• 한국임상수의학회지
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• 제17권2호
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• pp.411-415
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• 2000

For comparison with conventional barium-gastrointestinal study, modified method using barium and methylcellulose was performed in 16 normal dogs (4-8 kg) divided into two groups. The group 1 received 8ml/kg of 40% w/v barium suspension only, and group 2 had taken 15 ml/kg of 0.6% w/v methylcellulose after administration 4 ml/kg of 40% w/v barium suspension by feeding tube. The barium suspension was prepared mixing full strength-barium suspension with water and methylcellulose solution was produced by blending methylcellulose sterilized water Sequential radiographs, lateral and ventrodorsal projections were obtained at 5 minute, 20 minute,40 minute. 60 minute and every 30 minutes thereafter, until the contrast is seen in the large intestine Inage qual- ity was rated by three veterinary radiologists as " poor" " fair ". "good", or "excellent" We analyzed the relationship between image quality,, transit time. Between two techniques, the modified method with 4ml of 40% w/v barium suspension and 15 ml of 0.6% w/v methylcellulose showed much better image quality ["excellent" result in 7 of the 8 subjects (88%)] and shorter transit time (107 minutes) toe the cecum. In addition, the best image quality was obtained at 20 and 40 minutes after admin-istration of contrast agent. It call be concluded the modified gastrointestinal study using methylcel-lulose after administration of barium suspension was a simple technique and easily improved the image quality and diagnostic accuracy of gstrointestinal disorders in small animal.racy of gstrointestinal disorders in small animal.

• 한국방사선학회논문지
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• 제14권5호
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• pp.627-634
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• 2020

본 연구는 기존의 납을 대신해 친환경 물질인 황산바륨과 3D 프린터 소재인 PLA 필라멘트를 혼합하여 형태학적 구현을 위한 차폐체를 개발하고자 하였다. 환경 물질인 황산바륨 분말 가루와 3D프린터 소재인 PLA 필라멘트를 사용하였으며, 황산바륨 분말 가루와 PLA를 혼합하기 위하여 압출기로 융합 후 3D 프린터로 차폐체를 제작하였다. 황산바륨 파우더 분말 가루와 PLA 필라멘트 혼합비율을 확인하기 위해 혼합입도를 분석하였으며, 혼합된 차폐체의 차폐능을 확인하기 위해 황산바륨 함유량에 따른 두께별 흡수선량을 구하여 선량을 평가한 후 차폐능을 분석했다.황산바륨 분말 입자와 PLA 필라멘트 혼합 입도 평가 시 외관상과 주사전자현미경 관찰사진에서 함유량이 30%일 때 가장 적정비율로 혼합된 것을 확인하였다. 황산바륨 함유량에 따른 두께별 흡수선량 결과에서 함유량이 0%일 때와 각 % 별 함유량을 비교했을 때 두께 0.5 cm에서 흡수선량의 차이가 가장 크게 나타났으며, 바륨함유량이 30%일 때 두께 3 cm에서 가장 낮은 선량값을 나타냈다. 또한 바륨함유량이 30%를 기점으로 함유량이 증가할수록 흡수 선량값은 다시 높아지는 결과가 나타났다. 기존의 납 대신 친환경 물질인 황산바륨을 필라멘트 소재인 PLA와 혼합하여 형태학적인 차폐체를 만들 수 있었다. 혼합물에 대한 바륨의 혼합비율은 30%가 가장 적절하며, 본 연구를 토대로 진단 방사선 분야 내 3D 프린터를 이용한 형태학적 차폐체 구현을 위한 기초 자료로 사용될 것으로 기대한다.

• 분석과학
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• 제12권3호
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• pp.230-234
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• 1999

$Ba^{2+}$ 및 $Ti^{4+}$이 함유된 염산용액에서 dimethyl oxalate(DMO)가 열분해되면 barium titanyl oxalate(BTO)가 균일 생성되었다. 일정량의 hydroxy propyl cellulose(HPC)를 분산제로 사용하였고 120min의 숙성시간에서 생성된 BTO의 전 침전물을 회수하였다. 반응온도, 염화이온의 농도, $[DMO]_0/([Ba^{2+}]_0+[Ti^{4+}]_0)$의 초기 농도비, 그리고 가한 HPC가 BTO입자의 형태, 화학적 회수율, 그리고 그들의 선구물질로부터 형성된 티탄산 바륨의 특성에 영향을 미침을 알았다.

