• Title/Summary/Keyword: 질소처리

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Physico·Chemical Properties of Organic and Inorganic Materials Used as Container Media (혼합배지 조제에 이용되는 유·무기 물질들의 물리·화학적 특성)

  • Choi, Jong Myung;Chung, Hae Joon;Choi, Jong Seung
    • Horticultural Science & Technology
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    • v.18 no.4
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    • pp.529-535
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    • 2000
  • Organic materials such as composted rice-hull, saw dust, and pine bark, and inorganic materials such as vermiculite, perlite, and recycled rockwool were commonly employed as container media in domestic greenhouse industry. The objective of this research was to get informations in soil physico chemical properties of those materials. Composted dry-peeling bark and wet-peeling bark had 72.1% and 69.1%, respectively, in particles larger than 1.0 mm, which were much higher than 34.7% of composted rice-hull and 33.7% of composted saw dust. Imported vermiculite had 89.9%, but domestic vermiculite had 25.7% in particles larger than 1 mm. In soil physical properties, Russian peat had the highest container capacity of 79.3%, and wet-peeling bark had the lowest container capacity of 58.2%. However, Russian peat and composted saw-dust had 4.1% in air space indicating that possible problems could occur in soil aeration when those are employed for container grown crops. Saw dust had $2.3mS{\cdot}cm^{-1}$ in electrical conductivity, while other composted organic materials had less than $0.25mS{\cdot}cm^{-1}$. Imported vermiculite had 64.0 meq/100 g in cation exchange capacity, which was 2.4 times higher than those of domestic vermiculite, 27.2 meq/100 g. Domestic vermiculite had higher Ca and Mg and less Na contents than those of imported vermiculite.

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Changes of the Oxidation/Reduction Potential of Groundwater by the Biogeochemical Activity of Indigenous Bacteria (토착미생물의 생지화학적 활동에 의한 지하수의 산화/환원전위 변화 특성)

  • Lee, Seung Yeop;Roh, Yul;Jeong, Jong Tae
    • Economic and Environmental Geology
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    • v.47 no.1
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    • pp.61-69
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    • 2014
  • As we are trying to in-situ treat (purify or immobilize) heavy metals or radionuclides in groundwater, one of the geochemical factors to be necessarily considered is the value of oxidation/reduction potential (ORP) of the groundwater. A biogeochemical impact on the characteristic ORP change of groundwater taken from the KAERI underground was observed as a function of time by adding electron-donor (lactate), electron-acceptor (sulfate), and indigenous bacteria in a laboratory condition. There was a slight increase of Eh (slow oxidation) of the pure groundwater with time under a $N_2$-filled glove-box. However, most of groundwaters that contained lactate, sulfate or bacteria showed Eh decrease (reduction) characteristics. In particular, when 'Baculatum', a local indigenous sulfate-reducing bacterium, was injected into the KAERI groundwater, it turned to become a highly-reduced one having a decreased Eh to around -500 mV. Although the sulfate-reducing bacterium thus has much greater ability to reduce groundwater than other metal-reducing bacteria, it surely necessitated some dissolved ferrous-sulfate and finally generated sulfide minerals (e.g., mackinawite), which made a prediction for subsequent reactions difficult. As a result, the ORP of groundwater was largely affected even by a slight injection of nutrient without bacteria, indicating that oxidation state, solubility and sorption characteristics of dissolved contaminants, which are affected by the ORP, could be changed and controlled through in-situ biostimulation method.

