• Journal of the Korean Society of Clothing and Textiles
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• v.14 no.3 s.35
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• pp.216-221
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• 1990

This study was performed for the development of antimicrobial finished nonwoven fabrics with water repellency. And it was aimed to examine the changes of moisture related properties and air permeability of the finished fabrics. Viscose rayon nonwoven fabrics were treated with organic silicon quaternary ammonium salt having carbon numbers of 16, which was synthesized for this study Antimicrobial activity was evaluated by shake flask method and the reactivity of antimicrobial agent was measured by degree of luminescence from inductively coupled plasma. Water repellency of treated specimen was evaluated by dynamic water absorption measurement and air permeability was measured by Frazier method. The results obtained from this study were as follows: 1. Excellent antimicrobial activity was obtained for the high concentration of treatment and the durability of finishing after laundering was better as the treatment concentration was higher 2. Silicon contents taken up by specimen increased with increased treatment concentration. 3. Dynamic water absortion of treated specimen decreased compared to that of untreated. And, it was lowered as the treatment of concentration increased and as the silicon content increased. 4. Moistuie regain and uptake with lapse of time of treated specimen increased compared to those of untreated. But, air permeability of treated specimen decreased.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.6
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• pp.694-703
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• 2012

To understand the characteristics of sedimentary and benthic environments in habitats of naturally-occurring intertidal benthic macroalgae, various geochemical parameters of sediment (grain size, ignition loss [IL], chemical oxygen demand [COD], and acid volatile sulfur [AVS]) and pore water (temperature, salinity, pH, and nutrients) were measured in the southern intertidal zone of Hampyeong Bay at two month intervals from April to October 2009. Ecological characteristics including the distribution and biomass of benthic macroalgae were also investigated. Benthic macroalgae were distributed below 4 to 5 m depth from mean sea level near the lower portion of the intertidal zone where air exposure time is relatively short. The distribution area and biomass of benthic macroalgae gradually decreased during the study period. The surface sediments in the benthic algal region were mainly composed of finer sediments, such as slightly gravelly mud and mud. The temperature, salinity, pH, and nutrient concentrations (except dissolved inorganic nitrogen) in pore water did not differ in regions with and without benthic macroalgae, whereas the mean grain size and the concentrations of IL, COD, and AVS in sediments were much higher in regions harboring benthic macroalgae. The correlation between mean grain size and IL in sediments displayed two distinct gradients and the slope was much steeper in regions harboring benthic macroalgae, indicating that the content of organic matter in benthic algal region is not solely dependent on mean grain size. Our results indicate that the benthic macroalgae in the southern intertidal zone of Hampyeong Bay play an important role in the accumulation of organic matter in sediment.

• Environmental Engineering Research
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• v.20 no.2
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• pp.149-154
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• 2015

In recent years, immobilization agents were introduced into organic contaminated soil remediation and more and more materials were screened and used as the immobilizing carrier. However, effect of the decomposition of the immobilizing carrier on the bioremediation was rarely concerned. Therefore, the decomposition experiment of immobilizing carrier -corncob was carried out in the lab with the efficient degradation fungi - Mucor mucedo (MU) existing, and polycyclic aromatic hydrocarbons (PAHs) residues E4/E6 of the dissolved organic matter and microbial diversity during the decomposition process were studied. The results showed that: a) during the decomposition, the degradation of pyrene (Pyr) was mainly in the first 28 d in which the content of extractable Pyr decreased rapidly and the highest decrease was in the treatment with only MU added. b) Anslysis of E4/E6 changes showed that rich microorganisms could promote aromatization and condensation of humus. c) From the diversity index analysis it can also be seen that there is no significant difference in effects of PAHs on the uniformity of microorganisms. These results will not only be useful to have a better understanding of the bioavailability of contaminants adsorbed to biodegradable carriers in PAHs contaminated soil remediation, but also be helpful to perfect the principle of immobilized microbial technique.

• Environmental Engineering Research
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• v.25 no.4
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• pp.536-544
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• 2020

To address organic dye wastewater, economic and effective adsorbents are required. Here, magnetic biochar from alkali-activated rice straw (AMBC) was successfully synthesized using one-step magnetization and carbonization method. The alkaline activation caused the large specific surface area, high pore volume and abundant oxygen-containing groups of the AMBC, and the magnetization gave the AMBC a certain degree of electropositivity and fast equilibrium characteristics. These characteristics collectively contributed to a relative high adsorption capacity of 53.66 mg g^-1 for this adsorbent towards rhodamine B (RhB). In brief, RhB can spontaneously adsorb onto the heterogeneous surface of the AMBC and reach the equilibrium in 60 min. Although the initial pH, ionic strength and other substances of the solution affected the adsorption performance of the AMBC, it could be easily regenerated and reused with considerable adsorption content. Based on the results, H-bonds, π-π stacking and electrostatic interactions were speculated as the primary mechanisms for RhB adsorption onto the AMBC, which was also demonstrated by the FTIR analysis. With the advantageous features of low cost, easy separation, considerable adsorption capacity and favorable stability and reusability, the AMBC would be a potential adsorbent for removing organic dyes from wastewater.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.4
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• pp.100-106
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• 2005

