COMPUTER-AIDED PREDICTION OF PHYSICAL AND MECHANICAL PROPERTIES OF HIGH STRENGTH CEMENTITIOUS COMPOSITE CONTAINING Cr2O3 NANOPARTICLES

ALI NAZARI,SHADI RIAHI 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2010 NANO Vol.5 No.5

In the present paper, two models based on artificial neural networks (ANN) and genetic programming (GEP) for predicting flexural strength and percentage of water absorption of concretes containing Cr2O3 nanoparticles have been developed at different ages of curing. For purpose of building these models, training and testing using experimental results for 144 specimens produced with 16 different mixture proportions were conducted. The data used in the multilayer feed forward neural networks models and input variables of genetic programming models are arranged in a format of eight input parameters that cover the cement content (C), nanoparticle content (N), aggregate type (AG), water content (W), the amount of superplasticizer (S), the type of curing medium (CM), Age of curing (AC) and number of testing try (NT). According to these input parameters, in the neural networks and genetic programming models the flexural strength and percentage of water absorption values of concretes containing Cr2O3 nanoparticles were predicted. The training and testing results in the neural network and genetic programming models have shown that every two models have strong potential for predicting the flexural strength and percentage of water absorption values of concretes containing Cr2O3 nanoparticles. Although neural network have predicted better results, genetic programming is able to predict reasonable values with a simpler method rather than neural network.

Honey Bee Mating Optimization Technique Based Multi-machine Power System Stabilizer Design

Ali Nazari,Amin Safari 보안공학연구지원센터 2013 International Journal of Smart Home Vol.7 No.3

Optimization of nano TiO2 pretreatment on free acid dyeing of wool using central composite design

ALI NAZARI,Mohammad Mirjalili,Navid Nasirizadeh,Shahab Torabian 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.21 No.1

The aim of the research is to investigate nano technique of wool acid dyeing without the presence of acidauxiliary agent at temperatures lower than the boiling. The wool fabrics are first pretreated with nanoTiO2 and BTCA at different concentrations. The dyeing process is then carried out on the pretreatedfabrics with C. I. Acid Blue 113 and C. I. Acid Black 3 dyes. Also, the central composite design analysis isapplied to design the relation between nano TiO2 and BTCA concentrations, and dye exhaustion. Theresponse surface methodology is also applied to find the optimum conditions for the wool fabricpretreatment. The scanning electron microscopy and X-ray diffraction are employed to indicate thepresence, crystal type and size of TiO2 nanoparticles on the wool surface. The pretreatment optimizationon the wool surfaces considerably enhances the absorption of acid dyes. The suggested methoddemonstrates the improvement of fastness properties than control dyeing and could be introduced as anew route, disclosing various desirablemulti-functional characteristics, to wool fabric. This technique isalso free from some of the disadvantages of acid chemical involved in dyeing such as damage to woolfabrics than wool conventional dyeing.

Mothproofing of wool fabric utilizing ZnO nanoparticles optimized by statistical models

ALI NAZARI,Majid Montazer,Mehdi Dehghani-Zahedani 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.6

Wool with high strength, elasticity, and resiliency has good dye-ability and comfort however could bedigested by keratinolytic enzymes. In this research, wool fabric pre-treated with BTCA and then treatedwith nano ZnO. The treated fabrics showed mothproofing activity against the larvae of carpet beetle,Anthrenus verbasci, as feeding protein fibers. The role of both BTCA and nano ZnO concentrations onmothproofing properties of the wool fabric were optimized using statistical model of response surfacemethodology (RSM). Mothproofing was investigated through assessing wool weight loss during feedingby A. verbasci. The analysis of variance (ANOVA) was utilized to obtain the optimum models for woolwith mothproofing properties. The damages on the wool surface confirmed with scanning electronmicroscopy and digital camera images. Further transmission and absorbance spectra approved the UVprotection properties of the nano ZnO treated wool in both UVA and UVB.

Superior Self-cleaning and Antimicrobial Properties on Cotton Fabrics Using Nano Titanium Dioxide along with Green Walnut Shell Dye

ALI NAZARI 한국섬유공학회 2019 Fibers and polymers Vol.20 No.12

In this study, functional cotton fabrics were prepared through applying nano titanium dioxide as photocatalyst andusing green walnut shell dye as both natural dye for coloration and agent capable of modifying TiO2 nanoparticles. Naturaldye extract of green walnut shells was used as photo sensitizer to fabricate titanium dioxide nanoparticles. Surfacemodification and coloration of cotton fabrics were performed by adding modified titanium dioxide nanoparticles inexhaustion bath. Produced cotton fabrics were characterized by field emission scanning electron microscope, energydispersiveX-ray spectroscopy and X-ray diffraction. Results indicated that all properties such as self-cleaning, antibacterialand antifungal of treated cotton fabric were superior with modified titanium dioxide compared to treated sample with TiO2alone. Moreover, the photocatalytic activity of titanium dioxide has no negative effect on fabric color.

