Cellulose has experienced a renaissance as a precursor for carbon fibers (CFs). However, cellulose possesses intrinsic challenges as precursor substrate such as typically low carbon yield. This study examines the interplay of strategies to increase the carbonization yield of (ligno-) cellulosic fibers manufactured via a coagulation process. Using Design of Experiments, this article assesses the individual and combined effects of diammonium hydrogen phosphate (DAP), lignin, and CO2 activation on the carbonization yield and properties of cellulose-based carbon fibers. Synergistic effects are identified using the response surface methodology. This paper evidences that DAP and lignin could affect cellulose pyrolysis positively in terms of carbonization yield. Nevertheless, DAP and lignin do not have an additive effect on increasing the yield. In fact, combined DAP and lignin can affect negatively the carbonization yield within a certain composition range. Further, the thermogravimetric CO2 adsorption of the respective CFs was measured, showing relatively high values (ca. 2 mmol/g) at unsaturated pressure conditions. The CFs were microporous materials with potential applications in gas separation membranes and CO2 storage systems.

Semiconductor-based photocatalytic carbon dioxide ( CO2) reduction is of great scientific importance in the field of alleviating global warming and energy crisis. Surface amine modification and cocatalyst loading on the catalyst surface could improve CO2 adsorption capacity and photogenerated charge separation. Herein, amine-modified brookite–TiO2 ( NH2–B–TiO2) coupled metal species (Cu, Ag, Ni(OH)2) cocatalysts have been successfully synthesized by chemical reduction method. The photocatalytic CO2 reduction results show that the CH4 production rates of NH2– B–TiO2/Cu, NH2– B–TiO2/Ag, and NH2– B–TiO2/Ni(OH)2 are 3.2, 12.5, and 1.7 times that of NH2– B–TiO2 (0.74 μmmol g− 1 h− 1), respectively. Results show the introduction of metal species on the surface of the catalyst enhances the absorption range of sunlight and the photogenerated carrier separation efficiency, resulting in enhancing the performance of photocatalytic CO2 reduction. This work provides a strategy for designing metal species-loaded amine-modified brookite–TiO2 by surface/interface regulation to improve photocatalytic efficiency.

Nasopharyngeal stenosis is defined as a morphological transition of narrowing at the nasopharyngeal region. A 2-yearold, castrated male, Korean short hair cat was referred to the animal medical center, Gyeongsang National University. According to clinical signs, diagnostic imaging, and physical examination, nasopharyngeal stenosis was diagnosed. The staphylectomy was performed using a CO2 laser, and there were not any post-operative complications. The patient was discharged in two days. This report describes the case of nasopharyngeal stenosis in cat and represents that laser ablation could be a good option for surgical management of the nasopharyngeal region with a low complication rate.

이 연구 논문은 기후 변화에 대한 전 세계적인 우려와 온실 가스 배출 감소를 위한 필수적인 요구에 대응하여 마 이크로기공 고분자(PIM-1)의 이용을 탐구한 것이다. 연구는 PIM-1 막을 이산화탄소(CO2) 가스 분리 막으로 사용하는 현대적 인 소재로서의 응용에 집중하고 있다. 연구는 PIM-1 막의 합성, 분자량 제어, 그리고 제각각의 특성 분석 기술을 통해 포괄적 인 통찰을 제공하며, 이러한 특성 분석 기술을 통해 PIM-1의 고유한 교차결합 및 강성 구조에서 비롯된 내재적 다공성이 특 히 이산화탄소의 선택적 투과에 활용되고 있다. 논문은 PIM-1의 가교된 구조로부터 비롯된 내재적 다공성이 특히 이산화탄 소의 선택적 투과에 활용되고 있다. 논문은 PIM-1의 튜닝 가능한 화학적 특성을 강조하며, 가스 분리 막의 맞춤 및 최적화를 가능케 하는 특성에 대한 이해를 제시하고 있다. 분자량을 통제함으로써 고분자량(H-PIM-1) 막은 낮은 분자량 대비 더 뛰어 난 CO2 투과성과 선택성을 나타내며, 이를 통해 PIM-1 막의 특성을 조절하는 데 분자량의 중요성을 강조하고 있다. 연구 결 과는 PIM-1 막 특성을 조절하는 데 분자량이 중요한 역할을 하는 것을 강조하며, 이는 기후 변화의 긴급한 글로벌 도전에 대 응하기 위한 효율적이고 선택적인 CO2 포집을 위한 차세대 막 기술의 발전에 기여하고 있다.

Passengers on public buses operating in the metropolitan area are exposed to the closed indoor air for minutes to hours. The indoor air quality of buses is mostly controlled through ceiling-mounted ventilation and filtration devices. A simulation study using a commercial code was conducted for fluid flow analysis to evaluate the potential effectiveness of an air purifier that can be inserted into bus windows to supply clean air from the outside to the inside. As a result of field measurements, the average CO2 concentration inside the bus during morning and evening rush hours ranged from 2,106±309 ppm to 3,308 ± 255 ppm depending on the number of passengers on board. This exceeded the Guideline for Public Transportation. The optimal installation position of an air purifier appeared to be the front side of the bus. In fact, even a low diffusing flow velocity of 0.5m/s was effective enough to maintain a low concentration of CO2 throughout the indoor space. Based on numerical analysis predictions with 45 passengers on board, the maximum CO2 concentration in the breathing zone was 2,203 ppm with the operation of an air purifier.

PURPOSES : This study was conducted to evaluate the physical properties of the RAP 50 asphalt mixture containing polymer modified rejuvenator and warm-mix additive to improve the recycling rate of RAP and reduce CO2 emission. METHODS : Mix design of Polymer Modified Warm-mix Asphalt Mixture(RAP 50), and Hot Mix Asphalt Mixture(RAP 30) were produced and the properties of asphalt mixture such as Marshall Stability, ITS, Deformation Strength, TSR, and Dynamic Stability were compared between the two asphalt mixtures. RESULTS : The RAP 50 asphalt mixture showed superior or similar performances compared to the RAP 30 asphalt mixture in all the tests conducted. The results of the Marshall stability and dynamic stability in particular were 13,045N and 3,826 pass/mm, which were 11.37% and 76.7% greater than the RAP 30 asphalt mixture, which indicated that high plastic deformation resistance may be expected. CONCLUSIONS : The results obtained from laboratory tests on the two types of mixtures indicated that the use of polymer modified rejuvenator and warm-mix additive not only allows to increase the proportion of RAP but also improves its properties under lower temperature condition than RAP 30 asphalt mixture. Additionally, it was confirmed that plastic deformation resistance was high and moisture resistance and crack resistance were improved for a RAP 50 asphalt mixture.

Carbon 14 (14C) is radioactive isotope of carbon which emits beta ray with long half-life (5730±30 years). Since the 14C is significantly hazardous for human being, the appropriate process to treat 14C is necessary. From the nuclear power plant, the ion exchange resin, graphite, and activated carbon are the main source of 14C. During the effort to reduce the volume of those wastes, the 14C is inevitably occurred as carbon dioxide (CO2) form, so called 14CO2. Thus, the development of technology to permanently capture and safely dispose 14CO2 is required. In this presentation, we introduce the decommissioning technology ranging from 14CO2 capture to solidification. First, the new class of glass adsorbent is developed which can irreversibly capture CO2 even under mild conditions. This material promotes the dissolution of alkaline earth ions due to the unstable glass structure. Then, the physical and chemical optimization of glass adsorbent enhances the performance of CO2 capture. Further, room temperature geopolymeric solidification is also performed to safely dispose 14C without any potential release.