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991.
Diskin-Posner Y Patra GK Goldberg I 《Chemical communications (Cambridge, England)》2002,(13):1420-1421
Targeted synthesis of new supramolecular motifs of metalloporphyrins in crystals by a concerted mechanism of molecular recognition in three dimensions, aided by organic ligands, is presented; it involves induced assembly of [tetrakis(4-hydroxyphenyl)porphyrinato]zinc species by a combination of axial coordination through bridging bipyridyls and of lateral hydrogen bonding. 相似文献
992.
Bernas A Kumar N Mäki-Arvela P Laine E Holmbom B Salmi T Murzin DY 《Chemical communications (Cambridge, England)》2002,(10):1142-1143
Development of a new heterogeneous catalytic pathway for isomerization of linoleic acid to conjugated linoleic acids at mild reaction conditions over Ni/H-MCM-41 in a soluted system. 相似文献
993.
Kumar A Rai DK Rai SB 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2002,58(7):1379-1387
Laser induced excitation spectrum of the Nd3+ ions doped in oxyfluoroborate glass have been recorded. Stark components of different electronic states have been reported. Judd-Ofelt analysis has also been accomplished on the basis of ultraviolet-visible-near-infrared (UV-vis-NIR) absorption spectrum. Various radiative parameters such as electric dipole line strength, transition probability, life time of the various energy levels, branching ratio etc., have been estimated. 相似文献
994.
Kanungo M Srivastava DN Kumar A Contractor AQ 《Chemical communications (Cambridge, England)》2002,(7):680-681
A conductimetric reagentless immunosensor using the biospecific binding pair of goat antirabbit IgG and rabbit IgG has been designed and fabricated using poly (3,4-ethylenedioxythiophene) as the immobilization matrix-cumtransducer. 相似文献
995.
This paper reports a new solid support reagent that showed high degrees of selective molecular reactivity and molecular recognition in homo-functional reactions (reactions having similar reactive functionality in reactants and products). 相似文献
996.
Novel liquid-crystalline phases with layerlike organization 总被引:1,自引:0,他引:1
Cheng XH Das MK Diele S Tschierske C 《Angewandte Chemie (International ed. in English)》2002,41(21):4031-4035
997.
[reaction: see text] Single-electron oxidation has been employed to initiate heterogenerative cascade cyclization reactions that form polyether compounds under essentially neutral conditions. The reactions proceed through mesolytic benzylic carbon-carbon bond cleavages of homobenzylic ether-derived radical cations followed by intramolecular epoxonium ion formation, leading to further cyclizations. Both oligotetrahydrofuran and tetrahydropyran structures can be prepared by altering substrate topography. 相似文献
998.
999.
The dynamics of a single semiflexible filament under the action of a compressing force is simulated. We find that the filament folds asymmetrically with a folding length which depends only on the bending stiffness kappa and the applied force f. It is shown that this behavior can be attributed to the exponentially falling tension profile in the filament. While the folding time tau(0) depends on the initial configuration, the distance moved by the terminal point of the filament and the length of the fold scales as tau(1/2) at tau>tau(0) and is independent of the initial configuration. 相似文献
1000.
We show the existence of nonthreshold bound states of (p,q) string networks and D3-branes, preserving 1/4 of the full type-IIB supersymmetry, interpreted as string networks "dissolved" in D3-branes. We also explicitly write down the expression for the mass density of the system and discuss the extension of the construction to other Dp-branes. Differences in our construction of string networks with the ones interpreted as dyons in N = 4 gauge theories are also pointed out. 相似文献