• 제목/요약/키워드: Antimony

검색결과 227건 처리시간 0.03초

안티몬 차폐시트의 감마선 차폐 성능평가 (Performance Evaluation of Gamma ray Shielding of Antimony Shielding Sheet)

  • 한상현
    • 대한방사선기술학회지:방사선기술과학
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    • 제41권2호
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    • pp.135-140
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    • 2018
  • In this study, the dose of antimony shielding sheet was measured and the shielding rates according to the distance between the radioisotopes and the detector was analyzed according to the type of $^{99m}Tc$, $^{18}F$, $^{201}Tl$, $^{131}I$, $^{123}I$ using the antimony shielding sheet. The detector was used with an inspector. Six sheets of 0.25 mmPb were prepared with 20 cm width and length. Measurement results using $^{99m}Tc$, $^{201}Tl$, and $^{123}I$ showed that as the thickness of the sheet became thicker, the farther the distance from the source to the sheet was, the smaller the transmitted dose amount was measured. It was analyzed that a thickness of 1.50 mm or more was required to obtain a shielding rates of 90% or more. In the experiments of $^{18}F$ and $^{131}I$, the dose value was highest when 0.25 mm sheet was used, and the shielding rates was negative, unlike the results of other radioisotopes. Since $^{201}Tl$ are used when using antimony sheet and $^{18}F$ and $^{131}I$ have no shielding effect, it is thought that it is effective to reduce dose by repeating training and simulation training so that work can be done in a short time.

AZ31합금의 크립특성에 미치는 Sb의 영향 (Effect of Sb on the Creep Behavior of AZ31 Alloy)

  • 손근용;티안수구이;김경현
    • 연구논문집
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    • 통권33호
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    • pp.137-145
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    • 2003
  • The effects of antimony addition on the microstructures and creep behavior of AZ31 magnesium alloy have been investigated. Constant load creep tests were carried out at temperatures ranging from $150^{\circ}C$ to $200^{\circ}C$, and an initial stress of 50MPa for AZ31 alloys containing antimony up to 0.84% by weight. Results show that small additions of antimony to AZ31 effectively decreased the creep extension and steady state creep rates. The steady state creep rate of AZ31 was reduced 2.5 times by the addition of 0.84% of antimony. The steady state creep rate of AZ31-0.84Sb alloy was controlled by dislocation climb in which the activation energy for creep was 128 kJ/mole. The microstructure of as-cast AZ31-0.84%Sb alloy showed the presence of $Mg_3Sb_2$ precipitates dispersed throughout the matrix. The main reason for the higher creep resistance in AZ31-Sb alloys is due to the presence $Mg_3Sb_2$, which effectively hindered the movement of dislocations during the elevated temperature creep.

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Kinetic Studies on Bromine-Exchange Reactions of Antimony Tribromide with $\alpha$-Phenyl-n-butyl and $\alpha$-Phenyl-i-butyl Bromides in Nitrobenzene$^\dag$

  • Rhyu, Sok-Hwan;Choi, Sang-Up
    • Bulletin of the Korean Chemical Society
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    • 제8권5호
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    • pp.408-414
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    • 1987
  • The rate of bromine-exchange reaction between antimony tribromide and ${\alpha}-phenyl-n-butyl$ bromide in nitrobenzene has been determined, using antimony tribromide labelled with Br-82. The results indicate that the exchange reaction follows the first-order kinetics with respect to the organic bromide, and either the second- or first-order kinetics with respect to antimony tribromide depending on its concentration. The third-order rate constant obtained was 7.50 ${\times}10^{-2}l^2mol^{-2}s^{-1}$ at 28$^{\circ}$C. Similar study on the bromine-exchange reaction between antimony tribromide and ${\alpha}$-phenyl-i-butyl bromide has also been carried out. The results of the study show the same kinetic orders as the ones observed with $\alpha$-phenyl-n-butyl bromide. The third-order rate constant observed was 2.40 ${\times} 10^{-2} l^2mol^{-2}s^{-1}$ at 28$^{\circ}$C. The activation energy, the enthalpy of activation and the entropy of activation for the two exchange reactions mentioned above have been determined. The reaction mechanisms for the exchange reactions are discussed.

