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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 rise.On the other hand,investigating geopolymers as environmentally friendly binders to mitigate the greenhouse effect using soil stabilization has been widely conducted.However,the effect of CO_(2)exposure on the mechanical properties of geopolymer-stabilized soils is rarely reported.In this context,the effect of CO_(2)exposure on the mechanical and microstructural features of sandy soil stabilized with volcanic ash-based geopolymer was investigated.Several factors were concerned,for example the binder content,relative density,CO_(2)pressure,curing condition,curing time,and carbonate content.The results showed that the compressive strength of the stabilized sandy soil specimens with 20%volcanic ash increased from 3 MPa to 11 MPa.It was also observed that 100 kPa CO_(2)pressure was the optimal pressure for strength development among the other pressures.The mechanical strength showed a direct relationship with binder content and carbonate content.Additionally,in the ambient curing(AC)condition,the mechanical strength and carbonate content increased with the curing time.However,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 samples.Moreover,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 parameters.Methods:A systematic literature search was conducted to identify relevant studies investigating the association between SO2 exposure and semen quality parameters.This search encompassed the timeframe from January 2000 to May 2023 and included electronic databases such as Web of Science,Google Scholar,PubMed,Cochrane,and Scopus.Pooled 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 samples.Results:The results revealed a significant negative association between ambient SO2 exposure and certain semen quality parameters.In 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 parameters.Conclusions: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

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 pressure.One of the methods used in their repairs is the use of layered composites.The composite used must have the necessary strength.Therefore,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 B31.G.In addition,the experimental tests are replicated numerically using the finite element method.Setting the strain gauges at different distances from the defect location,can reduce the nonlinear effects,deformation,and fluctuations due to the high pressure.The direct relationship between the depth of an axial defect and the stress concentration is observed at the inner side edges of the defect.Composite 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

Correlation between critical thinking and emotional intelligence:a national crosssectional study on operating room nursing students in Iran

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Frontiers of Nursing 2024年第1期11卷 99-104页

作者： Armin Fereidouni Esmaeil Teymoori Tayebeh Bahmani hamid reza Sabet Zahra Maleki Mina Gharibi Department of Operating Room Technology Community Based Psychiatric Care Research CenterSchool of Nursing and MidwiferyShiraz University of Medical SciencesShirazIran Department of Operating Room Technology School of Paramedical SciencesAJA University of Medical SciencesTehranIran Department of Operating Room School of Allied Medical ScienceFasa University of Medical SciencesFasaIran Clinical Education Research Center Shiraz University of Medical SciencesShirazIran Medical Journalism Department School of Paramedical SciencesShiraz University of Medical SciencesShirazIran Department of Epidemiology Student Research CommitteeShiraz University of Medical SciencesShirazIran

Objective:According to the World Federation of Medical Education,critical thinking should be part of the training of medical and paramedical students.Professionals can improve the quality of care of patients after surgery by having or acquiring this skill in health care.Also,Emotional intelligence is introduced as an impor tant and effective factor on the professional performance and mental health of healthcare professionals.Thus,the present study was designed and implemented to determine the relationship between emotional intelligence and critical thinking among operating room nursing students of medical sciences universities in Iran.Methods:This cross-sectional study was done on 420 operating room students in 10 top medical sciences universities of Iran in 2022.The sampling method in this research was multistage sampling.The data collection instruments included demographic characteristics,Rickett's critical thinking,and Bradberry-Greaves'emotional intelligence questionnaires.After receiving the ethics code,data collection was done for 2 months.For data analysis,descriptive and inferential analyses including independent t-tests,analysis of variance,and Pearson correlation were used.The collected data were analyzed by SPSS 18(IBM Corporation,Armonk,New York,United States).P-value<0.05 was considered significant.Results:The mean age of the students participating in this study was 23.02±3.70 years,with women constituting 67.4%of them.The results of data analysis indicated that the mean total score of critical thinking and emotional intelligence was 124.10±37.52 and 114.12±43.63,respectively.A direct significant correlation between critical thinking and emotional intelligence(r=0.459,P-value<0.001)and a significant relationship between gender and emotional intelligence(P-value=0.028)were found.Conclusions:Based on the present study results,educational managers in the Ministry of Health are suggested to consider suitable educational programs for improving critical thinking and emotional intelligence to enhance the qu

