Si-based anodes are promising alternatives to graphite owing to their high capacities. However, their practical application is hindered by severe volume expansion during cycling. Herein, we propose employing a carbon support to address this challenge and utilize Si-based anode materials for lithium-ion batteries (LIBs). Specifically, carbon supports with various pore structures were prepared through KOH and NaOH activation of the pitch. In addition, Si was deposited into the carbon support pores via SiH4 chemical vapor deposition (CVD), and to enhance the conductivity and mechanical stability, a carbon coating was applied via CH4 CVD. The electrochemical performance of the C/Si/C composites was assessed, providing insights into their capacity retention rates, cycling stability, rate capability, and lithium-ion diffusion coefficients. Notably, the macrostructure of the carbon support differed significantly depending on the activation agent used. More importantly, the macrostructure of the carbon support significantly affected the Si deposition behavior and enhanced the stability by mitigating the volume expansion of the Si particles. This study elucidated the crucial role of the macrostructure of carbon supports in optimizing Si-based anode materials for LIBs, providing valuable guidance for the design and development of high-performance energy-storage systems.

Zooplankton biomass is essential for understanding the quantitative structure of lake food webs and for the functional assessment of biotic interactions. In this study, we aimed to propose a biomass (dry weight) estimation method using the body length of cyclopoid copepods. These copepods play an important role as omnivores in lake zooplankton communities and contribute significantly to biomass. We validated several previously proposed estimation equations against direct measurements and compared the suitability of prosomal length versus total length of copepods to suggest a more appropriate estimation equation. After comparing the regression analysis results of various candidate equations with the actual values measured on a microbalance-using the coefficient of variation, mean absolute error, and coefficient of determination-it was determined that the Total Length-DW exponential regression equation [W=0.7775×e2.0183L; W (μg), L (mm)] could be used to calculate biomass with higher accuracy. However, considering practical issues such as the morphological similarity between species and genera of copepods and the limitations of classifying copepodid stages, we derived a general regression equation for the pooled copepod community rather than a species-specific regression equation.

The thermocatalytic decomposition of methane is a promising method for hydrogen production. To determine the cause of carbonaceous catalyst deactivation and to produce high-value carbon, methane decomposition behavior and deactivated catalysts were analyzed. The surface properties and crystallinity of a commercial activated carbon material, MSP20, used as a methane decomposition catalyst, varied with the reaction time at a reaction temperature of 900 °C. During the initial reaction, MSP20 provided a methane conversion of ≥ 50%; however, the catalyst exhibited rapid deactivation as crystalline carbon grew at surface defects; after 15 min of reaction, approximately 33% methane conversion was maintained. With increasing reaction time, the specific surface area of the catalyst decreased, whereas crystallinity increased. The R-square value of the conversion–crystallinity relationship was significantly higher than that of the conversion–specific surface area relationship; however, neither profile was linear. The activity of the activated carbon catalyst for methane decomposition is mainly determined by the complex actions of the specific surface area and defect sites. The activity was maintained after an initial sharp decline caused by the continuous growth of crystalline carbon product. This study presents the application of carbonaceous catalysts for the decomposition reaction of methane to form COx- free hydrogen, while simultaneously yielding porous carbon materials with an improved electrical conductivity.

Entomopathogenic fungi are used to produce raw materials by applying solid culture technology using grains. But there are various problems such as low production efficiency and cross-contamination. Solvum Co., Ltd. conducted research on liquid culture technology to develop a method that can overcome these shortcomings of solid culture technology. We conducted research and development on using Beauveria bassiana 331R to observe the culture according to the seed inoculation amount in a 30 L fermenter, it was carried out at 1.0 % (v/v) and 10.0 % (v/v). Although there was a difference of 1 day, 1.0 %(v/v) seed inoculation was observed to be more than twice that, and active blastospores and yield were observed at over 95.0 %. As a results, it was determined that cost and efficient production would be possible during the culture process in mass production. Based on these experiments, a 300 L fermenter was cultured with 1.0 % (v/v) seed inoculation, resulting in a yield of 1.24E+09 CFU/mL on the 6th day of cultivation. As a result of freeze-drying using the final culture medium, it was confirmed that the production yield was improved by 113.0 % compared to the control.

The economic harm and survival fear caused by environmental conflicts are most likely to become the psychological lever to drive individuals to adopt environmentally friendly behaviours. From the perspective of environmental conflict, this paper will explore the transmission mechanism of environmental conflict on individuals’ pro-environmental behaviour through three experiments.

