Estimation of yield strength due to neutron irradiation in a pressure vessel of WWER-1000 reactor based on the correction of the secondary displacement model

Moslemi-Mehni Elaheh,Khoshahval Farrokh,Pour-Imani Reza,Amirkhani-Dehkordi M.A. 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.9

Due to neutron radiation, atomic displacement has a significant effect on material in nuclear reactors. A range of secondary displacement models, including the Kinchin-Pease (KeP), Lindhard, NorgettRobinson-Torrens (NRT), and athermal recombination-corrected displacement per atom (arc-dpa) have been suggested to calculate the number of displacement per atom (dpa). As neutron elastic interaction is the main cause of displacement damage, the focus of the current study is to calculate the atomic displacement caused by the neutron elastic interaction in order to estimate the exact amount of yield strength in a WWER-1000 reactor pressure vessel. To achieve this purpose, the reactor core is simulated by MCNPX code. In addition, a program is developed to calculate the elastic radiation damage induced by the incident neutron flux (RADIX) based on different models using Fortran programming language. Also, due to non-elastic interaction, the displacement damage is calculated by the HEATR module of the NJOY code. ASME E-693-01 standard, SPECTER, NJOY codes, and other pervious findings have been used to validate RADIX results. The results showed that the RADIX(arc-dpa)/HEATR outputs have appropriate accuracy. The relative error of the calculated dpa resulting from RADIX(arc-dpa)/HEATR is about 8% and 46% less than NJOY code, respectively in the ¼ and ¾ vessel wall.

Preparation of mullite-HfN composites through spark plasma sintering: investigation of the microstructure and mechanical properties

Moslemi-firoozabadi Hamidreza,Manafi Sahebali,Ghahremani Davoud 한국세라믹학회 2022 한국세라믹학회지 Vol.59 No.6

This study focused on the production of mullite ceramic and composites containing HfN reinforcements through spark plasma sintering. Accordingly, 5, 10 and 15wt% HfN powders with calcined Aluminum nitrate nonahydrate (ANN) and colloidal silica mixture were blended through a high-energy mixer mill in ethanol media. Spark plasma sintering of mullite ceramic and composite was performed under almost the same condition consisting of the initial and fi nal applied pressure of 10 and 50 MPa, respectively, vacuum of 15–25 Pa, and the maximum sintering temperature of 1350 °C. The measured relative den- sities showed the nearly full densifi cation of all prepared samples. The XRD patterns also depicted perfect mullitization for the mullite sample, while in the sintered composites, mullite, HfN and HfO 2 peaks were obtained as the crystalline phases. The uniform distribution of HfN and HfO 2 as the reaction products of ANN water desorption was recognized in the micro- structure of mullite composites with 5 and 10 wt% HfN samples. Meanwhile, the mullite-15wt% HfN composite displayed some agglomerates and porosities. The attained mechanical properties also showed that Vickers hardness was increased by raising HfN contents. However, the maximum bending strength of 424 ± 25 and fracture toughness of 3.74 ± 0.22 MPa  m 1/2 were achieved for the composite containing 10 wt% HfN.

Bayesian Survival Analysis of High-Dimensional Microarray Data for Mantle Cell Lymphoma Patients

Moslemi, Azam,Mahjub, Hossein,Saidijam, Massoud,Poorolajal, Jalal,Soltanian, Ali Reza Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.1

Background: Survival time of lymphoma patients can be estimated with the help of microarray technology. In this study, with the use of iterative Bayesian Model Averaging (BMA) method, survival time of Mantle Cell Lymphoma patients (MCL) was estimated and in reference to the findings, patients were divided into two high-risk and low-risk groups. Materials and Methods: In this study, gene expression data of MCL patients were used in order to select a subset of genes for survival analysis with microarray data, using the iterative BMA method. To evaluate the performance of the method, patients were divided into high-risk and low-risk based on their scores. Performance prediction was investigated using the log-rank test. The bioconductor package "iterativeBMAsurv" was applied with R statistical software for classification and survival analysis. Results: In this study, 25 genes associated with survival for MCL patients were identified across 132 selected models. The maximum likelihood estimate coefficients of the selected genes and the posterior probabilities of the selected models were obtained from training data. Using this method, patients could be separated into high-risk and low-risk groups with high significance (p<0.001). Conclusions: The iterative BMA algorithm has high precision and ability for survival analysis. This method is capable of identifying a few predictive variables associated with survival, among many variables in a set of microarray data. Therefore, it can be used as a low-cost diagnostic tool in clinical research.

