THE VIABILITY OF THE BACTERIUM PSEUDOMONAS FLUORESCENS IN AQUEOUS SOLUTIONS OF FORMALDEHYDE

1932 ◽  
Vol 7 (1) ◽  
pp. 139-146
Author(s):  
ROBERT H. BEDFORD
Keyword(s):  
Aqueous Solutions ◽  
Pseudomonas Fluorescens ◽  
Tap Water ◽  
Lethal Effect ◽  
Distilled Water ◽  
Water Suspension ◽  
Total Solids ◽  
Bilge Water

It was found that a 1% solution by volume killed 2000 million bacteria in a distilled water suspension at 25° in 10 minutes, but when the suspension was made with tap water containing 3 mg. of total solids the time was increased to 15 minutes, and only 425 millions were killed in 20 minutes when the suspension was made with bilge water containing 0.86% organic matter.When the temperature was lowered the lethal effect was reduced so that a 2.5% solution which killed 2000 millions in 15 minutes at 25° only killed 125 millions at 4°.Ice was sterilized under commercial conditions with 5 parts of formaldehyde to 100,000 parts of water.

scholarly journals Sensory profiles of sweeteners in aqueous solutions

2011 ◽  
Vol 24 (No. 6) ◽  
pp. 283-287 ◽  
Author(s):  
A. Šedivá ◽  
Z. Panovská ◽  
J. Pokorný
Keyword(s):  
Aqueous Solutions ◽  
Bitter Taste ◽  
Sucrose Solution ◽  
Tap Water ◽  
Relative Accuracy ◽  
Distilled Water ◽  
Iso Standards ◽  
Metallic Taste ◽  
Different Types ◽  
Sensory Profiles

Sensory profiles of saccharin, acesulfame K, aspartame, and neotame were compared with that of sucrose in three different types of water (tap water, commerical Crystalis water, and distilled water) under the conditions of the respective ISO standards. The intensities of off-flavours, especially bitter and metallic tastes, were higher in the solutions of synthetic sweeteners than in that of sucrose. The aspartame solution was the sample closest to the sucrose solution, and the intensity of off-flavours was significantly higher in acesulfame solution. Ratings of the bitter taste were related to those of the metallic taste, the relation being semilogarithmic. The performancies of different assessors were nearly the same in all ratings, and the absolute values of the ratings of sweetness and different off-flavours had the same repeatabilities. The relative accuracy was, naturally, much higher in off-flavours than in the case of sweetness.  

Penetration Dynamics of Solid Particles into Liquids High-Speed Experimental Results and Modelling

2005 ◽  
Vol 473-474 ◽  
pp. 429-434 ◽  
Author(s):  
Olga Verezub ◽  
György Kaptay ◽  
Tomiharu Matsushita ◽  
Kusuhiro Mukai
Keyword(s):  
Contact Angle ◽  
Particle Size ◽  
Aqueous Solutions ◽  
Particle Velocity ◽  
Weber Number ◽  
High Speed ◽  
Solid Particles ◽  
Bulk Liquid ◽  
Distilled Water ◽  
Critical Weber Number

Penetration of model solid particles (polymer, teflon, nylon, alumina) into transparent model liquids (distilled water and aqueous solutions of KI) were recorded by a high speed (500 frames per second) camera, while the particles were dropped from different heights vertically on the still surface of the liquids. In all cases a cavity has been found to form behind the solid particle, penetrating into the liquid. For each particle/liquid combination the critical dropping height has been measured, above which the particle was able to penetrate into the bulk liquid. Based on this, the critical impact particle velocity, and also the critical Weber number of penetration have been established. The critical Weber number of penetration was modelled as a function of the contact angle, particle size and the ratio of the density of solid particles to the density of the liquid.