• 한국결정성장학회지
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• 제6권4호
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• pp.501-508
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• 1996

NaCl-KCl 용융염을 사용하여 strontium barium niobate 분말을 합성하였으며 반응온도, 시간 및 용융염의 첨가량 변화에 따른 반응과정 및 입자 형상 변화를 조사하였다. 반응 온도 및 반응 시간이 증가함에 따라 반응율은 증가하였으며, 분말의 형상은 덩어리 형태에서 침상형태로 변화하였다. 용융염의 첨가량 증가에 따라 반응율은 크게 증가하였으나, 분말의 형상은 침상형태에서 구상형태로 변화하였다. NaCl-KCl 용융염을 사용한 합성법에 의해 융제비가 1인 경우 $1000^{\circ}C$에서, 융제비가 4인 경우 $650^{\circ}C$에서 반응율 90 % 이상의 strontium barium niobate 분말 합성이 가능하였다.

• 한국세라믹학회지
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• 제38권5호
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• pp.401-404
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• 2001

Barium ferrite powders were synthesized by the coprecipitation method using iron-pickling waste acid (IPWA) and BaCl$_2$$.$2H$_2$O as raw materials. Fe$\^$2+/ ions in the IPWA, which contains both Fe$\^$2+/ and Fe$\^$3+/ ions, were oxidized into Fe$\^$3+/ ions using H$_2$O$_2$. Proper amount of BaCl$_2$$.$2H$_2$O was dissolved into the oxidized IPWA. Using NaOH, Ba$\^$2+/ and Fe$\^$3+/ ions were coprecipitated as Ba(OH)$_2$and Fe(OH)$_3$. The coprecipitated Ba(OH)$_2$and Fe(OH)$_3$were washed and dried. Barium ferrite powders were obtained by calcining the dried Ba(OH)$_2$and Fe(OH)$_3$mixture from 400$\^{C}$ to 1000$\^{C}$ with a 100$\^{C}$ interval. Barium ferrite powders were characterized by X-ray diffraction, SEM, and VSM. It was found that barium ferrite powders could be synthesized at around 630$\^{C}$. The synthesized barium ferrite powders showed hexagonal plate shapes with a fairly uniform size. The barium ferrite powder calcined at 900$\^{C}$ showed good magnetic properties, saturation magnetization of 67emu/g and maximum coercivity of 5000 Oe.

• 대한화학회지
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• 제33권1호
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• pp.65-69
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• 1989

방사성 바륨 또는 방사성 란탄 추적자를 함유하고 있는 Ba(NO$_3)_2$ 와 TiO(NO$-3)_2$의 무기혼합용액을 옥살산의 에탄올 용액으로 적정하므로써 바륨티탄닐의 옥살산 염을 합성하였고, 이를 1000$^{\circ}$C에서 하소시켜 BaTiO$_3$를 만들었다. 옥살산염의 분석결과는 BaTiO(C$_2O_4)_2{\cdot}4H_2O$이며, 무기혼합용액중 Ba/Ti의 몰비가 0.950∼1.05 범위 내에서 화학양론적 결합으로 합성됨을 방사성 바륨 추적자의 도움으로 쉽게 확인하였고, Perovskite형의 구조임을 XRD로 확인하였다. 그리고 란탄 첨가제가 침전에 화학적으로 균일하게 혼입됨은 방사성 란탄의 추적자 실험으로 발견하였다. 이와 같은 실험적 사실로부터 침전물의 구성 성분의 결합이 분자준위에서 일어나고 또 티탄산바륨이 단일상의 결정임을 설명하였다.

• The Journal of Advanced Prosthodontics
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• 제14권5호
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• pp.315-323
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• 2022

