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31.
32.
The paper outlines recent developments of an efficient computational micro-macro modeling of evolving anisotropies in metallic polycrystals. Main focus is put onto large strain deformation processes where the anisotropy is caused by developments of crystallographic texture. We construct a hybrid micro-macro framework that mixes ingredients of a purely macroscopic modeling with scale bridging operations of selected micromechanisms. On the micromechanical side, we develop a new algorithmic procedure to capture the crystal reorientation for evolving fcc and bcc textures based on a parametrization of rotations in the Rodigues space. The computational model provides a fast and robust method for the estimation of evolving textures. This computational tool for texture estimation is incorporated in a modular format into a micro-macro-model, where it governs the evolution of macrostructural tensors due to texture development. The general framework for the hybrid embedding is a purely phenomenological setting of anisotropic finite plasticity in the logarithmic strain space. The model provides an efficient and computationally handable two-scale approach for the prediction of effects caused by complex microstructural changes in polycrystals. The capability of the proposed method is demonstrated by means of representative numerical examples. (© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
33.
Dr. Linghao Yan Ilona Pohjavirta Benjamin Alldritt Prof. Peter Liljeroth 《Chemphyschem》2019,20(18):2297-2300
On-surface metal-organic coordination provides a promising way for synthesizing different two-dimensional lattice structures that have been predicted to possess exotic electronic properties. Using scanning tunneling microscopy (STM) and spectroscopy (STS), we studied the supramolecular self-assembly of 9,10-dicyanoanthracene (DCA) molecules on the Au(111) surface. Close-packed islands of DCA molecules and Au-DCA metal-organic coordination structures coexist on the Au(111) surface. Ordered DCA3Au2 metal-organic networks have a structure combining a honeycomb lattice of Au atoms with a kagome lattice of DCA molecules. Low-temperature STS experiments demonstrate the presence of a delocalized electronic state containing contributions from both the gold atom states and the lowest unoccupied molecular orbital of the DCA molecules. These findings are important for the future search of topological phases in metal-organic networks combining honeycomb and kagome lattices with strong spin-orbit coupling in heavy metal atoms. 相似文献
34.
Michnik Anna Kiełboń Agnieszka Duch Klaudia Sadowska-Krępa Ewa Pokora Ilona 《Journal of Thermal Analysis and Calorimetry》2022,147(12):6739-6743
Journal of Thermal Analysis and Calorimetry - The results of studies of physiological fluids by differential scanning calorimetry (DSC) for the purpose of diagnosis and monitoring of diseases are... 相似文献
35.
Regina J. Patinvoh Elisabeth Feuk-Lagerstedt Magnus Lundin Ilona Sárvári Horváth Mohammad J. Taherzadeh 《Applied biochemistry and biotechnology》2016,180(7):1401-1415
Chicken feathers are available in large quantities around the world causing environmental challenges. The feathers are composed of keratin that is a recalcitrant protein and is hard to degrade. In this work, chicken feathers were aerobically pretreated for 2–8 days at total solid concentrations of 5, 10, and 20 % by Bacillus sp. C4, a bacterium that produces both α- and β-keratinases. Then, the liquid fraction (feather hydrolysate) as well as the total broth (liquid and solid fraction of pretreated feathers) was used as substrates for biogas production using anaerobic sludge or bacteria granules as inoculum. The biological pretreatment of feather waste was productive; about 75 % of feather was converted to soluble crude protein after 8 days of degradation at initial feather concentration of 5 %. Bacteria granules performed better during anaerobic digestion of untreated feathers, resulting in approximately two times more methane yield (i.e., 199 mlCH4/gVS compared to 105 mlCH4/gVS when sludge was used). Pretreatment improved methane yield by 292 and 105 % when sludge and granules were used on the hydrolysate. Bacteria granules worked effectively on the total broth, yielded 445 mlCH4/gVS methane, which is 124 % more than that obtained with the same type of inoculum from untreated feather. 相似文献
36.
Kazimieras Anusevičius Ilona Jonuškienė Birutė Sapijanskaitė Kristina Kantminienė Vytautas Mickevičius 《Research on Chemical Intermediates》2016,42(9):6975-6990
N-Substituted 7-amino-4-methyl-2H-chromen-2-ones containing one or two functionalized azole or azine moieties were synthesized. The structures of all synthesized compounds were confirmed by IR, 1H NMR, and 13C NMR spectroscopy. Some of the synthesized compounds exhibited weak antibacterial activity against Rhizobium radiobacter, Escherichia coli, and Xanthomonas campestris. 相似文献
37.
We prove that certain means of the quadratical partial sums of the two‐dimensional Vilenkin‐Fourier series are uniformly bounded operators from the Hardy space to the space for We also prove that the sequence in the denominator cannot be improved. 相似文献
38.
Alla Zablotskaya Izolda Segal Mikhail Maiorov Elmars Blums Ilona Domracheva 《Journal of magnetism and magnetic materials》2009,321(10):1428-1432
We present the results of the interaction of iron oxide nanoparticles with some biologically active surfactants, namely, oleic acid and cytotoxic alkanolamine derivatives. Physico-chemical properties, as magnetization, magnetite concentration and particle diameter, of the prepared magnetic samples were studied. The nanoparticle size of 11 nm for toluene magnetic fluid determined by TEM is in good agreement with the data obtained by the method of magnetogranulometry. In vitro cytotoxic effect of water-soluble nanoparticles with different iron oxide:oleic acid molar ratio were revealed against human fibrosarcoma and mouse hepatoma cells. In vivo results using a sarcoma mouse model showed observable antitumor action. 相似文献
39.
Jolanta Rousseau Vilija Kriščiūnienė Ilona Rimkevičiūtė Cyril Rousseau Virginė Amankavičienė Algirdas Šačkus Arnaud Tatibouët Patrick Rollin 《Monatshefte für Chemie / Chemical Monthly》2009,140(3):339-348
Abstract Modular conditions for the formation of thioureas or pyrimidine-4-one-2-thiones connected to the benzo[b]thiophene, benzene and indole structures were performed. A benzo[b]thiophene isothiocyanate derivative was used as a model to study the condensation with simple aromatic amines and amino-l-sorbose derivative. The construction of pyrimidine-4-one-2-thiones using basic conditions afforded efficiently new heterocyclic
aromatics, which were further transformed using the alkylated sulfur as a leaving group in palladium-catalyzed cross-coupling
reactions.
Graphical abstract
相似文献
40.
In this tutorial review we summarize the standard approaches to describe aerosol formation from atmospheric vapours and subsequent growth - with a particular emphasis on the interplay between equilibrium thermodynamics and non-equilibrium transport. We review the use of thermodynamics in describing phase equilibria and formation of aerosol particles from supersaturated vapour via nucleation. We also discuss the kinetics of cluster formation and transport phenomena, which are used to describe dynamic mass transport between the gaseous and condensed phases in a non-equilibrium system. Finally, we put these theories into the context of atmospheric observations of aerosol formation and growth. 相似文献