나노 파우더 제조용 비드밀 제작에 관한 연구

손재엽,남권선,김병희 강원대학교 산업기술연구소 2005 産業技術硏究 Vol.25 No.B

Manufacturing methods of Nano particles can be distinguished by top-down technology as physical method and bottom-up technology as chemical synthetic method. Top-down technology is a kind of method for making microstructure as like carving after forming a macroscopic structure in advance and its typical methods are ball milling, gas condensation method and so on. Nano Particles synthesized by bottom-up method have got to do dispersing process for using them as actual nano particles because their viscosity are very strong and so easy to shape cohesive substances. Therefore, this study is about a particle separating device which separates a certain constant size of grains processed already in mill and mixer because we mostly use media agitating mill as a device of milling and dispersing and we necessarily use very slight balls as media for manufacturing nano particles in the machine. The centrifugal device has been designed for passing and separating below a certain type of grain size after final process of particles in the mill.

THE EFFECT OF PRIMING ETCHED DENTIN WITH SOLVENT ON THE MICROTENSILE BOND STRENGTH OF HYDROPHOBIC DENTIN ADHESIVE

박은숙,배지현,김종순,김재훈,이인복,김창근,손호현,조병훈 대한치과보존학회 2009 Restorative Dentistry & Endodontics Vol.34 No.1

장기적인 상아질 접착의 내구성 악화는 접착층과 혼성층의 친수성 부위에서의 가수분해에 의해 일어나는 것으로 보고 되고 있다. 본 연구의 가설은 콜라겐 망상체를 유기용매로 프라이밍하면 콜라겐 조직을 붕괴시키지 않고 수분을 밀어내고 소수성 단량체와 유기용매로 이루어진 접착제가 침투하여 접착강도를 얻을 수 있다는 것이다. 두 소수성 단량체인 Bisphenol-A-glycidylmethacrylate (Bis-GMA)와 triethyleneglycol dimethacrylate (TEGDMA)를 아세톤, 에탄올 또는 메탄올에 용해시켜 세 가지의 실험용 접착제를 준비하였다. 산 부식과 수세과정 후에, 접착제를 습윤 상아질 표면(습윤 접착)이나 동일한 용매로 프라이밍 된 상아질 표면(용매 프라이밍 접착)에 적용하였다. 48시간 후와 1개월 후, 및 10.000회의 열순환 후에 미세인장결합강도를 측정하였다 접착계면은 주사전자현미경을 이용하여 관찰하였다. 접착방법에 무관하게 대부분의 시편의 접착계면예서 잘 발달된 혼성층을 관찰할 수 있었고 가장 높은 평균 미세인장결합강도는 에탄올을 포함하는 접착제의 48시간 후 시편에서 관찰되었다. 용매를 이용하여 프라이밍하는 접착 방법에서는 에탄올이나 메탄올을 포함하는 접착제에서 열순환 후에 미세인장접착강도가 증가하는 경향을 보였다. 그러나 습윤 접착의 경우에는 시효처리 후 미세인장결합강도의 증가가 관찰되지 않았다. 본 연구에서 에탄올을 이용한 상아질 프라이밍으로 우수한 접착력을 얻을 수 있었고. 열순환 후 접착력이 더욱 증가하였다 Deterioration of long-term dentin adhesion durability is thought to occur by hydrolytic degradation within hydrophilic domains of the adhesive and hybrid layers. This study investigated the hypothesis that priming the collagen network with an organic solvent displacc water without collapse and thereby obtain good bond strength with an adhesive made of hydrophobic monomers and organic solvents. Three experimentaladhesives were prepared by dissolving two hydrophobic monomers bisphenol-A-glycidylmethacrylate (Bis-GMA) and triethyleneglycol dimethacrylate (TEGDMA), into acetone, ethanol or methanol. After an entching and rinsing procedure, the adhesives were applied onto either wet dentin surfaces (wet bonding) or dentin .surfaces primed with the same solvent (solvent-primed bonding). Microtensile bond strength (MTBS) was measured at 48 hrs, 1 month and after 10,000 times of thermocycles. The bonded interfaces were evaluated using a scanning electron microscope (SEM) Regardless of bonding protocols, weIl-developed hybrid layers were observed at the bonded interface in most specimens. The highest mean MTBS was observed in the adhesive containing ethanol at 48 hrs. With solvent-primed bonding increased MTBS tendencies were seen with thermocycling in the adhesives containing ethanol or methanol. However in the case of wet bonding, no increase in MTBS was observed with aging.

