• 한국결정성장학회지
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• 제15권3호
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• pp.99-103
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• 2005

NaCl-KCl을 flux로 사용한 용융염 합성법을 이용하여 $Pb(Sc_{1/2}Ta_{1/2})O_3$, 분말을 제조하였다. $700^{\circ}C$에서 $800^{\circ}C$의 온도범위에서 상형성 및 분말 상태의 변화를 조사하였다. 용융염 합성법으로 $750^{\circ}C$ 2시간 하소하였을 때, 순수한 페로브스카이트 구조를 가진 $Pb(Sc_{1/2}Ta_{1/2})O_3$ 상이 형성되었으며, 평균 입자 크기는 $0.5\{mu}m$ 이하이고 입방체와 유사한 형상을 갖는 분말이 제조되었다. DIA, X-선 회절 분석, 미세구조 변화를 통해 합성된 분말의 특성을 고찰하였다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제31권3호
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• pp.222-228
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• 2009

Objectives: This study is aimed to compare the wound healing processes between conventional scapel wound and Er,Cr:YSGG (Erbium,Chromium, Yttrium, Scandium, Gallium, Garnet) laser wound using experimental animals. Experimental Design: Two types of wounds were made by linear and round incisions using scalpel and Er,Cr:YSGG laser, respectively, on the thigh of Sprague-Dawley rats. Sprague-Dawley rats were serially sacrified as follows: post operative 12, 24, 48 hours, and 3, 7, 14 days. The skin wounds were grossly and microscopically analyzed during the healing period. Result: The Er,Cr:YSGG laser incision showed better wound healing for the linear incision experiment than the scapel incision. Whereas the scapel incision showed better wound healing for the round incision experiment than the Er,Cr:YSGG linear incision. As the Er,Cr:YSGG laser damage in the round incision experiment could be much increased compared with the round incision by scapel. So, the round incisions by the Er,Cr:YSGG laser were resulted in the poor wound healing compared with those by the scapel. Conclusion: The Er,Cr:YSGG laser is more favorable for the fast linear incision, while the scapel is more favorable for the modified round incision.

• 센서학회지
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• 제23권6호
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• pp.420-424
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• 2014

Aluminum-scandium nitride ($Al_{1-x}Sc_xN$) thin films with a TiN buffer layer have been fabricated on SUS430 substrate by RF reactive magnetron sputtering at room temperature under 50% $N_2$/Ar. The effect of Sc-doping on the structure and piezoelectric properties of AlN films has been investigated using SEM, XRD, surface profiler and pressure-voltage measurements. The as-deposited AlN films showed polycrystalline phase, and the Sc-doped AlN film, the peak of AlN (002) plane and the crystallinity became very strong. With Sc-doping, the crystal size of AlN film was grown from ~20 nm to ~100 nm. The output signal voltage of AlN sensor showed a linear behavior between 15~65 mV, and output signal voltage of Sc-doped AlN sensor was increased over 7 times. The pressure-sensing sensitivity of AlN film was calculated about 10.6mV/MPa, and $Al_{0.88}Sc_{0.12}N$ film was calculated about 76 mV/MPa.

• 한국세라믹학회지
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• 제42권9호
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• pp.637-644
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• 2005

In order to find a proper buffering material which can prohibit an unwanted interfacial reaction between anode and electrolyte of LSGM-based SOFC, we examined a gadolinium doped ceria and scandium doped zirconia as a candidate. For this examination, we investigated the microstructural and phase stability of the interface under different buffering layer conditions. According to the investigation, ceria based material induced a serious La diffusion out of the LSGM electrolyte resulted in the formation of very resistive $LaSrGa_3O_7$ phase at the interface. On the other hand zirconia based material was directly reacted with LSGM electrolyte and thus produced very resistive reaction products such as $La_2Zr_2O_7,\;Sr_2ZrO_4,\;LaSrGaO_4\;and\;LaSrGa_3O_7$. From this study we found that an improper buffering material induced the higher internal cell resistance rather than an interfacial stability.

