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Characteristics of turbulent flow in 3-D pools in the presence of submerged rigid vegetation in channel bed

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Journal of Hydrodynamics 2024年第1期36卷 158-169页

作者： Kourosh Nosrati Hossein Afzalimehr Jueyi Sui hamid reza Reisifar Natural Disasters Prevention Research Center Faculty of Civil EngineeringIran University of Science and TechnologyTehranIran School of Engineering University of Northern British ColumbiaPrince GeorgeCanada

In this study,the interaction between 3-D bedforms and submerged rigid vegetation has been *** laboratory experiments were conducted to study the distribution of flow velocity,Reynolds shear stress,turbulent kinetic energy,and skewness coefficients for a constant density of *** showed that the velocity profile in the pool section deviates from those in the upstream section of the *** has been found that the dip parameter varied between 0.6H and 0.9H depending on various factors including bed roughness,vegetation distribution,and pool entrance/exit ***,scattered vegetation in the pool and differences in slopes created non-uniform flow ***,in the wake region behind each vegetated element,flow velocity reduced significantly,and small-scale eddies are formed,causing increased *** decreasing the entrance slope and bed roughness,relatively uniform flow and weaker turbulence was resulted,but the random distribution of vegetated elements counteracted this balance and intensified *** the decrease in the pool entrance slope,the contribution of sweep event decreased and the contribution of ejection event increased.

关键词： Submerged rigid vegetation 3-D pool Reynolds shear stress skewness coefficients

Applying Indexing Method to Gas Pipeline Risk Assessment by Using GIS: A Case Study in Savadkooh, North of Iran

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Journal of Environmental Protection 2011年第7期2卷 947-955页

作者： hamid reza jafari Saeed Karimi Gholamreza Nabi Bidhendi Mousa Jabari Nasim Kheirkhah Ghahi 不详

Gas pipelines are environmentally sensitive because they cross varied fields, rivers, forests, populated areas, desert, hills and offshore and also different parameters in gas transmission progresses are effective. Underground gas transmission pipelines have been grown as one of the low risk methods with low cost in the world specially in middle east and Europe. Physical and chemical properties of liquid gas, pipeline properties and also its environmental condition are the main factors of increasing the technical and environmental risk. In this article the quantitative risk assessment has been done by using GIS and overlaying the information layers. For this purpose, all effective risk factors were identified and projected. In order to achieve the same and comparable results, the entire pipeline route was divided into 500 meter intervals and the risk was calculated in each interval, finally the scores of these intervals such as each criterion risk was calculated. The case study of the article is Savadkooh to PoleSefid pipeline in Mazandaran.

关键词： Risk Assessment Pipeline GIS Environment

Effects of heat stress and long photoperiod on the prostate of rats

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Asian pacific Journal of Reproduction 2024年第4期13卷 187-196页

作者： hamid reza Ghaffari Javad Poursamimi Department of Basic Sciences School of MedicineZabol University of Medical SciencesZabolIran Department of Immunology Faculty of MedicineZabol University of Medical SciencesZabolIran

Objective:To examine light and heat effects on the morphological,histological,and micrometric structure of the prostate of ***:Thirty adult male rats were divided into three *** control group was kept under 20℃-22℃ and an artificial 12 h/12 h day/night cycle;the temperature group was under normal light and at(42±1)℃ heat for 4 to 5 h daily,and the light group was exposed to 8 h/16 h day/night cycle with 20℃-22℃.Rats were weighed five times(at the beginning of the study and every seven days).Five milliliters(mL)of their peripheral blood were *** tissue staining was performed using the hematoxylin-eosin(H&E)stain and periodic acid-Schiff(PAS).In the following,tissue and cellular reactions to the PAS were ***:Folds were located entirely on the surface of the anterior lobe and periphery of the other *** secretory units in the anterior lobe were more than the lateral lobe.A strong reaction of the secretory cells to the PAS was *** serum levels of the light group also significantly increased compared to the control group(P<0.05).The most histometric changes of the lobes were established in the lateral *** stress resulted in a significant decrease in testosterone levels and transformed prostate *** epithelium and parenchyma to scaffold ratio in the temperature group ***:Maximum and minimum changes in the ventral lobe happened under the ascent of temperature and light,*** ventral lobe in the study of prostatic hyperplasia should be more considered.

