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131.
Sorin Popa 《Inventiones Mathematicae》2006,165(2):409-451
We prove that any isomorphism θ:M0≃M of group measure space II1 factors,
,
, with G0 an ICC group containing an infinite normal subgroup with the relative property (T) of Kazhdan-Margulis (i.e. G0w-rigid) and σ a Bernoulli action of some ICC group G, essentially comes from an isomorphism of probability spaces which conjugates
the actions with respect to some identification G0≃G. Moreover, any isomorphism θ of M0 onto a “corner” pMp of M, for p∈M an idempotent, forces p=1. In particular, all group measure space factors associated with Bernoulli actions of w-rigid ICC groups have trivial fundamental
group and any isomorphism of such factors comes from an isomorphism of the corresponding groups. This settles a “group measure
space version” of Connes rigidity conjecture, shown in fact to hold true in a greater generality than just for ICC property
(T) groups. We apply these results to ergodic theory, establishing new strong rigidity and superrigidity results for orbit
equivalence relations. 相似文献
132.
Sorin Dumitrescu 《Monatshefte für Mathematik》2010,19(2):145-154
We study local automorphisms of holomorphic Cartan geometries. This leads to classification results for compact complex manifolds admitting holomorphic Cartan geometries. We prove that a compact Kähler Calabi–Yau manifold bearing a holomorphic Cartan geometry of algebraic type admits a finite unramified cover which is a complex torus. 相似文献
133.
Florin A. Radu Iuliu Sorin Pop Sabine Attinger 《Numerical Methods for Partial Differential Equations》2010,26(2):320-344
In this article, we analyze an Euler implicit‐mixed finite element scheme for a porous media solute transport model. The transporting flux is not assumed given, but obtained by solving numerically the Richards equation, a model for subsurface fluid flow. We prove the convergence of the scheme by estimating the error in terms of the discretization parameters. In doing so we take into account the numerical error occurring in the approximation of the fluid flow. The article, is concluded by numerical experiments, which are in good agreement with the theoretical estimates. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2010 相似文献
134.
135.
Sorin Staicu Ilie G. Dinulescu Filip Chiraleu Margaret Avram 《Journal of organometallic chemistry》1976,117(4):385-394
The synthesis of ortho-substituted diphenylacetylenes and their behaviour toward dichlorobis(benzonitrile)palladium(II) are described. The influence of steric factors on the oligomerization is discussed. 相似文献
136.
Preconcentration by dithiocarbamate extraction into 2-ethylhexyl acetate for simultaneous determination of trace elements in natural water is described. After 250-fold concentration, the organic phase is used directly for inductively-coupled plasma atomic emission spectrometry. Thirteen elements (As, Se, Mo, Zn, Cd, Ni, Co, Sn, Fe, Cr(VI), Pb, V and Cu) are simultaneously concentrated at pH 4.3 with the combination of ammonium tetramethylenedithiocarbamate and dibenzylammonium dibenzyldithiocarbamate and are determined in the extract; Mn and Cr(III) are also determined after preconcentration at pH 6.9 with the same chelating agents. Lake waters are analyzed by this method. 相似文献
137.
Yuming Zhao Ningzhang Zhou Aaron D. Slepkov Sorin C. Ciulei Robert McDonald Frank A. Hegmann Rik R. Tykwinski 《Helvetica chimica acta》2007,90(5):909-927
A series of geminal diethynylethenes (g‐DEEs) with electron‐donating and/or electron‐accepting (D/A) groups were synthesized via a Pd‐catalyzed cross‐coupling sequence. The UV/VIS spectra for donor–acceptor (D–A) functionalized g‐DEEs 5, 8 , and 11 show distinctive absorption trends attributable to intramolecular charge‐transfer (ICT). The bond‐length‐alternation (BLA) index for the cross‐conjugated enediyne framework varies slightly with different terminal substituents as determined by density‐functional theory (DFT) calculations and single‐crystal X‐ray analysis. Ultrafast third‐order optical nonlinearities for the g‐DEEs were measured by the differential optical Kerr effect (DOKE) technique and show that terminal donor–acceptor substitution of g‐DEEs enhances molecular second hyperpolarizabilities (γ) in comparison to donor or acceptor g‐DEEs. A small increase in the two‐photon‐absorption cross‐section (σ(2)) is observed in the series 9 – 11 as a result of increased functionalization. The effects of donor/acceptor substitution on electron delocalization along the cross‐conjugated enediyne structure are evaluated on the basis of natural‐bond‐orbital (NBO) analysis. Solid‐state structures of the four derivatives 3b, 4b, 7 and 8 were characterized by single‐crystal X‐ray structural analysis and show an asymmetric unit cell for one derivative, D–A g‐DEE 8 . 相似文献
138.
N. I. Ionescu B. Albu I. Iosif M. Bozeanu G. Musca Gr. Pop 《Reaction Kinetics and Catalysis Letters》1985,28(2):437-441
The catalytic conversion of methanol to olefins over ZSM-5 zeolite modified by ion exchange with Mg exhibits an autocatalytic character. On this basis an overall kinetic model of the reaction was proposed which allowed the determination of rate constants and apparent activation energy.
ZSM-5, Mg, . , .相似文献
139.
Mihaela Monica Constantin Ctlina Gabriela Corbu Sorin Mocanu Elena Irina Popescu Marin Micutz Teodora Staicu Raluca omoghi Bogdan Tric Vlad Tudor Popa Aurica Precupas Iulia Matei Gabriela Ionita 《Molecules (Basel, Switzerland)》2022,27(1)
Riboflavin under UVA radiation generates reactive oxygen species (ROS) that can induce various changes in biological systems. Under controlled conditions, these processes can be used in some treatments for ocular or dermal diseases. For instance, corneal cross-linking (CXL) treatment of keratoconus involves UVA irradiation combined with riboflavin aiming to induce the formation of new collagen fibrils in cornea. To reduce the damaging effect of ROS formed in the presence of riboflavin and UVA, the CXL treatment is performed with the addition of polysaccharides (dextran). Hyaluronic acid is a polysaccharide that can be found in the aqueous layer of the tear film. In many cases, keratoconus patients also present dry eye syndrome that can be reduced by the application of topical solutions containing hyaluronic acid. This study presents physico-chemical evidence on the effect of riboflavin on collagen fibril formation revealed by the following methods: differential scanning microcalorimetry, rheology, and STEM images. The collagen used was extracted from calf skin that contains type I collagen similar to that found in the eye. Spin trapping experiments on collagen/hyaluronic acid/riboflavin solutions evidenced the formation of ROS species by electron paramagnetic resonance measurements. 相似文献
140.
G. M. Zinovjev S. V. Molodtsov A. N. Sissakian A. S. Sorin 《Physics of Particles and Nuclei Letters》2008,5(1):7-12
The paper is focused on calculating the finite temperature and quark/baryon chemical potential dependencies of the quark condensate and the π-and σ-meson masses in the subcritical region in the instanton model of the QCD vacuum. The impact of phononlike excitation of instanton liquid on the characteristics of the σ meson in such an environment is also examined. 相似文献