department of Environmental Health Engineering Zabol University of Medical Sciences Zabol Iran

Studies have demonstrated that the presence of nitrate and nitrite in drinking water can cause some disease such as cancer and blu baby in the infant. The Environmental Protection Agency (EPA) has since adopted the 10 mg/L standard as the maximum contaminant level (MCL) for nitrate-nitrogen and 1 mg/L for nitrite-nitrogen for regulated public water systems. Given the importance of nitrate and nitrite in drinking water as well as GIS ability in spatial analysis of various factors in the groundwater, this study aimed to evaluate concentration of nitrate and nitrite in the drinking water wells of Yazd using two IDW (Inverse Distance Weighting) and Kriging models. In this descriptive study, the applied data on the water quality of underground water of Yazd Environmental Health Office and the average annual nitrate and nitrite in 2015 were related to 24 wells in the studied area. The nitrate and nitrite rate in groundwater in wells was compared to the standard amount of Institute of Standard and Industrial Researches and then was analyzed via Arc GIS software using IDW and Kriging interpolation methods. The mean concentration of nitrate was 17.62 ± 3.08 mg/l and for nitrite was 0.011 ± 0.003 mg/l in the wells. In the all studied zone, the nitrate and nitrite rate was in the standard range according to the National Standard of Iran (No. 1053). In this study, Kriging interpolation method was more efficient than IDW method.

关键词： Drinking Water Nitrite and Nitrate Concentration Geographic Information Systems Interpolation

Sacrificial piles as a countermeasure against local scour around underwater pipelines

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Water Science and Engineering 2024年第2期17卷 187-196页

作者： Forough Raeisi seyed Mohammad ali Zomorodiann Masih Zolghadr Hazi Mohammad Azamathulla Department of Water Engineering Shiraz UniversityShiraz ***Iran Department of Water Sciences Engineering Jahrom UniversityJahrom ***Iran Department of Civil and Environmental Engineering The University of the West IndiesSt.Augustine CampusTrinidad 331310Republic of Trinidad and Tobago

Local scour around pipelines crossing rivers or in marine environments is a significant *** can lead to failure of the pipelines resulting in environmental side effects and economic *** study developed an experimental method to reduce local scour around pipelines with a steady flow of clear water by installing cylindrical and cubical sacrificial *** sizes of sacrificial piles were examined in a linear *** piles were installed on the upstream side of the pipeline at three *** scour depth reduction rates below the pipeline were *** results showed that sacrificial piles could protect a pipeline from local scour.A portion of scoured sediment around the sacrificial piles was deposited beneath the *** sediment accumulation reduced the scour depth beneath the *** of the experimental results demonstrated that the size of piles(d),the spacing between piles,and the distance between the pipe and piles(Xp)were the variables that reduced the maximum scour beneath the pipeline with a diameter of *** the piles with d=0.40D and 0.64D,X_(p)=4OD was the optimal distance to install a group of piles,and cubical piles could mitigate scour more effectively than cylindrical piles under similar *** the piles with d=D,the greatest reduction in scour depth was achieved at X_(p)=50D with any desired spacings between piles,and cylindrical piles in this dimension could protect the pipeline against scour more effectively than cubical piles.

关键词： Clear water River crossing pipeline Local scour Self-burial process Sediment transport

Numerical study of convective heat transfer in static arrangements of particles with arbitrary shapes:A monolithic hybrid lattice Boltzmann-finite difference-phase field solver

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Particuology 2024年第2期85卷 186-197页

作者： Reza Namdar Mohammadhassan Khodsiani Hesameddin Safari Tanya Neeraj seyed ali Hosseini Frank Beyrau Benoit Fond Dominique Thevenin Fathollah Varnik Interdisciplinary Centre for Advanced Materials Simulation(ICAMS) Ruhr-University BochumBochum44801Germany Laboratory of Technical Thermodynamics University of Magdeburg"Otto von Guericke"Magdeburg39106Germany Laboratory of Fluid Dynamics and Technical Flows University of Magdeburg"Otto von Guericke"MagdeburgD-39106Germany Department of Mechanical and Process Engineering ETH ZurichZurich8092Switzerland ONERA The French Aerospace Lab Department of AerodynamicsAeroelasticity and Acoustics(DAAA)Paris-Saclay UniversityMeudon92190France

A compressible lattice Boltzmann-finite difference method is extended by the phase-field approach into a monolithic scheme to study fluid flow and heat transfer through regular arrangements of solid bodies of circular,elliptical and irregular *** advantage of using the phase-field method is demon-strated both in its simplicity of accounting for flow and thermal boundary conditions at solid surfaces with irregular shapes and in the capability of generating such complex-shaped *** an array of discs,numerical results for the overall solid-to-gas heat transfer rate are validated via experiments on flow through arrays of hot *** thus validated compressible LB-FD-PF hybrid scheme is used to study the dependence of heat transfer on flow and thermal boundary conditions(Reynolds number,temperature difference between the hot solid bodies and the inlet gas),porosity as well as on the shape of solid *** are rationalized in terms of the residence time of the gas close to the solid body and downstream variations of gas velocity and *** for further applications of the proposed methodology are also discussed.

