• Journal of Biosystems Engineering
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• 제24권6호
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• pp.479-486
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• 1999

A measurement method for the deposition amount of spray, using tracer and spectrophotometer was developed. Food colors was selected as tracer, because it was cheep and easily treatable. Using NIRS(Near Infrared Reflection Spectrophotometer), regression curves between absorbance spectrum and concentration of the tracer were obtained. Yellow food colors showed the peak of spectrum at 452nm, and absorbance of peak showed a tendency to increase as concentration increased. Also, the possibility of concentration control by heating was investigated.

• 약학회지
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• 제30권4호
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• pp.185-192
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• 1986

Authors developed the computer application program (language: APPLE SOFT BASIC) for derivative spectrophotometry. By means of this program, derivative of spectral absorbance with respect to wavelength is recorded versus wavelength. To try this program in connection with spectrophotometer system, the authors have done the simultaneous quantitation of pyridoxine center dot HCl and nicotinamide in the mixture, and the result was compared with that of absorbance method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 D
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• pp.1358-1360
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• 1998

In this paper, organic thin film LED(light emitting diode) having ITO glass/$Alq_3$/Al structure using an $Alq_3$ was fabricated by the vacuum evaporation and the absorbance, wave length, 1-V characteristics were investigated. Electroluminescence of green and wavelength of 510[nm] were observed in this device. We observed absorbance form 320[nm] to 430[nm] and knew unstability of $Alq_3$ material as light emitting device.

• Journal of Photoscience
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• 제11권2호
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• pp.83-87
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• 2004

A porphyrin compound containing a crown ether moiety (Por-Crown) and its zinc complex (ZnPor-Crown) have been prepared and the effect of the addition of alkali metal on their fluorescence has been investigated. As alkali metal cations were added, the absorption and fluorescence maxima did not change. However, the absorbance and intensity of fluorescence increased dramatically. Among the alkali metal cations tested, addition of K$^{+}$ and Cs$^{+}$ showed strongest enhancement of absorbance and fluorescence intensity of Por-Crown and ZnPor-Crown.own.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.439-442
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• 1998

In this paper, organic thin film LED(light emitting diode) having ITO glass/Alq$_3$/Al structure using an Alq$_3$ was fabricated by the vacuum evaporation and the absorbance, wave length, I-V characteristics were investigated, Electroluminescence of green and wavelength of 510[nm] were observed in this device. We observed absorbance form 320[nm] to 430[nm] and knew unstability of Alq$_3$ material as light emitting device.

• 약학회지
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• 제29권4호
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• pp.220-222
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• 1985

Rifampicin reacts with cupric ion to produce rifampicin-Cu(II) chelate (2:1) at pH 6.5, which can be extracted with methylisobutylketone (MIBK). Therefore, rifampicin can be quantitatively, determined by measuring the quantity of Cu(II) in the organic phase by atomic absorption spectrophotometry. Because higher absorbance ratio was obtained in pH 6.0~7.0, buffer solution at pH 6.5 was used in this measurement. Linear relationship was found between absorbance and concentration in the range of 1.0~4.0${\times}10^{-4}M$. This method might be applicable to the determination of rifampicin in the preparations.

• Bulletin of the Korean Chemical Society
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• 제12권3호
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• pp.262-264
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• 1991

An anomalous absorbance-temperature profile of calf thymus DNA, having a hypochromic trough just before the rise the $T_m$-region phase, occurs at the spermine concentration where the DNA collapses into a compact structure. The trough phase can be eliminated by the addition of ethidium bromide and also by a hydrophobic environment.

