• Korean Journal of Crystallography
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• v.12 no.1
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• pp.1-4
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• 2001

Single crystals of strontium barium metaborate, Sr/sub 1.36/Ba/sub 1.64/(B₃O/sub 6/)₂, were grown for the first time by the high-temperature-solution-growth technique, and a detailed structure analysis was carried out with the space group R3c. The metaborate (B₃O/sub 6/)/sup 3-/ anion planar groups in the title compound form infinite layers parallel to (001) plane, and Sr and Ba atoms are alternatively placed between the layers and are octahedrally coordinated by six O(2) atoms in the neighbouring anion rings.

• Journal of the Korean Ceramic Society
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• v.22 no.4
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• pp.15-20
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• 1985

$(Ba_{0.5} Pb_{0.5})_{1-x} Nd_x TiO_3$ 중의 $_x(Nd$의 양)를 변화시키면서 격자상수와 전기전도도를 측정하였다 c축과 a축의 비(c/a) 의 극대값은 실온에 있어서 전기전도도의 극대값과 일치하였다. 이것은 Nd원자의 치환위치와 강유 전성의 변화에 의한 것으로 고찰되었다 Curie 온도이하에서는 Nd 첨가량의 증가에 따라 전기전도도의 활성화에너지가 증가하는 경향을 나타내었다 이것은 입경의 감소에 따른 Spontaneous polarization의 저하가 원인으로 고찰되었다 첨가량의 역학을 입계의 potential barrier의 높이와 관련지어 논하였다.

• Journal of The Korean Radiological Technologist Association
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• v.28 no.1
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• pp.49-54
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• 2002

Purpose : The objective of the study is to compare and examine the efficacies of barium enema and air reduction as infantile intussusception treatment. Objects and Methods: A retrospective research was conducted on infantile intussusception patients from

• Bulletin of the Korean Chemical Society
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• v.25 no.12
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• pp.1775-1778
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• 2004

The branch-like, feather-like $BaCrO_4$ nano-superstructures were synthesized with bioactive eggshell membrane as directing and assembly template. Studies on the two products revealed that they formed through the self-assembly of nanoparticles, and that the optical properties of the products were different from $BaCrO_4$ bulk materials.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1998.09a
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• pp.55-63
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• 1998

The growing conditions of barium nitrate Ba(NO3)2 single crystals by aqueous solution method have been studied. Supersaturation of Ba(NO3)2 was 0.7% at 32.0$^{\circ}C$ and about 3% 34.0$^{\circ}C$. The obtained single crystals have three kind of morphology; the tertrahedron, the cube and rarely dodecahedron face. The faces of obtained crystals have been identified by X-ray diffractometer.

• Journal of the Korea Convergence Society
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• v.8 no.2
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• pp.113-120
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• 2017

The purpose of this present study was to evaluate the surface radiation dose reduction and radiograph artifact images in computed tomography (CT) for the manufactured radiation shields by using sea-shells. The radiation convergence shields were made from silicons, sea-shells, barium powders, producted circle types of diameter 50 mm, thickness 3.5 mm for 5 kinds (only silicon shield, only barium shield, mixed sea-shells with silicon shield, mixed barium with silicon shield, mixed sea-shells with barium and silicon shield). Radiation generation and acquisition were used 4-channel multi-detector CT. The results of this study showed that mixed sea-shells with silicon shields could reduce the surface dose of 5.3% without radiograph artifact images. In the future, we will expect the radiation convergence shield as environmentally friendly materials by using the recycling of sea-shells with the advantages of silicon which can make various shapes.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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• v.4 no.1
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• pp.1-16
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• 1998

In order to investigate the effect of Bujaleejungtang, by means of oral medication to rats and mice, to isolated intestine and stomach, and the effect to pyloric ulcer, indomethacin-induced ulcer, secretion of gastric juice, and to transport ability of intestine content were studied as the action to G-I tract. The effect to normal rats and resperpine-treated rats were studied as the action to thermo-regulation. The results were as follows: 1. Bujaleejungtang showed the inhibitory effect on the smooth muscle contraction induced by acethylcholine chloride and barium chloride in the isolated mice ileum. 2. Bujaleejungtang showed inhibitory effect on the contraction induced by acetylcholine chloride and barium chloride in the rat fundus-strip. 3. Inhibitory effect of Bujaleejungtang on pyloric ulcer, indomethacin-induced gastric ulcer in rats was statistical recognized(p<0.05). 4. No inhibitory effect of Bujaleejungtang on gastric juice secretion in Shay rats was recognized. 5. Inhibitory effect of Bujaleejungtang on gastric free acidity and total acidity in Shay rats was recognized only when Bujaleejungtang was medicated in high thickness(2000mg/kg) (p<0.001). 6. Inhibitory effect of Bujaleejungtang on pepsin output in Shay rats was recognized only when Bujaleejungtang was medicated in high thickness(2000mg/kg)(p<0.001). 7. Inhibitory effect of Bujaleejungtang on barium sulfate transport in the small intestine of mice was recognized only when Bujaleejungtang was medicated in high thickness(2000mg/kg)(p<0.05). 8. Inhibitory effect of Bujaleejungtang on barium sulfate transport in the large intestine of mice was recognized(p<0.05). 9. Inhibitory effect of Bujaleejungtang on rectal temperature in normal rats was recognized. 10. Inhibitory effect of Bujaleejungtang on rectal temperature in reserpine-treated rats was recognized only when Bujaleejungtang was medicated in high thickness(2000mg/kg)(p<0.05).

