• Bulletin of the Korean Chemical Society
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• v.13 no.1
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• pp.17-20
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• 1992

Photoionization processes of TMPD in $H_2O$ and $D_2O$ were studied, by measuring steady-state absorption, emission, fluorescence excitation spectra, and fluorescence lifetimes on picosecond time scale. The steady-state absorption spectra showed that there exists a cation-ion pair (Wurster's Blue) in $H_2O$ and in $D_2O$ in the electronic ground state. Temperature and excitation wavelength dependence were also studied and the results show that the photoionization reaction in water is an activated process and the fluorescence lifetime is independent of the vibrational excess energy in the uv excitation range of 283-310 nm.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05b
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• pp.283-288
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• 1997

고 준위 방사성 액체 패기물의 옥살산 침전 공정을 통하여 침전여액이 발생된다. 이 침전여액에는 옥살산과 같은 유기 물질이 함유되어 있으며 이 물질의 제거는 방사성 폐기물의 긍극적인 처리 처분에 대단히 중요하다 본 연구는 모의 침전여액을 제조하고 이로부터 옥살산 제거 연구가 두 가지 방법으로 수행되었다. 첫째 과산화수소를 이용한 제거 법으로서 침전여액 내 Ru$^{+4}$ 와 Fe$^{+3}$ 는 과산화수소를 자체 분해시키기 때문에 옥살산 제거를 방해함을 알 수 있었다 둘째는 NaOH를 용액 내 첨가하는 방법으로 pH증가에 따라 침전이 발생되면서 COD는 상당히 감소함을 보여주었다. 침전물은 $Na_2$C$_2$O$_4$로 확인되었고 pH9 이상에서 99%이상 감소함을 보여 주었다.다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.20 no.6
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• pp.283-288
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• 2010

Nanosized NiO powder was prepared by mixing an acid nickel salt and a base nickel salt and their reduction behavior was studied. Ni formate was employed as an acid salt and nickel hydroxide and basic nickel carbonate as base salts. One equivalent acid salt was mixed with 9 equivalent base salt. The mixture of the formate and the carbonate produced ~100 run spherical NiO powder by heat treatment at $750^{\circ}C$/2 h, but the mixture of the formate and the hydroxide gave rise to ~100 nm pseudo spherical NiO powder by heat treatment at $600^{\circ}C$/2 h and grew fast to give pseudo cubic crystals of 100~600 run by heat treatment at $750^{\circ}C$/2 h. Reduction by hydrogen gas proceeded much faster for the one with the hydroxide than that with the carbonate to give porous body with well grown necks. Their behavior was studied by analysis of TG/DSC, XRD, and SEM.

• Food Science of Animal Resources
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• v.23 no.3
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• pp.278-283
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• 2003

Feasibility tests on using liposomes for detecting food-borne pathogenic bacteria were studied with E. coli 0157:H7 as a model analyte. lmmunoliposomes, whose surface was conjugated with anti-E. coli 0157:H7 IgG and which encapsulated the marker dye, sulforhodamine B, were used for the detection label. Among the feasibility tests, the first test was to use a test-strip on which antibodies to anti-E. coli O157:H7 IgG were immobilized. In this format, immunoliposomes that did not bind to E. coli O157:H7 in sample were captured and then exhibited a visible signal which was inversely related with the number of E. coli O157:H7 in sample. The second test was a direct liposome assay followed by immunomagnetic separation. In this format, immunoliposomes which were bound to E. coli O157:H7 were lysed with detergent and produced a signal which was proportionally related with the number of E. coli O157:H7 in sample. The results from both formats indicate that liposomes can be utilized as a detection label.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.2
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• pp.275-283
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• 2012

MCM-41(Mobil's Composition of Matter-41) and expanded graphite(EG) were investigated as potential adsorbents for heavy metal ions including Pb(II), Cu(II) and Ni(II) in various aqueous chemistries. MCM-41 showed shorter equilibrium times and higher adsorption capacities for all three heavy metal ions compared to expanded graphite. The adsorption of three heavy metal ions was significantly affected by the solution pH due to the competition with $H_{3}O^{+}$ at lower pH and precipitation at neutral or higher pH. Adsorptions of heavy metal ions onto MCM-41 and expanded graphite were successfully described with the pseudo-second-order model. During the competitive adsorption of three heavy metal ions, the selectivity of Pb(II) was highest and almost same selectivity was observed with Cu(II) and Ni(II) when MCM-41 was used as an adsorbent, while the expanded graphite exhibited the highest selectivity to Pb(II), followed by Ni(II) and Cu(II).

