Pyrochemical processing and molten-salt reactors have recently garnered significant attention as they are promising options for future nuclear technologies, such as those for recycling spent nuclear fuels and the next generation of nuclear reactors. Both of these technologies require the use of high-temperature molten salt. To implement these technologies, one must understand the electrochemical behavior of fission products in molten salts, lanthanides, and actinides. In this study, a rotating-disk-electrode (RDE) measurement system for high-temperature molten salts is constructed and tested by investigating the electrochemical reactions of Sm3+ in LiCl–KCl melts. The results show that the reduction of Sm3+ presents the Levich behavior in LiCl–KCl melts. Using the RDE system, not only is the diffusion-layer thickness of Sm3+ measured in high-temperature molten salts but also various electrochemical parameters for Sm3+ in LiCl–KCl melts, including the diffusion coefficient, Tafel slope, and exchange current density, are determined.
The initial radionuclide migration quantity depends on the total amount of solubilized species. Geochemical modeling based on a thermodynamic database (TDB) has been employed to assess the solubility of radionuclides. It is necessary to evaluate whether the TDB describes the domestic repository conditions appropriately. An effective way to validate the TDB-based modeling results is through direct comparisons with experimentally measured values under the conditions of interest. Here, the solubilities of trivalent Sm, Eu, and Am were measured in synthetic KURT-DB3 groundwater (Syn- DB3) and compared with modeling results based on ThermoChimie TDB. Ln2(CO3)3·xH2O(cr) (Ln = Sm, Eu) solids were introduced into the Syn-DB3 and dissolved Sm and Eu concentrations were monitored over 223 days. X-ray diffraction analysis confirmed that the crystallinity of the solid compounds was maintained throughout the experiments. The dissolved Sm and Eu concentrations at equilibrium were close to the predicted solubilities of Sm2(CO3)3(s) and Eu2(CO3)3(s) based on the ThermoChimie TDB. The Am solubility measured under oversaturated conditions was comparable to the measured Eu concentrations, although they were measured under different experimental settings. More experimental data are needed for Am-carbonate solid systems with careful characterization of the solid phases to better evaluate Am solubility in domestic groundwater conditions.
Gray leaf spot caused by Stemphylium spp., is a major disease of tomatoes, and it threatens its cultivation worldwide, especially in warm and humid areas. This study was conducted on 223 tomato germplasm conserved at the National Agrobiodiversity Center to select the resources resistant to the gray leaf spot pathogen strain previously isolated in Korea, using a bioassay and genotypic analysis of the resistance gene (Sm). Two weeks after inoculation with Stemphylium lycopersici, the disease index (rated on a scale of 0-4) of gray leaf spot was assessed in detached tomato leaves. The results showed that 22 resources were resistant, with a disease index of 0-1. Additionally, 65 genetic resources were found to be moderately resistant, with a disease index between 1.0 and 2.0. Subsequently, Hybridization Probe Melting (HPM) analysis of the 22 resistant genetic resources confirmed the genotype of the gray leaf spot resistance gene (Sm). Among them, 20 genetic resources showed a homozygous resistant genotype. The resources selected in this research may contribute to the breeding of new tomato varieties resistant to gray leaf spot and may serve as a basis for further genotypic analysis studies.
In this study, we investigated the effect of the extracts of Cyrtomium fortunei J.Sm. (CFJ) on lipopolysaccharide (LPS) induced inflammation in mouse BV-2 microglial cells. Nitric oxide (NO) production and cell viability were measured using the Griess reagent and the (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) (MTT) assay. Inflammatory cytokines were detected by quantitative polymerase chain reaction (qPCR) in BV-2 microglial cells with and without CFJ extracts. Subsequently, mitogen-activated protein kinases (MAPKs) and antioxidant markers were assessed by western blot analysis. It was found that the CFJ extract significantly decreased the production of pro-inflammatory cytokines (interleukin [IL]-6, tumor necrosis factor [TNF]-, and IL-1) and NO in BV-2 microglial cells that were stimulated with LPS. In addition, the expression levels of the phosphorylation of the MAPK family (p38, c-Jun N-terminal kinases [JNK], and extracellularsignal regulated kinase [ERK]) were reduced by CFJ. Also, treatment with CFJ significantly increased the activities of superoxide dismutase type 1(SOD1) and Catalase in BV-2 microglial cells. Our results indicate that CFJ has a potent suppressive effect on the pro-inflammatory responses of activated BV-2 microglia. Therefore, CFJ has the potential to be an effective treatment for neurodegenerative diseases, as it can inhibit the production of inflammatory mediators in activated BV-2 microglial cells.
