Archives-October 2014

The field of SLA is relatively new, but different classifications have been suggested for its development (Mitchell & Myles, 2004). Indeed, there is an anonymous agreement that the establishment of SLA as a field of enquiry goes back to 1950s- 1960s (Schachter, 1998). As for the classification proposed by Ellis (2009), one development dealt with the scope of the field of enquiry. While much of the earlier work had focused on the linguistic, and especially the grammatical properties of learner language, and was psycholinguistic in orientation, later work attended to the pragmatic aspects of learner language and increasingly, employed a sociolinguistic perspective. A second development concerned the increasing attention paid by SLA researchers to linguistic theory, in particular the theory of language associated with Chomsky's model of grammar: Universal Grammar. A third development was the marked increase in theory-led research. Whereas much of the earlier research was of the research-then-theory kind, typically consisting of the collection and analysis of samples of learner language, later research was increasingly theory-led and experimental in style.

The kinetics of oxidation of cyclohexanol by PDC has been studied in non-aqueous medium. In this oxidation Cr(VI) is working as two-electron oxidizing agent. The reaction is first order with respect to each [oxidant], [TsOH] and [cyclohexanol]. The reaction is catalyzed by hydrogen ions. Low dielectric constant of the medium favors the reactivity. The observed experimental data have been rationalized as follows: the formation of dichromate ester in a fast pre equilibrium step and then decomposition of the ester in slow step via a compact transition state leading to the product, cyclohexanone.

The kinetics of oxidation of some para-substituted benzyl alcohols by PDC have been studied in DMSO spectrophotometrically acidified with TsOH. From good linear Eyring plots ?H# and ?S# are calculated. The reaction has unit dependence on each [PDC], [H+] and [Alcohol]. Electron-releasing substituent accelerates the reaction, whereas electron-withdrawing groups retard the reaction, and the rate data obey Hammett's relationship. PDC is acting as two-electron transfer oxidant. A mechanism implicating the prior acid-catalyzed formation of dichromate ester followed by cyclic intermediate is proposed.

In this paper we report simulation and experimental characterization of microstrip antenna that employs silver nanofilm as radiating patch. The bulk silver is deposited to a thickness of 30 nm using physical vapor deposition system. In this work non-contacting feed aperture coupled patch antenna is used in order to avoid soldering problem between nanofilm (ultrathin) and bulk copper feed thickness of 17 micron. The experimental result of fabricated nanofilm antenna shows wide bandwidth response over bulk patch antenna. Using nanofilm, an optimum bandwidth of 12% is obtained which is 50% higher than bulk patch antenna. The nanofilm antenna resonates around 6.5 GHz finds application in ‘C’ band frequency.

Electrocoagulation is an emerging water treatment technology that has been applied successfully to treat various wastewaters such as potable water, urban wastewater, heavy metal laden wastewater, restaurant wastewater, and colored water. Electrocoagulation offers possibility of anodic oxidation and in situ generation of adsorbents (such as hydrous ferric oxides, hydroxides of aluminum) on which As(III) might be oxidized to As(V) gets adsorbed on to the metal hydroxides (HFO) generated. Therefore, electrocoagulation would be a better choice for arsenic removal from water. In the present study an attempt has been done to develop a simple process employing electrocoagulation with iron electrodes and separation of HFO has been achieved by cloth filtration. Arsenic laden water is passed through a double layer cotton cloth in 2 L volume beaker at flow rate 44ml/min with current 0.2 ampere at pH 7.0. Results show that arsenic levels below 50 ?g/L would e achieved which is drinking water standard in India and Bangladesh.

Palani hill temple is one of the most important pilgrim centres for south Indian people. It is located in western part of dindigul district of tamilnadu and also it is situated at foot of kodaikanal hills. The temple attracts lacks and lacks people throughout the year. This temple and town are mainly depending upon Palar-Porundalar river dam for drinking water. The physico-chemical studies such as electrical conductivity, PH, Total dissolved salts, Total hardness and total alkalinity for this dam was analysed. All the physical parameters were below the permissible limit of WHO. For this analysis ten places were chosen. All the ten samples were free from CO2 which indicates this water was free from organic wastes and effluents from industries. Total hardness and total alkalinity of all the samples were below the permissible limit of WHO. Therefore this is water recommended for drinking and washing.

This study involves the preparation and characterization of hydrothermally grown zinc oxide (ZnO) nanorods. Zinc acetate dihydrate, ethanol and de-ionized water were used to prepare seed layer. Zinc nitrate and hexamethylenetetramine solution were used for growth of ZnO nanorods. The ZnO nanorods were grown for 5 hours at three different temperatures of 80°C, 90°C and 100°C and annealed at 500°C in air atmosphere. Nanorod growth temperatures are varied and the corresponding changes in structural, morphological, optical and photoluminescence properties were reported. The ZnO nanorods were investigated by XRD, SEM, UV and PL studies.

Celecoxib, a selective COX-2 inhibitor, exhibits poor water solubility, dissolution and flow properties. Thus, the aim of the present study was to improve the solubility and dissolution rate of Celecoxib by preparing microparticle by Freeze drying technique. Celecoxib microparticle containing different ratio of drug and ?-cyclodextrin were manufactured by Freeze drying using Isopropyl alcohol as solvent to enhance solubility and dissolution rate. The prepared microparticle containing different ratio of drug and polymer were evaluated for in vitro dissolution and solubility. The prepared formulations were characterized by scanning electron microscopy, differential scanning calorimeter, X-ray diffraction and Fourier transform infrared spectroscopy. Dissolution profile of the Freeze dried microparticle was compared with its physical mixture and pure sample. Freeze dried microparticle exhibited decreased crystallinity. The solubility and dissolution of the microparticle containing different ratio of drug and ?-cyclodextrin were significantly improved compared with its physical mixture and pure sample of Celecoxib. Dissolution of microparticle containing 3:1 w/w (FD 3) showed higher % release i.e. 98.6 % in 30 min compared to other ratio of microparticle. Consequently, hence, from the above result it can be concluded that Freeze dried microparticle of Celecoxib is a useful technique to improve the solubility and dissolution of poorly water soluble drug like Celecoxib.

Good quality single crystals of pure p-hydroxy acetophenone (PHAP) and Cd+ doped p-hydroxy acetophenone have been successfully grown from aqueous solution by slow evaporation technique. The lattice parameters of these crystals are found to be for pure PHAP and Cd+ doped PHAP using X-ray diffraction method. The functional groups of the materials are confirmed qualitatively by FTIR spectral analysis. Optical absorption studies on these samples reveal the minimum absorption region to be well suited for NLO applications. Thermal analysis have been carried out on the compounds confirm the samples are thermal stable up to 163ºC.

Lack of social and emotional skills is perhaps the most undermining problem that students with hearing impairments confront; by taking that into consideration, the goal of the present study is to appraise the effectiveness of Social-Emotional Learning (SEL) on the emotions management of students with hearing loss studying in normal schools. This study is based on an experimental method and a pre-test and post-test design has been applied to the control group. To that end, 30 male and female hearing-impaired students from junior and senior high schools covered by Tehran’s Department of Exceptional Children Education were handpicked through multistage sampling and those who met the research criteria were randomly placed in two control and experimental groups and after a pretest, the social-emotional learning program was taught to the experimental group in 12 sessions. To measure the emotions management, Schutte Emotional Intelligence Questionnaire was used. The findings of the present research display a significant difference (p< 0/0001) between the control and experimental groups with regard to emotions management. The conclusion can be drawn that the Social-Emotional Learning program is efficient in the emotions management of students with hearing impairments in regular schools.