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991.
992.
本文详细分析了中国长途智能网全网帐务计费结算流程设计,并就此方面指明了全面开通长途智能网业务并确保全网顺畅运转的关键所在。 相似文献
993.
Analysis of Optical Losses in a Photoelectrochemical Cell: A Tool for Precise Absorptance Estimation 下载免费PDF全文
Peter Cendula Ludmilla Steier Paolo A. Losio Michael Grätzel Jürgen O. Schumacher 《Advanced functional materials》2018,28(1)
Optical losses in a photoelectrochemical (PEC) cell account for a substantial part of solar‐to‐hydrogen conversion losses, but limited attention is paid to the detailed investigation of optical losses in PEC cells. In this work, an optical model of combined coherent and incoherent light propagation in all layers of the PEC cell based on spectroscopic measurements is presented. Specifically, photoelectrodes using transparent conductive substrates such as F:SnO2 coated with thin absorber films are focused. The optical model is verified for hematite photoanodes fabricated by atomic layer deposition and successfully used to determine wavelength‐dependent reflection, transmission, layer absorptances, and charge generation rates. Furthermore, the calculated absorptances enable 20–30% more accurate calculations of the absorbed photon‐to‐current efficiency of PEC cells. Our optical model is a powerful tool for the optimization of the optical performance of PEC cells focusing on single absorber or tandem configurations and represents a cornerstone of a complete (optical and electrical) model for PEC water splitting cells. 相似文献
994.
高校开水房是高校用水系统的重要组成部分,如果高校开水房的水龙头设计不合理,就会导致高校水资源严重浪费。因此,在高校开水房中使用节能型水龙头对于提高水资源的利用效率,减少水资源浪费具有十分重要的意义。本文主要研究了双调节节能型水龙头的设计目的、工作原理以及具体设计方案。 相似文献
995.
LDPC码在浅海水声通信中的应用研究 总被引:1,自引:0,他引:1
LDPC码具有编码增益高、译码速度快、可并行译码等特点,是当前编码界的一个研究热点。针对复杂多变、强多途和大起伏干扰的浅海水声信道,建立了LDPC码在浅海水声信道中仿真的模型,仿真研究了浅海水声信道下采用和一积译码算法的LDPC码性能。仿真结果表明,LDPC码在3径多途信道下性能优越;当译码迭代3—5次,码长1000bit左右时基本上能满足水声通信对误码率为10^-4的基本要求。 相似文献
996.
997.
Efficient and Stable Bifunctional Electrocatalysts Ni/NixMy (M = P,S) for Overall Water Splitting 下载免费PDF全文
Gao‐Feng Chen Tian Yi Ma Zhao‐Qing Liu Nan Li Yu‐Zhi Su Kenneth Davey Shi‐Zhang Qiao 《Advanced functional materials》2016,26(19):3314-3323
Development of easy‐to‐make, highly active, and stable bifunctional electrocatalysts for water splitting is important for future renewable energy systems. Three‐dimension (3D) porous Ni/Ni8P3 and Ni/Ni9S8 electrodes are prepared by sequential treatment of commercial Ni‐foam with acid activation, followed by phosphorization or sulfurization. The resultant materials can act as self‐supported bifunctional electrocatalytic electrodes for direct water splitting with excellent activity toward oxygen evolution reaction and hydrogen evolution reaction in alkaline media. Stable performance can be maintained for at least 24 h, illustrating their versatile and practical nature for clean energy generation. Furthermore, an advanced water electrolyzer through exploiting Ni/Ni8P3 as both anode and cathode is fabricated, which requires a cell voltage of 1.61 V to deliver a 10 mA cm?2 water splitting current density in 1.0 m KOH solution. This performance is significantly better than that of the noble metal benchmark—integrated Ni/IrO2 and Ni/Pt–C electrodes. Therefore, these bifunctional electrodes have significant potential for realistic large‐scale production of hydrogen as a replacement clean fuel to polluting and limited fossil‐fuels. 相似文献
998.
Precisely Controlled Hydration Water for Performance Improvement of Organic–Inorganic Perovskite Solar Cells 下载免费PDF全文
Li Ling Sijian Yuan Pengfei Wang Huotian Zhang Li Tu Jiao Wang Yiqiang Zhan Lirong Zheng 《Advanced functional materials》2016,26(28):5028-5034
Recently, intensive studies on the role of water molecule in the formation of organic–inorganic perovskite film have been reported. However, not only the contradictive phenomena but also the complex processing technique has hindered the widespread use of water molecule in perovskite preparation. Here the hydration water is introduced into the precursors instead of water. By precisely controlling the content of hydration water, a smoother and more uniform perovskite film is obtained through a simple one‐step spin coating method. The improvement of perovskite film quality leads to highly efficient planar perovskite solar cells. Summing up the device studies and the investigation of morphology, crystallization, and optical properties, the impact of water molecule in the formation of perovskite crystal and consequences of device performance is understood. Due to its universal adaptability and simplified process, precise control of hydration water is therefore of great utility to high quality perovskite films fabrication and large‐scale production of this upcoming photovoltaic technology. 相似文献
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1000.