2021년 우리나라 성범죄 발생은 6,321건, 범죄률 13.5%로 교정시설에서는 성범죄 예방을 위해 다양한 프로그램을 운영하고 있지만, 여전히 성범죄의 재범률은 증가하 고 있다. 그래서 본 연구에서는 변증법적 행동 치료이론을 기반으로 성범죄자의 재범 예방 프로그램을 개발하고자 한다. 프로그램의 개발은 선행연구와 요구조사를 바탕으 로 하였다. 프로그램은 변증법적 행동치료(DBT)의 4가지 핵심기술인 마음 챙김, 정서 조절훈련, 고통 감내, 대인 관계 증진 기술로 구성하였다. 연구설계는 비동등성 대조 군 사전-사후 설계(Nonequivalent control group pretest-posttest design)로 혼 합연구 방법(Mixed Methods Design)으로 프로그램의 효과를 검증하였다. 연구대상 자는 G*Power 3.1 program의 표본 크기에 맞게 G시 교정시설에 수감 된 남성 성범 죄자 중에서 총 28명 선정하고, 무작위 할당 표집으로 실험집단 14명과 대조집단 14 명으로 배정하였다. 하지만 이감과 중도 연구 참여 거부로 인한 탈락자를 뺀 실험집단 13명과 대조 집단 12명의 자료를 최종분석하였다. 양적 분석은 SPSS 27.0 프로그램 독립표본 검증(Independent t-test)으로 동질성을 확보를 확인하고, 집단 간 변화를 이원 혼합설계 반복측정 변량분석(Repeated measures ANOVA)으로 살펴보았다. 질적 자료는 Braun과 Clark(2006)가 제시한 주제 분석방법으로 분석하였다. 연구 결 과는 다음과 같다. 첫째, 변증법적 행동치료 프로그램에 참여한 실험집단이 대조집단 보다 대인 간의 공감 반응과 성인 애착에서 통계적으로 유의미하였으며, 변화의 효과 는 추후검사에서도 통계적으로 유의미하게 유지되었다. 둘째, 프로그램 참여 경험을 분석한 결과 36개의 하위 주제, 몇10개의 상위 주제가 나타났다. 이를 분석영역인 충 동성, 공격성, 자기통제력에 재배열하였다. 충동성에서는 이성에의 의지 폭력 행동의 자발적 제어, 예측 능력의 강화, 분노의 원인 탐색 주제가 돌출되었다. 공격성에서는 파괴 본능을 건강한 에너지로 전환, 타인에 대한 적대적 감정 없애기, 낮은 자리에 서 기라는 주제가 출연했다. 자기통제력에서는 유혹을 이길 수 있는 힘의 배양, 현재의 만족보다는 미래의 성공, 규범적인 행동 목표설정이 나타났다. 연구자들은 연구 결과에 근거하여 논의하였고, 교정기관 내에서 성범죄자들의 사회 재적응을 지지할 수 있는 실천적 접근을 제안함으로써 재범을 예방하고자 하였다. 본 연구는 기존의 교정시설 에서 시도하지 않은 변증법적 행동 치료이론을 접목한 프로그램의 개발하였기에 성범 죄자 프로그램에 새로운 패러다임을 시도하였다는 점에서 선행연구들과 차이가 있다.
The effect of Sm2O3 doping on the microstructure and electrical properties of the ZPCCA-based varistors is comprehensively investigated. The increase of doping content of Sm2O3 results in better densification (from 5.70 to 5.82 g/cm3) and smaller mean grain size (from 7.8 to 4.1 μm). The breakdown electric field increases significantly from 2568 to 6800 V/ cm as the doping content of Sm2O3 increases. The doping of Sm2O3 remarkably improves the nonlinear properties (increasing from 23.9 to 91 in the nonlinear coefficient and decreasing from 35.2 to 0.2 μA/cm2 in the leakage current density). Meanwhile, the doping of Sm2O3 reduces the donor concentration (the range of 2.73 X 1018 to 1.18 X 1018 cm-3) of bulk grain and increases the barrier height (the range of 1.10 to 1.49 eV) at the grain boundary. The density of the interface states decreases in the range of of 5.31 X 1012 to 4.08 X 1012 cm-2 with the increase of doping content of Sm2O3. The dielectric constant decreases from 1594.8 to 507.5 with the increase of doping content of Sm2O3.
