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991.
Synthesis,spectral, theoretical studies and in vitro antimicrobial activities of novel diphenyltin(IV) complexes of Schiff bases derived from phenacylamine 下载免费PDF全文
Gökhan Şirikci Nilgün Ancın Selma Gül Öztaş Gülgün Yenişehirli Nurşen Altuntaş Öztaş 《应用有机金属化学》2014,28(7):537-544
A series of new diphenyltin(IV) complexes of the type Ph2SnL (L1: N‐phenacyl‐5‐bromosalicylideneimine, Ph2SnL1; L2: N‐phenacyl‐3,5‐dichlorosalicylideneimine, Ph2SnL2; L3: N–phenacyl‐4‐methoxysalicylideneimine, Ph2SnL3) were synthesized and characterized by elemental analysis, IR, 1H, 13C, 119Sn NMR spectroscopy and mass spectrometry techniques. The C―Sn―C angles in the complexes were calculated using equations with the 1J(117/119Sn―13C) values from 13C NMR spectra. The possible structures, NMR and electronic properties of the studied molecules were calculated through density functional theory and results compared with experimental data. All the complexes were found to be mildly active against several microorganisms and some fungi. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
992.
Amir R. Ali Tindaro Ioppolo Volkan Ötügen Marc Christensen Duncan MacFarlane 《Journal of polymer science. Part A, Polymer chemistry》2014,52(3):276-279
The detection of electric field by monitoring the optical whispering gallery mode shifts of polymeric microspheres is demonstrated. Two types of spheres are considered; (i) a polydimethylsiloxane (PDMS) sphere with 60 parts base silicon elastomer-to-1 part polymer curing agent by volume and; (ii) a silica sphere coated with a PDMS (uncured) base. The optical mode shifts are caused by perturbations to the resonator morphology induced by electrostriction effect in the presence of an external electric field. Preliminary experiments show that the latter microsphere yields higher sensitivity (0.027 pm/V m−1) with a measurement precision of ∼1.8 V/m. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 276–279 相似文献
993.
BJÖRN O. ROOS 《Molecular physics》2013,111(1-2):87-91
Results are presented from a theoretical study of the × 6Σ+, A 6Σ+ and 6Δ electronic states of CrH using multiconfiguration second-order perturbation theory in the multi-state formalism (MS-CASPT2). It is shown that the results for the spectroscopic constants and radiative lifetimes for the A state are in agreement with experiment and an earlier multireference configuration interaction study only if the two close lying × and A states are allowed to interact at a level of approximation that includes dynamic correlation. 相似文献
994.
A rapid and specific proton magnetic resonance (PMR) spectroscopic method was developed for determining primidone in tablets. Maleic acid was used as the internal standart and DMSO-d6 served as the PMR solvent. 相似文献
995.
Ultraviolet/visible photon transmission measurements were applied to study liquid crystal phase transitions in the binary BOPDOB-BOPOOB mixture. A sequence exhibiting a new reentrant, namely isotropic-nematic-smectic A-C-A as temperature is lowered, is identified. For the smectic A-C transition, the critical exponent g is seen to cross over from the mean-field 0.501 - 0.008 to the helium-like 0.336 - 0.012 as the transition is approached. The reentrant C-A transition is first-order, signalling a tricritical point in the phase diagram. 相似文献
996.
INTRODUCTION The information regarding the experimental values of K and L X-ray intensity ratios are important due to its wide use in many areas of basic and applied science and non-destructive elemental analysis of materials using the X-ray fluorescence technique. Chemical effects on K and L X-ray intensity ratios are not very well known, but they are an interesting subject. Some studies [1–4] addressing chemical effects on the Kβ/Kα intensity ratios have been made. We investigated chemical effects [5–7] and alloying effects [8] on the Kβ/Kα intensity ratios, and measured Kβ/Kα intensity ratios following radioactive decay and photoionisation [9]. But there are few studies addressing chemical effects on the L X-rays intensity ratios. Iihara et a1.[10] examined chemical effects on chromium L X-rays. 相似文献
997.
A new application of the Paul wavelet algorithm was presented to determine the refractive index dispersion of a dielectric film from transmittance spectrum in the visible and near infrared region. The developed algorithm was tested by simulated data and experimentally applied to a sample of mica. The obtained refractive index dispersion determined by the Paul wavelet algorithm was compared with the refractive index values determined by the envelope and fringe counting methods, and also with the established result. It was shown that the degree of the Paul wavelet has a major effect on the outcome of a refractive index determination. The noise immunity of the presented method was shown by the simulation study. 相似文献
998.
A series of Lewis bases were screened for Abramov-type phosphine additions to aldehydes. A novel phosphine oxide aziridinyl phosphonate POAP-A was found to be better than the others in forming the product in 96% yield and with 42% ee. The absolute configuration of the newly synthesized POAP Lewis bases was determined by single-crystal X-ray analysis. 相似文献
999.
1000.
T. SCHÖNFELD 《International Journal of Computational Fluid Dynamics》2013,27(3-4):363-391
SUMMARY The local grid refinement technique is incorporated into a finite volume program that solves the three-dimensional compressible Euler equations. The underlying idea is to improve the solution accuracy in domains of dominating physical flow features, thus avoiding a global fine mesh to resolve most of the smooth flow. An unstructured data system is introduced to manage point enrichment on multiple refinement levels for structured meshes of hexahedral cells. Grid adaption is utilized to cluster points automatically in domains of interest. The multi-block formulation permits the application of the refinement method to various external flow configurations. 相似文献