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为满足现代日益增长的健康减肥的需求,文中以ARM7为微处理器设计了一款嵌入式电子产品计步器,运用液晶图形化显示技术,大容量信息存储,测量和控制数据处理技术,网络通信技术等,加入嵌入式系统的应用,移植了uClinux实时操作系统,实现了仪表的智能化、信息化和网络化。实践证明其满足了实用性和可靠性的要求。 相似文献
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Measurement of 232Th (n,γ) cross section at the CSNS Back-n facility in the unresolved resonance region from 4 keV to 100 keV 下载免费PDF全文
Bing Jiang 《中国物理 B》2022,31(6):60101-060101
The neutron capture cross section of 232Th was measured at the neutron time-of-flight facility Back-n of China Spallation Neutron Source (CSNS) for the first time. The measurement was performed with 4 hydrogen-free deuterated benzene C6D6 liquid scintillation detectors, in the ES#2 experiment station on the beam line, at a distance of about 76 m from the neutron-production assembly. The total energy detection principle in combination with the pulse height weighting technique (PHWT) was applied to analyze the measured data. Results of the 232Th (n,γ) reaction cross section in the unresolved resonance region from 4 keV to 100 keV were obtained, which shows a good agreement with the existing experimental data from EXFOR, as well as with the evaluated data from the ENDF/B-VIII.0 and CENDL-3.1. In addition, the excitation function of 232Th (n,γ)233Th reaction in the unresolved resonance region was theoretically calculated by using the code TALYS-1.95. By fitting the experimental cross section and theoretical data, the average parameters in the unresolved resonance region were extracted. The datasets are openly available at http://dx.doi.org/10.11922/sciencedb.j00113.00015. 相似文献
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有机电致发光器件是有机光电子领域的研究热点,在平板显示和固体照明领域有着广阔的应用前景.目前,由于器件效率和稳定性的问题,蓝色磷光器件是有机电致发光器件的瓶颈,而蓝色磷光主体材料的选择是影响蓝色磷光器件性能的关键因素.综述了小分子蓝色磷光主体材料的最新研究进展,重点介绍了各类小分子蓝色磷光主体材料的设计思想、器件性能.包括空穴传输性主体材料、含硅主体材料、电子传输性主体材料、双极主体材料和可湿法加工的蓝色磷光小分子主体材料的结构、特点及相应器件性能.最后对小分子蓝色磷光主体材料的发展方向进行了展望. 相似文献
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Massive MIMO systems offer a high spatial resolution that can drastically increase the spectral and/or energy efficiency by employing a large number of antennas at the base station(BS).In a distributed massive MIMO system,the capacity of fiber backhaul that links base station and remote radio heads is usually limited,which becomes a bottleneck for realizing the potential performance gain of both downlink and uplink.To solve this problem,we propose a joint antenna selection and user scheduling which is able to achieve a large portion of the potential gain provided by the massive MIMO array with only limited backhaul capacity.Three sub-optimal iterative algorithms with the objective of sumrate maximization are proposed for the joint optimization of antenna selection and user scheduling,either based on greedy fashion or Frobenius-norm criteria.Convergence and complexity analysis are presented for the algorithms.The provided Monte Carlo simulations show that,one of our algorithms achieves a good tradeoff between complexity and performance and thus is especially fit for massive MIMO systems. 相似文献
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以香蒲为原料制备生物炭(Biochar), 并用不同试剂进行活化. 活化前的Biochar比表面积和孔体积很小, 分别为1.71 m2/g和0.00421 cm3/g, 而活化后的Biochar比表面积和孔容均增大, 其中经碳酸钠(Na2CO3)活化后的Biochar比表面积和孔容最大. 研究了Na2CO3与Biochar的质量比对其活化的影响, 确定了Na2CO3/Biochar最佳质量比为3∶1条件下, 得到的样品Biochar-Na2CO3-3具有最优的表面积和孔容, 分别为624 m2/g和0.211 cm3/g, 并具有优异的挥发性有机化合物(VOCs)吸附性能, 其正己烷、 甲苯和92号汽油的静态吸附容量分别为1.03, 0.814和0.751 g/g, 正己烷和甲苯的动态吸附容量分别为1.00和0.796 g/g, 且吸附稳定性相对较高, 优于商业用活性炭(AC)和硅胶(SG). 相似文献