关键词： critical thinking emotional intelligence operating room students operating room nurses

Molecular investigation of exoU and exoY virulence genes in Pseudomonas aeruginosa collected from hospitalized patients in North of Iran:A descriptive-analytical study

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Journal of Acute Disease 2024年第2期13卷 74-80页

作者： Ahmad reza Moradi Mehrdad Gholami Lotfollah Davoodi Negar Hajilou hamid reza Goli Sana Institute of Higher Education SariIran Department of Medical Microbiology and Virology Faculty of MedicineMazandaran University of Medical SciencesSariIran Antimicrobial Resistance Research Center Faculty of MedicineMazandaran University of Medical SciencesSariIran Molecular and Cell Biology Research Center Faculty of MedicineMazandaran University of Medical SciencesSariIran

Objective:To investigate the frequency of exoU and exoY genes in patients with Pseudomonas aeruginosa infection.Methods:In this study,100 clinical isolates of Pseudomonas aeruginosa were collected from patients hospitalized in educational-therapeutic hospitals and were identified using standard microbiological tests.Then,the antibiotic resistance pattern of the isolates was determined by the disk agar diffusion method.The bacterial DNAs were extracted by the alkaline lysis method.Finally,the presence of exoU and exoY genes was evaluated by the PCR test.Results:In this study,47%,72%,29%,39%,40%,and 44%of the isolates were non-susceptible to piperacillin,aztreonam,ceftazidime,imipenem,tobramycin,and ciprofloxacin,respectively.In addition,95%and 93%of the clinical isolates carried the exoU and exoY genes.Blood and fecal isolates had both virulence genes,while only one wound isolate had neither genes.Meanwhile,all urinary isolates contained the exoY gene and only one isolate lacked the exoU gene.Also,88 isolates simultaneously had both exoU and exoY genes.Conclusions:High prevalence of exoU and exoY genes in this region indicates a significant role of typeⅢsecretion system in pathogenesis of Pseudomonas aeruginosa.The typeⅢsecretion system may be a suitable target to reduce the pathogenicity of this bacterium.

关键词： Pseudomonas aeruginosa exoU exoY Virulence gene TypeⅢsecretion system PCR

Phylogeography,genetic variability and structure of Acanthamoeba metapopulations in Iran inferred by 18S ribosomal RNA sequences:A systematic review and meta-analysis

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Asian Pacific Journal of Tropical Medicine 2017年第9期10卷 855-863页

作者： Adel Spotin Hamid Reza Moslemzadeh Mahmoud Mahami-Oskouei Ehsan Ahmadpour Maryam Niyyati Seyed Hossein Hejazi Fatemeh Memari Jafar Noori Immunology Research Center Tabriz University of Medical SciencesTabrizIran Department of Parasitology and Mycology Faculty of MedicineTabriz University of Medical SciencesTabrizIran Department of Medical Parasitology and Mycology School of MedicineShahid Beheshti University of Medical SciencesTehranIran Department of Parasitology and Mycology School of MedicineIsfahan University of Medical SciencesIsfahanIran

