Two new species of Chrysis Linnaeus (Hymenoptera, Chrysididae) from Iran

Afrouz Farhad,Paolo Rosa,Ali Asghar Talebi,Yaghoub Fathipour,Hamidreza Hajiqanbar 한국응용곤충학회 2019 Journal of Asia-Pacific Entomology Vol.22 No.4

The Iranian species in the Chrysis pulchella and C. varidens species groups are investigated. Six species are recognized, two of which are described for the first time: Chrysis gamberoonensis Farhad, Rosa and Talebi sp. nov. and Chrysis brunneamarginata Farhad, Rosa and Talebi sp. nov.. Chrysis gamberoonensis Farhad, Rosa and Talebi sp. nov. belongs to the C. pulchella group and is recognizable within this species group by its unique blue body coloration, scattered mesosoma punctures, polished pit row with elongated pits, and a small median tooth on the lateral edge of metasomal tergum 3. Chrysis brunneamarginata Farhad, Rosa and Talebi sp. nov. belongs to the C. varidens group and is recognizable by the usually colorless apical rim of metasomal tergum 3, and the unique shape of the anterior corners of the scutellum which are enlarged, thickened and directed backward covering the axillary trough. Dichotomous keys and distributional data for Iranian species included in these species groups are provided. Chrysis schwarzi Linsenmaier, 1968 is raised to species rank. The number of Iranian Chrysis species and subspecies is raised to 122.

Novel ion-exchange nanocomposite membrane containing in-situ formed FeOOH nanoparticles: Synthesis, characterization and transport properties

Farhad Heidary,Ali Reza Khodabakhshi,Ali Nemati Kharat 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.4

A new type of cation-exchange nanocomposite membrane was prepared via in-situ formation of FeOOH nanoparticles in a blend containing sulfonated poly (2,6-dimethyl-1,4-phenylene oxide) and sulfonated polyvinylchloride by a simple one-step chemical method. Prepared nanocomposite membranes were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy and X-ray diffraction. The SEM images showed uniform dispersion of FeOOH nanoparticles throughout the polymeric matrices. The effect of additive loading on physicochemical and electrochemical properties of prepared cation-exchange nanocomposite membranes was studied. Various characterizations showed that the incorporation of different amounts of FeOOH nanoparticles into the basic membrane structure had a significant influence on the membrane performance and could improve the electrochemical properties.

A Report of Generalized Blood Flow Model with Heat Conduction Between Blood and Particles

Farhad Ali,Fazli Haq,Naveed Khan,Hessah Alqahtani,Anees Imtiaz,Ilyas Khan 한국자기학회 2022 Journal of Magnetics Vol.27 No.2

This paper examines the magneto hydrodynamic two-phase blood (Casson fluid) flow in a vessel with heat conduction between blood and particles. The temperature of both phases is also considered. The model for the flow under consideration is formulated in terms of partial differential equations. Then the classical model is generalized by utilizing the Caputo fractional order derivative. The generalized equations are then non-dimensionalized by using appropriate dimensionless variables. The exact dimensionless solutions are obtained via the joint application of Laplace & Hankel integral transforms. The influence of various embedded parameters on both the velocities (blood and magnetic particles) and the temperature distribution are presented graphically. It is worth noting that the particle and blood velocities decrease for increasing the values of magnetic parameter (H) which is useful to control the blood flow during magnetic therapy (for treating pain, such as the back, foot, or joint pain) and surgeries. It is worth noting that fractional model better describes the flow behavior than classical model by providing virous integral curves as shown in Fig.

