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41.
The image displaying methods used in a millimeter wave radiometric imaging system have great influence on its imaging quality. In order to obtain high quality millimeter wave radiometric images, intensive studies on the image displaying methods are needed. This paper describes the image displaying method of Ground-based 8mm Millimeter Wave Radiometric Imaging (GMWRI) system and compares two different image displaying methods. The experimental results prove the unequal size element arc displaying method fits GMWRI system better.  相似文献   
42.
In this contribution, we demonstrate a new effective methodology for constructing highly efficient and durable poly(p‐phenyleneethynylene) (PPE) containing emissive material with nonaggregating and hole‐facilitating properties through the introduction of hole‐transporting blocks into the PPE system as the grafting coils as well as building the energy donor–acceptor architecture between the grafting coils and the PPE backbone. Poly(2‐(carbazol‐9‐yl)ethyl methacrylate) (PCzEMA), herein, is chosen as the hole‐transporting blocks, and incorporated into the PPE system as the grafting coils via atom transfer radical polymerization. The chemical structure of the resultant copolymer, PPE‐g‐PCzEMA, was characterized by NMR and gel permeation chromatography, showing that the desirable copolymer was obtained with the narrow polydispersity. The increased thermal stability of PPE‐g‐PCzEMA was confirmed by thermogravimetric analysis and differential scanning calorimetry along with its macroinitiator. The optoelectronic properties of this copolymer were studied in detail by ultraviolet‐visible absorption, photoluminescence emission and excitation spectra, and cyclic voltammogram (CV). The results indicate that PPE‐g‐PCzEMA exhibits the solid‐state luminescent property dominated by individual lumophores, and also the energy transfer process from the PCzEMA blocks to the PPE backbone with a relatively higher energy transfer efficiency in the solid‐state compared to that of the solution state. Additionally, the hole‐injection property is greatly facilitated due to the presence of PCzEMA, as confirmed by CV profiles. All these data indicate that PPE‐g‐PCzEMA is a good candidate for use in optoelectronic devices. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3776–3787, 2007  相似文献   
43.
Five novel fluorene‐containing polymers, poly[(9,9‐dimethylfluoren‐2‐yl)acetylene] ( PFA1 ), poly[(1‐pentyl‐2‐(9,9‐dimethylfluoren‐2‐yl)acetylene) ( PFA2 ), poly[1‐decyl‐2‐(9,9‐dimethylfluoren‐2‐yl)acetylene] ( PFA3 ), poly[1‐phenyl‐2‐(9,9‐dimethylfluoren‐2‐yl)acetylene] ( PFA4 ), and poly[1‐(3,4‐difluorophenyl)‐2‐(9,9‐dimethylfluoren‐2‐yl)acetylene] ( PFA5 ) were synthesized by the polymerization of the corresponding fluorene‐substituted acetylenic monomers ( M1–M5), using WCl6, MoCl5, and TaCl5 as catalysts and n‐Bu4Sn as a cocatalyst. The synthesized polymers were thermally stable and readily soluble in common organic solvents. The degradation temperatures for a 5% weight loss of the polymers were ∼352–503 °C under nitrogen. PFA1–PFA5 show emission peaks from 402 to 590 nm. Besides, their electroluminescent properties were studied in heterostructure light‐emitting diodes (LEDs), using PFA2–PFA5 as an emitting layer. The PFA5 device revealed an orange‐red emission peak at 602 nm with a maximum luminescence of 923 cd/m2 at 8 V. A device with the ITO/PEDOT/ a mixture of PFA2 (98 wt %) and PFA5 (2 wt %)/Ca/Al showed near white emission. Its maximum luminance and current efficiency are 450 cd/m2 at 15 V and 1.3 cd/A, respectively. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 519–531, 2006  相似文献   
44.
