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基于CPFD(Computational particle fluid dynamics)方法,对实验室前期研究的催化裂化管式分配器内的颗粒分配特性及内部流动特性进行了数值模拟,系统研究了输送风、松动风及分配器倾斜角度对颗粒分配不均匀指数的影响,并进一步考察了输送风和松动风对分配器各出口气体流量分布及内部气 固流动特性的影响。结果表明,增大输送风量、松动风量以及分配器的倾斜角度均可以降低颗粒分配不均匀指数,但改变松动风量的效果不如改变输送风量和倾斜角度显著。分配器倾斜角存在一个最优值时,颗粒分配均匀性最佳。输送风的增大会使得颗粒出料量最高的排料口的位置逐渐向分配器的末端移动,中间排料口所流出的气体流量占比增大,末端排料口排风量占比减小。引入松动风后,各出口的颗粒排料量更加接近,同时靠近末端排料口的气体流量占比明显增大。 相似文献
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《International Journal of Hydrogen Energy》2020,45(19):11167-11175
A new titanium (III) phosphite Ti2(HPO3)3, has been synthesized under hydrothermal conditions. The solid-state structure of this material was solved using single-crystal X-ray diffraction. The anionic inorganic skeleton has a three-dimensional structure, which is built up by TiO6 octahedral units linked together via bridging HPO3 pseudo pyramids, giving rise to tunnels along the three crystallographic axes. This new compound displays a high thermal stability limit of 625 °C. IR and Raman spectroscopies show the vibrational modes of the (HPO3)2−oxoanions. Electrochemical activity of this phase toward reversible insertion of Li ion was studied for the first time by galvanostatic charge-discharge measurements, an insertion host for reversible accommodation of Li+ was observed. 相似文献
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LI PAN WENTING YI DONGMIN LIANG YULONG ZHAO RANRAN WANG PINGYU WANG YOUJIE LI JIAXUAN XIN YUNFEI YAN SHUYANG XIE 《Biocell》2022,46(2):417-431
Tumor progression is usually characterized by proliferation, migration, and angiogenesis, which is essential for
supplying both nutrients and oxygen to the tumor cells. Therefore, targeting angiogenesis has been considered a
promising therapeutic strategy for cancer prevention and treatment. In the present study, we demonstrated that in
addition to suppressing lung cancer cell proliferation and migration in vitro, 10-hydroxycamptothecin (10-HCPT) is
also capable of inhibiting angiogenesis in vivo with a miR-181a-dependent manner. Mechanistically, by upregulating
miR-181a, which in turn downregulating FOXP1, 10-HCPT can inhibit the PI3K/Akt/ERK signaling pathwaymediated angiogenesis. Furthermore, reduced levels of miR-181a have been found in both lung cancer cell lines and
xenograft with concurrently elevated levels of FOXP1, VEGF, bFGF, and HDGF. Consistent with the findings from
the in vitro experiments, miR-181a impairs neovascularization in our xenograft model. In summary, our findings have
not only established the anti-oncogenic role of miR-181a in lung cancer angiogenesis but also suggest that 10-HCPT
could be a potential therapeutic reagent for lung cancer treatment. 相似文献
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Yaya Wang Wei Gao 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(8):987-993
Fuel quality, especially biodiesel, is highly dependent on its water content, and the major sources of water in the fuel relate to the transportation, production, and storage processes. In this present contribution, the multilayer perceptron artificial neural network (MLP-ANN) was applied to predict the water content of biodiesel and diesel blend in terms of temperature and composition. The proposed algorithm was trained and tested by utilizing 400 experimental data points which were extracted from the literature. Based on the results, the MLP-ANN model has great ability to estimate the water content of biodiesel and diesel blend. The R-squared (R2), root mean square error, average absolute relative deviation, and a?bsolute deviation parameters for the total data set are obtained, respectively, as 0.99784, 123919.1172, 3.3632, and 1.17%, which indicate the effective performance suggested by ANN. As the computational study is cheaper and easier than the experimental study, the developed software could be considered as an alternative for laboratory study, and the environmental effect of biodiesel and produced undesired product after biodiesel combustion which is directly related to the water content of biodiesel is estimable with the information released in this study. 相似文献
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Haibin Sun Xue Guo Jiao Li Guochang Li Zanzhong Yang Hao Ding Weilu Yan Shuai Qi Peng Wang Youjie Song 《Ceramics International》2019,45(1):622-626
In order to clarify the effect of grain size on the electrical performance of BaZr0.1Ce0.7Y0.1Yb0.1O3-δ (BZCYYb) solid electrolytes with addition of NiO, microcrystalline (~1.5?µm) and ultrafine-grained (~280?nm) BZCYYb electrolytes (with 1?wt% NiO) were fabricated by the conventional and two-step sintering method, respectively. The results show that compared with microcrystalline electrolytes, the ultrafine-grained electrolytes have similar grain-interior conductivities, but much lower grain-boundary conductivities, illustrating that the grain boundary is not conducive for ionic transport. As a result, the electrical conductivity of microcrystalline electrolytes (1.9?×?10?2 S?cm?1 at 600?°C in wet air) is higher than that of ultrafine-grained electrolytes (1.1?×?10?2 S?cm?1 at 600?°C in wet air). In addition, the OCV (open-circuit voltage) values of electrolyte-supported single cells show that the undesired electronic conduction exists in the electrolytes due to the BaY2NiO5 impurity formed by the reaction of NiO and BZCYYb. The ultrafine-grained electrolytes show lower OCV values than that of microcrystalline ones, due to the prolonged electronic transport paths. Therefore, large-grained or grain boundary-free microstructure are necessary for improving the electrical performance of BZCYYb electrolytes. 相似文献
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Multimedia Tools and Applications - Semantic segmentation of ocean remote sensing images classifies each pixel in the image according to the ocean background and island type, and is an important... 相似文献