lactide was synthesized by reverse polymerization of low molecular weight poly(lactic acid) with two different molecular weights:1500 and 2500. two different lactide purification processes such as: recrystallization in ethyl acetate and washing the crude lactide with ether before recrystallization in ethyl acetate were evaluated. it has been demonstrated that increasing the molecular weight of ...

growing applications of phenylalanine dehydrogenase (phedh) enzyme in the medical and pharmaceutical industries encourages researchers to seek simple, fast and economical alternative purification methods. with goal of finding a new technique, the extraction and purification of recombinant bacillus badius phedh in polyethylene glycol 6000 (peg-6000) and ammonium sulfate aqueous two-phase systems...

We present a novel method to purify quantum states, i.e. purification through Zeno-like measurements, and show an application to entanglement purification. PACS numbers: 03.65.Xp, 03.67.Mn

streptococcus iniae is a major cause of serious bacterial infections in both fish and human beings. capsular polysaccharide (cps) of s. iniae is vital to evade phagocytic clearance of the host and serves as an important protective antigen of s. iniae infection in aquatic animals. the cpsdgene was determined to be highly conservative in capsule polysaccharide operon. prokaryotic expression of th...

antivenoms have been used successfully for more than a century and up to now constitute the only effective treatment for snakebites .the production of antivenin started long time ago when the calmette was prepared the antivenom in 1894.the method currently used to prepare antivenom by most of the manufacturers are originated from the method of pope which was develop in 1938. several new appr...

cloning and expression of the l-phenylalanine dehydrogenase gene, from b. sphaericus in e. coli were done. the gene was cloned in the vector pet16b and transformed into e. coli bl21 (de3). the functional form of the l-phenylalanine dehydrogenase enzyme was purified by affinity purification techniques, taking advantage of the ability of this enzyme to bind to the nucleotide site affinity dye, re...

superoxide dismutase (sod) is an important antioxidant that protects many types of cells from the free radical damage. one of the possible ways for the use of sod is its incorporation in liposomes. the aim of this study was to investigate the effect of cationic phospholipids on the entrapment of human erythrocyte superoxide dismutase (cu/zn sod) in liposomes. also, in the present study, we exam...

Marine diesel engine lubricating oil after long-term use, due to pollution and chemical activity, internal impurities increased, lubrication effect gradually deteriorated. The purification device based on balanced charge agglomeration (BCA) can realize the on-line of oil. In order further improve efficiency, a control system PLC is designed in this paper. consists complex electromechanical inte...

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this research has focused on isolation and characterization of a strain of bacillus sp. from alkaline soil, which was able to produce extracellular alkaline protease at phs ranging from 8 to 11 and temperatures of 20 to 50ºc. also the impact of different carbon andnitrogen sources were investigated. the yield and fold of enzyme purification was 24% and 50 times, respectively. molecular weight o...