This study was conducted to investigate the effects of feeding DDGS and full-fat soybean in the finishing diet on the performance, carcass characteristics and unsaturated fatty acid composition of Hanwoo steers. Thirty Hanwoo steers (average age, 26.4 months; weight, 756.69 kg) were assigned into Control (no additive), DS (DDGS supplemented) and FS (full-fat soybean supplemented). The feeding rate of DDGS and full-fat soybean was set at 10% and 5% in the finishing diet, respectively, and the in vivo trial was conducted for 122 days. The final body weight was 779.81, 774.20 and 791.95 kg for Control, DS and FS, respectively, and the average daily gain was not different among treatments. The feed conversion ratio was lower in FS compared to Control. Carcass cold carcass weight, backfat thickness, M. longissimus dorsi area and marbling scores were not different among treatments, and moisture, crude protein, and crude fat content in carcass were not different. The melting point of sirloin ranged from 25 to 26℃ among treatments. The saturated fatty acid, C18:0, was lower in the FS than in Control. C18:1, the main unsaturated fatty acid (UFA) in carcasses, did not show any difference among treatments, but C18:2 was higher in DS than in Control. Total UFAs were higher in the FS than in Control. Based on the above results, DDGS feeding was effective in improving feed conversion ratio and C18:2 content, and full-fat soybean feeding was effective in improving feed conversion ratio and increasing UFA content.
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.
To improve the lithium-ion battery performance and stability, a conducting polymer, which can simultaneously serve as both a conductive additive and a binder, is introduced into the anode. Water-soluble polyaniline:polystyrene sulfonate (PANI:PSS) can be successfully prepared through chemical oxidative polymerization, and their chemical/mechanical properties are adjusted by varying the molecular weight of PSS. As a conductive additive, the PANI with a conjugated double bond structure is introduced between active materials or between the active material and the current collector to provide fast and short electrical pathways. As a binder, the PSS prevents short circuits through strong π‒π stacking interaction with active material, and it exhibits superior adhesion to the current collector, thereby ensuring the maintenance of stable mechanical properties, even under high-speed charging/discharging conditions. Based on the synergistic effect of the intrinsic properties of PANI and PSS, it is confirmed that the anode with PANI:PSS introduced as a binder has about 1.8 times higher bonding strength (0.4 kgf/20 mm) compared to conventional binders. Moreover, since active materials can be additionally added in place of the generally added conductive additives, the total cell capacity increased by about 12.0%, and improved stability is shown with a capacity retention rate of 99.3% even after 200 cycles at a current rate of 0.2 C.
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.
In additive manufacturing, the flowability of feedstock particles determines the quality of the parts that are affected by different parameters, including the chemistry and morphology of the powders and particle size distribution. In this study, the microstructures and flowabilities of gas-atomized heat-resistant alloys for additive manufacturing applications are investigated. A KHR45A alloy powder with a composition of Fe-30Cr-40Mn-1.8Nb (wt.%) is fabricated using gas atomization process. The microstructure and effect of powder chemistry and morphology on the flow behavior are investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and revolution powder analysis. The results reveal the formation of spherical particles composed of single-phase FCC dendritic structures after gas atomization. SEM observations show variations in the microstructures of the powder particles with different size distributions. Elemental distribution maps, line scans, and high-resolution XPS results indicate the presence of a Si-rich oxide accompanied by Fe, Cr, and Nb metal oxides in the outer layer of the powders. The flowability behavior is found to be induced by the particle size distribution, which can be attributed to the interparticle interactions and friction of particles with different sizes.
This study examined the effects of micro- (crystallinity) and macro (orientation)-crystalline properties of graphite on the initial efficiency, discharge capacity, and rate performance of anodic materials. Needle coke and regular coke were selected as raw materials and pulverized to 2–25 μm to determine the effects of crystalline properties on particle shape after pulverization. Needle coke with outstanding crystallinity had high initial efficiency, and smaller particles with larger specific surface areas saw increased irreversible capacity due to the formation of SEI layers. Because of cavities existing between crystals, the poorer the crystalline properties were, the greater the capacity of the lithium ions increased. As such, regular coke had a 30 mAh/g higher discharge capacity than that of needle coke. Rate performance was more affected by particle size than by crystalline structure, and was the highest at a particle distribution of 10–15 μm.
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.
Continuous synthesis of high-crystalline carbon nanotubes (CNTs) is achieved by reconfiguring the injection part in the reactor that is used in the floating catalyst chemical vapor deposition (FC-CVD) process. The degree of gas mixing is divided into three cases by adjusting the configuration of the injection part: Case 1: most-delayed gas mixing (reference experiment), Case 2: earlier gas mixing than Case 1, Case 3: earliest gas mixing. The optimal synthesis condition is obtained using design of experiment (DOE) in the design of Case 1, and then is applied to the other cases to compare the synthesis results. In all cases, the experiments are performed by varying the timing of gas mixing while keeping the synthesis conditions constant. Production rate (Case 1: 0.63 mg/min, Case 2: 0.68 mg/min, Case 3: 1.29 mg/min) and carbon content (Case 1: 39.6 wt%, Case 2: 57.1 wt%, Case 3: 71.6 wt%) increase as the gas-mixing level increases. The amount of by-products decreases stepwise as the gas-mixing level increases. The IG/ID ratio increases by a factor of 7 from 10.3 (Case 1) to 71.7 (Case 3) as the gas-mixing level increases; a high ratio indicates high-crystalline CNTs. The radial breathing mode (RBM) peak of Raman spectrograph is the narrowest and sharpest in Case 3; this result suggests that the diameter of the synthesized CNTs is the most uniform in Case 3. This study demonstrates the importance of configuration of the injection part of the reactor for CNT synthesis using FC-CVD.