Showing papers on "Potassium nitrate published in 1999"

Action potential conduction block of nerves in vitro by potassium citrate, potassium tartrate and potassium oxalate

Abstract: . Objectives: potassium salts in desensitising formulations are believed to act by blocking nerve conduction. The aim of this study was to assess the ability of some organic potassium salts to block action potential conduction and to compare their effects with potassium chloride and potassium nitrate. Materials and methods: potassium citrate, oxalate or tartrate were added to Krebs’ solutions to raise the potassium concentration to 8–64 mM. The test solutions were applied to rat spinal nerves in a bath while monitoring the compound action potentials evoked by electrical stimulation. Results: all potassium salts attenuated the compound action potential in a dose-dependent manner. There were no significant differences between the effects of potassium tartrate and potassium citrate solutions (p>0.1) which caused significantly greater compound action potential attenuation than the same concentrations of potassium oxalate (p oxalate>chloride=nitrate. Conclusion: potassium citrate were: and potassium tartrate were more effective than other potassium salts in blocking nerve conduction and may be more effective dentinal desensitising agents.

Factors governing the electrochemical synthesis of α-nickel (II) hydroxide

Abstract: The electrodeposition of α-nickel hydroxide is promoted by the simultaneous chemical corrosion of the electrode by an acidic nitrate bath. Chemical corrosion results in the formation of a poorly ordered layered phase which is structurally similar to α-nickel hydroxide and provides nucleation sites for the deposition of the latter. Therefore under conditions which enhance corrosion rates such as low current density (<1.3 mA cm−2), high temperature (60 ∘C), high nickel nitrate concentration (≥ 1M) and the resultant low pH (∼1.7), α-nickel hydroxide electrodeposition is observed, while β-nickel hydroxide forms under other conditions. Further, α-nickel hydroxide deposition is more facile on an iron electrode compared to nickel or platinum.

Vapor-phase reactions of catechol with dimethyl carbonate. Part III: Selective synthesis of veratrole over alumina loaded with potassium nitrate

Abstract: Alumina loaded with potassium nitrate has a very high catalytic activity for the vapor-phase methylation of catechol with dimethyl carbonate to selectively afford veratrole. Thus, veratrole was obtained in a 97% yield at 583 K. The reaction pathway includes both guaiacol and catechol carbonate as intermediates.

Determination of Mass Transfer Coefficients for Crystal Growth of Nitrate Salts

Abstract: In this paper, the crystal growth of sodium nitrate and potassium nitrate from aqueous solutions, in a perfectly stirred batch crystallizer, has been studied considering the effect of temperature, supersaturation degree, and the size of seed crystal growth rate. The mass transfer coefficients obtained correlated with Re, Sc and NL dimensionaless numbers. Supersaturation curve determination using a 0.5 mW He-Ne laser, connected to an automated data acquisition system, was the first stage of the study. The supersaturation and saturation curves were closely parallel with average DT value of 4.1 and 6.8 °C for KNO3 and NaNO3 respectively. For the growth kinetics order, unit values were found for both salts, with diffusion as a controlling stage.

Desensitizing bleaching gel

Abstract: A substantially anhydrous gel useful for bleaching teeth comprising: (i) at least 25% by weight of organic polyol; (ii) less than 3% by weight polyacrylic acid thickening agent; (iii) at least 10% by weight carbamide peroxide (or a chemically equivalent amount of another bleaching agent, such as 3% by weight hydrogen peroxide); (iv) neutralizing agent; (v) chelating agents; (vi) desensitizing agent; and (vii) miscellaneous ingredients such as Cirtoxain® and flavorants. The organic polyol is preferably glycerin. The polyacrylic acid thickening agent is preferably a carbomer. The desensitizing agent is preferably potassium nitrate, strontium chloride, potassium citrate, strontium nitrate, or a similarly effective alkali or alkaline earth metal salt of an organic or inorganic acid.

Phase Modification of Ammonium Nitrate by Potassium Salts

Abstract: Modification of the room temperature phase (IV-III) of ammonium nitrate (AN) has been attempted using a variety of potassium salts namely, KF, KCl, KI, KNO3, K2CO3, K2SO4, KSCN and K2Cr2O7. No phase transition was observed when AN containing 1-2% by mass of these potassium salts is heated from room temperature (25 degrees C) onwards in DTA and DSC scans, but the linear expansion due to phase transition was still observable in TMA measurements. Complete arrest of the linear expansion occurs only when a higher concentration of the additive is used. Similarly, in thermal cycling experiments, complete phase modification in the temperature range -80 to 100 degrees C occurs only with a higher percentage of the potassium salt. The extent of modification, however, is found to be dependent both on the concentration, and the type of the anion. Potassium dichromate when used as an additive modifies the phase as well as the decomposition pattern of AN.

