Renewed interest in the reinforced carbon graphite composites has intrigued the community in the advanced materials fields. In this work, we present a simple carbon nanofibers reinforced carbon graphite composites synthetic method by incorporating mixture of coal tar pitch, synthetic graphite, pitch coke and the dispersion liquid of carbon nanofibers via liquid-phase mixing process. The impact of carbon nanofiber utilization on the microstructures and mechanical properties of carbon graphite composites are studied systematically. The covalent surface modification of carbon nanofibers effectively improves its microstructure and thereby promotes the carbon graphite composites’ dispersion behavior. We propose that a small amount of carbon nanofibers could promote the carbonization process of carbon graphite composites, facilitating the densification of carbon graphite composites and reducing the undesired open porosity. The amount of 0.7 wt % of carbon nanofiber concentration allows the enhancement of bend and compressive strength of carbon graphite composites up to 36.50 MPa and 60.46 MPa, increased by 167.9% and 146.9% compared with the pure carbon graphite composite, respectively. Our findings can be rationalized due to the improvement in the mechanical strength of carbon graphite composites could be attributed due to pull-out of carbon nanofibers from the matrix and bridging effect across the crack pores within the matrix.

In this study, graphene oxide (GO) was synthesized by the improved Hummers’ method. The degree of oxidation from graphite (Gi) to GO was determined through interlayer spacing calculated from X–ray diffraction. Besides, the effect of KMnO4: Gi ratios (X1), H2SO4 volume (X2), oxidation temperature (X3), oxidation time of stage 1 (X4), and oxidation time of stage 2 (X5) was screened by the Plackett–Burman model. The simultaneous impact of three factors that influenced the degree of oxidation (X1, X2, and X3) was studied by the Box–Behnken experimental model of response surface methodology to achieve suitable conditions for the GO synthesis process. The characterization of GO product was investigated via the modern analytical methods: X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, UV–Vis spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. Inaddition, the study was also carried out on a pilot scale for orientation in industrial application with the yield of 14 g/batch.

Supercross-linked polymers are widely used as carbon precursor materials due to their abundant carbon sources and low cost. In this paper, a supercross-linked polymer was prepared by the solvothermal method. The supercross-linked polymer as a precursor and the PPyC-800-A was synthesized by activating this with KOH. The microstructure, structure, and electrochemical performances of porous carbon PPyC-800-A were studied at different of temperature and carbon alkali ratio. According to the results, the porous carbon PPyC-800-1:2 is mainly composed of a stack of spherical particles with a high surface area of 1427.03 m2 g− 1, an average pore diameter of 2.32 nm, and a high specific capacitance of 217.7 F g− 1 at a current density of 1.0 A g− 1 in a 6 M KOH electrolyte. It’s retention rate is 97.58% after 5000 constant current charges and discharges. With a specific capacitance decay rate of 21.91 percent, an energy density of 11.96 Wh kg− 1, and a power density of 500.0 W kg− 1, the current density rises from 1.0 A g− 1 to 10.0 A g− 1, exhibiting remarkable electrochemical properties, cycling stability, and energy production performance This study contributes experimental ideas to the field of supercrosslinked polymer-derived carbon materials and energy storage.

A 9-year-old, intact female, Pungsan dog was referred for purulent vaginal discharge and depression. Abdominal radiographs revealed gas-filled and soft tissue opacity tubular structures in the mid to caudal abdomen. On ultrasonography, fluid-filled uterus and cervix accompanied by hyperechoic foci and reverberation artifacts were identified. Multiple hyperechoic foci were found within the uterine wall, indicating gas content. Escherichia coli was isolated from aerobic and anaerobic bacterial cultures. Radiological differential diagnosis of tubular shaped, dilated gas-filled structure, and gas in the wall of the structure should consider emphysematous pyometra with endometrial pneumatosis in intact female dogs with vulvar discharge.