• Journal of the Korean Ceramic Society
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• v.11 no.1
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• pp.29-35
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• 1974

Effect of calcium sulfate and barium sulfate on the formation of portland cement clinker was studied by means of chemical analysis. DTA and X-ray diffraction analysis. In the presence of liquid phase, effect of the additives on the formation of tricalcium silicate was examined according to the reaction, 2CaO.$SiO_3$＋CaO$\longrightarrow$3CaO.$SiO_3$, which is the principal reaction in portland cement clinkerization, and optimum conditions in firing clinker concerning amount of additive, firing time and temperature were determined, and its kinetics was referred to. The experimental results are summerized as follow: (1) Appropriate burning temperature range of cement clinker is more limited as the content of calcium sulfate in clinker is increased. Amount of calcium sulfate, firing time and temperature in proper condition of clinkerization is related to each others. Being added suitable quantity of calcium sulfate, firing temperature of clinker can be lowered about $100^{\circ}C$. (2) When 3-5 mole% of calcium sulfate is added, firing time of 15-30 minutes at about $1380^{\circ}C$ is reasonable, and if the content is over7 mole %, firing for 1 hr. or more at $1350^{\circ}C$ is anticipated to be optimum condition. (3) In the reaction of tricalcium silicate formation, the role of barium sulfate as a mineralizer is similar to that of calcium sulfate, but the optimum firing temperature of cement clinker containing barium sulfate tends to be 20-$30^{\circ}C$ higher than that of clinker containing calcium sulfate. (4) When barium sulfate is used as mineralizer, 2-3 mole % of it to tricalcium silicate is recommended and if it is added more than this amount, free CaO is increased rapidly in clinker and alite formation is inhibited.

• Journal of the Korean Ceramic Society
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• v.32 no.10
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• pp.1169-1177
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• 1995

Barium nitrate and yittrium nitrate were dissolved into distilled water. Titaium hydroxide precipitated from titanium chloride with NH4OH was dissolved into nitric acid. Each aqueous solution was mixed for 12 hr in the composition of Ba1-xYxTiO3 (x=0.1∼0.6) and the concentration of mixed solution was 0.1 mol/ι. The mixed solution was sprayed with an ultrasonic atomizer and carried into an electric furnace which was kept at 900∼1000$^{\circ}C$ and pyrolyzed. Pyrolyzed powders were collected on the glass filter with vacuum pump. Aqueous Mn solutiion was added into the synthesized powders, mixed with ultrasonic vibration and sintered at 1300∼1400$^{\circ}C$. Synthesized powders were characterized with SEM, XRD, DT-TGA, and BET. Microsture and resistivity of sintered body were investigated with SEM and multimeter. The results of this experiment were as follows; 1) Yittrium dooped BaTiO3 powders were synthesized above 950$^{\circ}C$. 2) The average particle sizes of powders from BET specific surface area and SEM were 0.045$\mu\textrm{m}$, 0.046$\mu\textrm{m}$ respectively. The particle size distribution was narrow in the range of 0.1∼1.0$\mu\textrm{m}$ from SEM. 3) Room temperature resistivity and pmax/pmin of 0.4 mol% Y doped specimen which was sintered at 1375$^{\circ}C$ were 102∼3 (Ω$.$cm) and 102∼3 respectively. 4) Room temperature resistivity and pmax/pmin of 0.4 mol% Y and 0.04 at% Mn added specimen which was sintered at 1375$^{\circ}C$ were 102∼3 (Ω$.$cm) and 106∼7 respectively. 5) Grain growth was inhibited with addition of Y2O3 and enhanced in addition of Mn by 0.05 atm%.

• Journal of the Korean Applied Science and Technology
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• v.22 no.4
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• pp.306-314
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• 2005

In this study, spherical $pre-BaTiO_3$ particles are prepared by gelation and aging process in autoclave without catalysts. The (Ba-Ti) gel used as a starting material was prepared by aging mixtures of titanyl acylate with barium acetate aqueous solution([glacial acetic acid (AcOH)]/[titanium isopropoxide (TIP)] 4, [barium acetate]/[TIP] 1) at $45^{\circ}C$ for 48hrs. XRD and SEM results for the (Ba-Ti) gel sample at aging process showed that the gel was formed via aggregation of the fine particles. It seems to be the primary particles of bulk (Ba-Ti) gel amorphous, but the spatial arrangement of barium and titanium in the (Ba-Ti) gel is similar to that in crystalline $BaTiO_3$ particles. From XRD and FT-IR. spectroscopy analysis it was found that the crystal structure of the prepared particles continuously transformed from amorphous to tetragonal as the calcination temperature increased, and crystallized spherical cubic and tetragonal $BaTiO_3$ powder obtained at the very low calcination temperature between $500^{\circ}C$ and $900^{\circ}C$ after 1hrs of heat treatment respectively. According to BET analysis result, final particle have pore structure of ink bottle shape which is produced by aggregation of fine spherical particles with surface area of $280m^2/g$ and average pore size of 130nm.