• Asian-Australasian Journal of Animal Sciences
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• v.6 no.1
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• pp.99-105
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• 1993

This study determined the macro-mineral levels in plants and sheep, at different times during the year, at three farms in northern China. Samples of plants, animal tissues and faeces were collected at 5 to 8 times during the year from each site. They were analysed for calcium, sodium, phosphorus, magnesium and potassium. Sodium concentrations in plants were below those recommended for optimum animal production at all sites for all or part of the year (0.01-1.66 g/kg DM). Low concentrations of sodium in faeces were measured and signs of sodium deficiency (soil ingestion) were observed on one farm. There were seasonal trends in other mineral levels in plants and animals. Plants were lowest in potassium (2.3-13.4 g/kg DM), magnesium (1.28-4.82 g/kg DM) and phosphorus (0.24-1.62 g/kg DM) in winter and spring. However, high levels of these elements were supplied in the feed supplements used at this time of the year. During the periods of rapid pasture growth, in summer and autumn, supplements of feed and salt are often not provide even though pasture concentrations of phosphorus and sodium are low. It may be at these times that sheep will be most susceptible to deficiencies of these elements.

• Environmental Analysis Health and Toxicology
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• v.25 no.3
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• pp.223-228
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• 2010

Neocaridina denticulata is a small freshwater shrimp indigenous to Korea. As an indigenous species has long-adapted to particular water environments, the species can be a suitable indicator to assess environmental risks caused by hazard chemicals in the particular site. Thus Neocaridina denticulata, a small freshwater shrimp indigenous to Korea, is worth considering for a test species for such purpose. N. denticulata were exposed to pentachlorophenol sodium salt, sodium azide and potassium dichromate using automatic flow-through system for 96 hours. The 96 hr lethal concentrations ($LC_{50}$) of these chemicals were calculated as $0.53{\pm}0.09\;mg/L$, $2.40{\pm}0.61\;mg/L$ and $1.21{\pm}0.09\;mg/L$ respectively and showed relatively small deviation from repetitive test results. When compared with the toxicity values of other species for each chemical, N. denticulata had moderate or high sensitivity to the toxicity of these chemicals. It can be concluded that N. denticulata is a good test species to evaluate acute toxicity of various hazardous chemicals.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.433-436
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• 2008

Deterioration in the concrete structure are due to carbonation, chloride ion attack and frost attack. Therefore, concrete structure is needed to surface protection for increase durability using silicate impregnants. Thus, this study is concerned with self-cleaning and durability of silicate hydrophilic impregnants of concrete structure using lithium and potassium silicates. From the experimental test results, lithium and potassium silicates have a good properties as a carbonation resistance. Lithium and potassium silicates make good use of hydrophilic impregnants of concrete structures.

• Cement Symposium
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• no.11
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• pp.27-32
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• 1983

• The Korean Journal of Physiology
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• v.8 no.1
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• pp.55-65
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• 1974

The effect of ginseng on the ATPase activity of rabbit ref cell membrane has been investigated. The experiments were also designed to determine whether the components of ginseng could be attributed to the effect on ATPase activity which dependent upon sodium plus potassium and is sensitive to ouabain. The following results were observed. 1. The activity of the $Na^{+}-K^{+}-ATPase$ from red cell membrane is stimulated by ginseng, and the concentration of ginseng for half-maximal activity is about 15 mg%. The pH optimum for the ginseng sensitive component is 7.6. 2. The portion of the enzyme activity stimulated by ginseng is completely abolished by ouabain. 3. The activating effect of ginseng on the ATPase, with a given concentration of sodium in the medium, is increased by raising the potassium concentration but activity ratio is decreased. 4. The activating effect of ginseng on the ATPase, with a given concentration of potassium in the medium, is increased by raising the sodium concentration but the activity ratio is decreased. 5. The ATPase activity is increased by small amounts of calcium but inhibited by larger amounts and the rate of activity by ginseng is constant. 6. The action of ginseng on the ATPase activity was not related to the sulfhydryl group of cysteine, the amino group of lysine, the imidazole group of histidine, the quanidinium group of arginine, the carboxyl group of aspartic acid, or the hydroxyl group of threonine. 7. The activating effect of ginseng on the ATPase activity may be not due to a saponin which is contained in ginseng.

• The Korean Journal of Physiology
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• v.10 no.1
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• pp.25-34
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• 1976

The action of serotonin on the sodium plus potassium activated ATPase activity in the rabbit red cell membrane has been investigated. The experiments were also designed to determine the mechanism of action of serotonin on the ATPase activity. The following results were obtained. 1) The NaK ATPase activity of rabbit red cell ghosts is stimulated by low concentration of serotonin but inhibited by higher concentration, and the concentration of serotonin for maximal activity is about 2mM. The pH optimum for the serotonin sensitive component is 8.0. 2) The activating effect of serotonin on the ATPase, with a given concentration of sodium in the medium, is increased by raising the potassium concentration but the ratio of activity is decreased. 3) The activating effect of serotonin on the ATPase, with a given concentration of potassium in the medium, is increased by raising the sodium concentration but the ratio of activity is decreased. 4) The ATPase activity is increased by small amounts of calcium but inhibited by larger amounts and the ratio of activity by serotonin is decreased by small amounts of calcium but increased by larger amounts. 5) The action of serotonin on the ATPase activity was not related to the amino group of lysine, the hydroxyl group of threonine, the carboxyl group of aspartic acid, or the imidazole group of histidine. 6) The action of serotonin on the ATPase activity is due to sulfhydryl group of the enzyme of NaK ATPase.

