• Journal of Mushroom
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• v.7 no.1
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• pp.9-21
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• 2009

This study was executed in an attempt to investigate a artificial requisites of fruitbody occurrence. Environmental requirements on habitat for fruitbody occurrence of collected cultures resulted in leading to $13-16^{\circ}C$ and 75% relative humidity, and requiring silt loam of soil texture which had more nutritional substances than a dry field. Optimal temperature was $25^{\circ}C$, medium PDB, and pH 5.0 in cultural conditions. Mannose required of 5% in ASI 59002, 59003, 59004, but 3% in ASI 59001 was selected as optimum carbon source. The substrates stimulating sclerotium formation were cotton waste, or cotton waste + oak sawdust (mixture ratio of 8:2), which had 20% additive of wheat barn respectively. Sclerotium was formed well in the substrate adjusted chemical properties by applying 2% of calcium sulfate. Sclerotium formation was the most effective in the treatment of peat moss + oak sawdust (mixture ratio of 5:5) + 30% of wheat barn.

• Journal of Life Science
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• v.21 no.10
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• pp.1473-1480
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• 2011

Perchlorate ($ClO_4^-$) is a contaminant found in surface water and soil/ground water. Microbial removal of perchlorate is the method of choice since microorganisms can reduce perchlorate into harmless end-products. Such microorganisms require an electron donor to reduce perchlorate. Conventional perchlorate-removal techniques employ heterotrophic perchlorate-reducing bacteria that use organic compounds as electron donors to reduce perchlorate. Since continuous removal of perchlorate requires a continuous supply of organic compounds, heterotrophic perchlorate removal is an expensive process. Feasibility of autotrophic perchlorate-removal using elemental sulfur granules and activated sludge was examined in this study. Granular sulfur is relatively inexpensive and activated sludge is easily available from wastewater treatment plants. Batch tests showed that activated sludge microorganisms could successfully degrade perchlorate in the presence of granular sulfur as an electron donor. Perchlorate biodegradation was confirmed by molar yield of $Cl^-$ as the perchlorate was degraded. Scanning electron microscope revealed that rod-shaped microorganisms on the surface of sulfur particles were used for the autotrophic perchlorate-removal, suggesting that sulfur particles could serve as supporting media for the formation of biofilm as well. DGGE analyses revealed that microbial profile of the inoculum (activated sludge) was different from that of the biofilm sample obtained from enrichment culture that used sulfur particles for $ClO_4^-$-degradation.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.5
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• pp.538-555
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• 2012

The purpose of this study was to understand $PM_{2.5}$ chemical characteristics on the Suwon/Yongin area and further to quantitatively estimate $PM_{2.5}$ source contributions. The $PM_{2.5}$ sampling was carried out by a high-volume air sampler at the Kyung Hee University-Global Campus from November, 2010 to October, 2011. The 40 chemical species were then analyzed by using ICP-AES(Ag, Ba, Cr, Cu, Fe, Mn, Ni, Pb, Si, Ti, V and Zn), IC ($Na^+$, $K^+$, $NH_4{^+}$, $Mg^{2+}$, $Ca^{2+}$, $NO_3{^-}$, ${SO_4}^{2-}$ and $Cl^-$), DRI/OGC (OC1, OC2, OC3, OC4, OP, EC1, EC2 and EC3) and GC-FID (acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene, benzo[b]fluoranthene, benzo[a] pyrene, indeno[1,2,3-cd] pyrene, benzo[g,h,i]perylene and dibenzo[a,h,]anthracene). When applying PMF model after performing proper data treatment, a total of 10 sources was identified and their contributions were quantitatively estimated. The average contribution to $PM_{2.5}$ emitted from each source was determined as follows; 26.3% from secondary aerosol source, 15.5% from soil and road dust emission, 15.3% from vehicle emission, 15.3% from illegal biomass burning, 12.2% from incineration, 7.2% from oil combustion source, 4.9% from industrial related source, and finally 3.2% from coal combustion source. In this study we used the ratios of PAHs concentration as markers to double check whether the sources were reasonably classified or not. Finally we provided basic information on the major $PM_{2.5}$ sources in order to improve the air quality in the study area.