Modeling of heterogeneous fenton process using catalyst produced from date palm waste for dye removal: Catalyst characterization and process optimization

Moslemi Faeze,Ehrampoush Mohammad Hassan,Mehralian Mohammad,Dalvand Arash 한국화학공학회 2023 Korean Journal of Chemical Engineering Vol.40 No.11

This study evaluated the efficiency of the heterogeneous Fenton process using magnetic activated carbon catalyst produced from date palm waste in removing direct dye from aqueous solutions. The experimental runs and optimal conditions for the effect of contact time, solution pH, catalyst dose, and persulfate dose were determined based on the Box-Behnken design under response surface methodology (RSM). FTIR, FESEM, XRD, EDS, BET, and VSM analyses were used to investigate the characteristics of the catalyst. The analysis of variance (ANOVA) verified that the selected statistical model with R2 0.95, p-value<0.0001, and F-value 58.67 was significant. The results of optimal conditions showed that at a dye concentration of 50 mg/L, catalyst dose 0.96 g/L, persulfate dose 9.7 mM, pH 7 and contact time 84 min, maximum removal efficiency of DR80, DB80, DBw103 and COD was 92.69, 97.07, 73.85, and 60%, respectively. After five cycles of catalyst regeneration, the results showed that the catalyst could be utilized several times effectively for dye removal.

Food Behaviors and Its Association with Hypertension and Cardiovascular Diseases in Sowme’eh Sara (North of Iran): The PERSIAN Guilan Cohort Study (PGCS)

Masoumeh Moslemi,Marjan Mahdavi-Roshan,Farahnaz Joukar,Mohammadreza Naghipour,Fariborz Mansour-Ghanaei 한국식품영양과학회 2021 Preventive Nutrition and Food Science Vol.26 No.3

Food behavior and dietary pattern are major parameters affecting the health status of people. The objective of this study was investigation of food behaviors in people inhabited in North of Iran to find out association of the effective indices (related to salt and fried foods) with hypertension and other cardiovascular diseases (CVDs). This large cross-sectional study was conducted on 10,520 participants and their sociodemographic, medical, and food behavior information were evaluated. Association of salt intake with CVDs and stroke was studied by portfolio at risk (PAR) formula. Association of food behavior with hypertension and CVDs was surveyed by chi-square test. Differences were significant at P≤ 0.05. Analysis of medical information revealed that 43.18% and 8.18% of the participants had hypertension and CVDs, respectively; mostly in women. Significant association was observed between salt-related behaviors and hypertension in the participants. Regarding salt intake, higher PARs were calculated in women than men (2.26 vs. 1.88 for PARCVDs and 3.66 vs. 3.05 for PARstroke), and urban than rural inhabitants (4.56 vs. 3.66 for PARCVDs and 7.27 vs. 5.88 for PARstroke). No significant contribution was observed between oil-related behaviors and CVDs. The majority of participants were well-informed about appropriate preparation and consumption of fried foods but not a healthy behavior about salt intake. Considering the significant association of salt-related behaviors with hypertension, conducting educational programs by healthcare practitioners in the population is suggested.

A Comparison between Three Numerical Criteria for Prediction the Forming Limit Diagram of St14 Steel

