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E.?N.?SmirnovEmail author A.?N.?Smirnov V.?A.?Sklyar V.?A.?Belevitin S.?P.?Eron’ko R.?E.?Pivovarov 《Steel in Translation》2018,48(6):381-387
Research on expanding the product range and minimizing the energy costs at a linear medium-bar mill with three-high roughing stands is discussed. The possibility of controlling the mechanical properties of the product by decreasing the initial rolling temperature is considered. Despite the improvement in mechanical properties, decrease in the initial rolling temperature in the range 900–950°C is accompanied by increase in current load at the primary drive and decrease in dimensional precision of the product. 相似文献
994.
S. I. Vecherskii M. A. Konopel’ko B. D. Antonov N. N. Batalov M. A. Zvezdkin I. V. Zvezdkina 《Russian Metallurgy (Metally)》2018,2018(2):149-154
Oxides LaCoO3 – δ + (z/2) Li2O (0 ≤ z ≤ 0.15) are synthesized to determine the boundaries of changing the electrophysical properties of LaCoO3 – δ due to its in situ lithiation in the (Li0.62K0.38)2CO3 eutectic melt. A perovskite-like solid solution (La1 – xLi x )(Li x Co1 – x)O3 – δ, where x = z/(z + 2), is found to form as a result of Li doping. The region of existence of the solution does not exceed 2x = 0.072. At a higher concentration of Li, LiCoO2 forms along with the perovskite-like phase. At the operating temperature of the carbonate fuel cell (T = 920 K), the single-phase samples have metallic conduction and positive thermopower. The electrical conductivity of the Li-doped samples decreases as compared to that of LaCoO3 – δ by no more than 1.5 times and varies from 3.2 × 104 to 3.8 × 104 S/m. 相似文献
995.
Wojciech Wojnowski Tomasz Majchrzak Piotr Szweda Tomasz Dymerski Jacek Gębicki Jacek Namieśnik 《Food Analytical Methods》2018,11(8):2085-2092
The use of proton transfer reaction mass spectrometry (PTR-MS) for freshness classification of chicken and turkey meat samples was investigated. A number of volatile organic compounds (VOCs) were selected based on the correlation (>?95%) of their concentration during storage at 4 °C over a period of 5 days with the results of the microbial analysis. In order to verify if the selected compounds are not sample-specific, a number of samples sourced from various retailers were classified using the concentration of these compounds in the samples’ volatile fraction as input variables. The classification was performed using the support vector machines (SVM) supervised pattern recognition algorithm. It was concluded that it is possible to evaluate the shelf life of meat samples obtained from the same source based on the results of a prior analysis. The PTR-MS fingerprint approach might supplement the currently used methods of shelf life evaluation of poultry due to the short time and non-destructive nature of measurement and ease of quantitative analysis. 相似文献
996.
Ana María Zrate Christian Espinosa-Bustos Simn Guerrero Anglica Fierro Felipe Oyarzún-Ampuero Andrew F. G. Quest Lucia Di Marcotullio Elena Loricchio Miriam Caimano Andrea Calcaterra Matías Gonzlez-Quiroz Adam Aguirre Jaime Melndez Cristian O. Salas 《International journal of molecular sciences》2021,22(16)
The Smoothened (SMO) receptor is the most druggable target in the Hedgehog (HH) pathway for anticancer compounds. However, SMO antagonists such as vismodegib rapidly develop drug resistance. In this study, new SMO antagonists having the versatile purine ring as a scaffold were designed, synthesised, and biologically tested to provide an insight to their mechanism of action. Compound 4s was the most active and the best inhibitor of cell growth and selectively cytotoxic to cancer cells. 4s induced cell cycle arrest, apoptosis, a reduction in colony formation and downregulation of PTCH and GLI1 expression. BODIPY-cyclopamine displacement assays confirmed 4s is a SMO antagonist. In vivo, 4s strongly inhibited tumour relapse and metastasis of melanoma cells in mice. In vitro, 4s was more efficient than vismodegib to induce apoptosis in human cancer cells and that might be attributed to its dual ability to function as a SMO antagonist and apoptosis inducer. 相似文献
997.
