Mechanical, rheological, and durability analysis of self-consolidating concretes containing recycled aggregates

Hiwa Mollaei,Taleb Moradi Shaghaghi,Hasan Afshin,Reza Saleh Ahari,Seyed Saeed Mirrezaei 국제구조공학회 2023 Structural Engineering and Mechanics, An Int'l Jou Vol.88 No.2

In the present paper, the effect of recycled aggregates on the rheological and mechanical properties of selfconsolidating concrete is investigated experimentally and numerically. Hence, the specimen with two types of recycled aggregates, i.e., known and unknown resistance origins, are utilized for the studied specimens. The experiments in this study are designed using the Box-Behnken method, which is one of the response surface methods. Input variables in mixtures include silica fume in the range of 5-15% as a percentage substitute for cement weight and recycled coarse and fine aggregates in the range of 0-50% for both series of recycled materials as a substitute for natural materials. The studied responses are slump flow, V funnel, compressive strength, tensile strength, and durability. The results indicate that the increase in the amount of recycled aggregates reduces the rheological and mechanical properties of the mixtures, while silica fume effectively improves the mechanical properties. In addition, the results demonstrate that the fine recycled aggregates affect the total response of the concrete significantly. The results of tensile and compressive strengths indicate that the mixtures including 50% recycled materials with known resistance origin demonstrate better responses up to 8 and 10% compared to the materials with unknown resistance origins, respectively. Recycled materials with a specific resistance origin also show better results than recycled materials with an unknown resistance origin. Durability test results represent those concretes containing recycled coarse aggregates have lower strength compared to recycled fine aggregates. Also, a series of mathematical relationships for all the responses are presented using variance analysis to predict mixtures’ rheological and mechanical properties.

The effects of 24-epibrassinolide corm priming and foliar spray on morphological, biochemical, and postharvest traits of sword lily

Samaneh Mollaei,Homayoun Farahmand,Iraj Tavassolian 한국원예학회 2018 Horticulture, Environment, and Biotechnology Vol.59 No.3

Gladiolus, or sword lily, is one of the most important cut flowers worldwide. Enhancement of its traits is of paramount importance to the flower industry. The application of 24-epibrassinolide (EBR) by corm priming and plant foliar spray to improve morphological, biochemical and postharvest characteristics of Gladiolus grandiflorus cv. Oscar were investigated. Concentrations of 0.5, 1, and 2 µM EBR as well as distillated water as a control were used for both corm priming and foliar spray treatments. Results showed that the highest levels of corm sprouting and flower spike emergence were obtained at 1 µM EBR. Floret numbers, flower spike fresh and dry weight, and vase life showed the highest values at 1 µM EBR combined treatments. The combination of corm priming at 2 µM and foliar spay at 1 µM EBR, showed the highest effect on malondialdehyde reduction. The highest activities of antioxidant enzymes such as catalase, peroxidase, and superoxide dismutase were obtained in combination of 1 µM EBR corm priming and 1 µM EBR foliar spray. EBR treatments prolonged vase life from 8 to 14 days and significantly improved gladiolus morphological and biochemical traits.

Effect of extrusion of soybean meal on feed spectroscopic molecular structures and on performance, blood metabolites and nutrient digestibility of Holstein dairy calves

Berenti, Ammar Mollaei,Yari, Mojtaba,Khalaji, Saeed,Hedayati, Mahdi,Akbarian, Amin,Yu, Peiqiang Asian Australasian Association of Animal Productio 2021 Animal Bioscience Vol.34 No.5

Objective: Performance and physiological responses of dairy calves may change by using extruded soybean meal (ESBM) instead of common soybean meal (SBM) in starter feed. The aims of the current study were i) to determine the effect of extrusion processing of SBM on protein electrophoretic size, fourier transform infrared spectroscopy (FTIR) structures and Cornell Net Carbohydrate and Protein System (CNCPS) protein subfractions and ii) to determine the effect of substitution of SBM with ESBM in starter feed of Holstein heifer calves during pre and post-weaning on performance, nutrient digestibility, and blood metabolites. Methods: The SBM was substituted with ESBM at the level of 0%, 25%, 50%, 75%, and 100% (dry matter [DM] basis). Fifty heifer calves (initial body weight 40.3±0.63 kg) were used for the study. After birth, animals were fed colostrum for 3 days and then they were fed whole milk until weaning. Animals had free access to starter feed and water during the study. Results: Extrusion of SBM decreased electrophoretic protein size and increased rapidly degradable true protein fraction, changed FTIR protein and amide II region. With increasing level of ESBM in the diet, starter intake increased quadratically during the pre-weaning period (p<0.05) and body weight, DM intake and average daily gain increased linearly during the post-weaning and the whole study period (p<0.05). Tbe DM and crude protein digestibilities at week 14 and blood glucose and beta hydroxybutyric acid increased linearly in calves as the level of ESBM increased in the diet (p<0.05). Conclusion: Dairy calves performance and physiological responses were sensitive to SBM protein characteristics including electrophoretic size, FTIR structures and CNCPS protein fractions.

