ISSN: 1817-2695

Volume 37, Issue 2

Volume 37, Issue 2, Spring 2011, Page 1-112


Numerical prediction to study the effect of pentroof chamber on the

Sadoun Fahad dakhil

Journal of Basrah Researches (Sciences), Volume 37, Issue 2, Pages 1-10

This paper describes a new method for estimating the induction swirl intensity by means of the numerical simulation of gas flow in the intake port and cylinder to optimize combustion chamber design.
The optimization procedure adopted in the present investigation is based on GENERIC ALGORITHIMS and allows different fitness functions to be simultaneously maximized. The parameters to be optimized are related to geometric feature shape of the combustion chamber. The evaluation phase of GENERIC ALGORITHIMS was performed by simultaneity behavior of each design with modified version of FLUENT code 6.2.
The present work represents Direct injection spark ignition engine with different combustion chamber design to get optimum swirl ratio with different engine speed. The study of the chamber angle variation is to show the change in air jet value around inlet valves and then design optimum angle which gets uniform annular jet around each intake valve to give as a result high swirl ratio. Good results are obtained at engine speed 2500 rpm with pentroof angle 15º for both sides. These results give good agreement with experimental result by Ref [1], where he used single inlet valve chamber.

Reactive Ion Etching (RIE) for Micro and Nanogap Fabrication

N. M. AHMED; Th. S. DHAHI; U. HASHIM

Journal of Basrah Researches (Sciences), Volume 37, Issue 2, Pages 11-20

To understand the important relationship between the biosensor and micro and nanostructures we introduce this proposal about the fabrication of micro and nanostructure by using one of the most important dry etching processes in micro and nanostructures, reactive ion etching (IC-RIE) has been applied and developed as a method for etching micro and nanogap semiconductors. PolySi material is used to fabricate micro and nanogap structure and gold as electrodes. The fabrication and preparation methods to fabricate micro and nanogaps using RIE properties are discussed along with their advantages towards the nanotechnology and biodetection. In this study, 2 masks design are proposed. The first mask is the lateral micro and nanogap and the second mask is for gold pad electrode pattern. Lateral micro and nanogaps are introduced in the fabrication process using polysilicon and gold as an electrode. Conventional photolithography and dry etching techniques are used to fabricate these micro and nanogaps based on the standard CMOS technology. As a result we need to deposit Al layer over the polysilicon semiconductor before coating a photoresist to protect the polysilicon layer during the etching (IC-RIE) for using the Al material as a hard mask. The requirement time to etch 1μm polysilicon layer completely by using IC-RIE to fabricate the micro and nanogap structure it takes approximately 40sec. These results are better than those using wet anisotropic etching techniques.

A linear Programming Formulation of

FATHALLAH FADHIL KHALAF AL-ABDULHAMEED

Journal of Basrah Researches (Sciences), Volume 37, Issue 2, Pages 21-26

In this work, the problem of job-machine assignment was formulated as a linear programming (LP) models and then solved by the simplex method. Three case studies were involved in this study to cover all kinds of problems may be faced. To verify the results of the LP models, these problems also solved using transportation algorithm and has been found that the LP model is more efficient for solving the assignment problems.

Online Tuning of Stator Resistance in DTC Drive

Majid A. Alwan

Journal of Basrah Researches (Sciences), Volume 37, Issue 2, Pages 27-41

Direct torque control (DTC) needs the stator resistance of the induction motor for the estimation of stator flux. The variation of stator resistance due to temperature and stator frequency changes will greatly affect the performance of DTC drive run at low speed. In this paper, a method for the tuning of changes in stator resistance during the operation of the machine is proposed. The tuning method is based on wavenet theory. To show the ability of the proposed method, a PI stator resistance tuner is presented. The tuners observe the magnitude of stator flux of the machine to detect the changes in stator resistance. The performances of the two methods are compared using Matlab/Simulink simulation results. The simulation results show that the proposed wavenet stator resistance tuner efficiently improves the DTC performance, superior to the PI stator resistance tuner.

A new design of a single slop double- basin solar still(SSDBS)

Aqeel Y. Hashim

Journal of Basrah Researches (Sciences), Volume 37, Issue 2, Pages 42-49

A new type of a single slope double- basin solar still have been designed and manufactured; in order to compare its productivity with that of a single basin solar still, an experimental investigation was carried out on two single slope solar stills with different basin under actual field conditions; where the first still is conventional solar still with horizontal basin of 0.25m2 while the basin of the second still (the new design) has two partitions; horizontal basin of 0.1m2 and vertical basin of 0.15m2. From the experimental results, it has been observed that there is significant enhancement in daily output due to the basin deviation on a clear day. The main advantages of the vertical partition of the basin are that the latent heat of vapor condensing over the inner surface of the still is utilized in heating the water in the vertical partition of the basin which leads to store the hot water for the continuity of vapor at night , also the vertical partition of the basin helps to concentrate the sun ray on it by any type of external reflector to increase the productivity.

