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61.
We introduce a twisted higher rank generalization of generalized Weyl algebras and study simple weight modules over such algebras. 相似文献
62.
We generalize the results of Kahn about a correspondence between Cohen-Macaulay modules and vector bundles to non-commutative surface singularities. As an application, we give examples of non-commutative surface singularities which are not Cohen-Macaulay finite, but are Cohen-Macaulay tame. 相似文献
63.
Volodymyr Nekrashevych 《Geometriae Dedicata》2007,124(1):153-190
We construct and study a family of 3-generated groups parametrized by infinite binary sequences w. We show that two groups of the family are isomorphic if and only if the sequences are cofinal and that two groups cannot
be distinguished by finite sets of relations. We show a connection of the family with 2-dimensional holomorphic dynamics.
相似文献
64.
Volodymyr D. Khavryuchenko Oleksiy V. Khavryuchenko Vladyslav V. Lisnyak 《固体与材料科学评论》2011,36(2):47-65
This article describes the genesis of amorphous silica under high-heat conditions from SiO2 molecules through protoparticles, primary particles, and aggregates to agglomerates using vibrational spectra and quantum chemical simulations data. The impact of small molecules (water, HCl, CO2) is also discussed. The article also explains the nature of the pyrogenic silica amorphism. 相似文献
65.
Nahirnyak VM Yoon SW Holland CK 《The Journal of the Acoustical Society of America》2006,119(6):3766-3772
The efficacy of ultrasound-assisted thrombolysis as an adjunct treatment of ischemic stroke is being widely investigated. To determine the role of ultrasound hyperthermia in the process of blood clot disruption, the acousto-mechanical and thermal properties of clotted blood were measured in vitro, namely, density, speed of sound, frequency-dependent attenuation, specific heat, and thermal conductivity. The amplitude coefficient of attenuation of the clots was determined for 120 kHz, 1.0 MHz, and 3.5 MHz ultrasound at room temperature (20 +/- 2 degrees C). The attenuation coefficient ranged from 0.10 to 0.30 Np/cm in porcine clots and from 0.09 to 0.23 Np/cm in human clots. The experimentally determined values of specific heat and thermal conductivity for porcine clotted blood are (3.2 +/- 0.5) x 10(3) J/kg x K and 0.55 +/- 0.13 W/m x K, respectively, and for human clotted blood are (3.5 +/- 0.8) x 10(3) J/kg x K and 0.59 +/- 0.11 W/m x K, respectively. Measurements of the acousto-mechanical and thermal properties of clotted blood can be helpful in theoretical modeling of ultrasound hyperthermia in ultrasound-assisted thrombolysis and other high-intensity focused ultrasound applications. 相似文献
66.
67.
We study the structure of the semigroup IO n of all order-preserving partial bijections on an n-element set. For this semigroup we describe maximal subsemigroups, maximal inverse subsemigroups, automorphisms and maximal nilpotent subsemigroups. We also calculate the maximal cardinality for the nilpotent subsemigroups in IO n which happens to be given by the n-th Catalan number. 相似文献
68.
V. A. Sadykov S. A. Beloshapkin E. A. Paukshtis G. M. Alikina I. Kochubei S. P. Degtyarev N. N. Bulgakov S. A. Veniaminov V. Netyaga R. V. Bunina A. N. Kharlanov E. V. Lunina V. V. Lunin V. A. Matyshak A. Ya. Rozovskii 《Reaction Kinetics and Catalysis Letters》1998,64(1):185-191
Transformation of surface nitrates under CH4 (CH4+O2) was found to ensure steady-state activity of Co-ZSM-5 in the selective catalytic reduction of nitrogen oxides by methane
(CH4-SCR). For Cu-ZSM-5, such species are mainly converted into NO. Relaxation of the coordination sphere due to oxygen and NO
adsorption, stability of C,N-containing intermediates and activation routes of hydrocarbons (methane, propane) were analyzed
as factors determining catalytic properties of Cu and Co cations. 相似文献
69.
70.
V. I. Kelarev S. G. Shvekhgeimer V. N. Koshelev G. A. Shvekhgeimer A. F. Lunin 《Chemistry of Heterocyclic Compounds》1984,20(7):721-723
The condensation of hydrochlorides of ethyl iminoesters of 4-hydroxy-3,5-di-tert-butylbenzoic and -(4-hydroxy-3,5-di-tert-butylphenyl) propionic acids with monoethanolamine, o-aminophenol, and o-phenylenediamine was studied. As a result, 2-oxazolines, benzoxazoles, and benzimidazoles containing sterically hindered phenol residues in the 2-position were synthesized.For Communication 34, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 889–892, July, 1984. 相似文献