Sugar beet stillages were used as a substrate for the production of single cell protein by the thermotolerant yeasts Candida rugosa, Kluyveromyces marxianus and C. utilis. The biomass production increased in accordance with the increase of pH-value, but protein content decreased. C. rugosa showed the highest crude protein production as 3.68g/l and C. utilis 2.9g/l, Kl. marxianus 2.30g/l, respectively. The rate of COD reduction in stillage versus crude protein production of C. rugosa showed the highest value as 0.35~0.39g/l as a good strain for single cell protein production using sugar beet stillages.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.4
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• pp.79-88
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• 2005

The wastes generated in farming or fishing villages are mostly those of high moisture content or those once used for farming or fishing work, which require a complex process even for disposing of them alone, and moreover they have been recognized to cause a secondary side effects. The study thus is intended to conduct the basic character analysis and incineration test so as to develop the thermal decomposition furnace which will be optimal in disposing of the wastes generated from urban area that mostly have a high thermal energy or require a complex treatment process. And the subject included in the study, in addition, is to design and develop the furnace aimed at reducing the harmful ingredient as well as recycling the heat generated in the course of incineration.

• Journal of the Korea Organic Resources Recycling Association
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• v.3 no.1
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• pp.61-71
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• 1995

This study is concerned with the assessment of the possibility of alum sludge composting, as well as changes of some chemical properties during composting. Alum sludge was mixed in different proportions, which are 0%, 25%, 35% and 45%, respectively, with a sewage sludge and sawdust mixture. The final mixtures to be composted are placed on static piles constructed with a perforated aeration pipe on the ground, and composted for more than 50 days. During the composting of some alum sludge treatments, there was not notable difference in changes of pH, C/N ratio, and content of several minerals among the alum sludge treatments, while changes of pile temperatures and CEC were significant and these remarkable differences in related to the pile temperatures and CEC seem suitable for the evaluation of alum sludge maturity. Also, the results suggested that the proper mixing ratio of alum sludge for composting was 25% level.

• Journal of the Korea Organic Resources Recycling Association
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• v.21 no.2
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• pp.71-78
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• 2013

This study examined the feasibility of phosphorus removal from dewatering centrate/filtrate in wastewater treatment by struvite formation. Since dewatering centrate/filtrate obtained after anaerobic digestion contains a high content of ammonia, magesium addition and pH adjustment could remove phosphorous. The optimum magnesium dose, reaction time, settling time, and pH value was found at 2 mol Mg/mol $PO_4^{3-}$, 10 min, 120 min, and 8.5, respectively. A bench-scale continuous operation at the optimum condition showed 80% of total phosphorus removal and 82% of phosphate removal in dewatering centrate. The elemental composition and crystal structure of the chemical precipitate was similar to the reported values of struvite.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.6
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• pp.749-758
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• 2004

Nitrous oxide ($N_2$O) has been known as an important trace gas due to the greenhouse gas and the major source of stratospheric oxide of nitrogen (NO). Soil is the major source of $N_2$O in nature. The physicochemical characteristics of soils affect the emission of $N_2$O from soil. These physicochemical parameters are soil moisture, soil temperature, and soil N content. Since these parameters are correlated to the flux of $N_2$O from soil individually and compositely, there still remain many unknowns in the mechanism to produce $N_2$O in soil and the roles of such physicochemical parameters which affect the soil $N_2$O emission. Soil $N_2$O fluxes were measured at different levels in water filled pore space (WFPS), soil temperature and soil N contents from the same amounts of soils which were sampled from agriculturally managed upland field in a depth of ～30 cm at Kunsan. The soil $N_2$O flux measurements were conducted in a laboratory with a closed flux chamber system. The optimum soil moisture and soil temperature were observed at 60% of WFPS and ～13$^{\circ}C$. The soil $N_2$O flux increased as soil N contents increases during the whole experimental hours (up to 48 hours). However, average $N_2$O flux decreased after ～30 hours when organic carbon was mixed with nitrogen in the sample soils. It is suggested that organic carbon could be important for the emission of $N_2$O, and that the ratio of N to C needs to be identified in the process of $N_2$O soil emission.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.4
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• pp.64-73
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• 1999

This study was conducted to find out the effects of hydroseeding material and seed mixture on the revegetation of rock cut-slopes by PEC4 (Polymer-Ecology-Control) Hydroseeding Measures. PEC4 hydroseeding material was applied to four cut-slopes using hydroseeding measures from April to August, 1999, and the field survey was carried out by monthly. PEC4 material consisted of bark compost and organic soil amendments. This material has high content of organic matter and high level of water holding capacity. PEC4 hydroseeding material shows low level of soil hardness, so it gives to good condition for seed germinating and plant growing in early stage. PEC4 material attached at rock cut-slopes by two types of adhesive agent was not eroded by rainfall. The plant coverage and number of plant species were affected by mixing ratio of seeds and seeding timing. From the viewpoint of plant establishment, the optimal hydroseeding timing of mixed seeds for plant growth seems to be in May. Most of the plant seeds were germinated well and they covered rock cut-slopes so quickly and effectively. Plant importance value of Silene armeria and Platycodon grandiflorum. were higher than any other seeded-native species in the competition between native species and exotic species, so they have enough possibility to be used for slope revegetation works. Thus it leads to conclusion that the revegetation method used in this experiment was a very effective method for plant establishment on rock cut-slopes.