본 논문은 가상 부동산 게임을 통한 가상토지 거래와 분할 거래를 위한 가상 경제 플랫폼을 제안한다. 이것은 실제 존재하는 지구 위의 땅이 아닌 가상공간에서 설계된 3차원 공간을 거래하고 소유하는 가상 경제 플랫폼 에 관하여 연구이다. 이를 위해 메타버스를 이용하여 실제 지구의 모습과 유사한 가상의 지구를 세분화시켜 구현했다. 또한 블록체인 기술을 이용한 가상화폐를 통해 거래의 신뢰성을 가질 수 있게 했다. 게임의 특징으 로는 다음과 같다. 가상공간의 콘텐츠 서비스를 위한 프로세스 기능을 단순화했다. 또한 서비스의 차별화를 통하여 사용자의 진입 장벽을 최소화했으며, 게임을 통해 부동산 분할 매매와 분할임대를 위한 프로세스를 제 안했다. 또한 가상부동산에 대한 수익모델을 통하여 가상 경제 플랫폼에 대한 개념을 제안했다. 본 논문은 메 타버스와 블록체인 기술을 활용하여 기존 경제적 가치 개념을 가상 경제 플랫폼으로 활용하는 연구 모델로 제안한다.

To determine the acceptability of Grain Utilization Value Added (GUVA) Japonica rice variety developed by the International Rice Research Institute (IRRI) and South Korea’s Rural Development Authority (RDA), home use tests were conducted in n=69 businesses that were using Japonica rice. In general, they were satisfied with the Japonica brands, because they provided them with the particulars needed in their Japanese and Korean dishes. According to them, the value and quality of the Japonica rice justify the price. However, the GUVA Japonica Rice variety’s positive ratings were significantly lower compared to the brands they were used to. This applied to both their overall and attributespecific evaluations. Among the attributes, size, shape, aroma, and stickiness received significantly lower ratings compared to the other Japonica varieties. For them, it was too small, too round, less aromatic, and less sticky which may lead to challenges in preparation consequently affecting the commercial acceptability of the dishes they offer. Even with this experience and perception, they were still willing to consider the GUVA Japonica Rice when it was available in the market. Using the Van Westendorp pricing model, GUVA Japonica yielded a price of PHP 51.00 (1.01 USD) which was competitive. These findings provide recommendations for measures that should be put in place so that value chain players can preserve and maintain quality until the rice reach the business market.

본 연구는 코팅 방법을 활용한 단결정 양극 소재 연구로서 Ni-rich계 다결정 양극 소재로 부터 단결정 양극 소재를 합 성하여 사이클 구동 시 양극 소재의 안정성을 향상시키고자 한다. 양극 소재에 LixCoO2와 LixSnO3 를 각각 코팅하여 이차입자 내부 혹은 외부에 코팅층이 형성된 양극 소재를 합성한 후 이를 소결하여 단결정 형성에 대한 영향을 비교 하였다. 입자 외부에 LixSnO3가 코팅되어 열처리 된 Ni0.8Co0.1Mn0.1O2(NCM811)의 경우 코팅 처리 없이 열처리된 양극 소재 보다 개선된 수명특성을 보였으나, 단결정화가 이뤄지지 않았다. 입자 내부에 LixCoO2 코팅층이 형성된 NCM811 을 열처리 한 결과 이차입자 내부에 형성된 Co 코팅층이 결정화되어 50회 사이클 후 기준 단결정 양극 소재의 방전용 량인 117.34 mAh·g-1 대비 129.11 mAh·g-1의 높은 방전용량을 나타내었고, 형상제어를 통해 이성적인 단결정화가 이뤄 졌다. 본 연구는 다결정체인 Ni-rich 양극소재의 단결정화에 대한 유요한 통찰력을 제공할 것으로 예상한다.

RCEP will have a significant impact on ASEAN, China and other contracting parties, significantly enhancing the cooperative levels between ASEAN and other essential economies in the region. It can develop the manufacturing industry in ASEAN and China with higher quality. First of all, this study used the Strengths (S), Weaknesses (W), Opportunities (O) and Threats (T) (SWOT) model to analyze the specific impacts of China’s participation in RCEP on the development of ASEAN’s manufacturing industry. Subsequently, strategic recommendations were put forward for the high-quality development of ASEAN’s manufacturing industry under the RCEP cooperation mechanism from four aspects of SO,WO, ST and WT. As the signing of RCEP provides an excellent development opportunity, the ASEAN member countries should carry out deeper cooperation with China; create new strengths for high-quality development of the manufacturing industry; erect a closer regional industrial chain and the supply chain; and promote the realization of a higher level of regional economic integration between ASEAN and China.