M. Moslemi,S.J. Hosseinipour,M.E. Hosseini,A.H. Gorji 한국소성가공학회 2011 기타자료 Vol.2011 No.8

In this paper, the forming limit diagram (FLD) of a low carbon steel St14 (DIN 1623) is investigated experimentally and numerically. The objective of this study is to find a numerical criterion which enables a simple and reliable determination of the FLD. For this purpose, Out-of-plane stretching test method with hemispherical punch was simulated by using commercial finite element software, ABAQUSE 6.9. One-quarter of the geometry was used due to symmetry. The material was modeled as elastoplastic and the anisotropic properties were described by the Hill quadratic yield criterion. The model was assumed to be rate independent. Coulomb friction law was defined for all contact surfaces. The simulation process was performed in two steps. In the first step the blank-holder moves down and deforms the blank into the draw-bead. Then the punch moves up at 20 increments and deforms the specimen to a specified displacement. Three numerical criteria including maximum second thickness strain derivative (CRIT1), equivalent plastic strain increment ratio (CRIT2), and total equivalent plastic strain ratio (CRIT3) were evaluated and the forming limit curve (FLC) were obtained. The predicted FLC were compared with experimental data. Unlike the CRIT2, the CRIT1 and CRIT3 were in good agreements with were experimental data. The CRIT1 criterion predicted the lower bound of the experimental results. While by using the CRIT3 criterion both the lower and upper bounds of the experimental results were predicted.

A review on electrochemical behavior of pyrite in the froth flotation process

Hossein Moslemi,Mahdi Gharabaghi 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.47 No.-

Metal sulfides are usually semiconductor and cause electrochemical reactions. This phenomenon playsan important role in sulfideflotation. Pyrite as the most abundant sulfide mineral is often associated withvaluable sulfide minerals, coal and gold. It is very important to study its electrochemical behavior in theflotation process. This review focuses on researches carried out over the past several decades that havestudied electrochemical processes associated with pyrite occurring duringflotation. The mechanism ofprocesses such as oxidation, activation, depression, and interactions of activated and non-activatedsurfaces with collectors as well as factors affecting them are described. Moreover, the effect ofelectrochemical conditions during grinding on theflotation process is also discussed. It has been foundthat moderately oxidizing conditions are favorable for collector-lessflotation of pyrite while stronglyreducing or oxidizing potentials lead to its depression. Increasing the electrochemical potential not onlyhas a deleterious effect on the activation of pyrite by copper, but also facilitates its depression bydepressants. In the case of the adsorption of xanthate whether on activated or non-activated surfaces, agreat increase or decrease in the potential has adverse effects and it is necessary to optimize theelectrochemical conditions. Various factors such as pH, solid percentage, particle size distribution,flotation time, type and concentration of reagents and oxygen content as well as grinding conditions canaffect the intensity of these electrochemical interactions. It is proposed that further researches usingadvanced chemical analysis techniques are needed to understand the electrochemical processes involvedinflotation systems.

Cost-effectiveness dynamics and vibration of soft magnetoelastic plate near rectangular current-carrying conductors

Ali Asghar Moslemi Beirami,Vadim V. Ponkratov,Amir Ebrahim Akbari Baghal,Barno Abdullaeva,Mohammadali Nasrabadi 국제구조공학회 2023 Structural Engineering and Mechanics, An Int'l Jou Vol.88 No.2

Cost-effective high precision hybrid elements are presented in a hierarchical form for dynamic analysis of plates. The costs associated with controlling the vibrations of ferromagnetic plates can be minimized by adequate determination of the amount of electric current and magnetic field. In the present study, the effect of magnetic field and electric current on nonlinear vibrations of ferromagnetic plates is investigated. The general form of Lorentz forces and Maxwell's equations have been considered for the first time to present new relationships for electromagnetic interaction forces with ferromagnetic plates. In order to derive the governing nonlinear differential equations, the theory of third-order shear deformations of three-dimensional plates has been applied along with the von Kármán large deformation strain-displacement relations. Afterward, the nonlinear equations are discretized using the Galerkin method, and the effect of various parameters is investigated. According to the results, electric current and magnetic field have different effects on the equivalent stiffness of ferromagnetic plates. As the electric current increases and the magnetic field decreases, the equivalent stiffness of the plate decreases. This is a phenomenon reported here for the first time. Furthermore, the magnetic field has a more significant effect on the steady-state deflection of the plate compared to the electric current. Increasing the magnetic field and electric current by 10-times results in a reduction of about 350% and an increase of 3.8% in the maximum steady-state deflection, respectively. Furthermore, the nonlinear frequency decreases as time passes, and these changes become more intense as the magnetic field increases.

최근의 파티클보오드 공업의 발전

모스레미 한국목재공학회 1980 목재공학 Vol.8 No.3

임산공업에서의 목재에너지

모스레미 한국목재공학회 1980 목재공학 Vol.8 No.3