As the water flows down and passes over a packing material possessing a large air-liquid inter phase, the volatile organic compounds (VOC) are transferred from the water to the air. It is effective in removing organic as well as inorganic contaminants including hydrogen sulfide. Distillation In this technology, water is heated until it turns to steam, which is then condensed as distilled pure water, free of most dissolved or any solid contaminants including bacteria and viruses. Because distilled water is free of all minerals, it may not be ideal for drinking. Ion Exchange This is a process is used commonly for water softening, by which ions that are dissolved in water are transferred to, and held by, a solid material or exchange resin.
1.4.2 Creams :- Creams are homogenous, semisolid preparations having an opaque emulsion system. Their consistency depends on type of emulsion either (o/w) or an (w/o).They are intended for application to skin or to other membranes. 22.214.171.124Hydrophobic creams (w/o) :- Hydrophobic creams are usually anhydrous and absorb only small amounts of water. They contain w/o emulsifying agents like wool fat, sorbitan esters, and monoglycerides. 126.96.36.199 Hydrophilic creams (o/w) :- Hydrophilic creams contain bases that are miscible with water.
It is a selective differential medium for Listeria spp. and used in the preliminary enrichment step for the isolation of L. monocytogenes from foods. In this medium, there are peptone, yeast extract, and starch provide nitrogen, vitamins, minerals, and cofactors required for growth of Listeria spp. while sodium chloride maintains the osmotic equilibrium of the medium. PALCAM media agar is highly selective due to the presence of lithium chloride, ceftazidime, polymyxin B and acriflavine hydrochloride, which suppress growth of most non-Listeria spp.
Hence, a calcium chloride and cotton were filled inside a drying tube. The condenser was wrapped with parafilm and a paper towel to avoid moistures from entering. The reagent will act as nucleophilic addition to acetone and work up with hydrochloride acid to synthesize 2-methylhexanol. Throughout this process, the solution turns dark grey and develop white precipitates. This step indicate that Grignard reagent was generated, and the extra white precipitates were magnesium.
Benedict's reagent is an alkaline solution containing Cu(II) ions, which oxidize the aldehyde to a carboxylic acid. In turn, the cupric ions are reduced to cuprous oxide, which forms a red precipitate. Chemical reaction: RCHO + 2Cu2+ + 4OH- → RCOOH + Cu2O + 2H2O Again, Benedict’s solution contains copper sulphate. Reducing sugars, glucose and fructose, reduce soluble blue copper sulphate, containing copper(II) ions to insoluble red-brown copper oxide containing copper(I). This accounts for the precipitate formed.
The remained raw unwashed biodiesel is methanol. Methanol is a solvent which captures soap and other impurities and holds them dissolved in the biodiesel. Water soaks up that methanol, releasing impurities to be washed away with water. Visual inspection indicates successful biodiesel reaction in 2 distinct layers which is the lighter color biodiesel and darker color glycerol. Glycerol, the remaining part of the triglyceride, is a byproduct of the reaction, which is later removed before use.
RO is the point at which a weight is connected to the concentrated side of the layer compelling cleaned water into the weaken side, the rejected debasements from the concentrated side being washed away in the reject water. RO can likewise go about as a ultra filter expelling particles, for example, a few microorganisms that might be too huge to go through the pores of the membrane. FIGURE 2 Electrodialysis Electrodialysis is viable in expelling fluoride and nitrate from water. This procedure additionally utilizes layers in any case; coordinate electrical streams are utilized to pull in particles to the other side of the treatment chamber. This framework incorporates a wellspring of pressurized water, coordinate momentum control supply and a couple of particular films.
This process consists of suspending the drug particles in a low-melting polymer or wax and pumping the consequential slurry through an atomizer into a spray dryer in which cold air is circulated. The slurry droplets thicken on coming in contact with the air and are collected in the same manner as the spray-dried product. The spray congealing process requires a much higher ratio of coating agent to active material than does spray drying because only the molten coating agent constitutes the liquid phase. Encapsulation of drug-containing cores and granules (resins) in the manufacture of reservoir-type oral controlled released product can be accomplished by the following coating methods: 123-125 c) Pan Coating For encapsulation, Pan coaters are
First, bismuth subnitrate was added into the graduated cylinder. Bismuth subnitrate is a white powder which soluble in water. The purpose of adding bismuth subnitrate is to mix the solute (bismuth subnitrate) and solvent together. Methylcellulose is a hydrophilic white powder in pure form and dissolves in only cold water, forming a clear viscous solution or gel. In the first boiling tube, the solution consists of 2 g of bismuth nitrate and water.
Nano sized metal oxides are prepared via hydrolysis of precursors, usually alcoxides in alcoholic solution which results in the formation of corresponding oxo-hydroxide. After that condensation of molecules is done by giving off water which leads to the formation of a network of the metal hydroxide wghich means the hydroxyl-species undergo polymerization by condensation reaction and dense porous gel is formed. It is further dried and this calcinations leads to the formation of ultrafine nano oxides of metals (Kobayashi et al., 2001). 2.3.3 Microemulsion technique. Microemusion or direct/inverse micelles is an excellent approach based on the formation of micro/nano-reaction vessels using a ternary mixture of water, a surfactant and oil.