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81.
Qiang Wang Lei Shen Tong Xue Gao Cheng Cheng Zhi Huang Hong Jin Fan Yuan Ping Feng 《Advanced functional materials》2021,31(2):2002187
The {100} facet of single-crystalline TiO2(B) is an ideal platform for inserting Li ions, but it is hard to be obtained due to its high surface energy. Here, the single-crystalline TiO2(B) nanobelts from H2Ti3O7 with nearly 70% {100} facets exposed are synthesized, which significantly enhances Li-storage capacity. The first-principle calculations demonstrate an ab in-plane 2D diffusion through the exposed {100} facets. As a consequence, the nanobelts can significantly accommodate Li ions in LiTiO2 formula with specific capacity up to 335 mAh g−1, which is in good agreement with the electrochemical characterizations. Coating with conductive and protective poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate), the cut-off discharge voltage is as low as 0.5 V, leading to a capacity of 160.7 mAh g−1 after 1500 cycles with a retention rate of 66% at 1C. This work provides a practical strategy to increase the Li-ion capacity and cycle stability by tailoring the crystal orientation and nanostructures. 相似文献
82.
Simulating the psychological experience of human vision,a road extraction model based on the format tower is proposed to extract the road in the high resolution remote sensing image from the perspective of morphology.Firstly,based on the spectral and texture information,the suspected road targets are extracted by using segmentation technology.Then these targets are classified according to their reliability and extract the road targets for each category.Finally,three types of identified road information are verified and merged,and the continuous smooth road extraction results are obtained.Experiments on real high resolution images show that the results are consistent with the visual perception of the human eye,and the overall classification accuracy is higher,indicating that the algorithm is effective and feasible and has good use value. 相似文献
83.
2A12铝合金化学铣切加工工艺探讨 总被引:1,自引:0,他引:1
为了精确加工2Al2铝合金,探讨了化铣时间和温度对其化铣速率及表面粗糙度的影响,采用现代技术对化铣工件的力学性能进行了测试与分析.结果表明:延长非化铣部位保护胶固化时间并使保护部位向非加工面位移3~5 mm可很好地解决未化铣区域的腐蚀问题;随化铣时间的延长,化铣速率降低,且化铣温度与化铣速率呈现正相关性;化铣表面的粗糙度随化铣时间的延长而增加,随化铣温度的升高呈先减小后增加的趋势;化铣后材料的抗拉强度和屈服强度均有所提高. 相似文献
84.
采用突水系数法对象山煤矿北一采区11#煤层突水危险性进行了预测,结果显示,北一采区西北角、东南角属于相对安全区,突水系数0.06 MPa/m,北一采区北部B6孔附近为相对危险区,突水系数在0.1~0.119 MPa/m之间,其它区域处在临界区。该研究成果可为矿井防治水提供参考依据。 相似文献
85.
The low energy density of supercapacitors, especially supercapacitors based on aqueous electrolytes, is the main factor limiting their application, and the energy density is closely related to the operating potential window of the supercapacitor. The polymer electrolyte is the main contributor to the safe operation and good ion conductivity of the supercapacitor. In this study, a crosslinked quaternized poly(arylene ether sulfone) (PAES) membrane was prepared via crosslinking during membrane formation with a thermal-only treatment and applied in an electric double-layer capacitor (EDLC). The pre-prepared PAES membrane formed a polymer electrolyte with 1 mol/L Li2SO4 and was then fabricated into an EDLC single cell. The properties of both the membrane and ELDC were investigated. The preferred cPAES-N-0.2 polymer electrolyte showed an ionic conductivity of 1.18 mS/cm. The optimized EDLC exhibited a single-electrode gravimetric capacitance of 104.92 F/g at a current density of 1.0 A/g and a high operating potential window (1.5 V); it, thereby, achieved a high energy density of 8.20 W h/kg. The EDLC also exhibited excellent cycling properties over 3000 charge–discharge cycles. The crosslinked structures promoted the tensile strength and thermal stability of the PAES membranes; this was accompanied by a slight decrease in the ionic conductivity. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47759. 相似文献
86.
该文针对当前矿井炮掘巷道大断面掘进普遍存在掘进施工较慢的实际,结合公司实际情况,有针对性地提出了解决的办法。 相似文献
87.
某水泥厂钢丝胶带提升机(下文简称提升机)的驱动电机为三相异步电动机,其型号为:YE3-280M-4/90 kW,技术参数为:380 V/50 Hz/IP55/B3/F。在提升机空载试车过程中,电机三相电流出现不平衡现象,偏差达到了12%,实测三相电流数值分别为:60 A、65 A、75 A,其对应的三相电压分别为399 V、402 V、402 V。
针对上述现象,我们对产生三相电流不平衡的原因进行归纳,并对每种原因进行实验研究,最终得出了较为客观的结论。 相似文献
88.
89.
Tian Xiaoying Peng Hui Luo Xuguang Nie Shiyuan Zhou Feng Peng Xiaoyan 《International Journal of Control, Automation and Systems》2020,18(4):897-910
International Journal of Control, Automation and Systems - There is a class of typical nonlinear industrial process, which can be characterized by a first-order inertia plus pure delay model in an... 相似文献
90.
The Caputo and Caputo–Fabrizio derivative are applied to study a second‐grade nanofluid over a vertical plate. A comparative analysis is presented to study the unsteady free convection of a second‐grade nanofluid with a new time–space fractional heat conduction. The governing equations with mixed time–space fractional derivatives are non‐dimensionalized and solved numerically, and a comparison between the Caputo and the Caputo–Fabrizio models is made. It is found that the temperature is higher for the Caputo–Fabrizio fractional model than the Caputo model, but the higher velocity only exists near the vertical plate for the Caputo–Fabrizio model than the Caputo model. Moreover, the velocity for the Caputo model will exceed the Caputo–Fabrizio model as y evolves. 相似文献