• Journal of Nutrition and Health
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• v.26 no.9
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• pp.1118-1128
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• 1993

This study was undertaken to investigate the acute effect of caffeine consumption on the change of mineral concentration in serum and urinary mineral excretion in healthy young females. On two separate mornings at one week intervals, each subject drank a coffee which contained no caffeine and 3mg/kg body weight caffeine. To obviate dietary effects on mineral concentration in serum and urine, each subject fasted at least ten hours before consuming the test beverage. At one, two, three and four hours, serum and urine production collected seperately for measurement of sodium, potassium, calcium, phosphorus and magnesium concentration. The results were as following : 1) Mean age of subjects was 20.6$\pm$0.32, Mean body mass index of subjects was 21.64$\pm$0.89, which was within $\pm$10% of ideal body weight. 2) Total urine volume of caffein groups for 4 hour after caffeine consumption was higher than that of decaffeine one, but urine pH was unchanged after caffeine consumption. Total urinary four hour excretion of creatinine was not affected by caffeine consumption and creatinine clearance also was not different from the control value. 3) In serum, mean three hour content of sodium(p<0.01) and phosphorus was higher in the subject given the caffeine. Mean serum magnesium and calcium contents were lower in caffeine group than that of decaffeine one. Mean serum magnesium content for three hour after caffeine ingestion was affected by caffeine consumption(p<0.001). Mean serum content of potassium was unaffected by caffeine consumption. 4) Total urinary four hour excretion of sodium, increased significantly after caffeine consumption(p<0.05), while total urinary four hour excretion of potassium, calcium, phosphorus and magnesium was unchanged after caffeine intake. Urinary excretion of Na, Ca, P and Mg was greatest at one hour after caffeine consumption, especially urinary sodium and potassium excretion was significantly high(p<0.05, p<0.01). The above results show that only 3mg caffeine per kg body weight increase the urinary macro mineral excretion in healthy young females.

• Journal of Nutrition and Health
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• v.16 no.3
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• pp.209-215
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• 1983

In high sodium societies, the incidence in blood pressure with childhood growth is more abrupt than the rate of rise in low sodium populations. Thus, it appears that a lower level of dietary sodium intake is required to correct established hypertension and to prevent its appearance In present work, an investigation was made to estimate the correlation between urinary sodium, potassium and creatinine excretion, weight, height, upper arm circumference, blood pressures and the number of heart rate. Sixty- four children aged 12-16 years (41 boys and 23 girls) were measured. Twenty -four-hour urinary sodium and potassium excretion averaged 132.8 mEq and 42.1 mEq in boys, 126.4 mEq and 41.3 mEq in girls. Twenty- four -hour urinary creatinine excretion averaged 795.7 mg and 744.3mg in boys and girls, respectively. Systolic and diastolic blood pressure were 117.6mmHg and 49.7mmHg in boys, 95.5mmHg and 58.2mmHg in girls. Systolic blood pressure correlated positively weight, height and urinary creatinine but diastolic blood pressure correlated positively with upper arm circumference and negatively with urinary potassium. It was concluded that urinary sodium does not explain the blood pressure.

• Korean Chemical Engineering Research
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• v.50 no.5
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• pp.789-794
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• 2012

For the purpose of development of the latex suitable for polymer cement mortar, experiments on the preparation of carboxylated styrene butadiene latex by the method of the two-step emulsion polymerization were performed. Methyl methacrylate, methacrylic acid and acrylic acid were selected as carboxylic co-monomer, styrene and butadiene as monomer, sodium dodecylbenzene sulfonate and sodium salt of lauryl sulfonate as anionic emulsifiers, and nonylphenoxy poly (ethyleneoxy) ethanol (n=10, 20, 40) as latex stabilizer. Potassium persulfate and sodium bisulfite were also used as redox initiator, and sodium monohydrogen phosphate and potassium carbonate as electrolytes. The effects of categories and concentration of carboxylic co-monomer, molecular weight control agent, crosslinking agent, and styrene/butadiene monomer ratio on the characteristics of latex were investigated. Polymerization recipes for preparation of polymer cement mortar could be proposed. The prepared latexes were tested for the physical properties such as compressive and flexural strength when latexes were mixed with cement mortar. The results showed that the latex could be adapted to polymer cement mortar. Also, it was recognized that the compressive and flexural strength were exhibited 25.4% and 45.3% respectively higher improvement than the quality standards at 28 days curing time.

• The Korean Journal of Ecology
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• v.6 no.2
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• pp.90-97
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• 1983

Seasonal changes of the soil nutrient contents and aboveground biomass, relationship between the soil nutrients and the productivity, and the net efficiencies of solar energy conversion were studied in two reeed communities (Phragmites communis Trin.) at the salt marsh in the estuary of the Sumjin-River from April 30 to October 9, 1981. The inorganic nutrients such as exchangeable sodium and potassium of soil were decreased during growing season. The amounts of organic matter, exchangeable sodium and potassium, total nitrogen, and available phosphorus in stand $\prod$ were much more than those of stand $\coprod$ . Productivity of Phragmites communis was positively correlated with the soil nutrients such as available phosphorus, exchangeable potassium and total nitrogen. The maximum dry matter productions of the aboveground parts in stand $\prod$ stand $\coprod$ were $ 1, 120g/m^2; and; 843g/m^2$ in August, and the net coversion efficiencies of PhAR based on growing season (April to September) were 1.77% and 1.33%, respectively.