Shear degradation resistance of star poly(ethyleneimine) - polyacrylamides during elongational flow

e-Polymers ◽  
2011 ◽  
Vol 11 (1) ◽  
Author(s):  
Ming Duan ◽  
Shenwen Fang ◽  
Liehui Zhang ◽  
Fuxiao Wang ◽  
Peng Zhang ◽  
...  
Keyword(s):  
Shear Rate ◽  
Aqueous Solutions ◽  
Relative Viscosity ◽  
Reduction Rate ◽  
Elongational Flow ◽  
Exponential Dependence ◽  
Distilled Water ◽  
Shear Stability ◽  
Low Viscosity ◽  
Shear Degradation

AbstractAn experimental study of the flow-induced scission behaviour of four star hydrolyzed polyacrylamides (HPMA) with different arms during planar elongational flow in a cross-slot flow cell is described. The results showed that the shear stability of linear HPAM in distilled water was not essentially different from star HPAM. Polymer scission was not observed in either system in a shear rate range from 20,000 to 100,000s-1, which can be attributed to the strong polyelectrolyte behaviour of HPAM in distilled water. However, at the same shear rate, the star HPAMs exhibited superior shear stability in comparison to the linear HPAMs in aqueous solutions containing NaCl (CNaCl=0.2-1.0%wt) and, in particular, the initial reduction rate of relative viscosity (R) decreased with the degree of branching of the HPAMs. In addition, it was found that the R of five HPAMs in NaCl aqueous solutions exhibited an exponential dependence on shear rate, in which the coefficient C1 can be used to quantitatively evaluate shear stability. In star HPAM NaCl aqueous solutions, the increase of R with shear rate is very likely due to the decrease of the hydrodynamic radius (Rh) of these HPAMs, while the increase of R with NaCl concentrations can be attributed to the relatively low viscosity of these polymers at high NaCl concentrations.

Influence of Learning on Taste Preferences

1966 ◽  
Vol 19 (2) ◽  
pp. 445-446 ◽  
Author(s):  
Paul Thomas Young
Keyword(s):  
Tap Water ◽  
Taste Preferences ◽  
Distilled Water

Further discussion of the Schnorr and Brookshire study of the preference between distilled water and tap water, with comments and suggestions.

scholarly journals Hydraulic Conductivity of Compacted Lime-Softening Sludge Used as Landfill Liners

2019 ◽  
Vol 230 (12) ◽  
Author(s):  
Agnieszka Dąbska
Keyword(s):  
Hydraulic Conductivity ◽  
Moisture Content ◽  
Tap Water ◽  
Distilled Water ◽  
Landfill Liners ◽  
Water Permeation ◽  
Lime Softening ◽  
Approximate Polynomial ◽  
Hazardous Waste Landfills

AbstractThe research goal was to investigate the hydraulic conductivity of compacted lime-softening sludge as a material to be applied to landfill liners. In doing so, the effect of compaction and moulding moisture content on the sludge hydraulic conductivity was assessed. An approximate polynomial k10mean at hydraulic gradients ≥30 for degree of compaction (0.95–1.05) and moulding moisture content (28%–36%) was determined. The results of short-term tap water permeation tests revealed that all hydraulic conductivity values were less than 2.5•10–8 m/s. A lowest hydraulic conductivity of 6.5•10–9 m/s, as well as a corresponding moisture content of 31% were then established. The long-term hydraulic conductivity was measured with tap water, distilled water, NaOH and HCl solutions and municipal waste leachate. The factors of permeating liquids and permeation time significantly affected the initial hydraulic conductivity. The long-term hydraulic conductivity increased for NaOH and HCl solutions and decreased for tap and distilled water. A significant reduction of hydraulic conductivity was observed for leachate permeation. The investigated material met the requirements for the liner systems of inert landfill sites regardless of pH and the limit value for hazardous and non-hazardous waste landfills.

Evaluation of Millipore Cartridge-type Water Treatment Systems for Microbiological Applications

1979 ◽  
Vol 42 (8) ◽  
pp. 654-655 ◽  
Author(s):  
BARBARA L. GREEN ◽  
WARREN LITSKY
Keyword(s):  
Water Treatment ◽  
Produced Water ◽  
Tap Water ◽  
Ionic Species ◽  
Distilled Water ◽  
Microbiology Laboratory ◽  
Type Water ◽  
Control Water ◽  
Q System

Two different cartridge-type water treatment systems were evaluated for use in the microbiology laboratory, employing the Distilled Water Suitability Test (DWST). The Milli-Q system fed by distilled water and the Milli-R/Q system fed by tap water both produced water acceptable for microbiological use as measured by the DWST. Concentrations of ionic species (as measured by conductivity) in Milli-Q and Milli-R/Q products were significantly lower than in the double distilled control water.