关键词： Lattice Boltzmann method Finite difference scheme Convective heat transfer Diffuse interface Thermal compressible flow

Assessment of fracture process in forta and polypropylene fiber-reinforced concrete using experimental analysis and digital image correlation

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Frontiers of Structural and Civil Engineering 2022年第12期16卷 1633-1652页

作者： seyed Hamid KALali Hamid ESKANDARI-NADDAF seyed ali EMAMIAN Department of Civil Engineering Hakim Sabzevari UniversitySabzevar ***Iran

This paper aims to characterize the evolution of the fracture process and the cracking behavior in fortaferro(FF)and polypropylene(PP)fiber-reinforced concrete under the uniaxial compressive loading using experimental analysis and digital image correlation(DIC)on the surface *** this purpose,6 mix designs,including two FF volume fractions of 0.10%,and 0.20%and three PP volume fractions of 0.20%,0.30%,and 0.40%,in addition to a control mix were evaluated according to compressive strength,modulus of elasticity,toughness index,and stress–strain *** influence of fibers on the microstructural texture of specimens was analyzed by scanning electron microscope(SEM)*** show that FF fiber-reinforced concrete specimens demonstrated increased ductility and strength compared to PP *** results revealed that the major crack and fracture appeared at the peak load of the control specimen due to brittleness and sudden gain of large lateral strain,while a gradual increase in micro-crack quantity at 75%of peak load was observed in the fiber specimens,which thenbegan to connect with each other up to the final *** accuracy of the results supports DIC as a reliable alternative for the characterization of the fracture process in fiber-reinforced concrete.

关键词： fiber-reinforced concrete forta-ferro and polypropylene fiber fracture process cracking behavior digital image correlation

Numerical analysis of reactive turbulent flow in the thrust chamber of RD-108 engine rocket

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Defence Technology（防务技术） 2019年第4期15卷 565-575页

作者： seyed Reza Taghavi Mohammad ali Dehnavi ali Ghafouri Department of Chemical Engineering Imam Hossein Comprehensive University

Combustion chamber modeling and simulation of the liquid propellant engine with kerosene as fuel and liquid oxygen as an oxidizer in the turbulent flow field are performed by CFD *** flow is modeled as Single-phase in steady state and using RNG k-ε turbulence *** results are validated by experimental data of thrust,special impulse and combustion chamber *** comparing t.^wo reaction models of finite rate chemistry and frozen model with experimental data,it is concluded that finite rate chemistry has acceptable *** optimum value of equivalence ratio(oxidizer to fuel ratio)per reaction and operational parameters of the engine which maximize thrust and special impulse are determined.

关键词： Liquid propellant engine Computational fluid dynamics(CFD) Kerosene and oxygen Freeze model Finite rate chemistry model

Design feasibility of gamma camera without collimator based on specific arrangement of the detectors

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Nuclear Science and Techniques 2016年第4期27卷 120-126页

作者： Hossein Akbari-Lalimi seyed ali Shafiei Geriatric Care Research Center Rafsanjan University of Medical Sciences Department of Medical Physics Mashhad University of Medical Sciences Department of Physiology and Pharmacology School of Medicine Qom University of Medical Sciences

In gamma camera and single-photon emission computerized tomography, the collimator removes most photons. Here, a gamma camera without collimator utilizes a specific arrangement of detectors. Instead of bending beams(like a lens) or directing beams(by parallel hole collimator), changes are created in detectors' field of view(FOV), so that each detector's FOV looks different from others. Simulation proved this theory, with 98 detectors(2 cm 9 1.41 cm) arranged in a zigzag manner for Monte Carlo simulation. A radioactive source with energy of140 ke V was situated on the detectors' faces. Sixty projections, each 3(0 –179) apart, were simulated by Monte Carlo N-Particle(MCNP) 4C code, rotating detectors around a radioactive point. The band containing the radioactive source is clearly visible in each *** obtained after simulation in different projections were reconstructed, and point source location emerged correctly. Simulation of gamma camera with zigzag arrangement of detectors and MCNP-4C code demonstrated that one could string the space and determine radioactive source by image reconstruction without using collimators, solely through these special detectors' distribution.

