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Habeeb H.,Thiqar University | Chandra S.,Indian Institute of Technology Roorkee | Nashaat Y.,University of Diyala
KSCE Journal of Civil Engineering | Year: 2014

The present study explains the effect of aggregate gradation on moisture damage in bituminous mixes. Three types of aggregate gradation, two types of binder; VG-30 and Polymer modified bitumen (PMB-40) and two types of mixes Bituminous Concrete (BC) and Dense Bituminous Macadam (DBM) are used. Moisture susceptibility tests like retained stability and tensile strength ratio are conducted on Marshall specimens. The static creep test was also conducted for conditioned and unconditioned specimens to observe the effect of moisture on creep behaviour. The results indicate that Marshall stability and flow values are higher in PMB-40 mixes than in VG-30 mixes. Moisture susceptibility of PMB-40 mixes is low when compared with mix using VG-30. The reduction in retained stability, and Indirect Tensile Strength (ITS) and increase in creep are evaluated for finer, coarser and normal gradation of aggregates to observe the effect of gradation on moisture susceptibility of mixes. The retained stability is least affected when compared with other moisture susceptibility parameters. Also, gradation parameters s1 and Gradation Ratio (GR) are introduced in this paper to establish relation between aggregate gradation and moisture susceptibility and permanent deformation. Models are suggested to estimate rut depth from ITS and stability values. © 2014 Korean Society of Civil Engineers and Springer-Verlag Berlin Heidelberg.

Mushatet K.S.,Thiqar University | Wahab A.K.A.,University of Babylo | Ajeel W.H.,University of Babylo
Advanced Materials Research | Year: 2012

In this paper, an experimental and numerical study has been conducted to investigate the performance and dynamic effects of the centrifugal pump. Two impellers having different diameters were tested. The aim of the present study is to extend the scientific research of the related studies to high speed centrifugal pump which has a logarithmic profile. The variation of dynamic pressure fluctuations on the front wall of volute casing around the impeller is predicted at different values of volume flow rates. Also the pump performance was tested for the considered values of the volume flow rate. The governing partial differential equations of continuity and momentum were dicretised to algebraic equations by using CFD commercial code(FLUENT 6.3). This code has the ability to transfer the complex physical domain to a computational one by using GAMBIT software. The effect of turbulence was simulated by using a standard k-ε model. The obtained results show th at the dynamic pressure fluctuations significantly dependent on angular position and volume flow rate. It is observed that the pump efficiency is increased as impeller diameter increases. © (2012) Trans Tech Publications.

Bari S.S.,Panjab University | Magtoof M.S.,Thiqar University | Bhalla A.,Panjab University
Monatshefte fur Chemie | Year: 2010

An operationally simple and efficient approach for the synthesis of azetidin-2,3-diones is described. The starting substrate 2-(2-bromobenzyloxy) ethanoyl chloride was treated with appropriate Schiff's bases in triethylamine and dichloromethane to afford 3-(2-bromobenzyloxy)azetidin-2-ones. The synthesis of azetidin-2,3-diones was successfully achieved via radical mediated rearrangement of appropriately substituted 3-(2-bromobenzyloxy)azetidin-2-ones using n-tributyltin hydride and AIBN in refluxing dry benzene. © Springer-Verlag 2010.

Mushatet K.S.,Thiqar University
Advanced Materials Research | Year: 2012

In this paper, A numerical study has been done to predict the heat transfer of the staggered ribbed backward facing step flow with inclined impinging jet flow. The impinging jet flow was inclined towards the main cross flow and the angle of inclination is ranged from 30° to 90°. The ribs were in staggered arrangement and aligned after the slot jet in normal direction to the main cross flow. The effect of angle of inclination and contraction ratio on thermal field was studied for jet and channel Reynolds number of 20000 and 16000 respectively. The aim of the present study is to verify how adding staggered ribs with inclined jet flow to the problem of backward facing can enhance the rate of heat transfer. The governing partial differential equations of continuity, Navier-Stockes and energy was discretised on non-uniform staggered grid by using finite volume method. The discretised algebraic equations were solved by using a built home computer program based on simple algorithm. The conducted results show that the considered flow geometry increased noticeably the rate of heat transfer for the studied contraction ratios and angle of inclination. It was observed that the rate of heat transfer is decreased as angle of inclination increases. © (2012) Trans Tech Publications.

Hello K.M.,Al Muthanna University | Mihsen H.H.,University of Basrah | Mosa M.J.,University of Basrah | Magtoof M.S.,Thiqar University
Journal of the Taiwan Institute of Chemical Engineers | Year: 2015

A novel catalyst has been developed toward the production of second generation (2G) biofuels instead of using the expensive enzymes. Salicylaldehyde phenylhydrazone was immobilized onto silica rice husk ash to form a heterogeneous catalyst denoted as RHPHMP. The BET measurements of the catalyst showed that the surface area to be 194m2/g with pore size distribution fall within the microporous region. The FT-IR clearly showed the presence of NH and CN absorption bands at the expected range. The elemental and EDX analysis of RHPHMP showed the nitrogen is included into the catalyst structure. The RHPHMP was efficient for the hydrolysis of cellulose, with maximum glucose yield over 82% at 140°C in 14h. The catalysts were simple in its preparation, stable during the cellulose hydrolysis in addition to repeatedly without a significant loss of its catalytic activity. © 2014 Taiwan Institute of Chemical Engineers.

