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661.
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Simone Alidori Filippo Cocchioni Giancarlo Falcioni Donatella Fedeli Gaia Emanuela Gioia Lobbia Marilena Mancini Maura Pellei Carlo Santini 《应用有机金属化学》2008,22(1):43-48
Triorganotin(IV) derivatives containing the anionic ligand bis(1‐methyl‐1H‐imidazol‐2‐ylthio)acetate [(S‐tim)2CHCO2]− were synthesized from the reaction between R3SnCl acceptors (R = Me and Ph) and the sodium salt of the ligand. Mono‐nuclear complexes of the type [(S‐tim)2CHCO2]SnR3 were obtained, which were fully characterized by elemental analyses and FT‐IR in the solid state, and by NMR (1H, 13C and 119Sn) spectroscopy and electrospray ionization mass in solution. The toxic effects shown by these compounds on trout erythrocyte components showed that the toxicity of the organotin(IV) complexes depends on the nature and on the lipophilicity of the substituents on the metal centre. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
663.
H. Moradpour Y. Heydarzade F. Darabi Ines G. Salako 《The European Physical Journal C - Particles and Fields》2017,77(4):259
A generalized version for the Rastall theory is proposed showing the agreement with the cosmic accelerating expansion. In this regard, a coupling between geometry and the pressureless matter fields is derived which may play the role of dark energy, responsible for the current accelerating expansion phase. Moreover, our study also shows that the radiation field may not be coupled to the geometry in a non-minimal way which represents that the ordinary energy-momentum conservation law is respected by the radiation source. It is also shown that the primary inflationary era may be justified by the ability of the geometry to couple to the energy-momentum source in an empty flat FRW universe. In fact, this ability is independent of the existence of the energy-momentum source and may compel the empty flat FRW universe to expand exponentially. Finally, we consider a flat FRW universe field by a spatially homogeneous scalar field evolving in potential \(\mathcal {V}(\phi )\), and study the results of applying the slow-roll approximation to the system which may lead to an inflationary phase for the universe expansion. 相似文献
664.
Barbara Rossi Paolo Verrocchio Gabriele Viliani Ines Mancini Graziano Guella Eveline Rigo Giorgina Scarduelli Gino Mariotto 《Journal of Raman spectroscopy : JRS》2009,40(4):453-458
The modifications to the vibrational spectra produced by inclusion into cyclodextrins on the vibrational spectra of of the non‐steroidal anti–inflammatory drug ibuprofen, by inclusion into cyclodextrins have been investigated by means of Raman scattering and numerical simulation. These changes are discussed and explained by comparison with the theoretical vibrational wavenumbersfrequencies and Raman intensities obtained by quantum and classical numerical simulations, disentangling the effects directly related to the complexation process, from those to be ascribed to non‐covalent dimerization of ibuprofen due to hydrogen bonding. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
665.
R.C. Mancini C.A. Iglesias S. Ferri A. Calisti R. Florido 《High Energy Density Physics》2013,9(4):731-736
The effect of the interference term in the electron broadening of the Li-like satellites to the Ar Heβ line has been investigated in the standard Stark broadening theory. Although the interference term has negligible or small effect on satellite lines with spectator electrons in n = 2 and n = 3 shells, it shows significant narrowing for lines with n = 4 spectator electrons. Nevertheless, the improved n = 4 satellite line shape makes a small difference in the emergent intensity distribution of the composite spectral feature. Accordingly, this change in line shape does not affect previous diagnosis of plasma conditions in Ar-doped ICF implosion cores. 相似文献
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667.
Katja Burek Dr. Joachim Dengler Dr. Franziska Emmerling Ines Feldmann Prof. Michael U. Kumke Dr. Julia Stroh 《ChemistryOpen》2019,8(12):1441-1452
The hydration process of Portland cement in a cementitious system is crucial for development of the high-quality cement-based construction material. Complementary experiments of X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and time-resolved laser fluorescence spectroscopy (TRLFS) using europium (Eu(III)) as an optical probe are used to analyse the hydration process of two cement systems in the absence and presence of different organic admixtures. We show that different analysed admixtures and the used sulphate carriers in each cement system have a significant influence on the hydration process, namely on the time-dependence in the formation of different hydrate phases of cement. Moreover, the effect of a particular admixture is related to the type of sulphate carrier used. The quantitative information on the amounts of the crystalline cement paste components is accessible via XRD analysis. Distinctly different morphologies of ettringite and calcium−silicate−hydrates (C−S−H) determined by SEM allow visual conclusions about formation of these phases at particular ageing times. The TRLFS data provides information about the admixture influence on the course of the silicate reaction. The dip in the dependence of the luminescence decay times on the hydration time indicates the change in the structure of C−S−H in the early hydration period. Complementary information from XRD, SEM and TRLFS provides detailed information on distinct periods of the cement hydration process. 相似文献
668.
It is usually believed that a picture of Quantum Mechanics in terms of true probabilities cannot be given due to the uncertainty relations. Here we discuss a tomographic approach to quantum states that leads to a probability representation of quantum states. This can be regarded as a classical‐like formulation of quantum mechanics which avoids the counterintuitive concepts of wave function and density operator. The relevant concepts of quantum mechanics are then reconsidered and the epistemological implications of such approach discussed. 相似文献
669.
670.
Verena I. Böhmer Prof. Wiktor Szymanski Keimpe-Oeds van den Berg Chantal Mulder Piermichele Kobauri Hugo Helbert Dr. Dion van der Born Friederike Reeβing Anja Huizing Dr. Marten Klopstra Douwe F. Samplonius Dr. Ines F. Antunes Jürgen W. A. Sijbesma Dr. Gert Luurtsema Prof. Wijnand Helfrich Dr. Ton J. Visser Prof. Ben L. Feringa Prof. Philip H. Elsinga 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(47):10871-10881
Since the seminal contribution of Rolf Huisgen to develop the [3+2] cycloaddition of 1,3-dipolar compounds, its azide–alkyne variant has established itself as the key step in numerous organic syntheses and bioorthogonal processes in materials science and chemical biology. In the present study, the copper(I)-catalyzed azide–alkyne cycloaddition was applied for the development of a modular molecular platform for medical imaging of the prostate-specific membrane antigen (PSMA), using positron emission tomography. This process is shown from molecular design, through synthesis automation and in vitro studies, all the way to pre-clinical in vivo evaluation of fluorine-18- labeled PSMA-targeting ‘F-PSMA-MIC’ radiotracers (t1/2=109.7 min). Pre-clinical data indicate that the modular PSMA-scaffold has similar binding affinity and imaging properties to the clinically used [68Ga]PSMA-11. Furthermore, we demonstrated that targeting the arene-binding in PSMA, facilitated through the [3+2]cycloaddition, can improve binding affinity, which was rationalized by molecular modeling. The here presented PSMA-binding scaffold potentially facilitates easy coupling to other medical imaging moieties, enabling future developments of new modular imaging agents. 相似文献