• Applied Biological Chemistry
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• v.15 no.2
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• pp.143-162
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• 1972

Based on the concentration of $^{40}K$ naturally occurring radioisotope of potassium, a method for the determination of total potassium in soils and plants was developed. The method was extended to evaluate the potassium supplying power of soils by taking the ratio of exchangeable potassium to total potassium $(K_{ex}/K_t)$, termed the potassium buffering capacity. Using this as index, it was observed that the release of potassium from soil fellows the from order reaction. A linear relationship was found between the potassium buffering capacity and the release constant of potassium or mica content of the clay. Similarly the potassium buffering capacity was also closely correlated with total uptake of potassium by rice plant. Hence it is concluded that the method for determining of the potassium buffering capacity could be veil applied to characterize the potassium availability of soils. The method for the determination of potassium is characterized by (1) The efficient measurement of the weak beta activity emissions from the samples, (2) identification of $^{40}K$, (3) calculation of total potassium content using the proportional constant of $^{40}K$ of samples to that of the standard. Difference in the potassium supplying power of soils due to soil types was also evaluated with the use of this technique. The degree of the potassium supplying power was in the order of soil types as red-yellow podzolic and lateric soils, basaltic materials(Rvd)> low-humic gley and alluvial soils, alluvial plains and food plains(Apa)> low-humic gley soils, nearly level to sloping local alluvial plains and slopes(Afb)> low-humic gley and alluvial soils, fluvio-marine plains (Fma).

• Asian-Australasian Journal of Animal Sciences
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• v.1 no.1
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• pp.33-41
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• 1988

In a study about minerals cycling in grassland agro-ecosystem, investigation on relations among two minerals, potassium(K) and magnesium(Mg), and nitrogen(N) was performed. Four kinds of diets different in K and N levels were fed to four goats with a Latin-square method and $2{\times}2$ factorial design. As the basal diet, press cake silage prepared from Italian ryegrass was used because of its uniformity and comparatively low mineral concentrations. Supplementation of K and N were made using potassium bicarbonate and urea. In the experiment, it was clearly shown that high K concentration in the forage crops is the main reason of the low utilization of Mg in ruminant animals. However, high nitrogen intake resulted in the increase of magnesium retention, urinary potassium excretion, water intake and volume of urine and in the decreases of potassium intake minus urinary potassium excretion. The results of high nitrogen intake seemed to be produced in the following order;increase of urine, increase of water intake, increase of urinary potassium excretion, and decrease of intake minus urinary potassium excretion. The amount of potassium intake minus urinary potassium excretion had significantly close relationships with magnesium utilization and serum magnesium concentration. As a conclusion, higher nitrogen intake by ruminants seemed to be preferable for magnesium utilization through increased water intake and urinary potassium excretion, if the sufficient drinking water could be supplied to ruminants.

• Applied Chemistry for Engineering
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• v.8 no.3
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• pp.410-415
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• 1997

Fibrious potassium hexatitanate whisker was produced from the calcination process using a mixture of the natural rutile ore and industrial $K_2CO_3$. Fibrous Potassium titanate was prepared by the following procedures the starting material consisting of $K_2O{\cdot}4.4TiO_2$ was calcined at $1050^{\circ}C$ for 3 hrs. The calcined products obtained under the above condition consisted mainly of potassium hexatitanate with a small admixture of potassium dititanate and potassium tetratitanate. Therefore the single phase of potassium hexatitanate was obtained by heat treatment of $850^{\circ}C$, 3 hrs.

• Journal of Nutrition and Health
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• v.24 no.4
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• pp.344-349
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• 1991

This study was undertaken to evaluate the potassium consumption and excretion in forty healthy male workers of a tire company in Seoul. Mean postassium intake for three days in the subject was $54.5\pm16.7mEq/day(2.13\pm0.64g)$ and urinary excretion of potassium in 24 hours was $45.9\pm10.5mEq(1.77\pm0.41g)$. Thus 83% of dietary potassium was excreted in the form of urine. Dietary ratio of Na to K was $4.15\pm0.58$ while urinary ratio of Na to K was $5.20\pm1.11$. The main food source of potassium was cooked rice with soybean in the rice group, potato with soybean paste soup in the part of soup group. and seasoned Spanish mackerel with raddish in the side dish group. There was a strong correlation between dietary protein and dietary potassium(r=0.694, p<0.001). Urinary sodium and potassium were also strongly associated with each other(r=0.647, p<0.001).