• 대한방사성의약품학회지
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• 제2권2호
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• pp.84-95
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• 2016

Considerably increasing interest in using the theranostic isotopes/ isotope pairs of radiometals like $^{44/47}Sc$ and $^{64/67}Cu$ for diagnosis and/or therapeutic applications in the nuclear medicine procedures necessitates its reliable production and supply. Separation and purification of no-carrier-added (NCA) isotopes from macro quantitates of the irradiated target matrix along with other impurities is a cardinal procedure amongst several other steps involved in its production. Multitudinous methods including but not limited to liquid-liquid (solvent) extraction, extraction chromatography (EXC), ion exchange, electrodeposition and sublimation are routinely applied either solitarily or in combination for the separation and purification of radioisotopes depending on their production routes, radioisotope of interest and impurities involved. However, application of EXC though has shown promises towards the numerous separation techniques have not received much attention as far as its application prospects in the field of nuclear medicine are concerned. Advances in the recent past for application of the EXC resins in separation and purification of the several medically important radioisotopes at ultra-high purity have shown promising behavior with respect to their operation simplicity, acidic and radiolytic stability, separation efficiencies and speedy procedures with the enhanced and excellent extraction abilities. In this mini review we will be talking about the recent developments in the application and the use of EXC techniques for the separation and purification of $^{44/47}Sc$ and $^{64/67}Cu$ for medical applications. Furthermore, we will also discuss the scientific and practical aspects of EXC in the view of separation of the NCA trace amount of radionuclides.

• 한국식품영양과학회지
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• 제18권3호
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• pp.265-272
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• 1989

구황식품중 9종류를 감출감도가 높고 시료의 비파괴 분석이 가능한 방사화 분석법으로 무기질을 정량한 결과는 다음과 같다. 1. 부추에는 K 7099.1mg%, Cu 104.84ppm, Mo 45.45ppm, Br 40.40ppm으로 다른 식품에 비해 많은 함량을 갖고 있었다. 2. 개비름은 Zn 71.06ppm, Co 2.52ppm, La 1.4ppm 등 조혈 필수원소등을 많이 함유하였다. 3. 쑥은 Na, K, Fe, Cu, Co, Zn, Br등 대부분의 무기질이 많이 함유되어 있는 영양학적으로 우수한 식품이라 볼 수 있다. 4. 본 재료들의 K와 Na의 함량비는 부추가 796 : 1로 가장 크며 쑥, 마늘이 147 : 1, 118 : 1이고 그 이외에는 12 : $1{\sim}53$ : 1이다. 5. 부추 개비름 쑥에는 Fe와 더불어 Cu, Co가 많이 함유되어 있다. 6. 생강에는 Hg가 0.14ppm으로 다른 식품보다 $5{\sim}6$배 많았으며 Sc도 25ppb 함유하고 있다. 7. 식품속에서 극미량 존재하는 Au, Sm, Br, La, Sc등도 분석가능 하였다.

• Restorative Dentistry and Endodontics
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• 제48권4호
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• pp.36.1-36.15
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• 2023

Objectives: This study aimed to compare the effectiveness of a single-file reciprocating system (WaveOne Gold, WOG) and a multi-file rotary system (ProTaper Universal Retreatment, PTUR) in removing canal filling from severely curved canals and to evaluate the possible adjunctive effects of XP-Endo Finisher (XPF), the Self-Adjusting File (SAF), and an erbium, chromium: yttrium, scandium, gallium garnet (Er,Cr:YSGG) laser using microcomputed tomography (µCT). Materials and Methods: Sixty-six curved mandibular molars were divided into 2 groups based on the retreatment technique and then into 3 based on the supplementary method. The residual filling volumes and root canals were evaluated with µCT before and after retreatment, and after the supplementary steps. The data were statistically analyzed with the t-test, Mann-Whitney U test, analysis of covariance, and factorial analysis of variance (p < 0.05). Results: PTUR and WOG showed no significant difference in removing filling materials (p > 0.05). The supplementary techniques were significantly more effective than reciprocating or rotary systems only (p < 0.01). The supplementary steps showed no significant differences in canal filling removal effectiveness (p > 0.05), but XPF showed less dentin reduction than the SAF and Er,Cr:YSGG laser (p < 0.01). Conclusions: The supplementary methods significantly decreased the volume of residual filling materials. XPF caused minimal changes in root canal volume and might be preferred for retreatment in curved root canals. Supplementary approaches after retreatment procedures may improve root canal cleanliness.

