• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.279-281
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• 2002

The results of the specific radioactivity study for Rn-222 in mineral spring water of Khalzan mountain and Janchivlan of Mongolia, using the HP-Ge gamma-spectrometer, are discussed. Some physical and chemical properties in some sample of mineral spring water are determined.

• Korean Journal of Medicinal Crop Science
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• v.20 no.4
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• pp.251-258
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• 2012

The management and control of mineral nutrients is one of most important techniques to increase the productivity and the quality of Korean ginseng. The mineral nutrients are measured with different plant tissues and different growth stages of 2-year-old ginseng grown under hydroponic culture with two different temperatures. The content of N, P, Ca, and Mg were higher at low temperature in both leaves and roots than those at high temperature. However, the content of K was high in leaves at low temperature compared to that of high temperature, while it was not significantly different in roots. The uptake amounts of N and K was higher throughout the experimental period at low temperature in both leaves and roots than those at high temperature. However, the uptake amount of P was not clearly different between two different temperatures and among six different growth stages. The uptake amount of N, P, K was generally decreased in leaves from June to August, while it was increased in roots. The relationship between dry weight and mineral nutrients in leaves was appeared positive with N, K, Ca, and Mg, but negative P. In roots, N, K, Ca, and Mg were negative, showing that was positive with only P. Comparing the correlation coefficients among mineral nutrients in leaves, N and K were significantly positive correlation each other. P was significantly positive correlation with Na and Zn. In case of roots, N was highly significant positive correlation with K, Mg, and Mn, but P was negatively correlated with Ca, Cu, Na, Fe, and Zn.

• Journal of The Korean Society of Grassland and Forage Science
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• v.11 no.3
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• pp.189-194
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• 1991

This experiment was carried out to investigate the effect of pure mineral nitrogen fertilization on dry matter yield and to determine the amounts of advisable mineral nitrogen according to difference of annual precipitations in permanent grassland. The results obtained were as follows: 1. Only PK-fertilizing without additional mineral nitrogen application produced 6. 9 tonlha of annual dry matter yields on average in relatively wet years that was higher than in rel. dry and normal years under 3-cut system by 0. 7 and 0.6 ton DMIha, respectively. 2. Due to the lesser rainfall the nitrogen-efficiency was substantially higher with heavy dressing of nitrogen fertilizer. The absolute differences in yield between rel. dry and wet years were 0.4 and 0.7 ton DMIhalyear respectively when dressed with 90 and 120 kgN/ha/cut at 4-, 5- and 6-cut systems, whereas at 3-cut system differences around 1.3 and 1.1 ton Dhllhalyear respectively were recorded. 3. In rel. dry years the most efficient N-dressing rates per ha and year tended to be slightly higher than in rel. wet and normal years. Particularly at 5-cut system 4-7 kg/ha/cut of more nitrogen fertilization was required in order to obtain the highest overyields. 4. The N-dressing rates needed to maintain a nitrogen-efficiency of 8 to 16 kg DM/kg N tended to be stronger particularly at high cut system, and also in rel. dry years higher dressing rates were required that in rel. wet and normal years.

• Journal of Nutrition and Health
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• v.39 no.5
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• pp.460-466
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• 2006

To investigate the effects of dietary patterns on bone mineral density and its biochemical markers among Korean healthy college women for 2 years, 34 female college students were recruited through convenience sampling. Bone mineral density was measured using Dual Energy X-ray Absorptiometry (DEXA) twice at baseline and two years later. Osteocalcin and parathyroid hormone were measured in fasting serum and N-teleopeptides of type collagen (NTx) in urine. Dietary intake was assessed by 24-hour recall method 8 times with average 4-month interval. Dietary patterns with percent energy of each food group using cluster analysis were classified into two groups. The first cluster (n = 16) was characterized with high consumption of bread, snack, fast foods, beverage and considerable of rice so it was determined as 'Modified dietary pattern group'. The second cluster was characterized with high consumption of rice and kimchi so determined as 'Traditional dietary pattern group'. There were no significant difference of age, menarcheal age, body mass index but percent of body fat by pattern groups. The traditional group showed higher value of bone mineral density among lumber spine and all femur sites at baseline and 2 years later but it was not significant after adjusted for percent of body fat. Serum osteocalcin and urine NTx was higher among the traditional group at baseline than the modified group. There were similar proportions of carbohydrate:fat:protein between groups but significantly higher intake of protein, iron, vitamin A among the traditional group. In conclusion, there were two distinctive dietary patterns among Korean college women. There was difference of bone mineral density and its biochemical markers between two patterns. Further research would be necessary to explore the relationship between dietary patterns and health risks for larger-sized and various populations.