Simultaneous analysis of ethylene glycol and glycolic acid in bio-specimens by GC/MS (생체시료에서 GC/MS에 의한 에틸렌글리콜 및 대사체인 글리콜산 동시분석)

  • Lee, Joon-Bae;Park, Mee-Jung;Sung, Tae-Myung;Choi, Byung-Ha;You, Jae-Hoon;Shon, Shung-Kun;Paeng, Ki-Jung
    • Analytical Science and Technology
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    • v.23 no.6
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    • pp.544-550
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    • 2010
  • Mistaking pink colored thermal oil for grape wine, a victim drank the oil to death which was analyzed to contain 39% of ethylene glycol. Thermal oil could be used for heat transfer to prevent the malfunction due to the high pressure in the boiler operated at high temperature when using water. Main component of thermal oil is known to be mineral oil or ethylene glycol. From the blood and other tissue of the victim from autopsy, ethylene glycol and its metabolite were simultaneously analyzed by GC/MS after extraction under acidic condition with acetonitrile followed by derivatization with BSTFA. About 0.2 g of the specimens were pretreated with 50 uL of 0.5 M HCl solution to keep acidic condition, then dehydrated with anhydrous sodium sulfate followed by concentration under nitrogen stream. Ethylene glycol and glycolic acid concentration in blood was measured to be $2,755\;{\mu}g/mL$ and $174\;{\mu}g/mL$ respectively. In other specimen, the concentration of ethylene glycol and glycolic acid was $860\;{\mu}g/g\sim1,290\;{\mu}g/g$ and $93\;{\mu}g/g\sim134\;{\mu}g/g$. Especially, crystal appeared in kidney which was supposed xalate from the metabolite of ethylene glycol.

A Comparative Study on the Herbage Utilization for Mixture Types by Korean Native Goats (한국재래산양에 의한 혼파유형별 목초의 이용성 비교 연구)

  • Lee, In-Duk;Lee, Hyung-Suk
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.25 no.3
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    • pp.185-190
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    • 2005
  • The objective of this experiment was to compare the dry matter intake, nutrients digestibility and nitrogen and energy utilization of herbages from mixtures types; conventional mixtures(orchardgrass 50+ tall fescue 20+perennial ryegrass 10+Kentucky bluegrass 10+white clover $10\%$), complex mixtures (orchardgrass 40+ tall fescue 20+perennial ryegrass 10+Kentucky bluegrass 10+redtop 10+alfalfa 5+red clover $5\%$) and simple mixtures(orchardgrass 80+red clover $20\%$) by Korean native goats. This experiment was conducted by total collection method in laboratory, 2000. The voluntary DM intake per body weight was slightly higher f3r complex mixtures (30.2g) than those of other mixtures. but there was no significant difference. The digestibility of dry matter and cellular constituents were slightly higher for complex mixtures than those of other mixtures (p<0.05), but NDF and ADF digestibilities did not differ among mixtures. The retained nitrogen percent (apparently biological value) was slightly higher fer complex mixtures $(55.1\%)$ than those of other mixtures, but there was no significant difference among mixtures. Apparently retained digestible energy was slightly higher for complex mixtures $(60.2\%)$ than those of other mixtures (p<0.05). Based on the results, the nitrogen and energy utilization of herbage by Korean native goats were slightly higher for complex mixtures than those of other mixtures.

Physicochemical Properties of Dried Anchovy (Engraulis Japonica) Subjected to Microwave Drying (마이크로파 건조 방법에 따른 멸치의 건조 특성)

  • Kum, Jun-Seok;Park, Kwang-Jang;Lee, Chang-Ho;Im, Ji-Soon
    • Korean Journal of Food Science and Technology
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    • v.30 no.1
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    • pp.103-109
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    • 1998
  • For the purpose of improving quality of dried anchovy, raw anchovies after hot air drying were subjected to six different processes: 5 min microwave and 1 min holding-12 times (MW5), 10 min microwave and 1 min holding-6 times (MW10), 5 min microwave with hot air and 1 min holding-12 times (MWH5), 10 min microwave with hot air and 1 min holding-6 times (MWH10), 5 min microwave vacuum and 1 min holding-12 times (MWV5), 10 min microwave vacuum and 1 min holding-6 times (MWV10) at 100 Watt and 2450MHz. There were no significant effects of different processes on water content, pH, color, acid value and volatile basic nitrogen. The sum of fatty acids on commercial anchovy occupied 38.34% of saturates 22.91% of monoenes and 22.91% of polyenes and dried anchovies subjected to microwave processes had similar compositions. Dominant fatty acids were palmitic acid and docosahexaenoic acid in each process. Among the free amino acids, alanine, arginine, lysine and leucine were dominant in all processes. Dried anchovies showed little significant differences in texture in all processes. Sensory evaluation data showed that the quality of dried anchovy subjected to microwave process was acceptable and microwave vacuum process was the most desirable one.

