• Title/Summary/Keyword: sulfite

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Assessment of Maximum Use Levels and Estimation of Theoretical Maximum Daily Intake for 9 Food Additives in Korea by the Budget Method (Budget 방법론에 의한 한국의 식품첨가물 사용기준평가 및 식품첨가물 9종에 대한 이론적 최대섭취량의 추정)

  • 윤혜정;이미경;이창희;이종옥;이철원
    • Journal of Food Hygiene and Safety
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    • v.14 no.2
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    • pp.186-194
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    • 1999
  • The Budget method used currently in Codex for estimation of use levels of food additives was investigated and the specific approach that can be applicable for Koreans has been proposed. Theoretical maximum daily intakes(TMDIs) of benzoate, $\rho$-hydroxybenzoic acid ester, butylated hydroxyanisole(BHA), butylated hydroxytoluene (BHT), t-butylhydroquinone(TBHQ), nitrite, nitrate, sorbate, and sulfite were estimated and compared with corresponding acceptable daily intakes(ADIs). Additives requiring further precise evaluation were screened. TMDIs of benzoate, BHA, BHT, TBHQ, nitrite, and sulfite exceeded ADIs. On the other hand, it is appeared that TMDIs of $\rho$-hydroxybenzoic acid ester, nitrate, and sorbate were below ADIs. It is expected that the Budget method may be used as one approach for the estimation of use level and risk assessment.

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Preparation of Ampholyte Grafted Hollow-fiber Membrane and Its Adsorption Characteristic on Metallic Ions (양성전해질 고정막의 제조 및 그것의 금속이온 흡착 특성)

  • Choi, Hyuk-Jun;Park, Sang-Jin;Kim, Min
    • Membrane Journal
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    • v.20 no.2
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    • pp.151-158
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    • 2010
  • This paper presents the synthesis of ampholyte immobilized hollow-fiber membranes and adsorption characteristic of metallic ions. This is prepared by radiation induced grafting polymerization of an epoxy group containing Glycidyl methacrylate (GMA) onto an existing polyethylene porous hollow-fiber membrane. Ampholyte ion-exchanged alkalic group, $-NH_2$ (amine function) of Taurine (TAU) is reacted with glycidyl of GMA for the synthesis of stable membrane. However, Sodium sulfite (SS) membrane is also prepared by making chemical bonds with GMA of porous hollow-fiber membrane for the comparison of adsorption characteristic of metallic ions. These are called as TAU and SS membranes, respectively. It is shown that TAU membrane shows a steady flux, 0.9 m/h regardless of the density of TAU, while the flux of SS membrane decreases rapidly as the density of $SO_3H$ group increases. SS membrane showed a negligible flux. TAU membrane with the density 0.8 mmol/g shows the amount of metallic ions adsorbed in the following order, Cu > Cd > Mg > Sb > Pb. In general, TAU membrane with high density and reaction time showed the high amount of metallic ions adsorbed and flux.

Effects of Mixed Activators on Enzymatic Activation for Wool.polyester Blend Fabrics (양모.폴리에스터 혼방직물의 효소가공 시 활성제 복합사용의 효과)

  • Song, Hyun-Joo;Song, Wha-Soon
    • Journal of the Korean Society of Clothing and Textiles
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    • v.32 no.9
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    • pp.1461-1466
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    • 2008
  • This study provides effects of mixed activators on enzymatic activation and determines optimum mixture ratio for enzymatic treatment. Wool 80% and polyester 20% blend fabric and papain from carica papaya are used in this experiment. L-cysteine and sodium sulfite are used as activators for papain treatment process. The treatment condition is pH 7.5, $70^{\circ}$, papain concentration 10%(o.w.f), 60 minutes. L-cysteine and sodium sulfite are added in enzyme solution with various concentrations($0{\sim}50mM$). The optimum treatment condition is determined by measuring weight loss, tensile strength, whiteness, water contact angle(WCA), dyeability and surface micrographs. The results are as follow; The optimum mixture ratio of activators is L-cysteine 2mM and sodium sulfite 10mM. Mixed activators assists in improving the activation of papain. WCA of papain treated fabrics is decreased since papain treatment with activator mixture makes wool polyester blend fabrics more hydrophilic. Dyeing property of papain-treated fabrics more improves by the treatment with mixed activators than with single activator. It means that this method can save time and lower cost. After papain treatment in the presence of mixed activator, the surface of fabrics is modified. The surface of wool fiber shows to be descaled and hydrolyzed, and that of polyester fiber shows to be cracked.