Molecular Aggregates of Nitrate Ion with the Tetravalent Lewis Acid Host 12-Mercuracarborand-4: Novel Trihapto Coordination of NO(3)(-).

Abstract: The host−guest complex [(C2B10H10Hg)4(NO3)2(H2O)][K(18-crown-6)]2(H2O)(CH3)2CO, 1, was formed from the reaction of 12-mercuracarborand-4 with 2 equiv of potassium nitrate/18-crown-6, while [(C2B10H10Hg)4(NO3)2][K(18-crown-6)]2, 2, was found to be the preferred product in the reaction of 12-mercuracarborand-4 with 3 equiv of potassium nitrate/18-crown-6. Both were isolated in almost quantitative yield from their respective reaction mixtures. The title complexes were characterized by multinuclear NMR spectroscopy, negative-ion FAB mass spectroscopy, and X-ray crystallography. In complex 2, the two bonded nitrate ions are each η3-coordinated with the oxygen atoms bonded face-on to the four Hg atoms of the planar host molecule.

Fire extinguishing agent of aerosol

Abstract: A fire-extinguishing agent of aerosol is prepared from potassium nitrate and/or sodium nitrate as oxidant (50-70 Wt.%), the polycarbon alcohols chosen from the alcohol with 6 or more carbon atoms andhigh-molecular compound containing amino as incendiary agent (20-30 Wt.%), the mixture of ferrocene and potassium sulfate as compound catalyst (2-10 Wt.%)and curing-forming aid (5-20 Wt.%). Its advantages include high fire-extinguishing efficiency and speed, no damage to humanbody, animal, matter and ozonosphere, no explosion, and good physical and chemical stabilities.

Raw coal treating agent

Abstract: The raw coal treating agent consists of sulfur-fixing agent, swelling agent, catalyst and oxidizing agent,and its adding quantity is 25%-4% of raw coal weight Said raw coal treating agent contains 76%-82% of powdered sulfur-fixing agent with grain size of 1 mm-6mm, 10%-13% of swelling agent which can be sodium chloride, potassium nitrate, sodium nitrate and calcium carbonate, 2%-3% of catalyst which can be ironic oxide, manganese dioxide, chromic oxide and cobaltous oxide and 5%-7% of oxidizing agent which can be potassium permanganate, potassium chlorate, potassium nitrate and sodium nitrate The above-mentioned sulfur-fixing agent contains 70%-85% of calcium oxide and 15%-30% of calcium carbonate, sodium carbonate and magnesium oxide It also possesses adhesive which can be paper-making waste liquor, aluminium-making waste slag or soap-making waste residue Its sulfur-fixing efficiency can be up to 70%, and the dust discharge also can be reduced

Fire suppressant compositions

Abstract: Fire suppressant compositions which are substantially free of ammonium nitrate and which comprise potassium nitrate in an amount sufficient to generate at least about 10 wt. % potassium carbonate when combusted. Most preferably, a guanidine salt, such as guanidine nitrate, is used in combination with the potassium nitrate. The compositions employed in the present invention have low pressure exponents, high burning rates and low flame temperatures.

Efeito de fertilizantes nitrogenados na produtividade de melão

Abstract: A study was carried at Petrolina-PE, Brazil, with the melon crop (Cucumis melo L.), cv. Valenciano Amarelo, in a Red-Yellow Latosol with the objective of evaluating the effect of nitrogen fertilizers sources and their combinations, applied through the conventional way and through water irrigation during the crop cycle. The experimental design was a split block with four replica- tions and nine treatments: 1. control (without N); 2. urea; 3. ammonium sulphate, both applied con- ventionally; 4. urea applied up to 42 days after germination; 5. ammonium sulphate applied up to 42 days after germination; 6. urea applied up to 15 days and potassium nitrate from 16 to 42 days after germination; 7. urea applied up to 15 days and ammonium sulphate from 16 to 42 days; 8. urea applied up to 30 days and potassium nitrate from 31 to 42 days, and 9. urea applied up to 15 days, ammonium sulphate from 16 to 30 days and potassium nitrate from 31 to 42 days, at the level of 80 kg/ha of N. The fertilizers used during the crop cycle (treatments 4 to 9) were applied through irrigation water. It was found that urea applied through fertirrigation up to 42 days provided higher yield (31.14 ton/ha), not differing, however, from the other treatments, with the exception of the control and ammonium sul- phate, which gave the lowest yields (25.06 and 24.65 ton/ha, respectively). It was found a variation in fruit mean weight from 1.63 to 1.84 kg/fruit. There was no significant difference in total soluble solid content ( o Brix ) among the treatments.