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Conditions of Water Activity of Raw Material and Adding Levels of Papain and Glucose for Processing Fermented Squid with Low Salt Concentrations (저염 오징어젓갈의 제조를 위한 원료어육의 수분활성도와 papain과 glucose의 첨가조건)

  • Jo, Jin-Ho;Oh, Se-Wook;Kim, Young-Myoung;Chung, Dong-Hyo
    • Korean Journal of Food Science and Technology
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    • v.30 no.1
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    • pp.62-68
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    • 1998
  • To develop methods to produce low salt fermented squid with rich flavor and acceptable shelf life, the optimum processing conditions such as water activity of raw material, amounts of NaCl, papain and gucose were investigated. Water activity of squid meat was adjusted to 0.94 (raw meat), 0.90 and 0.88 by cold air blast and each was salted with 3, 5, or 7% NaCl followed by fermenting at $10^{\circ}C$ for 6 weeks. Amino nitrogen was increased rapidly with high water activity and low NaCl concentration. As a result of organoleptic evaluation it was concluded that optimum conditions were to adjust water activity of raw material to 0.90 and to salt with 5% NaCl. When squid meat adjusting water activity to 0.90 was treated with 0.05, 0.1 and 0.5% papain and fermented at $10^{\circ}C$ for 6 weeks, SDS-PAGE pattern showed rapid breakdown of myofibrilar protein with increasing amounts of papain but the treatment with 0.1% enzyme was best organoleptically. pH values of squid meat added with 1 and 2% glucose were maintained lower than control (glucose 0%) but there were no significant differences between the two glucose treatments. Therefore, it was thought that adding of glucose might be extended shelf life of fermented squid with low salt concentration.

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Advanced Wastewater Treatment of Low Concentration Ammonia Using the Immobilized Nitrifier Consortium (고정화 질화세균을 이용한 저농도 암모니아 폐수의 고도처리)

  • Lee, Jung-Hoon;Kim, Byong-Jin;Kim, Yong-Ha;Yi, Gyeong-Beom;Lim, Jun-Heok;Cheon, Jae-Kee;Suh, Kuen-Hack
    • Korean Chemical Engineering Research
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    • v.40 no.6
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    • pp.763-768
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    • 2002
  • This study was performed in the airlift bioreactor using the nitrifier consortium entrapped in polyvinyl alcohol(PVA) for removing low concentration total ammonia nitrogen(TAN). At the superficial air velocity of 0.83 cm/sec, TAN removal rate and removal efficiency was $316.6{\pm}7.2g/m^3{\cdot}day$ and $92.8{\pm}2.2%$ respectively. Removal rate was continuously increased with decreasing hydraulic residence time(HRT) from 0.5 hr to 0.05 hr, whereas removal efficiency decreased with decreasing HRT. The optimum temperature for nitrification was $30^{\circ}C$ at which removal efficiency was $95.5{\pm}1.5%$. Nitrification was effectively performed at low temperature, $10^{\circ}C$. In the pH range from 7 to 9 in the bioreactor, removal rate and removal efficiency was $310{\pm}10g/m^3{\cdot}day$ and $94{\pm}3%$ respectively.

Temperature-Dependent Effects of Pollutants on Biological Denitrification Process for Treating Cokes Wastewater (코크스폐수의 생물학적 탈질공정에 대한 독성물질의 온도에 따른 영향)

