scholarly journals Sensitivity of Assessors to Ferrous Salts

2009 ◽  
Vol 27 (Special Issue 1) ◽  
pp. S333-S336 ◽  
Author(s):  
Z. Panovská ◽  
A. Váchová ◽  
J. Řeřichová
Keyword(s):  
Tap Water ◽  
Ferrous Sulphate ◽  
Distilled Water ◽  
Basic Taste ◽  
Best Estimate ◽  
Metallic Taste ◽  
Threshold Range

Taste is the chemical sensation whose function is not very well known. Recently it was shown that the range of taste is more extensive than the five basic taste sweet, salty, bitter, sour and umami. A metallic taste has been suggested as another basic taste, but its mode of perception is not well understood and has not been really accepted in the taste literature. Ferrous sulphate solutions were presented to the assessors so their sensitivity and best estimate thresholds (BET) were measured. The best estimated threshold range was 0.00049–0.00669 g/l for demineralised water, 0.00079–0.00669 g/l for distilled water and 0.00108–0.00669 g/l for tap 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.  

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.

Effects of Water Quality and Spray Volume on Glyphosate Phytotoxicity

Weed Science ◽  
1979 ◽  
Vol 27 (1) ◽  
pp. 38-41 ◽  
Author(s):  
P. W. Stahlman ◽  
W. M. Phillips
Keyword(s):  
Water Quality ◽  
Tap Water ◽  
Herbicidal Activity ◽  
Inorganic Salts ◽  
Distilled Water ◽  
Volume Activity ◽  
Spray Solution ◽  
Spray Volume ◽  
Test Plants ◽  
Effective Carrier

Several inorganic salts added to the spray solution reduced the herbicidal activity of glyphosate [N-(phosphonomethyl)glycine]. Of the salts tested, iron and aluminum reduced herbicidal activity most. Reductions by calcium and zinc were moderately severe; by magnesium, moderate; by potassium and sodium, none. The reduction in phytotoxicity seems to be caused by cations, but factors other than valence also may be involved.Reduction in phytotoxicity was related to salt concentration and spray volume. Glyphosate at 0.84 kg/ha in 93 to 374 L/ha distilled water killed test plants. Tap water was an equally effective carrier at 93 and 187 L/ha volumes, but was significantly less effective at the 374 L/ha volume. Activity decreased as the molar concentration of CaCl2 increased to 0.01. Herbicidal activity was eliminated at 0.01 M and 374 L/ha; however, concentrations of CaCl2 exceeding 0.04 M reversed the trend and reacted similarly to a 0.005 M solution, which approximates the minimum hardness of most ground waters in Kansas.

scholarly journals Experiments on Freeze-Bonding Between Ice Blocks in Floating Ice rubble

1986 ◽  
Vol 32 (112) ◽  
pp. 397-403 ◽  
Author(s):  
R. Ettema ◽  
J.A. Schaefer
Keyword(s):  
Tap Water ◽  
Contact Period ◽  
Distilled Water ◽  
River Waters ◽  
Air Temperatures ◽  
Strength Behavior ◽  
Series Of Experiments ◽  
Bond Strengths ◽  
Saline Solutions ◽  
Thick Layers

AbstractSeries of experiments were conducted with the aim of determining the influences of the following factors on freeze-bonding between contacting ice blocks in floating ice rubble: pressure normal to the contact plane, period and area of contact, and salinity of the water in which freeze-bonding occurred. Freeze-bonding between ice blocks in air was also investigated. The experiments were conducted with water and air temperatures of about 0°C and normal pressures, between ice blocks, up to 4 kPa. This range of normal pressures may occur hydrostatically between ice blocks in layers of floating ice rubble up to about 10 m thick, or in 2-3 m thick layers which are in a passive Rankine state of pressure. The experiments show that stronger freeze-bonds develop between ice blocks in distilled water, tap water, and water from the Iowa River than develop between ice blocks contacting in air at 0°C. However, stronger freeze-bonds developed in air at 0°C than developed between ice blocks in 0°C saline (NaCl) solutions with salinities in excess of 12.5% by weight. The strength of freeze-bonding increased linearly with contact period for ice blocks in distilled, tap, and river waters, but did not increase with contact period for ice blocks contacting in saline solutions or in air. The results of the experiments are useful contributions to explanations of the shear-strength behavior of a layer of floating ice rubble. For example, thicker layers of ice rubble may show greater cohesive behavior, because normal pressures and thus freeze-bond strengths increase with layer thickness.

scholarly journals Effects of aqueous plant extracts and inorganic fertilizer on the germination, growth and development of maize (Zea mays L.)