Effect of addition of Tl+ and Pd2+ on the texture and hardness of the non-cyanide gold plating layer (논시안 금도금층의 조직과 경도에 미치는 Tl+ 과 Pd2+ 이온첨가의 영향)

  • Heo, Wonyoung;Son, Injoon
    • Journal of the Korean institute of surface engineering
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    • v.55 no.6
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    • pp.460-468
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    • 2022
  • Due to its high electrical conductivity, low contact resistance, good weldability and high corrosion resi-stance, gold is widely used in electronic components such as connectors and printed circuit boards (PCB). Gold ion salts currently used in gold plating are largely cyan-based salts and non-cyanic salts. The cya-nide bath can be used for both high and low hardness, but the non-cyanide bath can be used for low hardness plating. Potassium gold cyanide (KAu(CN)2) as a cyanide type and sodium gold sulfite (Na3[Au(SO)3]2) salt as a non-cyanide type are most widely used. Although the cyan bath has excellent performance in plating, potassium gold cyanide (KAu(CN)2) used in the cyan bath is classified as a poison and a toxic substance and has strong toxicity, which tends to damage the positive photoresist film and make it difficult to form a straight side-wall. There is a need to supplement this. Therefore, it is intended to supplement this with an eco-friendly process using sodium sulfite sodium salt that does not contain cyan. Therefore, the main goal is to form a gold plating layer with a controllable hardness using a non-cyanide gold plating solution. In this study, the composition of a non-cyanide gold plating solution that maintains hardness even after annealing is generated through gold-palladium alloying by adding thallium, a crystal regulator among electrolysis factors affecting the structure and hardness, and changes in plating layer structure and crystallinity before and after annealing the correlation with the hardness.

The Evaluation of Artificial Lung Using Blood Substitutes (대체혈액을 이용한 인공폐의 평가에 관한 연구)

  • Kim K.B.;Hong S C.;Kim M.H.;Jheong G.R.;Lee S.C.
    • Journal of Biomedical Engineering Research
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    • v.21 no.3 s.61
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    • pp.311-320
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    • 2000
  • In this paper a newly designed oxygenator module was used to perform the experiments for pressure drop and oxygen transport in order to evaluate the efficiency of the artificial lung. Also, distilled water. sodium sulfite solutions used in this experiment were evaluated for the performance of other artificial lungs. Substituted bloods have many advantages over whole blood in studying pressure drop and oxygen uptake. They are relatively inexpensive, and require fewer variables to be controlled. Furthermore, deoxygenation is not necessary when those solutions are used. In addition to these advantages. assays and interpretation of the experimental results are relatively easy. In the case of using the sodium sulfite solution having the same oxygen partial pressure as whole blood. the oxygen transfer rate of the sodium sulfite solution was basically same as that of whole blood. It was concluded in evaluating the function of artificial lungs that the sodium sulfite solution was suited for measuring oxygen transfer rate. In our module, artificial blood was flowed into the outside of hollow fiber membrane. The artificial lung created in this experiment showed that pressure drop was reduced to $1/3\~1/6$ of that compared to the inside-flow case.