Green product experience has become an important marketing strategy for corporations to tap potential green consumers. Based on the theory of planned behavior, this article explores the influence of attitude, subjective norm, and perceived behavioral control on consumers’ green purchasing intentions from the perspective of green product experience with consumers in China, Japan, and Korea as the research objects. Our findings suggest that green product experience of consumers in the three countries can directly affect consumers' green purchasing intentions. Green product experience has an indirect influence on consumers’ green purchasing intention through the mediating effect of attitude, subjective norm and perceived behavioral control. The multiple group comparison shows the external validity of TPB through an examination of green purchasing behavior in different cultural settings, which will help enterprises implement effective experience marketing strategies.

To investigate the effect of the catalyst and metal–support interaction on the methane decomposition behavior and physical properties of the produced carbon, catalytic decomposition of methane (CDM) was studied using Ni/SiO2 catalysts with different metal–support interactions (synthesized based on the presence or absence of urea). During catalyst synthesis, the addition of urea led to uniform and stable precipitation of the Ni metal precursor on the SiO2 support to produce Ni-phyllosilicates that enhanced the metal–support interaction. The resulting catalyst upon reduction showed the formation of uniform Ni0 particles (< 10 nm) that were smaller than those of a catalyst prepared using a conventional impregnation method (~ 80 nm). The growth mechanisms of methane-decomposition-derived carbon nanotubes was base growth or tip growth according to the metal–support interaction of the catalysts synthesized with and without urea, respectively. As a result, the catalyst with Ni-phyllosilicates resulting from the addition of urea induced highly dispersed and strongly interacting Ni0 active sites and produced carbon nanotubes with a small and uniform diameter via the base-growth mechanism. Considering the results, such a Ni-phyllosilicate-based catalyst are expected to be suitable for industrial base grown carbon nanotube production and application since as-synthesized carbon nanotubes can be easily harvested and the catalyst can be regenerated without being consumed during carbon nanotube extraction process.

Coking coal is an important raw material for coke production. In this study, in an inert atmosphere, two Chinese coking coal samples were, respectively, heated gradually to 1200 °C to release volatile and form char and coke in succession, then cooled naturally to close room temperature to age the coke. The whole heating and cooling process on carbonization were monitored in situ by simultaneous small and wide-angle X-ray scattering (SAXS-WAXS) technique based on a synchrotron radiation platform. The simultaneous structural changes of pore and skeleton in coal during carbonization are revealed for the first time. The two raw coal samples, with similar carbon content and slightly different coalification degree, undergone a carbonization process similar in whole and different in parts. The carbonization presents approximately three stages during heating process and one stage during cooling process. The coal structure changes wavily during heating and monotonously during cooling. The corresponding structural change mechanism is analyzed.

목적 : 대학생을 대상으로 디지털기기의 사용시간을 조사하고, 비침습적 눈물막파괴시간(NITBUT)을 측정하여 디지털기기가 눈물막에 미치는 영향을 알아보고자 하였다. 방법 : 2022년 8월부터 2개월간 충남 소개 대학에 재학 중인 대학생 55명을 대상으로 분석하였다. 눈물막 평 가는 Cornea 550을 이용하여 NITBUT를 측정하여 안구건조증과 정상안으로 구분하였다. 설문은 대상자의 일반 적 특성, 디지털기기의 사용 환경, 그리고 안구건조증 관련 자각 증상에 관해 총 14문항을 조사하였다. 결과 : 대상자들이 디지털기기를 사용하는 시간은 하루 평균 9.93±4.90시간이었다. 하루에 디지털기기를 8 시간 이상 사용하는 그룹에서 NITBUT가 안구건조증에 속한 경우는 58.5%였고, 8시간 미만의 21.4% 보다 유의 하게 높았다(p=0.029). 또한, 하루에 8시간 이상 디지털기기를 사용한 대상자들은 눈의 건조감과 안정피로를 더 크게 호소하였고, 연령, 성별, 콘택트렌즈, 굴절수술, 흡연, 수면시간을 보정한 후에 8시간 이상의 디지털기기의 사용은 안구건조증에 걸릴 확률을 5.18배 높였다(p=0.023). 디지털기기가 스마트폰인 경우는 NITBUT가 정상인 그룹에서 53.8%였고, 안구건조증 그룹에서는 69.0%였다(p>0.050). 결론 : 디지털기기의 사용시간이 8시간 이상 일 경우에는 비침습적 눈물막파괴시간이 짧아졌고, 안구건조증에 걸릴 확률이 높아짐을 확인할 수 있었다.