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101.
Dr. Charlie L. Hall Dr. Iryna Andrusenko Dr. Jason Potticary MSc Siyu Gao MSc Xingyu Liu Dr. Werner Schmidt Prof. Noa Marom Dr. Enrico Mugnaioli Prof. Mauro Gemmi Prof. Simon R. Hall 《Chemphyschem》2021,22(15):1631-1637
Herein we demonstrate the prowess of the 3D electron diffraction approach by unveiling the structure of terrylene, the third member in the series of peri-condensed naphthalene analogues, which has eluded structure determination for 65 years. The structure was determined by direct methods using electron diffraction data and corroborated by dispersion-inclusive density functional theory optimizations. Terrylene crystalizes in the monoclinic space group P21/a, arranging in a sandwich-herringbone packing motif, similar to analogous compounds. Having solved the crystal structure, we use many-body perturbation theory to evaluate the excited-state properties of terrylene in the solid-state. We find that terrylene is a promising candidate for intermolecular singlet fission, comparable to tetracene and rubrene. 相似文献
102.
Cebrián-Losantos B Krokhin AA Stepanenko IN Eichinger R Jakupec MA Arion VB Keppler BK 《Inorganic chemistry》2007,46(12):5023-5033
The osmium(III) complex [(DMSO)2H][trans-OsIIICl4(DMSO)2] (1) has been prepared via stepwise reduction of OsO4 in concentrated HCl using N2H(4).2HCl and SnCl(2).2H2O in DMSO. 1 reacts with a number of azole ligands, namely, indazole (Hind), pyrazole (Hpz), benzimidazole (Hbzim), imidazole (Him), and 1H-1,2,4-triazole (Htrz), in organic solvents, affording novel complexes (H2ind)[OsIIICl4(Hind)(DMSO)] (2), (H2pz)[OsIIICl4(Hpz)(DMSO)] (3), (H2bzim)[OsIIICl4(Hbzim)(DMSO)] (4), (H2im)[OsIIICl4(Him)(DMSO)] (6), and (H2trz)[OsIIICl4(Htrz)(DMSO)] (7), which are close analogues of the antimetastatic complex NAMI-A. Metathesis reaction of 4 with benzyltriphenylphosphonium chloride in methanol led to the formation of (Ph3PCH2Ph)[OsIIICl4(Hbzim)(DMSO)] (5). The complexes were characterized by IR, UV-vis, ESI mass spectrometry, 1H NMR spectroscopy, cyclic voltammetry, and X-ray crystallography. In contrast to NAMI-A, 2-4, 6, and 7 are kinetically stable in aqueous solution and resistant to hydrolysis. Surprisingly, they show reasonable antiproliferative activity in vitro in two human cell lines, HT-29 (colon carcinoma) and SK-BR-3 (mammary carcinoma), when compared with analogous ruthenium compounds. Structure-activity relationships and the potential of the prepared complexes for further development are discussed. 相似文献
103.
The present work is devoted to the investigation of the contact interaction of the faces of cracks located in the homogeneous, isotropic, linearly elastic 3-D medium under a harmonic loading. The Signorini contact constraints are imposed and the friction is governed by the Coulomb law. The problem is solved by the method of the boundary integral equations with the use of the iterative procedure. The dependence of the stress intensity factors on the friction coefficient and parameters of the incident wave parameters (frequency, angle of incidence, etc.) is studied. Numerical results are compared with those obtained without allowance for the contact interaction. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
104.
105.
Andriy Kytsya Liliya Bazylyak Paul Simon Iryna Zelenina Iryna Antonyshyn 《国际化学动力学杂志》2019,51(4):266-273
The kinetics of formation of silver nanoparticles consisting of nearly 300 metal atoms is investigated, which were prepared by reduction of silver nitrate with hydrazine in ethylene glycol at 25°C without any stabilizer other than the glycol solvent. The resulting sigmoidal kinetic curves are analyzed by using the 1997 Finke–Watzky two-step mechanism of slow continuous nucleation with subsequent fast autocatalytic surface growth. The kinetics of homogeneous nucleation of metal nanoparticles was analyzed using the assumption about the stepwise adjunction of precursor and the quasi steady-state approximation. The equations were proposed to calculate the concentration of the formed metal nanoparticles and their mean size from the experimentally determined values of the Finke–Watzky rate constants. It is shown that a stepwise nucleation process can be described in the terms of the catalytically effective nucleus concept and that the number of atoms in the catalytically effective nucleus can be estimated. 相似文献
106.
Arad Lang Sylwia Mijowska Iryna Polishchuk Simona Fermani Giuseppe Falini Alexander Katsman Frédéric Marin Boaz Pokroy 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(70):16860-16868
Carbohydrates, along with proteins and peptides, are known to represent a major class of biomacromolecules involved in calcium carbonate biomineralization. However, in spite of multiple physical and biochemical characterizations, the explicit role of saccharide macromolecules (long chains of carbohydrate molecules) in mineral deposition is not yet understood. In this study, we investigated the influence of two common acidic monosaccharides (MSs), the two simplest forms of acidic carbohydrates, namely glucuronic and galacturonic acids, on the formation of calcite crystals in vitro. We show here that the size, morphology, and microstructure of calcite crystals are altered when they are grown in the presence of these MSs. More importantly, these MSs were found to become incorporated into the calcite crystalline lattice and induce anisotropic lattice distortions, a phenomenon widely studied for other biomolecules related to CaCO3 biomineralization, but never before reported in the case of single MSs. Changes in the calcite lattice induced by MSs incorporation were precisely determined by high-resolution synchrotron powder X-ray diffraction. We believe that the results of this research may deepen our understanding of the interaction of saccharide polymers with an inorganic host and shed light on the implications of carbohydrates for biomineralization processes. 相似文献
107.
Shum Andrew D. Liu Christopher P. Lim Wei Han Parkinson Dilworth Y. Zenyuk Iryna V. 《Transport in Porous Media》2022,144(3):715-737
Transport in Porous Media - X-ray computed tomography (CT) is increasingly used to characterize the morphology of water distribution in gas diffusion layers (GDLs) for polymer electrolyte fuel cell... 相似文献
108.
We explore differences between canonical and grand canonical ensembles of 500–2000 free electrons confined in a spherical well with a radius from 1.2 to 2 nm. The averaged occupation numbers of the electronic energy levels and their variances are calculated. For isolated Ag and Au particles, the sum of the variances of all occupation numbers differs from the corresponding bulk-metal value by a factor of 0.005 to 2. 相似文献
109.
Dariya Semenyshyn Iryna Typilo Olha Sereda Oleg Dolomanov Helen Stoeckli-Evans 《ChemInform》2012,43(50):no-no
Good quality single crystals of the title compound are obtained by reaction of H4[Mo(CN)8] with the rare earth carbonates. 相似文献
110.
An experimental study and analysis is presented of the acoustic properties of Sn2P2(Se0.28S0.72)6 ferroelectric crystals. Complete matrices of elastic stiffness and compliance as well as characteristic acoustic slowness surfaces have been obtained. The directions of propagation and polarisation of the slowest acoustic waves were determined. It was found that the elastic properties and the acoustic wave velocities for Sn2P2(Se0.28S0.72)6 and Sn2P2S6 crystals are almost the same at room temperature. 相似文献