Nevzorova O.,Kharkiv National University of Radioelectronics | Arous K.,Kharkiv National University of Radioelectronics | Hailan A.,Thiqar University
2015 2nd International Scientific-Practical Conference Problems of Infocommunications Science and Technology, PIC S and T 2015 - Conference Proceedings | Year: 2015

In this paper the flow-based model of multicast routing was researched. To improve the scalability of the network the hierarchical approach of the network is used because usage of centralized schemes is very resource-intensive. Due to disagreement of solutions obtained on routers and thus appearance of the link overloading and the subsequent package lost we proposed to use the goal coordination method. The usage of this method allows distributing flows through links without its overloading and improving quality of service and increasing the efficiency of network management. © 2015 Kharkiv National University of Radioelectronics.

Mushatet K.S.,Thiqar University
2010 14th International Heat Transfer Conference, IHTC 14 | Year: 2010

In this paper, the turbulent natural convection heat transfer and fluid flow inside a square enclosure having two conducting solid baffles has been numerically investigated. Fully elliptic Navier-Stockes and energy equations are disrectized using finite volume method along with a staggered grid techniques. The resulting algebraic equations were solved by using semi-implicit line by line Guase elimination scheme. The effect of turbulence was incorporated to treat the regions near the walls. The flow and thermal fields are investigated for different parameters such as the relative baffles height, Rayleigh number and the distance between baffles. The conducted results indicated that the resulting vortices are decreased in number and elongated with the decrease of the dimensionless relative baffle heights. Also the results show that the rate of heat transfer is increased with the increase of Ra especially for the region near the baffles. © 2010 by ASME.

Lemeshko O.,Kharkiv National University of Radioelectronics | Nevzorova O.,Kharkiv National University of Radioelectronics | Hailan A.,Thiqar University
2014 1st International Scientific-Practical Conference Problems of Infocommunications Science and Technology, PIC S and T 2014 - Conference Proceedings | Year: 2014

To avoid overload of links, as well as packet loss in the network uses the coordination method. This method is based on the possibility of converting the original minimization problem in a simpler maximization problem and the solution of this problem using a two-level iterative computational structure. In this paper the analysis of convergence of the two-level hierarchical routing method with coordination is given. © 2014 IEEE.

Mushatet K.S.,Thiqar University
2011 IEEE 3rd International Conference on Communication Software and Networks, ICCSN 2011 | Year: 2011

In this paper, a computational investigation has been performed to analyze the turbulent flow characteristics inside a channel backward facing step under an inclined impingement cooling. The impinging jets were inclined towards the upstream cross flow and the angle of inclination was varied from 30 to 90. The effect of an inclination angle, the size of slot jets and the contraction ratio on the flow and thermal field was examined. The governing elliptic Navier-Stockes, energy and turbulence model equations were discretised by using a finite volume method. The k-ε model was used to model the turbulence. A computer program was developed to solve these equations by using the SIMPLE algorithm with a staggered grid technique. The aim of this paper is to show how the inclined impingement cooling inside a channel backward facing can represent a significant factor to enhance the rate of heat transfer and producing complex flow field features. The computed results show that the size and strength of recirculation regions are increased as angle of inclination increases. Such increase is also found with increasing the contraction ratio (SR). However this effect seems to be little compared with angle of inclination. The local rate of heat transfer is enhanced as the angle of inclination increases. The validation of the present scheme is performed through comparison with available published results. © 2011 IEEE.

PubMed | Sindh Agriculture University, ThiQar University and Huazhong University of Science and Technology
Type: | Journal: Journal of environmental management | Year: 2016

In order to maximize the biogas production from thickened waste activated sludge (TWAS), co-digestion of TWAS and rice straw (RS) was studied and the application of thermal/thermo-alkaline and NaOH/H2O2 to TWAS and RS, respectively, was evaluated. The batch experiments were conducted at three different TWAS/RS (volume basis) ratios of 1:3, 1:1 and 3:1, respectively. Furthermore, the modified Gompertz model was introduced to predict the biogas yield and evaluate the kinetic parameters. The highest biogas production (409.2L/kg VSadded) was achieved from co-digestion of TWASthermo-alkaline and RSNaOH at mixing ratio of 1:1, which is greater by 42.2% and 5.9% than that of digesting TWASthermo-alkaline, and RSNaOH alone, respectively. The highest VS removal rate was obtained from the co-digestion of TWASthermo-alkaline and RSNaOH at mixing ratio of 1:3, which is greater by 55.8% and 14.0% than those of mono-digestion. The modified Gompertz model (R(2): 0.993-0.998 and 0.993-0.999 for mono- and co-digestions, respectively) showed a good fit to the experimental results and the estimated parameters indicating that the pretreatments and co-digestion of substrates markedly improved the biogas production rate.

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