关键词：探测器准直器 γ相机蒙特卡洛模拟计算机断层扫描单光子发射设计布置

Creep rupture assessment for Level-2 PSA of a 2-loop PWR： accounting for phenomenological uncertainties

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Nuclear Science and Techniques 2017年第8期28卷 117-125页

作者： Faramarz Yousefpour seyed Mohsen Hoseyni seyed Mojtaba Hoseyni seyed ali Hashemi Olia Kaveh Karimi Nuclear Science and Technology Research Institute TehranIran Young Researchers and Elite Club East Tehran BranchIslamic Azad University Tehran Iran

The Level-2 probabilistic safety assessment(PSA) of pressurized water reactors studies the possibility of creep rupture for major reactor coolant system components during the course of high pressure severe accident sequences. The present paper covers this technical issue and tries to quantify its associated phenomenological uncertainties for the development of Level-2 PSA. A framework is proposed for the formal quantification of uncertainties in the Level-2 PSA model of a PWR type nuclear power plant using an integrated deterministic and PSA approach. This is demonstrated for estimation of creep rupture failure probability in station blackout severe accident of a 2-loop PWR, which is the representative case for high pressure sequences. MELCOR 1.8.6 code is employed here as the deterministic tool for the assessment of physical phenomena in the course of accident. In addition, a MATLAB code is developed for quantification of the probabilistic part by treating the uncertainties through separation of aleatory and epistemic sources of *** probability for steam generator tube creep rupture is estimated at 0.17.

关键词：模型不确定性蠕变断裂 PSA 压水堆断裂评价二级现象学反应堆冷却剂系统

Human microbiome and prostate cancer development:current insights into the prevention and treatment

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Frontiers of Medicine 2021年第1期15卷 11-32页

作者： Solmaz Ohadian Moghadam seyed ali Momeni Uro-Oncology Research Center Tehran University of Medical SciencesTehranIran

The huge communities of microorganisms that symbiotically colonize humans are recognized as significant players in health and *** human microbiome may influence prostate cancer *** date,several studies have focused on the effect of prostate infections as well as the composition of the human microbiome in relation to prostate cancer *** studies suggest that the microbiota of men with prostate cancer significantly differs from that of healthy men,demonstrating that certain bacteria could be associated with cancer development as well as altered responses to *** healthy individuals,the microbiome plays a crucial role in the maintenance of homeostasis of body *** may contribute to the emergence of health problems,including malignancy through affecting systemic immune responses and creating systemic inflammation,and changing serum hormone *** this review,we discuss recent data about how the microbes colonizing different parts of the human body including urinary tract,gastrointestinal tract,oral cavity,and skin might affect the risk of developing prostate ***,we discuss strategies to target the microbiome for risk assessment,prevention,and treatment of prostate cancer.

关键词： microbiome prostate cancer prevention treatment molecular pathological epidemiology(MPE) biomarker

Ce-promoted Mn/Na_2 WO_4/SiO_2 catalyst for oxidative coupling of methane at atmospheric pressure

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Journal of Natural Gas Chemistry 2010年第1期19卷 47-53页

作者： seyed Mehdi Kamali Shahri ali Nakhaei Pour Research Institute of Petroleum Industry (RIPI) National Iranian Oil Company P. O. Box 18745-4163 Tehran Iran

A series of Ce-promoted Mn-Na2WO4/SiO2 catalysts were prepared by incipient wetness impregnation method, and their catalytic performance for oxidative coupling of methane （OCM） was investigated at atmospheric pressure in a micro-quartz-tube reactor. The catalysts were characterized by X-ray diffraction （XRD）, temperature program reduction （TPR） and BET surface area. Ce promoter increased surface area and Na2WO4 species dispersion, which enriched the amount of the surface species. In addition, Ce promoter increased the Na/W species reduction, but the reduction peak shifted to higher temperature. Stability test of 5wt%Ce catalyst indicated suitable performance and stability. The selectivity and yield of C^2＋ hydrocarbons after 50 h operation reached 65.5% and 19.6%, respectively, at 840 ℃ over 5wt%Ce-2wt%Mn5wt%Na2WO4/SiO2 catalyst.

关键词： oxidative coupling of methane CeO2 promoter Mn/Na2WO4/SiO2