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Effect of Electrochemical Redox Reaction on Growth and Metabolism of Saccharomyces cerevisiae as an Environmental Factor

  • Na, Byung-Kwan;Hwang, Tae-Sik;Lee, Sung-Hun;Ahn, Dae-Hee;Park, Doo-Hyun
    • Journal of Microbiology and Biotechnology
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    • v.17 no.3
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    • pp.445-453
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    • 2007
  • The effect of an electrochemically generated oxidation-reduction potential and electric pulse on ethanol production and growth of Saccharomyces cerevisiae ATCC 26603 was experimented and compared with effects of electron mediators (neutral red, benzyl viologen, and thionine), chemical oxidants (hydrogen peroxide and hypochlorite), chemical reductants (sulfite and nitrite), oxygen, and hydrogen. The oxidation (anodic) and reduction (cathodic) potential and electric pulse activated ethanol production and growth, and changed the total soluble protein pattern of the test strain. Neutral red electrochemically reduced activated ethanol production and growth of the test strain, but benzyl viologen and thionine did not. Nitrite inhibited ethanol production but did not influence growth of the test strain. Hydrogen peroxide, hypochlorite, and sulfite did not influence ethanol production and growth of the test strain. Hydrogen and oxygen also did not influence the growth and ethanol production. It shows that the test strain may perceive electrochemically generated oxidation-reduction potential and electric pulse as an environmental factor.

Chemical Changes of Dissolved Sulfur Dioxide In Vitro (In Vitro에서 $SO_2$ 수용액의 화학적 변화)

  • Lee, Mie-Soon;Lee, Su-Rae
    • Applied Biological Chemistry
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    • v.19 no.1
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    • pp.51-56
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    • 1976
  • Chemical changes of dissolved $SO_2$ were followed in vitro system. Varying concentrations of sulfite solution reached similar Eh values 20 hours after preparation. No further increase of Eh values occurred in acidic solutions. Eh values were more greatly increased in neutral solutions than in alkaline solutions, and slightly higher in light than in dark. The decrease of measurable $SO_2$ content tended to be greater with increasing concentrations of sulfite, on exposure to light, and at higher pH values. A larger amount of hydrogen atoms was produced with higher concentrations of $SO_2$ and in neutral to alkaline solutions than in acidic solutions.

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Determination of Sulfite Contents in Medicinal Herbs (생약재에 함유된 이산화황 함유량 조사)

  • 김충모;송병준;나환식
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.29 no.3
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    • pp.375-379
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    • 2000
  • 이산화황 함유량에 대해 한약재를 대상으로 실험하였으며, 한약을 달여서 탕으로 섭취하는 점을 감안하여 한약을 달인 액을 시료로 이산화황 함량을 조사하여 소비자들이 한약을 달여서 섭취하는 과정에 안전성을 검토하고자 실험을 실시하여 다음과 같은 결과를 얻었다. 생약재 중 이산화황 함유량은 국산 14건중 맥문동(16.9 ppm), 백작약(56.0), 산약(67.7)이 검출되었으며, 수입산은 13건 중 금은화(653.4 ppm), 길경(628.9), 반하(37.1), 백부근(11.7), 부자(82.4), 상백피 (82.7), 석창포(98.0), 패모(497.0),에서 이산화황이 검출되었다. 구입 시기 및 장소를 달리하여 구입한 생약재는 시기나 장소가 달라지면서 생약재에 함유된 이산화황 함량이 서로 차이가 있음을 알 수 있었다. 국산과 수임산과의 이산화황 함량 차이를 조사한 결과 국산의 경우에는 천화분 1건(29.5 ppm)을 제외한 나머지 시료에서 불검출을 보였으나, 수입산의 경우 13건중 7건(건지황, 과루인, 지실, 구기자, 남성, 우슬, 천화분)이 검출되어, 수입산이 국산보다 이산화황을 더 많이 함유하고 있는 것으로 나타났다. 약탕기로 한약액을 달여서 검사한 결과 최초 구입한 생약재의 함유량보다 이산화황 함량이 감소하는 경향을 보였으나, 원래 생약에 다량 함유되어 있는 경우에는 최종 잔류되는 함유량도 높게 나타났다.

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