Free vibration analysis of FG porous joined truncated conical-cylindrical shell reinforced by graphene platelets

Kiarasi, Faraz,Babaei, Masoud,Mollaei, Somayeh,Mohammadi, Mokhtar,Asemi, Kamran Techno-Press 2021 Advances in nano research Vol.11 No.4

Natural frequency analysis of functionally graded porous joined truncated conical-cylindrical shell reinforced by graphene platelet is investigated in this paper. The structure is consisting of a layered model with five kinds of distribution of graphene platelets in a metallic matrix containing open-cell interior pores. To calculate the effective properties of the porous nanocomposite joined shell, the generalized rule of mixture and the modified Halpin-Tsai equations are employed. Four different porosity distributions are assumed along the shell thickness: two kinds of symmetric functionally graded distributions, non-symmetric functionally graded distributions and uniform distribution of porosity. Graded finite element method (GFEM) based on Rayleigh-Ritz energy formulation has been used to solve 2D- axisymmetric elasticity equations. A parametric study is also conducted to show the effects of different geometric parameters, boundary conditions, weight fraction of graphene platelets, porosity coefficient, distribution of porosity and dispersion pattern of graphene platelets on the natural frequencies and mode shapes of the structure.

Evaluation of JC and Cytomegalo Viruses in Glioblastoma Tissue

Afshar, Reza Malekpour,Mollaei, Hamid Reza,Zandi, Bahare,Iranpour, Maryam Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.11

Glioblastoma multiforme (GBM) is the most aggressive of the gliomas, a collection of tumors arising from glia in the central nervous system. Possible associations between the human cytomegalovirus (HCMV) and the JC virus with GBM are now attracting interest. Our present aim was to investigate the prevalence of the two viruses in Iranian patients from Kerman's cities in the south of Iran. In addition, the expression rates of pp65, large T antigen and p53 proteins were assessed and their relation with GBM evaluated using reverse transcription real time PCR (rReal Time PCR). A total of 199 patients with GBM cancer were enrolled, with $mean{\pm}SD$ ages of $50.0{\pm}19.5$ and $50.7{\pm}19.6$ years for males and females, respectively. The P53 rate was dramatically low suggesting an aetiological role,. Large T antigen expression was found in JC positive samples, while the PP65 antigen was observed in patients positive for CMV and JC. HCMV products and JC virus with oncogenic potential may induce the development of various tumors including glioblastomas. The JC virus produces an early gene product, T-antigen, which has the ability to associate with and functionally inactivate well-studied tumor suppressor proteins including p53 and pRB.

Numerical solution of beam equation using neural networks and evolutionary optimization tools

Babaei, Mehdi,Atasoy, Arman,Hajirasouliha, Iman,Mollaei, Somayeh,Jalilkhani, Maysam Techno-Press 2022 Advances in computational design Vol.7 No.1

In this study, a new strategy is presented to transmit the fundamental elastic beam problem into the modern optimization platform and solve it by using artificial intelligence (AI) tools. As a practical example, deflection of Euler-Bernoulli beam is mathematically formulated by 2nd-order ordinary differential equations (ODEs) in accordance to the classical beam theory. This fundamental engineer problem is then transmitted from classic formulation to its artificial-intelligence presentation where the behavior of the beam is simulated by using neural networks (NNs). The supervised training strategy is employed in the developed NNs implemented in the heuristic optimization algorithms as the fitness function. Different evolutionary optimization tools such as genetic algorithm (GA) and particle swarm optimization (PSO) are used to solve this non-linear optimization problem. The step-by-step procedure of the proposed method is presented in the form of a practical flowchart. The results indicate that the proposed method of using AI toolsin solving beam ODEs can efficiently lead to accurate solutions with low computational costs, and should prove useful to solve more complex practical applications.

A Simple Low Pressure Method for the Synthesis of TiO2 Nanotubes and Nanofibers and Their Application in DSSCs

Masoud Karimipour,Sara Mashhoun,Mohsen Mollaei,Mehdi Molaei,Nima Taghavinia 대한금속·재료학회 2015 ELECTRONIC MATERIALS LETTERS Vol.11 No.4

TiO2 nanotubes were synthesized using a modified autoclave-free thermal method from as-prepared initial powders. The size of initial powders (IP) was found to be critical in determining the morphology and crystal structure of the final product. Oleylamine (OA) was used as the polymer agent in the preparation of initial powders with different mol ratios of OA/Ti: 1, 5, and 10. X-ray diffraction analysis depicted that the increase of mole ratio up to 10 resulted in smaller nanoparticles with the sizes of about 8 nm. It was also deliberated that low temperature thermally treated IP showed the characteristic diffraction pattern of titanate phase of nanotubes. Scanning electron microscope images showed nanorods, short nanotubes, and single-phase long and uniform nanofibers produced from initial powders. SEM cross-section of the anode cell of TiO2 nanofibers demonstrated the presence of uniformly closed net long fibers in the cell. Open circuit voltage measurements of the nanofiber cell demonstrated a several hundreds of seconds in the electron transport decay, which was significantly higher than that of the nanoparticles. IMPS/IMVS measurements of the nanofibers and nanotube solar cells showed electron transport enhancement and long life time compared to their nanoparticle counterparts.