PURPOSE. The purpose of this study was to investigate the effect of barium silicate filler contents on mechanical properties of resin nanoceramics (RNCs) for additive manufacturing (AM). MATERIALS AND METHODS. Additively manufactured RNC specimens were divided into 4 groups depending on the content of ceramic fillers and polymers: 0% barium silicate and 100% polymer (B0/P10, control group); 50% barium silicate and 50% polymer (B5/P5); 60% barium silicate and 40% polymer (B6/P4); 67% barium silicate and 33% polymer (B6.7/P3.3). The compressive strength (n = 15) and fracture toughness (n = 12) of the specimens were measured, and scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) analyses were performed. Independent sample Kruskal-Wallis tests were performed on the compressive strength and fracture toughness test results, and the significance of each group was analyzed at the 95% confidence interval through post-tests using the Bonferroni's method. RESULTS. B6/P4 and B6.7/P3.3 exhibited much higher yield strength than B0/P10 and B5/P5 (P < .05). Compared to the control group (B0/P10), the other three groups exhibited higher ultimate strength (P < .05). The fracture toughness of B6/P4 and B6.7/P3.3 were similar (P > .05). The content of barium silicate and fracture toughness showed a positive correlation coefficient (R = 0.582). SEM and EDS analyses revealed the presence of an oval-shaped ceramic aggregate in B6/P4 specimens, whereas the ceramic filler and polymer substrate were homogeneously mixed in B6.7/P3.3. CONCLUSION. Increasing the ceramic filler content improves the mechanical properties, but it can be accompanied by a decrease in the flowability and the homogeneity of the slurry.

• 대한방사선기술학회지:방사선기술과학
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• 제46권3호
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• pp.187-195
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• 2023

A shield was made by mixing materials such as bismuth(Bi) and barium(Ba) with silicon to evaluate its shielding ability. Bismuth was made into a shield by mixing a bismuth oxide(Bi₂O₃) colloidal solution and a silicon base and applied to a fibrous fabric, and barium was made by mixing lead oxide(PbO) and barium sulfate(BaSO₄) with a silicon curing agent and solidifying it to make a shield. The test was conducted according to the lead equivalent test method for X-ray protective products of the Korean Industrial Standard. The experiment was conducted by increasing the shielding body one by one from the test condition of 60 kVp, 200 mA, 0.1sec and 100 kVp, 200 mA, 0.1 sec. At 60 kVp, 2 lead oxide-barium sulfate shields, 2 bismuth oxide 1.5 mm shields, and 5 bismuth oxide 0.3 mm shields showed shielding ability equal to or higher than that of lead 0.5 mm. At 100 kVp, 2 lead oxide-barium sulfate shields and 2 bismuth oxide 1.5 mm shields showed shielding ability equal to or higher than that of lead 0.5 mm. It was confirmed that when using 2 pieces of lead oxide-barium sulfate and 1.5 mm of bismuth oxide, respectively, it has shielding ability equivalent to that of lead. Bismuth oxide and lead oxide-barium sulfate are lightweight and have excellent shielding ability, thus they have excellent properties to be used as an apron for radiation protection or other shielding materials.

• Journal of Magnetics
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• 제2권1호
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• pp.16-21
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• 1997

Those were investigated, the crystallographic, morphological, and magnetic properties of barium ferrite film (SiO2/Si substrate) prepared by sol-gel dip coating. Appropriate sol was prepared by dissolvin barium and iron nitrate in ethylene glycol at 80$^{\circ}C$. To obtain the films, thermally oxidized p-type silicon substrate with (111) of crystallographic orientation were dipped into the sol, dried at 250$^{\circ}C$ to remove organic material, and heated at 800$^{\circ}C$ for 3 hours in air for the crystallization of barium ferrite. It was found that the particles of barium ferrite formed on the substrate exhibited needle-like shape placing parallel to the substrate and its c-axis is long axis direction. There was tendency that the coercive force in horizontal direction to the substrate was higher than that in vertical direction to it. This tendency was profound in large thickness.

• 한국세라믹학회지
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• 제22권6호
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• pp.9-14
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• 1985

When the barium titanate is Synthesized in Solid-solid reaction the abnormal expansion occurs at about 110$0^{\circ}C$. The mixture was made of corresponding to the theoretical composition of barium titanate. The mixture was fired at various temperature from 90$0^{\circ}C$ to 130$0^{\circ}C$, After that the specimen was tested closely with XDR dilatometer and SEM. The results indicate that 1, The activation energy of barium titanate formation was 42 Kcal/mole. 2, Thermal expansion up to to 90$0^{\circ}C$ was mainly caused by $CO_2$ whereas it was mainly caused by the formation of the secondary phase above 100$0^{\circ}C$. 3. Thermal expansion was not influenced by the forming pressure up to 1000kg/$cm^2$ but it was largely influenced bythe forming pressure above 200kg/$cm^2$.