The need for the development of sustainable, efficient, and green radioactive waste disposal methods is emerging with the saturation of spent nuclear waste storage facilities in the Republic of Korea. Conventional radioactive waste management methods like using cement or glass have drawbacks such as high porosity, less chemical stability, high energy consumption, carbon dioxide production, and the generation of secondary wastes, etc. To address this gigantic issue of the planet, we have designed a study to explore the potential of alternative materials having easy processability, low carbon emissions and more chemical stability such as ceramic (hydroxyapatite, HAP) and alkali-activated materials (geopolymers, GP) to capture the simulated radioactive cobalt ions from the contaminated water and directly solidify them at low temperatures. Physical and mechanical properties of HAP alone and 15wt% GP incorporated HAP (HAP-GP- 15) composite were studied and compared. The surface of both materials was fully sorbed with an excess amount of Co(II) ions in the aqueous system. Co(II) sorbed powders were separated from aqueous media using a centrifuge machine operating at 5,000 RPM for 10 minutes and dried at 100°C for 8 hours. The dried powders were then placed in stainless steel molds, and shaped into cylindrical pellets using a uniaxial press at a pressure of 1 metric ton for 1 minute. The pellets were sintered at 1,100°C for 2 hours at a heating rate of 10°C/min. Following this, the water absorption, density, porosity, and compressive strength of the polished pellets were measured using standard methods. Results showed that HAP has a greater potential for decontamination and solidification of Co(II) due to its higher density (2.65 g/cm3 > 1.90 g/cm3), less open porosity (16.2±2.9% < 42.4 ±0.9%) and high compressive strength (82.1±10.2 MPa > 6.9±0.8 MPa) values at 1,100°C compared to that of HAP-GP-15. Nevertheless, further study with different constituent ratio of HAP and GP at various temperatures is required to fully optimize the HAP-GP matrix for waste solidifications.

A comprehensive understanding of actinide coordination chemistry and its structure is essential in many aspects of the nuclear fuel cycle, such as fuel reprocessing, waste management, reactor safety, and non-proliferation efforts. Managing radioactive waste generated during the nuclear fuel cycle has recently become more important, accordingly increasing the importance of designing appropriate waste forms and storage solutions for long-term waste disposal. Compared to the increase in the need for understanding the chemistry of major radioactive elements, the information on the local structure of the radioactive elements, especially actinides, remains unknown. To probe this issue, X-ray absorption fine structure (XAFS) can be applied. By analyzing the EXAFS (extended X-ray absorption fine structure) and XANES (X-ray absorption near edge structure), the local structure around atoms can be determined. However, the radioactive properties of the nuclides hindered the measurement of EXAFS and XANES, due to the difficulties of preparation, containment, and transfer of the sample. To measure the EXAFS of various compounds regarding the back-end nuclear fuel cycle, laboratory-based EXAFS (hiXAS, HP spectroscopy) has been introduced which can measure the EXAFS and XANES at the energy range of 5-18 keV. Compounds of Copper (Cu foil, CuO samples), Zirconium (Zr foil), and Europium (Eu2O3) were used for the verification of the laboratory -based EXAFS at a given energy range. The measured EXAFS spectrum of various compounds exhibit good agreement with the theoretical data, showing an R-factor of less than 0.02. It was found that each graph has a first peak corresponding to 2.55Å for Cu foil (Cu-Cu), 1.93Å for CuO samples (Cu-O), 3.23Å for Zr foil (Zr-Zr), and from 2.32Å to 2.34Å for Eu2O3 (Eu-O), which agree well with other values from the literature. From the result, it can be implied that this equipment can be used especially in the back-end nuclear fuel cycle field to enhance the understanding of local structure in radiochemistry.