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.3
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• pp.275-283
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• 2012

This paper presents a design method of a robust tracking controller satisfying multiple constraints using genetic algorithm. A robust $H_{\infty}$ constraint with loop shaping is used to address disturbance attenuation with error limits and a loop gain constraint is considered so as not to enlarge the tracking loop gain and bandwidth unnecessarily. The robust $H_{\infty}$ constraint is expressed by a matrix inequality and the loop gain constraint is considered as an objective function so that genetic algorithm can be applied. Finally, a robust tracking controller can be obtained by integrating genetic algorithm with LMI approach. The proposed tracking controller design method is applied to the track-following system of an optical DVD recording drive and is evaluated through the experimental results.

• The Korean Journal of Ecology
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• v.20 no.4
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• pp.275-283
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• 1997

Vertical and temporal characteristics of desalinized reclaimed soil were analyzed from reclaimed coastal land on the western coast of Korea. Of the vertical changes during desalting, pH valuse were the lowest at the topsoil without regard to reclaimation time. The content of C1 were designated as the early period (the first 2-4 years) which decreased exponentially and the later period(the last 5-7 years) which was almost constant, from top to down. In temporal changes of the soil attributes, pH values increased for 5 years and decreased at 6 year after reclamation. Chlorine leaches more rapidly than Na does, K and Ca are constant but Mg increases as time elapsed after reclamation. Sometimes the content of Ca and K in the reclaimed soil are of higher concentration than that of the seawater after reclamation. During desallinization as exemplified by decreasing EC of the soil, Cl and Na are rapidly leached, but K, Ca and Mg are somewhat enhanced. The ration of Na/Cl in the soil equals 1 when the EC registers 5 mmho and then increases dramatically as the EC decreases. Rapid leaching of $Cl^{-}$ elicits an increasing pH valus. The electrostatic balance of the soil is achived by replacement of $Cl^{-}$ with $OH^{-}$ until stationary or until a decreasing pH value is reached again.

• KSBB Journal
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• v.14 no.3
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• pp.279-283
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• 1999

We have compared the breakthrough behavior of lysozyme contained in fresh han egg white on various cation exchagers, and the adsorbent, known by the trade name Cellufine C-200 (Amicon), has shown the best performance. The effects of ion strength, pH, and linear flow rate on the breakthrough behavior were examined using the Cellufine C-200 adsorbent. The optimal conductivity, pH and linear flow rate were determined from the breakthrough behavior and found to be 2.75 mS/cm, 7.0, and 0.635 cm/min, respectively.

• Korean Journal of Food Science and Technology
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• v.24 no.3
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• pp.279-283
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• 1992

This study was undertaken to investigate the effects of added phytate and pH on the solubility and in vitro digestibility of low-phytate rapeseed protein isolate. Phytate content of low-phytate rapeseed protein isolate was 1.5%, as a result of 66% removal from defatted rapeseed flour and the protein: phytate ratio was 58:1. Solubility of rapeseed protein isolate at pH 2.0 and pH 11.5 was much higher than near the isoelectric point, pH 5.0. It's solubility was lowered by adding an increased amount of phytate especially at pH 2.0. The inhibitory effect of phytate toward pepsin digestibility of rapeseed protein isolate decreased by the increasing amount of phytate added. It is suggested that the production of low-phytate rapeseed protein isolate is necessary to improve the functionality and nutritional value in order to utilize it as food material.

• Journal of Sensor Science and Technology
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• v.23 no.4
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• pp.278-283
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• 2014

In this study, we propose an immunosensor using zinc oxide nanorods (NRs) inside PDMS channel for detecting the influenza A virus subtype H7N9. ZnO with high isoelectric point (IEP, ~9.5) makes it suitable for immobilizing proteins with low IEP. In this proposed H7N9 immunosensor structure ZnO NRs were grown on the PDMS channel inner surface to immobilize H7N9 capture antibody. A sandwich enzyme-linked immunosorbent assay (ELISA) method with was used 3,3',5,5' tetramethylbenzidine (TMB) for detecting H7N9 influenza virus. The immunosensor was evaluated by amperometry at various H7N9 influenza antigen concentrations (1 pg/ml - 1 ng/ml). The redox peak voltage and current were measured by amperometry with ZnO NWs and without ZnO NWs inside PDMS channel. The measurement results of the H7N9 immunosensor showed that oxidation peak current of TMB at 0.25 V logarithmically increased from 2.3 to 3.8 uA as the H7N9 influenza antigen concentration changed from 1 pg/ml to 1 ng/ml. And then we demonstrated that ZnO NRs inside PDMS channel can improve the sensitivity of immunosensor to compare non-ZnO NRs inside PDMS channel.