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991.
Wei Huang Wenjuan Zhang Shaofeng Liu Tongling Liang Wen‐Hua Sun 《Journal of polymer science. Part A, Polymer chemistry》2011,49(8):1887-1894
A series of trichlorotitanium complexes containing 2‐(1‐(arylimino)propyl)quinolin‐8‐olates was synthesized by stoichiometric reaction of titanium tetrachloride with the corresponding potassium 2‐(1‐(arylimino)propyl)quinolin‐8‐olates and was fully characterized by elemental analysis, nuclear magnetic resonance spectroscopy, and by single‐crystal X‐ray diffraction study of representative complexes. All titanium complexes, when activated with methylaluminoxane, exhibited high catalytic activity toward ethylene polymerization [up to 1.15 × 106 g mol?1(Ti) h?1] and ethylene/α‐olefin copolymerization [up to 1.54 × 106 g mol?1 (Ti) h?1]. The incorporation of comonomer was confirmed to amount up to 2.82 mol % of 1‐hexene or 1.94 mol % of 1‐octene, respectively. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
992.
993.
Mui Siang Soh Sonsoles Amor Garcia Santamaria Evan Laurence Williams Marta Pérez‐Morales Henk J. Bolink Alan Sellinger 《Journal of Polymer Science.Polymer Physics》2011,49(7):531-539
A new class of solution processable dendrimers based on cyclic phosphazene (CP) cores have been prepared and used as host materials for blue and green organic light emitting diodes (OLEDs). The dendrimers are prepared in high yield from minimal step reactions, are soluble in common solvents for solution processing, are amorphous, and have excellent thermal properties necessary for application in OLEDs. OLED efficiencies of 10.3 cd/A (4.2 lm/W) and 35.3 cd/A (33.5 lm/W) were achieved using commercially available FIrpic and Ir(mppy)3 as blue and green phosphorescent emitters, respectively. These efficiencies were 2× higher than control devices prepared using poly(N‐vinylcarbazole), the most commonly used host material in solution processed phosphorescent OLEDs. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011 相似文献
994.
Xiao‐Hua Ma Li‐Min Fu Yunfeng Zhao Xi‐Cheng Ai Jian‐Ping Zhang Yu Han Zhi‐Xin Guo 《Journal of Polymer Science.Polymer Physics》2011,49(9):649-656
Achiral nonlinear optical (NLO) chromophores 1,3‐diazaazulene derivatives, 2‐(4′‐aminophenyl)‐6‐nitro‐1,3‐diazaazulene (APNA) and 2‐(4′‐N,N‐diphenylaminophenyl)‐6‐nitro‐1,3‐diazaazulene (DPAPNA), were synthesized with high yield. Despite the moderate static first hyperpolarizabilities (β0) for both APNA [(136 ± 5) × 10?30 esu] and DPAPNA [(263 ± 20) × 10?30 esu], only APNA crystal shows a powder efficiency of second harmonic generation (SHG) of 23 times that of urea. It is shown that the APNA crystallization driven cooperatively by the strong H‐bonding network and the dipolar electrostatic interactions falls into the noncentrosymmetric P212121 space group, and that the helical supramolecular assembly is solely responsible for the efficient SHG response. To the contrary, the DPAPNA crystal with centrosymmetric P‐1 space group is packed with antiparalleling dimmers, and is therefore completely SHG‐inactive. 1,3‐Diazaazulene derivatives are suggested to be potent building blocks for SHG‐active chiral crystals, which are advantageous in high thermal stability, excellent near‐infrared transparency and high degree of designing flexibility. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011 相似文献
995.
Kang‐Jun Baeg Dongyoon Khim Dong‐Yu Kim Soon‐Won Jung Jae Bon Koo In‐Kyu You Henry Yan Antonio Facchetti Yong‐Young Noh 《Journal of Polymer Science.Polymer Physics》2011,49(1):62-67
Inkjet‐printed high speed polymeric complementary circuits are fabricated using an n‐type ([poly{[N,N′‐bis(2‐octyldodecyl)‐naphthalene‐1,4,5,8‐bis(dicarboximide)‐2,6‐diyl]‐alt‐5,5′‐(2,2′‐dithiophene)} [P(NDI2OD‐T2), Polyera ActivInk N2200] and two p‐type polymers [poly(3‐hexylthiophene) (P3HT) and a dithiophene‐based polymer (Polyera ActivInk P2100)]. The top‐gate/bottom‐contact (TG/BC) organic field‐effect transistors (OFETs) exhibit well‐balanced and very‐high hole and electron mobilities (μFET) of 0.2–0.5 cm2/Vs, which were enabled by optimization of the inkjet‐printed active features, small contact resistance both of electron and hole injections, and effective control over gate dielectrics and its orthogonal solvent effect (selection of poly(methyl methacrylate) and 2‐ethoxyethanol). Our first demonstrated inkjet‐printed polymeric complementary devices have been integrated to high‐performance complementary inverters (gain >30) and ring oscillators (oscillation frequency ~50 kHz). We believe that the operating frequency of printable organic circuits can be further improved more than 10 MHz by fine‐tuning of the device architecture and optimization of the p‐ and n‐channel semiconductor processing. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2010 相似文献
996.
