• 한국농공학회:학술대회논문집
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• 한국농공학회 2001년도 학술발표회 발표논문집
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• pp.421-425
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• 2001

Among the many parameters describing water quality, total nitrogen content(TN) is regarded as important one in relation to water quality management of the waterbodies for its role in eutrophication process. This study evaluated for accuracy, convenience and promptness of nitrogen analysis methods : (1)UV spectrophotometric method, (2)summation method, (3)cadmium reduction method. And, the detection limit of each method was calculated using EPA method. The UV spectrophotometric method after oxidation appears to be more convenient and accurate in determination of the TN contents than the summation method and cadmium reduction method. The summation method is necessary to separate determinations of the organic nitrogen, ammonia, nitrite, and nitrate. And, because summation method has many other methods for each contents, it can be detected for wide range of concentration.

• 약학회지
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• 제53권5호
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• pp.235-240
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• 2009

The interaction of cadmium (II) ion with quercetin was investigated in aqueous solution at different pH. The quercetin/cadmium stochiometries for cadmium (II) binding have been determined by UV-vis spectrophotometric method. The complexation of Cd(II) ion with 54.72 ${\mu}M$ quercetin (A=1.00793) was formed in 0.2 M $NH_3-0.2$ M $NH_4Cl$ (pH 8.0) buffer solution. 1:1 Cd(II)-complex had a maximum absorbance and showed the bathochromic shift of the long-wavelength band of the UV-vis spectra in the alkaline pH when interacted with quercetin in buffer solution. These results suggest that Cd(II)-quercetin complex has the optimal condition of chelation in basic buffer solution.

• 대한화학회지
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• 제9권1호
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• pp.45-48
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• 1965

Stability constant, composition of copper (II)-oxamidoxime complex were determined by spectrophotometric method. The ratio of copper (II) and oxamidoxime in the above complex was 1 : 1, and its stability constant was calculated to be $2.4{\times}10^{22}$. The complex solution gave constant absorbancy between the pH range of 4.5 to 6 at 600 $m{\mu}$ in which Beer's law applicable in the concentration range of 0.3 to 2.0 ppm studied in this work. It was noted that some metals such as Fe(III), Ni(II), Co(II), U(VI) interfere copper determination by this method.

• 대한화학회지
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• 제9권1호
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• pp.33-36
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• 1965

5-Acetyl-8-hydroxyquinoline 의 酸解離定數를 $25^{\circ}C({\mu}$=0.1)에서 分光光度法과 pH滴定法에 依하여 測定하였다. 두 方法에 의하여 얻은 $pK_1$은 近似하게 一致하였으며 pK값은 8-hydroxyquinoline의 該當 pK값보다 작다. 그것은 acetyl group의 芳香族環에 대한 電子吸引性에 基因한 結果라고 생각한다.

• 대한화학회지
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• 제15권6호
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• pp.378-384
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• 1971

A new analytical reagent 8-(p-ethylbenzenesulfonamido)quinoline(EBSQ) has been synthesized, and identified its structure. EBSQ forms copper chloroform-soluble complex in a basic solution (pH = 7.5∼10.5). The other optimum conditions for the spectrophotometric study of Cu-EBSQ have been established at 380 $m{\mu}$. Beer's law is followed in the concentration range of 0~44.5 ${\mu}g$ per 10 ml of chloroform. The composition of complex has been found to be $Cu(EBSQ-H)_2$and the over-all instability constant is calculated to be $1.22{\times}10^{-7}$. The absorption coefficient of the $Cu(EBSQ-H)_2$ complex is ${\varepsilon}$ = 15,800.

• 대한화학회지
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• 제7권4호
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• pp.299-303
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• 1963

A method of the colorimetric determination of titanium has been developed, based on the fact (IV) forms a stable blue complex with methylthymolblue(MTB) which is suitable for spectrophotometric determination of titanium in the concentration range of 0.2 to 22 $\mu$g per ml as $TiO_2$. The determination was carried out in the solution of pH range of 2.6 to 3.6, and the absorbancy of complex was at 600m$\mu$ with Coleman spectrophotometer. Titanium forms a 1:1 complex with MTB, which has a molar absorptivity, $1.1{\times}10^4$ at 600m\mu$. The effects of hydrogen ion concentration, reagent concentration, stability of complex, and hydrolysis were studied. Most of cations do not interfere seriously; however, many of anions such as oxalate, citrate, phosphate, chloride interfere in this determination.

• 생약학회지
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• 제30권1호
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• pp.54-58
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• 1999

A method using coloric and spectrophotometric detection have been developed for the identification of the tertiary or quaternary alkaloids contained in Corydalis tuber and its preparations. The principle is based on the formation or decomposition of complex compounds. The complex compound of the tertiary and quaternary alkaloids have been formed by adding tetrathiocyanatocobaltate [II] ion to the test soln. Diverse crude drugs were screened using this method and the results indicated that isoquinoline, aconitine-type alkaloids in crude drugs can be readily detected. The method is simple, convenient, reproducible and applicable to the verification of the crude drug Corydalis tuber and its preparations.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1851-1853
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• 1996

In this paper the criteria for insulating oil condition of pole transformer were suggested by applying the UV-Visible spectrophotometric method. Ageing of insulating oil caused the change in absorbances of oil os well os the deterioration of electrical properties of oil. By comparing the electrical properties such as $tan{\delta}$ and breakdown voltage with the UV-Visible absorbances of oil, criteria for absorbance values determining oil condition were established. This UV-Visible spectrophotometric method might be applied in ageing analysis of oil and be expected to replace the current method.

• Asian-Australasian Journal of Animal Sciences
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• 제14권9호
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• pp.1321-1325
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• 2001

Color characteristics of pig ${\times}$ wild boar meat were determined with a fiber-optic spectrophotometer. The spectrophotometric characteristic of reduced-myoglobin observed after cutting immediately changed to the spectrophotometric characteristic of oxymyoglobin after 15 minutes of cutting. The spectrophotometry at 400 to 700 nm after 30, 45, 60, 90 and 120 minutes of cutting changed slightly. Compared with M. longissimus thoracis, M. rhomboideus had higher reflectance around 400 nm and from 650 to 1,100 nm and M. spinalis was lower in the visible light region after 60 minutes of cutting. The pig ${\times}$ wild boar meat was similar in reflectance shape with pork but was lower in intensity. The differences depended on the anatomical location. The M. rhomboideus from pig ${\times}$ wild boar had greatly lower reflectance than that from pig, the M. longissimus thoracis reflectance was lower, but M. spinalis reflectance hardly differed. These results showed that pig ${\times}$ wild boar meat had no special characteristic of blooming but had distinguishing characteristic of meat color among anatomical locations.

• 대한화학회지
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• 제18권6호
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• pp.415-420
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• 1974

特別한 裝置나 複雜한 操作없이 簡單하고 迅速한 brucine 法에 依한 窒酸이온의 吸光光度 定量法을 定하였다. 檢液을 brucine 試液과 30N 黃酸으로 $60^{\circ}C$<\tex>에서 30分間 反應시키면 安定하고 再現性이 좋은 發色을 얻을 수 있으며, 410nm에서 窒酸性窒素의 濃度가 0.07ppm부터 0.6ppm까지 吸光度와 直線的 關係가 있다. 또 反應系에서 吸光綜의 數는 단 하나임을 確認하였다. 妨害이온들중 亞窒酸이온은 메탄올로서 除去할 수 있다.