Effect of potassium

The effect of potassium nitrate on the rate arises in a similar way. The concentration of nitrate ions in concentrated nitric acid is appreciable, and addition of small quantities of nitrate will have relatively little effect. Only when the concentration of added nitrate exceeds that of the nitrate present in pure nitric acid will the anticatalysis become proportional to the concentration of added salt. 

TABLE 3.4 The effects of potassium nitrate on rates of nitration in nitromethane... 

Fig. 10. Effect of potassium on SO2 removal where (—) represents the NSPS limit, and (V) represents LMF4-T, ( ) LMF4-U, and ( ) LMF4-V.

The template effects of potassium and lithium ions are responsible for the efficiency of the synthesis of macrocyclic ligands in 18-CROWN-6 and2,2.7,7,12,12,17,l 7-OCTAMETHYL-21,22,23,24-TETRAOXAPER-HYDROQUATERENE. 

Fig. 8. The effect of potassium intercalation on the temperature dependence of the resistivity of a bulk SWCNT sample. Curve a, pristine material from a different batch than in Fig. 6 curve b, after doping with potassium curve c, after heating in the cryostat vacuum to 580 K overnight curve d, after 3 days at 580 K [35].

The effect of potassium methanoate on arsenic pentafiuoride does not represent any danger provided the solvent used is trichlorotrifluoroethane. Every time benzene is used instead of the halogenic solvent, a large number of detonations have been reported. 

Only limited information is available on effects of potassium (K) supply on root exudation. Increa.sed exudation of sugars, organic acids, and amino acids has... 

E. Slesak and J. Jurek, Effects of potassium humate on electric potentials of wheat roots. Acta Univ. Wrati.sl. 37 13 (1988). 

Figure 1. Composition and Concentration Effects of Potassium Based Clear Well Fluids on Core Permeabilities.

Table IV. Effect of Potassium Salts on Conventional Drilling Muds...

Kharab P, Singh I. 1985. Genotoxic effects of potassium dichromate, sodium arsenite, cobalt chloride and lead nitrate in diploid yeast. MutRes 155 117-120. 

Parasympathetic stimulation causes a decrease in heart rate. Acetylcholine, which stimulates muscarinic receptors, increases the permeability to potassium. Enhanced K+ ion efflux has a twofold effect. First, the cells become hyperpolarized and therefore the membrane potential is farther away from threshold. Second, the rate of pacemaker depolarization is decreased because the outward movement of K+ ions opposes the effect of the inward movement of Na+ and Ca++ ions. The result of these two effects of potassium efflux is that it takes longer for the SA node to reach threshold and generate an action potential. If the heart beat is generated more slowly, then fewer beats per minute are elicited. 

Wesner, D. A., Linden, G., and Bonzel, H. P. 1986. Alkali promotion on cobalt Surface analysis of the effects of potassium on carbon monoxide adsorption and Fischer-Tropsch reaction. Appl. Surf. Sci. 26 335-56. 

Arakawa, H., and Bell, A.T. 1983. Effects of potassium promotion on the activity and selectivity of iron Fischer-Trospch catalysts. Ind. Eng. Chem. Res. Process. Des. Dev. 22 97-103. 

Raje, A.P., O Brien, R.J., and Davis, B.H. 1998. Effect of potassium promotion on iron-based catalysts for Fischer-Tropsch synthesis. J. Catal. 180 36-43. 

Miller, D.G., and Moskovits, M. 1988. A study of the effects of potassium addition to supported iron catalysts in the Fischer-Tropsch reaction. J. Phys. Chem. 92 6081-85. 

Chen, X., Knight, D. P., Shao, Z. Z., and Vollrath, F. (2002). Conformation transition in silk protein films monitored by time-resolved Fourier transform infrared spectroscopy Effect of potassium ions on Nephila spidroin films. Biochemistry 41, 14944-14950. 

