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1.
Cuspidine-based systems are used to control the crystallization in mold fluxes, which is enabled by CaF2 additions. However, excess CaF2 increases the corrosion of casting machines. Therefore, Na2O and K2O are added to the mold flux system to ensure an optimized crystallization and lubrication ability of the flux with the CaF2 content. This study investigated the effect of substituting Na2O with K2O on the volatilization of fluorine in a CaO–SiO2–CaF2-based slag system at high temperatures. The substitution of Na2O with K2O was performed at 5 mol% intervals. The volatilization was observed by thermogravimetric analysis under several isothermal conditions. The mass loss was measured at a heating rate of 5, 10, and 20 K/min. As the temperature increased, the volatilization of the mixed samples increased. The activation energy was calculated using the Flynn–Wall–Ozawa and Kissinger–Akahira–Sunose methods. A kinetic analysis of the volatilization of fluorine was conducted using the calculated parameters and several known kinetic models. Consequently, the volatilization of the Na-rich sample was controlled by chemical reactions and that of the K-rich sample was identified to be controlled by a phase-boundary-controlled reaction. These results suggest that the addition of mixed alkali oxide promote the volatilization during the early stages of the reaction. From the post-experimental composition analyses, the remaining Na and K in the samples suggested a different mechanism for the Na and K volatilization. The volatilization of Na increased with time, whereas K volatilized easily during the beginning of the reaction. 相似文献
2.
Deunsol Hwang Jong-Beom Seo Hun-Young Park Jisu Kim Kiwon Lim 《International journal of molecular sciences》2021,22(2)
While exercise training (ET) is an efficient strategy to manage obesity, it is recommended with a dietary plan to maximize the antiobesity functions owing to a compensational increase in energy intake. Capsiate is a notable bioactive compound for managing obesity owing to its capacity to increase energy expenditure. We aimed to examine whether the antiobesity effects of ET can be further enhanced by capsiate intake (CI) and determine its effects on resting energy expenditure and metabolic molecules. Mice were randomly divided into four groups (n = 8 per group) and fed high-fat diet. Mild-intensity treadmill ET was conducted five times/week; capsiate (10 mg/kg) was orally administered daily. After 8 weeks, resting metabolic rate and metabolic molecules were analyzed. ET with CI additively reduced the abdominal fat rate by 18% and solely upregulated beta-3-adrenoceptors in adipose tissue (p = 0.013) but did not affect the metabolic molecules in skeletal muscles. Surprisingly, CI without ET significantly increased the abdominal fat rate (p = 0.001) and reduced energy expenditure by 9%. Therefore, capsiate could be a candidate compound for maximizing the antiobesity effects of ET by upregulating beta-3-adrenoceptors in adipose tissue, but CI without ET may not be beneficial in managing obesity. 相似文献
3.
Bacteria with antibiotic-resistant could seriously threaten to human health, increasing the treatment cost for infections and negatively affecting treatment outcomes. Stress adaptation is one possible mechanism for the acquisition or enhancement of antibiotic resistance in bacteria as a result of cross-protection. In this study, the effects of acid, salt, and cold stress on the antibiotic resistance of Salmonella Enteritidis, Listeria monocytogenes, and Escherichia coli O157:H7 were investigated using the disc diffusion method. For S. Enteritidis, acidic growth conditions increased resistance to ciprofloxacin and erythromycin (p < .05), and addition of 4% NaCl to growth media decreased resistance to chloramphenicol (p < .05). Irrespective of pH and the NaCl concentration of the growth medium, refrigerated E. coli O157:H7 showed increased resistance to amoxycillin, ciprofloxacin, gentamicin, streptomycin, and erythromycin (p < .05). Acid-adapted L. monocytogenes showed decreased the resistance to amoxycillin, ampicillin, chloramphenicol, ciprofloxacin, erythromycin, gentamicin, streptomycin, and tetracycline (p < .05). In conclusion, prolonged exposure of foodborne pathogens to acid, salt, and cold stress alters their antibiotic resistance. However, the effect of acid, salt, and cold stress on bacterial antibiotic resistance depend on both the bacterial species and the specific antibiotic. Therefore, multiple factors need to be considered for a foodborne antimicrobial resistant risk assessment. 相似文献
4.
