186 resultados para 369.4, 019.9


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novel compound (BCBP) based on the modification of a well-known host material 4,4'-(bis(9-carbazolyl))biphenyl (CBP) through arylmethylene bridge linkage was synthesized, and fully characterized. Its thermal, electrochemical, electronic absorption and photoluminescent properties were studied. A high glass transition temperature (T-g) of 173 degrees C is observed for BCBP due to the introduction of the bridged structure, remarkably contrasting with a low T-g of 62 degrees C for CBP. Furthermore, the bridged structure enhances the conjugation and raises the HOMO energy, thus facilitating hole-injection and leading to a low turn-on voltage in an electroluminescent device. With the device structure of ITO/MoO3/NPB/Ir complex: BCBP/BCP/Alq(3)/LiF/Al, maximum power efficiencies of 41.3 lm/W and 6.3 lm/W for green- and blue-emitting OLED were achieved, respectively.

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A pre-column derivatization method for the sensitive determination of amines using the labeling reagent 1,2-benzo-3,4-dihydrocarbazole-9-isopropyl chloroformate (BCIC-Cl) followed by high-performance liquid chromatography with fluorescence detection has been developed. Identification of derivatives is carried out by high performance liquid chromatography/atmospheric pressure chemical ionization (LC-APCl-MS-MS). The chromophore of 2-(9-carbazole)-ethyl chloroformate (CEOC) reagent is replaced by 1,2-benzo-3,4-dihydrocarbazole-9-isopropyl functional group, which results in a sensitive fluorescence derivatizing reagent BCIC-Cl. BCIC-Cl can easily and quickly label amines. Derivatives are stable enough to be efficiently analyzed by high-performance liquid chromatography and show an intense protonated molecular ion corresponding m/z [MH](+) under APCl in positive-ion mode. The collision-induced dissociation of protonated molecular ion formed a product at m/z 260 corresponding to the cleavage of CH2-OCO bond. Studies on derivatization demonstrate excellent derivative yields over the pH 9.0-10.0. Maximal yields close to 100% are observed with a 3 to 4-fold molar reagent excess. In addition, the detection responses for BCIC derivatives are compared with those obtained using CEOC and FMOC as derivatization reagents. The ratios of l(BCIC)/l(CEOC) and l(BCIC)/l(FMOC) are, respectively, 1.23-3.14 and 1.25-3.08 for fluorescent (FL) responses (here, l is relative fluorescence intensity). Separation of the derivatized amines had been optimized on reversed-phase Eclipse XDB-C-8 column. Detection limits are calculated from 1.0 pmol injection, at a signal-to-noise ratio of 3, are 10.6-37.8 fmol. The mean interday accuracy ranges from 94 to 105% for fluorescence detection with the largest mean %CV < 7.5. The mean interday precision for all standards is < 6.0% of the expected concentration. Excellent linear responses are observed with coefficients of > 0.9997.

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A pre-column derivatization method for the sensitive determination of amino acids and peptides using the tagging reagent 1,2-benzo-3,4dihydrocarbazole-9-ethyl chloroformate (BCEOC) followed by high-performance liquid chromatography with fluorescence detection has been developed. Identification of derivatives was carried out by liquid chromatography/electrospray ionization mass spectrometry (LC/ESI-MS/MS). The chromophore of 2-(9-carbazole)-ethyl chloroformate (CEOC) reagent was replaced by 1,2-benzo-3,4-dihydrocarbazole functional group, which resulted in a sensitive fluorescence derivatizing reagent BCEOC. BCEOC can easily and quickly label peptides and amino acids. Derivatives are stable enough to be efficiently analyzed by high-performance liquid chromatography. The derivatives showed an intense protonated molecular ion corresponding m/z (M + H)(+) under electrospray ionization (ESI) positive-ion mode with an exception being Tyr detected at negative mode. The collision-induced dissociation of protonated molecular ion formed a product at m/z 246.2 corresponding to the cleavage of C-O bond of BCEOC molecule. Studies on derivatization demonstrate excellent derivative yields over the pH 9.0-10.0. Maximal yields close to 100% are observed with a 3-4-fold molar reagent excess. Derivatives exhibit strong fluorescence and extracted detzvatization solution with n-hexane/ethyl acetate (10:1, v/v) allows for the direct injection with no significant interference from the major fluorescent reagent degradation by-products, such as 1,2-benzo-3,4-dihydrocarbazole-9-ethanol (BDC-OH) (a major by-product), mono- 1,2-benzo-3,4-dihydrocarbazole-9-ethyl carbonate (BCEOC-OH) and bis-(1,2-benzo-3,4-dihydrocarbazole-9-ethyl) carbonate (BCEOC)(2). In addition, the detection responses for BCEOC derivatives are compared to those obtained with previously synthesized 2-(9-carbazole)-ethyl chloroformate (CEOC) in our laboratory. The ratios AC(BCEOC)/AC(CEOC) = 2.05-6.51 for fluorescence responses are observed (here, AC is relative fluorescence response). Separation of the derivatized peptides and amino acids had been optimized on Hypersil BDS C-18 column. Detection limits were calculated from 1.0 pmol injection at a signal-to-noise ratio of 3, and were 6.3 (Lys)-177.6 (His) fmol. The mean interday accuracy ranged from 92 to 106% for fluorescence detection with mean %CV < 7.5. The mean interday precision for all standards was < 10% of the expected concentration. Excellent linear responses were observed with coefficients of > 0.9999. Good compositional data could be obtained from the analysis of derivatized protein hydrolysates containing as little as 50.5 ng of sample. Therefore, the facile BCEOC derivatization coupled with mass spectrometry allowed the development of a highly sensitive and specific method for the quantitative analysis of trace levels of amino acids and peptides from biological and natural environmental samples. (c) 2005 Elsevier B.V. All rights reserved.