The effect of KNO3 application on the yield and fruit quality of olive

Abstract: Seventy two percent of olive soils in Turkey are low in potassium and thirty two percent of the olive trees in the same region are insufficient in K nutrition Moreover, 52 % of these soils are high in Ca Potassium application to these olive groves is quite rare and generally in the form of compound fertilizers

Application of Raman in phase equilibrium studies: the structures of substitutional solid solutions of KNO3 by RbNO3

Abstract: Raman spectroscopy was employed to investigate the KNO3-RbNO3 system Raman studies indicated that Rb+ may substitute K+ up to 67 mol % in the solid solutions of the KNO3 II structure (denoted as K1 − x RbxNO3 (KII)) and up to 80 mol % in the solid solutions of the KNO3 III structure (denoted as K1 + x RbxNO3 (KIII)) The substitutional crystals retained the transitions of I to III to II of KNO3 on cooling and the metastable property of KNO3 III at room temperature It was found that rubidium nitrate had a considerable tendency to have the structure of potassium nitrate This accounts for the fact that larger rubidium ions can replace many more smaller potassium ions in the nitrate than vice versa When the concentration of rubidium ions was more than 67 mol %, the substituted crystals underwent the mixed structural phase transition of the KNO3 III structure to the RbNO3 IV structure, and K1 − x RbxNO3 (KIII) seemed to consist of disordered R3m microstructure

Effects of foliar potassium nitrate and calcium nitrate application on nutrient content and fruit quality of fig

Abstract: The research work is carried out to investigate the effects of foliar potassium and calcium nitrate applications on nutrient content and fruit quality of figs. The trial was performed as three replications on Sanlop trees, the main cultivar for commercial drying. The foliar fertilisation was made twice on July 10 and 25, 1997, and the program was carried out as potassium nitrate at 3.0 % level, calcium nitrate at 1.5 and 3.0 % levels and a combined application of 2.0 % potassium nitrate and 2.0 % calcium nitrate. The results put forth an increase of K and Ca contents of leaf lamina and petiole. Applications exerted marked effect on fruit width, length, shape and width of the ostiolar opening. Similar consequences appeared on texture and sugar fractions as fructose, α-glucose, β-glucose and galactose of dried fruits.

Latent heat storage material composition for ice heat storage system

Abstract: PROBLEM TO BE SOLVED: To obtain a latent heat storage material which can repeat freeze and melting without encountering the precipitation and settlement of an inorganic salt and can be dispensed with agitation in the heat storage tank by using an aqueous solution containing a normally water-soluble polysaccharide, having a specified or higher viscosity and having a total content of a freezing point depressant for water equal to or lower than the eutectic concentration of the system. SOLUTION: The viscosity of the aqueous solution is 50 mPa.s or above at 25 deg.C. The polysaccharide used may be one having a solubility of 1 g in 100 ml of water at ordinary temperature. Especially, a polysaccharide which assumes nonionic when dissolved in water is desirable, and more particularly, hydroxyethylcellulose or guar gum is desirable. It is desirable that the amount of the water-soluble polysaccharide added is at most 10 wt.% based on the total weight of the heat storage material. The freezing point depressant for water may be anything that is used in an aqueous solution of an ice heat storage system and is desirably sodium nitrate, potassium nitrate, sodium chloride, potassium chloride, ammonium chloride or the like.

Extinguishing agent for extinguishing fires comprises potassium nitrate or potassium perchlorate, hydrogen-soluble fuel, and combustion rate regulator

Abstract: The extinguishing agent forming an aerosol comprises 65-80 wt.% potassium nitrate or potassium perchlorate, 10-12 wt.% hydrogen-soluble fuel and 21-8 wt.% combustion rate regulator. An Independent claim is also included for the manufacture of the extinguishing agent comprising inserting potassium nitrate or potassium perchlorate as oxidant into a mixer, adding the combustion rate regulator, and pouring in water and mixing to form a uniform moist homogenous composition. The hydrogen-soluble fuel is then added and mixed to form a uniform moist homogenous composition, dried and enclosed with a thin water-tight sleeve.

Rare earth energy-saving and sulfur-fixing agent

Abstract: The rare earth energy-saving and sulfur-fixing agent for fixing sulfur in coal and raising the combustion efficiency of coal consists of sodium chloride, sodium carbonate, sodium nitrate, potassium nitrate, lime powder, borax, ferric oxide, active carbon, magnesium oxide, potassium permanganate, non-toxic sludge from water treatment, mixed rare earth and dolomite powder. It has the advantages of adaptability to various kinds of coal with different sulfur content, sulfur-fixing temperature up to 400-1200 deg.c, SO2 removing rate up to 35-55%, inflammable volatile component reducing rate up to 45-55%, reducing residual inflammable matter in cinder by 10-15% and raising heat efficiency by 10-20%.