Optical properties of Pb1-xSnxSe epitaxial layers on (100)KCl, NaCl

Mohammad M. Ali; Seif M. Meshari

Journal of Basrah Researches (Sciences), Volume 37, Issue 2, Pages 50-56

Epitaxial Pb1-xSnxSe layers were grown onto cleaved and polished (100) KCl,(100) NaCl and (111)CaF2 substrates in a high vacuum system by means of the hot-wall-epitaxy (HWE) method. The source temperature of Pb1-xSnxSe ~ 570 oC and substrates temperature are ranging from 200 to 275 oC by increasing step 25 oC, growth rate (1.51-2.4 μm/h). The optical absorption constant is determined using FTIR in the (0.496-0.062) eV photon-energy range at room temperature. The data have been analyzed to estimate the forbidden bandwidth.

Study of the linear and nonlinear optical properties of Neutral Red doped Polyvinylpyrrolidone film

Alaa Yassin Al-Ahmad; Hussain A.Badran; Mohammad Fadhil Al-Mudhaffer

Journal of Basrah Researches (Sciences), Volume 37, Issue 2, Pages 57-63

Measurement calculations were carried out to determine the linear optical constants such as extinction coefficient, refractive index, average excitation energy and dispersion energy for the 3- amino-7-dimethylamino-2-methyl phenazine (Neutral red NR) doped Polyvinylpyrrolidone (PVP) film. Further the optical nonlinearities of Neutral Red : Polyvinylpyrrolidone solution have been investigated by Z-scan technique with CW laser at 657.2 nm The nonlinear refractive index and absorption coefficient are found to be in the order of - 1.91 ×10-9cm2/Watt , 1.13×10-4 cm/Watt, respectively .These results show that the ample has potential application in nonlinear optics.

The Preparation, Characterization and the Study of the Linear Optical Properties of a New Azo

Hasanain A S. A Majeed; Alaa Yassin Al-Ahmad; Kawkab Ali Hussain

Journal of Basrah Researches (Sciences), Volume 37, Issue 2, Pages 64-73

Azo dye was prepared from 4,4-diaminodiphenyl sulfone with chromotrpic acid by fox method. Azo dye was identified via IR-Infrared spectrophotometer, UV-visible spectroscopy and elemental analysis (CHN). The basic optical properties of azo dye have been studied at room temperature. The optical energy gap was estimated from the absorption coefficient values using Taue’s procedure. The values of the static refractive index , the static dielectric constant , oscillator energy , dispersion energy , the moments of optical dispersion spectra, and the band gap energy have been determined by the Wimple-Didomenico method .

Two-Way Multivariate Repeated Measurements Model For Between-Units Factors With Two Covariates

Assist.Prof.Dr.Abdul Hussein Saber AL-Mouel and Atyaf Sally Fakhir

Journal of Basrah Researches (Sciences), Volume 37, Issue 2, Pages 74-86

This research is devoted to study of two-way Multivariate repeated measurements analysis of covariance model (MRM ANCOVA), which contains two between-units factors (factor A and factor B), and two covariates (Z_1,Z_2 ) .For this model the two covariates are time-independent, that is measured only once. The test statistics of various hypotheses on between-units factors and the interaction between them are given, and includes the application of the theoretical part. It studies the effect of some internal and external factors on blood parameters, which are available in the experiment during one year through nine months. The data are taken from Department of Biology, College of Education, University of Basrah. Then , the data are analyzed according to the our model

Synthesis , Identification and Study of Some New Schiff Bases as Inhibitors for Brass Corrosion

Mouayed Y. Kadhum

Journal of Basrah Researches (Sciences), Volume 37, Issue 2, Pages 87-112

Three Schiff bases were synthesized namely (4-dimethyl amino benzaldene – 3-amino benzoic acid ) , ( piperonaldene – 4-amino – 2-nitro toluene ) and (4-dimethyl amino benzaldene - 4-amino – 2-nitro toluene ) . These Schiff bases have been identified by microanalysis ( CHN ) , infrared , 1H-NMR , 13C-NMR and GC-Mass spectroscopy . The study also included the use of these Schiff bases as inhibitors for corrosion of brass in acidic media ( 0.5 M HCl ) . The rate of corrosion was determined by two methods ( electrochemical and weight loss methods ) . It was found agreement between them . Different studies such as ; the effect of temperature on the corrosion rate at ( 298 ˚K , 308 ˚K and 318 ˚K ) , measurement of some thermodynamic parameters ( corrosion current , activation energy and free energy ) , and comparison of inhibition effect for prepared Schiff bases with their primary amines were achieved . The results indicated that these Schiff bases inhibited the corrosion efficiently . Furthermore , antibacterial activity of prepared Schiff bases and standard inhibitor (AK3) was also studied on the two types of bacteria ,Staphylococcus aureus and Escherichia coli . It was found that the Schiff bases under study were considered inhibitors for bacterial growth with variation extents .