Purification Etc Research Articles

Non-magnetic adsorbent functionalized magnetism and spin filtering in a two-dimensional GaN monolayer

Exotic properties provided by the adsorption of non-magnetic Si atoms on a two-dimensional–GaN (2D–GaN) monolayer have been predicted using a generalized gradient approximation within density functional theory. This includes the occurrence of spin filtering, high magnetism and the continuous emission of electromagnetic radiation. A comprehensive ab-initio study of the structural, electronic, magnetic and optical properties of a 2D–GaN monolayer possessing several Si atoms as adsorbents has been performed. The semiconducting pure GaN monolayer was converted into its metallic analogue in several Si-adsorbed GaN monolayer systems. Along with the main strong absorption lying in the deep ultraviolet region near 5.5 eV observed in all of the Si-adsorbed 2D-GaN monolayer systems, a strong continuous absorption from the far infrared to visible light region has been observed in some of the systems studied. These systems may be useful for the development of light-emitting devices, which will emit in the various regions of the electromagnetic spectrum, including the visible light region. The emission in the deep ultraviolet light region may be used for sterilization, water purification etc.

Vacancy Induced Magnetism and Spin Filtering in 2D GaN Monolayer

Exotic properties functionalized by Ga or N atom vacancies in two-dimensional GaN monolayer have been predicted for the first time. A detailed ab-initio study of the structural, electronic, magnetic and optical properties of a 2D–GaN monolayer containing Ga or N atom vacancies has been performed. In the present study, we make two refinements in the density functional theory. At first, long range dispersion interactions not discussed so far have been accounted for. Further, norm-conserving pseudopotentials and plane waves are employed in generalized gradient approximation in contrast to earlier workers who have used soft or ultra-soft pseudopotentials. One observes that the strength of induced magnetism depends not on the separation of Ga-vacancies but on the number of Ga atom vacancies. The magnetism induced by N-atom vacancies is either zero or quite small. Spin filtering has been observed in many configurations. A strong continuous absorption from the far infrared region to the deep visible region is seen in some systems. It may be useful for development of photo-emitting devices which will emit in various regions of energy spectrum including visible emission. The emission of 2D-GaN monolayer lying in deep ultraviolet region may be used for sterilization, water purification etc.

Green Synthesis of Copper Nanoparticles Designed from Ocimum sanctum for Purification of Waste Water.

Green nanotechnology and its utility in synthesis of nanoparticles is an area of significant research intertest. For this project, synthesis of copper nanoparticles was done using Ocimum sanctum extract. Copper nanoparticles are gaining more attention in the field of agriculture, sensor, organic reactions, water purification etc. The prepared nanoparticles were characterized by XRD and UV–Vis spectroscopy. Method used for the synthesis of stable copper nanoparticles is rapid and ecofriendly. As we know, our river water is getting polluted mostly by waste coming out from our industries. Copper nanoparticles prepared by leaf extract are not hazardous to our environment. We have conducted our study by using Methylene blue dye (MB) and Rhodamine B (Rh B) dye. We have also studied the dye degradation reactions by using UV visible spectrophotometer.

Direct Osmotic Desalination Technique by Solar Energy

Over the last decade direct (forward) osmosis has attracted much attention in practical applications including artesian water desalination, green power generation, industrial water purification etc. In comparison with the traditional reverse osmosis process the separation is due to natural osmosis, providing lower energy cost for external pressure that is needed for reverse osmosis and lower membrane fouling potential. The main problem for the direct osmosis application efficiency is a selection of appropriate draw solute (otherwise known as a working substance). In the present paper diethyl ether (C₂H₅)₂O has been considered as a working substance having a relatively high osmotic pressure. Heating regeneration has been explored to obtain fresh water and recover the proposed draw solution. The advantage of the diethyl ether over known draw solutes has been discussed. It was noted that for further commercial applications of the diethyl ether as a working substance the membrane should have better characteristics of water permeability, stability, selectivity, and mechanical strength. The pilot device based on the described direct (forward) osmosis technique with the productivity of 1 m³/hr has been manufactured. In the beginning of 2020 the pilot device was successfully installed in a village of Navoiy Region, Uzbekistan to provide its inhabitants with the clean water.

Framework for clathrate hydrate flash calculations and implications on the crystal structure and final equilibrium of mixed hydrates

Clathrate hydrates, usually called gas hydrates, are compounds of great interest in oil industry, as well as in gas separation and storage, water purification etc … Like many other compounds that phase change, in this case from liquid water to non stoichiometric crystalline compound, modeling is required to understand and optimize the processes that involve them.Therefore, the classic thermodynamic equilibrium model is combined with mass balance calculations during gas hydrate crystallization. Two frameworks for performing clathrate hydrate thermodynamic flash calculations at constant volume are presented and compared to experimental results at low crystallization rate. The inputs are the quantity of mass (water and gas molecules), and the volume. The variable is temperature (three phases thermodynamic flash at a given temperature), while the volume is kept constant.The first framework suggests that the hydrate phase is growing at local thermodynamic equilibrium, without any reorganization of its content of the occupancy of the cavities. In the second framework, the hydrate phase can reorganize itself during growth (locally or completely). These frameworks are investigated, as well as the impact of the Kihara parameters uncertainties.These frameworks calculate well the final pressure, hydrate composition. In addition, the hydrate volume and mole amount in each phase is provided with reasonable accuracy. Note: uncertainties on the final pressure and hydrate volume are below 5%. Moreover, the results are quite sensitives to the value of the Kihara parameters, demonstrating the importance of their values for a given computer code.This work provides a more reallistic and comprehensive view of gas hydrate crystallization.