2.9% 과산화수소를 함유한 부착형 미백제의 임상적 효능과 안정성에 관한 연구

박은숙,성소래,홍성태,김지은,이소영,황수연,이신재,진보형,손호현,조병훈 大韓齒科保存學會 2006 Restorative Dentistry & Endodontics Vol.31 No.4

2.9%의 과산화수소를 함유한 시험용 부착형 미백제(Medison dental whitening strip, Samsung medical Co.,Anyang,Korea)를 실험군 피험자 23명, 시험용 미백제에서 과산화수소를 제외한 동일한 제재를 대조약으로 대조군 피험자 24명에게 매일 1시간 30분씩, 2주간 적용하여 임상적 효능과 안전성을 평가하였다. 미백 효과는 Shade Vision, Chroma Mete 및 Vitapan classical shade guide를 이용하여 색변화를 측정하여 다음과 같은 결론을 얻었다. 1. 실험군에서의 전체 치아의 색변화량(ΔE^(*))은 세 가지 측정법에서 모두 대조군에 비해 통계적으로 유의한 차이를 보였고 (p < 0.05). 쉽게 인지할 수 있는 정도였다. 2. 색변화는 색좌표 상에서 명도의 증가와 녹색조 및 청색조로의 변화에 의해 얻어졌다. 3. 치아별로는 어두운 견치의 색변화량이 가장 컸고, 측절치, 중절치 순으로 감소하였다. 4. 47명의 피험자 중 5명이 경도의 과민증을 경험하였으나 곧 완화되었다, 치은염증지수와 전기치수검사 결과 시험 전후에 차이가 없어 안전성을 확인하였다. This study evaluated the effectiveness and safety of an experimental bleaching strip (Medison dental whitening strip, Samsung medical Co., Anyang, Korea) containing 2.9% hydrogen peroxide. Twenty-three volunteers used the bleaching strips for one and a half hour daily for 2 weeks. As control group, the same strips in which hydrogen peroxide was not included were used by 24 volunteers with the same protocol. The shade chang (ΔE^(*), color differnce) of twelve anterior teeth was measured using Shade Vision (X-Rite Inc., S. W. Grandville, MI, USA), Chroma Meter (Minota Co., Ltd. Osaka, Japan) and Vitapan classical shade guide (Vita Zahnfabrik, Germany). The shade change of overall teeth in the experimental group was significantly greater than that in the control group (p < 0.05) and was easily perceivable. The change resulted from the increase of lightness (CIE L^(*) value) and the decrease of redness (CIE a^(*) value) and yellowness (CIE b^(*) value). The shade change of individual tooth was greatest in canine, can smallest in central incisor. The safety of the bleaching strip was also confirmed. 〔J Kor Acad Cons Dent 31(4):269-281, 2006〕

Selective Laser Melting of Fe-Ni-Cr Coating on AISI H13 Tool Steel

Byeong don Joo,Jeong Hwan Jang,Jae Hoo Lee,Young Myung Son,Young Hoon Moon 한국표면공학회 2008 한국표면공학회 학술발표회 초록집 Vol.2008 No.-

Assessment of Heavy Metal Concentrations in Greenhouse Soils of Gyeongnam Province

Son, Daniel,Cho, Hyeon-Ji,Heo, Jae-Young,Lee, Byeong-Jeong,Hong, Kwang-Pyo,Lee, Young Han 한국토양비료학회 2017 한국토양비료학회지 Vol.50 No.5

Heavy metal contamination of soil might be a cause of serious concern due to the potential health impacts of consuming contaminated products. In this study, the total content of heavy metals (Cd, Cr, Cu, Ni, Pb, Zn, As, and Hg) in soils was analyzed, and the difference of heavy metal contents depending on crops, soil characteristics, and topography was compared in 169 greenhouse soils obtained from Gyeongnam Province. The concentrations of the heavy metals were $0.25mg\;kg^{-1}$ (ranged 0.01~0.44) for Cd, $28.94(0.53{\sim}72.63)mg\;kg^{-1}$ for Cr, $26.03(0.5{\sim}166.13)mg\;kg^{-1}$ for Cu, $14.91(1.27{\sim}33.22)mg\;kg^{-1}$ for Ni, $15.76(0.43{\sim}57.1)mg\;kg^{-1}$ for Pb, $119.72(6.33{\sim}239.39)mg\;kg^{-1}$ for Zn, $2.54(0.01{\sim}23.57)mg\;kg^{-1}$ for As, and $0.049(0.012{\sim}0.253)mg\;kg^{-1}$ for Hg in topsoils. The concentrations of Pb and As in topsoil were highest in green pepper and those of Cd, Cr, and Ni were highest in melon. In addition, the concentrations of Cr and Ni were highest in diluvial terrace compared with the other topographies. Higher concentrations of Cd, Cr, and Ni were found in silty clay loam and silt loam soils than sandy loam and loam soils.

The Rho-kinase (ROCK) inhibitor Y-27632 protects against excitotoxicity-induced neuronal death in vivo and in vitro.

