• 제목/요약/키워드: iodine concentration

검색결과 152건 처리시간 0.028초

$Ca^{2+}$ 존재하에서 비이온성 계면활성제와 요오드와의 상호작용 (The Interaction of Nonionic Surfactant with Iodine in the Presence of $Ca^{2+}$)

  • 박정순;권오윤;백우현
    • 대한화학회지
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    • 제37권1호
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    • pp.36-42
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    • 1993
  • $Ca^{2+}$ 이온 존재하에서 비이온성 계면활성제, $nonylphenol-(ethylene oxide)_n\;[NP-(EO)_n; n = 11, 40, 100]$와 요오드간의 charge transfer (CT) 상호작용을 UV-Visible spectrophotometer를 이용하여 수용액중에서 조사하였다. Spectra의 특성은 $Ca^{2+}$ 이온 농도와 EO 갯수에 의존하였다. CMC 이상에서 $NP-(EO)_{11}$$NP-(EO)_{40}$에 대한 $Ca^{2+}$이온 첨가에 따른 CT band는 증가하다가 다시 감소하였으며, $NP-(EO)_{100}$에 대해서는 계속적인 증가를 보였다. CT band의 강도가 증가하는 것은 $Ca^{2+}$이온 존재하에서 미셀 구조가 더욱 조밀해진데 따른 요오드와의 donor-acceptor overlap 증가로 볼 수 있다. 이러한 현상들은 수용액 중에서 상태적으로 자유로이 여러가지 배향을 가질 수 잇는 선형 ethylene oxide(EO) 사슬이 유사 크라운 에테르 구조를 형성하여 $Ca^{2+}$ 이온과 착물을 형성할 수 있는 가능성을 보여준다.

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전하이동 착물형성에 의한 Ephedrine Alkaloids의 분석화학적 연구 (Spectrophotometric Determination of Ephedrine Alkaloids by Charge-Transfer Complexation)

  • 옥치완;백채선
    • 약학회지
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    • 제31권5호
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    • pp.330-337
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    • 1987
  • The weak UV absorbing ephedrine alkaloids such as ephedrine, pseudoephedrine, methylephedrine and norephedrine could be analyzed by charge-transfer spectrophotometric method. The results obtained are summarized as follows: (1) It was possible to determine a weak UV absorbing ephedrine alkaloids using the intense charge-transfer UV bands in chloroform. (2) This method was suitable for the spectrophotometric determination of ephedrine alkaloids in mixed pharmaceutical preparation. (3) Linear relationship was found between absorbance and concentration in the range of 1.0$\times$$10^{-5}M$~5$\times$$10^{-5}M$ of ephedrine ($\varepsilon$= 2.72$\times$$10^{4}LM^{-1}cm^{-1}$ and pseudoephedrine ($\varepsilon$=2.84$\times$$10^{4]LM^{-1}cm^{-1}$), 1.0$\times$$10^{-5}M$~5$\times$$10^{-5}$M of methylephdrine ($\varepsilon$=1.68$\times$$10^{4}LM^{-1}cm^{-1}$) and 1/3$\times$$10^{-4}M$~4/3$\times$$10^{-4}M$ of norephedrine ($\varepsilon$=0.74$\times$$10^{4}LM^{-1}cm^{-1}$. (4) CT- complex of ephedrine, pseudoephedrine and methylephedrine has absorption maxima at 293nm and norephedrine have absorption maximum at 253nm. (5) CT-complexes were formed in a 1:1 ratio between ephedrine alkaloids and iodine in chloroform. (6) By UV, IR, and $^1H$-NMR spectra, it could be inferred that CT-complexes were formed by interaction between the basic nitrogen of ephedrine alkaloids as electron (n) donor and iodine as electron ($\sigma$) acceptor.

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The strategies for the supplementation of vitamins and trace minerals in pig production: surveying major producers in China

  • Yang, Pan;Wang, Hua Kai;Li, Long Xian;Ma, Yong Xi
    • Animal Bioscience
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    • 제34권8호
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    • pp.1350-1364
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    • 2021
  • Objective: Adequate vitamin and trace mineral intake for pigs are important to achieve satisfactory growth performance. There are no data available on the vitamin and trace mineral intake across pig producers in China. The purpose of this study was to investigate and describe the amount of vitamin and trace minerals used in Chinese pig diets. Methods: A 1-year survey of supplemented vitamin and trace minerals in pig diets was organized in China. A total of 69 producers were invited for the survey, which represents approximately 90% of the pig herd in China. Data were compiled by bodyweight stages to determine descriptive statistics. Nutrients were evaluated for vitamin A, vitamin D, vitamin E, vitamin K, thiamine, riboflavin, vitamin B6, vitamin B12, pantothenic acid, niacin, folic acid, biotin, choline, copper, iron, manganese, zinc, selenium, and iodine. Data were statistically analyzed by functions in Excel. Results: The results indicated variation for supplemented vitamin (vitamin A, vitamin D, vitamin E, vitamin K, vitamin B12, pantothenic acid, niacin, and choline) and trace minerals (copper, manganese, zinc, and iodine) in pig diets, but most vitamins and trace minerals were included at concentrations far above the total dietary requirement estimates reported by the National Research Council and the China's Feeding Standard of Swine. Conclusion: The levels of vitamin and trace mineral used in China's pig industry vary widely. Adding a high concentration for vitamin and trace mineral appears to be common practice in pig diets. This investigation provides a reference for supplementation rates of the vitamins and trace minerals in the China's pig industry.

