970 resultados para Bicyclo[3.2.1]octane neolignans


Relevância:

100.00% 100.00%

Publicador:

Resumo:

The title compound, C13H11ClF3NO2, adopts a Z conformation. Halogen center dot center dot center dot oxygen interactions [Cl center dot center dot center dot O = 2.967 (3) angstrom] in the crystal packing lead to the formation of a dimer joined by two Cl center dot center dot center dot O bonds.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The amplified spontaneous emission properties of a 2, 1, 3-benzothiadiazole attached polyfluorene semiconductor polymer were studied. The conjugated polymer shows a high photoluminescence quantum efficiency of 67% and emits a narrowed blue emissive spectrum with a full width at half-maximum of 3.6 nm when optically pumped, indicating better lasing action. A threshold energy as low as 0.22 mJ pulse(-1) cm(-2), a net gain of 40.54 cm(-1) and a loss of 7.8 cm(-1) were obtained, demonstrating that this conjugated polymer could be a promising candidate as the gain medium for the fabrication of blue polymer lasers.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Four single polymers with two kinds of attachment of orange chromophore to blue polymer host for white electroluminescence (EL) were designed. The effect of the side-chain attachment and main-chain attachment on the EL efficiencies of the resulting polymers was compared. The side-chain-type single polymers are found to exhibit more efficient white EL than that of the main-chain-type single polymers. Based on the side-chain-type white single polymer with 4-(4-alkyloxy-phenyl)-7-(4-diphenylamino-phenyl)-2,1,3-benzothiadiazoles as the orange-dopant unit and polyfluorene as the blue polymer host, white EL with simultaneous orange (lambda(max) = 545 nm) and blue emission (lambda(max) = 432 nm/460 nm) is realised. A single-layer device (indium tin oxide/poly(3,4-ethylenedioxythiophene)/polymer/Ca/Al) made of these polymers emits white light with the Commission Internationale de l'Eclairage coordinates of (0.30,0.40), possesses a turn-on voltage of 3.5 V, luminous efficiency of 10.66 cd A(-1), power efficiency of 6.68 lm W-1, and a maximum brightness of 21240 cd m(-2).

Relevância:

100.00% 100.00%

Publicador:

Resumo:

By incorporating 4,7-diphenyl- 2,1,3 benzothiadiazole instead of 2,1,3-benzothiadiazole into the backbone of polyfluorene, we developed a novel series of green light- emitting polymers with much improved color purity. Compared with the state-of-the-art green light-emitting polymer, poly(fluorene-co-benzothiadiazole) (lambda max = 537 nm), the resulting polymers (lambda(max) = 521 nm) showed 10-20 nm blueshifted electroluminescence (EL) spectra and greatly improved color purity because the insertion of two phenylene units between the 2,1,3-benzothiadiazole unit and the fluorene unit reduced the effective conjugation length in the vicinity of the 2,1,3-benzothiadiazole unit. As a result, the resulting polymers emitted pure green light with CIE coordinates of (0.29, 0.63), which are very close to (0.26, 0.65) of standard green emission demanded by the National Television System Committee (NTSC). Moreover, the insertion of the phenylene unit did not affect the photoluminescence (PL) and EL efficiencies of the resulting polymers. PL quantum efficiency in solid films up to 0.82 was demonstrated. Single-layer devices (ITO/PEDOT/ polymer/Ca/Al) of these polymers exhibited a turn-on voltage of 4.2 V, luminous efficiency of 5.96 cd A(-1) and power efficiency of 2.21 lm W-1. High EL efficiencies and good color purities made these polymers very promising for display applications.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

利用差示扫描量热仪、X射线衍射仪、正交偏光显微镜研究了成核剂 1,3 :2 ,4-二 (亚苄基 ) -D山梨醇(DBS)对聚对苯二甲酸乙二醇酯 (PET) /聚 2 ,6-萘二甲酸乙二醇酯 (PEN)共混体系的结构及结晶形态的影响。结果表明 :成核剂的加入 ,使PET/PEN共混体系熔融起始温度升高 10℃左右 ,结晶峰形变尖锐 ,说明加入成核剂后有效促进了PET/PEN共混体系的结晶。实验结果表明 :成核剂含量低于 1%时 ,PET/PEN共混体系晶体的球晶完整。成核剂含量大于 3 %时 ,PET/PEN /DBS共混体系晶体的球晶碎小。成核剂的加入 ,能够有效地减小球晶尺寸和降低球晶的完善性

Relevância:

100.00% 100.00%

Publicador:

Resumo:

New single-polymer electroluminescent systems containing two individual emission species - polyfluorenes as a blue host and 2,1,3-benzothiadiazole derivative units as an orange dopant on the main chain - have been designed and synthesized. The resulting single polymers are found to have highly efficient white electroluminescence with simultaneous blue(lambda(max) = 421 nm/445 nm) and orange emission (lambda(max) = 564 nm)from the corresponding emitting species. The influence of the photoluminescence (PL) efficiencies of both the blue and orange species on the electroluminescence (EL) efficiencies of white polymer light-emitting diodes (PLEDs) based on the single-polymer systems has been investigated. The introduction of the highly efficient 4,7-bis(4-(N-phenyl-N-(4-methylphenyl)amino)phenyl)-2,1,3-benzothiadiazole unit to the main chain of polyfluorene provides significant improvement in EL efficiency. For a single-layer device fabricated in air (indium tin oxide/poly(3,4-ethylenedioxythiophene): poly(styrene sulfonic acid/polymer/Ca/Al), pure-white electroluminescence with Commission Internationale de l'Eclairage (CIE) coordinates of (0.35,0.32), maximum brightness of 12 300 cd m(-2), luminance efficiency of 7.30 cd A(-1), and power efficiency of 3.34 lm W-1 can be obtained.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Monolayer protected gold nanoparticles (MPCs) are the focus of recent research for their stability and are deemed as the building blocks of bottom-up strategies. In this Letter, 3-mercapto-1,2-propanediol monolayer protected gold nanoparticles (MPD-MPCs) were synthesized and characterized by transmission electron microscopy, UV/Vis spectroscopy, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The value of quantized double-layer capacitance (1.13 aF) of MPD-MPCs in aqueous media was obtained by differential pulse voltammograms.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Nine triphenyltin - 2 - (1,2 - ethylenedithio) methylene - 3 - oxo - 5 - aryl - 4 - pentenicates were synthesized. The crystal structure of the title compound 3b (C33H28O3S2Sn) was determined by X - ray diffraction analysis. The crystal belongs to triclinic system, space group P(1)overbar with a = 0.9074 (2) nm, b = 1.6809(3)nm, c = 2.1834(4)nm, alpha =77.57(3)degrees, beta = 88.04(3)degrees, gamma = 89.47(3)degrees, V = 3.2503nm(3), Z = 2, R = 0.0592. In crystal of 3b, there exist intramolecular 0-Sn coordination bonds, with carboxylate group acting as a bidentate ligand: Sn(1)-0(1) = 0.2086(5) and Sn(1)-0(2) = 0.2594nm, having a deformed trigonal bipyramidal geometry.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

由2-(1,2-亚乙二硫)亚甲基-3-羰基-5-芳基-4-戊烯酸与三苯基氢氧化锡反应,合成了九个标题化合物3.用X射线衍射法测定了3b的晶体结构.该晶体属三斜晶系,空间群Pl,α=0.9074(2)nm,b=1.6809(3)nm,c=2.1834(4)nm,α=77.57(3)°,β=88.04(3)°,γ=89.47(3)°,V=3.2503nm~3,Z=2;R=0.0592.由锡氧原子间距离可推测,该晶体中羧酸根作为双齿配体与锡原子形成了分子内五配位结构.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Three title compounds were prepared and the structure of title compound 2 was characterized by IR, H-1 NMR, C-13 NMR, Sn-119 NMR spectroscopy and the crystal structure of compound 2a was determined by X-ray analysis with the final R indices[I >2 sigma (I)] R-1 = 0.0350 and R-2,R-omega = 0.0888. The crystal of compound 2a belongs to triclinic system, space group P1 with a = 1.0598(6) nm, b = 1.307 4(10) nm, c = 1.378 6(10) nm, alpha = 62.666(7)degrees, beta = 72.530(2)degrees, gamma = 80. 680(2)degrees, V = 1.618 0 nm(3), D-x = 1. 444 g (.) cm(-3), Z = 1, F (000) = 728. The bond length of Sn1-O1 is 0. 2076 nm and Sn1 . . . O2 distance is 0.301 3 nm. The coordination about the tin atom can be considered as a distorted tetrahedral. The detail values of H-1 NMR, C-13 NMR, Sn-119 NMR, (2)J(119Sn-1H) and J(119Sn-13C) were obtained. delta (119Sn) = 23.836, (2)J(119Sn-1H) = 88.0 Hz, (1)J(119Sn-13C) = 347.1 Hz, (2)J(119Sn-13C) = 45.6 Hz.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

用一维 1HNMR、13CNMR方法研究了2,2′-(3,4 -四酸二酐)二苯甲酰氧基 -1,1′联萘的结构 ,并通过二维1H - 1H同核相关、13C - 1H异核相关及13C - 1H异核远程相关谱进一步地确定其1H谱和13C谱中各谱峰的归属 ,为同类化合物的表征提供了依据。

Relevância:

100.00% 100.00%

Publicador:

Resumo:

本文报道9种新的含磷杂环化合物的电子轰击质谱(EIMS),并应用B/E、B2/E联动扫描及精确质量测量技术,探讨了该类化合物的质谱断裂机理,发现骨架重排及开环反应是该类化合物主要的质谱特征,而R2基因对重排过程有很大影响。

Relevância:

100.00% 100.00%

Publicador:

Resumo:

本文研究了TritonX-100在浊点条件下对钴-4-(5-氯-2-吡啶偶氮)-1,3-二氨基苯(5-Cl-PADAB)络合物的析相条件,在pH4.0~6.0介质中,将胶束溶液加热到92±1℃,保持40min,络合物即被TritonX-100相富集。富集液在575nm测定吸光度,钴含量在0~4μg/5ml范围内服从比尔定律,干扰离子可在TritonX-100析相液中加入H_2SO_4消除。拟定的方法灵敏、简捷,已用于不经分离直接测定人发及自来水中痕量钴。

Relevância:

100.00% 100.00%

Publicador:

Resumo:

应用EI质谱和联动扫描技术研究了13个有机磷杂环化合物,讨论了主要离子的形成过程,分子离子在EI条件下的各种重排反应和取代基对不同解离反应产物离子相对强度的影响。

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The mass spectral behaviour of 15 new type of organic phosphorus compounds with a considerable insecticidal activity, 1, 3,2-oxazaphospholidine 2-sulfides derivatives, under 70 eV electron impact has been studied by means of high and low resolution mass spectrometry as well as by B/E linked scan and MIKES/CID analysis. Discussion is focused into the isomerization between oxygen and sulphur in molecules and some rearrangement reactions.