• Korean journal of applied entomology
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• v.48 no.3
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• pp.327-333
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• 2009

Biological Characteristic of Obolodiplosis robiniae and insecticidal activity of some insecticides against larvae of O. robiniae were investigated. Egg was in oval shape, and its color was light orange and became red when close to hatch. Length of the major axis and the minor axis of egg was 0.4 mm and 0.1 mm, respectively. Larval color was milky and size was 2.6 mm. Pupa was deep brown and its size was about 3.2 mm. Wing and abdomen of adult was black and reddish, respectively. Size of female adult was about 3.3 mm, and larger than male adult. Number of eggs in the ovary was $192.3{\pm}50.7$. First emergence was from late April to late May, and second from late May to late June. Third emergence was from late June to late July. Newly emerged adult escaped from soil, and second and third emerged adult escaped directly from gall of Robinia pseudoacacia leaf. Egg parasitoid was identified as Platygaster robiniae and parasite rate was 51.6%. Among test insecticides, imidacloprid 10% WP and thiacoprid 10% FL showed very strong insecticidal activity against larvae of O. robiniae at 48h later after treatment.

• Korean journal of applied entomology
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• v.48 no.3
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• pp.319-325
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• 2009

Woolly apple aphid, Eriosoma lanigerum, overwintered as adult or nymph stage on rootstocks, and crown- and root sucker in the soil. In an un sprayed apple orchard, the number of E. lanigerum colony started to increase from mid-April, showed the 1st peak between late June and early July, thereafter decreased followed by the 2nd peak in late July, and then again peaked in late September as the size in the 1st peak. In this orchard, the number of E. lanigerum colonies per tree did not exceed 3.5 colonies during the peak occurrence period, and was maintained around 2 colonies throughout seasons. In all seasons, parasitism of Aphelinus mali on E. lanigerum was much lower on root colonies than on aerial colonies that located on shoots and tree trunks above the ground. The parasitism of E. lanigerum was high in most orchards examined, showing parasitism of > 70% in maximum in most cases. In the laboratory bioassay for the mortality effects of several insecticides on E. lanigerum, fenitrothion, dichlorphos, machine oil, methidathion, thiacloprid, and imidacloprid showed 97.8, 96.8, 95.4, 91.5, 26.7, and 7.8% morality, respectively. Also, the adult emergence rates from A. mali mummies were 51.2, 72.6, 14.2, 3.5, 72.2, and 85.4% in the treatment of the above insecticides, respectively. Insecticides belong to neonicotinoid, which are newly developed to control aphids, showed low mortality against E. lanigerum. Fenitrothion and dichlorphos were effective on E. lanigerum control and had a low toxic to A. mali. Consequently, the insecticides should be useful in integrated pest management system for E. lanigerum in apple orchards.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.1
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• pp.100-114
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• 2005

Organic waste, which is defined as wastes derived from various biological organisms that contain more than 40% of organic materials, is generated about 100 million tons per year in Korea. These organic wastes are now controlled by several governmental entities, under different rules and regulations, leading to the improper management and inefficient treatment. Therefore, integrated management system is primarily needed for the efficient recycling of organic waste. In this study, six kinds of organic wastes, which are food waste, sludges(sewage, waste water, night soil), animal excreta, animals and plants residues, and three kinds of recycling by-products(compost, feed, anaerobic digestion by-products) made of organic wastes, were analyzed for their physical and chemical characteristics. On the basis of this result, a possibility for the efficient recycling of organic waste was investigated.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.2
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• pp.221-227
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• 1995

White clover (Trifolium repens L) gives rise to either weak persistence or overdominance in the pastures. To get information on grazing method to surmount the problem, the experiment was done to measure the effect of infrequent, frequent and their alternations on harvest yield and morphological characteristics of the clover. Individual plants of Regal, Louisiana S-l, Grasslands Huia, and Aberystwyth S184 were grown in 22cm plastic pot containing a 2： 1： 1 soil： sand： Peat moss mixture for 27 days after transplanting 50-day seedlings raised on 3cm pots, and then their all fully expanded leaves are trimmed. Defoliation treatments were forced every 1 (CC, frequent), 4 week(RR,infrequent) or their alternations(CR, RC) after 8 weeks from the trimming. To analyze the treatment effects, plants were sampled on 4, 8, 12, and 16 weeks after the trimming. Harvest yield of infrequent defoliation (RR) was higher than that of frequent defoliation (CC). Leaf area and no. of leaves per plant, petiole length and stolon length per plant, moreover, showed the similar result to the yield but stolon length and leaf area per g were reverse. The alternation of infre-quent and then frequent defoliation (RC) had greater yield than that of their reverse (CR) although both alternations showed intermediate ones compared to CC and RR. Morphological characteristics, furthermore, related to the clover leaf were immediately changed by alternations of defoliation inter-val(RC and CR) while those done to the stolon were lasted longer thereafter(RC and CR). Harvest yields in RC and CR were positively correlated to leaf area and no. of leaves or stolon length per plant but negatively done to leaf area and stolon length per g. It is concluded that weak persistence or overdominance of white clover in pasture can be controlled by alternation of infrequent and then frequent defoliation or reverse.