Mass Interception Fractions and Weathering Half-lives of Iodine-131 and Radiocesium in Leafy Vegetables Observed after the Fukushima Daiichi Nuclear Power Plant Accident

  • Tagami, Keiko;Uchida, Shigeo
    • Journal of Radiation Protection and Research
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    • 제46권4호
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    • pp.178-183
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    • 2021
  • Background: This study was carried out to provide environmental transfer parameter values to estimate activity concentrations of these radionuclides in agricultural crops when direct contamination occurred. Materials and Methods: Mass interception fractions (FBs) and weathering half-lives (Tws) of 131I and radiocesium were calculated using openly available monitoring data obtained after the Fukushima Daiichi Nuclear Power Plant accident. FB is the ratio between the initial radioactivity concentration of a radionuclide retained by the edible part of the plant (Bq·kg-1 fresh weight [FW]) and the amount of deposited radionuclide in that area (Bq·m-2). Tw values can be calculated using activity concentrations of crops decreased with time after the initial contamination. Results and Discussion: Calculated FB and Tw values for 131I and radiocesium were mostly obtained for leafy vegetables. The analytical results showed that there was no difference of FBs between 131I and radiocesium by t-test; geometric mean values for leafy vegetables cultivated under outdoor conditions were 0.058 and 0.12 m2·kg-1 FW, respectively. Geometric mean Tw value of 131I in leafy vegetables grown under outdoor conditions was 8.6 days, and that of radiocesium was 6.6 days; there was no significant difference between Tw values of these radionuclides by Wilcoxon rank sum test. Conclusion: There was no difference between 131I and radiocesium for FBs and Tws. By using these factors, we would be able to carry out a rough estimation of the activity concentrations of 131I and radiocesium in the edible part of leafy crops when a nuclear accident occurred.

Preparation and Characterization of Carbonized Material from Al-Fe-Mg-Si Nanocomposites Impregnated Biomass

  • Kim, Jin Woo;Lee, Chul Jae
    • International Journal of Advanced Culture Technology
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    • 제6권2호
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    • pp.129-136
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    • 2018
  • Our present study, we impregnated Al-Fe-Mg-Si (NFM) nanocomposites having various concentrations 0, 1000, 3000, and 5000 mg/L in biomass in order to make carbonized biomass. We characterized the properties of the impregnated samples through thermogravimetric/differential thermal analysis (TG-DTA), pore distribution, scanning electron microscopy (SEM). The best results were observed for a NFM nanocomposites concentration of 5000 mg/L. After the first heat treatment, carbonization, and activation processes, the fixed carbon ratio and iodine adsorptivity were increased by 21.89% and 368 mg/g, 23.98% and 475 mg/g, 26.40% and 238 mg/g, respectively. The remove rate of malodorous and VOCs were that the sample shows good removal capabilities. From above results, our sample could be used for the removal of noxious and malodorous gases and for the purification of wastewater.

호두 기름의 성분조성과 항알레르기 효과 (Physico-chemical Composition and Anti-Allegic Effects of Walnut Oil)

  • 서영호;김욱희;김경만;황태영;손현숙
    • 동아시아식생활학회지
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    • 제11권3호
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    • pp.204-208
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    • 2001
  • This study was conducted to investigate physicochemical properties and anti-allergic properties of walnut oil. pH, acid value and iodine value of walnut oil were respectively 4.9, 0.8 and 117. Most of general composition of walnut oil was crude fat(99.9%) Vitamin A and E were 0.06 and 10.25mg/100g and the major fatty acids of walnut oil was linoleic acid(62.8%). Total phenolics and antiallergic effects of walnut oil were estimated 27mg% and 62.82% at the concentration of 0.5% ethanol walnut oil. These results suggest that the walnut oil can provide one of the valuable resource for the functional foods.