Preparation of Electroconductive, Antibacterial, Photoactive Cotton Fabric Through Green Synthesis of ZnO/reduced Graphene Oxide Nanocomposite

ALI NAZARI 한국섬유공학회 2019 Fibers and polymers Vol.20 No.12

In this study, a simple and environment friendly approach was used to prepare the multifunctional compositefabrics via coating ZnO/reduced graphene oxide nanocomposite on the surface of cotton without any chemical reducingagent. Graphene oxide was coated on to commercial cotton fabric by dipping the fabric in graphene oxide solution and dryingin an oven. The nanocomposite was synthesized on cotton fabric in a single step by reduction of zinc acetate and grapheneoxide with pomegranate juice in the impregnation bath. X-ray diffraction spectroscopy, X-ray photoelectron spectroscopy,field emission scanning electron microscopy and energy dispersive spectroscopy confirmed the successful formation of ZnO/graphene nanocomposite on the fabric surface. The treated fabric had superior photocatalytic property in methylene bluedegradation, and had excellent antibacterial activity against Escherichia coli and Staphylococcus aureus bacteria. Furthermore, the electrical resistance of coated fabrics was decreased significantly by the presence of reduced graphene oxideon the surface of cotton fabrics.

Research on Nonlinear Automation for First Order Delays System

Ali Roshanzamir,Farzin Piltan,Arman Jahed,Saman Namvarchi,Nasri B. Sulaiman,Iman Nazari 보안공학연구지원센터 2015 International Journal of Hybrid Information Techno Vol.8 No.9

First order delay system (FODS) is in class of nonlinear systems. In these systems design control algorithms are very important. In this research nonlinear terms of incremental Proportional Integral Derivative (PID) algorithm is used to nonlinear model-free integrate large amounts of control methodology in a single methodology. This work, proposes a developed method to design nonlinear based PID controller. In this methodology nonlinear model-free sliding mode algorithm help incremental PID to estimate and linearization of first order delay system. According to this research, the controller robustness improved based on nonlinear term of sliding mode algorithm and the chattering is reduced/eliminate based on PID incremental method.

Effects of Loading Modes on Reliability of Cracked Structures Using FORM and MCS

Ali Delbariani-Nejad,Saeed Adib Nazari 한국정밀공학회 2017 International Journal of Precision Engineering and Vol.18 No.1

Studying the reliability of cracked structures under different types of failure modes such as a mixture of Mode I and Mode II loadings has been of great importance in many applications. The purpose of this study is to evaluate the effects of different modes of loading, i.e. pure Mode I, pure Mode II and Mixed mode I/II loadings on the reliability of cracked structures via three typical case studies including 1st: through crack in a very wide plate, 2nd: cracked pressurized fuselage and 3rd: cracked fastener holes under actual geometries and loading conditions using the FORM, the fracture toughness and the equivalent SIF for Mixed mode I/II loading which is extracted by the Energy release rate model 1. The MCS was used to check the accuracy of the FORM. It was found that the failure probability decreases significantly as the loading mode changes from the pure Mode I to pure Mode II. This means that the reliability in the Mixed mode I/II loading is higher than that of pure Mode I and smaller than for pure Mode II. Also, it was concluded that the failure probability decreases with increasing of the angle of crack for the Mixed mode I/II loading conditions. The results indicated that the angle of crack and the applied stress are the two variables which have the most significant influence on the reliability.

Adaptive Energy-Based Controllers for a Two Link Flexible Manipulator under Gravity

Sanaz Hosseini,Ali Fallah,Mahtab Nazari 제어로봇시스템학회 2008 제어로봇시스템학회 국제학술대회 논문집 Vol.2008 No.10

In this article, two adaptive, energy ?ased controllers are presented for regulation problem of planar two link flexible manipulator rotating in vertical plane under gravity. The first controller consists of a joint PD controller, an adaptive proportional controller which makes use of link curvature to suppress vibration and gravity compensation term. In second one a Lyapunov-based PD controller substitutes the joint PD. the effectiveness of the proposed controllers are shown and compared in the simulation results.

Neuroprotective effects of chloroquine on neurological scores, blood-brain barrier permeability, and brain edema after traumatic brain injury in male rats

Karimi Maryam,Nazari Somayeh,Shirani Faramarz,Alivirdiloo Vahid,Siahposht-Khachaki Ali,Edalatkhah Sepehr,Khanian Rama 대한신경집중치료학회 2023 대한신경집중치료학회지 Vol.16 No.1

Background: Traumatic brain injury (TBI) is one of leading causes of death among young people worldwide. Chloroquine, an antimalarial drug, has been shown to easily cross the blood-brain barrier (BBB) and inhibit autophagy in a variety of disorders, including Alzheimer disease and brain ischemia. We investigated the effects of chloroquine on neuronal protection after induction of brain trauma in male rats.Methods: A total of 120 male Wistar rats were treated with chloroquine at doses of 1.5, 3, and 6 mg/kg intraperitoneally after induction of diffuse TBIs. The veterinary coma scale was used to assess short-term neurological deficits. BBB disruption was evaluated using the Evans Blue dye method 6-hour post-injury. Vestibulomotor function was evaluated using the beam walk and beam balance methods. Histopathological changes in the brain tissue in different groups were evaluated using light microscopy and hematoxylin-eosin staining. Brain water and cerebrospinal fluid (CSF) contents of matrix metalloproteinase 9 (MMP-9) were assessed using the wet/dry method and enzyme-linked immunosorbent assay, respectively.Results: The results showed that injecting chloroquine (3 and 6 mg/kg) 30 minutes after TBI significantly reduced brain edema and BBB disruption, and recovered neurological deficits post-TBI (P<0.01). Furthermore, CSF MMP-9 was significantly reduced after administration of 1.5 mg/kg chloroquine (P<0.01).Conclusion: Chloroquine has neuroprotective effects in the brain, and thus, has the potential to mitigate the effects of brain trauma. It is possible that the anti-inflammatory and neurogenic effects of chloroquine are due to a decrease in MMP secretion in the CSF.