• Journal of Chest Surgery
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• v.15 no.1
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• pp.35-39
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• 1982

Cold blood potassium cardioplegia, by two types of the infusion systems, was used in 45 patients who were undergone the open cardiac operation. Method A [in 25 patients] was the syringe infusion system and method B [in 20 patients] was the pump infusion system. Cold blood potassium cardioplegic solution was used less amount on method B than method A. Serum potassium was often increased significantly on method A as a result of excessive infusion of cold blood potassium cardioplegic solution. But method B, excessive infusion of cold blood potassium cardioplegic solution was prevented by reperfusion of the previous infused cold blood potassium cardioplegic solution through the recirculation system. Alteration of infused rate and concentration of potassium in cold blood potassium cardioplegic solution during infusion [which might be suggested on the method A] could be controlled on method B.

• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.64-73
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• 2001

Generally potassium in the soil can be remained as water soluble, exchangeable, and available types, respectively. Theses types of potassiums are also known to keep their kinetic relationships to each other. The Purpose on this research was to investigate types and relationships of potassium in the soil, and the characteristics of potassium supply in different forest soils. The results could be summarized as follows; 1. The amounts of available potassium in A and B horizon soils by continuous leaching with 0.01N-HCl were as follows : for A Horizon soils, pohang(Gray brown forest soils), Changsung (Brown forest soils), and Youngwol(Dark red forest soils) were ranged from 0.2me/l00g to 0.8me/100g, Taean(Red and Yellow forest soils) was 0.1-0.6me/100g, Kapyung(Brown forest soils) was 0.2-0.4me/100g. For the B layer, Youngwol was 0.1-0.5me/100g, Pohang, Taean, Kapyung were 0.1-0.4me/100g, Changsung was 0.1-0.3me/100g, respectivly. 2. Of ten times-pulse leaching with 0.01N-HCl for A layer soil, more 80% of total available potassium leaching were recovered by the second pulse as leachate for Pohang, Changsung, Youngwol, while similar amounts of potassium in the leachate were obtained with the third pulse leaching for Kapyung, Taean, respectively, On the other hand, the 80 % release of available potassium from the B layer soil was obtained by the second pulse leaching for all areas investigated. 3. For the relationships between soluble potassium and exchangeable potassium, the exchangeable potassium was increased while the soluble potassium was not changed significantly in B layer. And both soluble potassium and exchangeable potassium in A layer were similar. For the relationship between exchangeable potassium and available potassium in both A and B layers, the amounts of available potassium increased by 1.2 to 1.5 times as the exchangeable potassium increased. 4. For distribution of all types of potassium throughout locations investigated, the types of potassium were in the decreasing orders of available, exchangeable, and soluble. 5. The simplified method for an analysis of all types of potassium by sequential leaching with 0.01N-HCl should be developed not only with respect to time-saving and efficiency but also verification of the relationship between available potassium and tree growth.

• Journal of Yeungnam Medical Science
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• v.11 no.2
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• pp.363-374
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• 1994

