• Korean Chemical Engineering Research
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• 제58권2호
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• pp.313-318
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• 2020

EGME, GL 및 EG와 물을 용매를 사용하여 Bi₂WO₆ 산화물을 수열합성법으로 성공적으로 합성하였다. 이들 촉매들의 물리적 특성을 XRD, DRS, BET 및 SEM 등으로 분석하였고 제조된 촉매들을 사용하여 가시광선 조사 하에서의 로다민 B의 광분해 반응에서의 활성을 조사하였다. XRD의 분석 결과에 의하면 EGME 및 EG를 용매로 사용한 경우에는 Bi₂WO₆의 결정화가 잘 이루어졌다. 또한, 결정화가 잘 이루어진 Bi₂WO₆는 꽃 모양의 형상을 나타내었다. 180 ℃에서 EGME를 용매로 사용하여 제조된 Bi₂WO₆ 촉매가 가장 높은 광분해 활성을 나타내었으며, EGME에 비해 물의 몰 비가 50% 이상으로 제조한 경우에 높은 광촉매 활성을 보여주었다.

• 공업화학
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• 제28권6호
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• pp.705-713
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• 2017

독창적 물질인 $Bi_2WO_6-GO-TiO_2$ 나노복합체를 쉬운 수열법에 의해 성공적으로 합성하였다. 수열반응을 하는 동안, 그래핀 시트 위에 $Bi_2WO_6$와 $TiO_2$를 도포하였다. 합성한 $Bi_2WO_6-GO-TiO_2$ 복합체형 광촉매는 X-선 회절법(XRD), 주사전자현미경(SEM), 에너지 분산 X-선(EDX) 분석, 투과전자현미경(TEM), 라만분광법, UV-Vis 확산반사 분광법(UV-vis-DRS), 및 X-선 광전자분광기(XPS)에 의하여 특성화하였다. $Bi_2WO_6$ 나노입자는 불규칙한 dark-square block 나노 플페이트 형상을 보였으며, 이산화티탄 나노입자는 퀜텀 도트 사이즈로 그래핀 시트 위 표면을 덮고 있었다. 로다민 비의 분해는 농도감소의 측정과 함께 UV 분광법에 의하여 관찰하였다. 합성된 물질의 광촉매 반응은 Langmuir-Hinshelwood 모델과 띠 이론으로 설명하였다.

• Nuclear Engineering and Technology
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• 제54권1호
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• pp.318-325
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• 2022

In this study, composites containing undoped and barium-doped Bi₂WO₆:Ba²⁺were investigated for their shielding against diagnostic X-ray. At first, Bi₂WO₆ and barium-doped Bi₂WO₆ were synthesized with different weight percentages of barium oxide through a hydrothermal process. The as-synthesized nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and Raman spectroscopy (RS). After that, some shields were generated with undoped and barium-doped Bi₂WO₆:Ba²⁺ nanostructure particles incorporated into polyvinyl chloride (PVC) polymer with different thicknesses and 15% weight of the nanostructure. Finally, the prepared samples were exposed to an X-ray tube at 40, 80, and 120 kV voltages, 10 mAs and, 44.5 cm SID (i.e. the distance from the X-ray beam source to the specimen). Linear and mass attenuation coefficients were also calculated for different samples. The results indicated that, among the samples, the one with 7.5 mmol barium-doped Bi₂WO₆ had the most attenuation at the voltage of 40kV, and the attenuation coefficients would increase with an increase in the amount of barium. The samples with 15 and 17.5 mmol barium-doped Bi₂WO₆ had higher attenuation than the others at 80 and 120 kV. Moreover, the half-value layer (HVL), tenth-value layer (TVL) and 0.25 mm lead equivalent thickness were calculated for all the samples. The lowest HVL value was for the sample with 7.5 mmol barium-doped Bi₂WO₆. As the result clearly show, an increment in the barium-doping content leads to a decrease in both HVL and TVL. In every three voltages, 0.25 mm lead equivalent thickness of the barium-doped composites (7.5 mmol and 15 mmol) had less than the other composites. The lowest value of 0.25 mm lead equivalent thickness was 7.5 barium-doped in 40 kV voltage and 15 mmol barium-doped in 80 kV and 120 kV voltages. These results were obtained only for 15% weight of the nanostructure.