In this study, the electrochemical behavior of Sm on the binary liquid Al-Ga cathode in the LiCl-KCl molten salt system is investigated. First, the co-reduction process of Sm(III)-Al(III), Sm(III)-Ga(III), and Sm(III)-Ga(III)-Al(III) on the W electrode (inert) were studied using cyclic voltammetry (CV), square-wave voltammetry (SWV) and open circuit potential (OCP) methods, respectively. It was identified that Sm(III) can be co-reduced with Al(III) or Ga(III) to form AlzSmy or GaxSmy intermetallic compounds. Subsequently, the under-potential deposition of Sm(III) at the Al, Ga, and Al-Ga active cathode was performed to confirm the formation of Sm-based intermetallic compounds. The X-ray diffraction (XRD) and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) analyses indicated that Ga3Sm and Ga6Sm intermetallic compounds were formed on the Mo grid electrode (inert) during the potentiostatic electrolysis in LiCl-KCl-SmCl3-AlCl3- GaCl3 melt, while only Ga6Sm intermetallic compound was generated on the Al-Ga alloy electrode during the galvanostatic electrolysis in LiCl-KCl-SmCl3 melt. The electrolysis results revealed that the interaction between Sm and Ga was predominant in the Al-Ga alloy electrode, with Al only acting as an additive to lower the melting point.
호접란 신품종 SM 5225은 2005년 상미원에서 Phal. Golden Peoker와 Phal. Leopard Prince를 모부본으로 인공교배하여 육성한 F1개체 중에서 선발한 바탕은 진적색으로 가장자리가 백색인 이중색 계통의 계통이다. 2006년부터 2007년까지 2년에 걸쳐 실생 300개체를 양성하여 이들 중에서 영양생장과 개화특성이 우수한 개체 05-05-25를 선발하였다. 2008년과 2009년에 1차, 2차 특성검정을 통하여 품종의 안정성과 균일성을 확인하고 SM 5225으로 명명하였다. SM 5225은 화색이 진적색(RHS#69D)이며, 화형은 안아 피기로 안정되어 있다. 꽃의 길이와 폭은 각각 7.3, 9.0cm이다. 총상화서로 꽃의 볼륨이 있으며 중형 분화에 적합하다. 잎의 길이와 폭은 각각 12.0cm, 6.9cm이며, 잎은 반수직으로 배열되어 있다. 기내증식율이 높고 변이가 거의 없으며 영양생장 우수하여 재배관리가 용이하다. 2012년 10월 31일 품종등록(등록번호 제4191호)하여 종자산업법에 의해 보호받고 있다. 신품종 SM 5225는 수입종묘를 대체와 분화시장 발전에 기여할 것으로 판단된다.
In this study, the effects of Sm addition (0, 0.05, 0.2, 0.5 wt%) on the microstructure, hardness, and electrical and thermal conductivity of Al-11Si-1.5Cu aluminum alloy were investigated. As a result of Sm addition, increment in the amount of α-Al and refinement of primary Si from 70 to 10 μm were observed due to eutectic temperature depression. On the other hand, Sm was less effective at refining eutectic Si because of insufficient addition. The phase analysis results indicated that Sm-rich intermetallic phases such as Al-Fe-Mg-Si and Al-Si-Cu formed and led to decrements in the amount of primary Si and eutectic Si. These microstructure changes affected not only the hardness but also the electrical and thermal conductivity. When 0.5 wt% Sm was added to the alloy, hardness increased from 84.4 to 91.3 Hv, and electric conductivity increased from 15.14 to 16.97 MS/m. Thermal conductivity greatly increased from 133 to 157 W/m·K.
Modularization is an important benefit to overall project cost, such as construction period, manpower and logistics. In order to establish a successful modularization strategy, the optimum cost can be realized based on the Envelope Size which is allowed to be transferred to the plant site through analysis of each shape of the module. Through the analysis of the plant structure, the Envelope Size that can be transported on site in units of sizes suitable for maritime and onshore is provided, and finite element method is applied to the existing materials (A36, A572) and domestic materials (SS400, SM490, SWH400) and analyzed the results of the analysis to obtain domestic materials applicable to the plant structure frame.
