Showing papers on "Potassium nitrate published in 1986"

Method of forming an improved hydrophilic coating on a polymer surface

Abstract: A method of forming an improved hydrophilic coating by applying on a non-reactive hydrophilic polymer surface layer an osmolality-increasing compound to produce a more stable hydrophilic surface and to produce a more slippery surface in wet condition. The polymer surface layer is treated with a solution having above 2% (weight/volume) of an osmolality increasing compound and then the solvent of the solution is evaporated. Osmolality increasing compounds are nontoxic organic or unorganic salts other than trihalogenids, mono- or di- saccharides or sugar alcohols. Preferred compounds are glucose, sorbitol, sodium chloride, sodium citrate, sodium bensoate, calcium chloride, potassium chloride, potassium iodide, potassium nitrate. The solution of the osmolality increasing compound contains preferably a polymer. Medical articles treated with the solution of osmolality increasing compounds according to the method above also relate to the invention.

Thermodynamics of multicomponent, miscible ionic systems: the system lithium nitrate-potassium nitrate-water

Abstract: Pressions de vapeur des systemes KNO 3 −H 2 O et LiNO 3 −KNO 3 −H 2 O de 373 a 436 K Calcul des activites de l'eau Proprietes thermodynamiques d'exces calculees a partir du modele

Sublimation sources for nitrous acid and other nitrogen compounds in air

Abstract: Sources of nitrous acid and nitric acid in air in the parts-per-billion concentration range are provided by means of room-temperature oxalic acid sublimation onto solid sodium nitrite and potassium nitrate, respectively. Nitrogen dioxide is not present and nitric oxide is present only at a small percentage in the nitrous acid source at relative humidities in the 30-60% range. The presence of nitrous acid is verified by spectroscopic and chemical reaction studies. Nitric oxide, hydrogen cyanide, and other compounds can be similarly produced with appropriate target compounds. Nitrogen dioxide from permeation devices must be used in plastic systems to minimize impurities.

Precipitation incidence of the lanthanoid(III) hydroxides

Abstract: The precipitation pH values of fourteen lanthanoid (III) hydroxides were determined. The hydroxide ion was supplied electrolytically in aqueous solutions of potassium nitrate, and the formation of the insoluble hydroxide was detected through the optical scattering method. The precipitation pH values ranged from 7.47 to 5.74 between lanthanum and lutetium. Discussions are made in connection with some inherent values of the lanthanoid metal ions.

Electrodes in series. Simultaneous flow injection determination of chloride and pH with ion-selective electrodes

Abstract: Chloride and pH can be determined simultaneously by flow injection potentiometry with a series electrode arrangement at a rate of 60 samples per hour, with a standard deviation of 1.5% for chloride and 1% for pH. Samples (30 µl) are injected into a carrier buffer solution (pH 7.6) containing 0.5 mol dm–3 of potassium nitrate and 10–2 mol dm–3 of sodium dihydrogen phosphate as an ionic strength adjustment buffer. The sample-buffer zone formed is transported through a laboratory-made coated tubular solid-state chloride-selective electrode via a glass membrane micro pH combination electrode on to the reference electrode (for chloride). The method is suitable for the determination of chloride in the range 20–5000 mg dm–3 and a pH range from 3 to 10.

Studies on polytetrafluoroethylene latices Part 3. Electrophoretic mobility in univalent electrolytes

Abstract: The electrophoretic mobilities of particles of polytetrafluoroethylene (PTFE), prepared by a dispersion polymerisation technique using a peroxyacid initiator, have been determined using a mass transport technique. Investigations were carried out as a function of sodium chloride concentration at pH 9 and as a function of pH in the presence of various salts, namely, sodium chloride, potassium nitrate and potassium thiocyanate. The particles were found to have a low surface charge density, consistent with the idea that sparsely distributed charged sites originated from initiator fragments leaving the major part of the surface in a hydrophobic condition. Below a pH of ca. 4.5 increases of mobility with decreasing pH were observed with chloride and thiocyanate as the anion. These were attributed to an anion adsorption process, dependent on thepKa of the surface groups, and a model for the process is described.

