• 아시안잔디학회지
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• 제6권1호
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• pp.1-10
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• 1992

This experiment was carried out to investigate the effect of mixing ratio of soil amending materials such as peat. perlite, active carbon, and zeolite on the growth and quality of creeping bentgrass (Agrostis pa1ustris var. Penncross). The results of this experiment were surnrnarized as follows; 1.Nitrogen content of clippings was increased by the treatment of peat and active carbon. hut the other phosphorus, potassium, calcium and magnesium content were increased in addition of,5% to 10% of peat, and 2.5% to 5% of active carbon. 10% of perlite. and 4% of zeolite 2.Fast growth and good quality of bentgrass were showed at the addition of 10% peat. l0% perlite.2.5~% active carbon, and 4% zeolite But over treatment of peat and active carbon induced inhi-bition of root growth and occurrence of disease.

• Bulletin of the Korean Chemical Society
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• 제7권1호
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• pp.23-25
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• 1986

Reaction of ${\alpha}-cyano-{\beta}-phenylacrylic$ acid derivatives (Ⅰ) with thioglycolic acid in the molar ratio of 1:2 in saturated sodium bicarbonate solution yielded 3-(4'-oxo-2'-thiazolin-2'-yl)-2-phenyl-4-oxotetrahydrothiophene derivatives (V). Thioglycolic acid was found to be added not only to carbon-carbon double bond but also to carbon-nitrogen triple bond and those adducts were cyclized to V.

• 한국물환경학회지
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• 제22권1호
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• pp.134-139
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• 2006

Partial nitirification and denitrification process has been reported to be technically feasible and economically favorable, especially for wastewater treatment with high ammonium concentration or low Carbon/Nitrogen ratio. This research was performed to survey nitrite accumulation by nitritation in treating ADEPT effluent of piggery wastewater, which contains highly concentrated ammonia. To estimate the possibility of nitrite accumulation, DO concentration and SRT were investigated as key operational parameters. This result proved that nitritation to nitrite was steadily obtained under short sludge retention time. Oxygen limitation was proved to be just a subsidiary parameter. Energy efficiency of nitritation-denitritation process was higher than complete nitrification-denitrification because external carbon requirement for denitritation could be saved. Though the influent contained significant nonbiodegradable organic substrate, total nitrogen removal efficiency was more than 51% in nitritation-denitritation system.

• KSBB Journal
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• 제7권2호
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• pp.102-106
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• 1992

본 연구에서는 C. bombiocola에서 생성되는 미생물 계면활성제인 Sophorolipid의 생산관여인자 중, 질소원의 종류에 따른 영향과 C/N비율에 따른 생성량의 변화를 관찰하였다. 유기질소원이 비교적 놓은 생성량을 보였으며 그 중 pepton의 경우가 80g/L에 해당하는 높은 생성량을 보였다. C/N의 비율의 변화에 의한 Sophorolipid의 생성량의 변화 양상이 질소원의 종류에 따라 각기 다르게 나타났다. 또한 탄소원의 50%을 배양 이틀후 공급하는 방법으로 Sophorolipid가 약 30% 증가됨을 알 수 있다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.227-230
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• 2000

Batch cultivations of Anaerobiospirillum succiniciproducens have been systematically studied for the economical production of succinic acid from wood hydrolysate with corn steep liquor(CSL) as a nitrogen source. CSL was found to be an alternative complex nitrogen source for A. succiniciproducens when glucose and wood hydrolysate were used as carbon sources. Compared with polypeptone and/or yeast extract, CSL had similar effects on fermentation performance such as succinic acid yield and a ratio of succinic acid to acetic acid in the fermentation of wood hydrolysate as well as glucose. This means that succinic acid can be produced more economically from wood hydrolysate and CSL than relatively expensive carbon and nitrogen sources. Besides its low cost, the alternative medium served as a green technology for succinic acid production because it gives a net-zero effect on global warming.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 추계학술대회 초록집
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• pp.175.1-175.1
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• 2011

A rotating activated bacillus contactor (RABC) process with a series of aerobic reactors was tested in pilot scale to treat digested liquid from an anaerobic digester treating swine wastewater and sewage sludge. The influent (digested liquid) for the RABC process showed C/N ratios less than 2 as a typical feature of effluent from anaerobic digesters. The pilot process, which consists of three 3 RABC reactors, four aerobic tanks and a sedimentation tank, was operated for 210 days with a hydraulic retention time of 20 days without pH and temperature control. Since the Bacillus-enriched aerobic reactors shows high efficiencies of nitrogen removal at low DO levels less than 1.0 mg/L, they were operated at reduced aeration intensities. With relatively low concentrations of organics in comparison with nitrogen concentrations, the RABC process tested in this study showed stable and high nitrogen and organics removal efficiencies over 80%. The nitrogen removal process tested in this study was proven to be an effective and operation-cost saving (lower aeration) method to remove nitrogen without adding external carbon sources to meet the optimum C/N ratio.

