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991.
The large deformation of a cantilever beam under point load at the free tip is investigated by an analytic method, namely the homotopy analysis method (HAM). The explicit analytic formulas for the rotation angle at the free tip are given, which provide a convenient and straightforward approach to calculate the vertical and horizontal displacements of a cantilever beam with large deformation. These explicit formulas are valid for most practical problems, thus providing a useful reference for engineering applications. The corresponding Mathematica code is given in the Appendix. 相似文献
992.
Zhuoyu Ji Hongxiang Li Yaling Liu Wenping Hu 《Applied Physics A: Materials Science & Processing》2008,91(2):301-303
In this paper we propose a method for the integration of the synthesis of silver-tetracyanoquinodimethane (AgTCNQ) and the
fabrication of its devices within one step. The method was performed by electroplating Ag between gold coplanar micro-gap
electrodes in tetracyanoquinodimethane (TCNQ) solution. As soon as silver was electrochemically dissolved in the TCNQ solution,
it immediately reacted with TCNQ to form AgTCNQ and then deposited between Au gap electrodes. With the continuing of the reaction,
the Au micro-gap electrodes were connected by AgTCNQ to form Au/AgTCNQ/Au coplanar gap devices. With this electroplating technique,
series gap devices of AgTCNQ were fabricated, and the devices exhibited switching phenomena with good reproducibility. This
method integrated the synthesis of AgTCNQ and the fabrication of its devices within a single step, and should be also inspirable
for other charge transfer complexes.
PACS 81.05.Hd; 81.20.Ka; 82.45.Aa; 82.45.Qr 相似文献
993.
Spatial patterns of the uncatalyzed bromate – catechol – sulfuric acid system in a thin fluid layer were observed. A mixture of dots, strips and circles was formed by interaction of chemical reaction, diffusion and hydrodynamic instabilities. 相似文献
994.
995.
Zhi‐guo Zhang Ji‐bing Yuan Huai‐jun Tang Hao Tang Li‐na Wang Ke‐Li Zhang 《Journal of polymer science. Part A, Polymer chemistry》2009,47(1):210-221
A novel nonconjugated copolymer (PVKEu) with carbazole segments and phenanthroline [Eu(β‐diketonate)3] moieties was synthesized via free radical copolymerization, and characterized by FTIR, 1H NMR spectroscopy, GPC, ICP, and elemental analysis. The copolymer exhibited good solubility, as well as good thermal stability and high glass transition temperature. The photoluminescence (PL) of this polymer in solution and in solid film has been studied. A multi‐layer device with the configuration of ITO/PEDOT: PSS (40 nm)/PVKEu (70 nm)/BCP (15 nm)/AlQ3 (30 nm)/LiF/Al exhibited nearly monochromatic red emission at 615 nm and voltage‐independent spectral stability. Our results suggest that enhancing the ligand‐mediated energy transfer between the matrix polymer and europium complex is a potential method to improve the electroluminescence performance of the Eu‐chelated polymers. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 210–221, 2009 相似文献
996.
997.
Jin-Hua Cai Jin-Wang Huang Ping Zhao Yuan-Jian Ye Han-Cheng Yu Liang-Nian Ji 《Journal of Sol-Gel Science and Technology》2009,50(3):430-436
Three types of novel silica-metalloporphyrins hybrid materials, Si-S-APTCPPFe, Si-S-APTCPPMn and Si-S-APTCPPCo, were prepared
at room temperature by sol–gel method involving a thiol-ene polymerization reaction of 5-(4-allyloxy)phenyl-10,15,20-tri(4-chlorophenyl)porphyrin
(APTCPP) with 3-mercaptopropyltrimethoxysilane (MPS). The hybrid materials were characterized by XRD, SEM, FT–IR, UV–Vis and
TG, and were investigated as catalysts for the aerobic oxidation of cyclohexane. It is found that these hybrid materials are
more efficient catalysts than the analogous non-supported metalloporphyrins for cyclohexane hydroxylation in metalloporphyrin–O2–ascrobate system and the metal ion in the porphyrins significantly affected the catalytic efficiencies of these hybrid materials. 相似文献
998.
Li‐Ming Tang Ji‐Qian Wu Yi‐Qun Duan Li Pan Yan‐Guo Li Yue‐Sheng Li 《Journal of polymer science. Part A, Polymer chemistry》2008,46(6):2038-2048
Five novel vanadium(III) complexes [PhN = C(R2)CHC(R1)O]VCl2(THF)2 ( 4a : R1 = Ph, R2 = CF3; 4b : R1 = t‐Bu, R2 = CF3; 4c : R1 = CF3, R2 = CH3; 4d : R1 = Ph, R2 = CH3; 4e : R1 = Ph, R2 = H) have been synthesized and characterized. On activation with Et2AlCl, all the complexes, in the presence of ethyl trichloroacetate (ETA) as a promoter, are highly active precatalysts for ethylene polymerization, and produce high molecular weight and linear polymers. Catalyst activities more than 16.8 kg PE/mmolV h bar and weight‐average molecular weights higher than 173 kg/mol were observed under mild conditions. The copolymerizations of ethylene and norbornene or 1‐hexene with the precatalysts were also explored, which leads to high molecular weight copolymers with high comonomer incorporation. Catalyst activity, comonomer incorporation, and polymer molecular weight as well as polydispersity index can be controlled over a wide range by the variation of precatalyst structure and the reaction parameters such as Al/V molar ratio, comonomer feed concentration, and polymerization temperature. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2038–2048, 2008 相似文献
999.
Nai Yun Ji Xiao Ming Li Chuan Ming Cui Bin Gui Wang 《中国化学快报》2007,18(8):957-959
Two new brominated diterpenes,namely,laurendecumtriol and 11-deacetylpinnaterpene C,were isolated and identified from the marine red alga Laurencia decumbens.Their structures were established on the basis of various NMR spectroscopic techniques and HR-ESI-MS analyses. 相似文献
1000.
Gang Liu Chunping Liu Lin Sun Rongjun Qu Hou Chen Chunnuan Ji 《Chemistry of Heterocyclic Compounds》2007,43(10):1290-1300
A series of N-substituted 4-amino-6,7,8-trimethoxyquinazoline derivatives has been synthesized from 4-chloro-6,7,8-trimethoxyquinazoline
and aryl (or benzyl) amines using 2-propanol as a solvent. The starting material 4-chloro-6,7,8-trimethoxyquinazoline has
been synthesized from natural gallic acid by a novel route. Their structures have been verified by elemental analysis and
IR, 1H, and 13C NMR spectroscopy. The title compounds have been evaluated for their in vitro antiproliferative activities against some cancer
cells by the MTT method. Unfortunately, most of the compounds tested have exhibited a weaker anticancer activity than the
reference standard drug PD153035.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, 1521–1531, September, 2007. 相似文献