Effects of fertilisers on vegetable production 2. Effects of nitrogen fertilisers on nitrogen content and nitrate accumulation of spinach and beetroot

Abstract: The effects of 5 different nitrogenous fertilisers (ammonium sulphate, ammonium sulphate + N-serve, potassium nitrate, poultry manure, and urea) each at 5 application rates (0, 150, 300, 450, or 600 kg N/ha) on the total nitrogen (N) and nitrate content of 2 varieties of spinach (Spinacea oleracea L.) and 1 variety of beetroot (Beta vulgaris L.) were evaluated in a pot experiment using Wakanui silt loam soil. The nitrification inhibitor, N-serve, was used to retard the microbial conversion of ammonium to nitrate. Total N and nitrate N generally increased with increasing rates of N applied. Potassium nitrate application resulted in the highest N uptake levels, and poultry manure application gave the lowest. N-serve depressed N uptake at 600 kg N/ha applied. Plants accumulated nitrate to a level potentially hazardous to health at only the highest rate (600 kg N/ha) of potassium nitrate, ammonium sulphate, and urea applied. Differences between the 2 varieties of spinach tested were not significant.

Coordination chemistry of alkali and alkaline earth cations. X-ray structural analysis of bis (benzo-15-crown-5) potassium nitrate monohydrate

Abstract: The 1:2 charge separated KNO3 complex with benzo-15-crown-5 (B15C5) has been crystallized from a 50% water-methanol solution. K(B15C5)2NO3·H2O is monoclinic,P21/c,a=12.717(2),b=19.569(2),c=13.025(3) A, β=100.79(1)o,Z=4,D c =1.37 g·cm−3. The X-ray structure was refined toR=0.052 for 3049 independent reflections withF 0 2 ≥2.0σ(F 0 2 ), collected with MoK α radiation for a 2 θ-range of 4–44°. The K+ ion is coordinated tenfold in a crown sandwich through all five oxygen atoms of the macrocyclic ligand. Nitrate and water oxygens are not involved in the cation coordination sphere.

Gaseous nitrogen losses from fertilized soil during nitrification and denitrification using the acetylene blockage technique

Abstract: A sandy soil amended with different forms and amounts of fertilizer nitrogen (urea, ammonium sulphate and potassium nitrate) was investigated in model experiments for N2O emission, which may be evolved during both oxidation of ammonia to nitrate and anaerobic respiration of nitrate. Since C2H2 inhibits both nitrification and the reduction of N2O to N2 during denitrification, the amount of N2O evolved in the presence and absence of C2H2 represents the nitrogen released through nitrification and denitrification. Results show that amounts of N2O-N lost from soils incubated anaerobically with 0.1% C2H2 and treated with potassium nitrate (23.1 µg N-NO 3 − /g dry soil) exceeded those from soils incubated in the presence of 20% oxygen and treated with even larger amounts of nitrogen as urea and ammonium sulphate. This indicates that nitrogen losses by denitrification may potentially be higher than those occurring through nitrification.

Tracer-diffusion of cobalt ions in sodium and potassium nitrates in agar gel

Abstract: Tracer-diffusion of Co2+ ions is studied in agar gel in the presence of sodium and potassium nitrates at 25°C. The diffusion coefficient values at various electrolyte concentrations are compared with the corresponding theoretical values computed on the basis of Onsager's theory. The deviations from the theory are attributed to the various co-occurring effects in the diffusion medium. The activation energy for the process of diffusion of Co2+ ions in presence of above electrolytes is also reported.

Burning Rate Studies of Energetic Double Base Propellants

Abstract: A systematic study was carried out on the combustion characteristics of CMDB propellants containing ammonium nitrate, ammonium perchlorate, potassium nitrate, potassium perchlorate, RDX and PETN. While ammonium and potassium perchlorates increased burning rates, other additives maintained either the same burning rate or reduced burning rates marginally. Propellants containing these additives showed marginally higher peak temperatures, indicating interaction among the species of double base propellant decomposition and those of additives.