Molten chloride salts have received considerable research attention as potential nuclear fuel and coolant candidates for molten salt reactors. However, there are several challenges, especially for structural materials due to the selective dissolution of chromium (Cr) in the molten chloride salts environment. Understanding the compatibility of uranium (U), which is used as nuclear fuel in molten salt reactors, with Cr in molten chloride salts is critical for designing the molten salt reactor structure. Therefore, in this study, the cyclic voltammetry (CV) was used to investigate the electrochemical behaviors of U and Cr. The diffusion coefficients and formal potentials were obtained. The electrochemical properties of uranium and chromium were investigated by CV in molten NaCl-MgCl2 salt at 600°C. Tungsten rods for working and counter electrode, and Ag/AgCl for reference electrode were utilized in this experiment. UCl3 made from the chemical dissolution of U rods and CrCl2 (Sigma-Aldrich, 99.99%) were used. Diffusion coefficients (D) of U and Cr were calculated by measuring reduction peak current of U3+/U and Cr2+/Cr from CV curves and using the Berzins-Delahay equation; D (U3+/U) = 3.0×10-5 cm2s-1 and D (Cr2+/Cr) = 3.3×10-5 cm2s-1. The formal potentials were also calculated by using the reduction peak potential obtained from CV results; E0’ (U3+/U) = -1.173 V and E0’ (Cr2+/Cr) = -0.321 V. The ionization tendency was investigated by comparing each reduction peak potential. The reduction peak potential Ep,c was increasing order of Ep,c (U3+/U) < Ep,c (Cr2+/Cr) < Ep,c (U4+/U3+). It can be seen that in the presence of U4+ and Cr metals, the Cr in the alloy can dissolve into Cr2+, but in the presence of U3+ and Cr metals, the Cr in the alloy does not dissolve into Cr2+. By analyzing the CV curve, diffusion coefficients and formal standard potentials were obtained. The result of comparing reduction peak potentials suggests that the nuclear fuel using U4+ should be inhibited to prevent the selective dissolution of Cr.

The ultimate objective of deep geological repositories is to achieve complete segregation of hazardous radioactive waste from the biosphere. Thus, given the possibility of leaks in the distant future, it is crucial to evaluate the capability of clay minerals to fulfill their promising role as both engineered and natural barriers. Selenium-79, a long-lived fission product originating from uranium- 235, holds significant importance due to its high mobility resulting from the predominant anionic form of selenium. To investigate the retardation behaviors of Se(IV) in clay media by sorption, a series of batch sorption experiments were conducted. The batch samples consisted of Se(IV) ions dissolved in 0.1 M NaCl solutions, along with clay minerals including kaolinite, montmorillonite, and illite-smectite mixed layers. The pH of the samples was also varied, reflecting the shift in the predominant selenium species from selenious acid to selenite ion as the environment can shift from slightly acidic to alkaline conditions. This alteration in pH concurrently promotes the competition of hydroxide ions for Se(IV) sorption on the mineral surface as the pH increases and impedes the selective attachment of selenium. The acquired experimental data were fitted through Langmuir and Freundlich sorption isotherms. From the Freundlich fit data, the distribution coefficient values of Se(IV) for kaolinite, montmorillonite, and illite-smectite mixed layer were derived, which exhibited a clear decrease from 91, 110, 62 L/kg at a pH of 3.2 to 16, 6.3, 12 L/kg at a pH of 7.5, respectively. These values derived over the pH range provide quantitative guidance essential for the safety assessment of clay mineral barriers, contributing to a more informed site selection process for deep geological repositories.

This program aims to build a specialized and converged educational platform for the training of students in the back-end nuclear fuel cycle and cultivate integrated human resources encompassing majors, generations, and fields. To achieve this, we have established an infrastructure for integrated education and training in the radiochemistry and back-end nuclear fuel cycle and operated specialized educational courses linked with special lectures, experimental practices, and field trips. Firstly, to construct an integrated educational and training infrastructure for the back-end nuclear fuel cycle, we formed a committee of experts from both inside and outside the institution and built an advanced radiochemistry laboratory equipped with physical and chemical analysis instruments. Through a comprehensive educational program involving theory, experiments, and discussions, we have established an integrated curriculum across adjacent majors and interdisciplinary studies. We also operate short-term education and experimental training programs (e.g., summer and winter schools for the back-end nuclear fuel cycle). Secondly, the program has connected leading researchers domestically and internationally, as well as the next generation of scholars. The program offers long-term educational opportunities and internships targeting both undergraduate and graduate students. To support this, we continuously offer expert colloquiums and individual research internships. Through regular committee meetings and workshops, we focus on nurturing the integrated talents necessary for the back-end nuclear fuel cycle. Through this program, students from various fields are being trained as competent integrated human resources capable of addressing various issues in the back-end nuclear fuel cycle. It is expected that this will enable us to supply specialized technical personnel in the back-end nuclear field in line with mid-to-long-term demands.

