• Korean Journal of Environment and Ecology
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• v.25 no.4
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• pp.490-497
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• 2011

This study was carried out to identify environmental factor to influence fruiting of Vicia chosenensis populations distributed in Hongcheon-gun region, Korea. The populations was dominated by Quercus mongolica in the tree layer, and Lindera obtusiloba and Lespedeza maximowiczii in the shrub layer. Syneilesis palmata(21%) was abundant around reproductive state points and vegetative state points, and Artemisia stolonifera(13~18%) and Spodiopogon sibiricus(10~11%) show second high frequency in the both points. It was found that the soil moisture content in the Vicia chosenensis population was 20.4~21.9%; 8.6~14.9% for organic matter; 0.3~0.5% for the total N;12.7~16.9 ppm for available phosphorus; 22.5~28.5 $cmol_ckg^{-1}$ for CEC; 5.3~5.5 for soil pH, respectively. The microhabitat of individuals was restricted to areas high in understory light. Especially, reproductive individuals were more likely to be located than vegetative individuals in canopy gaps. Therefore, our results suggest that a proper forest management maintaining canopy gaps is needed for keeping natural Vicia chosenensis population.

• Journal of Plant Biology
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• v.12 no.1
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• pp.22-30
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• 1969

To investigate the effects of internal radiation of various intensityon the test crop(flax), seeds of four levels of activity($15.5{\times}10-4 $\mu$c/grain, 9.0{\times}10-2$\mu$c/grain, 2.2{\times}100$\mu$c/grain and 3.8{\times}10-1$\mu$c/grain)$ which had been obtained by immersing them into various concentrations of P-32 original solution (total activity: 90 mc, To: 3/21) for 24 hours at room temperature, were germinated, transplanted later into pots, and the rate of germination and the successive growth were observed, and the inorganic conents of the plant top were analyzed. The results are as follows: 1. At the early stage of germination, the plants manifested themselves both inhibitory and promotive effects at higher and lower activity levels respectively, compared those of the control. These difference of growth on account of different levels of activity appeared, however, to be gradually narrowed in the course of time after germination, except at the highest activity. 2. Two weeks after transplanting, the plants of the lowest activity showed more vigorous growth than those of control. The plants belonging to the other activity levels on the other hand, tended to be less growing, the higher the activity. However, this growth gap between treatments seemed to be progressively closed one month after transplanting. 3. Most of the leaves and stems of the plants belonging to the highest activity level ($3.8{\times}101$\mu$c/grain$) were withered during the early stage of growth, and this damage did not recover. 4. Practically no difference of growth was observed among treatments(excluding that of highest activity) one and half months after transplanting. 5. The fluorescence tended to be mroe delayed than the control, as the activity decreased. 6. There was a tendency that the number of pods harvested were larger in the plants treated with P-32 than that of the control. 7. The proportion of fiber in the plants at harvest appeared to be larger at lower activity and smaller at higher P-32 concentration than that of control. 8. As for the inorganic contents of the plant top harvested the floowing tendency was observed: (1) Nitrogen content was highest at the highest activity level at which the poorest growth ensued. (2) There was no clear difference of phosphorus content among treatments. (3) The contents of potassium and magnesium were higher than control at the medium levels of activity. (4) Calcium content of all treated blocks was found to be more than that of control.

• Korean Journal of Agricultural Science
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• v.37 no.2
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• pp.191-197
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• 2010

The objective of this research was to determine the influence of the physical and chemical properties of root substrates used during the production of 'Maehyang' strawberry propaguleson the growth of the mother plants and the rate of daughter plant formation. Plants were cultured in plastic bags containing six different formulations of root substrates composed of: a) 50% coir dust and 50% perlite (5:5 by volume, A), b) 60% coir dust and 40% perlite (6:4, B), c) 70% coir dust and 30% perlite (7:3, C), d) 70% coir dust and 30% coconut chip (7:3 D), e) 60% coir dust and 40% coconut chip (60:40, E), or f) 50% sphagnum peat and 50% vermiculite (50:50, F). All media formulations contained a moderate level of base fertilizers. Physical and chemical properties of each formulation were determined before plant establishment and after 120 days of stock plant culture and runner production. Total porosity (TP) and container capacity (CC) of all substrate formulations were higher than 85% and 55%, respectively, allowing a suitable range of air and water holding characteristics. Formulation F provided the highest TP and CC values among the all substrate modifications evaluated. Substrate formulations A, B, C and F had higher electrical conductivity (EC) and $NO_3{^-}$-N concentrations than formulations D and E, when determined before and after plant culture. Formulations A, B, C, and F, having higher EC readings, also performed better as root substrates thanthe formulations D and E in increasing fresh and dry weights of the runners as well as the production of daughter plants per plant. The 'Maehyang' strawberry plants grown in the formulation F had the highest tissue N content, followed by those grown in substrate B, A, C, or D for 120 days after transplanting. Formulation F also facilitated accumulation of higher tissue phosphorus (P) and copper (Cu) contents compared to other treatments. Results of this experiment suggest that the chemical properties, rather than physical properties, of root substrates had a major influence on the growth of mother plants and the occurrence of healthy daughter plants during the bag-culture phase of propagation.

• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.309-315
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• 2003

Nutritional composition, contents of phenolic compounds, and antioxidative activities of small black soybean were investigated. Proximate composition of the soybean was crude fat, crude protein, carbohydrate, and crude ash at 15.9, 34.7, 38.5, and 3.7%, respectively. Potassium was the predominant mineral, followed by phosphorus, calcium, and magnesium. Glucose and galactose were the major sugars. Twelve different kinds of fatty acids were identified in whole soybean, dehulled soybean, and soybean hull. The 75% methanol and ethyl acetate extract fractions from the soybean hull contained total phenolic compounds at 4.64 and 13.53 g/100 g, respectively. The methanol extract of soybean hull showed strongest antioxidative activity among samples tested. Ethyl acetate fraction of the soybean hull exhibited DPPH radical scavenging activity at level similar to those of ${\alpha}-tocopherol$ and BHT. Phenolic compounds were the major biological components in the soybean hull. These results suggest that small black soybean can be used as a new material for functional food.

• Journal of Korean Society of Forest Science
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• v.106 no.1
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• pp.10-18
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• 2017

This study was carried out to suitable plantation site from comparison and analysis of regional early growth characteristics of planted Larix kaempferi trees in harvested L. kaempferi plantations. Two-year-old bare-root seedlings of L. kaempferi were planted with the density of $3000\;seedlings\;ha^{-1}$ at four sites (Yeongju, Gimcheon, Chuncheon, and Inje). All sites were established with three plots ($400m^2$ per plot) in 2010. We analyzed soil physical and chemical properties in October 2010 and 2013. We measured root collar diameter (RCD) and height of trees in October from 2010 to 2014, and then calculated H/D ratio and stem volume. Soil pH was significantly increased and available P was significantly decreased 3 years after planting. Annual mean RCD, height, and stem volume of 5-to 7-year-old in the Chuncheon site were significantly higher than those in the other sites, however them in the Yeongju site were the lowest. It is related to the fact that total nitrogen, available phosphorus, and organic matter concentrations in the Yeongju site were relatively lower than those in the other sites. As a results of this study, we could confirm the correlation between soil properties of L. kaempferi plantations and growth of L. kaempferi trees. We could suggest values of soil properties for reforestation of L. kaempferi.

• Applied Biological Chemistry
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• v.47 no.2
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• pp.208-215
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• 2004

As a part of a study on the effective use of cultured oyster, oyster powder-added soybean pastes were prepared and its characteristics were examined. As the concentration of oyster powder added to commercial soybean paste was increased, the moisture level decreased, the crude and amino nitrogen content increased with no change in the salinity and titratable acidities. Also, the color of the soybean paste changed to a darker color as the concentration of oyster powder added to commercial soybean paste increased. Judging from the results of the above experiment and sensory evaluation, the optimal additive concentration of oyster powder to commercial soybean paste was revealed as 9%. The total amino acid content of oyster powder-added soybean paste was 2% higher than that of commercial soybean paste. The ratio of calcium and phosphorus of oyster powder-added soybean paste was about 1:2-2:1, an improvement in calcium absorption as compared to commercial soybean paste. Functional fatty acids, such as 20:5n-3 and 22:6n-3, were not detected in commercial soybean paste but detected in oyster powder-added soybean paste. The major free amino acids in oyster powder-added soybean paste were glutamic acid and aspartic acids. According to the above results, the nutritional, functional and taste properties of commercial soybean paste were improved while reducing preparation time of the housewife.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.6
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• pp.601-607
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• 2002

The present study was designed to examine how sea tangle intake contributes to the content of bone calcium and breaking force of femur with growing female rats. Weaned rats were fed on experimental diets consisting in four levels of sea tangle powder; $0\%$ (control), $0.5\%$, $1.0\%$ and $1.5\%$ for 4 and 8 weeks. Body weight gain and feed intake were not significantly affected by added amount of sea tangle. Bone breaking strength, ash content and calcium levels of the femur of rats fed on diets with sea tangle were higher than those of control groups (p<0.05). But moisture content weight and length of femur did not show any significant difference among groups. TP, ALB, TC, TG, AIP, osteocalcin, GOT and GPT levels in serum did not show any significant difference through the total feeding period but calcium and phosphorus contents of serum increased with increase in feeding period, significantly in $0.05\%$ level by added amounts of sea tangle. Calcium levels in feces increased significantly (P<0.05), but ash levels were not changed significantly by added amount of sea tangle. We could expect from this results that the ingestion of sea tangle (Kjellemaniella crassifolia) could be helpfull to increase bone calcium content and calcium absorption as well as to intensify the femur stength and to increase the calcium content of rats.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.2
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• pp.114-120
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• 2000