• Bulletin of the Korean Chemical Society
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• 제30권3호
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• pp.630-635
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• 2009

For use as a photocatalyst, bismuth tungsten oxide, $Bi_2WO_6$, was successfully synthesized by hydrothermal treatment at pH = 11 and heating at 200 ${^{\circ}C}$ for 24h, and samples were subsequently thermal treated at 400, 600, and 800 ${^{\circ}C}$ to increase crystallinity. TEM results revealed that the initial untreated particles were sheet‐shaped, grain size was below 80 nm, and it increased with treated temperatures. These $Bi_2WO_6$ samples absorbed at around 400 nm in the visible light range and the intensity of absorption was particularly strongest in samples thermal treated at 600 ${^{\circ}C}$. Their photoluminescence abilities, related to the recombination between the excited electrons and holes, were overall small for other general photocatalysts such as TiO2, and the smallest in the case of thermal treatment at 600 ${^{\circ}C}$, as reversible result of UV‐visible absorbance. Methyl orange of 5.0 ppm aqueous solution was almost completely removed after 2 h when treated over the $Bi_2WO_6$ thermal treated at 600 ${^{\circ}C}$.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2019년도 정기학술대회 발표논문집
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• pp.75-75
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• 2019

• 한국방사선학회논문지
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• 제12권6호
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• pp.713-718
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• 2018

많은 선행 연구에서는 무연 차폐재를 제작하기 위하여 몬테카를로 시뮬레이션을 통해 방사선 차폐 능력과 경량화에 대한 가능성을 제시하고 있다. 하지만, 이는 바인더 및 미세 기공에 대한 구현이 어렵기에 제품화 공정에 필요한 정보를 충분히 제공하지 못하는 실정이다. 이에 본 연구에서는 제품화 공정에 요구되는 겔 페이스트에 대한 정보를 사전에 제공하기 위하여 스크린 프린팅 공법을 활용하여 충전율에 따른 방사선 차폐 능력에 대한 결과를 제시하였다. 본 연구에서는 방사선 차폐 능력을 평가하기 위해 IEC 61331-1: 2014와 KS A 4025에 부합하도록 실험 환경을 설계하였으며, 방사선 조사 조건은 KS A 4021 규격을 준용하여 총 여과 2.0 mmAl로 여과된 100 kVp를 이용하였다. 본 연구 결과, TVL를 기준으로 Pb $1270{\mu}m$, $BaSO_4$ $3035{\mu}m$, $Bi_2O_3$ $1849{\mu}m$, $WO_3$ $2631{\mu}m$에서 근사한 값으로 분석되었다. 또한, 충전율은 $BaSO_4$ 38.6%, $Bi_2O_3$ 27.1%, $WO_3$ 30.15%로 분석되었다. 하지만, 차후 저온고압 성형을 적용한다면 충전율을 높이면서도 기공률을 낮춤으로서 방사선 차폐 능력의 개선이 충분히 가능할 것으로 기대된다.

• 공업화학
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• 제5권3호
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• pp.478-500
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• 1994

융제법을 이용하여 육티탄산칼륨 wisker를 합성하였다. 바람직한 융제를 설정하기 위해 $V_2O_5$, $Bi_2O_3$, $B_2O_3$, $Pb_3O_4$, KCl, $K_4P_2O_7$, $K_2WO_4$ 그리고 $K_2MoO_4$의 8가지 형태의 융제가 조사되었으며 반응온도와 반응시간, $K_2CO_3$에 대한 $TiO_2$의 몰비, $K_2CO_3$와 $TiO_2$의 혼합물에 대한 flux의 몰비, 티탄산칼륨 섬유의 합성을 위한 서냉효과 등의 변수들이 결정화에 미치는 바를 조사하였다. 적절한 융제는 $K_2MoO_4$ 및 $K_2WO_4$였으며 이 두 flux를 사용한 적절한 섬유상 결정화 조건은 반응온도 $1000{\sim}1100^{\circ}C$, 반응시간 5hr, 시료 $K_2CO_3$에 대한 $TiO_2$의 혼합물에 대한 융제의 몰비는 4.0 그리고 $K_2CO_3$에 대한 $TiO_2$의 몰비는 6.0이 가장 바람직하였으며 아울러 서냉조작은 장섬유의 성장에 효과적이었다.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2018년도 정기학술대회 발표논문집
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• pp.78-78
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• 2018

