• Information Display
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• v.4 no.4
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• pp.6-10
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• 2003

우리는 연-X-선 흡수 분광법(soft-X-ray Absorption Spectroscopy ; XAS)을 사용하여 실제 산화물 음극 전자 방출 물질 표면의 화학 구조에 대해 연구하였다. 바륨 3d 흡수단의 고-에너지 분해 스펙트럼은 활성화 과정(온도와 전압 인가) 후에 산화물 음극표면에서 수십 나노미터 깊이 아래까지 바륨 함량이 현저히 증가한다는 것을 보여주었다. 바륨과 산소의 XAS 데이터를 비교해보면 표면에서 과잉 바륨이 형성되는 것을 확실히 입증하고 있다. 게다가 우리는 표면에서의 과잉 바륨의 증가가 활성화 과정에서 열에너지에 의한 것이 아니라 인가된 전압에 의한 것임을 밝혀냈다. 이 결과로 우리는 표면의 과잉 바륨 형성 전체 과정을 규명하고 활성화 동안 표면의 바륨 증가가 분말 입자로부터 니켈 계면으로의 바륨 이온의 전해 이동 속도에 의해 제어된다는 것을 제안한다. 우리는 또한 표면 바륨 증가가 전해 이동에 의한 분말 입자 내의 바륨의 고갈에서 비롯되는 것으로 추정한다.

• Journal of the Korean Society of Radiology
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• v.14 no.5
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• pp.627-634
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• 2020

Instead of lead, we intend to develop shielding materials for morphological implementation by mixing barium sulfate, an eco-friendly substance, and PLA filament, a 3D printer material. The environmental substance, barium sulfate powder and PLA filament, a 3D printer material, were used, and the shielding was made with a 3D printer after being fused into an extruder to mix the powder powder of barium sulfate with PLA. To check the mixing ratio of barium sulfate powder and PLA filament, the mixing input was analyzed, and the absorption dose by thickness according to barium sulfate content was obtained to check the shielding function of the mixed shielding. In the evaluation of the mixture of sulfate barium powder particles and PLA filaments, it was mixed in the most appropriate proportion when the content was 30% in the apparent and electron microscopic observation photographs. In the absorption dose results by thickness according to barium sulfate content, the difference between the content of 0% and the content of each % was greatest at 0.5 cm in thickness and the lowest dose value at 3 cm in thickness when the barium content was 30%. In addition, as the barium content began to increase at 30%, the absorbed dose value increased again. Instead of conventional lead, barium sulfate, an eco-friendly substance, could be mixed with PLA, a filament material, to create morphological shielding. Based on this study, it is expected that the mixing ratio of barium to the mixture is the most appropriate 30%, and will be used as the basis for the implementation of morphological shielding using 3D printers in the diagnosis and treatment section.

• Journal of the Korean Magnetics Society
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• v.2 no.1
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• pp.22-28
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• 1992

Barium ferrite thin films were reactively deposited with Fe and BaO composite targets by a facing tergects sputtering unit. When thermally oxidized silicon wafers were used as substrates, minimum substrate heating of $750^{\circ}C$ was necessary for the perfect c-axis alignment in barium ferrite films. To lower the critical substrate temperature for the good c-axis alignment, such seed layers as ZnO, ${\alpha}-Fe_{2}O_{3}$ and ${\gamma}-Fe_{2}O_{3}$ were tested. The excellent c-axis algnment of BaM was obtained at a substrate temperature of $600^{\circ}C$ on ZnO seed layer whose (002) plane was parallel to the substrate surface. The magnetic properties of the BaM film showed saturation magnetization of 295 emu/cc, perpendicular coercivity of 1.7 kOe and squareness of 0.75. Optimum deposition rate of $230\;{\AA}/min$ was obtained with the composite target and this was 5 to 20 times higher than those of other investigators with oxide targets.

• Journal of the Microelectronics and Packaging Society
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• v.2 no.1
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• pp.35-48
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• 1995

마이크로회로내에서 티탄산바륨 중 바륨의 일부가 납으로 치환됨에 따른 전기적 특 성의 변화를 확인하기 위하여 MOD(금속유기화합물 분해법)공정에 의 barum 2-ethylhexanoate, barium neodecanoate, lead 2-ethylhexanoate 및 titanium dimethoxy 야 -2-ethylhexanoate 와 같은 MOC(금속 유기화합물) 들을 합성하고 공통 용매에 대한 용해 도를 시험하였다. 그 결과 barium 2-ethylhexanoate 만 p-xylene에 대한 용해도가 낮았으며 그 외의 다른 MOC들은 모두 p-xylene 단일 용매에 매우 잘 용해되었다. 바륨의 일부가 납 으로 치환된 티탄산 납바륨 박막은 MOC 혼합용액을 ITO/glass, Pt/SiO2/Si 및 Pt/Ti/SiO2/Si 웨이퍼 기판 위에 spin coating 하고 소성하여 얻었다. 이와 같이 얻어진 박막 의 전기적 특성을 측정하고 그 결과를 비교 고찰하였다.

• Korean Journal of Materials Research
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• v.7 no.5
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• pp.423-430
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• 1997

졸-겔 dip coating법에 의해 제조한 바륨페라이트 박막의 미세구조와 결정학적인 구조 특성에 관해 조사하였다. 기판에 형성된 바륨페라이트 입자는 침상 형태의 입자들로 구성되어 있었으며, C축은 장축 방향이었고, 막 두께가 증가함에 따라 침상형 입자들은 기판에 평행하게 배향하는 경향을 나타내었다. 박막은 바륨페라이트층, Ba, Fe, SiO$_{2}$로 구성되어 있는 중간층, 그리고 기판층인 SiO$_{2}$층으로 구성되어 있었으며, 중간층과 SiO$_{2}$층간의 계면은 Ba 와 SiO$_{2}$간의 화합물로 구성되어 있었다. 침상 형태의 입자는 95$0^{\circ}C$에서 3시간 열처리하므로써 완전히 소실하였고, 130$0^{\circ}C$에서 3시간 열처리하므로써 c면이 기판에 평행하게 위치하는 완전한 육각판상 형태의 입자로 변화되었다.