Objective: To verify phylogeography and genetic structure of Acanthamoeba populations among the Iranian clinical isolates and natural/artificial environments distributed in various regions of the country.Methods: We searched electronic databases including Medline, Pub Med, Science Direct, Scopus and Google Scholar from 2005 to 2016. To explore the genetic variability of Acanthamoeba sp, 205 sequences were retrieved from keratitis patients, immunosuppressed cases and environmental sources as of various geographies of Iran.Results: T4 genotype was the predominant strain in Iran, and the rare genotypes belonged to T2, T3, T5(Acanthamoeba lenticulata), T6, T9, T11, T13 and T15(Acanthamoeba jacobsi).A total of 47 unique haplotypes of T4 were identified. A parsimonious network of the sequence haplotypes demonstrated star-like feature containing haplogroups IR6(34.1%) and IR7(31.2%) as the most common haplotypes. In accordance with the analysis of molecular variance, the high value of haplotype diversity(0.612–0.848) of Acanthamoeba T4 represented genetic variability within populations. Neutrality indices of the 18 S ribosomal RNA demonstrated negative values in all populations which represented a considerable divergence from neutrality. The majority of genetic diversity belonged to the infected contact lens and dust samples in immunodeficiency and ophthalmology wards, which indicated potential routes for exposure to a pathogenic Acanthamoeba sp. in at-risk individuals. A pairwise fixation index(FST) was from low to high values(0.024 33–0.418 92). The statistically FST points out that T4 is genetically differentiated between north-west, north-south and centralsouth metapopulations, but not differentiated between west-central, west-south, centralsouth, and north-central isolates.Conclusions: An occurrence of IR6 and IR7 displays that possibly a gene flow of Acanthamoeba T4 occurred after the founder effect or bottleneck experience through ecological changes or host mobility. This is the first systematic review and meta-a

关键词： Acanthamoeba metapopulations 基因可变性基因流动分子的发展史伊朗

脆性材料I型(张开)-断裂韧性测定的PFC2D和试验研究:一种新方法

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Acta Mechanica Sinica 2024年第2期40卷 116-130页

作者：付金伟 Hadi Haeri Joseph FLabuz Vahab Sarfarazi Pouyan Ebneabbasi MRM Aliha hamid reza Karimi Shirin Jahanmiri Mohammad Fatehi Marji School of Civil Engineering and Transportation North China University of Water Resources and Electric PowerZhengzhou450046China Department of Mining Engineering Higher Education Complex of ZarandShahid Bahonar University of KermanKermanIran Department of Civil Environmentaland Geo-EngineeringUniversity of MinnesotaMinneapolis55455USA Department of Mining Engineering Hamedan University of TechnologyHamedanIran Research Scholar Civil Engineering DepartmentIslamic Azad UniversityHamedanIran Welding and Joining Research Center School of Industrial EngineeringIran University of Science and TechnologyNarmakTehranIran School of Civil Engineering Iran University of Science and Technology(IUST)NarmakTehranIran Department of Mine Exploitation Engineering Faculty of Mining and MetallurgyInstitute of EngineeringYazd UniversityYazdIran

在本文研究中,通过利用优势边缘缺口盘型(END)试样,确定了石灰石的断裂韧性,提出了一种新的石灰石归一化相应力、高相变的计算方法.采用柔性有限元法(FEM)对试样的I型(张开)-断裂韧性进行了精确计算,并得到了相应实用公式.在试验中,还... 详细信息

在本文研究中,通过利用优势边缘缺口盘型(END)试样,确定了石灰石的断裂韧性,提出了一种新的石灰石归一化相应力、高相变的计算方法.采用柔性有限元法(FEM)对试样的I型(张开)-断裂韧性进行了精确计算,并得到了相应实用公式.在试验中,还使用含缺口巴西圆盘(NBD)试件,测试了END程序的准确性.为了在数值上重现这些测试并验证断裂韧性测量的正确性,还对END测试进行了离散元分析.数值模拟结果与实验结果吻合良好.然而,END研究所确定的韧性水平低于NBD测试规定的韧性水平,这是因为END石灰石样品中的缺口具有均匀的拉伸应力分布.

