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Delamination analysis of woven fabrication laminates using cohesive zone model

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Journal of Central South University 2016年第1期23卷 27-38页

作者： Mohsen moslemi Mohammadreza Khoshravan azar Department of Mechanical Engineering University of Tabriz

A new test method was proposed to evaluate the cohesive strength of composite laminates. Cohesive strength and the critical strain energy for Mode-II interlamiar fracture of E-glass/epoxy woven fabrication were determined from the single lap joint(SLJ) and end notch flexure(ENF) test, respectively. In order to verify their adequacy, a cohesive zone model simulation based on interface finite elements was performed. A closed form solution for determination of the penalty stiffness parameter was proposed. Modified form of Park-Paulino-Roesler traction-separation law was provided and conducted altogether with trapezoidal and bilinear mixed-mode damage models to simulate damage using Abaqus cohesive elements. It was observed that accurate damage prediction and numerical convergence were obtained using the proposed penalty stiffness. Comparison between three damage models reveals that good simulation of fracture process zone and delamination prediction were obtained using the modified PPR model as damage model. Cohesive zone length as a material property was determined. To ensure the sufficient dissipation of energy, it was recommended that at least 4 elements should span cohesive zone length.

关键词： cohesive zone model delamination cohesive strength finite element prediction

Experimental investigation into effects of the natural polymer and nanoclay particles on the EOR performance of chemical flooding in carbonate reservoirs

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Petroleum Science 2024年第2期21卷 951-961页

作者： Amir Mohammad Zamani Ashkan moslemi Kamran Hassani Department of Petroleum Engineering Islamic Azad University Science and Research BranchTehranIran Institute of Petroleum Engineering University of TehranTehranIran

This paper aims to investigate the tragacanth gum potential as a natural polymer combined with natural clay mineral(montmorillonite,kaolinite,and illite)nanoparticles(NPs)to form NP-polymer suspension for enhanced oil recovery(EOR)in carbonate *** gravimetric analysis(TGA)tests were conducted initially in order to evaluate the properties of tragacanth ***,scanning electron microscopy(SEM)and energy-dispersive X-ray(EDX)tests were used to detect the structure of clay *** various scenarios,the effects of natural NPs and polymer on the wettability alteration,interfacial tension(IFT)reduction,viscosity improvement,and oil recovery were investigated through contact angle system,ring method,Anton Paar viscometer,and core flooding tests,*** entire experiment was conducted at 25,50,and 75℃,*** to the experimental results,the clay minerals alone did not have a significant effect on viscosity,but the addition of minerals to the polymer solution leads to the viscosity enhancement remarkably,resulting mobility ratio *** clay NPs,the combination of natural polymer and kaolinite results in increased viscosity at all *** wettability alteration was also observed in the case of natural polymer and illite *** in combination with natural polymer showed an ability in reducing ***,the results of displacement experiments revealed that the combination of natural polymer and kaolinite could be the best option for EOR due to its substantial ability to improve the recovery factor.

关键词： Chemical flooding Tragacanth gum Clay nanoparticle Wettability IFT

Experimental and numerical study of the blast wave decrease using sandwich panel by granular materials core

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Defence Technology（防务技术） 2021年第5期17卷 1660-1670页

作者： Masoud Rahmani Alireza Naddaf Oskouei Amin moslemi Petrudi Department of Mechanical Engineering IHU UniversityTehranIran Department of Mechanical Engineering Tehran UniversityTehranIran

Among the intrinsic properties of some materials,e.g.,foams,porous materials,and granular materials,are their ability to mitigate shock *** paper investigated shock wave mitigation by a sandwich panel with a granular *** simulations and experimental tests were performed using Autodyn hydro-code software and a shock tube,*** smoothed particle hydrodynamics(SPH)method was used to model granular *** and pumice,whose properties were determined by several compression tests,were used as granular materials in the sandwich panel *** granular materials possess many mechanisms,including compacting(e.g.,sawdust)and crushing(e.g.,pumice)that mitigate shock/blast *** results indicated the ineffectiveness of using a core with low thickness,yet it was demonstrated to be effective with high ***-thickness pumice yielded better results for wave *** use of these materials with a core with appropriate core reduces up to 88%of the shock *** results of the experiments and numerical simulations were compared,suggesting a good agreement between the *** indicates the accuracy of simulation and the ability of the SPH method to modeling granular material under shock *** effects of grain size and the coefficient of friction between grains have also been investigated using simulation,implying that increasing the grain size and coefficient of friction between grains both reduce overpressure.