  • Kim, Young Mo;Park, Donghee;Ahn, Chi Kyu;Lee, Min Woo;Park, Jong Moon
    • Korean Chemical Engineering Research
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    • v.46 no.6
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    • pp.1124-1129
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    • 2008
  • Cokes wastewater is one of the most toxic industrial effluents since it contains high concentrations of pollutants, such as phenol, ammonia, thiocyanate and cyanides. Although biological pre-denitrification process has been used to treat this wastewater in Korea, unexpected failure in nitrogen removal occasionally occurs during summer season. In this study, therefore, we examined inhibitory effects of phenol, ammonia, thiocyanate, ferric cyanide and free cyanide on biological denitrification according to temperature variation ($20{\sim}38^{\circ}C$). Batch experiments showed that denitrification rate was faster in summer ($38^{\circ}C$) than other seasons, and removal rates of pollutants increased with increasing temperature. Phenol, ammonia, thiocyanate and ferric cyanide did not inhibit denitrification even at its high concentration (200 mg/L). However free cyanide above 0.5 mg/L seriously inhibited the bilolgical denitrification reaction. Inhibitory effect of these pollutants was reduced with increasing temperature.

Mechanistic Studies for Electrochemical Oxidation of ${\iota}$-Sparteine (${\iota}$-Sparteine의 전기화학적 산화반응에 대한 메카니즘의 연구)

  • Jin-Hyo Park;Chang-Soo Jin;Sung-Nak Choi;Yoon-Bo Shim
    • Journal of the Korean Chemical Society
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    • v.37 no.8
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    • pp.711-716
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    • 1993
  • The mechanism for electrochemical oxidation of natural alkaloid, ${\iota}$-sparteine (SP) was studied in acetonitrile solvent. The cyclic voltammogram of SP shows two irreversible anodic peaks at +0.75 V and +1.45 V vs. Ag/AgCl (0.1M AgNO$_2$ in acetonitrile) electrode. Coulometry reveals that the number of electrons involved in each oxidation peaks is in the range of 1.2∼1.3 respectively. Neutral imine radical was produced by fast deprotonation of SP radical cation formed by oxidation of one nitrogen atom in SP. Two pathways are possible for the reaction of the neutral radical: Due to the disproportionation of the radical, SP and enamine were mainly produced. Also, the 1,2-dehydrosparteinium cation was formed as minor product through the second one electron transfer oxidation of this radical. The (+)-lupanine was produced by treatment of sparteinium cation with potassium hydroxide. We have isolated and confirmed the electrolysis products using IR, GC-MS, UV-Vis, and thin-layer spectroelectrochemical method.

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Anti-inflammatory and Anti-allergic Effects of Phlorofucofuroeckol A and Dieckol Isolated from Ecklonia cava (감태에서 분리된 플로로탄닌의 염증 및 알러지 억제 효과)

  • Lee, Seung-Su;Bang, Myun-Ho;Jeon, Hyeong-Ju;Hwang, Taekyoo;Yang, Seun-Ah
    • Journal of Life Science
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    • v.28 no.10
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    • pp.1170-1178
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    • 2018
  • The anti-inflammatory effect of brown alga Ecklonia cava is well known, and several phlorotannins have also been reported. In this study, major active components for anti-allergy and anti-inflammation were identified by NMR and MS analysis, and the levels of effectiveness were compared. Six major phlorotannins-phloroglucinol, eckol, eckstolonol, triphlorethol-A, phlorofucofuroeckol A, and dieckol-were isolated from the ethyl acetate fraction of E. cava. In order to analyze the major active substances in E. cava, antioxidant, anti-inflammatory, and anti-allergic effects were evaluated for the six separate substances. Antioxidant capacities of each phlorotannin were evaluated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radicals, where phlorofucofuroeckol A and triphlorethol-A had the highest radical scavenging capacity in respective radical scavenging assays. Phlorofucofuroeckol A exhibited the highest inhibition of nitric oxide production in LPS-stimulated RAW 264.7 cells among phlorotannins tested. Dieckol inhibited the release of ${\beta}-hexosaminidase$, a marker for the release of histamine in mast cells, in a dose-dependent manner in antigen-stimulated RBL-2H3 mast cells. Additionally, no cytotoxicities were observed at 1 and $2{\mu}g/ml$ in both phlorofucofuroeckol A and dieckol. These results suggest that phlorofucofuroeckol A and dieckol may play a key role in allergic inflammatory reactions.