Carbonatation precipitate – origin, separation and uses

Managers and researchers are looking for new systems with minimum consumption of lime e.g. ultrafiltration. Nevertheless liming and carbonatation are still an important part of juice purification in the sugar industry. The complex process is influenced by many parameters such as lime addition, polysaccharides content and their composition, temperature, mixing intensity, recycling in juice purification etc. Carbonatation precipitate as well as the role of adsorbing nonsugars from the beet is connected with sedimentation and filtration characteristics and seems to be a promising raw material in many industries. Key parameters of the carbonatation lime as a by-product of sugar manufacture are size of crystals and aggregates together with polymorphism of the CaCO3 both for the filtration and for follow-up industrial applications. The common polymorph of carbonatation precipitate is calcite but also needle-like aragonite precipitates were found when deteriorated beet was processed. Carbonatation lime may be used as fertilizer, filler in adhesives or in plastics, and in many ecologic uses. It could be concluded that functional materials based on carbonatation lime is a challenging perspective, however, the extensive knowledge in carbonatation process is of primary importance.

Carbon Nanotubes: A Potential Concept for Drug Delivery Applications

The unique properties of carbon nanotubes (CNTs) make them a highly interesting and demandable nanocarrier in the field of nanoscience. CNTs facilitate efficient delivery of therapeutics like drugs, proteins, genes, nucleic acids, vitamins and lot more. Even though highly beneficial, the biocompatibility of CNTs is a major issue in their questioning their potential application in targeting drug delivery. Studies confirmed subdued toxicity of CNTs following slight modifications like functionalization, controlled dimensions, purification etc. A well-established mechanism for cellular internalization is an insistent need to attain a more efficient and targeted delivery. Recent patents have been thoroughly discussed in the text below.

Current experience and future perspectives of bromelain application in medicine

Bromelain is a complex mixture of different thiol endopeptidases which is derived from the pineapple stems (Ananas comosus, fam. Bromeliaceae). Bromelain is used in food industry for meat tenderizing, beer purification etc. A great number of studies conducted on cell cultures and experimental animals indicate that bromelain possesses antiedematous, analgesic, anti-coagulant, anti-inflammatory, immunomodulatory and hepatoprotective effect. However, there are only a few clinical studies which, under the clinical conditions, undoubtedly prove the therapeutic effects of bromelain in obesity treatment, sinusitis, tooth extraction pain, osteoarthritis, pityriasis rosea, burns and cardiovascular diseases such as angina pectoris, transient ischemic attack (TIA) or thrombophlebitis. The studies of chemoprotective activity have just been started, while the studies on humans have not been conducted yet. All studies confirm that bromelain is well tolerated as well as that it causes few side effects. Therefore, it is necessary to conduct new studies that would confirm the role of bromelain in the therapy of certain pathological changes. An overview of the clinical studies in which some bromelain pharmacological effects have been confirmed is presented in this paper as well as selected in vitro and in vivo studies which are the base for further clinical research.

Application of blood purification technique in autoimmune disease

The improvement of blood purification technologies in the recent years brings new methods of treating autoimmune diseases. Blood purification therapy mainly includes plasma exchange, immune adsorption and cell purification etc. It can rapidly remove a great amount of circulating pathological elements like autoantibodies,or remove the immune cells. It is effective for the treatment of refractory rheumatoid arthritis,severe systemic lupus erythematosus, acute autoimmune hemolytic, myasthenia gravis and other autoimmune diseases. But this is only a symptomatic treatment. Long-term steroid and immunosuppressive therapy are still needed to consolidate the curative effect. Key words: Blood purification; Autoimmune diseases

Application of Magnetizable Complex Systems in Biomedicine

Magnetic fluids or ferrofluids as they are often called mainly consist of nano sized iron oxide particles (Fe3O4 or γ-Fe2O3) that are suspended in carrier liquid. In recent years, substantial progress has been made in developing technologies in the field of magnetic microspheres, magnetic nanospheres and ferrofluids. Techniques based on using of these biocompatible magnetizable complex systems have found application in numerous biological fields viz. diagnostics, drug targeting, molecular biology, cell isolation and purification, radio immuno assay, hyperthermia causing agents for cancer therapy, nucleic acid purification etc. Biocompatible ferrofluids normally use water as a carrier medium. In order to prevent agglomeration the magnetic nanoparticles have to be stabilized by ionic interaction, a bilayer of an appropriate agent (e.g. fatty acid), aspartic and glutamic acid or peptides. Alternatively, the coprecipitation of ferrous/ferric ions is performed in the presence of appropriate biopolymer such as dextran, polyethylen glycol or polyvinyl alcohol. It has been shown that proteins and enzymes can be bound covalently to freshly prepared magnetite in the presence of carbodiimide. Several clinically important enzymes and proteins that include bovine serum albumin, streptokinase, chymotrypsin, dispase, glucose oxidase (GOD) etc., have been immobilized based on this method. The immobilized enzymes showed about 50-80 of the original added enzyme activity. This contribution will summarize the information about the ways to synthesize biocompatible magnetic nanoparticles and complexes containing them and the application of magnetic complex systems in biomedicine at magnetic drug targeting and hyperthermia.