BaSiO3:RE3+ (RE = Sm or Eu) phosphor powders with different concentrations of activator ions are synthesized using the solid-state reaction method. The effects of the concentration of activator ions on the structural, photoluminescent, and morphological properties of the barium silicate phosphors are investigated. X-ray diffraction data reveals that the crystal structure of all the phosphors, regardless of the type and the concentration of the activator ions, is an orthorhombic system with a main (111) diffraction peak. The grain particles agglomerate together to form larger clusters with increasing concentrations of activator ions. The emission spectra of the Sm3+-doped BaSiO3 phosphors under excitation at 406 nm consist of an intense orange band at 604 nm and three weak bands centered at 567, 651, and 711 nm, respectively. As the concentration of Sm3+ increases from 1 to 5 mol%, the intensities of all the emission bands gradually increase, reach maxima at 5 mol% of Sm3+ ions, and then decrease significantly with further increases in the Sm3+ concentration due to the concentration quenching phenomenon. For the Eu3+-doped BaSiO3 phosphors, a strong red emission band at 621 nm and several weak bands are observed. The optimal orange and red light emissions of the BaSiO3 phosphors are obtained when the concentrations of Sm3+ and Eu3+ ions are 5 mol% and 15 mol%, respectively.
우르솔릭산은 항암, 항산화, 항염증 작용과 같은 다양한 효과를 지니고 있다. 본 연구에서는 우르솔릭산이 인간 흑색종 암세포인 A375SM과 A375P 세포에 항암효과가 있는지 확인하였다. 두 세포의 생존율은 MTT assay를 통하여 확인하였으며 증식률은 Wound healing assay로 확인하 였다. 두 세포의 apoptotic body와 apoptosis 비율의 확인을 위한 DAPI 염색과 유세포 분석을 진행하였다. 그리고 웨스턴 블로팅을 통하여 흑색종 세포의 우르솔릭산의 농도에 따른 apoptosis 단백질의 유도를 조사하였다. 우르솔 릭산의 처리 농도에 따라 흑색종 세포의 생존율 감소와 증식률 감소를 확인하였다. DAPI 염색을 통하여 우르솔 릭산의 농도가 증가함에 따라 흑색종 세포의 염색체 응축 이 농도 의존적으로 증가하였고, 유세포 분석을 통하여 우르솔릭산에 대하여 농도 의존적으로 흑색종 세포의 apoptosis 비율의 증가를 확인하였다. 그리고 웨스턴 블로팅을 통해 흑색종 세포 A375SM과 A375P의 우르솔릭산 12 μM 농도에서 cleaved-PARP와 Bax의 증가와 Bcl-2의 감소를 확 인하였다. 본 연구는 우르솔릭산의 농도를 0 에서 20 μM 수준의 저농도에서 진행하였으며, 물질 처리 후 24 시간 뒤 결과를 가지고 분석하였다. 본 연구의 결과로 보아 우르솔릭산은 흑색종 세포 A375SM과 A375P에서 apoptosis 관련 단백질들의 조절을 통해 항암효과를 일으키는 것으로 사료된다.
이 연구는 ‘융합인재교육(STEAM교육)’의 철학적, 역사적, 교육학적 본질적 의미의 이론적 배경을 탐색하고 바람직한 교육현장 적용의 방법을 모색하여 국내교육대상자의 범위 확대와 더불어 STEAM 수업의 설계 과정에서 활용할 수 있는 STEAM 학습 준거의 ‘창의적 설계’ 단계에 대한 구체적 절차 모형을 개발하고 실제적 현장적용방안을 제시하고자 유아를 대상으로 하는 융합인재교육인 SM-STEAM 교수 모형을 개발하는 것이 그 목적이다.
4차 산업혁명은 창의적인 인재들을 위한 교육의 변환을 요구한다. 우리나라 공교육의 방향도 2017년 정부가 주도하여 STEAM 교육을 전 교육과정으로 세계 최초로 선포하였다. 초등학교 1~2학년 과정에 전면적인 교육과정의 개편으로 STEAM교육을 실행하는 교육의 변화는 창의적 미래 과학 기술인재 양성의 시작인 유아기에서부터 시작되어야 한다. 이에 유아교육현장의 교사나 유아가 쉽게 적용할 수 있는 유아교육을 위한 ‘SM-STEAM의 OECE모형을 개발하였다. 유아기 융합교육의 SM-STEAM은 과학(Science), 기술(Technology), 공학(Engineering), 수학 (Mathematics), 예술(Arts)의 요소를 가지며 융합교육의 주요 교수 학습법인 경험, 자료 및 현 장연구, 토론 피드백, 실험탐구, 표상전시로 이루어지는 교수·학습절차를 가지고 있다. ‘SM-STEAM,의 ‘OECE모형’은 관찰하기, 탐구하기, 구성하기, 표현하기이며 각 단계는 세부 적인 활동의 하위요인을 가지고 있다. OECE 모형은 유아교육과정에 과학을 두려워하는 교사들에게 진정한 STEAM 교육을 실현할 수 있는 시작이 될 것이고 교사는 유아들에게 OECE 모형에 의해 유아들이 가지고 있는 강점을 표현하도록 격려하고 교육과정의 흐름의 방향을 제시하는 역할을 할 수 있을 것이다. 유아기 ‘융합교육과정(STEAM)'을 위한 SM-STEAM의 ’OECE모형‘은 유아적용 STEAM 교육을 위한 시작을 열 수 있을 것이며 ‘융합인재교육 (STEAM)’ 프로그램 개발의 기초가 될 수 있을 것이다.
