• Journal of Korean Society of Environmental Engineers
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• v.39 no.12
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• pp.664-671
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• 2017

Non-point source pollution is the emission source that unspecifically releases pollutants to water system from unspecific places such as cities, agricultural lands, mountains, and construction sites and its discharge path is not easily identified. Also, it is difficult to design and manage the reduction facilities for the emission quantity is primarily affected from weather conditions like rainfall. Since 2006, the significance of non-point source pollution reduction has been grown in Republic of Korea and this reinforces needs for the installation of reduction facilities. However, because the standards for the installation details and reduction efficiency are not clarified by law, people are preferring technologies that do not require particular maintenance and high expenses. The purpose of this study is to examine and maintain the efficiency of non-point source pollutants reduction facility which uses expended polypropylene as a media. The higher the depth of the media, the less range of variations in the reduction efficiency was observed and the final efficiency was also increased. When the media depth was 60 cm, the average reduction efficiency was 94% and 90% where linear velocities were 10 m/hr and 20 m/hr respectively. The results from 180 minutes operation in 10 m/hr and 20 m/hr of linear velocities were slightly different in head loss changes which were caused by media depth variations. The backwash experiments which were conducted in triplicate showed the reduction efficiency decreased as the time went on because of the media clogging. However, it was found that after the backwashing the reduction efficiency was increased as effective as the efficiency of the initial filtration.

• Parasites, Hosts and Diseases
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• v.23 no.2
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• pp.253-259
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• 1985

In order to correlate the number of eggs In female Enterobius vermicularis with their body length and to re-evaluate the number of eggs liberated by gravid females, a total of 203 worms were examined. Those females were removed from naturally infected orphans with mebendazole (100mg) and had been fixed in 10% formalin(Cho et al., 1981). The decent ones which were selected under dissecting microscope were unbroken, neatly fixed females without contaminated eggs on their surface. The worms were measured by their body length, softened in 0.1N NaOH solution overnight, and teased by dissecting needles. And their number of shelled eggs was measured in a counting chamber made as described by Denham et at. (1971). The results were summarized as follows: 1. The observed females, 4.10~9.90mm long, began to have shelled eggs in uterus when body length was 5.50mm or longer. 2. The percentage of females with eggs in uterus was as follows by range of body length: 25% in 5.50~5.99mm long, 53.3% in 6.00~6.49mm long, 86.7% in 6.50~6.99mm long, 95.2% in 7.00~7.49mm long and 100% in 7.50mm or longer. 3. The mean and standard deviation of egg number were as follows by the length of females: $19{\pm}50$ in 5.50~5.99mm long, $734{\pm}1,597$ in 6.00~6.49mm long, $1,473{pm}1,606$ in 6.50~6.99mm long, $1,530{\pm}2,055$ in 7.00~7.49mm long, $2,567{\pm}2,046$ in 7.50~7.99mm long, $5,598{\pm}2,470$ in 8.00~8.49mm long, $9,318{\pm}2,651$ in 8.50~8.99mm long, $10,678{\pm}2,892$ in 9.00~9.49mm long and $13,323{\pm}1,778$ in 9.50~9.90mm long. 4. The numbers of uterine eggs showed greater individual variation when the female lengths were in range of 5.5~8.0mm. When the female length was longer than 9.0mm, the egg numbers were over 10,000 in majority, and showed lesser individual variations. Above results su99ested that the e99 Production in female 5. vermicularis began in 28~32 days after infection and that in early stapes, the egg Production varied by individual worms, but in gravid females longer than 9. Qmm at last deposited 10,000 to 16,000 eggs in their uterus with the least individual variations.