The surface of carbon films deposited with inverted plasma fireballs is analysed in this paper. Measurements were conducted with Raman spectroscopy, atomic force microscopy and nanoindentation. The latter was used to obtain Young’s modulus as well as Martens and Vickers hardness. The roughness of the film was measured by atomic force microscopy and its thickness was measured. It was shown with Raman spectroscopy that the films are homogeneous in terms of atomic composition and layer thickness over an area of about 125 × 125 mm. Furthermore, it was demonstrated that inverted plasma fireballs are a viable tool for obtaining homogeneous, large area carbon films with rapid growth and very little energy consumption. The obtained films show very low roughness.

Lead sulfide ( PbS ) nanocrystals anchored on nitrogen-doped multiwalled carbon nanotubes ( CNx ) have been synthesized employing an environmentally friendly and inexpensive wet chemistry process. CNx∕PbS composites have been examined by scanning electron microscopy, X-ray diffraction and Raman spectroscopy. Theorical ab initio calculations have been developed to determine the samples structural, morphological and optical properties to explain the experimental evidences. The PbS nanoparticles exhibit of 4 nm to 27 nm particle size with a face-centered cubic crystal structure and are homogeneously distributed along the carbon nanotubes. The nitrogen-doped CNTs acts as binding sites for the PbS clusters as ab initio theoretical study suggests.

Temperature is a crucial environmental factor for rice cultivation due to the climate change and can influence the rice growth and development. Therefore, the effect of temperature on plant growth characters was examined during the vegetative growth stage. Plants were grown under three different temperatures: 23°C/13°C for 18°C, 26°C/16°C for 21°C and 29°C/19°C for 24°C in the phytotron. The temperature was treated after transplanting and ended in early panicle initiation stage. Heading date of the two varieties were strongly affected by the temperature and were delayed in the 18°C. The plant height in the 18°C was 21 % shorter than the 21°C and 24°C and the tiller and leaf number were increased in the 18°C. All the growth rates of the characters were the slowest in 18°C. The stem dry weight was significantly increased in 18°C. Nitrogen content was increased in the leaves of 18°C whereas available phosphate and potassium contents was found to be increased in the stems of 21°C and 24°C. OsNRT2.1 was overexpressed in the leaves and stems of 18°C and OsNRT2.3a could be expressed in 18°C and 21°C temperatures whereas more expressed in 21°C. OsPT1 and OsPT6 could be expressed in the leaf of 18°C and 24°C but could be expressed more in the stem of 18°C. OsHAK1 and OsHAK5 could be overexpressed in the leaves and stems of 18°C. For hormone, OsCKX2 gene was found to be up regulated in the leaves of 18°C and OsIAA1 gene could expressed more in the stem of 24°C.

송충살이고치벌아과의 Aleiodes의 미기록종 4종(A. lipwigi, A. guidaae, A. subemarginatus, A. caprinus)을 국내 최초로 보고한다. 본 연구에 선 종의 동정을 위한 진단, 분포, 삽화 및 DNA 바코드 서열을 제공한다.

The research on dye-sensitized solar cells (DSSCs) is in the advanced stage today. The only concern observed so far has been regarding its stability and efficiency. Its power conversion efficiency can be increased by incorporating various methods and materials based on nanotechnology. Several attempts have been employed to develop advanced methods for eco-friendly, commercially viable, and sustainable DSSCs to minimize the energy crisis in the future. Photoanode is one of the essential components of DSSCs that can be modified using different nanostructures to enhance its efficiency. The TiO2 nanoparticlebased photoanode with gold and silver has proven to be potent materials for getting efficient DSSCs. The plasmonic and quantum confinement effects also play a vital role in efficiency enhancement. In this review, we discuss numerous attempts made by researchers in the last decade to modify the photoanode and their progress. We also look at different types of nanostructures, such as quantum dots, metal oxide doping, layered structures, nanocomposites, and thin film formation, that improve the efficiency of DSSCs. Several methods were reviewed to modify photoanodes to optimize electron transportation, light scattering, trapping power, surface area, and reduce charge recombination. The trend in the efficiency enhancement of DSSCs using TiO2, Au, ZnO, Ag, and graphene nanostructures-based photoanodes have been explored in great detail.