• 혜화의학회지
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• 제9권1호
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• pp.595-646
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• 2000

I. Introduction Bi(痺) means blocking. BiJeung is one kind of symptoms making muscles, bones and jonts feel pain, numbness or edema. For example it can be gout or SLE etc. says that Bi is combination of PungHanSeup. And many doctors said that BiJeung is caused by food, fatigue, sex, stress and change of weather. Therefore we must treat BiJeung by character of patients and characteristic of the disease. Many famous doctors studied medical science by their fathers or teachers. So the history of medical science is long. So I studied ${\ll}Bijeungjujip{\gg}$. II. Final Decision 1. JoGeumTak(趙金鐸) devided BiJeung into Pung, Han, Seup and EumHeo, HeulHeo, YangHeo, GanSinHeo by charcter or reaction of pain. And he use DaeJinGyoTang, GyegiGakYakJiMoTang, SamyoSan, etc. 2. JangPaeGyeu(張沛圭) focused on division of HanYeol(寒熱; coldness and heat) in spite of complexity of BiJeung. He also used insects for treatment. They are very useful for treatment of BiJeung because they can remove EoHyeol(瘀血). 3. SeolMaeng(薛盟) said that the actual cause of BiJeung is Seup. So he thought that BiJeung can be divided into PungSeup, SeupYeol, HanSeup. And he established 6 rules to treat BiJeung and he studied herbs. 4. JangGi(張琪) introduced 10 prescriptions and 10 rules to cure BiJeung. The 1st prescription is for OyeSa, 2nd for internal Yeol, 3rd for old BiJeung, 4th for Soothing muscles, 5th for HanSeup, 6th for regular BiJeung, 7th for functional disorder, 8th for YeolBi, 9th for joint pain and 10th for pain of lower limb. 5. GangSeYoung(江世英) used PungYeongTang(風靈湯) for the treatment of PungBi, OGyeHeukHoTang(烏桂黑虎湯) for HanBi, BangGiMokGwaTang(防己木瓜湯) for SeupBi, YeolBiTang(熱痺湯) for YeolBi, WoDaeRyeokTang(牛大力湯) for GiHei, HyeolPungGeunTang(血楓根湯) for HyeolHeo, ToJiRyongTang(土地龍湯) for the acute stage of SeupBi, OJoRyongTang(五爪龍湯) for the chronic stage of SeupBi, and so on. 6. ShiGeumMook(施今墨) devided BiJeung into four types. They are PungSeupYeol, PungHanSeup, GiHyeolSil(氣血實) and GiHyeolHeo(氣血虛). And he introduced the eight rules of the treatment(SanPun(散風), ChukHan(逐寒), GeoSeuP(, CheongYeol(淸熱), TongRak(通絡), HwalHyeol(活血), HaengGi(行氣), BoHeo(補虛)). 7. WangYiYou(王李儒) explained the acute athritis and said that it can be applicable to HaneBi(行痺). And he used GyeJiJakYakJiMoTang(桂枝芍蘂知母湯) for HanBi and YeolBiJinTongTang(熱痺鎭痛湯) for YeolBi. 8. JangJinYeo(章眞如) said that YeolBi is more common than HanBi. The sympthoms of YeolBi are severe pain, fever, dried tongue, insomnia, etc. And he devided YeolBi into SilYeol and HeoYeol. In case of SilYeol, he used GyeoJiTangHapBaekHoTang(桂枝湯合白虎湯) and in case of HeoYeol he used JaEumYangAekTang(滋陰養液湯). 9. SaHaeJu(謝海洲) introduced three important rules of treatment and four appropriate rules of treatment of BiJeung. 10. YouDoJu(劉渡舟) said that YeolBi is more common than HanBi. He used GaGamMokBanGiTang(加減木防已湯) for YeolBi, GyeJiJakYakJiMoTang or GyeJiBuJaTang(桂枝附子湯) for HanBi and WooHwangHwan(牛黃丸) for the joint pain. 11. GangYiSon(江爾遜) focused on the internal cause. The most important internal cause is JeongGiHeo(正氣虛). So he tried to treat BiJeung by means of balance of Gi and Hyeol. So he ususlly used ODuTang(烏頭湯) and SamHwangTang(三黃湯) for YeolBi, OJeokSan(五積散) for HanBi, SamBiTang(三痺湯) for the chronic BiJeung. 12. HoGeonHwa(胡建華) said that to distinguish YeolBi from Hanbi is very difficult. So he used GyeJiJakYakJiMoTang in case of mixture of HanBi and YeoBi. 13. PiBokGo(畢福高) said that the most common BiJeung is HanBi. He usually used acupuncture with medicine. He followed the theory of EumYongHwa(嚴用和)-he focused on SeonBoHuSa(先補後瀉). 14. ChoiMunBin(崔文彬) used GeoPungHwalHyeolTang(祛風活血湯) for HanBi, SanHanTongRakTang(散寒通絡湯) for TongBi(痛痺), LiSeupHwaRakTang(利濕和絡湯) for ChakBi(着痺), CheongYeolTongGyeolChukBiTang(淸熱通經逐痺湯) for YeolBi(熱痺) and GeoPungHwalHyeolTang(祛風活血湯) for PiBi(皮痺). 15. YouleokSeon(劉赤選) introduced the common principle for the treatment of BiJeung. He used HaePuneDeungTang(海風藤湯) for HaengBi(行痺), SinChakTang(腎着湯), DokHwalGiSaengTang(獨活寄生湯) for TongBi(痛痺), TongPungBang(痛風方) for ChakBi(着痺) and SangGiYiMiTangGaYeongYangGakTang(桑枝苡米湯加羚羊角骨) for YeolBi(熱痺). 16. LimHakHwa(林鶴和) said about TanTan(movement disorders or numbness) and devided TanTan into the acute stage and the chronic stage. He used acupuncture at the meridian spot like YeolGyeol(列缺), HapGok(合谷), etc. And he also used MaHwangBuJaSeSinTang(麻黃附子細辛湯) in case of the acute stage. In the chronic stage he used BangPungTang(防風湯). 17. JinBaekGeun(陳伯勤) liked to use three rules(HwaHyeol(活血), ChiDam(治痰), BoSin(補腎)) to treat BiJeung. He used JinTongSan(鎭痛散) for the purpose of HwalHyeol(活血), SoHwalRakDan(小活絡丹) for ChiDam(治痰) and DokHwalGiSaengTang(獨活寄生湯) for BoSin(補腎). 18. YimGyeHak(任繼學) focused on YangHyeolJoGi(養血調氣) if the stage of BiJeung is chronic. And in the chronic stage he insisted on not using GalHwal(羌活), DokHwal(獨活) and BangPung(防風).