Scale-up study of aerated coaxial mixing reactors containing non-newtonian power-law fluids: Analysis of gas holdup, cavity size, and power consumption

Ali Rahimzadeh,Farhad Ein-Mozaffari,Ali Lohi 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.113 No.-

The use of coaxial mixers has significantly improved gas dispersion in non-Newtonian fluids. However, tothe best of our knowledge, no scale-up investigation of an aerated coaxial mixer has been reported in theliterature. This study aims to explore the gas hold-up, energy dissipation rate, power consumption andcavity size in order to provide the guideline for scaling-up of the coaxial mixers. Through the use of computationalfluid dynamics and electrical resistance tomography, the effects of the aeration rate, centralimpeller type, rotating mode, impeller speed, and pumping direction on the gas dispersion efficacy inboth small-scale and large-scale coaxial mixers containing non-Newtonian fluids were investigated. For the coaxial mixer in the co-rotating mode, the same flow regime was achieved when the centralimpeller tip speed and the anchor impeller rotational speed were kept constant in both small-scaleand large-scale systems. It was observed that maintaining the aeration rate per volume of the non-Newtonian fluid constant was beneficial to preserve the performance of the large-scale coaxial mixerthe same as its small-scale counterpart. The use of specific power consumption as a scale up criterioneffectively improved the energy dissipation rate uniformity, which is critical for shear sensitiveapplications.

Hemodynamic Flow in a Vertical Cylinder with Heat Transfer

Farhad Ali,Anees Imtiaz,Ilyas Khan,Nadeem Ahmad Sheikh,Dennis Ling Chuan Ching 한국자기학회 2018 Journal of Magnetics Vol.23 No.2

In blood, the concentration of red blood cells varies with the arterial diameter. In the case of narrow arteries, red blood cells concentrate around the centre of the artery and there exists a cell-free plasma layer near the arterial wall due to Fahraeus-Lindqvist effect. Due to non-uniformity of the fluid in the narrow arteries, it is preferable to consider the two-phase model of the blood flow. The present article analyzes the heat transfer effects on the two-phase model of the unsteady blood flow when it flows through the stenosed artery under an external pressure gradient. The direction of the artery is assumed to be vertical and the magnetic field is applied along the radial direction of the artery. Blood is considered as a non-Newtonian Casson fluid with uniformly distributed magnetic particles. Both the blood and magnetic particles are moving with distinct velocities. This two-phase problem is modelled using the Caputo-Fabrizio derivative approach and then solved for an exact solution using joint Laplace & Hankel transforms. Effects of pertinent parameters such as Grashoff number, Prandtl number, Casson fluid parameter and fractional parameters, and magnetic field on blood velocity and particle velocity have been shown graphically for both large and small values of time. Both velocity profiles increase with the increase of Grashoff number and Casson fluid parameter and reduce with the increase of magnetic field and Prandtl number. The behaviour of temperature is studied for different values of the fractional parameter.

Design of Explicit Model Predictive Control for Constrained Linear Systems with Disturbances

Mohammad Ali Mohammadkhani,Farhad Bayat,Ali Akbar Jalali 제어·로봇·시스템학회 2014 International Journal of Control, Automation, and Vol.12 No.2

On-line model predictive control approaches require the online solution of an optimization problem. In contrast, the explicit model predictive control moves major part of computation offline. Therefore, eMPC enables one to implement a MPC in real time for wide range of fast systems. The eMPC approach requires the exact system model and results a piecewise affine control law defined on a polyhedral partition in the state space. As an important limitation, disturbances may reduce perfor-mance of the explicit model predictive control. This paper presents efficient approach for handling the problem of using eMPC for constrained systems with disturbances. It proposes an approach to improve performance of the closed loop system by designing a suitable state and disturbance estimator. Conditions for observability of the disturbances are considered and it is depicted that applying the disturbance’s estimation leads to rejection of the response error. It is also shown that the proposed approach prevents the reduction of feasible space. Simulation results illustrate the advantages of this approach.

