功率控制误差对CDMA蜂窝系统性能的影响

通过将接收信号功率描术这为地数正态分布的随机变量，其标准方差表示功率控制的误差，分析了在ＣＤＤＭＡ蜂窝系统中，功率控制误差、软切换方案及话音激活技术对ＣＤＭＡ蜂窝系统性能的影响。计算表明，采用精确的功率控制技术。合理的软切换方案和话音激活技术可以显著地改善系统的性能。     

Multicolor Tunable Emission from Organogels Containing Tetraphenylethene,Perylenediimide, and Spiropyran Derivatives

A dendron‐substituted tetraphenylethene low molecular weight gelator (LMWG)compound, LMWG 1, is designed and investigated. Gelation‐induced fluorescence enhancement is observed for the gel based on LMWG 1 and its fluorescence can be reversibly tuned by varying the temperature of the ensemble. The photoinduced energy‐transfer can occur between LMWG 1 and PI 2 (perylene diimide) in the gel phase, but it cannot occur in the corresponding solution. The emission color of the gel of LMWG 1 and PI 2 can be tuned from cyan, yellow, to red by varying the concentration of PI 2 . By taking advantage of the photochromic transformation of spiropyran, the emission color of the organogels based on LMWG 1 and SP 3 can be switched by alternating UV and visible‐light irradiations. The emission color can also be tuned by varying the irradiation time. In this way, organogels based on LMWG 1 with multiemission color can be achieved in the presence of SP 3 after light irradiations.     

Preparation and Characterization of a New Complex of C60 with 7714AS-Dimethyltetrathiodiazafulvalene (DMTTDF)

Abstract

A new charge transfer complex based on C₆₀ was synthesized, and characterized elementarily by element analysis, FT-IR spectrum, Raman spectrum, and X-ray diffraction method. the magnetic properties of the complex were measured by ESR and a SQUID-magnetometer.     

低压电源自动投入装置要求解析(待续)

针对低压电源自动投入装置的控制要求、自投装置的复归方式和ATSE的应用,依据国家现行标准、规范的相关规定,提出笔者的一些看法,并以国家建筑标准图01D302-3《低压母线分段断路器二次接线图(续)》中施耐德M型断路器为例,解析其实现控制要求的措施.     

Synthesis and electrochemical properties of novel oligo-TTF donors

A series of novel oligomeric electron donors containing two to six TTF cores (5–11) were synthesized. The structures were assigned by NMR spectroscopy, infrared spectrometry and mass spectra. Their electrochemical properties were investigated by cyclic voltammetry (CV). All the compounds exhibited two pairs of nearly ideal redox waves. No distinct shift of the redox potentials was observed when TTF units increased.     

Inkjet‐Printed Organic Electrodes for Bottom‐Contact Organic Field‐Effect Transistors

A graphite thin film was investigated as the drain and source electrodes for bottom‐contact organic field‐effect transistors (BC OFETs). Highly conducting electrodes (10² S cm^?1) at room temperature were obtained from pyrolyzed poly(l,3,4‐oxadiazole) (PPOD) thin films that were prepatterned with a low‐cost inkjet printing method. Compared to the devices with traditional Au electrodes, the BC OFETs showed rather high performances when using these source/drain electrodes without any further modification. Being based on a graphite‐like material these electrodes possess excellent compatibility and proper energy matching with both p‐ and n‐type organic semiconductors, which results in an improved electrode/organic‐layer contact and homogeneous morphology of the organic semiconductors in the conducting channel, and finally a significant reduction of the contact resistance and enhancement of the charge‐carrier mobility of the devices is displayed. This work demonstrates that with the advantages of low‐cost, high‐performance, and printability, PPOD could serve as an excellent electrode material for BC OFETs.     

Self-assembly and optical properties of hydrogen bonded nanostructures containing C60 and pyrene

A new supramolecular system between a barbituric acid-substituted fullerene derivative (1) and dipyrenemethyl-substituted melamine (2) through hydrogen-bonding interaction was prepared. The formation of hydrogen bonding was confirmed by ¹H NMR studies in CDCl₃/CS₂. The photocurrent generation of the self-assembled film of 2 · 1 was measured and a cathodic photocurrent response was obtained. Scanning electron microscopy (SEM) images showed that the self-assembly system could fabricate two different types of aggregated structures: nanoparticles and nanorods.     

High‐Performance Organic Transistor Memory Elements with Steep Flanks of Hysteresis

High‐performance organic transistor memory elements with donor‐polymer blends as buffer layers are presented. These organic memory transistors have steep flanks of hysteresis with an ON/OFF memory ratio of up to 2 × 10⁴, and a retention time in excess of 24 h. Inexpensive materials such as poly(methyl methacrylate), ferrocene and copper phthalocyanine are used for the device fabrication, providing a convenient approach of producing organic memory transistors at low cost and high efficiency.