Comparison of the Microbicidal Activities of Superoxidized and Ozonated Water in the Disinfection of Endoscopes

2003 ◽  
Vol 31 (4) ◽  
pp. 299-306 ◽  
Author(s):  
M Urata ◽  
H Isomoto ◽  
K Murase ◽  
A Wada ◽  
K Yanagihara ◽  
...  
Keyword(s):  
Detection Limit ◽  
Microbial Contamination ◽  
Strong Acid ◽  
Weak Acid ◽  
Acid Water ◽  
Endoscopy Unit ◽  
Micro Organisms ◽  
Upper Gastrointestinal ◽  
Mechanical Cleaning ◽  
Ozonated Water

The microbicidal activities of super-oxidized water (electrolysed strong acid water [ESAW] or electrolysed weak acid water [EWAW]), ozonated water, 0.05% chlorhexidine and 2% glutaraldehyde were tested against seven strains of clinical micro-organism isolates. Following incubation of bacterial suspensions in ESAW and EWAW for 10 s, the number of micro-organisms was reduced below the detection limit. The microbicidal activities of ESAW and EWAW were similar to that of glutaraldehyde, and superior to ozonated water and 0.05% chlorhexidine. The microbicidal activities of ESAW, EWAW and ozonated water were markedly diminished in the presence of albumin. Microbial contamination of upper gastrointestinal endoscopes was detected after 90 endoscopic procedures, but treatment of the endoscope with ESAW, EWAW or ozonated water eradicated the microbes. These results indicate that ESAW and EWAW are effective disinfectants after mechanical cleaning of upper gastrointestinal endoscopes, and can, therefore, be used in the endoscopy unit.

Effect of electrolyzed strong acid water on peritoneal irrigation of experimental perforated peritonitis

Surgery Today ◽  
2009 ◽  
Vol 39 (6) ◽  
pp. 514-517 ◽  
Author(s):  
Akio Kubota ◽  
Keisuke Nose ◽  
Takeo Yonekura ◽  
Takuya Kosumi ◽  
Katsuji Yamauchi ◽  
...  
Keyword(s):  
Strong Acid ◽  
Acid Water ◽  
Perforated Peritonitis

scholarly journals Experiments on the Generation of Strong Acid Water from Sedimentary Mudstone.

1997 ◽  
Vol 20 (6) ◽  
pp. 419-423
Author(s):  
Hisashi SHIMOGAKI ◽  
Takahiro OHYAMA ◽  
Kameichiro NAKAGAWA
Keyword(s):  
Strong Acid ◽  
Acid Water

Comparative analysis of strong and weak acid pretreatment methods under pressurized and non-pressurized conditions for agro-industrial waste of apple pulp

2018 ◽  
Vol 29 (6) ◽  
pp. 1038-1052
Author(s):  
Ece Ümmü Deveci ◽  
Çağdaş Gönen
Keyword(s):  
Statistical Design ◽  
Strong Acid ◽  
Weak Acid ◽  
Raw Material ◽  
Sugar Concentration ◽  
Optimum Level ◽  
Acid Pretreatment ◽  
Industrial Plants ◽  
Sulfuric Acid Pretreatment ◽  
The Face

It is well known that energy-related emissions have been increasing the global warming and pushing the climate change. In the face of this situation biomass-based biofuels, which is a kind of renewable energy source, are great alternatives instead of fossil derivative fuels. Moreover, biomass can be found easily and widely, which makes it an economical alternative. Biological conversation rate of the biomass to the biofuel is insufficient because of the molecular structure of the biomass. Pretreatment is required to increase the bioavailability of the biomass as the raw material. In this study, weak and strong acid pretreatments are studied under pressurized and non-pressurized conditions for apple pulp as biomass, which is an agro-industrial residue coming from industrial plants. Box-Behnken statistical design is used to determine the optimum level of some factors as time, chemical dose, and raw material dose. While the maximum total sugar concentration was found to be 23.71 g/L with sulfuric acid pretreatment, the reduced sugar concentration under pressurized conditions with strong acid pretreatment was found as 17.00 g/L.