Jeon, Byeong Tak,Jeong, Eun Ae,Park, Sun-Young,Son, Hyeonwi,Shin, Hyun Joo,Lee, Dong Hoon,Kim, Hyun Joon,Kang, Sang Soo,Cho, Gyeong Jae,Choi, Wan Sung,Roh, Gu Seob Harwood Academic Publishers 2013 Neurotoxicity research Vol.23 No.3

<P>Rho-associated coil kinase (ROCK) inhibitors reportedly prevent neurodegeneration, and abnormal ROCK activation in the central nervous system induces neurite collapse and retraction. However, it is unclear whether the ROCK inhibitor Y-27632 directly protects hippocampal neurons from excitotoxicity. Here, we determined the effects of Y-27632 on neuroprotection following kainic acid (KA)-induced seizures in mice and during glutamate-induced excitotoxicity in HT22 cells. One day after Y-27632 injection, mice were treated with KA and killed 1-2 days later. Fluoro-Jade B and rapid Golgi staining showed that Y-27632 protected against KA-induced neurodegeneration and neurite dystrophy. Y-27632 inhibited increases in hippocampal RhoA and ROCK2 in KA-treated mice as determined by western blot analysis. Immunohistochemical analysis revealed ROCK2-positive neurons and astrocytes in the KA-treated hippocampus. In HT22 cells, Y-27632 also protected neurons and neurite formation during glutamate-induced excitotoxicity in vitro. These results indicate that ROCK inhibition modulates neurite growth and protects neurons from excitotoxicity-induced cell death.</P>

집단미술치료가 보육시설아동의 우울성향 감소에 미치는 영향

강병재(Byeong Jae Kang),손남숙(Nam Sook Son) 한국아동학회 2005 아동학회지 Vol.26 No.2

Before the application of the group art therapy program, children from residential care facilities had higher depression than those from ordinary families. After the application of the program, however, children from residential facilities to whom the program was applied showed significantly lower depression than those in residential care to whom the program was not applied. Still, they showed somewhat higher depression than children living in ordinary families. Nevertheless, children from residential facilities to whom the program was applied showed the largest reduction in depression. Consequently, group art therapy is considered effective in reducing the depression of children in residential care facilities.

Evaluations of the Space Dose and Dose Reductions in Patients and Practitioners by Using the C-arm X-ray Tube Shielding Devices Developed in Our Laboratory

Kim, Jae Seok,Kim, Sung Ho,Lee, Bu Hyung,Kwon, Soo Il,Jung, Hai Jo,Hoe, Seong Wook,Son, Jin Hyun,Kang, Byeong Sam Korean Society of Medical Physics 2016 의학물리 Vol.27 No.4

The present study used a digital angiography x-ray device to measure the space dose and exposure dose of patients and practitioners using x-ray tube shielding devices developed in our laboratory. The intent of the study was to reduce the space dose within the test room, and to reduce the exposure dose of patients and practitioners. The patient and practitioner exposure doses were measured in five configurations in a human body model. The glass dosimeter was placed on the eye lenses, thyroid glands, left shoulder, right shoulder, and gonads. The beam was collimated at full size and at a 48% reduction for a comparative analysis of the measurements. The space dose was measured with an ion chamber at distances of 50 cm, 100 cm, and 150 cm from the x-ray tube under the following conditions: no shielding device; a shielding device made of 3-mm-thick lead (Pb) [Pb 3 mm shield], and a shielding device made of 3-mm-thick Pb (outside) and 3-mm-thick aluminum (Al) (inside) [Pb 3 mm＋Al 3 mm shield]. The absorbed dose was the lowest when the 3-mm-thick Pb＋3-mm-thick Al shield was used. For measurements made with collimated beams with a 48% reduction, the dose was the lowest at $154{\mu}Gy$ when the 3-mm-thick Pb＋3-mm-thick Al shield was used, and was $9{\mu}Gy$ lower than the measurements made with no shielding device. If the space dose can be reduced by 20% in all situations where the C-arm is employed by using the x-ray tube shielding devices developed in our laboratory, this is expected to play an important role in reducing the annual exposure dose for patients, practitioners, and assistants.

차량 및 보행자 데이터베이스설계

반재민(Jae Min Ban),유신(Sheen Lew),민경원(Kyoung Won Min),손행선(Haeng Seon Son),이완주(WanJoo Lee),이병래(Byeong Rae Lee),강현철(HyunChul Kang) 한국통신학회 2012 한국통신학회 학술대회논문집 Vol.2012 No.2

경부고속철도 철도통합무선망(LTE-R)구축 가치향상(VE)에 관한 연구

신재범(Jae Bum Shin),오준호(Jun Ho O),민병균(Byeong Gyun Min),손병두(Byeong Doo Son),김동준(Dong Joon Kim) 한국철도학회 2019 한국철도학회 학술발표대회논문집 Vol.2019 No.5