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81.
82.
An analytic method is presented for calculating strong motion spectra and response to arbitrary input in layered media. The method is based on the removal of secular terms at resonance of the equations with polynomial non-linearity. The non-linear effects are introduced by the frequency shifts calculated from the secular term according to the method by Millman and Keller. The procedure, through a convenient parametrizarion of the frequency, allows one to deal with linear equations. This possibility permits the extension of the method to multilayer systems by the use of transfer matrices. The response to an arbitrary input motion is obtained from the response spectrum in the frequency domain by the use of (Fast) Fourier Transform. 相似文献
83.
84.
smail
zdemir Yetkin Gk Nevin Gürbüz Engin etinkaya Bekir etinkaya 《Journal of heterocyclic chemistry》2005,42(2):303-306
The in situ prepared three component system Pd(OAc)2, 1,3‐dialkylbenzimidazolium halides ( 1a‐e ) and t‐BuOK catalyses quantitatively the Suzuki cross‐coupling of deactivated aryl chloride substrates. 1,3‐Dialkylbenzimidazolium salts ( 1a‐e ) were characterized by conventional spectroscopic methods and elemental analyses. 相似文献
85.
Using a rigid xanthene scaffold, a series of boradiazaindacene derivatives were synthesized. In some of these compounds, two boradiazaindacene derivatives were placed cofacially, resulting in significant inter-chromophoric interactions, including excimer emission. A simple modification of boradiazaindacene structure leads to formation of an ICT dye, which has distinct spectral properties. Energy transfer between two BODIPY dyes was demonstrated as well. In addition, the spectral properties of ICT dye can be modulated by the addition of the acid leading to an acid switchable energy transfer cassette. 相似文献
86.
[reaction: see text] Acylcyclopropanemethanol tosylates undergo rapid ring opening at room temperature by the action of lithium telluride to produce the enolate of a homoallylic ketone. The enolate can be protonated to yield the corresponding ketone or treated with benzaldehyde to give the aldol product with good syn or anti diastereoselectivity depending on the conditions. 相似文献
87.
Neslihan Saki Engin U. Akkaya 《Journal of inclusion phenomena and macrocyclic chemistry》2005,53(3-4):269-273
A novel dimeric calixpyrrole has been synthesized. The dimer forms stable complexes with p-nitrophenolate ion with a concomitant reduction in extinction coefficient. The chromogenic anion is displaced by the addition of various anions like fluoride and acetate. Effective optical sensing of these anions is accomplished using the calixpyrrole dimer. 相似文献
88.
Ismail Özdemir Nevin Gürbüz Yetkin Gök Bekir Çetinkaya Engin Çetinkaya 《Transition Metal Chemistry》2005,30(3):367-371
Six rhodium–carbene complexes (2a–f) have been prepared and the new compounds characterized by C, H, N analyses, 1H-n.m.r. and 13C-n.m.r. Phenylboronic acid reacts with aldehydes in the presence of a catalytic amount of rhodium(I)–carbene complex, RhCl(COD)(1,3-dialkylbenzimidazolidin-2-ylidene), (2a–f), to give the corresponding aryl secondary alcohols in good yields. 相似文献
89.
A novel distyryl-substituted boradiazaindacene (BODIPY) dye displays interesting properties as a sensitizer in DSSC systems, opening the way to further exploration of structure-efficiency correlation within this class of dyes. 相似文献
90.
Performance of a fast fiber based UV/Vis multiwavelength detector for the analytical ultracentrifuge
Holger M. Strauss Engin Karabudak Saroj Bhattacharyya Andreas Kretzschmar Wendel Wohlleben Helmut Cölfen 《Colloid and polymer science》2008,286(2):121-128
The optical setup and the performance of a prototype UV/Vis multiwavelength analytical ultracentrifuge (MWL-AUC) is described
and compared to the commercially available Optima XL-A from Beckman Coulter. Slight modifications have been made to the optical
path of the MWL-AUC. With respect to wavelength accuracy and radial resolution, the new MWL-AUC is found to be comparable
to the existing XL-A. Absorbance accuracy is dependent on the light intensity available at the detection wavelength as well
as the intrinsic noise of the data. Measurements from single flashes of light are more noisy for the MWL-AUC, potentially
due to the absence of flash-to-flash normalization in the current design. However, the possibility of both wavelength and
scan averaging can compensate for this and still give much faster scan rates than the XL-A. Some further improvements of the
existing design are suggested based on these findings. 相似文献