Interference of oxygen during the solution combustion synthesis process of ZnO particles: Experimental and data modeling approaches

E. Garmroudi Nezhad,F. Kermani,Z. Mollaei,M. Mashreghi,J. Vahdati Khakhi,S. Mollazadeh 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.107 No.-

In the present study, the ratio of reducing to oxidizing (F/O) elements as an indicator for maximumoxygen interference during the solution combustion synthesis (SCS) process of ZnO particles was determinedusing simple mathematical calculations. The obtained result was called special point (S.P). Tointerpret the role of S.P in the SCS reactions, ZnO particles were synthesized in the presence of citric acid,hexamine, hydrazine, and urea with various F/O values (0.75, 1, 1.25). The correlations between the S.P,physicochemical properties of the synthesized ZnO powders, and density functional theory (DFT) predictionswere investigated. X-ray diffraction results, band-gap values, oxygen vacancy data, DFT results, andS.P points demonstrated the direct relation of these parameters. According to the S.P idea, it can beaffirmed that the structural defects, particle size, optical band-gap (Eg = 3.06), the color of the products,the magnetic properties (0.2 emu/g), and the antibacterial inhibitory (15.625 mg/mL) of the synthesizedparticles were controlled via the interference of O2 during the synthesis process. In fact, the S.P investigationwas suggested that the reaction rate of the combustion synthesis process could regulate the propertiesof ZnO particles.

Human parvovirus B19 in patients with beta thalassemia major from Tehran, Iran

Seyed Ali Mohammad Arabzadeh,Farideh Alizadeh,Ahmad Tavakoli,Hamidreza Mollaei,Farah Bokharaei-Salim,Gharib Karimi,Mohammad Farahmand,Helya Sadat Mortazavi,Seyed Hamidreza Monavari 대한혈액학회 2017 Blood Research Vol.52 No.1

Background: Due to the tropism of human parvovirus B19 to erythroid progenitor cells, infection in patients with an underlying hemolytic disorder such as beta-thalassemia major leads to suppression of erythrocyte formation, referred to as transient aplasia crisis (TAC), which may be life-threatening. We investigated the prevalence of parvovirus B19 among patients with beta thalassemia major attending the Zafar Adult Thalassemia Clinic in Tehran, Iran. Methods: This cross-sectional study was performed to determine the presence of parvovirus B19 DNA in blood samples and parvovirus B19 genotypes in plasma samples of patients with thalassemia major. The population consisted of 150 patients with beta-thalassemia major who attended the Zafar clinic in Tehran. Specimens were studied using a real-time poly-merase chain reaction assay. Results: The prevalence of parvovirus B19 in our study population was 4%. Of 150 patients with thalassemia, six (4%) were positive for B19 DNA. There was no significant correlation between blood transfusion frequency and B19 DNA positivity. Finally, phylogenetic analy-sis of human parvovirus B19 revealed genotype I in these six patients. Conclusion: In this study, acute B19 infections were detected in patients with beta thalassemia major. Screening of such high-risk groups can considerably reduce the incidence and prevalence of B19 infection; thus, screening is required for epidemiologic surveillance and dis-ease-prevention measures.

Detection of Epstein-Barr Virus and Cytomegalovirus in Gastric Cancers in Kerman, Iran

Leila, Zaruni,Arabzadeh, Seyed Alimohammad,Afshar, Reza Malekpour,Afshar, Abbas Aghaei,Mollaei, Hamid Reza Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.5

Gastric cancer (GC) is a multifactorial disease with different factors having roles in its genesis. Helicobacter pylori and Epstein-Barr virus (EBV) are known infectious agents that could contribute. In addition, there is evidence of a relationship with cytomegalovirus (CMV). Since data on CMV prevalence in gastric cancer are limited, we here evaluated the frequency of EBV and CMV in Iranian patients. Ninety paraffin blocks of GC tissues from patients in Kerman were evaluated for the presence of EBV and CMV genomes by real-time polymerase chain reaction. EBV was detected in 10 cases (11.1%) and CMV in seven. One out of 17 female patients (5.88%) and nine out of 73 male patients (12.3%) were positive for EBV, while one out of 17 female patients (5.88%) and six out of 73 male patients (8.22%) were positive for CMV. The mean age for EBV-positive patients was $60.5{\pm}14.9years$ and the mean age for CMV-positive patients was $67.9{\pm}12.3years$. This study shows that the frequency of EBV-associated GC is high in Kerman. It also indicates that further studies of associations between GC and CMV are warranted, covering larger samples and populations from different areas of the world.