우레아를 이용한 ATO(Antimony doped Tin Oxide)의 특성 연구 (Study of the Feature of Antimony doped Tin Oxide Using Urea)

  • 김진철;안용관;최병현;이미재;백종후;심광보
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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    • pp.361-362
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    • 2005
  • Antimony doped tin oxide(ATO) nano powders have been synthesized by homogeneous precipitation method using $SnCl_4\cdot5H_2O$ for precursor, $SbCl_3$ as doped material and urea. The hydrolysis of urea and conductive mechanism and Heat treatment was performed at the temperature from $500^{\circ}C$ to $700^{\circ}C$ in air. The ATO nano powders are characterized by means of Thermogravimetry differential thermal analyzer (TG-DTA), X-ray diffraction (XRD), Brunauer, Emmett, and Teller adsorption (BET), Scanning electron microscopy (SEM) ATO nano powders with an average size of nm and the highest surface area 129 $m^2g^{-1}$ are obtained.

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DBDPE-$Sb_2O_3$ 중 Sb를 분석하기 위한 가압 산분해 전처리 연구 (A Study on the Acid Digestion Bomb Pretreatment Method of Fire Retardant Chemicals (DBDPE-$Sb_2O_3$) for the Determination of Antimony)

  • 최종금;박제안;박경수;김선태;김영상
    • 분석과학
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    • 제13권6호
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    • pp.731-735
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    • 2000
  • 상용되는 난연제인 DBDPE-$Sb_2O_3$ 중 안티몬을 신속 정확하게 분석하기 위하여 가압 산 분해법을 이용하여 전처리하였다. DBDPE-$Sb_2O_3$ 시료를 가압 산 분해장치 내에서 $H_2SO_4:HCl$(1:2) 혼합산을 가하여 $220^{\circ}C$에서 2시간 동안 분해시킨 후 AAS를 이용하여 Sb를 정량하였다. 그 결과 99.6-99.8%의 회수율과 0.94-1.07%의 변동계수값을 얻었다. 이 전처리 방법을 실제시료에 적용하여 40.3과 36.3%의 Sb 함량을 구할 수 있었다.

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高純度안티몬 中의 不純物 (鐵 및 銅)의 8-Hydroxy-quinoline에 依한 吸光光度定量法 (Spectrophotometric Determination of Impurities such as Iron and Copper in High Purity of Antimony with 8-Hydroxy-quinoline)

  • 박규창
    • 대한화학회지
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    • 제11권4호
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    • pp.132-137
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    • 1967
  • 8-Hydroxy-Quinoline(Qxine)에 依한 高純度 Antimony中 不純物(鐵 및 銅)의 吸光光度 定量法을 檢討하였다. 試料의 黃酸溶液에 안티몬을 Masking하기 위하여 必要한 酒石酸의 影響을 調査한 結果, 0.5M-酒石酸溶液 10ml로서 600mg 까지의 안티몬을 Masking할 수 있었다. pH 範圍는 鐵은 5.0-5.7, 銅은 3.5-4.0이었다. 鐵은 580$m{\mu}$ 에서 吸光度를 測定하면 되나, 銅은 15%苛性소오다溶液으로 逆抽出하고, 남은 鐵을 580$m{\mu}$, 410$m{\mu}$ 에서 測定하여 補正할 必要가 있다. 500mg 안티몬에 對하여 鐵은 150${\mu}g$(0.005~0.03%)까지, 銅은 100${\mu}g$(0.005~0.016%)까지 定量이 可能했다.

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티타늄琺瑯후릿트에 關한 硏究 (Studieson Titanium Enamel Frit)

  • 이종근;한기성
    • 대한화학회지
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    • 제4권1호
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    • pp.18-26
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    • 1957
  • There are two problems to be solved by our efforts in the enamel frit. One is how we can cover the enamel frit thin with complete milk white as possible, and the other is how it can be, made resistant for chemicals than before one. The frit which can solved the two problems just mentioned above is titanium enamel frit. This frit has been developed in America after War Ⅱ, and now the research for concerning antimony frit into titanium frit is under development entirely. In order to develope the enamel industry in Korea, it is urgent problem to convert antimony frit into titanium frit. By the way the titanium frit is emulsified titanium oxide crystal which made through reheating the supersaturated solution of titanium oxide in the basis of glass. Unfortunately, there are many obscure points in active fact or which influence on its composition and characteristics yet. However, this task was tried for the first in Korea. As first step, the test was carried on the reference books, and we can be possible convert antimony frit into titanium frit as a result of this experiment. As a conclusion, for the purpose of developing the enamel industry in Korea, we studied that the research for converting antimony enamel frit which has been used popularly into titanium enamel frit which is more economic and resistant for chemicals. As a result of experiments, the following points concerning with titanium frit have become clearly. 1. It is better when the composition of titanium enamel frit has as following table.Man Duck San Silica 24 An Yang Feldspar 20 Borax 28 Sodium Nitrate 4 Cryolite 7 Calcium Carbonate 3.6∼1 Titanium Oxide 10 Calcium phosphate 0 ∼3.2 Calcium Fluoride 0∼1.8 Antimony Oxide 0∼0.5 2. The amount of $TiO_2$, to be added is $10%\;to\;12{%,\;CaF_2\;is\;under\;1.8%,\;P_2O_5\;is\;under\;1.6%,\;Sb_2O_3\;is\;under\;0.5%$. 3. In the titanium frit, the limit of iron oxide amount to be included is under 0. 5%. 4. Comparing the titanium enamel frit with antimony enamel frit not only the titanium frit can be savely 20.6% in the price of raw materials, but one time of glazing and heating process is omitted in each case, and it is known the titanium frit is more resistant for chemicals than antimony frit.