• Journal of Sport and Applied Science
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• v.7 no.2
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• pp.21-28
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• 2023

Purpose: This study was to investigate the effect of a 12-week plyometric training on body composition, physical fitness and bone mineral density in obese male adolescents. Method: Twenty adolescent boys who are obese were randomly assigned to a control group (CON, n=10) or plyometic exercise group (EXE, n=10). The EXE group was performed 3 times per week for 12 weeks. The body composition, physical fitness, and bone mineral density were measured before and after the 12 weeks intervention. Results: The results of this study were as follows: i) In EXE group, the fat mass was significantly decreased between pre and post, whereas the difference of the body weight, BMI, and LBM were not significant. ii) Among the physical fitness factors, grip strength, muscular endurance, and 2 0m shuttle running were significantly improved but flexibility did not show any significant difference. iii) The bone mineral density was significantly improved between pre and post in EXE group. Conclusion: These results suggested that plyometric training for 12 weeks may be effective in improving body composition, physical fitness, and bone mineral density in obese adolescents. Further implications were discussed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.5
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• pp.381-387
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• 2003

Winter hairy vetch (HV) can be used as green manure with conventional tillage system (CT), in which chemical N fertilizer required for cultivation of sub-sequent com could be fully saved, or as cover crop with no-tillage system (NT) in which soil could be protected from erosion, control of weed, and the reduction of N fertilizer application. This experiment was carried out to compare the enrichment of soil mineral nitrogen (SMN) at corn root zone, and the changes of com growth and N uptake according to HV amounts (winter fallow, above-ground HV removed, intact HV, and HV added from aboveground HV removed) under two tillage systems in the upland field of National Crop Experiment Station, Suwon, Korea in 1996. HV cultivation during winter decreased SMN a little at com planting. HV incorporation with CT increased SMN rapidly during early growth stage according to rapid decomposition of Hv. SMN by HV cover with NT was increased slowly and its increase was higher in the surface soil (soil layer 0-7.5cm) compared to deep soil layer 7.5-22cm. Com growth and N status at corn silking stage, com yield and N uptake at harvest were increased in proportion to aboveground HV amounts regardless of tillage system. Average hairy vetch nitrogen (HV-N) uptake efficiency by com was 10% higher with CT than with NT in which average HV-N uptake efficiency was 43 %. Corn yields were not different between two tillage systems, but corn N uptake was increased by 33 kgN/ha more with CT than with NT due to the increase of corn N concentration. The increase of SMN and com N uptake from HV cover with NT could not be disregarded though those with CT were higher than with NT

• Journal of the Mineralogical Society of Korea
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• v.25 no.4
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• pp.313-322
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• 2012

몽골 우기누르 지역 철-망간 광상과 타미르골 지역 철 광상의 광체는 먼곤체지 층 내에 렌즈상으로 협재되는 특성을 갖는다. 이러한 광상은 캠브리아 기에서 실루리아기에 이르는 화산 기원의 퇴적형 광상인 타미르골-요루골 광상구에 해당된다. 우기누르 지역의 철-망간 광체와 타미르골 지역의 철광체는 주로 규암과 편암을 모암으로 하여 먼곤체지 층 내에 렌즈상으로 협재되어 있다. 우기누르지역의 편암이 주로 세리사이트 편암인 데 비해 타미르골 지역은 주로 백운모 편암이 나타나는 차이를 갖는다. 또한 우기누르 지역의 광석은 망간이10에서 12% 함유되나 타미르골 지역의 광석은 망간이 1% 이하로 함량이 낮은 특성을 갖는다. 우기누르 철 망간 광상의 철 광물은 주로 자철석, 적철석이 우세하게 나타나고 기타 철 산화물과 황철석이 미량으로 수반되어 나타나며, 망간 광물은 주로스페사틴, 버네사이트가 우세하게 나타나고 기타망간 산화물이 수반되어 나타난다. 타미르골 지역의 철 광석은 자철석이 우세하게 나타나고 적철석이 수반되며 황철석, 철 산화물, 탄산질 철 등이 미량으로 수반되어 나타난다. 우기누르 철-망간 광상에 대한 육상 자력탐사 결과 높은 자기 이상값을보이는 영역이 지표에서 확인된 광체의 방향과 같은 약 $N30^{\circ}W$ 방향으로 나타나며 지표에서 확인된 광체 이외에 지표에 드러나지 않은 부분에서도 연장되는 것이 확인되었다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.5
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• pp.387-394
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• 2001

