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71.
Yue Gao Miao-miao Zhang Xiao-peng Guo Wen-jian Li Dong Lu 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2020,95(5):1290-1297
Toxicity caused by the accumulation of butanol in fermentation media is an important factor limiting the concentration of butanol. There is currently no systematic research in place investigating the butanol tolerance mechanism of bacteria such as Clostridium acetobutylicum, which adapts to butanol stress and regulates its growth and metabolism. Here, research results related to the butanol tolerance of C. acetobutylicum are reviewed to understand the molecular basis of changes in butanol-tolerant strains. Organic solvent-tolerant bacteria play an important role in the fields of biofuel production, enzyme preparation and bioremediation. An analysis of limitations of the application of organic solvent-tolerant bacteria has revealed that future research should focus on combining the microbial tolerance phenotype with specific utilization to achieve an optimal balance between organic solvent tolerance and production. This review serves as a reference for the improvement and engineering of strains that tolerate organic solvents. © 2019 Society of Chemical Industry 相似文献
72.
Xiao-Guang Yue Guang Zhang Qu Wu Fei Li Xian-Feng Chen Gao-Feng Ren Mei Li 《稀有金属(英文版)》2015,(2):125-132
In order to predict the wearing of stellite alloys,the related methods of rare metals data processing were discussed. The method of opposite degree(OD) algorithm was put forward to predict the wearing of stellite alloys.OD algorithm is based on prior numerical data, posterior numerical data and the opposite degree between numerical forecast data. To compare the performance of predicted results based on different algorithms, the back propagation(BP) and radial basis function(RBF) neural network methods were introduced. Predicted results show that the relative error of OD algorithm is smaller than those of BP and RBF neural network methods. OD algorithm is an effective method to predict the wearing of stellite alloys and it can be applied in practice. 相似文献
73.
A novel AlSiMgAl2O4Al2O3 composite brick was prepared and evaluated in the low vessel of an RH (the initials of Ruhrstahl and Hereaeus) secondary refining furnace; it was characterized by X-ray diffraction, scanning electron microscopy, and energy-dispersive spectroscopy. The results show that after use, the AlSiMgAl2O4Al2O3 composite has a functional gradient with an erosion zone–reinforced zone–original zone phase distribution, in which the phases in the erosion zone (0–1.8?cm) are a Mg-hercynite spinel solid solution, α-Al2O3, and minor amount of Al3Fe5O12. Furthermore, the phases in the reinforced zone (1.8–5.0?cm) are γ-AlON, 21RSiAlON, SiC, Mg0.388Al2.408O4, and α-Al2O3; i.e., the Al and Si in the composite are completely converted into non-oxide reinforced phases. Finally, the phases in the original zone (>5.0?cm) show no change. The reaction mechanism is as follows. During operation, a Mg-hercynite spinel solid solution is formed in the erosion zone due to a reaction between MgAl2O4 and FeO from a refinery operation. Therefore, the slag erosion of the material is improved. The Al and Si metals undergo active oxidation, and 21RSiAlON flakes are subsequently formed from the products of the metastable Al2O(g), SiO(g), and N2(g) in the ambient. The γ-AlON is formed by a carbothermal reduction nitridation of the α-Al2O3 and residual active carbon from the resin binder. The 21RSiAlON and γ-AlON reinforce the composite brick and improve its high temperature performance accordingly. Its service life is 110% that of the magnesia-chrome bricks used in the same period. The reaction model was also established. 相似文献
74.
Zhao Chao-Yue Jia Rui-Sheng Liu Qing-Ming Liu Xiao-Ying Sun Hong-Mei Zhang Xing-Li 《Multimedia Tools and Applications》2021,80(1):263-277
Multimedia Tools and Applications - To address the problems of insufficient detail extraction and long training time in the super-resolution reconstruction of chest X-ray images, a method of chest... 相似文献
75.
Jialin Sun Jun Zhao Xiuying Ni Feng Gong Zuoli Li 《Journal of the European Ceramic Society》2018,38(9):3096-3103
This work investigates the critical roles of two-step sintering (TSS) and laminated structure on the sintering behavior and mechanical properties of functionally graded WC-TiC-Al2O3 nanostructured composite materials doped with Cr3C2/VC. Results show that excellent mechanical properties are achieved for tailored TSS conditions with a hardness of 27.91?±?2.3?GPa and a flexural strength of 1423.3?±?23.5?MPa. The desirable mechanical properties are attributed to the suppressed grain growth without densification deterioration. TSS is more effective in facilitating the favorable dispersion of secondary phase toughening nano-particulates in a WC matrix than conventional sintering (CS). Cr3C2/VC dopant plays an important role in maximizing and shifting the temperature range of the kinetic window for WC-Al2O3 composites. Al2O3 crack deflection, transgranular Al2O3, microcracking, WC crack bridging and plate-like WC crack deflection are the major toughening mechanisms. Residual surface compressive stress induced by the graded structure is also an appreciated contribution to the improvement of mechanical properties. 相似文献
76.
Correlation between instrumental texture and colour quality attributes with sensory analysis of selected cheeses as affected by fat contents
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A. Półtorak J. Wyrwisz M. Moczkowska M. Marcinkowska‐Lesiak A. Stelmasiak U. Ulanicka M. Zalewska A. Wierzbicka Da‐Wen Sun 《International Journal of Food Science & Technology》2015,50(4):999-1008
This study evaluated several physical and sensory parameters of different types of cheese available in the Polish market. The measurements of textural properties were conducted in an Instron universal testing machine, while the colour properties of cheeses were measured using a Minolta chromameter. The chemical composition was determined by means of the near‐infrared spectroscopy (NIRs). Moreover, a trained sensory panel was invited to assess the cheese texture‐related properties. Generally, cheeses with reduced fat content were characterised by higher hardness, adhesiveness, cohesiveness and elasticity. Texture‐related parameters of cheese with canola oil were comparable to that of most of full‐fat cheeses. The correlation analysis between physical and sensory attributes related to cheese textural properties indicated the potential applications of TPA, shear and penetration tests (r = 0.766, r = 0.75 and r = 0.765, respectively) for the evaluation of sensory properties related to the hardness. Meanwhile, the elasticity of cheese obtained from sensory evaluation was strongly correlated with the elasticity determined from the shear test (r = 0.722) and moderately correlated with the elasticity from penetration test (r = 0.588), indicating a need to refine the method of penetration test. In addition, cheeses exhibited higher meltability during convection heating at 230 °C than microwave heating. The values of meltability for cheese with reduced fat content were lower than those of full‐fat cheese. 相似文献
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78.
Neural Processing Letters - The beta processes (BP) is a powerful nonparametric tool in feature learning, which is often used as the prior of Bernoulli process for choosing features from a feature... 相似文献
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