关键词： Prostate Heat stress Photoperiod Histology Testosterone Rat

Evaluating the characteristics of geological structures in karst groundwater inflow, Nowsud Tunnel

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Journal of Mountain Science 2024年第10期21卷 3434-3452页

作者： BAYAT Narges SADEGHI Erfan NASSERY hamid reza Department of Minerals and Groundwater Resources Faculty of Earth SciencesShahid Beheshti UniversityEvin AveTehran ***Iran Ministry of Energy Kordestan ExpyTehran ***Iran

Highly permeable geological structures such as dissolution channels, open fractures, and faults create environmental challenges regard to hydrological and hydrogeological aspects of underground construction, often causing significant groundwater inflow during drilling due to the limitations of empirical and analytical methods. This study aims to identify the geological factors influencing water flow into the tunnel. High-flow zones' geological features have been identified and examined for this purpose. According to the geological complexity of the Nowsud tunnel, presence of different formations with different permeability and karstification have led to a high volume of underground inflow water (up to 4700 L/s) to the tunnel. The Nowsud tunnel faces significant geological and hydrogeological challenges due to its passage through the Ilam formation's LI2 unit, characterized by dissolution channels, faults, and fractures. The highest inflow rate (4700 L/s) occurred in the Hz-9 zone within the Zimkan anticline. The relationship between geological features and groundwater inflow indicates that anticlines are more susceptible to inflow than synclines. Additionally, different types of faults exhibit varying hydraulic effects, with strike-slip faults having the most significant impact on groundwater inflow, thrust faults conducting less water into the tunnel, and inflow through normal faults being negligible compared to the other two types of faults. The novelty of this paper lies in its detailed analysis of geological features influencing groundwater inflow into the Nowsud tunnel, providing empirical data on high-flow zones and differentiating the hydraulic effects of various fault types, which enhances the understanding and prediction of groundwater inflow in underground constructions.

关键词： Geological structures Groundwater inflow Hydrogeology Nowsud tunnel Karst

Effect of CO_(2)exposure on the mechanical strength of geopolymerstabilized sandy soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 670-681页

作者： hamid reza Razeghi Armin Geranghadr Fatemeh Safaee Pooria Ghadir Akbar A.Javadi School of Civil Engineering Iran University of Science and TechnologyTehran***Iran Department of Engineering University of ExeterExeterEX44QFUK

In recent years,there has been growing interest in developing methods for mitigating greenhouse effect,as greenhouse gas emissions continue to contribute to global temperature *** the other hand,investigating geopolymers as environmentally friendly binders to mitigate the greenhouse effect using soil stabilization has been widely ***,the effect of CO_(2)exposure on the mechanical properties of geopolymer-stabilized soils is rarely *** this context,the effect of CO_(2)exposure on the mechanical and microstructural features of sandy soil stabilized with volcanic ash-based geopolymer was *** factors were concerned,for example the binder content,relative density,CO_(2)pressure,curing condition,curing time,and carbonate *** results showed that the compressive strength of the stabilized sandy soil specimens with 20%volcanic ash increased from 3 MPa to 11 *** was also observed that 100 kPa CO_(2)pressure was the optimal pressure for strength development among the other *** mechanical strength showed a direct relationship with binder content and carbonate ***,in the ambient curing(AC)condition,the mechanical strength and carbonate content increased with the curing ***,the required water for carbonation evaporated after 7 d of oven curing(OC)condition and as a result,the 14-d cured samples showed lower mechanical strength and carbonate content in comparison with 7-d cured ***,the rate of strength development was higher in OC cured samples than AC cured samples until 7 d due to higher geopolymerization and carbonation rate.

