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991.
Reactions between the ethylene groups in the backbone of conjugated polymers under UV illumination and heat treatment result in the cross‐linking of the main polymer chains. The cross‐linking leads to two simultaneous results in the polymer: excellent solvent resistance and increased bandgap. Using this reaction, three‐color polymer light‐emitting diodes (PLEDs) with a multi‐layer structure can be easily realized by a dry photo‐pattern in an active‐gas‐free environment. Multi‐layer blue devices with dramatically enhanced efficiency can also be achieved conveniently.
992.
Grignard reagents were generated from magnesium and organic iodides in the ionic liquid n-butylpyridinium tetrafluoroborate, [bpy][BF4], and they showed different reactivity from classical Grignard reagents in organic solvents. 相似文献
993.
Oscillation criteria for second order forced ordinary differential equations with mixed nonlinearities 总被引:1,自引:0,他引:1
Yuan Gong Sun James S.W. Wong 《Journal of Mathematical Analysis and Applications》2007,334(1):549-560
We present new oscillation criteria for the second order forced ordinary differential equation with mixed nonlinearities:
994.
SYNTHESIS AND OPTICAL PROPERTIES OF POLY (THIENYLACETYLENES)* 总被引:1,自引:0,他引:1
3 -Ethynyl-4-(trimethylsilyl)thiophene (1a) and 3 -ethynyl-4-bromothiophene (1 b ) selectivelyundergo acetylene polymerizations in the presence of the MoCl_5- and WCl_6-Ph_3SiH catalysts to give soluble,high-molecular-weight poly(thienylacetylenes) (2) (M_w up to 602000) in high yields (up to 100%). Lighttransmission spectra of THF solutions of 2 continuously red-shift with increasing concentration. Theconcentratochromism shows a logarithmic concentration dependence; that is, the optical transitions of 2 arepredictably tunable by simply changing their concentrations. 相似文献
995.
Lin HW Lin LY Chen YH Chen CW Lin YT Chiu SW Wong KT 《Chemical communications (Cambridge, England)》2011,47(27):7872-7874
A new D-π-A molecule (TPDCDTS) adopting coplanar diphenyl-substituted dithienosilole as a central π-bridge of triphenylamine (donor) and dicyanovinylene (acceptor) has been synthesized as donor material for small molecule organic solar cells (SMOSC) incorporating C(70) as an acceptor showed an appreciable power conversion efficiency of 3.82%. 相似文献
996.
The existence and uniqueness of a bounded solution are shown for the linear equation in infinite matrix where A is strictly diagonally dominant and b is bounded. 相似文献
997.
On treatment with diphenyldichloromethane or anisal chloride in the presence of acetone and aqueous sodium hydroxide, pyridine undergoes condensation and ring cleavage to yield the enamine Schiff bases 1,1-diphenyl-2-azadeca-1,3Z,5Z,7E-tetraen-9-one (1) and 1-(4-methoxyphenyl)-2-azadeca-1E,3Z,5Z,7E-tetraen-9-one (7). The reaction proceeds through attack of acetonyl carbanion on the initially formed bis-pyridinium salt, followed by ring scission with elimination of one equivalent of pyridine. The structure and stereochemistry of the 2-azatetraene (1) was confirmed by X-ray crystallography. 相似文献
998.
X.Y. Chen K.H. Wong C.L. Mak J.M. Liu X.B. Yin M. Wang Z.G. Liu 《Applied Physics A: Materials Science & Processing》2002,74(5):703-706
Selective growth of single-oriented (110), (100) and (111) MgO films on Si (100) substrates without buffer layers was obtained
via a two-step method by pulsed laser deposition. It was found that the orientation of the films was determined at the initial
deposition stage by the substrate temperature only. The ambient pressure during deposition, the laser fluence and the etching
of the Si substrates have no apparent effect on the orientation of the films, but affect their crystalline quality. Under
the present deposition conditions, the surfaces of all three different single-oriented films were very smooth and devoid of
any particulates.
Received: 23 January 2001 / Accepted: 6 June 2001 / Published online: 2 October 2001 相似文献
999.
Lanthanide metal organic frameworks (MOFs), Eu(BTC) and TbEu(BTC) were assessed to follow uptake of deoxynucleotide triphosphate (dNTPs) in loop mediated isothermal amplification (LAMP) using BST2.0. dNTPs could be determined below 150 μM. A ratiometic measurement of Tb3+:Eu3+ fluorescence in TbEu(BTC) gave a limit of detection of 2.08 μM for dNTPs. dNTP uptake slowed above 8 mM Mg2+. This correlated with end-point and real-time LAMP, using PicoGreen and SYBR green respectively. For the P.Mal-Lau 18S rRNA primer set, with P. malariae a detection limit of 102.5 copies was obtained. Cross reactivity between P. malariae and P. knowlesi was shown with 18S rRNA primer sets. 相似文献
1000.
Ng Wei Wuen Thiam Hui San Pang Yean Ling Lim Yun Seng Wong Jianhui 《Journal of Solid State Electrochemistry》2023,27(6):1477-1492
Journal of Solid State Electrochemistry - Getting the direct methanol fuel cell (DMFC) closer to mass production requires the creation of a high-performance and long-lasting proton exchange... 相似文献