Owing to its low cost, easy fabrication process, and good ionic properties, aqueous supercapacitors are under strong consideration as next-generation energy storage devices. However, the limitation of the current collector is its poor electrochemical stability, leading to low energy storage performance. Therefore, a reasonable design of the current collector and the acidic electrolyte is a necessary, as well as interfacial engineering to enhance the electrochemical performance. In the present study, graphite foil, with excellent electrochemical stability and good electrical properties, is suggested as a current collector of aqueous supercapacitors. This strategy results in excellent electrochemical performance, including a high specific capacitance of 215 F g−1 at a current density of 0.1 A g−1, a superior high-rate performance (104 F g−1 at a current density of 20.0 A g−1), and a remarkable cycling stability of 98 % at a current density of 10.0 A g−1 after 9,000 cycles. The superior energy storage performance is mainly ascribed to the improved ionic diffusion ability during cycling.

In this study, when stem cell culture solution is used as a cosmetic ingredient, one of the most prominent problems is that the ingredients generally have low thermal stability. Therefore, in this study, in order to find out how the stem cell culture medium is heated or preserved at high temperature, the effect of various effects of stem cells on the various effects of the stem cells was investigated. Investigated. As a result of the experiment, the wound healing assay confirmed that the cell migration increased after 6 hours, and after 24 hours, it was confirmed that the cell mobility was increased and cell division was promoted, thereby being concentrated. As a result of investigating the amount of transdermal water loss by preparing a cosmetic product containing stem cell culture solution, it was confirmed that the culture solution addition group showed an improvement rate of 31% compared to the non-added group, thereby helping in skin wound recovery. As a result of this, it is considered that this point should be considered when the stem cell culture medium is used as an active ingredient in cosmetics in the future.

This study was carried out to investigate milling's effect on the pasting properties and storage stability of dry-milled rice flour. Rice flour's moisture content was increased from 9.48% to 9.80% after going through a rice polisher, and the crude fat content of rice flour was decreased from 0.91% to 0.62% after going through a rice polisher. In the color index of rice flour, the rice polisher was only affected by yellowness. The pasting properties were verified through RVA, and it was confirmed that the use of a rice polisher had no significant effect on the pasting properties. As a result of observing the changes in fatty acid value, it was ascertained that the storage period could be increased using the rice polisher. These results suggest that the rice polisher can increase the storage period without changing the pasting properties.

본 연구는 길안천의 저서성대형무척추동물 군집구조를 과거와 비교하여 분석하고자, 2018년 총 2회 조사를 실시하여 Lee (2004)의 결과와 비교하였다. 2018년 출현종수는 2003년과 비교하여 총 45종이 증가하였으며, 그중 EPT 분류군이 24종, OCH 분류군이 18종이 추가로 조사되었다. 군집분석 결과, 다양도지수 (Hʹ)와, 풍부도지수 (Rʹ)는 증 가하였고, 우점도지수 (DI)는 감소하는 경향을 보였다. 섭식기능군은 주워먹는무리 (GC)에 속하는 종이 과거대비 11종이 추가로 발견되어 가장 높게 나타났고, 서식기능군 의 경우 붙는무리 (CL)가 41종으로 가장 많은 종이 출현하였다. 군집안정성에서는 특성군 I그룹이 2003년에 57.1%, 2018년에 61.5%로 가장 높은 출현율을 보였다. 생물학적 수질평가 결과, 과거 평균 ‘II등급’의 수질등급과 ‘보통’의 환경상태에서 2018년에는 평균 ‘Ia’등급의 수질과 ‘매우 양호’한 환경상태를 나타냈다. 2018년의 이화학적 요인과 생물학적 요인과의 상관관계 분석결과, pH 및 BOD는 개체 수, 우점도지수 (DI), 풍부도지수 (Rʹ), 다양도지수 (Hʹ), 균등도지수 (Jʹ)에 유의한 상관관계를 나타냈다. 유사도 분석 결과, 각 연도별로 두 개의 유사군으로 분류되었다. 길안천 수계가 취수시설 및 생태공원, 하천정비사업을 진행하면서 발생한 물리적 교란 이후 시간이 지남에 따라 물 흐름 개선과 다양한 미소서식처 형성을 통해 종 다양성 및 풍부도가 높게 나타난 것으로 판단되며, 향후, 제한적인 구간의 하천정비공사로 인한 하상 교란과 수질과의 상관 관계가 저서성대형무척추동물의 군집구조와 군집안정성에 미치는 영향에 대해 추가적인 연구가 필요할 것으로 사료된다.

