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121.
TD-LTE网络优化的信令分析算法研究 总被引:1,自引:0,他引:1
TD-LTE网络建设目前还是处在发展的阶段,在TD-LTE网络优化方面还要经过一段时间的摸索,根据应用方向的不同,在一定程度上针对TD-LTE网络优化的信令分析算法也存在着差异,文章主要针对TD-LTE网络优化的信令分析算法进行较为系统的研究及探讨,展现出TD-LTE网络优化的信令分析算法的必要性,以及在实际应用中的效果,主要是为了完善网络优化的水平,借以提高TD-LTE网络优化的信令的可靠性,保证实际运用中不出现信令偏差,达到良好的使用效果,不断加大对TD-LTE网络优化的信令分析算法的实际效果监测,使其在网络优化领域能够得到肯定。 相似文献
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描述了—个基于低温共烧陶瓷(LTCC)封装技术的微波振荡器的设计和制作。电路集成了谐振器等无源器件在多层LTCC基板内部。并介绍了电路工作在5.6GHz时测试和计算的结果。此电路具有紧凑的结构和良好的相噪性能。 相似文献
125.
介绍了基下TMS320C62X的某雷达制导信号处理器的硬件系统,着重论述了在实际系统中信号处理器的硬件结构和实现;该设计充分利用了TMS320C6202芯片的软硬件资源,如DMA、中断、多通道串口、扩展总线等;样机的研制验证了该方案的可行性。 相似文献
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本文介绍堆取料机电气自控系统的结构设计、组态、控制原理,并结合SIEMENS自控产品PLCS7—300、变频器6SE70、触摸屏TP27、PROFIBUS网络通讯,对堆取料机自控系统做了重点论述。 相似文献
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Jianfeng Li Min Liu Kun Yang Yimei Wang Junwei Wang Zhicai Chen Kui Feng Dong Wang Jianqi Zhang Yongchun Li Han Guo Zhixiang Wei Xugang Guo 《Advanced functional materials》2023,33(23):2213911
Designing n-type polymers with high electrical conductivity remains a major challenge for organic thermoelectrics (OTEs). Herein, by devising a novel selenophene-based electron-deficient building block, the pronounced advantages of selenium substitution in simultaneously enabling advanced n-type polymers is demonstrated with high mobility (≈2 orders of magnitude higher versus their sulfur-based analogues due to both intensified intra- and inter-chain interactions) and much improved n-doping efficiency (enabled by the largely lowered LUMO level with a ≈0.2 eV margin) of the resulting polymers. Via side chain optimization and donor engineering, the selenium-substituted polymer, f-BSeI2TEG-FT, achieves a highest conductivity of 103.5 S cm−1 and power factor of 70.1 µW m−1 K−2, which are among the highest values reported in literature for n-type polymers, and f-BSeI2TEG-FT greatly outperformed the sulfur-based analogue polymer by 40% conductivity increase. These results demonstrate that selenium substitution is a very effective strategy for improving n-type performance and provide important structure-property correlations for developing high-performing n-type OTE materials. 相似文献
129.
Zhifeng Jiang Zhiquan Zhang Jianli Liang Min Zhou Daobin Liu Danjun Mao Qun Zhang Wei Zhang Huaming Li Li Song Taicheng An Po Keung Wong Chun-Sing Lee 《Advanced functional materials》2023,33(29):2301785
Solar-driven CO2 reduction reaction (CO2RR) with water into carbon-neutral fuels is of great significance but remains challenging due to thermodynamic stability and kinetic inertness of CO2. Biomass-derived nitrogen-doped carbon (N-Cb) have been considered as promising earth-abundant photocatalysts for CO2RR, although their activities are not ideal and the reaction mechanism is still unclear. Herein, an efficient catalyst is developed for CO2-to-CO conversion realized on diverse N-Cb materials with hierarchical pore structures. It is demonstrated that the CO2-to-CO conversion preferentially takes place on positively charged carbon atoms next to pyridinic-N using two representatives treated pollens with the largest difference in pyridinic-N density and N content as model photocatalysts. Systematic experimental results indicate that surface local electric field originating from charge separation can be boosted by hierarchical pore structures, doped N, as well as pyridinic-N. Mechanistic studies reveal that positively charged carbon atoms next to pyridinic-N serve as active sites for CO2RR, reduce the energy barrier on the formation of CO*, and facilitate the CO2RR performance. All these benefits cooperatively contribute to treated chrysanthemum pollen catalyst exhibiting excellent CO formation rate of 203.2 µmol h−1 g−1 with 97.2% selectivity in pure water vapor. These results provide a new perspective into CO2RR on N-Cb, which shall guide the design of nature-based photocatalysts for high-performance solar-fuel generation. 相似文献
130.
Dong Hyun Lee Younghwan Lee Yong Hyeon Cho Hyojun Choi Se Hyun Kim Min Hyuk Park 《Advanced functional materials》2023,33(42):2303956
Ferroelectric materials are considered ideal for emerging memory devices owing to their characteristic remanent polarization, which can be switched by applying a sufficient electric field. However, even several decades after the initial conceptualization of ferroelectric memory, its applications are limited to a niche market. The slow advancement of ferroelectric memories can be attributed to several extant issues, such as the absence of ferroelectric materials with complementary metal–oxide–semiconductor (CMOS) compatibility and scalability. Since the 2010s, ferroelectric memories have attracted increasing interest because of newly discovered ferroelectricity in well-established CMOS-compatible materials, which are previously known to be non-ferroelectric, such as fluorite-structured (Hf,Zr)O2 and wurtzite-structured (Al,Sc)N. With advancing material fabrication technologies, for example, accurate chemical doping and atomic-level thickness control, a metastable polar phase, and switchable polarization with a reasonable electric field can be induced in (Hf,Zr)O2 and (Al,Sc)N. Nonetheless, various issues still exist that urgently require solutions to facilitate the use of the ferroelectric (Hf,Zr)O2 and (Al,Sc)N in emerging memory devices. Thus, ferroelectric (Hf,Zr)O2 and (Al,Sc)N are comprehensively reviewed herein, including their fundamental science and practical applications. 相似文献