• The Korean Journal of Zoology
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• v.35 no.4
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• pp.466-473
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• 1992

Storage protein-1 (SP-1) of Gallerio mellonella was identified in hemolvmph and fat body by electrophoresis. SP-1 was purified from hemolvmph by KBr density gradient ultracentrifugation , DEAE-cellulose (DE52) ion-exchange chromatography, and gel permeation chromatography (Sephadex G-200). Purity of SP-1 was confirmed by Non-SDS PAGE and electron microscope. SP-1 is 9.4 nm in diameter and regular octahedron in shape. SP-1 has isoelectric point of 5.7 and native molecular weight of 365 K dalton and is composed of one type of subunit with molecular weight of 82 K dalton. Ttiacylslvcerol and phospholipid were found to be maior lipid components in SP-1.

• Bulletin of the Korean Chemical Society
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• v.29 no.7
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• pp.1332-1334
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• 2008

Stable crystalline 1-Benzyl-4-aza-1-azonia-bicyclo[2.2.2]octane tribromide (BABOT), can be readily synthesized from the reaction of the corresponding bromide with $HNO_3$ and aqueous KBr. Selective Oxidation of a variety of dialkyl and alkyl Aryl sulfides to the corresponding sulfoxides in high yield was achieved by this reagent in solution ($CH_3CN/H_2O$) and solvent free conditions. The reaction proceeds under neutral and mild conditions and can be carried out easily at room temperature with regeneration of BABOT. In this method purification of products is straightforward and no over oxidation to sulfone was noted.

• Journal of the Korean Chemical Society
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• v.14 no.3
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• pp.263-269
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• 1970

A theory of surface tension developed by using the approximation that the surface of liquids consists of a monomolecular layer has been applied to the molten salts (NaCl, KCl, NaBr, KBr) and the strong electrolyte solutions. By considering that the ionic forces are the long-range forces and with the use of the partition functions developed, the surface tension of molten salts and strong electrolyte solutions has been calculated. The results show good agreement between theory and experiment at various temperatures and over a wide concentration ranges (0.1-4.0m)

• Elastomers and Composites
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• v.13 no.2
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• pp.99-107
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• 1978

The measurement of the infrared absorption spectrum of supporting reinforcing filler which is oltained from the domestic area of Korea, Japan and U.S.A., is used by the method of KBr pellet. As a result of experiment, each absorption fond of the filler had appeared differently, because of each filler is consisted of different chemical composition, different crystalline form, different method of preparation, and the different ways of use etc. According to the above phenomena, each filler seems to have a different characteristic infrared absorption band, We can find what filler is used for sample rubber.

• Proceedings of the Korean Fiber Society Conference
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• 1996.10a
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• pp.478-483
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• 1996

다관능성 에폭사이드 PPE(Polyglycerol Polyglycidyl Ether)를 양모섬유에 처리하였을 때 부가반응의 특성을 고찰하였다. 에폭사이드 PPE에 의한 부가반응이 촉매작용을 하는 NaSCN 존재하에서 이관능성 EGDE보다 높은 부가율을 얻을 수 있었다. 에폭사이드 부가반응은 고온에서 반응이 잘 일어나며 에폭사이드 처리욕의 pH는 반응 초기 급격히 상승했다가 이후 점차 초기 값까지 안정화된다. 처리한 양모섬유를 FTIR의 KBr-pellet법과 ATR법에 의해 분석하여 absorbance ratio를 비교하였을 때 부가반응은 표면으로의 그라프트 반응이 우세함을 알 수 있었으며 이러한 결과는 SEM 관측을 통하여 확인할 수 있었다. Performic acid/Ammonia solubility를 에폭사이드 처리 양모섬유에 적용하여 용해도 변화를 보았을 때 부가된 양이 많을수록 용해도 값이 감소하며 특히 15.6%를 중심으로 용해도 변화가 둔화되었다. 아미노산 분석으로 에폭사이드가 반응한 아미노산이 cystine임을 알 수 있었으며 단백질 사슬간에 가교반응이 이루어졌음을 확인할 수 있었다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1990.10a
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• pp.105-107
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• 1990

In this study, we prepared plasma polymerized thin films as changing the composition rate of the Ar/CO$_2$, 0 to 100%, for analysing the influence of CO$_2$ gas in plasma polymerization. Power source was the RF frequence (13.56MHz), the monomers were styrene and MMA (Methyl-methacrylate), and substrates were glass and KBr(or NaCl) for IR spectroscopy. The molecular structure of plasma polymerized organic thin films was examined by IR, FT-IR, Gas chromatography and so forth.

