Preparation of Activated Carbon from low cost Precursors ab 79 € als Taschenbuch: And its Use for the Wastewater Treatment. Aus dem Bereich: Bücher, Wissenschaft, Chemie,
Preparation of Activated Carbon from low cost Precursors ab 79 EURO And its Use for the Wastewater Treatment
The wide band gap semiconductors SiC and GaN have shown great potential for use in high-temperature, high-power and high-frequency electronic devices as well as short-wavelength optical devices. However, the lack of large-area and low-cost substrates hindered their development seriously. Thus, the heteroepitaxy of SiC and GaN on silicon substrates is highly desirable for the Si-based electronic industry. In this study, we investigated the epitaxy of 3C-SiC and hexagonal GaN on silicon substrates and related devices. High quality 3C-SiC epilayers were deposited with trimethylsilane and silane/propane precursors, respectively. Inversion- mode n-channel 3C-SiC MOSFET devices with high channel mobility have been successfully fabricated. For GaN growth, AlGaN/GaN heterostructures were grown on 100 mm diameter Si(111) substrates without cracking using a high-temperature AlN buffer layer and a 3C-SiC buffer layer. In addition, the growth of hexagonal GaN on Si(100) substrates was demonstrated for the first time using a sputtered AlN buffer layer followed by a MOCVD grown AlN buffer layer.
Low cost agricultural waste material and animal bones were utilized for the preparation of activated carbon. Industrial spent carbon was also regenerated. The carbon samples were activated chemically and by thermal means (400-1000°C). The samples were characterized by surface area (BET, DR, BJH, Langmuir) with pore volume, FTIR, XRD, SEM and EDS. The rate of adsorption of dyes on the carbon samples was high in the initial fifteen seconds and then declined due to its diffusion in to the micropores. Negative values of entropy of activation ( S) of the dyes adsorption reflected the affinity of the dye molecules towards the carbon surface which were found to decrease with the increase in adsorption temperature. The linear plots of Bangham and intraparticle diffusion models showed that the adsorption of dye on the carbon surface is a diffusion controlled process. The Freundlich, Langmuir and DR models were used to estimate the adsorption parameters. The best fit of the isotherms, found from the correlation coefficients (r2) were in the sequence: DR Langmuir Freundlich.
The present work planned to synthesize NiO/PPy and NiO/PANI thin films by electrodeposition and chemical bath deposition respectively. In conclusion, we could successfully demonstrate: (i) Cost-effective one step deposition of NiO thin films at room temperature from low-cost precursors. (ii) Electrochemically stable NiO sample with moderate colouration efficiency. (iii) NiO-PPY composites with excellent stability and fast switching response. (iv) NiO-PANI composites with higher colouration efficiency, faster response time, stable and marvelous range of colours. (v) It is concluded that the strong co-ordinate bonding between NiO and organic polymer (PPY and PANI) resulted into the marked improvement in their EC performance. (vi) This strategy would also pave the novel way to synthesize variety of combination of the oxide-polymer composites (via combination of cost-effective ED and CBD methods) on large areas, suitable for building facades as smart windows. This route would offer a smarter and enabling way for energy efficient buildings, thereby helping conservation of energy, the urgently needed technology to override energy crisis in India.
Over the last two decades, the use of cellulosic fibers as reinforcing elements in polymeric matrix has been the subject of a good deal of work. Essential reasons for this is the possibility of replacing conventional fibers such as glass by natural cellulosic fibers in reinforced composites due to the abundance, renewable, low cost and eco-friendly nature of cellulose. The original work of the candidate presented in book is undertaken with a view to accomplish technological through harnessing nanotechnology in development of novel precursors for use in different applications especially in green synthesis of nanostructural materials. The as prepared cellulose nanowhiskers (CNW) are chemically modified through grafting and etherification and the onset of this on their ability to form nanocomposites are investigated. Utilization of this newly prepared nanocellulosics as precursors in green synthesis of metal nanoparticles are studied. Also studied are the applications of CNW in textile wet processing and other disciplines. Moreover, optimization of the potential properties of stimuli responsive hydrogels nanocomposites will be addressed in terms of in-vitro drug release.
High Quality Content by WIKIPEDIA articles! Nanofiltration is a relatively recent membrane filtration process used most often with low total dissolved solids water such as surface water and fresh groundwater, with the purpose of softening (polyvalent cation removal) and removal of disinfection by-product precursors such as natural organic matter and synthetic organic matter.Nanofiltration is also becoming more widely used in food processing applications such as dairy, for simultaneous concentration and partial (monovalent ion) demineralisation.Nanofiltration (NF) is a cross-flow filtration technology which ranges somewhere between ultrafiltration (UF) and reverse osmosis (RO). The nominal pore size of the membrane is typically below 100 nanometres, thus Nanofiltration. Nanofilter membranes are typically rated by molecular weight cut-off (MWCO) rather than nominal pore size. The transmembrane pressure (pressure drop across the membrane) required is considerably lower than the one used for RO, reducing the operating cost significantly. However, NF membranes are still subject to scaling and fouling and often modifiers such as anti-scalants are required for use.
Fluorescent carbon nanoparticles (CNPs) are a new class of carbon nanomaterials and have demonstrated excellent optical properties, good biocompatibility, great aqueous solubility, low cost, simple synthesis, etc. Since their discovery, various synthesis methods using different precursors have been developed, and are mainly classified as top-down and bottom-up approaches. The contact angle measurements revealed that wettability of plain chitosan film reduced due to addition of carbon nanoparticles. It was found that, impregnation of carbon dots into chitosan film resulted in an almost seven fold decrease in the water absorption capacity of the film. The equilibrium moisture uptake(EMU) data of plain chitosan and CQD-loaded chitosan films were interpreted by GAB isotherm and related parameters were also evaluated. Finally, the moisture permeation capacities of the plain Ch and Carbon dots loaded sample Ch/CNP was found to be 1758 and 956 g/m2 /day. In addition, Bovine serum albumin (BSA) adsorption was found 24.2 mg /m2 for plain sample while it decreased to 14.1 mg/m2 as CDs were incorporated into film matrix. The anti-oxidant property was evaluated in terms of % scavenging of DPPH, SO and Hydroxyl radicals. It was observed that for all the free radicals, % scavenging increased with increase in CDs contents in the films.furthermore we load the oxytetracycline drug in nanocomposites film for wound healing and drug delivery.
A simple and low-cost solution combustion method was used to prepare Eu3+and Sm3+ (1-11 mol%) doped Mg2SiO4 nanophosphors at 350 oC using metal nitrates as precursors and ODH as fuel. The final products were well characterized by Powder X-ray Diffraction, Fourier Transform Infrared spectroscopy, scanning electron microscopy and DRS. The PXRD patterns of the as-formed products show single orthorhombic phase. The crystallite size was estimated using Scherrer's method and found to be in the range 20-25 nm. The effect of Eu3+ and Sm3+ cations on the luminescence properties of Mg2SiO4:RE3+ nanoparticles were understood from the luminescence studies. The Commission International de I'E' clairage (CIE) chromaticity coordinates were calculated from emission spectra, the values (x,y) were located in red region. The correlated color temperature (CCT) was calculated and found that the prepared phosphor is useful for red light-emitting devices.