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레시틴의 첨가 유, 무에 따른 대두유의 수소첨가 반응성과 리놀렌산의 변화 (Changes of Linolenic Acid Content and Reactivity during Partial Hydrogenation of Soybean Oil with and without Lecithin)

  • 권혜순
    • 한국식품과학회지
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    • 제27권1호
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    • pp.41-46
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    • 1995
  • Changes of fatty acid composition and reaction rate were investigated according to reaction condition during partial hydrogenation reaction of soybean oil until its iodine value decreased from 134 to 110. The reaction conditions were varied in the range of from $170^{\circ}C$ to $210^{\circ}C$ of temperature, from 1.3 atm to 4.2 atm of pressure and from 0.005% to 0.1% of nickel concentration as catalyst. Lecithin was added in soybean oil to investigate the change of reaction rate. The result of addition of lecithin showed that reaction rate decreased to from 2 to 6 times in comparison with non-additive system.

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The Prediction Methods of Iodine-129 release rate : Model Development

  • Park, Jin-Beak;Lee, Kun-Jai;Kang, Duck-Won;Shin, Sang-Woon;Park, Kyung-Rok
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1995년도 추계학술발표회논문집(2)
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    • pp.879-884
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    • 1995
  • The results of performance assessment analyses have shown that the long-lived radionuclides such as I-129 control the potential individual dose impact to the public. I-129 is difficult-to-measure(DTM) in low-level waste because it is non-gamma emitting radionuclides and exists at extremely low concentrations in radioactive waste generated by nuclear reactors. In this study, computer modeling technique to predict release rate of I-129 is developed to provide another tools far performance assessment of land disposal facilities and characteristics of radwaste. Model suggested in this study will give conservative values of I-129 release rate far determination of radwaste characteristics. More detailed approach is implemented to account for release conditions of fuel source-nuclides. 1-131 concentration measured from reactor coolant and released fraction from tramp fuel have dominant roles in calculating release rate of I-129 with fuel defect conditions.

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갑상선(甲狀腺) 기능(機能)상태에 따른 혈청(血淸) 갑상선자극(甲狀腺刺戟)홀몬의 변동(變動)에 관(關)한 연구(硏究) (The Changes of Serum TSH in Various States of Thyroid Function)

  • 노흥규
    • 대한핵의학회지
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    • 제9권2호
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    • pp.1-11
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    • 1975
  • The serum concentrations of thyrotropin (TSH) were measured by means of radioimmunoassay, in 98 cases of normal controls, 51 cases of hyperthyroidism, 80 cases of primary hypothyroidism and 4 cases of secondary hypothyroidism to evaluate the diagnostic significance in various functional states of the thyroid. The obtained data were analyzed in correlation with other thyroid function test values in various phases of the functional thyroid diseases. The results were as follows: 1) The serum TSH concentration in normal control group was $<1.3{\sim}8.0{\mu}U/ml$. 2) The measurement of serum TSH was more significant in diagnostic accuracy compared with that of serum $T_4(75.0{\pm}12.2%)$. Free $T_4$ Index ($64.2{\pm}15.2%$), serum $T_3(41.0{\pm}21.0%)\;or\;T_3$ resin uptake ($41.1{\pm}15.8%$) in evaluation of primary hypothyroidism. 3) In case of overt hypothyroidism, the serum TSH and $T_4$ were both abnormal, compatible with the clinical diagnosis, while in case of preclinical or mild hypothyroidism, the serum $T_4(41.2{\pm}23.8%)\;or\;50.0{\pm}25.0%)$ was much less reliable than serum TSH. 4) In the treatment of primary hypothyroidism with desiccated thyroid, the administration of 1 grain of the hormone per day was sufficient to suppress the serum concentration of TSH to normal range. It showed that the measurement of serum TSH concentration was a significant criteria in evaluating the efficiency of the treatment of hypothyroidism. 5) The measurement of serum TSH concentration is a very significant method in the early detection of hypothyroidism induced during or after the treatment of the hyperthyroidism with antithyroid drugs or radioactive Iodine ($^{131}I$).

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IS 프로세스의 HI 분해반응공정을 위한 전해 - 전기투석(EED) HI 농축 (HI concentration by EED for the HI decomposition in IS process)

  • 홍성대;김정근;이상호;최상일;배기광;황갑진
    • 한국수소및신에너지학회논문집
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    • 제17권2호
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    • pp.212-217
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    • 2006
  • An experimental study on Electro-electrodialysis (EED) for IS (Iodine-Sulfur) process which is well known as hydrogen production system was carried out for the HI concentration from HIx (HI: $H_2O$ : $I_2$ = 1 : 5 : 1) solution. The polymer electrolyte membrane and the activated carbon cloth were adopted as a cation exchange membrane and electrode, respectively. In order to evaluate the temperature effect about HI concentration in fixed molar ratio, three case of temperature were selected to $60^{\circ}C$, $90^{\circ}C$ and $120^{\circ}C$. The electro-osmosis coefficient and transport number of proton have been changed from 1.95 to 1.21 (mol/Faraday) and 0.91 to 0.76, respectively as temperature increase from $60^{\circ}C$ to $120^{\circ}C$. It can be realized that the HI mole fraction in final stage of EED experiments already over the quasi-azeotrope composition.