Blackgram (Vigna mungo) is more salt tolerant than mungbean (Vigna radiata). This study was initiated to know whether the accumulation pattern of mineral ions in different plant parts plays a significant role in the differences in salt tolerance between the two Vigna species. Different mineral ions, viz. N, Cl, Na, K, Mg and Ca in different organs of two varieties of each of blackgram- Barimash-l (susceptible one) and Barimash-2 (tolerant one), and mungbean-Barimung-3 (tolerant one) and Barimung-4(susceptible one), were analyzed after growing with 0, 50, 75 and 100 mM NaCl solutions. The two crops showed a decreased but similar pattern of total N accumulation under saline conditions. The tolerant variety of both the crops showed a less reduction in total N than the susceptible one. Leaves showed the maximum while stem the minimum N, irrespective of levels of salinity. C $l^{[-10]}$ and N $a^{+}$ accumulation increased with the increasing salinity levels. Interestingly, similar to a halophyte, the salt tolerant blackgram exhibited conspicuously higher amount of N $a^{+}$ in the shoot than the salt-susceptible mungbean. However, the tolerant varieties showed less amount of N $a^{+}$ than the susceptible one, especially in blackgram. Seeds of both Vigna spp. accumulated the minimum amount of N $a^{+}$ than other plant parts. $K^{+}$ accumulation decreased by salinity in most of the plant parts, except seeds. Blackgram showed larger reduction in K than mungbean. The $Mg^{++}$ increased in leaves, petioles and stem by salinity while decreased in the roots, podshells and seeds in both the crops. Salinity increased $Ca^{++}$ accumulation in all plant-parts except roots of both Vigna spp. Apparently, the leaves of mungbean accumulated higher concentration of $Ca^{++}$ than blackgram. Varietal differences in the accumulation pattern of $K^{+}$, $Mg^{++}$ and $Ca^{++}$ were not clear. It was concluded that blackgram, presumably, possesses a similar salt tolerance mechanism to halophyte, and the pattern of accumulation of mineral ions in blackgram and mungbean was not fully ascribed to the differences in salinity tolerance between the two Vigna species.gna species.ies.s.ies.

• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.2
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• pp.123-128
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• 1998

Legume winter cover crop hairy vetch(Vicia villosa Roth, HV) can supply mineral nitrogen for silage corn by HV cover killed. The purphose of this study was to understand changes of soil mineral N, yield and N uptake of silage corn by N level (0, 135kgFN/ha) and cover cmp(no cover crop: NCC, hairy vetch cover crop: HVC) at field of Crop Experiment Station in 1996. HV growth decreased soil mineral N concentration before seeding corn, but killed HV cover increased concentration of soil mineral N at surface soil (0~7.5cm) at six-leaf stage of corn. Total dry matter(DM) and N uptake of corn averaged over N level was more decreased in HVC than in NCC at silk stage, but N uptake of corn after silk was more increased in HVC than in NCC by N mineralized fiom HV killed, especially in OkgFNJha. N fertilization increased total DM and and N uptake of corn averaged over cover crop, especially more increased the DM and N uptake before silk stage. Early application of N fertilizer was recommendable in netillage silage corn using hairy vetch cover crop.

• Resources Recycling
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• v.26 no.3
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• pp.39-46
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• 2017

AlN powder was prepared by carbon reduction and subsequent nitridation method through lab- scale experiments. AlN powder was synthesized using the mixture of high purity $Al_2O_3$ powder and carbon black at $1,600{\sim}1,700^{\circ}C$ for 0.5~6 hours under nitrogen atmosphere (flow rate of nitrogen gas: $4.7{\times}10^{-6}{\sim}20{\times}10^{-6}m^3/sec$) with variation of charged height of the mixture powder. Experimental results showed that size of the synthesized particles grows with increasing of temperature. The reaction activation energy was calculated as 382 kJ/mol at the temperature range, and it was considered that chemical reaction is the rate determining step. Content of oxygen and nitrogen of the prpared samples were 0.71~0.96 wt% and 30.7~35.1 wt%. The results was similar with those of the commercial AlN product.