With respect to spent nuclear fuels, disposal containers and bentonite buffer blocks in deep geological disposal systems are the primary engineered barrier elements that are required to isolate radioactive toxicity for a long period of time and delay the leakage of radio nuclides such that they do not affect human and natural environments. Therefore, the thermal stability of the bentonite buffer and structural integrity of the disposal container are essential factors for maintaining the safety of a deep geological disposal system. The most important requirement in the design of such a system involves ensuring that the temperature of the buffer does not exceed 100℃ because of the decay heat emitted from high-level wastes loaded in the disposal container. In addition, the disposal containers should maintain structural integrity under loads, such as hydraulic pressure, at an underground depth of 500 m and swelling pressure of the bentonite buffer. In this study, we analyzed the thermal stability and structural integrity in a deep geological disposal environment of the improved deep geological disposal systems for domestic light-water and heavy-water reactor types of spent nuclear fuels, which were considered to be subject to direct disposal. The results of the thermal stability and structural integrity assessments indicated that the improved disposal systems for each type of spent nuclear fuel satisfied the temperature limit requirement (< 100℃) of the disposal system, and the disposal containers were observed to maintain their integrity with a safety ratio of 2.0 or higher in the environment of deep disposal.

Probiotic-derived bacteriocins have attracted considerable attention as an alternative to synthetic preservatives in the food industry, as synthetics are harmful to health. Lactobacillus gasseri G2 isolated from infant feces has been demonstrated to possess probiotic properties such as bile salt and acid tolerance, antibiotic resistance, and broad antimicrobial activity. Bacteriocin was partially purified by acetone precipitation and characterized for several properties. It was found to be highly thermostable and resistant to heating at 120oC for 15 min. Bacteriocin activity remained unaffected with changes in the pH range from 2.0 to 10.0 and by solvents such as acetone, methanol, ethanol, and butanol. The antimicrobial activity was not affected by α-amylase, lysozyme, and lipase, but was reduced after treatment with protease, trypsin, and proteinase K, suggesting that it has a proteinaceous nature. Bacteriocin inhibited a broad range of target bacteria belonging to both Gram-positive and Gram-negative groups: Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus, Clostridium perfringens, Escherichia coli O157:H7, Enterobacter sakasakii, Salmonella Enteritidis, Shigella flexneri, Shigella boydii, Vibrio parahaemolyticus, and Vibrio vulnificus. Bacteriocin appeared as a smear of the protein band with a molecular weight between 2-5 kDa, which showed a clear zone of inhibition after bioassay. The high thermostability and acid/alkali stability of bacteriocin reflect its potential commercial significance.

Background: The hip muscle plays various roles. Several types of functional performance tests are used for the assessment of patients with various lower extremity injuries. Hip muscle functions are important to test the performance of maintaining the spine, pelvic, and leg during bridging exercise. We designed a novel functional performance test tool, which we named close kinetic chain dynamic lower extremity stability (CKCLE) test to assess hip muscle functions. Objects: The purpose of this study was to determine the relationship between CKCLE test and hip extensor, external rotator, and abductor strengths. Methods: Twenty-two subjects were recruited in the present study (13 males and 9 females). The hip extensor, external rotator, and abductor muscle strengths were measured using a Smart KEMA strength sensor. When the examiner said “Go”, the subject performed the CKCLE test by moving one leg from the floor and touching the opposite knee and then return to the floor while maintaining the bridging position. The subjects attempted as many “touches” as possible in the allotted time (20 seconds) during the maximal tests. The correlation between the hip muscle (extensor, external rotator, and abductor) strength of the supporting leg and the number of CKCLE tests performed in 20 seconds was determined using the Pearson correlation. Results: Hip extensor (r = 0.626, p < 0.05), hip external rotator (r = 0.616, p < 0.05), and hip abductor muscle strengths (r = 0.475, p < 0.05) positively correlated with the number of CKCLE tests performed. Conclusion: We designed a CKCLE test and found that performance in the test correlated with hip extensor, external rotator, and abductor muscle strengths. The result suggests that the CKCLE test can be applied as a performance test to assess the functions of the hip extensor, external rotator, and hip abductor muscles.

