• 제목/요약/키워드: Determination method

검색결과 6,607건 처리시간 0.03초

인삼 산성다당체의 비색정량 방법과 그 추출조건 및 안정성 (Colorimetric Determination of Acidic Polysaccharide from Panax ginseng, its Extraction Condition and Stability)

  • 도재호;이형옥
    • Journal of Ginseng Research
    • /
    • 제17권2호
    • /
    • pp.139-144
    • /
    • 1993
  • The method for colorimetric determination of acidic polysaccharide from Panax ginseng was investigated. It is possible to apply the method of carbazole-sulfuric acid to determination of pectin, and also to measure the amount of pectin in the mixture of various high molemlu compounds such as starch. cellulose and gum, etc. When the method of carbazole-sulfuric acid was applied to determine the amount of acidic polysaccharide, optical density at 525 nm increased linearly with an increase in the concentration of pure acidic polysaccharide. Effective extraction temperature with water for the determination of the amount of ginseng acidic polysaccharide (GAP) was $80{\circ}C$. In order to separate or concentrate GAP it was appropriate to precipitate the extract only once with 80% ethyl alcohol. GAP was very stable at $100{\circ}C$ for 4 hrs in aqueous solution and between pH values of 5.0~ 12.0.

  • PDF

Determination of Methyl Bromide Used for the Preservation of Cultural Materials from Insects

  • Lee, Gil-Seung;Shin, Ueon-Sang;Shin, Ho-Sang
    • 한국환경보건학회지
    • /
    • 제28권4호
    • /
    • pp.27-30
    • /
    • 2002
  • A thermal desorption-gas chromatography/mass spectrometric method was developed for the determination of methyl bromide in fumes formed during preservation of cultural materials from insects. Methyl bromide in lunes was collected by drawing 10ι of air through the adsorbent tube filled with a solid adsorbent (Chromosorb). The air samples were analyzed by using a special thermal desorption device and GC/MS determination. The recovery of methyl bromide by air sampling was 88% and the detection limit of the assay was 0.1 pptv based upon assayed air of 10ι. The method was applied to the determination of fumed methyl bromide used for the preservation of papers in a library. The mean concentration of methyl bromide determined in a library was 280.2 $\pm$ 25.4 pptv.

變位 凍結法에 의한 應力擴大係數의 實驗的 決定法 (Experimental Determination of Stress Intensity Factors by Displacement Freezing Method)

  • 최선호;권재도;서인보
    • 대한기계학회논문집
    • /
    • 제7권4호
    • /
    • pp.434-440
    • /
    • 1983
  • For the determination of stress intensity factors, three methods have been used conventionally; the photoelastic method, the compliance method and the electrical resistance method. These methods, however, have common short coming upon experimental performance; the difficulty of cutting out sharp crack tips and arbitray crack forms similar to the practical one on the specimen. to eliminate this flaw, one of the author previously presented new methods, that is, for the determination of $K_{III}$ mode, the membrane analogy was applied and the slab analogy was used for the determination of $K_{I}$ and $K_{II}$ . The validity of this method was proved through the performance of a series of experiments of which theoretical solution are known.n.n.

Kinetic Spectrophotometric Determination of Trace Amounts of Sulfide

  • Barzegar, Mohsen;Jabbari, Ali;Esmaeili, Majid
    • Bulletin of the Korean Chemical Society
    • /
    • 제24권9호
    • /
    • pp.1261-1264
    • /
    • 2003
  • A method for the determination of trace amount of sulfide based on the addition reaction of sulfide with methyl green at pH 7.5 and $25{\circ}C$ is described. The reaction is monitored spectrophotometrically by measuring the decrease in absorbance of the dyestuff at 637 nm by the initial rate and fixed time method. The calibration graph is linear in the range 30-1200 ppb. The theoretical limit of detection was 0.014 ppm. Seven replicate analysis of a sample solution containing 0.70 ppm sulfide gave a relative standard deviation of 1.5%. The interfering effects of various ions on sulfide determination have been reported and procedures for removal of interference have been described. The proposed method was applied successfully to the determination of sulfide in tap and wastewater samples.

Comparison of Determination Methods of Amino Nitrogen in Salt-Fermented Anchovy Sauce

  • Cho Young-Je;Kim Tae-Jin;Choi Yeung-Joon
    • Fisheries and Aquatic Sciences
    • /
    • 제4권3호
    • /
    • pp.144-149
    • /
    • 2001
  • In other to establish the exact determination method of amino nitrogen (AN) in salt-fermented fish sauces, we determined the AN in fish sauces according to the measuring methods and also investigated the main factors influencing on determination method of AN. AN in salt-fermented anchovy sauce increased linearly as fermentation progressed, and was shown the highest amount measuring by the Formol method, followed by the trinitrobenzene sulfonic acid (TNBS) method and the Copper-salt method. AN concentration in anchovy sauces fermented for 12 months was $88.2\%$ and $77.6\%$ for the TNBS method and the Copper-salt method, respectively, on the basis of Formol method. The ratio of AN/total nitrogen (TN) in anchovy sauce fermented for 12 months was higher than that in commercial anchovy sauces. The determination of AN in anchovy sauce by the TNBS method was not affected by salt concentration, and slightly affected by heating. The effect of MSG on AN contents by Copper-salt method was shown higher than those by the Formol method and the TNBS method. The TNBS method was adaptable to measure the content of AN in fish sauce by this study.

