Reverse Osmosis
Mostrando 37-44 de 44 artigos, teses e dissertações.
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37. Evaluation of Cleaning Strategies for Removal of Biofilms from Reverse-Osmosis Membranes
An evaluation was made of the efficiency of five classes of chemical cleaning agents for removing biofilm from spirally wound cellulose acetate reverse-osmosis membranes receiving influent with high or low levels of combined chlorine. Each cleaning regimen utilized one or more of the following types of chemical: (i) surfactants and detergents, (ii) chaotropi
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38. Comparison of microbiologic assay methods for hemodialysis fluids.
To help prevent pyrogenic reactions and bacteremia in hemodialysis patients, the Association for the Advancement of Medical Instrumentation and the Centers for Disease Control recommend microbiologic assay of hemodialysis fluids at least monthly. Five commercially available assay systems were evaluated by using the membrane filtration technique with standard
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39. Improved Fixation of Cellulose-Acetate Reverse-Osmosis Membrane for Scanning Electron Microscopy
Fixation of cellulose-acetate membranes with either glutaraldehyde-osmium tetroxide or glutaraldehyde-ruthenium tetroxide resulted in extensive electron beam damage. Beam damage was eliminated and the bacterial surface structure was preserved, however, when cellulose-acetate membranes were fixed with glutaraldehyderuthenium tetroxide and treated successively
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40. A rapid, direct method for enumerating respiring enterohemorrhagic Escherichia coli O157:H7 in water.
Simple, rapid methods for the detection and enumeration of specific bacteria in water and wastewater are needed. We have combined incubation using cyanoditolyl tetrazolium chloride (CTC) to detect respiratory activity with a modified fluorescent-antibody (FA) technique, for the enumeration of specific viable bacteria. Bacteria in suspensions were captured by
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41. Bacterial colonization and endotoxin content of a new renal dialysis water system composed of acrylonitrile butadiene styrene.
We measured endotoxin and bacterial levels in tap water, in water purified by reverse osmosis, and in dialysate samples over a 4-month period in a new 10-bed renal dialysis unit. Water treated by reverse osmosis is conducted to the 10 stations through 111 m of piping composed of acrylonitrile butadiene styrene (ABS). All determinations were made prior to the
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42. Quantitative microbiological monitoring of hemodialysis fluids: evaluation of methods and demonstration of lack of test relevance in single-pass hemodialysis machines with automatic dialysate proportioning with reverse osmosis-treated tap water.
Two methods for estimating the quantity of microorganisms present in hemodialysis fluid, a blood agar surface-spread plate method and a total-count water tester device impregnated with modified standard plate count agar (Millipore Corp., Bedford, Mass.), were evaluated. Both methods exhibited comparable precision; however, colony counts obtained with the tot
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43. Changes in bone histoquantitative parameters and histochemical staining reactions for aluminium in a group of patients with chronic renal failure following a reduction in the aluminium concentration of the haemodialysis fluid.
Bone biopsies from a group of 16 patients in chronic renal failure treated by intermittent haemodialysis were available for histoquantitative and histochemical assessment before and after the introduction of reverse osmosis treatment of the dialysis fluid. This treatment reduced the aluminium concentration of the fluid from 1.15 mg/l to less than 0.06 mg/l.
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44. Characterization of a partially purified methanol-soluble heat-stable Escherichia coli enterotoxin in infant mice.
While studying the involvement of cyclic adenosine 3',5'-monophosphate (cAMP) in the fluid secretion caused by heat-stable enterotoxin (ST) from Escherichia coli P16 in infant mice, it was noted that the culture filtrate containing ST also contained large amounts of cAMP. The present paper details attempts to obtain a cAMP-free ST preparation. The organisms