In the present study, we investigated the austenite stability of a sintered Fe-based nanocrystalline alloy. The volume fraction of austenite was measured based on the X-ray diffraction data of sintered Fe-based nanocrystalline alloys, which were prepared by high-energy ball milling and spark plasma sintering. The sintered alloy samples showed a higher volume fraction of austenite at room temperature as compared to the equilibrium volume fraction of austenite obtained using thermodynamic calculations, which resulted from the nanosized crystalline structure of the sintered alloy. It was proved that the austenite stability of the sintered Fe-based alloy increased with a rise in the amount of austenite stabilizing elements such as Mn, Ni, and C; however, it increased more effectively with a decrease in the actual grain size. Furthermore, we proposed a new equation to predict the martensite starting temperature for sintered Fe-based alloys.

Ti0.5Al0.5N/CrN nano-multilayers, which are known to exhibit excellent wear resistances, were prepared using the unbalanced magnetron sputter for various periods of 2–7 nm. Ti0.5Al0.5N and CrN comprised a cubic structure in a single layer with different lattice parameters; however, Ti0.5Al0.5N/CrN exhibited a cubic structure with the same lattice parameters that formed the superlattice in the nano-multilayers. The Ti0.5Al0.5/CrN multilayer with a period of 5.0 nm exceeded the hardness of the Ti0.5Al0.5N/CrN single layer, attaining a value of 36 GPa. According to the low-angle X-ray diffraction, the Ti0.5Al0.5N/CrN multilayer maintained its as-coated structure up to 700oC and exhibited a hardness of 32 GPa. The thickness of the oxidation layer of the Ti0.5Al0.5N/CrN multilayered coating was less than 25% of that of the single layers. Thus, the Ti0.5Al0.5N/CrN multilayered coating was superior in terms of hardness and oxidation resistance as compared to its constituent single layers.

본 연구에서는 인체에 해가 없으며 항균작용 및 항산화 효과가 있는 오배자, 계피, 로즈마리 추출물을 이용하여 천연방부제 소재로서의 활용 가능성을 연구하였다. 실험식물의 추출방법으로는 계피의 경우 70% ethanol 추출, 오배자는 열수추출법, 로즈마리는 70% ethanol 추출과 열수추출법을 이용하였다. 실험 방법으로는 항균력, DPPH를 통한 항산화능, 화장품의 challenge test, 화장품 안정성 및 안전성 평가를 진행하였다. 시험 결과, 항균력 시험에서 오배자 추출물은 세균류, 계피 추출물은 진균류에서 항균력이 우수, 로즈마리 추출물의 경우 항균력이 미비해 제외, 복합 추출물(오배자·계피)의 경우는 1:1비율로 조합한 복합 추출물(complex C)에서 항균효과, 복합 추출물의 최소저해농도(MIC)와 최소살균농도(MBC)에서는 5종의 실험균주에서 억제효과와 살균효과, 천연 단일 추출물과 복합 추출물(complex C)에서는 항산화능이 확인 되었다. 또한 합성 방부제 대신 complex C 10%를 화장품에 적용한 시험에서 제형의 안정성 및 안전성이 확인되었다. 따라서 본 연구를 통해 천연방부제 원료로서의 발전 가능성을 확인할 수 있었다.

In this paper, AgCl/Ag3PO4/diatomite photocatalyst is successfully synthesized by microemulsion method and anion in situ substitution method. X-ray diffraction (XRD), photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), and ultraviolet-visible spectroscopy (UV-Vis) are used to study the structural and physicochemical characteristics of the AgCl/Ag3PO4/diatomite composite. Using rhodamine B (RhB) as a simulated pollutant, the photocatalytic activity and stability of the AgCl/Ag3PO4/diatomite composite under visible light are evaluated. In the AgCl/Ag3PO4/diatomite visible light system, RhB is nearly 100 % degraded within 15 minutes. And, after five cycles of operation, the photocatalytic activity of AgCl/Ag3PO4/diatomite remains at 95 % of the original level, much higher than that of pure Ag3PO4 (40 %). In addition, the mechanism of enhanced catalytic performance is discussed. The high photocatalytic performance of AgCl/Ag3PO4/diatomite composites can be attributed to the synergistic effect of Ag3PO4, diatomite and AgCl nanoparticles. Free radical trapping experiments are used to show that holes and oxygen are the main active species. This material can quickly react with dye molecules adsorbed on the surface of diatomite to degrade RhB dye to CO2 and H2O. Even more remarkably, AgCl/Ag3PO4/diatomite can maintain above 95 % photo-degradation activity after five cycles.