Silica Sulfuric Acid as a Mild and Efficient Reagent for the Acetylation of Alcohols in Solution and under Solvent Free Conditions

Farhad Shirini*,Mohammad Ali Zolfigol,Kamal Mohammadi 대한화학회 2004 Bulletin of the Korean Chemical Society Vol.25 No.2

Introducing the Innovative Post-tensioned Connection with the Rigid Steel Node

Ali Jahangiri,Farhad Behnamfar,Mohammad Jahangiri 대한토목학회 2017 KSCE JOURNAL OF CIVIL ENGINEERING Vol.21 No.4

Securing strength, stiffness, and ductility in connections is one of the most important goals in structural design. After the Northridge earthquake, most steel moment resistant frames were damaged due to sudden fractures in beam-to-column connections. This resulted in the reconsideration of connection design and performance. As an alternative to weld connections, some researchers proposed the implementation of post-tensioned connections. In the present paper, the innovative connection is a combination of high strength steel frames which, through a rigid steel node above and below the beam flanges, provide the required stiffness, strength and ductility. Advantages of this connection include self-centering capability, lack of residual deformations, and energy dissipation which are analyzed using numerical and experimental methods. The modeling procedure and the cyclic behavior of the connection are studied and the analytical and the experimental results are compared. The results show that the cyclic responses observed in numerical simulations are in agreement with those from the experimental task and that the connection is superior to conventional moment resisting connections. The assumptions employed in simplifying simulations demonstrated high accuracy revealing an improvement in the seismic behavior of the connection.

Assessing Urban Land-use Development: Developing an Agent-based Model

Farhad Hosseinali,Ali A. Alesheikh,Farshad Nourian 대한토목학회 2015 KSCE JOURNAL OF CIVIL ENGINEERING Vol.19 No.1

We have developed an agent-based model of urban land-use sprawl for a case study area in Qazvin province of Iran that brings therisk-explicit attitudes of land-use developers into consideration. For this purpose, new methods for searching landscapes, forselecting parcels to develop, and for allowing competitions among agents have been considered and implemented. The agents are offive categories; they act as mobile developers, and have several land-related objectives. Our proposed model evaluates two majorcases of regarding and disregarding risk for categorizing the agents. The model uses the data of the year 2005 to be calibrated and theresults are evaluated with data of the year 2010. The results revealed that while the risk-disregarding case was slightly better thanrisk-regarding in predicting the location of developments, the later was a better method to produce contiguous patches ofdevelopments. The model achieved the value of 82.15% measured by Kappa index in predicting the occurred developments. Therefore, it is considered here that using the attitudes of people towards risk along with appropriate weights for criteria maps helpthe model to simulate land-use developments with acceptable accuracy and more contiguous parcels.

Development of a kinetic model for Fischer–Tropsch synthesis over Co/Ni/Al2O3 catalyst

Farhad Fazlollahi,Majid Sarkari,Akbar Zare,Ali Akbar Mirzaei,Hossein Atashi 한국공업화학회 2012 Journal of Industrial and Engineering Chemistry Vol.18 No.4

In the present research an active Co–Ni/Al2O3 catalyst was prepared by impregnation method for synthesis of light olefins in Fischer–Tropsch synthesis. After studying the effects of using optimized operating conditions on catalyst performance, the kinetic experimental study was performed in a differential micro-fixed-bed-reactor by altering reaction temperature (230–270 8C), pressure (2–12 bar),gas hourly space velocity (2000–7200 h-1) and H2/CO feed molar ratio (1–3). Based on Langmuir–Hinshelwood–Hougen–Watson (LHHW) approach, seven different two-parameter kinetic models were considered. The kinetic data of this study were fitted accurately by a simple form -rCO ¼APCOPH2 =ð1 þ bPCOP0:5H2Þ2 that assumed the following kinetically relevant steps, where CO dissociates via interaction with adsorbed hydrogen; the first hydrogenation step of the surface carbon was reversible and fast, while the second one was slow and rate determining. The kinetic parameters were determined using Levenberg–Marquardt (LM) method and the apparent activation energy and heat of adsorption were 78.70 kJ/mol and -14.16 kJ/mol, respectively.