Metal-additive manufacturing techniques, such as selective laser sintering (SLS), are increasingly utilized for new biomaterials, such as cobalt-chrome (Co-Cr). In this study, Co-Cr gas-atomized powders are used as charge materials for the SLS process. The aim is to understand the consolidation of Co-Cr alloy powder and characterization of samples sintered using SLS under various conditions. The results clearly suggest that besides the matrix phase, the second phase, which is attributed to pores and oxidation particles, is observed in the sintered specimens. The as-built samples exhibit completely different microstructural features compared with the casting or wrought products reported in the literature. The microstructure reveals melt pools, which represent the characteristics of the scanning direction, in particular, or of the SLS conditions, in general. It also exposes extremely fine grain sizes inside the melt pools, resulting in an enhancement in the hardness of the as-built products. Thus, the hardness values of the samples prepared by SLS under all parameter conditions used in this study are evidently higher than those of the casting products.

Graphite felt is a felt-like porous material made of high-temperature carbonized polymers. It is widely used in electrode materials because of its good temperature resistance, corrosion resistance, large surface area and excellent electrical conductivity. In this paper, the surface functional group modification is of graphite felt electrodes (mainly nitrogen doping modification, nitrogen–sulfur or nitrogen–boron co-doping modification) and surface catalytic modification (metal/ion surface modification and metal oxide surface modification as Main). There are two main methods and research progresses to improve the performance of graphite felt electrodes, and the comprehensive performance of surface functional group-modified graphite felt electrodes and surface catalytically modified graphite felt electrodes are compared respectively. The results show that both surface functional group modification and surface catalytic modification can improve the comprehensive performance of graphite felt electrodes. In this paper, the future development direction of graphite felt activation modification is also prospected.

High-entropy alloys (HEAs) are attracting attention because of their excellent properties and functions; however, they are relatively expensive compared with commercial alloys. Therefore, various efforts have been made to reduce the cost of raw materials. In this study, MIM is attempted using coarse equiatomic CoCrFeMnNi HEA powders. The mixing ratio (powder:binder) for HEA feedstock preparation is explored using torque rheometer. The block-shaped green parts are fabricated through a metal injection molding process using feedstock. The thermal debinding conditions are explored by thermogravimetric analysis, and solvent and thermal debinding are performed. It is densified under various sintering conditions considering the melting point of the HEA. The final product, which contains a small amount of non-FCC phase, is manufactured at a sintering temperature of 1250oC.

We have been conducting a exoplanet search survey using Bohyunsan Observatory Echelle Spectrograph (BOES) for the last 18 years. We present the detection of exoplanet candidate in orbit around HD 18438 from high-precision radial velocity (RV) mesurements. The target was already reported in 2018 (Bang et al. 2018). They conclude that the RV variations with a period of 719 days are likely to be caused by the pulsations because the Lomb-Scargle periodogram of HIPPARCOS photometric and Hα EW variations for HD 18438 show peaks with periods close to that of RV variations and there were no correlations between bisectors and RV measurements. However, the data were not sufficient to reach a firm conclusion. We obtained more RV data for four years. The longer time baseline yields a more accurate determination with a revised period of 803 ± 5 days and the planetary origin of RV variations with a minimum planetary companion mass of 21 ± 1MJup. Our current estimate of the stellar parameters for HD 18438 makes it currently the largest star with a planetary companion.

Commercial carbon fiber cloth (CFC) is treated by the Joule-heating pyrolysis method in air to boost its capacitive performance on the premise of energy- and time-saving considerations. A thermoelectric coupling model suitable for the Jouleheating pyrolysis is successfully established based on the comparisons between the simulated temperatures and actually measured ones. The temperature field on CFC surface induced by the Joule heat presents a concentric-ellipse shape that the temperature in the core is the maximal and gradually decays outward. Increasing the direct current (DC) voltage which is applied to the CFC from 1.0 to 6.0 V, the core temperature on the CFC surface can be raised from 31 to 519 °C. The specific surface area and hydrophilicity of the as-prepared porous CFC are greatly improved compared with the pristine one. Electrochemical test shows that the optimal Joule-heating pyrolysis parameters falls at 5.0 V and 12.5 min, and the areal specific capacitance of as-obtained CFC-5.0-12.5 is about 80 folds that of the pristine CFC. In addition to the much shorter preparation time, all the characteristics including areal specific capacitance, rate performance, and electrical conductivity of the Joule-heating pyrolyzed CFC are superior to those of the electrical furnace pyrolyzed counterpart. The aqueous symmetrical supercapacitor made of CFC-5.0-12.5 electrodes exhibits considerable power and energy densities with respect to the previously reported carbon electrode-based supercapacitors. For conductive precursors, the Joule-heating pyrolysis can be an ideal substitute for the traditional electric furnace pyrolysis.