• YAKHAK HOEJI
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• v.13 no.2_3
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• pp.51-56
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• 1969

In quantitative analysis of sulfonamide drugs by means of infrared Spectrophotometry, the author tried to analyse Sulfamethoxydiazine and Sulfamethoxypyridazine in their Pharmaceutical Preparations. By the survey of infrared absorption spectra of Sulfamethoxydiazine and Sulfamethoxypyridazine. We found quantitative properties at the peaks of wave number 1150 cm$^{-1}$ (Sulfamethoxydiazine) and 1090 cm$^{-1}$ (Sulfamethoxypyridazine) in the spectra. These peaks obey Beer's Law in a range of 50-150 ug for Sulfamethoxydiazine and 70-350 ${\mu}$g for Sulfamethoxypyridazine in 300 mg KBr disc. By this method, Sulfamethoxydiazine and Sulfamethoxypyridazine could be analyzed less than 2% error.

• YAKHAK HOEJI
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• v.50 no.6
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• pp.393-397
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• 2006

The synthesis of new 3-substituted 7-halocephalosporanates was described. 7-ACA was reacted with thiols at pH 6.5${\sim}$6.8 to afford the 3-substituted 7-ACA (1), which was treated with diphenyldiazomethane to give diphenylmethyl 7-aminocephalosporanate (2). The Halogenation of 7-aminocephalosporanate (2) with NaNO$_2$, KBr and H$_2$SO$_4$ gave 7-bro-mocephalosporanate (3) and with NaNO$_2$, HCI gave 7-chlorocephalosporanate (4). Diphenylmethyl cephalosporanate (2${\sim}$4) were deprotected by AIC1$_3$ in anisole and neutralized to give the sodium cephalosporanate (5${\sim}$7).

• Analytical Science and Technology
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• v.36 no.6
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• pp.315-323
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• 2023

This study is to quantify α-quartz, cristobalite and kaolinite using by FTIR in respirable dust generated in the mining workplace. Various minerals in mines can interfere with peaks when quantifying respirable crystalline silica by FTIR. Therefore, for accurate quantification, it is necessary to remove interfering substances or correct the peaks that cause interference. To confirm the peaks occurring in α-quartz, cristobalite and kaolinite, each standard material was diluted with KBr and scanned in the range of 400 cm^-1 to 4000 cm^-1 using by FTIR. As a result of scanning the analytes, it was decided to use the peaks of 797.66 cm^-1 and 695.25 cm^-1 for α-quartz, 621.58 cm^-1 for cristobalite, and 3696.47 cm^-1 for kaolinite. When the above materials are mixed, interference occurs at the peak for quantification, which is corrected by the calculation formula. The analysis of the mixture of α-quartz and cristobalite shows the average bias (%) of 2.64 (corrected) at α-quartz (797.66 cm^-1), 5.61 (uncorrected) at α-quartz (695.25 cm^-1) and 1.51 (uncorrected) at cristobalite (621.58 cm^-1). The analysis of the mixture of α-quartz and kaolinite shows the average bias(%) of 1.79(corrected) at α-quartz (797.66 cm^-1), 3.92 (corrected) at α-quartz (695.25 cm^-1) and 2.58 (uncorrected) at kaolinite (3696.47 cm^-1). The analysis of the mixture of cristobalite and kaolinite shows the average bias (%) of 2.15 (corrected) at cristobalite (621.58 cm^-1), 4.32 (uncorrected) at kaolinite (3696.47 cm^-1). The analysis of the mixture of αquartz and cristobalite and kaolinite shows the average bias (%) of 1.93(corrected) at α-quartz (797.66 cm^-1), 6.47 (corrected) at α-quartz (695.25 cm^-1) and 1.77 (corrected) at cristobalite (621.58 cm^-1) and 2.61 (uncorrected) at kaolinite (3696.47 cm^-1). The experimental results showed that the deviation caused by peak interference by two or three substances could be corrected to less than 6 % of the average deviation. This study showed the possibility of correcting and quantifying when various interfering substances that are difficult to remove are mixed.

• Journal of Life Science
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• v.21 no.5
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• pp.761-765
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• 2011

Salt stability of enzymes is a crucial practical factor in the food industry. Previously, leucine aminopeptidase (LAP) was purified from Bacillus sp. N2. Here, we present the salt effect of LAP using synthetic substrates. LAP had a hydrolytic activity for L-leucine-${\rho}$-nitroanilide in high concentrations of NaCl (up to 4 M), but not for other neutral salts (LiBr, LiCl, NaBr, KBr, and KCl). It hydrolyzed various synthetic di-peptide substrates with hydrophobic and hydrophilic amino acids at the C-terminal Xaa region, in the presence of 0-4 M NaCl. The result indicated that the hydrolytic action of LAP is not dependent on the hydrophobicity of the amino acid side chain at the scissile bond of the substrate. Remarkably, the hydrolytic activity of LAP was 1-3 folds higher than those of other LAPs and aminopeptidases in 4.5 M NaCl, suggesting that NaCl-tolerant LAP might be used in the food industry as cheese and anchovy sauce.