• 한국초지조사료학회지
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• 제20권4호
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• pp.265-274
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• 2000

To investigate the effects of anion replacement on NO3- concentration in Italian ryegrass. Plants weregrown hydroponically to the full vegetative stage. NO3 supply(control) was replaced with SO1- (Tl), C1-(T2) and water (T3) to during 14 days. The determination of inorganic nutrient uptake and quantification ofprincipal metabolites (nitrate. protein and sugar) followed. Relatively high uptake of ~ a a'n d Ca" for controlplants, K+ and POJ- for T2 plants, and C 1 for TI plants was observed, respectively. Proteins in shoot andstubble were relatively higher in control and TI plants, which coupled N source. In root proteins largelydecreased (especially in T3 plants) during experimental period. Sugars in shoot of all four treatments tendedto decrease during the first 7 days and recovered afterward. Sugars in stubble also markedly decreased duringthe first 7 days, while those in root was much less varied during experimental period. After 14 days oftreatment, nitrate concentration in shoot of control plants was 13mgIg FW. Comparing to control: nitrate inshoot reduced by 27%, 46% and 50% in TI, T2 and T3 plants, respectively. Dry weight was slightlyincreased or not significantly changed in control, T1 and T2 plants, while a significant decrease(31.3% ofcontrol) occurred in T3 plants.(Key words : Italian ryegrass, Anion replacement, Ion uptake, Protein, Sugar, Nitrate)ptake, Protein, Sugar, Nitrate)

• 한국환경농학회지
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• 제20권5호
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• pp.352-357
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• 2001

Cadmium (Cd) has been identified as a potential contaminant in agricultural and environmental soils. Ionic condition in the soils is an important factor to influence Cd availability. In this study, the effect of sulfate or nitrate application on Cd sorption in acidic and calcareous soils was investigated. The Cd, sulfate $(SO_4)$, and nitrate $(NO_3)$ sources were solutions of $CdCl_2$, $K_2SO_4$, and $KNO_3$, respectively. The soil-solution system pH was affected by the application of sulfate or nitrate in both acidic and calcareous soil system, but there was not clear pH difference between pre- and simultaneous applications of sulfate or nitrate (PAS/PAN or SAS/SAN). Solution ionic strength (I) values were similar between the acid and calcareous soil systems after applying the Cd even though it was significantly different in the untreated control soils. However after applying the sulfate or nitrate, the I values increased and were always higher with SAS/SAN treatments. Solution Cd concentration also increased with the application of sulfate or nitrate. However, the Cd concentration in soil solution controlled by Cd sorption in the systems was different between PAS/PAN and SAS/SAN treatments only in the calcareous soil system, but not in the acidic soil system. The difference in Cd concentration between SAS/SAN and PAS/PAN in the calcareous systems may be caused by system pH, ionic strength, complexation, and predominately, competition of the $Cd^{2-}$ with the index $K^+$ ion. Potassium ion-Cd competition in the acidic soil system may be minimized because of the abundance of hydrogen ions.

• Journal of Microbiology and Biotechnology
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• 제15권2호
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• pp.412-420
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• 2005

In order to investigate factors affecting the denitrification in the F-STEP PROCESS using a loess ball as support media and Pseudomonas DWC 17-8, calcining temperature, loess ball size, pH, nitrate concentration, working temperature, and inhibitor were studied in batch mode using synthetic sludge. A 5- 10 mm of loess ball (960$^{circ}$ of calcining temperature) was the most suitable for denitrification. When the initial pH was increased from 3.0 to 7.0, the removal efficiency of nitrate was increased. Specifically, at initial pH of 7.0, the maximum removal efficiency of nitrate was 5.0 mg/min. When the initial concentration of nitrate was increased from 100 to 400 mg/l, the removal efficiency of nitrate was proportional to the concentration of nitrate. The maximum removal efficiency of nitrate was 5.72 mg/min at 400 mg/l of initial concentration. When the operating temperature was increased from 10 to 30$^{circ}$, the removal efficiency of nitrate was increased from 0.76 to 6.15 mg/min, and at above 40$^{circ}$ of operating temperature, it was decreased from 4.0 to 2.0 mg/min. Among the various inhibitors, higher than 10$^{-1}$ M of sodium azide abolished this reaction completely. When the KCN concentration was above 10$^{-1}$ M, the reaction was inhibited completely. In the case of 2,4-dinitrophenol and sodium sulphide, it was inhibited at above 10$^{-2}$ M completely. For testing the various flow orders of the F-STEP PROCESS for effective denitrification using practical wastewater, continuous experiments under the optimum conditions were carried out for 60 days. Among the various processes, the PROCESS A gave the highest efficiencies of denitrification, nitrification, and total nitrogen (TN) removal with 86.5, 89.5, and $90\%$, respectively. For scale-up in the PROCESS A, real farm wastewater was used and pilot tests carried out for 90 days. The denitrification efficiency was $97.5\%$, which was increased by $12.7\%$. The efficiencies of TN removal and nitrification were 96.6 and $70.0\%$, respectively. The removal efficiency of chemical oxygen demand (COD) was $63.7\%$, which was increased by $20\%$.