Mirror polishing liquid for cdte wafer

Abstract: PURPOSE:To form a mirror surface, which has small waviness and the abnormal ity of the surface of which is reduced, by using a specific aqueous solution such as the aqueous solution of sodium hypochlorite and sodium hydrogencarbonate. CONSTITUTION:A polishing liquid is selected from groups consisting of the aqueous solution of sodium hypochlorite and sodium hydrogencarbonate, the aqueous solution of sodium hypochlorite and sodium hydrogencarbonate and sodium chloride, the aqueous solution of potassium dichlomate and nitric acid, the aqueous solution of potassium dichlomate and nitric acid and potassium nitrate, the aqueous solution of potassium dichlomate and sulfuric acid, and the aqueous solution of potassium dichlomate and sulfuric acid and potassium sulfate. A mirror surface, the waviness of the surface of which is reduced extremely and surface imperfections of which such as hazes, bits, etc., are minimized, is acquired by using these substances.

Chemical effectiveness of elastic and inelastic energy loss of He + , Ar + , and Xe + ions bombarding solid potassium nitrate

Abstract: Decomposition of crystalline potassium nitrate due to He+-, Ar+-, and Xe+- ion bombardment was studied in the energy range from 20 to 100keV. The cross sections for producing nitrite ions were for the first time determined to be 5.7×10−20m2, 12.6×10−20, and 22.0×10−20m2 for 100keV He+, Ar+, and Xe+ ion, respectively. Comparing the values of these cross sections with the rate of an elastic and inelastic energy loss of these incident ions, which were calculated on the basis of the theory of Lindhard et al., it may be concluded that inelastic energy is about five times more efficient than elastic energy for the decomposition of the solid potassium nitrate.

Influence of boron on nitrate reductase activity in roots of Zea mays

Abstract: Boron either enhances or decreases in vitro nitrate reductase activity in isolated root tips of Zea mays depending on nitrate supply and boron concentration. In media containing potassium nitrate (5 × 10−2 M KNO3) enzyme activity is increased depending on boron concentration; maximum nitrate reductase activity was reached at 10−7 M H3BO3. However, in the absence of nitrate this boron effect was not obvious. Large amounts of boron (10−1 M H3BO3) reduced enzyme activity drastically. Experiments with actinomycin D, chloramphenicol and cycloheximide suggest that the increase in enzyme activity by boron depends on de novo protein synthesis but does not require RNA synthesis.

Photoassisted Reduction of Carbon and Nitrogen Compounds with Semiconductors

Abstract: The conversion of visible light into the stored energy of chemical fuel was studied, using semiconductors as photosensitizers. The reactions investigated were the reduction of carbonate ions to organic compounds and of nitrogen oxyanions to ammonia. Using suspensions of CdS, ZnS-CdS or TiO2 in 1M KOH and 0.1M Na2S at 61° C, illuminated with a 150W Xe-lamp, we found that there was a slow release of ammonia, 0.014 micromol h−1 cm−2 (illuminated area) which was the same whether the mixture was purged with argon or nitrogen gas. Addition of 0.2M potassium nitrate did not change the rate of release of ammonia. However, addition of potassium nitrite caused a marked increase in the rate of production of ammonia. Using 0.13M potassium nitrite in 1M KOH, 0.1M sodium sulfide at 61° C, the production rate of ammonia was 0.97 micromol/(h cm−2) in the presence of TiO2 (70mg in 70ml reaction solution), 0.60 micromol/(h cm2) in the presence of CdS (same concentration), and 0.55 micromol/(h cm2) in the presence of ZnS-CdS (70mg – 50mg mixture). In the absence of sodium sulfide, and if sodium sulfite was substituted for sodium sulfide, the above photoassisted reduction of nitrite ions to ammonia was negligible. Also, there was no reaction in the dark. With CdS - ZnS in 0.5M potassium carbonate — 0.1M sodium sulfide, illumination caused the production of ammonia, methanol and formaldehyde, at rates of 7.1×10−9, 1.5×10−9 and 0.2×10−9 mol h2212; cm−2, respectively.

Thermodynamics of aqueous reciprocal salt systems. I: Relationships between the thermodynamic behaviour of molten and aqueous mixtures

Abstract: Etude de la variation de l'energie standard de Gibbs pour les reactions reciproques haute temperature: AX+BY=AY+BX

Nitrate-reducing bacteria in Kuwait domestic sewage.