关键词： Soil stabilization CO_(2)effect Geopolymer

Exploring the relationship between ambient sulfur dioxide and semen quality parameters:A systematic review and meta-analysis

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Asian pacific Journal of Reproduction 2024年第1期13卷 12-21页

作者： Seyed Sobhan Bahreiny Mojtaba Aghaei Mohammad reza Dabbagh hamid Ghorbani Moslem Javidan reza Mohammadpour Fard Student Research Committee Ahvaz Jundishapur University of Medical SciencesAhvazIran Medical Basic Sciences Research Institute Physiology Research CenterDepartment of PhysiologySchool of MedicineAhvaz Jundishapur University of Medical SciencesAhvazIran Department of Biology Faculty of ScienceShahid Chamran University of AhvazAhvazIran Department of Immunology Faculty of MedicineAhvaz Jundishapur University of Medical SciencesAhvazIran

Objective:To investigate the relationship between ambient sulfur dioxide(SO2)exposure and semen quality ***:A systematic literature search was conducted to identify relevant studies investigating the association between SO2 exposure and semen quality *** search encompassed the timeframe from January 2000 to May 2023 and included electronic databases such as Web of Science,Google Scholar,PubMed,Cochrane,and *** effect estimates with 95%confidence intervals(CI)were calculated using percent changes(PC).The meta-analysis included seven studies with 6711 participants and 15087 semen ***:The results revealed a significant negative association between ambient SO2 exposure and certain semen quality *** particular,SO2 exposure was associated with a significant decrease in progressive motility(PC=0.032;95%CI:-0.063 to-0.001;P=0.044)and sperm concentration(PC=-0.020;95%CI:-0.036 to-0.005;P=0.012).However,no statistically significant associations were observed for total sperm count(PC=-0.038;95%CI:-0.079 to 0.003;P=0.070),seminal fluid volume(PC=-0.009;95%CI:-0.048 to-0.030;P=0.662)and sperm motility(PC=-0.17;95%CI:-0.363 to 0.022;P=0.830).In addition,the results of the subgroup analysis revealed specific variables that were associated with the decrease in relevant sperm ***:This systematic review and meta-analysis provides compelling evidence supporting a consistent negative association between exposure to ambient SO2 and semen quality parameters.

关键词： Semen quality Sulfur dioxide Ambient air pollution Meta-analysis

Chemically Modified Sugarcane Bagasse for Innovative Bio-Composites. Part One: Production and Physico-Mechanical Properties

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Journal of Renewable Materials 2024年第10期12卷 1715-1728页

作者： Peyman Ahmadi Davood Efhamisisi Marie-France Thévenon hamid Zarea Hosseinabadi reza Oladi Jean Gerard Department of Wood and Paper Science and Technology Faculty of Natural ResourcesUniversity College of Agriculture and Natural ResourcesUniversity of TehranKaraj***Iran CIRAD UPR BioWooEBMontpellierF-34398France BioWooEB University of MontpellierCIRADMontpellierF-34398France

Sugarcane bagasse is an agro-waste that could replace timber resources for the production of *** boards such as particleboard offer an issue for the use and recycling of poor quality timber,and these engineered products can overcome some solid wood limitations such as heterogeneity and *** offers an alternative to wood chips for particleboard production but present some disadvantages as well,such as poor physico-mechanical *** address these issues,bagasseﬁbers were treated with an innovative natural resin formulated with tannin and *** particles with different concentrations of resin(5%,10%,and 15%m/m)were exposed to temperatures of 40°C,60°C,80°C,and 100°C for resin *** types of tannin-based adhesives,including tannin formaldehyde,tannin/formaldehyde-furfural,and tannin hex-amine,were utilized for bonding the treated bagasse *** resultant panels were assessed for their physical and mechanical properties and compared to those produced using Melamine-Urea-Formaldehyde(MUF)*** density of the panels varied from 650 to 730 kg/m3 depending on the resin *** values for both modulus of elasticity and modulus of rupture increased as the resin concentration *** internal bonding values exhibited an increase with resin concentration up to a critical point,after which a decreasing trend was *** water absorption and thickness swelling were signiﬁcantly reduced with an increase in resin ***,the panels produced using MUF adhesive yielded the most favorable physico-mechanical ***,the panels made with tannin-based adhesives met the minimum requirements speciﬁed in the standard EN 312(speciﬁcations for uncoated resin-bonded particleboards)for application in dry *** analysis of formaldehyde emissions indicated that panels produced with tannin-based adhesives exhib-ited signiﬁcantly lower emissions compared to tho

关键词： Sugarcane bagasse particleboard tannin furfural physico-mechanical properties formaldehyde