• 한국토양비료학회지
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• 제33권5호
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• pp.369-375
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• 2000

밭 토양 특히 시설재배 토양의 질소시비량을 결정하기 위한 효율적 검정법으로 확인된 $NO_3-N$의 간이 검정법을 개발하기 위하여 Hanna Ion Specific meter를 이용한 비색법과 Test strip Reflectometer를 이용한 측정법을 선정하고, 실험실 분석법인 Specific Ion Meter에 의한 이온 전극법 및 Kjeldahl 증류법과 함께 비교 분석하였다. 평가방법은 토양중 $NO_3-N$ 함량이 $25mg\;kg^{-1}$과 $55mg\;kg^{-1}$인 두 토양에 대하여 각 분석방법을 7반복씩 수행하여 표준편차를 비교하였고, 두 토양에 $NO_3-N$ 표준용액을 첨가하여 $NO_3-N$ 함량이 각각 100, 150, 200, 250, $300mg\;kg^{-1}$인 표준농도 계열에 대하여 7반복으로 분석하여 회수율을 비교하였다. 또한 $NO_3-N$ 함량이 $10mg\;kg^{-1}$에서 $340mg\;kg^{-1}$으로 분포되는 시설재배 토양 20개 시료에 대하여 3반복씩 분석하여 $NO_3-N$ 농도에 따른 측정치의 신뢰도를 비교하였다. 분석방법에 따른 측정치의 신뢰도와 회수율은 이온 전극법이 가장 양호하였고 Kjeldahl 증류법, Test strip 간이법, Hanna 비색법의 순이었다. 간이 검정법에 따른 비교에서 Hanna 비색법은 낮은 농도와 높은 농도에서 큰 오차를 보였으나 Test strip 간이법은 실험실 정밀분석법인 이온 전극법 및 Kjeldahl 증류법과 버금가는 신뢰도와 95% 이상의 회수율을 보였다. 따라서 단순한 분석절차와 짧은 분석시간을 고려해 볼 때 Test strip 간이법은 질소 시비량의 결정을 위한 현장의 간이 검정법으로 활용 가능한 것으로 평가되었다.

• 한국토양비료학회지
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• 제45권6호
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• pp.943-948
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• 2012

오이 시설재배지에서 질소 시비량 절감에 대한 호밀 환원 효과와 수량과 토양용액 중 질산태질소와의 관계를 평가하였다. 시험 처리구는 토양검정시비구 (NPK), 호밀을 $42.3Mg\;ha^{-1}$ 환원하여 질소비료 199 kg N $ha^{-1}$의 0, 50, 75, 100%의 4 수준으로 시비하여 시설재배지에서 오이 수량과 토양용액의 질산태질소 농도를 조사하였다. NPK의 오이수량은 $68.8Mg\;ha^{-1}$이었고, 호밀의 투입은 토양검정 질소시비량의 25-50%를 절감할 수 있었다. 오이재배 기간 중 NPK 토양용액의 평균 $NO_3$-N 농도는 $32.4mg\;L^{-1}$ 이었고, 호밀처리구의 0, 50, 75, 100%에서는 각각 26.0, 30.1, 41.4, $58.5mg\;L^{-1}$으로 질소시비량이 증가함에 따라 높아졌다. 이때 시설재배 오이수량과 토양용액 중 평균 $NO_3$-N 농도와의 수식 ($Y=49.3+0.63X-0.0034X^2$, $R^2=0.778^{**}$)은 유의성을 나타내었다. 따라서 오이 재배 중 토양용액 분석으로 질소 웃거름 시비량 결정이 가능할 것으로 판단되었다. 그러나 오이수량과 토양용액 $NO_3$-N 농도와의 관계에 대한 추가적인 실증연구가 필요할 것으로 사료된다.