The aim of this study was to investigate the effects of slow-released nitrogen fertilizer(SRNF) on the growth and yield of rice. SRNF produced from wasted paper was applied to a clay loam paddy field comparing to urea fertilized field and only P-and K-fertilized field. Some agronomic components like as growth development and yield component were observed and physico-chemical properties of the soils were analyzed. Plant height and tiller numbers per hill showed higher in rice plant treated with SRNF than in one treated with urea at the early grow stage whereas they appeared to be all much the same at the end of growth stage. While the chlorophyll content in SRNF-treated rice shoot was higher than in urea-treated one, the photosynthetic activity in urea-treated rice shoot was slightly higher than in SRNF-treated rice. In harvested grain, the nitrogen content was higher than in SRNF treated rice than in urea treated rice, but in straws the content was less. At the harvesting stage, nitrogen uptake in grains was about 4% higher in SRNF-treated rice than in urea treated rice whereas in straws rather 20% lower. The N efficiency in SRNF treated rice was lower than in urea treated rice. In the soils treated with SRNF, pH, organic matter and phosphorus were higher than in the soils treated with urea. Total N content in SRNF treated soil was lower after experiment than in urea treated soil.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.289-289
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• 2013

While there are plenty of studies on synthesizing semiconducting germanium nanowires (Ge NWs) by vapor-liquid-solid (VLS) process, it is difficult to inject dopants into them with uniform dopants distribution due to vapor-solid (VS) deposition. In particular, as precursors and dopants such as germane ($GeH_4$), phosphine ($PH_3$) or diborane ($B_2H_6$) incorporate through sidewall of nanowire, it is hard to obtain the structural and electrical uniformity of Ge NWs. Moreover, the drastic tapered structure of Ge NWs is observed when it is synthesized at high temperature over $400^{\circ}C$ because of excessive VS deposition. In 2006, Emanuel Tutuc et al. demonstrated Ge NW pn junction using p-type shell as depleted layer. However, it could not be prevented from undesirable VS deposition and it still kept the tapered structures of Ge NWs as a result. Herein, we adopt $C_2H_2$ gas in order to passivate Ge NWs with carbon sheath, which makes the entire Ge NWs uniform at even higher temperature over $450^{\circ}C$. We can also synthesize non-tapered and uniformly doped Ge NWs, restricting incorporation of excess germanium on the surface. The Ge NWs with carbon sheath are grown via VLS process on a $Si/SiO_2$ substrate coated 2 nm Au film. Thin Au film is thermally evaporated on a $Si/SiO_2$ substrate. The NW is grown flowing $GeH_4$, HCl, $C_2H_2$ and PH3 for n-type, $B_2H_6$ for p-type at a total pressure of 15 Torr and temperatures of $480{\sim}500^{\circ}C$. Scanning electron microscopy (SEM) reveals clear surface of the Ge NWs synthesized at $500^{\circ}C$. Raman spectroscopy peaked at about ~300 $cm^{-1}$ indicates it is comprised of single crystalline germanium in the core of Ge NWs and it is proved to be covered by thin amorphous carbon by two peaks of 1330 $cm^{-1}$ (D-band) and 1590 $cm^{-1}$ (G-band). Furthermore, the electrical performances of Ge NWs doped with boron and phosphorus are measured by field effect transistor (FET) and they shows typical curves of p-type and n-type FET. It is expected to have general potentials for development of logic devices and solar cells using p-type and n-type Ge NWs with carbon sheath.

• Korean Journal of Microbiology
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• v.34 no.4
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• pp.188-193
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• 1998

The authors examined the variations of environmental factors, the distributions of cyanobacteria, heterotrophic bacteria, and microorganisms that inhibit the growth of Anabaena cylindrica according to development and extinction of cyanobacterial bloom at a site in Daechung Dam reservoir. And certified the relationship between each other. Water temperature variated in a typical pattern. pH and concentrations of dissolved oxygen and chlorophylla was high in bloom period, and lowered with the decline of bloom. Phosphorus played as a growth-limiting factor at this study site. Total nitrogen concentration increased during blooming period, which indicated that nitrogen has been fixed by aquatic organisms such as cyanobacteria. Cyanobacteria distributed from June 17, and such cyanobacterial species as Anabaena spp., Aphanizomenon spp., Microcystis spp., Oscillatoria spp. and Phormidium spp. was detected during study period. Anabaena spp. distributed relatively highly distributed from July 23 to September 22, and disappeared completely at September 29. Heterotrophic bacterial and cyanobacterial populations varied inverse-proportionally. There was a relevancy between the variations of Anabaena spp., heterotrophic bacteria, and microorganisms that inhibit the growth of Anabaena cylindrica. Microorganisms that inhibit the growth of Anabaena cylindrica distributed from early growth phase of Anabaena spp. population to immediately after the extinction of Anabaena spp. With the population of Anabaena cylindrica growth-inhibiting microorganisms decreasing, increases of heterotrophic bacterial population followed it. Thease results indicate that microorganisms have a part in the extinction of cyanobacterial bloom, especially at its destroying period.