Potassium results

Tire reduction of TAF 100 by metallic potassium resulted in the formation at room temperature of the stable anion radical 109, which yielded a simple nine-line ESR pattern caused by the two sets of two equivalent nitrogens with Ani = 3.40 and An2 = 0.81 G (79JOC3211).Tlie nonequivalency of the nitrogens was explained by the association of the potassium cation with one of the two diazacylopentadienyl moieties (Scheme 44). 

Many layered solids form intercalation compounds, where a neutral molecule is inserted between weakly bonded layers. For example when potassium vapour reacts with graphite above the melting temperature of potassium (337 K), it forms a golden compound KCs in which the potassium ions sit between the graphite layers, and the inter-layer spacing is increased by 200 pm (Figure 3.16). Addition of a small amount of KO2 to the molten potassium results in the formation of a double layer of potassium atoms between the graphite layers and a formula close to KC4. 

While the action of carbon monoxide upon heated potassium results in the formation of the carbonyl, moist carbon dioxide reacts with the metal to form carbonate and formate ... 

Figure 8.15 Comparison of radial distributions of oxygen atoms conditional on the simplest metal ions in typical aqueous solutions obtained by ab initio molecular dynamics (AIMD). See Asthagiri etal. (2004c) for details. The potassium result was presented by itself in higher detail in Fig. 7.7, p. 157. Notice that the lithium result (displaced vertically by 2) and the sodium result (displaced vertically by 1) have inner shells clearly defined on the basis of the g r). For lithium, the occupancy of that inner shell is almost exclusively 4. For sodium, the principal occupancy is 4, but there is a statistical admixture of another oxygen that also serves to blur the primary minimum this occupancy is indicated by 4-1. For potassium, this statistical characterization is 4 - 2, as was also shown differently by Fig. 7.7 this leads to the occultation of the principal minimum in that case.

Treatment of the diester (671) with styrene oxide and 0.1 mole equivalent of potassium resulted in the formation of (672). Larger quantities of potassium gave the imidazole derivative (673) via an imidazo[5,l-c][l,4]oxazine intermediate (75JCS(P1)798). 

Hypertension is often treated with diuretics. Diuretics are drugs that promote the Joss of sodium from the body, though some diuretics can cause the loss of potassium, resulting in hypokalemia. The use of dietary supplements of K to correct this hypokalemia has been shown to be of benefit and to result in decreases in blood pressure. The best source of potassium is plant food, as is strikingly apparent from the data in Table IG.l however, the interest in nonfood supplements of potassium continues. One problem with potassium salts is that they taste bad and can produce nausea. Hence, there has been some interest in the manufacture of aesthetically acceptable forms of potassium salts. One form, a mixture of NaCl and KCl, is useful for those who feel compelled to add sodium chloride to their food. One study revealed that NaCI-KCl mixtures are accepted and their use can result in a reduction of sodium intake. The study, which involved normotensive subjects, did not lead to any consistent change in blood pressure (Mickeisen rt nI., 1977). 

Beta-blockers can prolong and possibly exaggerate the rise in serum potassium resulting from the injection of suxamethonium (SEDA-10, 108) (SEDA-11, 122) (175,176). 

Potassium ions exert a direct, stimulatory effect on aldosterone secretion that is independent of the renin-angiotensin system. Small increases in serum potassium elicit a rise in serum aldosterone levels, whereas small decreases in serum potassium result in reduced levels of serum aldosterone. Aldosterone, by promoting the... 

The coupling of a flow injection system to FAAS for potassium resulted in a much smaller standard deviation than if a continuous flow FAAS system was applied. In CRM 408 and even in CRM 409 the latter system worked closer to its limit of determination. 

Decreased activity of the enzyme sodium potassium ATPase increases cellular sodium and decreases potassium, resulting in a decreased potential difference across the cell membrane. Because cellular sodium gain exceeds potassium loss, the cell water content increases. The decreased enzyme activity and the derangement in cell sodium, potassium, and water content are corrected partially by hemodialysis and completely by renal transplantation (C22, P3). 

Glycosides increase intracellular sodium and also extracellular potassium by inhibitory actions on sodium potassium ATPase. Thus, with chronic therapy, because intracellular sodium is increased, phase 0 may be blunted slightly. The increase in extracellular potassium results in a decrease in the rate of repolarization and thus a decrease in the slope of phase 3 of the action potential, and a skewed appearance. This results in a longer time for the membrane to repolarize and, accordingly, an increase in the effective refractory period. Because the objective of the drug is to increase the influx of calcium, the faster influx of calcium results in a shortened phase 2, because a shorter time is required for the membrane to reach the equilibrium potential for calcium. Finally, phase 4 is elevated and increased in slope, due to the alterations in sodium and potassium concentration. This, with chronic therapy, and particularly as toxicity is approached, results in delayed oscillatory afterpotentials (see Figure). 

Alcohols when treated with Group I metals like sodium and potassium result in alkoxides. 

A rapid increase in potassium resulting in excess can result in cells becoming hyperexcitable, leading to cardiac arrest, whereas a slow rise in potassium to excessive levels will cause a depression of action potentials and neuromuscular reactivity. 

The addition of potassium results in a significant increase in the induction time for methane decomposition, as shown in Figure 5.6 [415]. This implies a retarding role of potassium on the dissociation of methane and the nucleation of carbon (refer to Chapter 6). 

As already explained, the renal response to loss of extracellular fluid volume results in a low plasma potassium concentration. As shown in Figure 3.8B, the lowering of the extracellular concentration of potassium results in an increased potassium concentration gradient from intra- to extracellular fluid. Consequently, potassium difl uses from the intracellular to the extracellular compartment. To maintain electrochemical neutrality, hydrogen ions move in the opposite direction, from extracellular to intracellular fluid. The extra-... 

The effect of added metallic potassium is similarly observed with respect to the isotopic equilibration of N2 on Ru/AC [97] as well as on pure ruthenium [50]. The addition of metallic potassium results in about a 500 fold increase in the activity of Ru at 673 K, while the increase in the ammonia synthesis rate is less extensive (25 fold), due to the inhibition by the presence of hydrogen (cf. Sections 3.3.2, 3.3.3.1) [98]. The inhibition by hydrogen is accounted for by the competitive adsorption of hydrogen as well as by a decreased adsorption constant for N2 [86, 98]. 

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