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研究了两种新型芴类衍生物9,9-二(2-乙基已基)-2,7-二咔唑-9H-芴(简记为DCZF)和9,9-二(2-乙基已基)-2,7-二(2-(4-甲氧基)苯-2,1-乙烯基)芴(简记为BMOSF)在N,N-二甲基甲酰胺(DMF)中的线性吸收和单光子荧光行为,并用脉冲宽度为38ps,重复频率为10Hz的1064 nm Nd:YAG脉冲激光研究了两种化合物的三光子吸收性质.结果表明:两种新材料的最大线性吸收峰分别位于330和380nm,吸收区域覆盖了270-420nm波段.两种化合物的荧光带位于蓝-紫区,中心

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4-Bromo-9,9'-spirobifluorene is facilely synthesized, and from this precursor, two ortho-linked oligo-9,9'-spirobifluorenes, 44BSF and 24TSF, are constructed. Devices with 24TSF as the full-hydrocarbon host material and Ir(ppy)(3) or (ppq)(2)Ir(acac) as the triplet emitter show maximum external quantum efficiencies of 12.6 and 10.5% for green and red electrophosphorescence, respectively.

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本文合成了两种新型取代酞菁铜(Ⅱ)配合物:四-4-(戊氧基-羰基)酞菁铜(Ⅱ)(A)和四-4-(癸氧基-羰基)酞菁铜(Ⅱ)(B),并通过元素分析、ESR、~1H-NMR和FT-IR进行了表征.用可见光谱研究了它们在氯仿溶液中的聚集形式;用X-ray粉末衍射方法研究了配合物的固相堆积排列结构.两种配合物的氯仿溶液在亚相(水)上的π-A曲线表明,它们均有明显的“气”“液”“固”变化过程;并能在不同的表面压力区间形成较好的单分子层和多分子层膜.

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观测了三-(2,4-二特戊基苯氧基)-(对羧基苯氧基)酞菁铜的共振与非共振拉曼光谱,比较二者的差异对某些振动谱带的归属进行了修正。

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在体积为0.025m~3的柱形容器中,采用底端中心点火方式,对4.1%的丙烷-空气、9.5%甲烷-空气预混气的顶端开口泄爆过程进行了实验研究。实验结果给出了不同泄爆面积和不同泄爆压力条件下容器的内压力发展历史。就不同泄爆条件对容器内爆炸发展产生的影响进行了讨论。

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本文是国内外关于波浪在淤泥海床上的衰减研究的综述.介绍了各种模型,包括:粘性流体模型、粘弹性流体模型、多孔弹性体模型、非线性的宾汉流体模型及边带阻尼理论.与实验及野外观察结果进行了比较.评论了各种模型的现状、优缺点及发展趋势.

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强激光辐照材料引起破坏的机理一直是从事激光军工应用研究者所关注的重大课题。本文就有关破坏机理理论方面的一些考虑和数学处理进行了分析讨论。

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中国科学院九五重大项目!(KZ951-A1-405)

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我国目前一年总耗煤量约12Tt,其中火电燃煤量占总耗煤量的较大份额。提高机组效率,减少二氧化碳等的排放历来被人们所重视,本文介绍了某410t/h锅炉的优化燃烧试验,可以对锅炉的优化燃烧试验有一定的指导意义。

