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71.
72.
Xiao Junbing Yan Hongjie Liu Liu Möller Felix Hu Zhiwen Unger Sebastian 《Metallurgical and Materials Transactions B》2019,50(6):3002-3011
Metallurgical and Materials Transactions B - Spout height is a widely used parameter to quantitatively analyze the performance of the submerged gas injection in industrial applications. However,... 相似文献
73.
Wireless Personal Communications - The advance of wireless and mobile communications and networking technologies enables networked nodes to transmit and receive data in ad hoc manners without... 相似文献
74.
Wireless Personal Communications - In this paper, we investigate the secrecy outage performance of the decode-and-forward cognitive relay network with the existence of the co-channel interference,... 相似文献
75.
Bin Zhang Xuesong Jiang Fei Shen Xueming He Yong Fang Qiuhui Hu 《International Journal of Food Science & Technology》2021,56(6):2588-2595
This work intends to develop an online experimental system for screening of deoxynivalenol (DON) contamination in whole wheat meals by visible/near-infrared (Vis/NIR) spectroscopy and computer vision coupling technology. Spectral and image information of samples with various DON levels was collected at speed of 0.15 m s−1 on a conveyor belt. The two-type data were then integrated and subjected to chemometric analysis. Discriminant analysis showed that samples could be classified by setting 1000 μg kg−1 as the cut-off value. The best correct classified rate obtained in prediction was 93.55% based on fusion of spectral and image features, with reduced prediction uncertainty as compared to single feature. However, quantification of DON by quantitative analysis was not successful due to poor model performance. These results indicate that, although not accurate enough to provide conclusive result, this coupling technology could be adopted for rapid screening of DON contamination in cereals and feeds during processing. 相似文献
76.
Sarengaowa Wenzhong Hu Ke Feng Zhilong Xiu Aili Jiang Ying Lao 《International Journal of Food Science & Technology》2019,54(12):3128-3137
In this study, the inhibition of an alginate-based edible coating (EC) containing thyme oil (0.05%, 0.35% and 0.65%) was evaluated against Listeria monocytogenes, Salmonella Typhimurium, Staphylococcus aureus and Escherichia coli O157:H7 inoculated onto fresh-cut apples. To investigate the antibacterial mechanism of thyme oil, the constituent compounds of that were analysed by gas chromatography-mass spectrometry (GC-MS), and the cellular damage of pathogens was observed by scanning electron microscopy (SEM). Results showed that alginate-based EC containing thyme oil effectively inhibited the growth of pathogens on fresh-cut apples. GC-MS analysis revealed thymol (47.23%) as the major compounds in thyme oil. SEM showed that the cell membrane of foodborne pathogens was damaged by thyme oil, causing their inactivation. Treatment with alginate-based EC containing 0.05% thyme oil preserved the sensory characteristics of fresh-cut apples. Therefore, using alginate-based EC with thyme oil may represent a potential approach to preserve and enhance the safety of fresh-cut apples. 相似文献
77.
某型阵列天线属于机载设备,在做完随机振动试验后,第2个天线单元的一个辐射板被振裂.为了快速找到断裂原因,改进天线结构,利用有限元仿真软件ANSYS Workbench进行随机振动仿真分析.分析结果表明:原天线单元辐射板根部圆角太小,产生较大应力集中,最大3σ应力为102.74 MPa,超过材料疲劳极限应力87 MPa;改进后的天线结构,最大3σ应力降低24.2%,其数值为77.85 MPa,小于疲劳极限应力,满足设计要求.最终,改进后的天线结构顺利通过振动试验,有效验证了仿真分析与结构改进的合理性. 相似文献
78.
LiCuNb3O9 has been reported newly a colossal permittivity (CP) perovskite, in which the B-site NbO6 octahedra play a bridging role in the polaron hopping. However, how the A-site modification affects the origin of the polarons and further the CP behaviours remains unexplored. To this end, A-site Ca2+ was incorporated to form Li1-xCaxCuNb3O9, and the local states, dielectric relaxations and conduction behaviours were comprehensively studied. The substitution induces the polyvalent Cu cations, i.e. Cu+/Cu2+/Cu3+. Bond valence sum calculations imply that Cu2+ and Cu3+ are underbonded, and Cu+ is overbonded, while B-site Nb5+ shows slightly different with theoretical pentavalence. All the compositions exhibit a similarly room-temperature CP response, but present two dielectric relaxations, i.e. TR1:170–300 K and TR2:260–400 K. Comprehensive investigations on universal dielectric response and bulk dc conductivity indicate that the TR1 follows the variable-range-hopping where the electron hopping between the mixed Cu+/Cu2+, while TR2 contributes from the Cu3+ nearest neighbor hopping. 相似文献
79.
Fangjun Zhu You Shi Guorong Hu Zhongdong Peng Yanbing Cao Qian Sun Zhichen Xue Yinjia Zhang Ke Du 《Ceramics International》2021,47(3):3070-3078
Titanium and boron are simultaneously introduced into LiNi0.8Co0.1Mn0.1O2 to improve the structural stability and electrochemical performance of the material. X-ray diffraction studies reveal that Ti4+ ion replaces Li+ ion and reduces the cation mixing; B3+ ion enters the tetrahedron of the transition metal layers and enlarges the distance of the [LiO6] layers. The co-doped sample has spherical secondary particles with elongated and enlarged primary particles, in which Ti and B elements distribute uniformly. Electrochemical studies reveal the co-doped sample has improved rate performance (183.1 mAh·g-1 at 1 C and 155.5 mAh·g-1 at 10 C) and cycle stability (capacity retention of 94.7% after 100 cycles at 1 C). EIS and CV disclose that Ti and B co-doping reduces charge transfer impedance and suppresses phase change of LiNi0.8Co0.1Mn0.1O2. 相似文献
80.
Min Ye Feng Hu Deshuang Yu Silin Han Linlin Li Shengjie Peng 《Ceramics International》2021,47(13):18424-18432
In high demand is developing trifunctional electrocatalysts to simultaneously drive hydrogen evolution reaction (HER) and oxygen evolution/reduction reaction (OER/ORR) for metal-air batteries and water splitting. Here we develop the carbon nanotubes (CNTs)-grafted FeC/MnO2 nanocomposite catalyst by carbonizing FeMn metal-organic frameworks. The synergistic effect between FeC and MnO2 dominantly contributes the ORR, OER, and HER. The transition metal-mediated growth of CNTs by an in-situ catalysis mechanism enables high electrical conductivity, abundant active sites, as well as efficient reaction pathways. The optimized chemical composite and unique hierarchical structure endow the FeC/MnO2 with low overpotentials for multiply electrochemical reactions. Consequently, the composite catalyst successfully serves as the bifunctional electrode for water splitting with a voltage of 1.66 V at 10 mA cm?2 as well as the cathode for all-solid-state metal-air battery with Pt/C-comparable performance. The advanced transition metal composite presented in this work provides the guidance for rationally developing trifunctional electrocatalysts for efficient integrated energy conversion systems. 相似文献