• Korean journal of applied entomology
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• v.40 no.1
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• pp.83-88
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• 2001

Residual effect of imidacloprid on brown planthopper (BPH) and residues on rice plant were investigated in pot and field tests. Residual effect (showing 100% mortality) of imidacloprid of granule formulation on the BPH lasted for 40 days at a recommended dose (0.3 kg a.i./ha) and for 30 and 20 days at a half and a quarter of the recommended dose, respectively. In case of liquid formulation of imidacloprid, the residual effect lasted for 40 days at both recommended dose (0.032 kg a.i.1ha) and a half of it, and lasted for 30 days at a quarter of it. The next generation formation of BPH was throughly depressed by the imidacloprid application at the former generation. This result supports the residual effect of imidacloprid on BPH. Seed dressing (3 ghg) showed insecticidal activity (96.7% mortality) for 55 days after treatment. When granule formulation of imidacloprid was applied to soil at a recommended dose , imidacloprid residue in leaves of rice plant increased up to 0.46 ppd for 6 days and then decreased to 0.09 ppm on 40 days after application. Residue of imidacloprid in leaves of rice plant increased up to about 0.23 ppm and about 0.2 ppm for 6 days when applied at a half and a quarter of the recommended dose, respectively and after that they decreased.

• Journal of Korean Society of Forest Science
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• v.80 no.2
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• pp.237-245
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• 1991

Artificial acid rain (pH 3.0, 4.0 and 5.0) was treated on thd seeds of 5 coniferous species to examine its effects on germination and seedling growth. Artificial acid rain was prepared by diluting sulfuric acid with ground water and ground water(pH 6.5) was used as control. Artificial acid rain was sprayed to seeded pots three times per week. About 5mm of artificial acid rain was treated each time from early April to early October, 1990. Germination, seedling establishment and seedling growth were measured and compared among the treatments. The results were summarized as follows ; 1. Germination, seedling establishment rate of Larix leptolepis and Picea koraiensis were highest on the pH 5.0 plot whereeas those of Abies holophylla and Cryptomeria japonica were highest on the control plot, and those of Abies koreana showed the highest value on the pH 3.0 plot. 2. The differences in seedling height growth of Larix leptolepis was signif- icant at 1% level among the treatment levels of acid rain, whereas those of other species were not significant, Height of Larix leptolepis, Abies koreana and Picea koraiensis were highest on the pH 4.0 plot, and that of Abies holuphylla and Cryptomeria japonica were highest on the pH 5.0 plot. 3. Seedling dry weight of Larix leptolepis and Abies holophylla differed significantly at 1% level among the treatments, but those of other species did not differ. Highest seedling dry weight of Larix leptolepis and Abies koreana were observed on the pH 4.0 plot, and that of Abies holophylla and Cryptomeria japonica did on the pH 3.0 plot, and that of Picea koraiensis did on the control plot. 4. With decrease of pH value of artificial acid rain, the number of injured needle and injured individual tended to be increased, obviously. 5. The differences of soil acidity were highly significant among the treatments for all species.

• Journal of Mushroom
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• v.15 no.2
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• pp.69-72
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• 2017

Diversification to develop oak pruned neck utilization technology reduction of operation cost of cheonma(Gastrodia elata) farmers is the purpose of this research, but the results of the experiment are as follows. The soil chemistry of the plantation was very weak in 2015 when the pH was 5.7, weakly acidic and EC was 0.41 (ds/m), but the faux spring area was very sunny, but at the end of May, early June, late July And so on were at a maximum temperature of $25^{\circ}C$ or more, and underground temperature fell below freezing in late January 2016. In the content of the survey of the harvested volume, treatment with a diameter of 6 to 10 cm appeared in 1,366 g total weight and in treated plots with a diameter of 20 cm or more, appeared in 1,542 g, confirming that the number and weight of the interspaces from the small neck is higher than the practice.