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    本书系统地介绍了微/纳米力学测试技术中最常用的压入和划入技术及其典型应用。全书共分13章。测试技术方面,内容涉及接触力学、测试原理、方法、校准、仪器、力学参量、影响因素。典型应用方面,内容涉及在表面工程、微机电系统、生物、高聚物和金属玻璃等领域内的微/纳米力学行为的测试。本书可供力学、材料、物理、电子、机械、生物和化学等领域的研究人员、工程技术人员以及大专院校相关专业的师生参考。

目录

前言

第1章 绪论

1.1硬度的定义和分类

1.2纳米压入和划入技术的发展

1.3纳米压入和划入技术的特点

参考文献

第2章 压入接触力学

2.1弹性接触

2.1.1 Soeddon解

2.1.2锥形压针

2.1.3球形压针

2.1.4圆柱压针

2.2弹塑性接触

2.2.1塑性发生

2.2.2完全塑性

2.2.3材料响应

参考文献

第3章 纳米压入测试原理

3.1压入硬度和模量

3.2连续刚度测量

3.3载荷一深度数据确定的材料参数

3.3.1马氏硬度

3.3.2压入蠕变

3.3.3压入松弛

3.3.4压入弹性功和塑性功

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第4章 纳米压入测试方法

4.1压针类型

4.1.1玻氏压针

4.1.2立方角压针

4.1.3维氏压针

4.1.4努氏压针

4.1.5圆锥压针

4.1.6球形压针

4.1.7圆柱压针

4.1.8楔形压针

4.1.9考虑因素

4.2测试环节

4.2.1样品准备

4.2.2环境控制

4.2.3间距选择

4.2.4表面探测

4.2.5驱动方式

4.2.6测试步骤

4.2.7测试报告

参考文献

第5章 纳米压入的确认和校准

5.1直接确认和校准

5.2间接校准

5.3测试和校准的实例

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第6章 纳米压入和划入的测量仪器

6.1仪器技术指标的定义

6.2美国Mrs公司

6.3美国Hysitmn公司

6.4瑞士CSM公司

6.5英国MML公司

6.6澳大利亚CSIRO公司

6.7测量仪器的发展趋势

参考文献

第7章 力学参量的测量

7.1压入方式

7.1.1硬度和模量

7.1.2断裂韧度

7.1.3蠕变和粘弹行为

7.1.4压入应力??应变曲线

7.1.5加卸载曲线涉及的

部分现象

7.2划人方式

7.2.1块体材料

7.2.2薄膜材料

7.2.3粗糙度

7.3弯曲方式

7.3.1微悬臂梁静载弯曲

7.3.2微桥静载弯曲

7.3.3微结构疲劳

7.4吸引方式

7.5声发射测试

7.6温度测试

参考文献.

第8章 影响纳米压入测试的因素

8.1测试仪器的影响

8.1.1压针缺陷

8.1.2测试方法

8.1.3接触零点的确定

8.1.4载荷和位移的分辨力

8.2样品的表面状态和性质

8.2.1表面吸湿

8.2.2表面粗糙度

8.2.3残余应力

8.2.4凹陷和凸起变形

8.3纳米压入和划入测试所面临的问题

参考文献

第9章 在表面工程中的应用

9.1金属材料表面激光强化的力学表征

9.2硬质膜的力学和摩擦学性能评估

9.2.1显微硬度测试

9.2.2纳米压人测试

9.2.3纳米划入测试

9.2.4膜材的影响

参考文献

第10章 在微机电系统中的应用

10.1薄膜测试

10.1.1典型薄膜材料的硬度和模量

10.1.2薄膜疲劳

10.1.3淀积工艺对二氧化硅薄膜力学性质的影响

10.2微结构弯曲

10.2.1微结构的静态弯曲

10.2.2微结构的动态弯曲

参考文献

第11章 在生物及其相关材料中的应用

11.1人工林杉木管胞细胞壁

11.2人体腰椎骨

11.3存储液对人体牙齿微力学性能的影响

参考文献

第12章 在高聚物中的应用

12.1PMMA单轴拉伸和弯曲力学行为

12.2划入测试的理论分析

12.3韧性行为的描述

12.4脆性行为的描述

12.4.1温度效应

12.4.2应变率效应

参考文献

第13章 在金属玻璃中的应用

13.1硬度和屈服应力的关系

13.2不连续的塑性变形

13.3压痕形貌和微结构变化

13.4应变率效应

13.5钕基金属玻璃的变形行为

参考文献

附录 常见问题的回答

1测试数量

2压入间距

3压入深度

4泊松比的选择

5典型材料的参数

6断裂韧度测试压针的选择

7纳米薄膜的测试

8典型材料的压入变形行为

9显微硬度和纳米压入硬度的关系

10压入影响区及其边界效应

10.1压入影响区的有限元模拟

10.2边界距离影响的有限元模拟

10.3压人间距影响的测试

参考文献