• Journal of Biosystems Engineering
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• 제37권3호
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• pp.209-213
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• 2012

Purpose: This study was performed to develop a simple, disposable thin-film optical nitrate sensor. Methods: The sensor was fabricated by applying a nitrate-selective polymer membrane on the surface of a thin polyester film. The membrane was composed of polyvinylchloride (PVC), plasticizer, fluorescent dye, and nitrate-selective ionophore. Fluorescence intensity of the sensor increased on contact with a nitrate solution. The fluorescence response of the optical nitrate sensor was measured with a commercial fluorospectrometer. Results: The optical sensor exhibited linear response over four concentration decades. Conclusions: Nitrate ion concentrations in plant nutrient solutions can be determined by direct optical measurements without any conditioning before measurements.

• Journal of Photoscience
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• 제9권2호
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• pp.264-266
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• 2002

The absorption wavelength of the protonated retinal Schiff base can be controlled by the surrounding environment. An external anion is related to fine adjustment of the absorption wavelength. The addition of anion to retinochrome solution caused blue shift in spectra. The increase of the shift was dependent on the ion concentration. The large shift value was obtained as 20 nm at the saturated concentration of nitrate. The shift intensity for the nitrate addition exceeded that of chloride. Seemingly, it depends on the ionic strength or lyotropic character of the anion. However, neither of sulphate nor gluconate ion showed remarkable blue shift. These phenomena were accounted for with (1) delocalization of the positive charge in the conjugated polyene system, (2) ionic bonding strength between the counter ion (glutamate) and the proton, and/or (3) interaction of the added anion with the proton on Schiff base.

• 한국응용과학기술학회지
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• 제10권1호
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• pp.23-29
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• 1993

Transesterification reaction between dimethyl phthalate and ethylene glycol was kinetically investigated in the presense of various metal nitrate catalysts at $170^{\circ}C$. The reaction rates measured by the amount of distilled methanol from the reaction vessel. The transesterification reaction was carried out under the first order conditions respect to the concentration of dimethyl phthalate and catalyst, respectively. The over all order was 2nd. By Arrhenius plot, the activation energy was calculated as 17.4kcal/mole and 17.2kcal/mole on the transesterification reaction with zinc nitrate and lead nitrate, respectively. Apparent rate constant, k' was appeared linear about concentration of catalyst.

• 한국염색가공학회지
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• 제21권2호
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• pp.14-21
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• 2009

In this article, silk fabric was treated with silver nitrate ($AgNO_3$) as oxidizing agent, with conditions such as concentration, and treating time, and subsequently treated with reducing agents such as sodium boron hydride ($NaBH_4$) and sodium sulfide ($Na_2S$) to obtain cathodic coloration. After coloration of silk fabric, dyeing properties (K/S value), colorfastnesses such as wash, rubbing and light, and antibacterial activity property were examined. $AgNO_3$ treating time and reducing time did not influence K/S value, whereas the pH value at alkaline region showed a high K/S value of silk fabric. The cathodic colorations of silk fabric with both of reducing agents at $30^{\circ}C$ have excellent color fastnesses. Also the high antibacterial activities were obtained by the treatment with silver nitrate even at 1% of lower concentration.

• Journal of Pharmaceutical Investigation
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• 제26권4호
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• pp.263-271
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• 1996

Sulconazole nitrate(SCN), an imidazole derivative which has been effective in the treatment of dermatophytosis, tinea versicolor and candidiasis, was formulated as a gel containing drug, poloxamer 407, ethanol and propylene glycol. The resulting SCN gels were evaluated with respect to their viscosity, drug release rate, skin permeation rate. The apparent viscosity of SCN gel increased in proportion to poloxamer 407, drug and propylene glycol concentration. In case ethanol was added, the apparent viscosity decreased. The drug release rate of SCN gel increased in proportion to temperature and ethanol concentration. But the drug release rate decreased as the concentration of poloxamer 407 increased. The increase of drug concentration induced nonlinear increase of drug release rate. When propylene glycol was added at the level of 10%, the drug release rate increased but from 15% it decreased. The skin permeation rate decreased in high concentration of poloxamer 407. The skin permeation rate of SCN gel containing 15% ethanol increased about twice than that of gel without ethanol. The increase of drug concentration induced nonlinear increase of skin permeation rate. When propylene glycol was added at the level of 10%, the skin permeation rate increased but from 15% it decreased.