Abstract: Domestic sewage in Kuwait is mainly treated by an activated-sludge process, where different effluents and sludges are separated. Nitrate reduction in the raw sewage, effluent-1 and effluent-2 were studied. Various enrichments of these sewage samples were effected using 0.2 mg/ml of nitrogen as potassium nitrate and/or 0.5% carbon as glucose. Addition of 0.2 mg/ml nitrate-nitrogen enhanced more ammonia production (117.6 micrograms/ml) in comparison with other enrichments to sewage samples. Nitrate-reducing bacteria were also at a maximum with nitrate enriched sewage samples, especially with effluent-1 (109 X 10(6)/ml). Escherichia coli and Klebsiella pneumoniae were the only two nitrate-reducing bacteria found in all sewage samples tested. Nitrite was unstable during the 7 days incubation period under anaerobic conditions which suggests that nitrates are reduced to ammonia.

Hexanitrotetrachloroazobenzene and method of preparation

Abstract: 2,4,6,2',4',6'-Hexanitro-3,5,3',5'-tetrachloroazobenzene, a new, high melting explosive is prepared by the simultaneous nitration and oxidation of 3,5-dichloroaniline in strong or fuming sulfuric acid using fuming nitric acid or potassium nitrate as both oxidizing and nitrating agent. Under these conditions nitric acid or potassium nitrate is expected to be a nitrating agent only, and oxidation of the amino group is not expected.

Method of complex production of sodium bifluoride, active sodium fluoride, hydrogen fluoride and potassium nitrate

Abstract: A complex method was developed for the conversion of an ammonium fluoride solution and an ammonium fluoride/potassium fluoride solution into sodium bifluoride, active sodium fluoride and hydrogen fluoride, with potassium nitrate as a co-product and a concentrated solution of ammonium nitrate as a by-product. Quickly settling crystals of sodium bifluoride containing a very small amount of water after centrifugation are obtained with high efficiency from the reaction which occurs during the mixing of a concentrated solution of sodium fluoride in aqueous nitric acid with the ammonium fluoride solution. The by-product of the reaction is a very concentrated solution of ammonium nitrate. Potassium nitrate is precipitated from the ammonium fluoride/potassium fluoride solution after the addition of ammonium nitrate and after cooling. The mother solution formed in the crystalization is applied to the precipitation of sodium bifluoride. The production of hydrogen fluoride and active sodium fluoride takes advantage of the technically known thermal decomposition of sodium bifluoride as obtained according to the invention. Active sodium fluoride and hydrogen fluoride can be produced in different ratios, since either product of the thermal decomposition of sodium bifluoride may be partially applied to the precipitation of additional sodium bifluoride.

Effect of Radiation Dose on Formation & Annealing of Different Damage Fragments in Potassium Nitrate

Abstract: Despite extensive work 1 B on the radiolytic decomposition of alkali metal nitrates 1 11, wherein NO;, 0 and O2 are the primary radiolytic products, a clear cut mechanism is yet to be established. It is seen that oxygen remains trapped':" in the lattice as molecular oxygen upto about 22 % decomposition on irradiation at room temperature. Further the G-value for the decomposition of potassium nitrate varies with temperature and also with % decomposition at a particular temperature+":". The slope of the plot of nitrite ion formation as a function of dose changes abruptly at some point below 2 % decomposition 1 and upto 22 % decomposition, the yield of the nitrite ion is independent of the intensity but dependent upon the amount of nitrate present.: Many workers2.4,B,J 0.11 have reported an increase in apparent nitrite yield, determined by eerie method of analysis as compared to that determined by conventional Shinn method. This discrepancy is attributed to the presence of small amount of reducing species other than NO;. The present note deals with the effect of radiation dose on the formation and thermal recovery of total reducing species, (NO; r and nitrite, NO; in v-irradiated potassium nitrate. Crystals of potassium nitrate (AR, BDH) were dried at 383K and stored over phosphorus pentoxide before use. Glass ampoules containing the samples and sealed in vacuo were irradiated with Co-60 Y-rays at room temperature. The dose rate was 0.102 MGy hr 1, as determined 12 using Fricke dosimeter, taking G (Fe3 +) = 15.5. Crystals were exposed to different doses between 0.05 and 2.00 MGy. Nitrite was estimated by the diazo colour reaction of Shinn 13as modified by Kershaw and Chamberlin+f.Tn eerie analysis, irradiated crystals were dissolved in 2 x 10-4 M Ce4+ in 0.4 M H2S04 and the absorbance at 330 nm was compared with that of a reagent blank