Ellison, A.C. and Maren, T.H. (1972). The effect of potassium metabolism on acetazolamide-induced teratogenesis. Johns Hopkins Med. J. 130 105-115. 

The brief survey of various catalysts for the isomerization of vinylnorbomene 408 into ethylidenenorbomene 394 as well as the effectiveness of potassium amide in liquid ammonia for this purpose were described (equation 192)250. One step in the synthesis... 

H. Tanaka, S.-I. Ito, S. Kameoka, K. Tomishige, and K. Kunimori, Promoting effect of potassium in selective oxidation of CO in hydrogen-rich stream on Rh catalysts, Catal. Commun. 4, 1-4... 

Liu D, McAdoo D. 1993. An e3q)erimental model combining microdialysis with electrophysiology, histology, and neuro-chemistry for exploring mecahnisms of secondary damage in spainal cord injury effects of potassium. J Neurotrauma 10(3) 349-362. 

Shalaby, A.R. and El-Rahman, H.A. (1995). Effect of potassium sorbate on the development of biogenic amines during sausage fermentation. Die Nahrung., 39, 310. 

The effects of potassium hydroxide are similar to those of other strong alkalies such as sodium hydroxide. The greatest industrial hazard is rapid tissue destruction of eyes or skin on contact either with the solid or with concentrated solutions. Contact with the eyes causes disintegration and sloughing of conjunctival and corneal epithelium, corneal opacification, marked edema, and ulceration. After 7-13 days, either gradual recovery begins or there is progression of ulceration and corneal opacification, which may become permanent. If potassium hydroxide is not removed from the skin, severe burns with deep ulceration will occur. 

Ni(lOO) reduces the degree of backdonation and results in a blue-shift in the v(CO) frequency. We have carried out a detailed FTIR investigation of the complex effect of potassium and chemisorbed oxygen on the adsorption of CO on Ni(KX)) [32]. In brief, the 2090,2013 and 1898 cm-i features in Figure 7b are related to the adsorption of CO on Ni sites which are non-uniformly modified by the coadsorbed potassium and atomic oxygen [32]. In addition, the 2134 cm-i feature in Figure 7b can be assigned to the adsorption of CO on the Ni2-n sites of NiO clusters that are not modified by the presence of potassium. 

Electrodeposition on Zn Electrodes Rezaite and Vishomirskis [209, 210] have investigated the effect of potassium cyanide on the electrodeposition of zinc from zincate solutions on the Zn electrode. It is known that cyanide added to the zincate solution led to high-quality zinc coatings. The presence of KCN decreased the limiting current of Zn(II). 

Walker, W.M., D.W. Graffls, and C.D. Faulkner. 1987. Effect of potassium and boron upon yield and nutrient concentration of alfalfa. Jour. Plant Nutr. 10 2169-2180. 

To investigate the effect of potassium on the analysis of sodium by atomic emission spectrometry. 

The effect of potassium. Take five replicate emission readings of each of the six potassium standards. Remember to zero the instrument between each standard while aspirating a blank. Calculate the mean emission and RSD for each standard and plot a graph of sodium emission intensity against potassium concentration. The RSD is defined as standard deviation (s) of the emission intensities divided by the mean emission intensity (jf)[RSD = (s/x) x 100]. 

In pacemaker cells (whether normal or ectopic), spontaneous depolarization (the pacemaker potential) occurs during diastole (phase 4, Figure 14-1). This depolarization results from a gradual increase of depolarizing current through special hyperpolarization-activated ion channels (If, also called If,) in pacemaker cells. The effect of changing extracellular potassium is more complex in a pacemaker cell than it is in a nonpacemaker cell because the effect on permeability to potassium is much more important in a pacemaker (see Effects of Potassium). In a pacemaker—especially an ectopic one—the end result of an increase in extracellular potassium is usually to slow or stop the pacemaker. Conversely, hypokalemia often facilitates ectopic pacemakers. 

---