Pengaruh Ion Kromium(iii) pada Ekstraksi Ion Tembaga(ii) Menggunakan Emulsi Kerosen dengan 1-fenil-3-metil-4-benzoil-5-pirazolon sebagai Pembawa Kation

The influence of chromium(III) ion on copper(II) ion extraction using kerosene emulsion with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (HPMBP) as a cation carrier was investigated. The optimum condition for copper(II) extraction were as follows: concentration of mixed surfactant (span 80+span 20) was 5%, volume ratio of kerosene and internal phase was 1, concentration of HPMBP was 0.025 M, concentration of HCl was 1 M, volume ratio of emulsion and external phase was 0.143. The results showed that the extraction of copper(II) ion was selective to chromium(III) ion, relatively. The result also showed that the presence of 500 ppm chromium(III) ion decrease the percentage of copper(II) ion extraction from 98.6 to 91.0

Ab-initio study of the bandgap engineering of Al(1-x)Ga(x)N for optoelectronic applications

A theoretical study of Al(1-x)Ga(x)N, based on full-potential linearized augmented plane wave method, is used to investigate the variations in the bandgap, optical properties and non-linear behavior of the compound with the variation of Ga concentration. It is found that the bandgap decreases with the increase of Ga in Al(1-x)Ga(x)N. A maximum value of 5.5 eV is determined for the bandgap of pure AlN which reaches to minimum value of 3.0 eV when Al is completely replaced by Ga. The static index of refraction and dielectric constant decreases with the increase in bandgap of the material, assigning a high index of refraction to pure GaN when compared to pure AlN. The refractive index drops below 1 for photon energies larger than 14 eV results group velocity of the incident radiation higher than the vacuum velocity of light. This astonishing result shows that at higher energies the optical properties of the material shifts from linear to non-linear. Furthermore, frequency dependent reflectivity and absorption coefficients show that peak value of the absorption coefficient and reflectivity shifts towards lower energy in the UV spectrum with the increase in Ga concentration. This comprehensive theoretical study of the optoelectronic properties of the alloys is presented for the first time which predicts that the material can be effectively used in the optical devices working in the visible and UV spectrum.Comment: 18 pages, 7 figure

A Transitivity Analysis of Male and Female Students\u27 Final Draft of Critical Responses Paragraph to Literature

This study aims at investigating the realization of transitivity particularly process, participant and circumstance types realized in male and female students\u27 final draft of critical response paragraph to literature. A descriptive qualitative method was employed in analyzing and interpreting the whole data. Furthermore, eight students\u27 final draft of critical response paragraph to literature which were categorized into male and female students\u27 critical response paragraph. The findings showed that (1) most of the male and female students were able to realize the transitivity in which the transitivity was realized through the clauses that construct meaning of every single text. (2) Most dominant process realized in eight texts were material process, while actor and goal became the most dominant participants realized and circumstance of location became the most dominant circumstance realized in every single text. However, male students were tend to use the material process in their texts. This study concludes that even though the text were categorized into male and female students\u27 text, most of the text had realized correctly transitivity while both male and female students\u27 final draft of critical response paragraph to literature, material process dominantly emerged in the text. Finally, this study suggests English teachers and lecturers to refer the transitivity as a method which can be applied to check whether the students had correctly written critical response or not

Pengaruh Kadar Serbuk Gergaji dalam Proses Bioremediasi Tanah Tercemar Minyak

Bioremediation is one of the most cost-effective and environmentally friendly methods to remediate many different types of waste materials widely used by many private and public entities. This research was conducted to determine the influence rates of sawdust in the bioremediation process of petroleum contaminated soil by using laboratory methods, in combination with the addition of fertilizer as sources of nitrogen. This research was conducted based on the 100:5:1 of C:N:P ratios, respectively. Test parameters needed to knowing the optimal condition in remediation were pH, moisture content and temperature. Results show the Total Petroleum Hydrocarbon (TPH) was degraded until 44% for the addition of 500 grams sawdust size 0.2 cm, 33% for the addition of 750 grams sawdust size 3 cm and 20% without any treatment within around two months. The addition of sawdust and fertilizer has increased the efficiency of TPH degradation and obtained positive relationship for the addition of fertilizer to the level of TPH degradation

Ultrasonic Activation of Suzuki and Hiyama Cross-Coupling Reactions Catalyzed by Palladium

Abstract The coupling reaction of aryl bromide and aryl boronic acid in water/DMF as solvent was studied using a palladium-complex as a catalyst in the presence of ultrasound at room temperature. The effect on the reaction of a base and a solvent was also studied with and without ultrasound and was found to increase the speed of the reaction. In this regard, we propose reaction mechanisms that could explain the results obtained

‘They Called Them Communists Then … What D'You Call ‘Em Now? … Insurgents?’. Narratives of British Military Expatriates in the Context of the New Imperialism

This paper addresses the question of the extent to which the colonial past provides material for contemporary actors' understanding of difference. The research from which the paper is drawn involved interview and ethnographic work in three largely white working-class estates in an English provincial city. For this paper we focus on ten life-history interviews with older participants who had spent some time abroad in the British military. Our analysis adopts a postcolonial framework because research participants' current constructions of an amorphous 'Other' (labelled variously as black people, immigrants, foreigners, asylum-seekers or Muslims) reveal strong continuities with discourses deployed by the same individuals to narrate their past experiences of living and working as either military expatriates or spouses during British colonial rule. Theoretically, the paper engages with the work of Frantz Fanon and Edward Said. In keeping with a postcolonial approach, we work against essentialised notions of identity based on 'race' or class. Although we establish continuity between white working-class military emigration in the past and contemporary racialised discourses, we argue that the latter are not class-specific, being as much the creations of the middle-class media and political elite