In this work, we investigated the photo-degradation performance of MnO2-SiC fiber-TiO2 (MnO2-SiC-TiO2) ternary nanocomposite according to visible light excitation utilizing methylene blue (MB) and methyl orange (MO) as standard dyes. The photocatalytic physicochemical characteristics of this ternary nanocomposite were described by X-ray diffraction (XRD), scanning electron microscopy (SEM), tunneling electron microscopy (TEM), ultraviolet-visible (UV-vis), diffuse reflectance spectroscopy (DRS), electrochemical impedance spectroscopy (EIS), photocurrent and cyclic voltammogram (CV) test. Photolysis studies of the synthesized MnO2-SiC-TiO2 composite were conducted using standard dyes of MB and MO under UV light irradiation. The experiments revealed that the MnO2-SiC-TiO2 exhibits the greatest photocatalytic dye degradation performance of around 20 % with MB, and of around 10 % with MO, respectively, within 120 min. Furthermore, MnO2-SiC-TiO2 showed good stability against photocatalytic degradation. The photocatalytic efficiency of the nanocomposite was indicated by the adequate photocatalytic reaction process. These research results show the practical application potential of SiC fibers and the performance of a photocatalyst composite that combines these fibers with metal oxides.

The development of thermoelectric (TE) materials to replace Bi2Te3 alloys is emerging as a hot issue with the potential for wider practical applications. In particular, layered Zintl-phase materials, which can appropriately control carrier and phonon transport behaviors, are being considered as promising candidates. However, limited data have been reported on the thermoelectric properties of metal-Sb materials that can be transformed into layered materials through the insertion of cations. In this study, we synthesized FeSb and MnSb, which are used as base materials for advanced thermoelectric materials. They were confirmed as single-phase materials by analyzing X-ray diffraction patterns. Based on electrical conductivity, the Seebeck coefficient, and thermal conductivity of both materials characterized as a function of temperature, the zT values of MnSb and FeSb were calculated to be 0.00119 and 0.00026, respectively. These properties provide a fundamental data for developing layered Zintl-phase materials with alkali/alkaline earth metal insertions.

As part of the research program “Freshwater Prokaryotic Organisms Research and Discovery,” freshwater samples were collected from the Nakdonggang River. After plating the samples on several culture media and incubating aerobically, approximately 900 bacterial strains were isolated and identified using 16S rRNA gene sequences. Among the bacterial isolates showing higher than 98.7% 16S rRNA gene sequence similarity with those of already confirmed bacterial species previously unreported in Korea, 29 strains were selected. These strains were phylogenetically diverse and belonged to 3 phyla, 6 classes, 13 orders, and 21 genera. At the genus level, these previously unreported species were found to be affiliated with Novosphingobium, Sphingomonas, Polymorphobacter, Croceibacterium, Devosia, Endobacterium, Agaricicola, Bradyrhizobium, Paracoccus, and Pseudotabrizicola of the class Alphaproteobacteria; Undibacterium, Azonexus, and Dechloromonas of the class Betaproteobacteria; Acinetobacter and Budvicia of the class Gammaproteobacteria; Streptomyces, Nocardioides, Mycobacterium, and Cellulomonas of the phylum Actinomycetota; Flavobacterium and Pedobacter of the phylum Bacteroidota. These species were further characterized by examining their Gram reaction, colony and cell morphologies, biochemical properties, and phylogenetic positions. Detailed descriptions of these 29 previously unreported species are provided.

갯까치수염은 다육성의 2년생 초본 자생식물로서, 제주도, 울릉도를 비롯하여 남해안 지역에서 자라며 자생지의 환경에 맞게 내염성이 크다는 특징이 있고, 다양한 환경에 적응하며 관상가치가 높다. 관련 문헌을 보면 발아조건과 개화조절에 대한 연구만 보고되었고 그 중간단계인 재배에 관한 연구가 부족하여 대량생산을 위한 공정육묘법 개발의 일환으로 이 실 험을 수행하였다. 실험은 플라스틱온실 내에서 발아시킨 1cm 전후의 묘를 50, 128, 200구 트레이에 이식하여 한국원시표 준액(N-P-K-Ca-Mg, 15-3-6-8-4)을 각각 권장 EC농도의 0, 0.5, 1, 2배 농도로 매일 5분간 순환식으로 저면 관수하여 6주간 재배 후 초장, 근장, 엽수, 뿌리수, SPAD, 생체중, 건물 중을 측정하였다. 갯까치수염 생육은 플러그 셀 크기 50셀에 서 생육이 가장 높았다. 양액농도에 따른 갯까치수염의 생육 은 0.5배액에서 초장과 근장의 수치가 가장 높았으며, 모든 생육지표가 양액 농도변화에 따른 차이가 발생하는 것으로 나 타났고 실질적인 총 생산량의 지표라고 할 수 있는 지상부와 지하부의 건물중에 영향을 미치지 않았다는 결과가 나온 것으 로 미뤄 육묘단계에서 양액의 농도가 셀 크기보다 갯까수치염 의 묘 생육에 더 영향이 큰 것으로 보인다. 갯까치수염의 조직 충실도 면에서 0.5, 1, 2배액의 200구에서 가장 높은 결과값 들이 나왔다. 결과적으로 기존 원시표준액에 비해 생장에 유 리한 결과를 보이며 비료도 절약할 수 있는 0.5배 양액처리조 건이 갯까치수염 육묘 재배에 더 효율적이였다.

This paper explores the professional identities of four Filipino English teachers (FETs) who instruct international students at a language academy in Bonifacio Global City (BGC), a special district for the Philippines’ globalization. Employing a narrative inquiry approach, data was gathered through individual interviews, and subsequently analyzed using a thematic analysis framework. The findings indicate that the participants assume three distinct roles within the academy. As experts in English language teaching, they consider themselves the equal of, or even superior to, native English-speaking teachers, which they attribute to their language proficiency, pedagogical skills, and content-based teaching. In their role as educational caretakers, they prioritize their students’ well-being, providing motivation for English language learning, and offering emotional support. Furthermore, they identify themselves as international teachers, having deliberately chosen BGC as their career destination to foster multiculturalism and global citizenship. This study is of particular significance, as it scrutinizes the roles of FETs, frequently categorized as “non-native teachers,” within the context of globalization.

To ensure a systematic and integrated approach to defense safety management, individual safety management regulations have been consolidated into the National Defense Safety Directive. However, despite being enacted after the enforcement of the Severe Accident Punishment Act, the National Defense Safety Directive does not incorporate the contents of the Serious Accident Punishment Act. This omission is likely to cause confusion in safety management. In this paper, a PDCA analysis of the Severe Accident Punishment Act and the National Defense Safety Directive was conducted to identify area for improvement and supplementation in the Directive. Chapter 3 proposes amendments to clearly define the scope and responsibilities of safety management, implement serious accident prevention measures and inspections, and establish the penalties for those involved. These amendments aim to ensure faithful compliance with the Severe Accident Punishment Act. Chapter 4 emphasizes the implementation and inspection of risk assessments to enhance the effectiveness of safety accident prevention and preparation, thereby ensuring the completeness of the PDCA cycle.