Two series of poly(2,3‐diphenyl‐1,4‐phenylenevinylene) (DP‐PPV) derivatives containing multiple bulky substituents were synthesized. In the first series, two different groups were incorporated on C‐5,6 positions of the phenylene moiety to increase steric hindrance and to obtain blue‐shifted emissions. In the second series, bulky fluorenyl groups with two hexyl chains on the C‐9 position were introduced on two phenyl pendants to increase the solubility as well as steric hindrance to prevent close packing of the main chain. Polymers with high molecular weights and fine‐tuned electro‐optical properties were obtained by controlling the feed ratio of different monomers during polymerization. The maximum photoluminescent emissions of the thin films are located between 384 and 541 nm. Cyclic voltammetric analysis reveals that the band gaps of these light‐emitting materials are in the range from 2.4 to 3.3 eV. A double‐layer EL device with the configuration of ITO/PEDOT/P4/Ca/Al emitted pure green light with CIE′1931 at (0.24, 0.5). Using copolymer P6 as the emissive layer, the maximum luminescence and current efficiency were both improved when compared with the homopolymer P4. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6738–6749, 2006  相似文献   
45.
符号几何规划的一种分解方法   总被引:1,自引:0,他引:1  
针对符号几何规划提出了一种直接的分解方法,将难于求解的符号几何规划问题等价地转化为一个非线性程度很低的可分离规划,为寻求困难度高且规模较大的符号几何规划问题的求解提供了一种方法,特别是经此方法分解后的每个子问题均易于求解,最后给出了数值实例,验证了此方法的有效性.  相似文献   
46.
染料中间体间氨基-N-取代-苯磺酰胺的合成研究   总被引:2,自引:0,他引:2  
以间氨基苯磺酸为原料,经乙酰化保护氨基,用氯磺酸/氯化亚砜将磺箕转变为磺酰氯,再分别与氨基G酸、吐氏酸、γ-酸、6-氨基-1,3-萘二磺酸、5,6-二氨基-1,3-萘二磺酸胺化缩合,水解去乙酰基,较高收率地合成了间氨基-N-取代-苯磺酰胺类染料中间体。产物结构经元素分析、红外、核磁和质谱确证。  相似文献   
47.
微量元素与精神病的研究   总被引:2,自引:0,他引:2  
一些基础医学实验研究和临床观察的资料表明,精神疾病患者体内的微量元素存在着显著的异常,已引起了国内外学者广泛关注,本文根据近年来的国内外文献报道,概述了微量元素锌(Zn),铜(Cu),铁(Fe)和常量元素钙(Ca),镁(Mg)的生理作用及与精神病关系的研究进展。  相似文献   
48.
7-十二烯基-8-羟基喹啉的合成   总被引:1,自引:0,他引:1  
7-十二烯基-8-羟基喹啉是一种新型螯合型萃取剂(Kelex 100的主要成份)。它是(1a)和(1b)异构体的混合物。本文报道了利用1-氯-1,1,3,3-四甲基丁烷与过量丁二烯-[1,3]的1,4加成反应合成重要中间体1-氯-5,5,7,7-四甲基辛烯-[2](3)的方法,此法具有室温、常压、产率高、设备简单、操作方便等优点。  相似文献   
49.
超声波作用下5, 5-二取代乙内酰脲的合成   总被引:4,自引:0,他引:4  
李记太  王树  李立军 《有机化学》1995,15(5):558-560
本文以氰化钠水溶液、碳酸铵和相应的醛或酮为原料, 于25℃~45℃超声波作用3~4h合成八种5, 5-二取代乙内酰脲, 收率30.1~100%。与传统方法比较, 反应时间缩短, 产品收率提高。  相似文献   
50.
通过环十二酮与 N -取代氨基硫脲的缩合反应 ,合成了一系列 N -取代环十二酮缩氨基硫脲 ,经Mn O2 氧化关环 ,得到 1 5种未见文献报道的标题化合物 ,其结构经 IR,1 3C NMR,元素分析的确证 .初步实验表明 ,部分化合物具有一定的杀菌活性  相似文献   
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