  • PDF

실내외 위치측위를 위한 Fingerprint 기반 측정오차 감소 방안 연구 (A Study on Measurement Error Reduction of Indoor and Outdoor Location Determination in Fingerprint Method)

  • 권대우;이두용;송영근;장정환;이창호
    • 대한안전경영과학회지
    • /
    • 제13권1호
    • /
    • pp.107-114
    • /
    • 2011
  • Location-Based Service(LBS) is a service that provides a variety of convenience in life using location information that can be obtained by mobile communication network or satellite signal. In order to provide LBS precisely and efficiently, we need the location determination technology, platform technology and server technology. In this study, we studied on how we can reduce the error on location determination of objects such people and things. Fingerprint location determination method was applied to this study because it can be used at current wireless communication infrastructure and less influenced by a variety of noisy environment than other location determination methods. We converted the probability value to logarithmic scale value because using the sum of k probability values is not suitable to be applied to weight determination. In order to confirm the performance of suggested method, we developed location determination test program with Visual Basic 6.0 and performed the test. According to indoor and outdoor test results, the suggested stochastic method reduced the distance error by 17%, 18% and 9% respectively at indoor environment and 25%, 11% and 4% at outdoor environment compared with deterministic NN, kNN and kWNN fingerprint methods.

피크린 산에 의한 항히스타민제의 추출분광광도 정량 (Extraction Spectrophotometric Determination of Antihistamines with Picric Acid)

  • 신태용;엄동옥
    • 약학회지
    • /
    • 제37권2호
    • /
    • pp.119-123
    • /
    • 1993
  • A spectrophotomertic method is proposed for the determination of antihistamines. The method is based on solvent extraction of the ion pair formed between antihistamines and colored picric acid into chloroform. The binding state of antihistamines-picric acid complexes were presumed by IR and $^{1}$H-NMR spectra as intermolecular hydrogen bonding. This method was applicable to the determination of antihistamines in the pharamaceutical preparations.

  • PDF

Indirect Spectrophotometric Determination of Trace Quantities of Hydrazine

  • Haji Shabani, A.M.;Dadfarnia, S.;Dehghan, K.
    • Bulletin of the Korean Chemical Society
    • /
    • 제25권2호
    • /
    • pp.213-215
    • /
    • 2004
  • An indirect, sensitive and accurate method for the determination of trace amounts of hydrazine is described. The method is based on the oxidation of hydrazine by a known excess of iodate in the presence of hydrochloric acid. The unreacted iodate is used in the oxidation of hydroxylamine to nitrite. Sulfanilic acid is diazotized by the nitrite formed. The resulting diazonium ion is coupled with N-(1-naphthyl)ethylenediamine to form a stable azo dye, which shows an absorption maximum at 540 nm. Hydrazine can be determined in the range of 20-400 ng $mL^{-1}$ with a detection limit of 3.1 ng $mL^{-1}$. The relative standard deviation for 50, 200 and 400 ng $mL^{-1}$ of hydrazine is 2, 1.5 and 1.3%, respectively (n = 10). The method was applied to the determination of hydrazine in water samples.

Spectrophotometric Determination of Nitrite Based on Its Reaction with p-Nitroaniline in the Presence of Diphenylamine in Micellar Media

  • Afkhami, Abbas;Masahi, Shokofeh;Bahram, Morteza
    • Bulletin of the Korean Chemical Society
    • /
    • 제25권7호
    • /
    • pp.1009-1011
    • /
    • 2004
  • In the present work a very simple, sensitive and selective spectrophotometric method for the determination of nitrite in micellar media is described. The method is based on the color reaction of nitrite with p-nitroaniline in the presence of diphenylamine in acid media. In order to remove the extraction step, Triton X-100, a non-ionic surfactant was used as micellar media. The optimum reaction conditions such as acid concentration, reagents concentration and effect of time have been studied and the analytical characteristics of the method such as limit of detection, linear range and molar absorptivity have been obtained. The interference of some anions and cations was also tested. The method was applied to the determination of nitrite in real samples.

지모(Anemarrhena asphodeloides Bunge)의 근경으로부터 Anemarsaponin B의 분리 및 함량분석 (Isolation and Quantitative Determination of Anemarsaponin B from the Rhizomes of Anemarrhena asphodeloides Bunge)

  • 이주미;이승호;박정일;강신정;장승엽;이경순;손건호
    • 생약학회지
    • /
    • 제30권2호
    • /
    • pp.163-167
    • /
    • 1999
  • A method for isolation and qantitative determination of anemarsaponin B from the rhizomes of Anemarrhena asphodeloides has been developed. Isolation of anemarsaponin B was achieved by silica gel and RP-18 column chromatography. The HPLC method for quantitative determination of anemarsaponin B provided a method for standardization of the crude drug. It suggested that the content of anemarsaponin B in Anemarrhena asphodeloides is about 0.12-1.48%.

  • PDF