As the demand for sustainable hydrogen (H₂) production grows, catalytic decomposition of methane (CDM) has emerged as a CO2- free pathway for H2 generation, producing valuable multi-walled carbon nanotubes (MWCNTs) as byproducts. This study examines the role of fuel type in shaping the properties and performance of NiOx/AlOx catalysts synthesized via solution combustion synthesis (SCS). Catalysts prepared with citric acid, urea, hexamethylenetetramine (HMTA), and glycine exhibited varying NiO nanoparticle (NP) sizes and dispersions. Among them, the HMTA catalyst achieved the highest Ni dispersion (~ 3.2%) and specific surface area (21.6 m2/ gcat), attributed to vigorous combustion facilitated by its high pH and amino-group-based fuel. Catalytic tests showed comparable activation energy (55.7–59.7 kJ/mol) across all catalysts, indicating similar active site formation mechanisms. However, the HMTA catalyst demonstrated superior CH4 conversion (~ 68%) and stability, maintaining performance for over 160 min under undiluted CH₄, while others deactivated rapidly. MWCNT characterization revealed consistent structural properties, such as graphitization degree and electrical conductivity, across all catalysts, emphasizing that fuel type influenced stability rather than MWCNT quality. H2 temperature-programmed reduction ( H2-TPR) analysis identified moderate metal-support interaction (MSI) in the HMTA catalyst as a key factor for optimizing stability and active site utilization. These findings underscore the importance of fuel selection in SCS to control MSIs and dispersion, offering a strategy to enhance catalytic performance in CDM and other thermocatalytic applications.

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.

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.

2021년 4월부터 8월에 제주시의 비닐하우스에서 재배되는 목이버섯에서 거저리 일종이 발견되었으며, 그를 동정한 결과 제주진주거저리 (Platydema takeii Nakane, 1956)로 확인되었다. 상업적으로 재배되는 버섯에 있어서 거저리 해충으로 인한 우리나라의 첫 번째 피해 사례이다. 여 기서는 이 해충의 피해 증상과 성충 및 유충의 진단형질을 제공하고자 한다.

Celecoxib, a cyclooxygenase (COX)-2 selective inhibitor, was approved as a non-steroidal anti-inflammatory drug (NSAID), and this therapeutic application has been expanded to several other diseases, including colon cancer. Notably, a treatment strategy combining the use of celecoxib and radiation therapy has been employed for improving the control of local cancers. In this study, we examined the effect of celecoxib on irradiation-induced intestinal damage. The twenty four mice (BALB/c) were divided into four groups; 1) sham-irradiated control group, 2) celecoxib-treated group, 3) irradiated group, and 4) celecoxib-treated irradiation group. Mice were orally administered celecoxib at a dose of 25 mg/kg in a 0.1 mL volume, daily for 4 days after irradiation exposure (10 Gy). Then, histological examinations of the jejunal villous height, crypt survival, and crypt size were performed. The expression of COX-2 after administration of celecoxib in irradiated mice was examined by employing immunohistochemistry, Western blotting, and qPCR analysis. The jejunal villi height and the crypt survival were reduced in the irradiation group compared with the sham-irradiated group. Celecoxib treatment in irradiation mice even more decreased those indicators. Crypt size was increased in the radiation group compared to the sham-irradiated control group, whereas the size was decreased in the celecoxibtreated irradiation group compared with the group exposed to the radiation injury. COX-2 expression was detected in the crypt of the small intestine, and COX-2 expression was increased in the crypt lesion following radiation exposure. However, COX-2 expression was reduced in the celecoxib-treated irradiation group. Therefore, in the present study, we confirmed that celecoxib treatment after irradiation aggravated the irradiation-induced intestinal damage. These results suggest that a caution need to be administered when celecoxib treatment is performed in combination with radiation therapy for cancer treatment.