Effect of autotransformation on the layer charge of smectites determined by the alkylammonium method

Clay Minerals ◽  
1997 ◽  
Vol 32 (4) ◽  
pp. 623-632 ◽  
Author(s):  
M. Janek ◽  
P. Komadel ◽  
G. Lagaly
Keyword(s):  
Aqueous Dispersion ◽  
Strong Acid ◽  
Acid Sites ◽  
Weak Acid ◽  
Layer Charge ◽  
Exchange Method ◽  
Density Distributions ◽  
Titration Curves ◽  
The Mean ◽  
Strong Acid Sites

AbstractHydrogen-forms of <2 µm fractions of six bentonites of various Fe contents were prepared by H+→OH-→H+ ion exchange using resins. Potentiometric titration curves revealed that the number of strong acid sites varied and accounted for 60-95% of the total acidity in the freshly prepared H-forms. The number of strong acid sites decreased and that of the weak acid sites increased on ageing. The process of autotransformation in aqueous dispersion at 90~ was completed within four days. Layer-charge distributions of all samples were inhomogeneous with layer charges from 0.25-0.39 Eq/unit O10(OH)2. Oxalate pretreatment of the samples resulted in changes in the layer-charge distribution due to the removal of readily soluble phases which may have blocked exchange sites. After autotransformation, the alkylammonium exchange method revealed inhomogeneous charge density distributions; the fraction of layers of the highest charge decreased. Comparison of total CEC obtained from potentiometric curves and interlamellar CEC calculated from the mean layer charge confirmed attack of protons from particle edges. However, for several samples the structural attack may also occur from the interlayer space. Autotransformation of the Hsmectites decreased the mean layer charge. Protons probably attack the Mg(O,OH)6 octahedra preferentially during the autotransformation.

Ion Exchange Functional Nanofibers

2009 ◽  
Vol 1240 ◽  
Author(s):  
Prabir K Patra ◽  
Sukalyan Sengupta
Keyword(s):  
Ion Exchange ◽  
Cation Exchange ◽  
Average Diameter ◽  
Strong Acid ◽  
Weak Acid ◽  
Exchange Capacity ◽  
Orifice Diameter ◽  
Pump Speed ◽  
Acid Cation ◽  
Weak Base Anion Exchange

AbstractWe have synthesized a series of ion exchange functionalized fibers (IXF) from polystyrene (PS) and polyacrylonitrile (PAN). To obtain strong-acid cation exchange fibers, polystyrene was sulfonated using specific sulfonation protocols. Micron sized fibers (average diameter of 100m) were then produced from the functionalized polystyrene using a single-screw extruder equipped with a 30 hole spinneret with orifice diameter of 0.5 mm with a precise screw speed of 5 rpm, pump speed of 15 rpm, and with a feed rate of 2.4 cc/min. The extruder zone temperature was kept at 250 – 270 °C. Fiber was drawn at 120 degree with a draw ratio of 2. Electrospinning of functionalized polystyrene was also carried out to produce ultrafine functionalized fibers of 100 nm in average diameter. We have also electrospun polystyrene and polyisoprene blended nanofibers to increase the strength of the resulting blend nanofibers compared to pure PS nanofibers. To synthesize weak-acid cation exchange fibers polyacrylonitrile (PAN) was electrospun and the nanofibers obtained were alkaline hydrolyzed with 2 N NaOH for 20 minutes at room temperature to convert nitrile bonds to carboxylate. Cation exchange capacity (CEC) of the microfibers and nanofibers was determined. Sulfonated PS microfibers show high CEC of 4.0 meq/gm compared to that of nanofibers with 2.5 meq/gm. CEC of blended nanofibers of PS and polyisoprene was 2.0 meq/gm. In case of PAN fibers, nanosized electrospun fibers were found to show a CEC of 1.5 meq/gm. Weak-base anion exchange fiber synthesis was undertaken using appropriate protocol and its CEC was measured. For all IXF synthesized, fiber diameter was measured using SEM, degree of functionalization was qualitatively determined using FTIR and ion exchange capacity was computed after mass balance on a binary exchange system after equilibrium.