关键词：断裂韧性脆性材料实用公式拉伸应力巴西圆盘离散元分析相变归一化

Solubility study and selective purification of HMX explosive in organic electrolyte solution of zinc acetate/diethylene glycol

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Defence Technology(防务技术) 2023年第11期29卷 15-23页

作者： Javad Ghorbani Sajjad Damiri hamid reza Pouretedal Faculty of Applied Sciences Maleke-ashtar University of TechnologyP.O.Box83145/115Iran

In this study, an organic electrolyte solution based on zinc acetate/diethylene glycol(ZA/DEG) is introduced for the selective purification of cyclotetramethylene tetranitramine(HMX) high explosive from its identical homologue cyclotrimethylene trinitramine(RDX). The dielectric constant of various organic solutions were investigated through Electrochemical Impedance Spectroscopy(EIS) in the range of 1.0 Hz—30 MHz. and some quantum-chemical descriptors of RDX and HMX dissolutions in the ZA cosolvent were analyzed using Density Functional Theory(DFT). The results show dielectric constant and solubility of RDX is higher than that of HMX, and by increasing of ZA concentration in DEG solvent, the values of dielectric constants were enhanced. Furthermore, the presence of ZA cosolvent on the solubility of two explosives was statistically investigated by Central Composite Design(CCD) of experiment, and some solubility parameters including activity coefficient, dissolving enthalpy, and mixing enthalpies were determined. The experimental results indicate that the weight ratio of RDX to HMX solubility in the proposed organic electrolyte changes up to 30 times, which provides a selective and sequential separation method to separate two materials with similar chemical properties with a separation efficiency>98% and HMX purity> 99.8%. The X-Ray Diffraction(XRD) analysis, High-Performance Liquid Chromatography(HPLC), Laser-Induced Breakdown Spectroscopy(LIBS), and Fourier Transform Infrared Spectroscopy(FT-IR) approves the acceptable quality of the separated materials. The proposed method makes the efficient and safe purification of high-quality HMX for application in oil and gas well perforating gun charges, using a nonvolatile and inflammable organic electrolyte.

关键词： Organic electrolyte Purification Solubility HMX RDX Diethylene glycol

Fault ride-through capability improvement in a DFIG-based wind turbine using modified ADRC

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Protection and Control of Modern Power Systems 2022年第1期7卷 751-787页

作者： Seyed reza Mosayyebi Seyed hamid Shahalami Hamed Mojallali Electrical Engineering Department Faculty of EngineeringUniversity of GuilanRashtIran

In this paper,an overview of several strategies for fault ride-through(FRT)capability improvement of a doubly-fed induction generator(DFIG)-based wind turbine is presented.Uncertainties and parameter variations have adverse effects on the performance of these strategies.It is desirable to use a control method that is robust to such distur-bances.Auto disturbance rejection control(ADRC)is one of the most common methods for eliminating the effects of disturbances.To improve the performance of the conventional ADRC,a modified ADRC is introduced that is more robust to disturbances and offers better responses.The non-derivability of the fal function used in the conventional ADRC degrades its efficiency,so the modified ADRC uses alternative functions that are derivable at all points,i.e.,the odd trigonometric and hyperbolic functions(arcsinh,arctan,and tanh).To improve the effciency of the proposed ADRC,fuzzy logic and fractional-order functions are used simultaneously.In fuzzy fractional-order ADRC(FFOADRC),all disturbances are evaluated using a nonlinear fractional-order extended state observer(NFESO).The performance of the suggested structure is investigated in MATLAB/Simulink.The simulation results show that during disturbances such as network voltage sag/swell,using the modified ADRCs leads to smaller fluctuations in stator flux amplitude and DC-link voltage,lower variations in DFIG velocity,and lower total harmonic distortion(THD)of the stator current.This demonstrates the superiority over conventional ADRC and a proportional-integral(PI)controller.Also,by chang-ing the crowbar resistance and using the modified ADRCs,the peak values of the waveforms(torque and currents)can be controlled at the moment of fault occurrence with no significant distortion.

关键词： Doubly-fed induction generator(DFIG) Auto disturbance rejection control(ADRC) Fault ride-through(FRT) Wind turbine Nonlinear fractional-order extended state observer(NFESO)