Hepatoprotective effect of Holothuria leucospilota methanolic extract on dimethyl nitrosamine-induced hepatotoxicity in rats

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Animal Models and Experimental Medicine 2024年第4期7卷 544-552页

作者： Fatemeh Dejan Amineh Daneshi Javad Rajabi Aslani Nasrollah Ahmadi Narges Eskandari Roozbahani Elaham Rahmanian reza Behmanesh hamid reza Gheisari Department of Basic Sciences School of Veterinary MedicineShiraz UniversityShirazIran Department of Education Farzanegan High SchoolTehranKohgiluyeh and Boyer AhmadIran Food Hygiene Department School of Veterinary MedicineShiraz UniversityShirazIran Department of Pathology School of Veterinary MedicineShiraz UniversityShirazIran Clinical Research Development Center Imam Reza HospitalKermanshah University of Medical SciencesKermanshahIran Molecular Dermatology Research Center Shiraz University of Medical SciencesShirazIran Department of Anatomy School of MedicineShiraz University of Medical SciencesShirazIran Faculty of Veterinary Medicine Garmsar BranchDepartment of RadiologyIslamic Azad UniversityGarmsarIran

Background:Complementary medicine is an interesting field for extracting bio-active compounds from various plant and animal *** hepatoprotective effect of the methanolic extract of a species of sea cucumber called Holothuria leu-cospilota in an animal model of liver cancer caused by dimethyl nitrosamine(DMN)was ***:Wistar female rats were randomly divided into five groups(n=12):control(intact),positive control(received 1%DMN[10 mg/kg/week,intraperitoneally]for 12 weeks),and three treatment groups(received 50,100,and 200 mg/kg/day ***-cospilota extract orally for 12 weeks along with intraperitoneal administration of 1%DMN[10 mg/kg/week]).In all groups,ultrasound was performed on the liver every week to check its *** sampling and liver isolation were performed on three occasions,at 4,8,and 12 weeks,to check liver enzymes and the histopathological condition of the liver tissue(every week,four animals from each group were randomly selected).Results:Liver density changes were evident from the eighth week onward in the positive control *** results indicated pathologic changes in the positive control group after 4 *** increase in liver enzymes in the posi-tive control group was significantly different from that in the treatment and control ***:We demonstrated the hepatoprotective effect of *** on DMN-induced liver damage in rats using biochemical and histological parameters and *** additional research(in silico or in vitro)is needed to find the exact mechanism and the main biological compound in ***.

关键词： dimethyl nitrosamine hepatotoxicity Holothuria leucospilota sea cucumber

Experimental and Finite Element Analysis of Corroded High-Pressure Pipeline Repaired by Laminated Composite

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1783-1806页

作者： Seyed Mohammad reza Abtahi Saeid Ansari Sadrabadi Gholam Hosein Rahimi Gaurav Singh hamid Abyar Daniele Amato Luigi Federico Faculty of Mechanical Engineering Tarbiat Modares UniversityTehran***Iran A.Leon Linton Department of Mechanical Robotics and Industrial EngineeringLawrence Technological UniversitySouthfieldMI48075USA Department of Mechanical Engineering Faculty of EngineeringMeybod UniversityYazd***Iran Department of Industrial Engineering University of SalernoVia Giovanni PaoloⅡFiscianoItaly Italian Aerospace Research Center(C.I.R.A.) Via MaioriseCapuaCE81043Italy

Repairs of corroded high-pressure pipelines are essential for fluids transportation under high *** of the methods used in their repairs is the use of layered *** composite used must have the necessary ***,the experiments and analytical solutions presented in this paper are performed according to the relevant standards and codes,including ASME PCC-2,ASME B31.8S,ASME B31.4,ISO 24817 and ASME *** addition,the experimental tests are replicated numerically using the finite element *** the strain gauges at different distances from the defect location,can reduce the nonlinear effects,deformation,and fluctuations due to the high *** direct relationship between the depth of an axial defect and the stress concentration is observed at the inner side edges of the *** reparation reduces the non-linearities related to the sharp variation of the geometry and a more reliable numerical simulation could be performed.

关键词： High-pressure pipeline composite repair ASME PCC-2 ISO 24817