Gas generating agent composition for air bag

Abstract: PROBLEM TO BE SOLVED: To obtain a gas generating agent composition capable of readily handling, excellent in combustion efficiency and gas generating efficiency and reduced in residue producing amount in combustion by including carbon black or activated carbon and a phase-stabilized ammonium nitrate as essential components and as necessary further including an organic polymer-based binder, a molding auxiliary and a catalyst for reducing produced poisonous gas. SOLUTION: This gas generating agent composition consists essentially of 0.5-14 wt.% carbon black or activated carbon powder having 10-5,000 m /g specific surface area and 70-95 wt.% ammonium nitrate phase-stabilized by adding 1-15 wt.% at least one kind of compound such as potassium perchlorate, potassium nitrate or potassium chlorate to ammonium nitrate and as necessary, further contains <=12 wt.% organic polymer binder, <=2 wt.% molding auxiliary such as calcium (magnesium) stearate and <=2 wt.% catalyst for reducing poisonous produced gas such as copper oxide, iron oxide or zinc oxide.

Soil pollution by nitrates using sewage sludge and mineral fertilizers

Abstract: With the objective of evaluating soil pollution by nitrates, due to nitrogen leaching, several treatments using urban sludge and two mineral nitrogen fertilizers — ammonium sulfate applied as basic fertilization and potassium nitrate, applied by fertigation — were applied to fertilize cucumber plants (Cucumis sativus, L.). An alluvial soil was used; pH was 7.9 and its organic matter content was a middle value. Using fertigation (potassium nitrate), the best yield and the highest nitrogen use efficiency were obtained and only an insignificant amount of nitrogen was leached. Amounts of ammonium sulfate of 3.5 ton.ha−1 were toxic to the plants, and their nitrogen use efficiency was about 10%. On the other hand, the urban sludge treatment showed a nitrogen efficiency of 45% and there was practically not any nitrogen loss by leaching.

One-Step Synthesis of Alloxazines, Alloxazine-5-oxides, 5-Aryl-5-deazaalloxazines, and Fervenulin-4-oxides

Abstract: 1-Methylalloxazines and 1-methylalloxazine-N-oxides were prepared by the treatment of 1-methyl-6-anilinouracils with diethyl azodiformate (DAD) and potassium nitrate, and sulfuric acid in acetic acid, respectively. In addition, 1-methyl-5-aryl-5-deazaalloxazines were prepared by refluxing of 1-methyl-6-anilinouracils with aryl aldehydes in acetic acid. Treatment of 6-benzylidenehydrazinouracils with potassium nitrate and sulfuric acid in acetic acid gave fervenulin-4-oxides.

Yield response of polyethylene mulched tomato to potassium source and rate on sand

Abstract: Tomato (Lycopersicon esculentum Mill. cv. Sunny) was grown with the full‐bed polyethylene mulch‐seepage (modified furrow) irrigation system for three seasons to evaluate the effects of potassium (K) sources and K rates on fruit yields and leaf K concentrations. Soil in the experimental area was an Eau Gallie fine sand (sandy, siliceous, hyperthermic Alfic Haplaquods) that varied from 12 mg kg‐1 (very low) to 56 mg kg‐1 (medium) K by Mehlich I extraction prior to planting. Potassium sources, potassium chloride (KC1), potassium nitrate (KNO3), and potassium sulfate (K2SO4) were evaluated at 0, 90, 180, 270, and 360 kg kg‐1 K rates. Nitrogen (N) was applied at 270 kg kg‐1 and P at 43 kg kg‐1 with all K rates. Yields of extra‐large and marketable total yields in one season were higher (P<0.05) with potassium nitrate (KNO3) than with KC1. Maximum yields were produced from 270 to 360 kg K kg‐1, regardless of pre‐plant soil K concentrations. In the shoots, K concentrations increased with increasing K ra...

Method of making non-sag tungsten wire

Abstract: It has been discovered that potassium retention in NS tungsten processing may be improved by double doping tungsten blue oxide (TBO) prior to reduction. The novel `double-doping` process consists of dry doping standard singly doped K--Al--Si TBO with potassium nitrate, KNO 3 , followed by the standard reduction, acid washing, sintering, rolling and drawing steps. In another aspect, the novel method includes an aqueous extraction of heteropolytungstate anion [SiW 11 O 39 ] 8- from a sample of the singly doped tungsten blue oxide to predict potassium retention.

Some considerations about the use of carbon sources in jasmonic acid production.

Abstract: The effect of different carbon sources as sucrose, fructose, glucose and molasses were studied in relation to jasmonic acid production. The best results were obtained with a simple medium made up by final molasses, potassium nitrate and acid potassium phosphate, without the addition of other salts like Fe, Zn, Cu, Mo, etc. This alternative guaranteed a 100% increase in jasmonic acid production, compared to pattern medium, since a concentration of 2.08 g/l was obtained.