• Asian Journal of Turfgrass Science
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• v.22 no.2
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• pp.171-178
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• 2008

We have found the clusters of tiny spiny puffball-like mushrooms growing gregariously in fairy ring (arcs) rimmed by a zone of darker green grass in the golf courses. Macroscopic as well as microscopic characters were examined for the morphology of fruiting body. Exoperidium is thin and densely spiny with minute fibrillae at early stage. The connivent spines were soft and quite persistent. In age, the fibrillae scrumble away with a powdery coating, which leaves white endoperidium becoming pale brown. It's interior was white and fleshy at first, but turns into an olive-colored dust as the gleba, the spore-producing tissue, develops to maturity and loaded with olive-brown spore mass. Then, distinct apical pore developed on the endoperidium. Rudimentary subgleba(sterile base) was narrow, chambered, delineated from the gleba by a membrane in young material. These characters suggested this fungus is a Vascellum, a member of the family Lycoperdaceae. The shapes of the spores were globose, echinulate, $3{\sim}3.5{\mu}m$ in diameter, thick-walled, and olive brown. Capillitial threads were $8-9{\mu}m$ wide, mostly colorless in KOH solution and thin-walled, which designated as "paracapillitium". This is an another character that distinguishes this mushroom from Lycoperdon spp. The spines developed on exoperidium were characteristically connivent; their apices joined together in a point, leaving a space below, which gives the appearance of vault to each group of usually 5 to 6 fibrillae. Based on the above characters, this fungus is identified as Vascellum curtisii (Berkeley). The characters distinguishable this from Lycoperdon pulcherrimum, and Vascellum pretense are discussed in detail. Control trial was also attempted. Strong vertical raking(SVR) followed by applying 500x detergent solution (Spark, Aekyung Co. Seoul) resulted in excellent control over any other treatments. In this plot, fruiting body was not developed throughout the end of mushroom growing season.

• Food Science and Preservation
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• v.21 no.1
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• pp.121-128
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• 2014

This study was conducted in order to investigate the change of isoflavone composition (glycoside and bio-active aglycone), and to evaluate the quality characteristics of Cheonggukjang, which was prepared by different bacillus strains. After the 48-hour fermentation, the contents of daidzein, genistein, and glycitein in the Bacillus subtilis HJ18-3 have significantly increased up to approximately $89.06{\pm}3.59$, $10.36{\pm}0.28$, and $101.37{\pm}3.67ug/g$, respectively. The contents of daidzein, genistein, and glycitein in the Bacillus subtilis KACC 15935 were $38.88{\pm}5.39$, $12.58{\pm}2.14$, and $80.13{\pm}0.71ug/g$, respectively. The original content of daidzein was 3.96 ug/g, while genistein and glycitein were not measured. However, the contents of daidzen and genistein in HJ18-3 and in KACC 15935 were decreased. The ${\alpha}$-Amylase and cellulase activities of Chungkookjang in HJ18-3 were higher than in the KACC 15935. The contents of Chungkookjang in HJ18-3 were $29.70{\pm}11.66$ and $4861.3{\pm}388.07unit/g$, respectively. The amino type nitrogen contents and ammonia type nitrogen contents of Chungkookjang in KACC 15935 were higher than in the HJ18-3. These results suggested that it could be used to increase the bioactivity via fermentation with the Bacillus subtilis possessing a ${\beta}$-glucosidase activity with a view towards the development of functional foods.

• Korean Journal of Weed Science
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• v.11 no.2
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• pp.111-116
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• 1991

This studies were conducted to get the basic information on the growth habits of Scirpus planiculmis F. Schmidt for control in poldered paddy field. The distribution of corm was about 16% in 0-5cm, 66% in 5-8 cm. 18% in 8-10cm depth of underground. The mean depth of total corm distribution was about 6.51cm. Number of rhizomes and dormant buds per corm were one to four, respectively. Number of rhizomes. dormant buds and total buds(rhizome+dormant bud) were 2.34, 2.85 and 5.20, respectively. The phyllotaxy of S. planiculmis was 1/3 and bracteal leaf were showed from first to 4th leaves. The period of propagation to 100 plants from emergence was 58.52 and 48 days for corm seeded on March 25th, b4ay 7th and June 6th respectively. Days to emergence of S. planiculmis from emergence of previous plant was gradually shorted. as order of propagation from corm seeded progressed. The other side, length of rhizome, plant height and diameter of culm was increased. The plant height of S. planiculmis was higher than rice plant from early stage in rice direct seeding culture, and from 30 dats after transplanting in rice transplanting culture. Speed of propagation was faster in rice direct seeding culture than in rice trasplanting culture.