The purpose of this study was to investigate the characteristics or the potassium channels existing in the rat urinary bladders. Smooth muscle strips of rat detrusor urinae were examined by isometric myography. Relaxation responses of detrusor muscle strips to the three potassium channel openers pinacidil, a cyanoguanidine derivative, BRL 38227, a benzopyran derivative and RP 52891, a tertrahydrothiopyran derivative were examined. The potassium channel openers reduced the basal tone, and the rank order of potency was RP 52891>pincidil>BRL 38227. Procaine, an inhibitor of the voltage-sensitive potassium channel tended to increase the basal tone, but it did not affect the relaxant effects of the calcium-activated potassium channel opener did not antagonize the relaxant effects, but it reduced the Emax of RP 52891 and BRL 38227. Glibenclamide, an inhibitor of the ATP-sensitive potassium channel, antagonized the relaxant effects of pinacidil, RP 52891 and BRL 38227 reducing the Emax of RP 52891 and BRl 38227. Galanin which inhibits secretion of insulin through opening the ATP-sensitive potassium channels in pancreatic ${\beta}$-cells rather increased the basal tone of the isolated detrusor strips. These results suggest that the urinary bladder of the rat has mainly the ATP-sensitive, glibenclamide sensitive potassium channel, which is a different type from that in the pancreatic ${\beta}$-islet cells..

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.1
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• pp.145-150
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• 1992

To determine the effect of dietary potassium and lysine levels on blood parameters, serum and bone composition, 360 male broiler chicks of 3 days of age were used in a completely randomized $3{\times}3$ factorial experiment for 6 weeks. Experimental diets contained three supplemented levels of dietary potassium (0.3, 0.6 and 1.2%) and three supplemented levels of dietary lysine (0.6, 1.2 and 2.4%). Dietary levels of potassium and lysine did not influence blood pH, $pCO_2$, $pO_2$, $HCO_3$ and total $CO_2$ and interaction between potassium and lysine was not shown (p > 0.05). Serum lysine and arginine contents were significantly different by the levels of dietary lysine (p < 0.05). Lysine-arginine antagonism was observed in high lysine diet. But increasing dietary potassium did not alleviated the lysine-arginine antagonism. Serum sodium, potassium and chloride were not affected by dietary potassium and lysine levels (p > 0.05). Femur weight, length and P contents were affected by the levels of dietary lysine (p < 0.01). But no difference was observed in femur ash and Ca contents (p > 0.05). Interaction between potassium and lysine was shown in ash and P contents (p < 0.01).

• Journal of Chest Surgery
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• v.17 no.4
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• pp.587-592
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• 1984

Potassium cardioplegia for myocardial preservation is being used extensively in open heart surgery. This study was designed to investigate the change in serum and urine potassium before, during, after the administration of cold blood potassium cardioplegic solution containing 28-30 mEq/L [28.6\ulcorner.56 mEq/L] of potassium chloride in 6 dogs. Total potassium dose used in the study was 14.9\ulcorner.89 mEq/L [1.2 mEq/Kg]. Mean potassium level in serum was within normal limits. Urinary excretion of potassium decreased during bypass but increased after bypass and eventually exceeded the amount of potassium infused as cold blood potassium cardioplegic solution. While cold blood potassium cardioplegia is a safe and efficient method of myocardial protection, postoperative potassium level must be observed carefully in order to detect obligatory potassium excretion following open heart surgery.

• Asian Journal of Turfgrass Science
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• v.25 no.2
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• pp.190-194
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• 2011

Potassium (K) is one of the essential nutrients for plants but is not a constituent of any plant compound. K is substances for activation of many enzymes and influences the process that the enzymes are involved in catalyzing. Although experimental results associated with the K effects with both benefits and no effects on turfgrass growth were reported, the limited research results of K effects on turfgrass among K sources are available in Korea. The objectives of the study was conducted to evaluate responses of Kentucky bluegrass (Poa pratensis L.) treated by fertilizer treatments with six K sources. There were six fertilizer treatments as K sources applied to Kentucky bluegrass which were potassium nitrate (13-0-44, PN), potassium chloride (0-0-60, PC), potassium sulfate (0-0-50, PS), polymer-coated potassium sulfate (0-0-45, PPS), potassium thiosulfate (0-0-25, PT), and potassium sulfate granulated with methylene urea (20-0-25, PSU). Potassium of $8g\;m^{-2}$ and N of $5g\;m^{-2}$ was applied 4 times giving a total 20 and $30g\;m^{-2}$, respectively. Although significant differences were found for turfgrass color, quality, chlorophyll index, and clipping dry weight, no consistent results among K sources were found during the one year study. Overall, K treatments didn't affect turfgrass growth in this study.