Lin Ke Shuang Fang Lim Soo Jin Chua 《Journal of Polymer Science.Polymer Physics》2001,39(14):1697-1703
Dark spot growth rate tracing experiments performed on an organic light‐emitting device show that moisture entering into the device is relatively properly fitted by Fick's diffusion equation in the substrate/indium tin oxide (ITO)/hole transport layer (HTL)/silver (Ag) structure. It is believed that the moisture is dissolved into the polymer layer, which results in a decrease in the diffusion coefficient in the device with the substrate/ITO/HTL/electroluminescent (EL) polymer/Ag structure. The diffusion and chemical reaction occurring in the cathode layer further decreases the diffusion coefficient in the device with the substrate/ITO/HTL/EL polymer/calcium/Ag structure. Useful parameters, such as diffusion and solubility constants, describing possible mechanisms happening during dark spot growth on organic light‐emitting diode devices are extracted. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 1697–1703, 2001 相似文献
997.
深亚微米生产线中的超纯水装置 总被引:4,自引:0,他引:4
本文依据深亚微米技术的要求,结合实例,扼要介绍这种世界的超纯水装置。讨论了TOC/DO或WC/Si低于1PPb和用水点无微粒的技术以及费用等项热点问题。 相似文献
998.
Shaowei Zhang Dr. Junwei Zhao Pengtao Ma Prof. Dr. Jingyang Niu Prof. Jingping Wang 《化学:亚洲杂志》2012,7(5):966-974
Five rare-earth–transition-metal (RE–TM) heterometal organic–inorganic hybrids based on Keggin-type silicotungstates and mixed ligands H2pzda (pzda=pyrazine-2,3-dicarboxylate) and en (en=ethylenediamine) (enH2)[Cu(en)2(H2O)]2{[Cu(en)2][Cu(en)2(H2O)][(α-SiW11 O39)RE(H2O)(pzda)]}2⋅n H2O (n≈4; RE=YIII ( 1 ), DyIII ( 2 ), YbIII ( 3 ), and LuIII ( 4 )) and [Cu(en)2(H2O)]2{[Cu(en)2]2[Cu(pzda)2][(α-H2SiW11O39)Ce(H2O)]2}⋅n H2O ( 5 ; n≈8) have been hydrothermally synthesized and structurally characterized. Compounds 1–5 all contain the dimeric mono-RE substituted Keggin [RE(α-SiW11O39)]210− subunits linked by H2pzda ligands. Interestingly, 1–4 exhibit discrete structures, in which the H2pzda ligand acts as a tetradentate ligand to bind the RE and Cu cations, whereas 5 displays a 1D double-chain architecture, in which the H2pzda ligand adopts a new pentadentate mode to connect the Ce and Cu cations. To our knowledge, 1–5 represent the first monovacant Keggin-type silicotungstates containing both RE–TM heterometals and mixed ligands. The luminescence of 2 is derived from the combination of the DyIII cations and H2pzda ligands, whereas the luminescence properties of 1 and 3–5 are attributable to the H2pzda ligands. 相似文献
999.
1000.
We study the degradation mechanisms of ultraviolet (UV) organic photodetectors (OPDs). Contrary to expectations, we determine that the bulk of the organic layers in UV OPDs is stable under prolonged UV irradiation, showing no detectable changes in photophysical characteristics such as photoluminescence yield and exciton lifetime and thus not contributing to the observed degradation behavior of UV OPDs. However, the results show that the organic/electrode interfaces in UV OPDs, including indium tin oxide (ITO)/organic and organic/metal ones, are susceptible to UV irradiation, leading to a deterioration in both charge injection and extraction across the interfaces. The degradation of the organic/electrode interfaces in UV OPDs is essentially induced by UV-generated excitons in their vicinity and may be responsible for nearly 100% of the photo-current loss of UV OPDs. Approaches for improving the photo-stability of organic/electrode interfaces, and thus the lifetime of UV OPDs, are also investigated. We demonstrate that the use of thin (∼0.5 nm) interfacial layers such as lithium acetylacetonate at organic/metal interfaces can significantly reduce the interfacial degradation, and the use of appropriate hole transport materials such as N,N′-bis (naphthalen-1-yl)-N,N′-bis(phenyl) benzidine at ITO/organic interfaces can greatly improve the interfacial photo-stability. 相似文献