• Journal of the Mineralogical Society of Korea
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• v.21 no.4
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• pp.341-347
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• 2008

The feasibility of commercializing the hydrothermal synthesis of Na-A type zeolite from siliceous mudstone has been conducted using a 50-liter bench-scale autoclave and the application of the zeolite as an environmental remediation agent. Siliceous mudstone, which is widely distributed around the Pohang area, was adopted as a precursor. The siliceous mudstone is favorable for the synthesis of zeolite because it contains 70.7% $SiO_2$ and 10.0% $Al_2O_3$, which are major ingredient of zeolite formation. The synthesis of zeolite was carried out under the following conditions that had been obtained from the previous laboratory-scale tests: 10hr reaction time, $80^{\circ}C$ reaction temperature, $Na_2O/SiO_2$ ratio = 0.6, $SiO_2/Al_2O_3$ ratio = 2.0 and $H_2O/Na_2O$ ratio= 98.6. The crystallinity and morphology of the zeolite formed were similar to those obtained from the laboratory-scale tests. The recovery and cation exchange ion capacity were 95% and 215 cmol/kg, respectively, which are slightly higher than those obtained in laboratory scale tests. To examine the feasibility of the zeolite as an environmental remediation agent, experiments for heavy metal adsorption to zeolite were conducted. Its removal efficiencies of heavy metals in simulated waste solutions decreased in the following sequences: Pb > Cd > Cu = Zn > Mn. In a solution of 1500 mg/L total impurity metals, the removal efficiencies for these impurity metals were near completion (> 99%) except for Mn whose efficiency was 98%. Therefore, the synthetic Na-A type zeolite was proven to be a strong absorbent effective for removing heavy metals.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.3
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• pp.55-69
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• 2001

To study the possibility of agricultural utilization of seafood processing wastewater sludges, the changes of temperature and humus, the form of organic matter and nitrogen and the germination ratio of plant during the composting were investigated. The results were summarized as follows. Temperature was rapidly increased at early stage of composting, reached to $67{\sim}76^{\circ}C$ in highest temperature at 3~5 days, and then decreased gradually fallen to $40{\sim}50^{\circ}C$ at 19 days after composting, at the point was upset firstly. The third upset was conducted at 60days after composting, and then the temperature was little changed. The contents of total organic matters in the compost for composting were down 4.5~8.0%. Ether extractable materials, resins and hemicellulose contents of the organic matters for composting were decreased with 35~77%, 32~69% and 19~30%, respectively. And cellulose, lignins and unknown materials contents in the organic matters for composting were increased a little, but water soluble polysaccharides of organic matters were little changed. Total nitrogen, amino sugar and amino acid nitrogen contents in the compost for composting were decreased with 20~42%, 11~49% and 23~65%, respectively. The contents of humic acid in the compost for composting were little changed, but contents of fulvic acid in the compost for composting were decreased gradually. Germination ratio of radish, chinese cabbage and cucumber were over 90%, when the compost produced at 30 days after composting was tested on plant germination.