scholarly journals A method for measuring the cleaning effect of flushing disinfectors

1980 ◽  
Vol 84 (3) ◽  
pp. 321-330 ◽  
Author(s):  
Åke Cederberg ◽  
Kai Österberg
Keyword(s):  
Water Temperature ◽  
Bacillus Stearothermophilus ◽  
Mechanical Effect ◽  
Hot Water ◽  
Flushing Time ◽  
Before And After ◽  
Micro Organisms ◽  
Mechanical Cleaning

SUMMARYA method is presented with which the mechanical cleaning effect of flushing disinfectors can be estimated independently of the thermal disinfecting effect of the hot flushing water. This makes it possible to specify the demands to be placed on the disinfecting effect of flushing with water of 85°C or more.Bacillus stearothermophilus spores suspended in faeces were used as indicators because of their non-sensitivity to the hot-water temperature. Their elimination by flushing could thus be attributed to the mechanical effect of the water and not to the disinfecting effect of the temperature. A simple bacteriological technique was used, and the elimination factor (EF) was calculated as the ratio of the number of micro-organisms in the contamination before and after flushing. By using flushing water below 50°C for 130 s the EF on a bedpan was about 104–106. The effect of flushing with water of the same temperature for only half that time was somewhat weaker and when the temperature was raised to 85 °C after half the flushing time the effect was somewhat stronger.It can be presumed that the conventional disinfecting phase with hot (85 °C) water for about 45 s in the commonly used flushing units could be substantially shortened and the costs of their use thereby reduced.

Zinc speciation in soil solutions of Vertisols

Soil Research ◽  
1996 ◽  
Vol 34 (3) ◽  
pp. 369 ◽  
Author(s):  
YP Dang ◽  
KG Tiller ◽  
RC Dalal ◽  
DG Edwards
Keyword(s):  
Soil Solution ◽  
Strong Acid ◽  
Weak Acid ◽  
Solution Ph ◽  
Chelex 100 ◽  
Inorganic Species ◽  
Soil Solutions ◽  
Cation Exchange Resins ◽  
Highly Correlated ◽  
Exchange Resins

Soil solutions were obtained by a centrifugation method from 14 unfertilised and fertilised Vertisols. The soil solutions were analysed for all major cations and anions and organic carbon (C). Chemical speciation of zinc (Zn) in the soil solutions calculated with the aid of the computer program GEOCHEM showed that Zn in tile soil solution exists mainly as free Zn2+ ions in these soils. Complexation of total soluble Zn by organic and inorganic ligands constituted 40% and 50%, respectively, of total soluble Zn in fertilised and unfertilised soil solutions. The organo-Zn complexes constituted <10% of the total soluble Zn. The inorganic Zn complexes, ZnHCO3+ and ZnCO3, constituted 60–75% of the total inorganic Zn complexes. The Zn complexes with SO24- and OH- were less than or equal to 5% each of the total inorganic species in unfertilised soils; ZnSOo4 complexes were more common in fertilised soils. The activities of Zn were extremely low (0.01–0.1 µM) in unfertilised soils and were inversely related to soil solution pH. The experimentally determined solubility lines for Zn2+ in the soil solution were undersaturated with respect to the solubility of any known mineral form of Zn. Zn2+ activity was mainly determined by adsorption-desorption reactions. The weak acid ion exchangers, Chelex-100 and Bio Rex-70, retained smaller amounts of Zn front the soil solutions than the strong acid exchangers, AG 50W X2, AG 50W X4, and AG 50w X8. Soil solution pH strongly affected Zn concentrations in soil solutions. The amount of total soluble Zn present as Zn2+ ions as calculated by GEOCHEM was highly correlated with tile amount of soluble Zn retained by the cation exchange resins. In the case of Chelex-100, these amounts were equal, confirming the usefulness of Chelex-100 to estimate Zn2+ ions.

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