본 연구의 목적은 유아의 어머니를 대상으로 놀이명상 프로그램이 어머니의 마음챙김과 심리적 안녕감 및 양육태도 증진의 효과성을 검증하고자 하는 데 있다. 연구대상은 K 시 어린이집에 재원 중인 유아들의 어머니를 대상으로 참가를 원하는 어머니 30명에 대한 동질성을 고려하여 15명은 실험집단, 다음 15명은 통제집단에 배정하였다. 본 연구에 사용한 측정도구는 박성현(2006)의 마음챙김 척도, Ryff(1989)의 심리적 안녕감 척도 (Psychology well-being Scale : PWBS)를 김명소 및 차경호(2001)가 번안하여 서현주(2006)가 재구성한 척도, 김은경(2007)이 사용한 양육태도 척도이다. 본 연구의 자료처리는 SPSS WIN 14.0 프로그램을 사용하여 분석하였고, 유아어머니의 마음챙김, 심리적 안녕감, 양육태도를 실험 전후에 실시하여 두 집단 간의 차이를 살펴보는 paired t-test를 실시하였다. 본 연구의 결과는 첫째, 마음챙김의 현재자각과 주의집중, 비판단적 수용과 탈중심주의가 놀이명상 프로그램을 실시한 집단은 통제집단보다 향상되었다. 둘째, 놀이명상 프로그램이 유아의 어머니의 긍정적 대인관계와 자율성, 환경에 대한 지배력과 삶의 목적을 찾게 되는 등의 심리적 안녕감을 증진시킨다는 결과를 얻었다. 셋째, 놀이명상 프로그램 이 권위주의적 통제, 과잉 보호적 태도로부터 벗어나, 성취적이며 적극적인 참여, 일관성 있는 규제 등의 바람직한 양육태도 증진에 효과적임을 밝혔다. 본 연구의 결론은 유아의 자녀를 둔 어머니들이 놀이명상 프로그램을 통하여 마음챙김 수준이 향상되고 심리적 안녕감이 증진되었으며, 양육태도가 부분 증진되었다. 이는 본 연구의 놀이명상 프로그램이 건강한 아동발달과 행복한 가족관계, 어머니 역할의 지원에 기여할 수 있음을 시사한다.

본 연구는 고도(古都)육성사업 교육프로그램을 진행 중인 익산시를 중심으로 교육 참여자 의식과 만족도를 도출하기 위하여 교육생을 중심으로 설문지 및 인터뷰 조사를 통해 향후 프로그램 개발과 운영을 위한 기초자료를 마련하고자 하며 결론은 다음과 같다. 교육프로그램을 통해 지역 고도육성사업에 발전도움여부는 지역사회에 생업활동을 통해서 사실을 인지하고 참여자 대부분이 긍정적인 참여의향이 있는 것으로 나타났다. 고도육성 교육프로그램 관심분야는 역사문화인식, 고도문화가꾸기, 현장체험 등의 순으로 선호하는 것이 나타났다. 교육 후 심화교육과정 필요 여부에서 대부분의 교육생들이 심화교육 필요성을 강조하였고 교육 분야에는 문화유적관련 교육, 고도보존계획 및 육성사업, 전반적인 고도육성사업 등 순으로 나타났다. 향후 고도보존사업의 이해와 다양한 교육 프로그램을 고려한 심화교육 통해서 긍정적인 이미지를 지역사회에 유입시키고 부정적인 이미지를 해소하는 여건과 인식의 변화 프로그램 개발이 지속적으로 추진되어야 한다고 판단한다.

최근 들어 급속한 사회 변화는 새로운 사회 전반의 현상에 적응할 수 있는 역량을 학습하거나 인지하기도 전에 보다 많은 변화를 이루어내고 있고 이로 인한 청소년들의 사회 전반의 변화에 대한 부적응은 학교현장에서는 물론 청소년들의 생활 전반의 문제로 야기되어지고 있다. 그리고 “학교 폭력” 또는 “학교폭력 예방” 등 학교현장 청소년들의 문제해결과 관련하여 청소년들의 적응이나 역량개발 등의 다양한 프로그램이 정부 또는 상위 기관이나 해당기관 주도의 정책에 의해 대부분이 이루어지고 있다. 이에 본 연구는 2011∼2012년 경기도 내 인문⦁전문계열 고등학교 2학년에 재학 중인 청소년을 대상으로 코칭 프로그램 적용 후 소감문의 기술 내용에 기초한 청소년들이 인지하는 문제를 토대로 정책적이거나 형식적이 아닌 그들의 요구를 직접 반영한 청소년이 요구하는 적응을 위한 역량 개발 지표의 정보를 얻고자 질적 연구를 바탕으로 연구 되었다. 또한 본 연구에 적용한 코칭프로그램을 학교현장 청소년들에게 제공함에 있어 적응과 역량개발을 위한 프로그램의 필요성에 대한 연구의 정보를 제공하고자 한다.