2014 ◽  
Vol 59 (3) ◽  
pp. 243-254 ◽  
Author(s):  
Kanayo Chukwuka ◽  
Maxwell Obiakara ◽  
Israel Ogunsumi
Keyword(s):  
Plant Extracts ◽  
Growth And Development ◽  
Tap Water ◽  
Germination Percentage ◽  
Distilled Water ◽  
Aqueous Extracts ◽  
Radicle Growth ◽  
Randomized Design ◽  
Npk Fertilizer ◽  
Completely Randomized Design

Screen house experiments were carried out to examine the effects of aqueous leaf extracts of Tithonia diversifolia (Ti) and Vernonia amygdalina (Ve), as well as NPK fertilizer (15-15-15) on the germination, growth and development of maize. Fresh leaves were collected, washed with tap water, chopped and pounded, soaked in distilled water and filtered. The two filtrates were used to prepare extracts at 50 and 100% w/v. Four maize seeds were placed in Petri dishes laid out in a completely randomized design with five replicates. In every Petri dish 10 ml of extract per treatment was added. A control experiment with distilled water was also set up. Also, in a completely randomized design with four replicates, 4-week-old potted maize plants were treated with 500 ml of each extract as well as with 1.52 g of NPK fertilizer. The results showed that the germination percentage of the seeds followed the order Ti50 - Control - Ve50. The seeds treated with aqueous extracts of T. diversifolia and V. amygdalina at 100% w/v produced lower but equal germination percentage. The seedling radicle growth was significantly inhibited by the aqueous extracts of Ti100, Ve50 and Ve100 (p?0.05). The inhibition was dose-dependent and more pronounced in seeds treated with extracts of V. amygdalina. The aqueous extract of T. diversifolia (50% w/v) and control influenced radicle growth substantially. All the extracts inhibited the plumule development compared to the control. On the other hand, growth, development and yield were not significantly affected by the plant extracts.

scholarly journals Virucidal effect of chlorinated water containing cyanuric acid

1988 ◽  
Vol 101 (3) ◽  
pp. 631-639 ◽  
Author(s):  
T. Yamashita ◽  
K. Sakae ◽  
Y. Ishihara ◽  
S. Isomura ◽  
H. Inoue
Keyword(s):  
Cyanuric Acid ◽  
Tap Water ◽  
Swimming Pool ◽  
Inactivation Rate ◽  
Inhibitory Influence ◽  
Distilled Water ◽  
Swimming Pool Water ◽  
Virucidal Effect ◽  
Time Required ◽  
Effect Of Chlorine

SUMMARYThe inhibitory influence of cyanuric acid on the virucidal effect of chlorine was studied. The time required for 99·9% inactivation of ten enteroviruses and two adenoviruses by 0·5 mg/l free available chlorine at pH 7·0 and 25○C was prolonged approximately 4·8–28·8 times by the addition of 30 mg/l cyanuric acid. Comparative inactivation of poliovirus 1 by free available chlorine with or without cyanuric acid revealed the following. The inactivation rate by 1·5 mg/l free available chlorine with 30 mg/l cyanuric acid or by 0·5 mg/l free available chlorine with 1 mg/1 cyanuric acid was slower than by 0·5 mg/1 free available chlorine alone. Temperature and pH did not affect the inhibitory influence of cyanuric acid on the disinfectant action of chlorine. In the swimming-pool and tap water, cyanuric acid delayed the virucidal effect of chlorine as much as in the ‚clean’ condition of chlorine-buffered distilled water. The available chlorine value should be increased to 1·5 mg/l when cyanuric acid is used in swimming-pool water.

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