• 한국재료학회지
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• 제9권7호
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• pp.753-759
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• 1999

0.5~4.0mol% 범위의 W $O_3$가 첨가된 ZNR의 미세구조 및 전기적 특성이 조사되어졌다. W $O_3$의 대부분은 입제 교차점으로 편석하여 W 과다상을 형성하였으며, 입계 교차점에는 W 과다상(W $O_3$), Bi 과다상(B $i_2$ $O_3$), 스피넬상(Z $n_{2.33}$S $b_{0.67}$ $O_4$) 등 3상이 공존하였다. W $O_3$첨가량이 증가함에 따라 평균 결정입 크기는 15.5~29.9$\mu\textrm{m}$ 범위로 감소하였으며, W $O_3$는 결정입 성장의 촉진제로 작용하였다. W $O_3$ 첨가량이 증가함에 따라 바리스터 전압과 비직선 지수는 각각 186.82~35.87V/mm, 20.90~3.34 범위로 감소하였고, 누설전류는 22.39 ~ 83.01 $\mu\textrm{A}$ 범위로 증가하였다. W $O_3$ 첨가량이 증가함에 따라 장벽높이와 계면상태밀도는 각각 1.93~0.43eV, (4.38~1.22)$\times$$10^{12}$ $\textrm{cm}^2$ 범위로 감소하였으며, 도너 농도는 (1.06~0.38)$\times$$10^{18}$ /㎤ 범위로 감소함에 따라 W $O_3$는 억셉터 첨가제로 작용하였다.다.다.