关键词： Granular materials Shock tube Blast wave Numerical simulations

Experimental evaluation of blanking and piercing of PVC based composite and hybrid laminates

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Advances in Manufacturing 2016年第3期4卷 248-256页

作者： Vahid Zal Hassan moslemi Naeini Ahmad Reza Bahramian Behnam Abbaszadeh Faculty of Mechanical Engineering Tarbiat ModaresUniversity Tehran Iran Faculty of Chemical Engineering Tarbiat ModaresUniversity Tehran Iran

Blanking is one of the high speed processes to produce fiat products from sheets economically. In order to expand this process to new materials, the blanking of polyvinyl chloride （PVC）/fiberglass thermoplastic com- posite laminates and composite/aluminum hybrid laminates was investigated. The laminates were produced by the film stacking procedure and then blanked by circular die and punches. The blanking process was done in two levels of clearance including 4% and 8% of the laminates thickness, two levels of punch speed including 40 mm/min and 200 mm/min and at two levels of temperature （room tem- perature and 80 ℃） for both composite and hybrid laminates. The effects of the parameters on the maximum blanking force, cutting energy, and quality and precision of sheared edges were studied. Cutting mechanism for blanking in different conditions was explained. It was concluded that at room temperature, blanked composite and hybrid laminates had a high quality of sheared edges but at elevated temperature, although the maximum blanking force was reduced, the quality of sheared edge was reduced significantly.

关键词： Composite laminate Hybrid laminate Blanking Fiberglass Polyvinyl chloride (PVC)

EXPERIMENTAL AND THEORETICAL INVESTIGATION OF THE FIRST FOLD CREATION IN THIN WALLED COLUMNS

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Acta Mechanica Solida Sinica 2010年第4期23卷 353-360页

作者： Abbas Niknejad G.H.Liaghat H.moslemi Naeini A.H.Behravesh Mechanical Engineering Department Yasouj University Faculty of Engineering Payame Noor University (PNU) Mechanical Engineering Department Faculty of EngineeringTarbiat Modares University

In this paper, a theoretical formula is presented to predict the instantaneous folding force of the first fold creation in square and rectangular columns under axial *** rectangular column is a small and single model of honeycombs with square or rectangular *** are based on the analysis of the Basic Folding Mechanism （BFM）.For this purpose, sum of the dissipated energy rate under bending around horizontal and inclined hinge lines and the dissipated energy rate under extensional deformations was equal to the work rate of the external force on the *** final formula obtained in this research, reasonably predicts the instantaneous folding force of single-cell square and rectangular honeycombs instead of the average ***, according to the calculated theoretical relation, the instantaneous folding force of the first fold creation in a square column was sketched versus folding distance and compared to the experimental results, which showed a good correlation.

关键词： dissipated energy rate first fold creation instantaneous folding force thin walled column

Magnetic Field Effect and Heat Transfer of Nanofluids within Waveform Microchannel

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Computer Modeling in Engineering & Sciences 2023年第3期134卷 1957-1973页

作者： Mehdi moslemi Motahare Mahmoodnezhad S.A.Edalatpanah Sulima Ahmed Mohammed Zubair Hamiden Abd El-Wahed Khalifa Ayandegan Institute of Higher Education TonekabonIran Department of Mathematics College of Science and ArtsQassim UniversityAr RassSaudi Arabia Operations Research Department Faculty of Graduate Studies for Statistical ResearchCairo UniversityGizaEgypt

In this research,a numerical study of mixed convection of non-Newtonian fluid and magnetic field effect along a vertical wavy surface was investigated.A simple coordinate transformation to transform wavy surface to a flat surface is employed.A cubic spline collocation numerical method is employed to analyze transformed *** effect of various parameters such as Reynolds number,volume fraction 0-,Hartmann number,and amplitude of wave length was evaluated in improving the performance of a wavy *** to the presented results,the sinusoidal shape of the microchannel has a direct impact on heat *** increasing the microchannel wave amplitude,the Nusselt number has *** the other hand,increasing the heat transfer in the higher wavelength ratio corrugated channel is seen as an effective method of increasing the heat transfer,especially at higher Reynolds *** results showed that with increasing Hartmann numbers,the flow line near thewall becomesmore regular and,according to the temperature gradient created,theNusselt number growth.

关键词： Heat transfer magnetic field nano fluid vorticity wavy micro channel

Fractured reservoir history matching improved based on artificial intelligent

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Petroleum 2016年第4期2卷 344-360页

作者： Sayyed Hadi Riazi Ghasem Zargar Mehdi Baharimoghadam Bahman moslemi Ebrahim Sharifi Darani Department of Petroleum Engineering Petroleum University of Technology(PUT)AhwazIran Department of Reservoir Evaluation National Iranian South Oil Company(NISOC)AhwazIran

In this paper,a new robust approach based on Least Square Support Vector Machine(LSSVM)as a proxy model is used for an automatic fractured reservoir history *** proxy model is made to model the history match objective function(mismatch values)based on the history data of the *** model is then used to minimize the objective function through Particle Swarm Optimization(PSO)and Imperialist Competitive Algorithm(ICA).In automatic history matching,sensitive analysis is often performed on full simulation *** this work,to get new range of the uncertain parameters(matching parameters)in which the objective function has a minimum value,sensitivity analysis is also performed on the proxy *** applying the modified ranges to the optimization methods,optimization of the objective function will be faster and outputs of the optimization methods(matching parameters)are produced in less time and with high *** procedure leads to matching of history of the field in which a set of reservoir parameters is *** final sets of parameters are then applied for the full simulation model to validate the *** obtained results show that the present procedure in this work is effective for history matching process due to its robust dependability and fast convergence *** to high speed and need for small data sets,LSSVM is the best tool to build a proxy *** the comparison of PSO and ICA shows that PSO is less time-consuming and more effective.