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Characterization of Sol-Gel Derived Antimony-doped Tin Oxide Thin Films for Transparent Conductive Oxide Application

  • Woo, Dong-Chan;Koo, Chang-Young;Ma, Hong-Chan;Lee, Hee-Young
    • Transactions on Electrical and Electronic Materials
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    • 제13권5호
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    • pp.241-244
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    • 2012
  • Antimony doped tin oxide (ATO) thin films on glass substrate were prepared by the chemical solution deposition (CSD) method, using sol-gel solution synthesized by non-alkoxide precursors and the sol-gel route. The crystallinity and electrical properties of ATO thin films were investigated as a function of the annealing condition (both annealing environments and temperatures), and antimony (Sb) doping concentration. Electrical resistivity, carrier concentration, Hall mobility and optical transmittance of ATO thin films were improved by Sb doping up to 5~8 mol% and annealing in a low vacuum atmosphere, compared to the undoped tin oxide counterpart. 5 mol% Sb doped ATO film annealed at $550^{\circ}C$ in a low vacuum atmosphere showed the highest electrical properties, with electrical resistivity of about $8{\sim}10{\times}10^{-3}{\Omega}{\cdot}cm$, and optical transmittance of ~85% in the visible range. Our research demonstrates the feasibility of low-cost solution-processed transparent conductive oxide thin films, by controlling the appropriate doping concentration and annealing conditions.

As, Sb, Bi, Pb가 조동의 부동태에 미치는 영향 (Effect of Arsenic, Antimony, Bismuth and Lead on Passivation Behavior of Copper Anode)

  • 안승천;이상문;김용환;정원섭;정우창
    • 한국표면공학회지
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    • 제39권5호
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    • pp.215-222
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    • 2006
  • The passivity behavior of copper anode containing impurities in copper sulfate solution for electrorefining process was studied at several different levels of impurities such as As, Sb, Bi and Pb. The passivity behavior was investigated by electrochemical techniques (galvanostatic, potentiodynamic and cyclic voltammetry tests) and surface analysis (optical microscopy, electron probe microanalysis, scanning electron microscopy). The results were that arsenic, antimony inhibited passivation and bismuth accelerated it and lead containing anode showed different passivity behavior from above anodes. The improved passivity characteristics could be explained by decrease in oxygen content in passivity film which resulted from a reaction among the impurities, oxygen and copper in the anode. The SEM image revealed that arsenic or antimony containing anode exhibited a porous passivity film and bismuth containing anode showed the compact passivity film and lead containing anode had loose passivity film on anode.

삼염화안티몬과 유기염소화합물 사이의 염소 교환반응에 관한 연구 (A Study on the Chlorine-Exchange Reaction of Antimony Trichloride with Organic Chlorides)

  • 유석환;배영일;최상업
    • 대한화학회지
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    • 제34권1호
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    • pp.19-28
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    • 1990
  • 니트로벤젠 용액 중에서 삼염화안티몬과 염화벤질, 염화-$\alpha$-페닐에틸, 염화디페닐메틸 등의 유기염소화합물 사이의 염소 교환반응에 관한 반응속도론적 연구를 수행하였다. 연구결과 이들 염소교환 반응속도는 삼염화안티몬에 관하여 2차이고 유기염화물에 관하여 1차인 반응속도식을 따르며, Rate = $k_3[SbCl_3]^2$ [Org-Cl] 삼염화안티몬과 유기염화물 사이의 염소 교환반응 속도상수는 유기염화물에 따라 다음과 같은 순서로 증가함을 알았다. 염화벤질 < 염화-$\alpha$-페닐에틸 < 염화디페닐메틸 그리고 이들 염소 교환반응에 관한 메카니즘도 제시하였다.

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