Human malignant melanoma is an aggressive skin cancer which has been rising at a greater rate than any other cancers. Although various new therapeutic methods have been developed in previous studies, this disease has properties of high proliferation and metastasis rate which remain obstacles that have lead to a poor prognosis in patients. It has been reported that a specific Lactobacillus extract has anti-cancer and –metastasis effect in vitro and in vivo. However, previous research has not specified precisely what effect the Lactobacillus rhamnosus GG (LGG) extract has had on human malignant melanomas. In this study, we showed that the LGG extract has anti-cancer and –metastasis effects on the human malignant melanoma cell lines, A375P and A375SM. At first, it was found that, while the LGG extract affects human neonatal dermal fibroblasts slightly, it induced the dose-dependent anti-cancer effect on A375P and A375SM by a WST-1 proliferation assay. As a result of a real-time PCR analysis, the expression patterns of several genes related to cell cycle, proliferation, and apoptosis were modulating in a manner that inhibited the growth of both malignant melanoma cell lines after the treatment of the LGG extract. Furthermore, genes related to the epithelialmesenchymal transition were down-regulated, and migration rates were also decreased significantly by the LGG extract. Our study showed that the LGG extract could be used as a potential therapeutic source.
In this study, SM45C-STKM13B hollow shaft of different thickness was joined by friction welding. After friction welding, we treated to specimen of annealing(post-weld heat treatment). The specimens were tested as-welded and post-weld heat treatment(PWHT). The mechanical properties including tensile test and vickers micro-hardness were examined. And then, the mechanical properties were compared for as-welded and PWHT in SM45C to STKM13B. Microstructure of joining part were examined in the weld interface and weld region and heat affected zone and base metal of weld parts.
Three-dimensional motion analysis systems and force plates are used for gait phase detection and ground reaction force(GRF) or ground reaction moment(GRM) data collection. But force plates as measurement systems are restricted to laboratory environments and have limitations for abnormal walking with foot dragging. Therefore the methods were proposed to compute the GRM from the kinematic data of three-dimensional motion analysis systems. Gait phase detection with kinematic data using foot velocity algorithm(FVA) was performed. The validity of gait phase detection was obtained comparing with the results of force plates. A gait model with 7 segments was composed to compute GRM. The results of gait model with kinematic data were compared with those of force plates. The result of the vertical direction is similar. But anterior-posterior direction and lateral direction show similar tendency with some gaps.
Nondestructive testing is a method of inspecting particular target objects without destructing them in industrial sites. Infrared thermal imaging is one of the nondestructive testing techniques. Among them, lock-in infrared thermography technique is a technique to detect a defect by generating a temperature difference of an object using periodic heat waves. This paper deals with the development of lock-in infrared thermography technique by using numerical analysis model for SM45C metal specimens. As a result, the appropriate frequency was determined for defect detection in SM45C metal specimen by using the established thermal behavior mechanism by periodic heat wave.
Ce0.8Sm0.2O2–δ―Sm0.1Sr0.9Cu0.2Fe0.8O3–δ dual-phase membranes were prepared with one-pot method and citric acid sol-gel process. After calcination of the powder at 850 ℃, the dual-phase membranes were prepared by uniaxially pressing the powder. The dual-phase membranes were sintered at 1150 ℃ for 5h with heating/cooling rates of 2 ℃/min. The phase structure and microstructure of the sintered membrane were studied by XRD and SEM. Elemental analysis of the membrane surface and cross section was performed. The oxygen permeation fluxes of Cu-containing dual-phase membranes were evaluated in the temperature range of 800―950 ℃ with He and CO2 as the sweep gas.