• The Korean Journal of Quaternary Research
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• v.19 no.1
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• pp.1-17
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• 2005

This study aims to study the distribution and formation age of Quaternary deposits in the downstream of Yeongsan Estuarine River, encompassing Muan, Illo and Donggang counties. For this purpose the authors examine several borehole data, and step trench survey for excellent profiles was studied in connection with grain size population and magnetic susceptibility. As a result, it is interpreted that the coastal plain of the Yeongsan River was formed by sea level rise after Last Glacial Maximum(LGM). The fore edge/escarpment of coastal terraces distributed 7-10 m asl is assumed to be formed during the last glacial period, while the coastal terraces distributed above 7-10m asl formed during MIS 5a. In addition, the fore edge/escarpment of coastal terraces distributed above 15 m asl is presumed to be have been formed during the stadial of last interglacial period, while the formation age of coastal terraces distributed above 15m(asl) is assumed to be MIS 5e. This formation age can be estimated by the coastal terrace ages of the southeastern coast of Korean Peninsula. The characteristics of Quaternary deposits linked to paleolithic culture will eventually lead to the reconstruction of ecosystem environment of paleolithic peoples.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.11
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• pp.599-606
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• 2017

The effects of microbubble-oxygen physicochemical method for the removal of organic pollutants, nitrogen, and phosphorus contained in animal manure were investigated using a laboratory scale single reactor. The characteristics of used livestock manure were $36,894{\pm}5,024mg\;TCOD/L$, $22,031{\pm}2,018mg\;SCOD/L$, $4,150{\pm}35mg\;NH_4-N/L$, and $659{\pm}113mg\;PO_4-P/L$. It was confirmed that the amount of organic pollutants, nitrogen, and phosphorus removal was increased by the use of oxygen rather than air as the gas supplied with the microbubble, and by input of larger oxygen amount. When the oxygen was fed with 600 mL flow rate per minute, TCOD and phosphorus removal were 2.5 times and 5.6 times higher than those of air supplied. As the microbubble-oxygen reaction time was longer, the removal rate of nutrients increased gradually. The removal rates of ammonium and phosphorus reach to $41.03{\pm}0.20%$ and $65.49{\pm}1.39%$, respectively, after 24 hours. When the coagulation treatment method was applied to increase phosphorus removal rate from the effluent of microbubble-oxygen treatment, the phosphorus was removed up to 92.7%. However, the removal rate of organic pollutants (TCOD) was as small as $28.7{\pm}0.2%$ within the first 6 hours, and then the negligible removal of TCOD was recorded. This study suggests that microbubble-oxygen can be applied not only livestock manure but also aeration tank of various wastewater treatment plant, which can reduce the load on the associated unit process and produce stable high-quality effluent.

• Journal of Korean Society of Forest Science
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• v.78 no.3
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• pp.280-286
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• 1989

The present study was to examine the effects of light, temperature, and water stress on the photosynthesis and respiration rates and its seasonal changes in 3-Year-old Fraxinus rhynchophylla and Fraxinus mandshurica seedlings raised in pot in nursery. The results obtained are as follows: 1. The estimated light compensation points at which net photosynthesis approached zero were 35 and $28{\mu}Em^{-2}\;s^{-1}$ for F. rhyrachophylla and F. mandsdzurica leaves, respectively, The light saturation points occurred at $700{\mu}Em^{-2}\;s^{-1}$ in these species. 2. The maximum rates of net photosynthesis of leaves occurred at about $25^{\circ}C$ in F. rhynchophylla and at $20^{\circ}C$ in F. mandshurica. 3. The decrease in net photosynthetic rates of leaves began at -13 bars in F. rhynchophylla and -10 bars in F. mandshurica, and then its rates approached approximately zero at -23 bars in F. mandshurica and -29 bars in F. rhynchophylla. 4. The dark respiration rates of leaves were similar from $10^{\circ}C$ to $40^{\circ}C$ between these species, Also these increased from -10 bars to -28 bars, and then decreased remarkably in these species. 5. The net photosynthetic rates of leaves of F. mandshurica were higher than those of F. rhynchoplaylla until June, and after that lower than F. rhynchophylla. The dark respiration rates of leaves of F. rhynchophylla were higher than those of F. mandshurica from June to August, and After that similar between these species. 6. The respiration rates of stem and root were highest in April during the growing season. These values of F. rhynchophylla were slightly higher than those of F. mandshurica throughout the growing season.