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71.
72.
Smaranda Iliescu Gheorghe Ilia Ludovic Kurunczi Gheorghe Dehelean Lavinia Macarie 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract Polyphosphonates were synthesized by interfacial alkaline polycondensation of bispheml A (BA) with phenyldichlorophosphonate (PPD) and cyclohexyl-dichlorophosphonate (CPD) in liquid-liquid[1] (1–1) and Iiquid-vapoR[2] (I-v) systems. 相似文献
73.
Andreea Irina Barzic Dan Gheorghe Dimitriu Dana Ortansa Dorohoi 《International Journal of Polymer Analysis and Characterization》2015,20(6):565-571
The proposed method of channeled spectrum employs the recorded channeled spectrum of an optical active polymer solution placed between two crossed polarizers. The approach allows the evaluation of the optical rotatory dispersion of poly(propylene oxide) in benzene. The specific rotation, circular birefringence, and dispersion parameter depend on the wavelengths of the maxima and minima from the channeled spectrum. 相似文献
74.
Vadim A. Babkin Gheorghe Cata-Danil Viacheslav M. Golovatyuk Aleksandr G. Molokanov Mihaela M. Paraipan Gennady N. Timoshenko 《Central European Journal of Physics》2010,8(4):683-688
A ridge carbon beam filter for Spreading Out the Bragg Peak (SOBP) up to 20 mm in the targeted area has been designed and experimentally tested. The instrument was constructed of Plexiglas with a density of 1.165 g/cm3 and has a “teeth” structure with a period of 2.5 mm. The design is based on a simple analytical model and detailed GEANT4 Monte Carlo simulations. In-beam test measurements were performed with a 500-MeV/u 12C beam at the Nuclotron facility of the Joint Institute for Nuclear Research (JINR) in Dubna. The filter can be used as a static device positioned in front of patients undergoing carbon therapy. 相似文献
75.
In this paper we are concerned with the study of a class of quasilinear elliptic differential inclusions involving the anisotropic $\overrightarrow {p}(\cdot)$ -Laplace operator, on a bounded open subset of ${\mathbb R}^n$ which has a smooth boundary. The abstract framework required to study this kind of differential inclusions lies at the interface of three important branches in analysis: nonsmooth analysis, the variable exponent Lebesgue–Sobolev spaces theory and the anisotropic Sobolev spaces theory. Using the concept of nonsmooth critical point we are able to prove that our problem admits at least two non-trivial weak solutions. 相似文献
76.
Dana Gheorghe 《Journal of Mathematical Analysis and Applications》2009,354(1):273-285
Using some techniques of perturbation theory for quotient morphisms between Banach spaces we obtain necessary and sufficient conditions for the stability of the topological index of a q-open quotient morphism under small (with respect to the gap topology) perturbations with quotient morphisms. As an application we obtain necessary and sufficient conditions for the stability of the topological index of an open linear relation with closed multivalued part between normed spaces under small perturbations with linear relations. 相似文献
77.
Let Ω be a bounded domain in with C2-smooth boundary, , of co-dimension 1, and let be a Schr?dinger operator on Ω with potential . We seek the weakest conditions we can find on the rate of growth of the potential V close to the boundary which guarantee essential self-adjointness of H on . As a special case of an abstract condition, we add optimal logarithmic type corrections to the known condition where . More precisely, we show that if, as x approaches ,
where the brackets contain an arbitrary finite number of logarithmic terms, then H is essentially self-adjoint on . The constant 1 in front of each logarithmic term is optimal. The proof is based on a refined Agmon exponential estimate
combined with a well-known multidimensional Hardy inequality.
Submitted: November 18, 2008.; Accepted: January 19, 2009.
We wish to thank F. Gesztesy, A. Laptev, M. Loss and B. Simon for useful comments and suggestions. I.N.’s research was partly
supported by the NSF grant DMS 0701026. 相似文献
78.
This paper is the second in a series revisiting the (effect of) Faraday rotation. We formulate and prove the thermodynamic limit for the transverse electric conductivity of Bloch electrons, as well as for the Verdet constant. The main mathematical tool is a regularized magnetic and geometric perturbation theory combined with elliptic regularity and Agmon-Combes-Thomas uniform exponential decay estimates. 相似文献
79.
Approximations to mild solutions of stochastic semilinear equations with non-Lipschitz coefficients 总被引:3,自引:0,他引:3
In the present paper, using a Picard Type method of approximation, we investigate the global existence of mild solutions for a class of Ito Type stochastic differential equations whose coefficients satisfy conditions more general than the Lipschitz and linear growth ones. 相似文献
80.
It is proved that if S, T are two elliptic Dirichlet operators on an ordered Hilbert space such that the excessive (resp. coexcessive) elements with respect to S and T are the same then there exists > 0 with T = S. Particularly if , are two elliptic Dirichlet forms on L2 ( ) having the same domain of definition and the same -excessive (resp. -coexcessive) elements for any > 0 then = . 相似文献