• Journal of the Korean Chemical Society
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• v.33 no.1
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• pp.65-69
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• 1989

Barium titanyl oxalate was synthesized by adding ethanol solution of oxalic acid to the mixed aqueous solution which contained barium or lanthanum radiotracers in addition to Ba(NO$_3)_2$ and TiO(NO$_3)_2$. The oxalate was finally converted to BaTiO$_3$ by calcination at 1000$^{\circ}$C in air. The chemical formula of the oxalate was confirmed to be BaTiO(CTEX>$_2O_4)_2{\cdot}4H_2O$ by the thermal analysis of the barium titanyl oxalate. When the mixture's molar ratio(Ba/Ti) was within a range of 0.950-1.05, the formation of stoichiometric Barium titanate was confirmed with the help of barium tracers. The homogeneity of lanthanum deposite in the final product was also confirmed through the behavior of lanthanum tracers. The results as well as those obtained by XRD and SEM have been explained on the basis of the fact that the reaction occurs on the molecular level in solution and the barium titanate is formed in crystals of single phase.

• Journal of the Korean Ceramic Society
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• v.38 no.2
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• pp.173-178
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• 2001

본 연구에서는 PDP용 녹색 형광체의 대안인 $Ba_{1.3}$A $l_{12}$ $O_{19}$:$Mn^{2+}$ 분말을 초음파 분무 열분해법으로 합성하였으며 활성제인 $Mn^{2+}$의 첨가량과 모체를 구성하는 바륨 및 알루미늄의 전구체 물질들의 조합을 변화시킴으로써 형광체 분말의 형태 및 발광특성을 조절하였다. 최적의 발광 휘도를 나타내는 $Mn^{2+}$의 농도는 0.25몰을 첨가하였을 때이며 녹색 발광 영역인 517nm에서 최대 발광 효율을 나타내었다. 바륨의 전구체 물질로는 초산염, 질산염, 염화물 및 수산화물을 사용하였으며 알루미늄 전구체 물질로는 질산염 및 염화물을 사용하였다. 전구체는 합성된 분말의 형상에 영향을 미치는데 구형을 유지하거나 혹은 뭉치거나 구형이 깨지는 등 전구체 조합에 따라 얻어지는 분말의 형태가 달라졌다. 합성된 형광체 분말들은 일반적인 고상 반응의 온도보다 낮은 열처리 온도인 140$0^{\circ}C$, 5시간 유지에서는 좋은 VUV 발광 특성을 가졌다. 또한 전구체의 조합은 형광체 발광 효율에도 영향을 미치는데 바륨과 알루미늄은 염화물을, 망간은 질산염을 사용하였을 때 가장 좋은 발광 휘도를 나타내었다.다.다.다.

• Journal of radiological science and technology
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• v.34 no.2
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• pp.141-147
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• 2011

We developed an alternative radiation shielding material which is economical and has high protection efficiency. We validated the material in the form of sheet to make an apron. We increased the rate of barium and mixed tourmaline into silicon to improve the flexibility and protection rate of the sheet. The results showed that the shielding effect at low radiation energy is good enough with both 5 mm and 7 mm thickness. In the future, we will perform a quantitative evaluation of the reproducibility, volumetric efficiency, and porosity in mixing the ingredients.

• Journal of the Korean Chemical Society
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• v.25 no.1
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• pp.21-25
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• 1981

A study was made of the influence of butyl alcohol on the distribution coefficients of barium and mercury ions between the ion exchange resin, Dowex 50w-x8, 200~400 mesh and solutions containing hydrochloric acid, butyl alcohol and water. The determination of the distribution coefficients of barium and mercury are made by using the batch method. The distribution coefficients of metal ions decrease generally as the number of branches of carbon in the molecule of butyl alcohol increase. It shows that solubility in water and stereo-isomerism of the butyl alcohol have influence upon the distribution coefficient of barium and mercury.

• Journal of the Korean Society of Radiology
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• v.11 no.5
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• pp.329-334
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• 2017

The purpose of this study is to estimating the possibility of manufacturing radiation shielding sheet by searching for environmentally friendly materials suitable for medical environment of medical radiation shielding. There are many tungsten products which are currently used as shielding materials in place of lead, but there are small problems in the mass production of lightweight shielding sheets due to economical efficiency. To solve these problems, a lightweight, environmentally friendly material with economical efficiency is required. In this study, Barium sulphate and Iodine were proposed. Both materials are already used as contrast medias in radiography, and it is predicted that the shielding effect will be sufficient in a certain region as a shielding material because of the characteristic of absorbing radiation. Therefore, in this study, we used a Monte Carlo simulation to simulate radiation shielding materials. When it is a contrast agent such as Barium sulfate and Iodine, the radiation absorption effect in the high energy region appears greatly, and the effectiveness of the two shielding substance in the energy region of the star with thickness of 120 kVp is also evaluated in the medical radiation imaging region. Simulated estimation results it was possible to estimate the effectiveness of shielding for all two substances. Iodine has higher shielding effect than barium sulfate, 0.05 mm thick appears great effect. Therefore, the Monte Carlo simulation confirms that iodine, which is a radiological contrast agent, is also usable as barium sulfate in the production of radiation shielding sheets.