Showing papers on "Distilled water published in 1969"

Antagonistic Effect of Monovalent Cations in Maintenance of Cellular Integrity of a Marine Bacterium

Abstract: The susceptibility of a marine bacterium, designated isolate c-A1, to lysis in distilled water and in salt solutions has been found to be a function of Na(+) concentration Optical densities of cells pre-exposed to 005 m MgCl(2) were maintained in 10 m KCl, whereas those of cells pre-exposed to 10 m NaCl were not maintained at any KCl concentration tested Cells transferred from MgCl(2) to low concentrations of NaCl underwent more extensive lysis than did those transferred to distilled water The degree of disruption of cells transferred to distilled water from mixtures of 005 m MgCl(2) and NaCl (0 to 10 m) was dependent on the concentration of NaCl; similar results were obtained with LiCl, but not with KCl In electron micrographs of thin sections, c-A1 cell envelopes consisted of two double-track layers which fractured and peeled apart on lysis after pre-exposure to NaCl-MgCl(2) mixtures Envelope eruptions or "hernias" occurred only in lysed cells pre-exposed to NaCl alone No evidence for a functional lytic enzyme was found Comparative studies on a terrestrial pseudomonad with a multilayered envelope indicated that preexposure to NaCl did not enhance the susceptibility of this cell to lysis in distilled water The lytic susceptibility of the marine bacterium is considered to be the consequence of competition between specific monovalent cations and Mg(++) for electrostatic interactions with components of the cell envelope of this organism

Patch testing with potassium dichromate in different vehicles.

Abstract: Occlusive patch tests were used on 46 chromium-hypersensitive patients to determine the threshold of sensitivity for chromium in distilled water, in alkaline buffer solution (pH 12), and in petrolatum. Chromium in alkaline solution was the most sensitive test method (mean threshold 0.08%), then came chromium in petrolatum (0.15%), and, finally, chromium in distilled water (0.27%). Percutaneous absorption studies on guinea pigs showed increased absorption of chromium from alkaline solutions compared with the two other vehicles. We consider that this condition is probably the cause of the greater sensitivity when patch testing with chromium in alkaline solution.

Concentration Effect on Odor Addition or Synergism in Mixtures of Methyl Sulfide and Tomato Juice

Abstract: SUMMARY: The effect of various concentrations of tomato juice and methyl sulfide (Me2S) in triple distilled water on threshold values of the juice-Me2S mixtures was studied on juices prepared from five varieties of canning tomatoes. When Me2S and tomato juice were diluted to less than 10 ppb and 1,000 ppm respectively, before mixing, no significant interaction between juice and Me2S was observed in the juice-Me2S mixture. The odor intensities of the two components (as measured by threshold values in distilled water) were additive at subthreshold concentrations. As the concentrations of juice and Me2S were increased before mixing, an increasing degree of interaction or synergism was observed in the mixture. At concentrations of 105 ppm juice and 1 ppm Me2S odor intensity of the mixture was approximately double that which would be expected on an additive basis. However, this may not be a case of true synergism if the concentrations which give rise to the effect produce other products of lower threshold values.

Precipitate Flotation of Complexed Cyanide

Abstract: Precipitated cyanide, complexed with Fe(II) at a molar Fe/CN ratio of 0.550, can be floated readily from aqueous suspension with a cationic surfactant, ethylhexadecyldimethylammonium bromide. The effects of three distinct mixing times of significance in preparing the precipitate and contacting it with surfactant, of pH, of initial cyanide concentration, of initial surfactant concentration, and of ionic strength have been established experimentally. Mixing times and the initial cyanide concentration have little influence on the flotation, while increases in pH and ionic strength have a most pronounced influence, part of which can be overcome with increased surfactant concentrations. At pH 6.0, 95% of the complexed cyanide can be foam separated from distilled water suspensions 1.5 to 3.1 mM in total cyanide. About 0.04 mole surfactant/mole complexed cyanide is required; about 0.08 mole/mole is required to increase the flotation to 99% or to overcome ionic strength effects.

Hydrogen sulfide odor threshold

Abstract: tration at which the odor of hydrogen sulfide in water can be detected, the following technique was used. Ten wide-mouth glass-stoppered jars of 1 -liter capacity were partly filled with 800 ml of odor-free distilled water, containing sufficient sulfuric acid to lower the pH to about 4. The temperature of the water was about 25 °C. To five of these jars, equal quantities of a dilute sodium sulfide solution of

The effect of fluoride ingestion on the response of the rat to parathormone and calcitonin.

Abstract: Long-term ingestion of 100 p.p.m. of fluoride as NaF in the drinking water of the intact growing rat resulted in a slight but significant decrease of fasting plasma calcium concentration when compared with that in controls given distilled water. The plasma calcium response of both groups of rats to administered calcitonin was similar. The effect of parathormone on the plasma calcium response of thyroparathyroidectomized rats given NaF or distilled water showed a similar degree of hypercalcemia. Intact rats receiving fluoride or distilled water, given the same amount of parathormone, exhibited only a slight elevation of plasma calcium which was similar in both groups. It is concluded that the long-term ingestion of fluoride probably does not alter the response of the growing rat to endogenous or exogenous parathormone or calcitonin.