• 한국식품영양과학회지
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• 제23권4호
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• pp.604-613
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• 1994

Hydrophilic brown pigments(HBPs) produced during fermentation and aging the domestic Meju and Doenjang were separated by dialysis and chromatography , and their antioxidant activity were measured . The chemical properties of HBP were determined by UV and IR spectrophotometry. HBPs contents were found to be 93.1 mg/g and 183.2mg/g in Meju fermentated for 30 days and 80 days , respectively. The ratio of dialysate to diffusate of the HBPs were appeared to be 70 : 30 and 87 :13 in the Meju fermented for 30 days and 80 days, respectively. and the rtio in the Doenjang aged for 60 days was 91 :9 , indicating that dialysate slowly days, respectively, and the ratio in the Doenjang aged for 60 days was 91 : 9, incidatin that dialysate slowly increased by the fermentation . Both portion exhibited strong antioxidant activity, but more stronger antioxidant activity was found in the dialysate. DEAE-celluose column chromatography showed that dialysate contained more materials eluted by 0.01-0.03M HCI solution than 0.01M acetate buffer, but diffusate showed opposite results. The degree of browning reaction and antioxdiant activity found in the fraction eluted by HCI solution was stronger than that of the fraction eluted by acetate buffer. The fraction eluted from DEAE-cellulose column chormatogrphy was further fractionaged by TLC and found that strong antioxidant activity was present in the fractions which did not possess fluorescenece and showed a negative ninhydrin reaction. TLC fractions of HCI eluant in Meju exhibited a strong absorbance at 260-280nm, but most of other fractions did not show any absorbance at UV region. TLC fractions from dialysate and diffusate showed fairly identical IR spectrum with absorbance at 3400cm-1, 2800cm-3000cm -1, 1600cm, -1 1400cm-1 and 1100 cm-1 , however, in addition to these absorbances, the spectrum from HCI eluant of Meju exhibited a strong absorbance at 1750cm , indicating the carbonic acid or carbonate ester.

• 한국응용과학기술학회지
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• 제35권1호
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• pp.292-298
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• 2018

본 연구는 멍게 껍질을 100.0 % 에탄올 용매로 추출한 후 DMSO로 희석하여 색소안정성을 평가하였다. pH에 따른 흡광도와 색차계 값을 측정한 결과 pH 7.0에서 흡광도와 색도의 ${\pm}a$값이 가장 안정하게 나타났다. pH 3.0에서 흡광도의 감소가 나타났고 색도의 ${\pm}a$값이 감소하여 멍게 껍질 색소는 pH가 중성에 가까울수록 변색방지의 효과가 있을 것으로 판단된다. 항산화제 첨가시 색소의 흡광도가 증가하였으며 ${\alpha}-tocopherol$과 Glutathione이 가장 우수한 효과를 나타내었다.

• 한국환경보건학회지
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• 제40권2호
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• pp.137-146
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• 2014

Objectives: Feasibility of electrochemical oxidation of the aqueous non-biodegradable wastewater such as cationic dye Rhodamine B (RhB) has been investigated in an electrochemical reactor with solid polymer electrolyte (SPE). Methods: Nafion 117 cationic exchange membrane as SPE has been used. Anode/Nafion/cathode sandwiches were constructed by sandwiching Nafion between two dimensionally stable anodes (JP202 electrode). Experiments were conducted to examine the effects of applied current (0.5~2.0 A), supporting electrolyte type (0.2 N NaCl, $Na_2SO_4$, and 1.0 g/L NaCl), initial RhB concentration (2.5~30.0 mg/L) on RhB and COD degradation and $UV_{254}$ absorbance. Results: Experimental results showed that an increase of applied current in electrolysis reaction with solid polymer electrolyte has resulted in the increase of RhB and $UV_{254}$ degradation. Performance for RhB degradation by electrolyte type was best with NaCl 0.2 N followed by SPE, and $Na_2SO_4$. However, the decrease of $UV_{254}$ absorbance of RhB was different from RhB degradation: SPE > NaCl 0.2 N > $Na_2SO_4$. RhB and $UV_{254}$ absorbance decreased linearly with time regardless of the initial concentration. The initial RhB and COD degradation in electrolysis reaction using SPE showed a pseudo-first order kinetics and rate constants were 0.0617 ($R^2=0.9843$) and 0.0216 ($R^2=0.9776$), respectively. Conclusions: Degradation of RhB in the electrochemical reactor with SPE can be achieved applying electrochemical oxidation. Supporting electrolyte has no positive effect on the final $UV_{254}$ absorbance and COD degradation. Mineralization of COD may take a relatively longer time than that of the RhB degradation.