Archives-June... 

Four new cationic surfactants based on sulphonamide were synthesized. Their chemical structures were confirmed using, FTIR, H NMR spectroscopic analyses. The surface active properties of the synthesized surfactants were calculated from surface tension measurements at different temperatures .The performance of these surfactants as corrosion inhibitors for X-65 type carbon steel in oil wells formation water under H2S environment was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. The obtained results showed that the percentage inhibition efficiency (?%) was increased by increasing the inhibitor concentration until the critical micelle concentration (CMC) reached. Also, it was found that inhibition efficiency was increased by increasing both molecular size of the surfactant and introducing ethylene oxide units in the surfactant molecule. The data obtained from (EIS) was analyzed to model the corrosion inhibition process through equivalent circuit. Finally, the nature of the protective film formed on carbon steel surface was examined by SEM and EDX techniques.

The primary concern of this study was whether there is a relationship among teachers' feedback and type of class (task-based or traditional) ,feedback in education has got various types and fields ,but tutor's feedback to students errors was the researcher's concern.How the tutor corrected the learners in these two kinds of classes can show the researchrers and tutors the effects of feedbacks on learning and teaching and also communicating.To aim this,The researcher examined the students in two groups and examining the teachers' feedback to defining four types of learners errors (M orphosyntax , Semantic, Phonological, Lexical ).Task which was taught in TB class was ordering and matching . Using various sorts of tasks in order to improve students performance in real world (Skehan 1996a).The method which used to analysis data was be Chi-square.The results of the present study revealed that there was no significant relationship between type of class and tutor's feedback .

Background: During the embryonic development, a complex program defines the normal neural tube development, alteration in this process, results in Neural Tube Defects (NTD). Aim: The present study found the effects of progesterone, more than the physiological value in neural tube development of chick embryos. Materials and methods: 240 fertile, pathogen-free eggs, incubated at 37.50C and 75% relative humidity until the embryos reached stage ten of development. The eggs were divided into five equal groups. Statistical Analysis Used: None. Conclusions: Our study showed that progesterone at the ten and twenty times more than its physiological values caused NTDs.

The aim of the present paper is to obtain the distribution of mixed sum of two independent random variables with different probability density functions. One with probability density function defined in finite range and the other with probability density function defined in infinite range and associated with product of Srivastava’s polynomials and Aleph-function. We use the Laplace transform and its inverse to obtain our main result. The result obtained here is quite general in nature and is capable of yielding a large number of corresponding new and known results merely by specializing the parameters involved therein. To illustrate, some special cases of our main result are also given.

Electric discharge machining (EDM) is a non-traditional machining processes that involved a transient spark discharges through the fluid due to the potential difference between the electrode and the work piece. In this experiment, EDM process on mild steel workpiece was conducted EDM Die Sinking Neu-ar. The electrodes used were copper, brass and graphite. This project is to be conducted using Taguchi method L4 orthogonal array. The parameters to be studied are peak current (12A and 21A), discharge ON time (10µs and 45 µs) and pumping direction (B0 and B1). This research aims to study the factors that influencing the machining of different electrodes in electrical discharge machining (EDM) process. Surface roughness was measured using surface roughness tester (SJ-301). Material removal rate (MRR) and electrode wear ratio were determined based on weighting the workpiece and electrode using digital weight scale. Then, the result of the experiment was analyzed by using EXCEL. The higher material removal rate in the EDM machine, the better is the machining performance while the lower electrodes wear ratio in the EDM machine is the better and accurate performance characteristic. The results show that copper electrode gives higher material removal rate which is 0.411 g/min than brass and graphite. Brass electrode gives better surface finishing which is 15 ?m and graphite electrodes give the better electrode wear rate which is 0.53 among two electrodes. Key words: Electrical Discharge Machining, Surface Roughness, Material Removal Rate, Electrode Wear Ratio.

The mastery of writing skill is a crucial for ESL/EFL students. Scholars in the field of language teaching and learning have suggested so many strategies and methods to improve writing compositing. One of these methods is journal writing. However, whether the students actually realize that journal writing may improve a special kind of writing has not been explored. Therefore, the present study was conducted to investigate the effect of applying journal writing on the descriptive, reflective, and critical ability of EFL learners. The study included 80 male and female EFL learners of Hermes institute at the advanced level of language proficiency who were selected, and randomly assigned to experimental and control group. In the course of 10 sessions, the experimental group took the pretest and post test by which the teacher feedback and during which the treatment rubric were introduced. In control group, besides the pretest and posttest, they were provided with traditional writing with no treatment. Descriptive statistics and a paired sample t-test were utilized to analyze the data demonstrated that the two groups were significantly different regarding their writing ability. In order to compare the posttest of the three experimental groups while taking into account their initial differences on pretest (i.e. covariate) ANCOVA was administered. It was concluded that descriptive and reflective models of writing can lead to higher improvement in writing. In other words, the results of this study revealed that descriptive and reflective journal writing have positive effects on the learners’ writing achievements and provided opportunity for teachers to modify and revise their teaching performances in terms of allocating much time on the content of the learners’ writings to achieve the qualified teaching and learning.

Grievances or conflicts are part of industrial/ corporate scenario. In the working lives, employees occasionally have reasons to be uncomfortable, disappointed or aggrieved either about certain managerial decisions and practices or service conditions. The question then is whether this particular symptom or feeling is given any attention or is ignored altogether. What are the pros and cons of each of the approaches? The conflicts or disappointments cannot be eliminated but their expressions will contribute towards their reduction. Such expressions lead to adjustments and further improved organizational effectiveness. To a large extent, the approach to the problem will be governed by several variables such as the style of management, size of the enterprise, level of education of the workforce, technology of the plant and the extent of unionization of the work force.

The formalized theory of the identification of genotypes by their phenotypes in modern breeding technologies is offer. It erect on the mathematical model of the interaction "genotype-environment".

The paper explores the herding relationship between spot market and futures market by using two different herding measurements. Heavily traded constituents stocks of Taiwan electronic sector index and finance sector index are used to test the existence of herding. We also examine whether herding behavior has asymmetric reactions for up (bull) markets and down (bear) markets. Daily and 15-minute returns data covering Taiwan spot market and Taiwan futures market are analyzed. The results partly support the information cascade theory and rational asset pricing theory. Investors do herd temporarily but also trade rationally in a long period. Furthermore, daily and 15-minute data demonstrate the investors’ tendency toward herding is higher during market downstream.

In Wireless Sensor Networks, cluster head is the key technology where nodes or motes the information transmit it to the base station. The energy consumption in a wireless sensor network can be reduced by allowing only some nodes to communicate with the base station. One way to support efficient communication between sensors is to organize the network into multiple groups, called clusters, with each cluster electing one node as the head of cluster. To support scalability, nodes are often grouped mostly non-overlapping clusters. This paper proposes a new design of an efficient clustering in wireless sensor head which is based on two level clustering. In two levels clustering approach instead of sensor nodes sends the data to cluster heads directly, each node sends data to their cluster head and then sends data to the base station.