A volumetric determination of sulphate in sea water

Abstract: : Titration of sulfates by means of an aqueous alcoholic solution of BaCl2 using Thorin as indicator, has been adapted to sea-water analysis. Cationic interference has been eliminated by passing the sample, diluted with twice distilled water, through a cation-exchange resin column. Chloride interference has been compensated by standardizing the titrant solution with a solution of H2SO4 containing HCl at a concentration corresponding to the chlorinity of standard sea water. The SO4/Cl ratios of 41 samples collected in various areas of the Mediterranean Sea have been evaluated. (Author)

The flame-photometric determination of calcium in solutions of high sodium content.

Abstract: A method is describeds for the flame-photometric determination of 0 to 50 p.p.m. of calcium in solutions containing 4 per cent. w/w of sodium. Calcium is adsorbed from 100 ml of solution on a column of sodium-form Chelex-100 chelating resin; sodium is selectively eluted with hydrochloric acid at pH 2·4. Adsorbed calcium is eluted with 2 N hydrochloric acid and the resin washed with distilled water. The eluate and washings are diluted to 100 ml and the calcium determined on a Unicam SP900 flame photometer.Magnesium, zinc, nickel, barium, mercury, manganese, copper and iron, present separately in concentrations of 25 p.p.m. or collectively in concentrations of 5 p.p.m. each, do not interfere. Aluminium depresses the amount of calcium found.The method has been used to determine calcium in simulated sea water.

A preliminary comparative assessment by activation analysis of some of the materials and containers used in pharmaceutical manufacture

Abstract: Neutron activation analysis has been used in a preliminary, comparative assessment of some of the materials and containers employed in pharmaceutical manufacture. Microgram and submicrogram amounts of manganese, copper, and sodium have been determined in water distilled and redistilled from stainless steel and pyrex glass stills. The leaching of these elements by distilled and doubly distilled water from stainless steel, pyrex glass, and polyethylene storage containers has also been studied. The Mn, Cu, and Na contents of polyethylene bottles were also determined. The same techniques were used to determined these impurities as well as As, Au, and Sb in adrenaline and vitamin C.

A new technique for the economic production of cellulase.

Abstract: 3 cellulolytic fungal cultures i.e., Pestalotiopsis westerdijkii, Sporotrichum pruinosum and Trichoderma viride were grown on wheat bran medium repeatedly and the crude enzyme was extracted with distilled water. The active cellulase present in the culture extract was precipitated by ammonium sulphate (saturation 80%) and dissolved in one-tenth volume of distilled water which was used as enzyme sample for the assays. The efficiencies of the concn. crude enzyme samples to hydrolyse various pure cellulosic substrates were studied. The different components of the enzyme samples obtained from the second series showed increased activity compared to the other 2 series. The results of these findings are discussed.

Sucrose and water consumption by rats exposed to gamma-neutron radiation

Abstract: : This study examined the possible use of sucrose and water as reinforcers in behavioral studies of rats, after low dose gamma-neutron irradiation. Twenty-four rats were offered a choice of a 10 percent sucrose solution of distilled water ad libitum. Another 24 rats received only distilled water. Of the 24 rats in each of the above groups, three subgroups of six rats each received 120, 260 or 520 rads of mixed gamma-neutron radiation. The fourth subgroup of six rats was sham irradiated. Two days after irradiation, the subgroups that had been offered sucrose and water developed a significant aversion to the sucrose solution, and simultaneously increased their consumption of water. The subgroups receiving only distilled water decreased their consumption by the second day postirradiation. The most significant decrease in water consumption was observed in the rats receiving water only and 520 rads of radiation. The results suggest that the changes in consumption of sucrose and water caused by irradiation eliminate their use as reinforcers in behavioral experiments with radiation.

Effect of restoration of body fluid on food and water intake in water deprived rats

Abstract: After rats were deprived of water for 21-1/2 hours, one of the following 14 treatments was given to each subject: intraperitoneal injection of 2,4,6, or 8 cc of water, 2, 4, 6, or 8 cc of 0.45 per cent NaCl solution, or 2, 4, 6, or 8 cc of 0.9 per cent, NaCl solution; or one of two control conditions which consisted of sham injection or a 30-minute period with free access to water. Thirty minutes following the treatment either food or water was presented for one hour to assess the effects of the treatment. This period was followed by a one-hour recovery period during which both food and water were provided. The results indicated that injection of isotonic saline failed to either reduce water intake or increase food intake beyond the sham control level, but injections of distilled water and hypotonic saline altered water and food intake in proportion to the amount injected. Overall, injection of 0.45 per cent saline was half as effective as water injec­ tion on both food and water intake. The complex thirst induced by water deprivation was not reduced by extracellular volume restoration. The conclusion was reached that intracellular hydration is necessary to reduce the complex thirst which subsequently induces appetite for food.

Set/Supercontraction Characteristics of Oxidized Wools Setting of Oxidized Wool in Distilled Water

Abstract: This paper reports changes in the set/supercontraction characteristics of wool fibers, after certain step-wise modifications using the oxidizing agents iodic acid, periodic acid, and perchloric acid. An attempt is made to analyze these data in the light of the existing knowledge of the modern wool-setting theory.