Changes in specific airway resistance during prolonged breathing of moist air

1970 ◽  
Vol 48 (9) ◽  
pp. 592-597 ◽  
Author(s):  
G. Norris Melville ◽  
W. T. Josenhans ◽  
W. T. Ulmer
Keyword(s):  
Relative Humidity ◽  
Water Content ◽  
Water Loss ◽  
Healthy Subjects ◽  
Airway Resistance ◽  
Tap Water ◽  
Distilled Water ◽  
Moist Air ◽  
Specific Airway Resistance ◽  
Water Elimination

Effects of increased water content of inspired air at 21–38 °C on specific airway resistance (sRaw) in 107 healthy subjects were measured with a body plethysmograph. Mean sRaw increased insignificantly at 23 °C with 92% relative humidity (water content, 20.7 g∙m−3) for up to 71 h but became significant at 6 h with water content 25 g∙m−3. Increases were greater when evaporated tap water was inhaled than when distilled water was used. It is postulated that the increase in sRaw is due to mucosal swelling and to contaminants in tap water. A theory of respiratory "water elimination" is proposed to replace the concept of respiratory water loss.

INFLUENCE OF ORGANIC MATTER ON THE GERMICIDAL EFFICIENCY OF QUATERNARY AMMONIUM AND HYPOCHLORITE COMPOUNDS

1948 ◽  
Vol 26f (2) ◽  
pp. 91-104 ◽  
Author(s):  
C. K. Johns
Keyword(s):  
Staphylococcus Aureus ◽  
Organic Matter ◽  
Quaternary Ammonium ◽  
Tap Water ◽  
Skim Milk ◽  
Distilled Water ◽  
Water Solutions ◽  
E Coli ◽  
Test Organisms ◽  
High Concentrations

Using Staphylococcus aureus and Eschericha coli as test organisms, the influence of various concentrations of skim milk on the germicidal potency of Roccal and of Dalglish hypochlorite solutions was studied. Both germicides retained their activity in the presence of unexpectedly high concentrations of skim milk, especially against S. aureus. Small concentrations frequently showed a slight potentiating effect in both laboratory and plant tests. The effectiveness of the hypochlorite fell off sharply beyond a certain concentration, while that of Roccal declined more gradually. Solutions of Roccal prepared with tap water were decidedly less active against E. coli than those prepared with distilled water. With the hypochlorite, tap water solutions were equally effective. Against S. aureus, a similar difference was noted although to a lesser extent. Added skim milk depressed the germicidal action of tap water solutions of Roccal to a greater extent than for distilled water solutions, while for the hypochlorite the reverse held true.

THE SEPARATION OF CALF THYMUS NUCLEIC ACID AND HISTONE BY ALCOHOL–SALT PRECIPITATION

1955 ◽  
Vol 33 (1) ◽  
pp. 263-271 ◽  
Author(s):  
L. B. Smillie ◽  
A. M. Marko ◽  
G. C. Butler
Keyword(s):  
Sodium Chloride ◽  
Nucleic Acid ◽  
Aqueous Solutions ◽  
Distilled Water ◽  
Salt Precipitation ◽  
Salt Solutions ◽  
Desoxyribonucleic Acid ◽  
Concentrated Aqueous Solutions ◽  
Calf Thymus ◽  
Quantitative Separation

Extraction of the histone of thymonucleoprotein with alcohol and salt has been studied with varying concentrations of alcohol, sodium chloride, and nucleoprotein and with varying pH and temperature. The addition of 0.5–1.0 volumes of ethanol to a solution of nucleoprotein (approximately 1 mgm. N/ml.) in 3 M sodium chloride has been found to effect an almost quantitative separation of desoxyribonucleic acid and protein. It has proved feasible to prepare concentrated aqueous solutions of the extracted protein by successive dialysis against strong salt solutions at −10 °C. and against distilled water at 5 °C. followed by pervaporation at 5 °C. The properties of the isolated nucleate have indicated a highly polymerized product.

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