Adam Wichniak Aleksander Kania Mariusz Siemiski Wiesaw Jerzy Cubaa 《International journal of molecular sciences》2021,22(16)
Melatonin is registered to treat circadian rhythm sleep–wake disorders and insomnia in patients aged 55 years and over. The essential role of the circadian sleep rhythm in the deterioration of sleep quality during COVID-19 confinement and the lack of an adverse effect of melatonin on respiratory drive indicate that melatonin has the potential to be a recommended treatment for sleep disturbances related to COVID-19. This review article describes the effects of melatonin additional to its sleep-related effects, which make this drug an attractive therapeutic option for treating patients with COVID-19. The preclinical data suggest that melatonin may inhibit COVID-19 progression. It may lower the risk of the entrance of the SARS-CoV-2 virus into cells, reduce uncontrolled hyper-inflammation and the activation of immune cells, limit the damage of tissues and multiorgan failure due to the action of free radicals, and reduce ventilator-induced lung injury and the risk of disability resulting from fibrotic changes within the lungs. Melatonin may also increase the efficacy of COVID-19 vaccination. The high safety profile of melatonin and its potential anti-SARS-CoV-2 effects make this molecule a preferable drug for treating sleep disturbances in COVID-19 patients. However, randomized clinical trials are needed to verify the clinical usefulness of melatonin in the treatment of COVID-19. 相似文献
998.
Adam Brzezinski Lin Li Xianli Qiao Jun Ni 《The International Journal of Advanced Manufacturing Technology》2009,45(5-6):470-480
To facilitate the implementation of machine monitoring algorithms on the shop floor, signal processing and decision-making strategies must be developed, which account for the difficulties associated with monitoring a machine in an industrial environment. Therefore, this paper focuses on introducing a new method for dresser contact detection, which takes into account sensor and data acquisition system costs, computational limitations of an embedded detection system, and noise robustness issues associated with shop floor implementation. This paper also discusses the way in which the monitoring algorithm directly interfaces with the machine control in real time in order to ensure that system faults are avoided. Furthermore, the new algorithm is compared with more traditional methods for change detection by applying each algorithm to the signal output from a dresser horsepower sensor. In an industrial application, the new algorithm is shown to provide zero missed detections, zero false alarms, and a sufficiently fast response time. 相似文献
999.
Hayrettin Düzcüko?lu 《Tribology International》2009,42(8):1146-1153
In polyamide based gears, thermal damage of the gear tooth surfaces occurs during gear meshing due to accumulated heat in the tooth body. In the experimental study reported in this paper, polyamide gear teeth have been modified in order to distribute the generated heat on the tooth surface by means of drilled cooling holes at different locations on the gear tooth body. The main aims of this paper were to study the effect of cooling holes on the accumulated heat on the tooth surface and on the measured wear. It was shown that the drilled cooling holes on the tooth body decreased the tooth surface temperature and led to an increase in the load carry capacity and improved wear resistance. Geometrically modified gears have showed an improved service life and a decreased surface temperature. 相似文献
1000.
Gaussian filtering is a basic operation commonly used in numerous image and volume processing algorithms. It is, therefore, desirable to perform it as efficiently as possible. Over the last decade CPUs have been successfully extended with several SIMD (Single Instruction Multiple Data) extensions, such as MMX, 3DNow!, and SSE series. In this paper we introduce a new technique for Gaussian filtering of volume data sets—the extended volume—together with its SIMD implementation using the SSE technology. We further introduce a SIMD optimized recursive IIR implementation of the Gaussian filter, and finally, we parallelize the SSE versions with the help of OpenMP (Open Multi‐Processing). Experimental evaluation indicates that the SIMD implementation can significantly speed up both versions of the Gaussian filtering and that the non‐recursive extended volume version is faster than the recursive IIR one for small widths of the Gaussian filter. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献