Thickness Effect on Some Physical Properties of RF Sputtered ZnTe Thin Films for Potential Photovoltaic Applications

Zinc telluride thin films with different thicknesses were grown onto glass substrates by the rf magnetron sputtering technique, using time as a variable growth parameter. All other deposition process parameters were kept constant. The deposited thin films with thickness from 75 to 460 nm were characterized using X-ray diffraction, electron microscopy, atomic force microscopy, ellipsometry, and UV-Vis spectroscopy, to evaluate their structures, surface morphology, topology, and optical properties. It was found out that the deposition time increase leads to a larger growth rate. This determines significant changes on the ZnTe thin film structures and their surface morphology. Characteristic surface metrology parameter values varied, and the surface texture evolved with the thickness increase. Optical bandgap energy values slightly decreased as the thickness increased, while the mean grains radius remained almost constant at ~9 nm, and the surface to volume ratio of the films decreased by two orders of magnitude. This study is the first (to our knowledge) that thoroughly considered the correlation of film thickness with ZnTe structuring and surface morphology characteristic parameters. It adds value to the existing knowledge regarding ZnTe thin film fabrication, for various applications in electronic and optoelectronic devices, including photovoltaics.

Effect of milling treatment and additives on the morphology evolution of α-alumina from a commercial boehmite precursor

Because calcined alpha alumina (α-Al2O3) inherits the morphology characteristic of milled precursors, it is expected that the α-Al2O3 morphology could be improved by controlling the precursor morphology through the use of different milling processes. The microstructure evolution of the boehmite precursor under different milling treatments (planetary ball milling [PBM] and high-energy ball milling [HEBM]) and its influence on the microstructure of as-synthesized α-Al2O3 were investigated. The experimental results indicate that HEBM has a stronger modification effect in crystallinity, particle size and dispersibility of the boehmite precursor than PBM, which is of great importance to inhibit the formation of the typical worm-like structure of α-Al2O3. The microstructure of α-Al2O3 was further improved by the introduction of NH4BF4, NH4F and NH4Cl as additives. In particular, polygon-like α-Al2O3 particles with a size of 0.5 μm and a good dispersibility were prepared by calcination of the precursor with 30 h of HEBM and 20 wt.% NH4BF4.

Screening of Antibacterial Metabolites from Marine Soil, Kodiyampaiayam, Tamilnadu

The marine environment is a rich resource for isolating exploited microorganisms. In recent years, antibiotics have become important in this study of new antibiotics that show antiviral, anticoagulant and cardiac properties. Soil samples were collected from different area and isolated the bacterial colonies were separately streaking in agar plates (KP1, KP3, KP6, KP7 and KP9). The bacteria were done by morphology characteristic after that bacterial crude extract was taken separately. The crude extract was used in antibacterial activity against human pathogenic bacteria. There KP 7 and KP 9 havethe highest activity in B. subtilis and S. pyogenes rest of the samples also had activity comparing to these samples (KP 7 and KP 9) is highest zone inhibition developing. The marine sediment having so many microbes and secondary metabolites, therefore,the most useful drug development..

Analisis Serapan Hara Nitrogen dan Fosfor Tanaman Kedelai

Experimental research will be executed on farm of rice field sample in BPP Palaguna at Wajo Regency. Obstetrical nutrients Analysis of crop and soil will be done in soil Fertility Laboratory, soil sciences department of Faperta Unhas. This Research aim to analyze the ability of nutrients absorption of soy and maize with the mulch application on rice field rainfed. Research will be done/conducted by using Factorial Device in Group ( RDG). First Factor that is crop type with three treatment level that is L1 = Soy; L2 = Maize; and L3 = Maize + Soy. Second Factor is with mulch (M1) and without mulch (M0). Every treatment unit repeated by 3 times, so there are 18 plot, added a plot which is not cultivated as control for the perception of dynamics of Nitrogen (N) and Phosphorous (P) without palawija cultivation. Reason of the crop election for example because both types of the crop have their own system of root and different morphology characteristic which their possibility will influence the ability of conservation N. Result of analysis indicate that ability of absorption of N and P of maize and soy is better with the mulch application on rice field rainfed

Isolasi Bakteri Selulolitik dari Limbah Kulit Pisang

Cellulose can be found in whole parts of plants. Cellulose can be degraded by cellulose enzyme. Cellulose enzyme is produced by cellulolytic bacteria which has ability to degrade the cellulose and fiber. Cellulose enzyme is extremely important in industry sector. This research aims to isolate the cellulosic bacteria of peel waste of Banana in Sorong, West Papua. This research used isolation and purification method by using 1 gram of Banana peel. It was isolated in CMC (Carboxymethyl cellulose) selective media and morphology characteristic test using 400X-1000X microscope and zone index test. The result showed that the cellulosic ability was found in isolate B with pure zone index 3mm and the smallest pure zone index was in isolate H with pure zone index 0,8 mm. while, the isolate C had zone pure index 1,5 mm, isolate D 1,625 mm, isolate E 1 mm, isolate F 0,714mm, and isolate G 2 mm.