• Carbon letters
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• 제10권4호
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• pp.293-299
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• 2009

Potassium hydroxide activated carbons were prepared from Egyptian petroleum cokes with different KOH/coke ratios and at different activation temperatures and times. The textural properties were determined by adsorption of nitrogen at $-196^{\circ}C$. The adsorption of iodine and methylene blue was also investigated at $30^{\circ}C$. The surface area and the non-micropore volume increased whereas the micropore volume decreased with the increase of the ratio KOH/coke. Also the surface area and porosity increased with the rise of activation temperature from 500 to $800^{\circ}C$. Textural parameter considerably increased with the increase of activation time from 1 to 3 h. Further increasing of activation time from 3 to 4 h was associated with a less pronounced increase in textural parameters. The adsorption of iodine shows the same trend of surface area and porosity change exhibited by nitrogen adsorption, with KOH/coke ratio and temperature of activation. Adsorption of methylene blue follows pseudo-first-order kinetics and its equilibrium adsorption follows Langmuir and D-R models.

• Journal of Advanced Marine Engineering and Technology
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• 제18권2호
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• pp.91-96
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• 1994

Intake gases other than air, which is composed of oxygen, nitrogen, carbon dioxide, and argon, are used to study their effects on the performance of the diesel engine experimentally. The engine is operated at constant speed and fixed fuel injection timing, and cylinder pressure and heat release rate are measured at various intake gas compositions. The results show that increase of oxygen concentration improves the performance of the engine generally. The adverse effect is observed when the oxygen concentration is increased over the critical oxygen concentration of this test, mainly because of the over-shortened ignition delay. Increase of carbon dioxide concentration degardes the performance of the engine, mainly due to the lower specific heat ratio of carbon dioxide. Adding argon gas to the intake gas improves the overall performance. Finally, it is found that two most influencing factors affecting the performance of the diesel engine in this study are ignition delay and speific heat ratio of the intake gas.

• 약학회지
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• 제53권5호
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• pp.293-297
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• 2009

The abuse of methamphetamine (MA) is one of the most serious drug abuses in Asia. And, the prevention of precursor production for abuse drug is one of the most effective drug control system. Isotope ratio analysis at natural abundance levels have been used to establish the environmental source or the geographic origin of various biological and nonbiological materials. Ephedrine, the precursor of MA, is produced by one of three methods; extraction from Ephedra plants, full chemical synthesis or via a semi-synthetic process involving the fermentation of sugar, followed by amination. We investigated the origin of ephedrine and pseudoephedrine based on the carbon and nitrogen values for nineteen pharmaceutical powder materials (PPMs) obtained from pharmaceutical company in Korea by stable isotope ratio mass spectrometry coupled to an elemental analyser (EA-IRMS). The carbon delta values for the ephedrine and pseudoephedrine were -24.21~-22.72 (mean=-23.72) $^{\cir}/_{\circ\circ}$ and -23.79~-22.71 (mean=-23.48) $^{\cir}/_{\circ\circ}$. The nitrogen delta values were 3.51~5.55 (4.43) $^{\cir}/_{\circ\circ}$ and 2.24~8.22 (5.42) $^{\cir}/_{\circ\circ}$. These results indicate that PPMs are semi-synthetic products. Therefore the origins of ephedrine(natural, semi-synthetic or synthetic) could be discriminated by using carbon and nitrogen stable isotope ratios. we are sure tat this stable isotope ratio analysis can discriminate the origins of precursors of methamphetamine.

• 상하수도학회지
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• 제13권4호
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• pp.35-44
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• 1999

In this study, it was attempted to remove nitrate and carbon in a single-stage reactor using acetate as substrate. Hybrid type upflow sludge baffled filter reactor was adopted using anaerobic sludge. Sludge bed in the bottom of reactor was intended to remove carbon and nitrate by denitrification and methanogenesis. And floating media in the upper part of reactor were intended to remove remaining carbon which was not removed due to the inhibition of nitrogen oxide on methane producing bacteria. The reactor removed over 96% of COD and most of nitrate with volumetric loading rate of $4.0kgCOD/m^3{\cdot}day$, hydraulic retention time of 24hr, 4,000mgCOD/L, and $266mgNO_3-N/L$. Nitrate in anaerobic sludge was converted to nitrogen gas(denitrification) or ammonia (ammonification) according to pH of influent, COD removal efficiency was easily affected by the change of volumetric loading rates and nitrate concentration. And when influent pH was about 4.7, most nitrate changed to ammonia while when influent pH was about 6.8~7.0, most nitrate denitrified independent of $COD/NO_3-N$ ratio. Most granules were gray and a few were black. In gray-colored granule, black inner side was covered with gray substance and SEM illustrated Methanoccoci type microorganisms which were compact spherical shape. Anaerobic filter removed residual COD effectively which was left in sludge bed due to the inhibition of nitrogen oxide.