Dong Won Lee Dae Yeon Kim Ji Hyuck Hong Soo Hong Seo Young Chul Kye Hyo Hyun Ahn 《Microscopy research and technique》2019,82(1):12-17
Skin biopsy for AK diagnosis is usually performed on only a limited part of the whole lesion. Therefore, a clinical diagnosis is important. According to a study, there is no significant correlation between histopathological and clinical classification system. We examined the correlation between microscopic information and dermoscopic findings to deduce if dermoscopic information reflects histopathologic grade severity. Forty seven patients with histologically confirmed AK were enrolled and positive ratio of red pseudonetwork, rosette, red background and targetoid signs, white‐to‐yellow scale, white structureless area, and pigmentation from dermoscopic findings were investigated. Furthermore, viable epidermal thickness, vessel lumen dimensions, existence and thickness of ortho‐ and parakeratosis, degree of sola elastosis, flag sign existence, and Roewert‐Huber classification were measured as histologic findings. Red background did not show a significant correlation with vascular dimension or viable epidermal thickness. When targetoid sign was present, vascular dimension was significantly larger but showed no correlation with viable epidermal thickness, parakeratosis or orthokeratosis. Solar elastosis level was significantly higher when white‐to‐yellow scale was present. According to Spearman's correlation analysis, ortho/parakeratotic thickness showed correlations with each other. The negative correlation between viable epidermal thickness and vascular dimension was also shown. Roewert‐Huber histologic AK classification showed no correlation with any factors we checked. Factors considered to be characteristic features of AK in dermoscopy seemed unassociated with histologic AK classification and additional research is needed to determine degree of dysplasia of AK lesions using dermoscopy. 相似文献
5.
Suk-Young Song Soonil Pyo Sungchul Choi Hee Sang Oh Jung Hwa Seo Ji Hea Yu Ahreum Baek Yoon-Kyum Shin Hoo Young Lee Ja Young Choi Sung-Rae Cho 《International journal of molecular sciences》2021,22(7)
Hypoxic–ischemic encephalopathy (HIE) is a devastating neonatal brain condition caused by lack of oxygen and limited blood flow. Environmental enrichment (EE) is a classic paradigm with a complex stimulation of physical, cognitive, and social components. EE can exert neuroplasticity and neuroprotective effects in immature brains. However, the exact mechanism of EE on the chronic condition of HIE remains unclear. HIE was induced by a permanent ligation of the right carotid artery, followed by an 8% O2 hypoxic condition for 1 h. At 6 weeks of age, HIE mice were randomly assigned to either standard cages or EE cages. In the behavioral assessments, EE mice showed significantly improved motor performances in rotarod tests, ladder walking tests, and hanging wire tests, compared with HIE control mice. EE mice also significantly enhanced cognitive performances in Y-maze tests. Particularly, EE mice showed a significant increase in Cav 2.1 (P/Q type) and presynaptic proteins by molecular assessments, and a significant increase of Cav 2.1 in histological assessments of the cerebral cortex and hippocampus. These results indicate that EE can upregulate the expression of the Cav 2.1 channel and presynaptic proteins related to the synaptic vesicle cycle and neurotransmitter release, which may be responsible for motor and cognitive improvements in HIE. 相似文献
6.
Food Science and Biotechnology - Polyphenols are secondary metabolites produced in higher plants. They are known to possess various functional properties in the human body. Polyphenols also exhibit... 相似文献
7.
Inpainting has been continuously studied in the field of computer
vision. As artificial intelligence technology developed, deep learning technology
was introduced in inpainting research, helping to improve performance. Currently,
the input target of an inpainting algorithm using deep learning has been studied
from a single image to a video. However, deep learning-based inpainting technology for panoramic images has not been actively studied. We propose a 360-degree
panoramic image inpainting method using generative adversarial networks
(GANs). The proposed network inputs a 360-degree equirectangular format
panoramic image converts it into a cube map format, which has relatively little
distortion and uses it as a training network. Since the cube map format is used,
the correlation of the six sides of the cube map should be considered. Therefore,
all faces of the cube map are used as input for the whole discriminative network,
and each face of the cube map is used as input for the slice discriminative network
to determine the authenticity of the generated image. The proposed network performed qualitatively better than existing single-image inpainting algorithms and
baseline algorithms. 相似文献
8.
Seo Jiwan Yoo Karam Choi Seungjin Kim Yura Alex Han Sangyong 《Multimedia Tools and Applications》2019,78(20):28649-28663
Multimedia Tools and Applications - Unstructured text data is very important in many applications because it reflects the thought of the people who create this data. However, it is difficult to... 相似文献
9.
Kim Woo-Yong Seo Hyung-Tae Kim Soohyun Kim Kyung-Soo 《International Journal of Control, Automation and Systems》2020,18(4):824-833
International Journal of Control, Automation and Systems - This paper proposes a practical methodology for designing an optical image stabilization system controller that consists of a gyro signal... 相似文献
10.
Vladimir Pankov Dongyi Seo Sunghun Lee Eungsun Byon 《Materials Science & Technology》2020,36(5):564-574
ABSTRACTSpitting behaviour of four casted and powder metallurgy ingots used in the fabrication of NiCoCrAlY-type environmental protective coatings by electron beam physical vapour deposition was investigated and correlated with ingot microstructures and compositions. Spits found in the coatings mainly consisted of the Ni5Y phase precipitated in the β-NiAl matrix while their typical size exceeded 50?µm. Spitting was less pronounced for ingots having a higher Cr content, larger size of γ-Ni(Co, Cr) precipitates formed within β-NiAl grains and narrower transitional zone formed at the interface between molten and unmolten ingot regions and consisting of coarsened β grains. Large (above 100?µm) agglomerates of the Ni5Y phase detected below the zone were identified as the main spit precursors. 相似文献