• International Journal of Computer Science & Network Security
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• 제24권6호
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• pp.200-206
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• 2024

Laser induced breakdown spectroscopy (LIBS) technique has been used for the elemental composition of the soils. In this technique, a high energy laser pulse is focused on a sample to produce plasma. From the spectroscopic analysis of such plasma plume, we have determined the different elements present in the soil. This technique is effective and rapid for the qualitative and quantitative analysis of all type of samples. In this work a Q-switched Nd: YAG laser operating with its fundamental mode (1064 nm laser wavelength), 5 nanosecond pulse width, and 10 Hz repetition rate was focused on soil samples using 10 cm quartz lens. The emission spectra of soil consist of Iron (Fe), Calcium (Ca), Titanium (Ti), Silicon (Si), Aluminum (Al), Magnesium (Mg), Manganese (Mn), Potassium (K), Nickel (Ni), Chromium (Cr), Copper (Cu), Mercury (Hg), Barium (Ba), Vanadium (V), Lead (Pb), Nitrogen (N), Scandium (Sc), Hydrogen (H), Strontium (Sr), and Lithium (Li) with different finger-prints of the transition lines. The maximum intensity of the transition lines was observed close to the surface of the sample and it was decreased along the axial direction of the plasma expansion due to the thermalization and the recombination process. We have also determined the plasma parameters such as electron temperature and the electron number density of the plasma using Boltzmann's plot method as well as the Stark broadening of the transition lines respectively. The electron temperature is estimated at 14611 °K, whereas the electron number density i.e. 4.1 × 10¹⁶ cm^-3 lies close to the surface.

• 대한치과교정학회지
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• 제40권2호
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• pp.87-94
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• 2010

전단결합강도를 강화하기 위해 레이저를 이용한 부식과 산을 이용한 부식의 비교 연구가 많이 진행되어왔다. 본 연구에서는 Er,Cr:YSGG laser와 전통적인 산부식법을 혼합한 방법의 전단결합강도의 변화에 대한 평가를 하고자 한다. 교정적인 목적으로 발치된 64개의 건전한 소구치를 이용하여 16개씩 4개의 군으로 나누었다. 첫 번째 군은 37% 인산을 15초 적용시키는 전통적인 부식 방법을 택하였고, 두 번째 군은 물방울레이저로 1.5 W로 10초간 부식시킨 후 전통적인 산부식 방법을 시행하였다. 세 번째 군은 두 번째 군과 같지만 산부식을 먼저 시행한 후 물방울레이저로 부식시켰다. 네 번째 군은 물방울레이저를 이용하여 1.5 W로 15초간 부식시켰다. 이후 전단결합강도의 측정 및 치아 표면의 특징 관찰, 그리고 접착제잔류지수를 평가하였다. 두 번째, 세 번째 군은 첫 번째, 네 번째 군에 대하여 전단결합강도가 높게 측정되었다. 하지만 두 가지 기법의 복합사용 순서를 달리한 두 번째, 세 번째 군 사이에는 통계적으로 유의한 차이가 나지 않았다. 기존 산부식을 이용한 브라켓 접착법보다 산부식과 Er,Cr:YSGG laser를 복합적으로 사용 시, 향상된 전단결합강도를 얻을 수 있다.

• 한국가금학회지
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• 제34권1호
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• pp.23-29
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• 2007

본 연구는 희토(rare earth RE)와 Chlortetracycline (CTC)의 육계사료에 대한 첨가 효과를 구명하고자 실시하였다. 실험은 pen별 평균 개시시 체중이 비슷하도록 15수씩 평사로 배치하여 4처리구 4반복으로 희토와 항생제-CTC, 그리고 두 가지 혼용였을 경우의 효과를 관찰하고자 0, RE 100 ppm, CTC 200 ppm, RE100 ppm+ CTC200 ppm으로 하였다. 증체량, 사료 섭취량, 사료 요구율이 실험 기간중에 조사 되었으며, 실험 종료후 도살하여 체중에 대한 간 및 복강 지방의 비율과 장내미생물의 변화를 조사하였다. 시험 결과, RE 첨가구가 대조구보다 높은 증체량을 나타냈고(P<0.05), 사료 섭취량은 대조구에 비해 현저히 낮았으며(P<0.05), 사료 요구율도 대조구에 비해 16.08% 개선된 효과를 나타냈다(P<0.05). 생체중에 대한 복강지방의 비율도 RE 첨가구가 대조구 뿐만 아니라 기타 처리구에 비해서도 현저히 감소되었다(P<0.05). 생체중에 대한 간장 무게의 비율은 모든 처리구가 대조구와 비슷한 수준을 보였다. 장내미생물은 회장과 맹장의 미생물에 대한 관찰 결과, 희토첨가로 총 균수와 E. coli의 증식을 현저하게 억제되었으며(P<0.05), Salmonella는 수가 감소되는 경향을 보였으며, Lactobacillus의 수는 차이가 없었다. 이러한 결과 희토는 육계사료에서 항생제를 대체할 가능성을 보였으며, 희토의 첨가로 생산성이 개선되고 복강 지방 감소되는 경향을 보였으며, 장내 병원성 미생물을 억제하는 결과를 보였다.