关键词： Proxy model LSSVM PSO ICA Sensitive analysis

Preliminary study on association between toxoplasmosis and breast cancer in Iran

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Asian Pacific Journal of Tropical Biomedicine 2015年第1期5卷 44-47页

作者： Narges Kalantari Salman Ghaffari Masomeh Bayani Maryam Mitra Elmi Daryush moslemi Novin Nikbakhsh Fariedh Ghavipanjeh Cellular and Molecular Biology Research Center Babol University of Medical Sciences Parasitology and Mycology Department Faculty of MedicineBabol University of Medical Sciences Infectious Diseases and Tropical Medicine Research Center Babol University of Medical SciencesBabolIran Radiography and Radiology Department Faculty of Paramedical SciencesBabol University of Medical Sciences Surgery Department Faculty of MedicineBabol University of Medical Sciences Laboratory Sciences Department Faculty of Paramedical SciencesBabol University of Medical Sciences

Objective:To investigate the possible association between Toxoplasma gondii(***)infection and breast cancer by examining the seropositivity and serointensity rate of anti-T gondii antibodies in breast cancer patients and healthy ***:This study was carried out on 66 women with breast cancer which consists of 29 newly diagnosed patients(Group 1) and 37 cases undergoing treatment and regular checkups(Group 2).Also,60 healthy women(Group 3) with no history of cancer confirmed by clinical examination and imaging participated in this *** participants were tested for *** immunoglobulin G(IgG) and immunoglobulin M(IgM) antibodies by enzyme-linked ***:The mean age of Groups 1.2 and 3 were 43.3±6.8,41.8±5.5 and 42.3±***(P=0.72).Overall.104(82.5%) and 8(6.3%) out of 126 women were positive for anti-T gondii IgG and IgM antibodies,*** seropositivity rate of *** antibodies(IgG) was seen in breast cancer patients(86.4%) compared with control group(78.3%)(P=0.24).IgG antibodies were detected in 89.2%of cancer patients under treatment.82.7%of newly diagnosed patients(P=0.18).IgM antibodies were found in 3(10.3%),2(5.4%)and 3(5%) in Groups 1.2 and *** significant difference was found between the mean titers of *** IgG antibody among these groups(P=0.87).Conclusions:This study did not find any significant association between toxoplasmosis and breast cancer besides higher rates of seropositivity and serointensity in patients compared with healthy volunteers.

关键词： Breast cancer Malignancy Toxoplasmosis Toxoplasma gondii

Phenytoin Effects on Proliferation and Induction of IL1<i>β</i>and PGE2 in Pediatric and Adults’ Gingival Fibroblasts

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Open Journal of Stomatology 2014年第9期4卷 452-462页

作者： Surena Vahabi Masomeh moslemi Bahareh Nazemisalman Zahra Yadegari Biotechnology Shahid Beheshti Medical University Tehran Iran Pedodontic Department Dental School Shahid Beheshti University of Medical Sciences Tehran Iran Pedodontic Department Dental School ZUMS Zanjan Iran Periodontics Department Dental School Shahid Beheshti University of Medical Sciences Tehran Iran

Background: Gingival Overgrowth (GO) is a well documented and unwanted side effect that occurs mainly as a result of certain antiseizure, phenytoin. The aim of this study was to compare the effect of phenytoin on proliferation and production of IL1β and PGE2 in cultured human gingival fibroblasts (HGF) of children and adults. Materials and Methods: Normal HGFs were obtained from 4 healthy children and 4 adult and then were cultured with phenytoin (20 mg/ml). MTT test was used to evaluate the proliferation and ELISA to determine the level of IL1β and PGE2 production by HGFs. Analysis of proliferation were assessed by Independent T-Test and ANOVA analysis was used to assess the level of IL1β and PGE2 production with an a error level less than 0.05. Results: The proliferation of HGF was not affected significantly by phenytoin in both cultured fibroblast sources (P > 0.05). Phenytoin induced a significantly higher formation of IL1β and PGE2 in child’s HGFs as compared to adult’s HGFs (P < 0.05). Conclusion: The results suggest that different inflammatory responses and cytokine formation by child’s and adult’s HGFs are the probable key elements that cause different reactions of phenytoin therapy. More advanced and systematic studies are needed to verify these findings.

关键词： Phenytoin Gingival Overgrowth Fibroblast Interleukin Children