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21.
Certain condition on the second fundamental form of CR submanifolds of maximal CR dimension of complex Euclidean space 总被引:1,自引:0,他引:1
We treat m-dimensional real submanifolds M of complex space forms ̿M when the maximal holomorphic tangent subspace is (m−1)-dimensional. On these manifolds there exists an almost contact structure F which is naturally induced from the ambient space and in this paper we study the condition h(FX,Y)−h(X,FY) = g(FX,Y)η, η∊ T⊥(M), on the structure F and on the second fundamental form h of these submanifolds. Especially when the ambient space ̿M is a complex Euclidean space, we obtain a complete classification of submanifolds M which satisfy these conditions.Mathematics Subject Classifications (2000): 53C15, 53C40, 53B20. 相似文献
22.
Mirjana STOJANOVIC 《数学学报(英文版)》2006,22(2):393-406
We consider nonlinear parabolic equations with nonlinear non-Lipschitz's term and singular initial data like Dirac measure, its derivatives and powers. We prove existence-uniqueness theorems in Colombeau vector space yC^1,W^2,2([0,T),R^n),n ≤ 3. Due to high singularity in a case of parabolic equation with nonlinear conservative term we employ the regularized derivative for the conservative term, in order to obtain the global existence-uniqueness result in Colombeau vector space yC^1,L^2([0,T),R^n),n≤ 3. 相似文献
23.
Vrankić Ilko Herceg Tomislav Pejić Bach Mirjana 《Central European Journal of Operations Research》2021,29(3):1001-1019
Central European Journal of Operations Research - In this paper, we analyse the company behaviour in duopoly taking into account the most common strategies, including dominant, reactive,... 相似文献
24.
A compatible statistical interpretation of a wave packet is proposed. De Broglian probabilities which unite wave and particle features of quantons are evaluated for free wave packets and Jor a superposition of wave packets. The obtained expressions provide a very plausible and physically appealing explanation of coherence in apparently incoherent beams and of the characteristic modulation of the momentum distribution, found recently in neutron interferometry combined with spectral filtering. Certain conclusions about dualism and objectivity in quantum domain are also derived. 相似文献
25.
Mirjana Stojanović 《BIT Numerical Mathematics》1990,30(1):171-176
It is proved that a spline difference scheme for a singularly perturbed self-adjoint problem, derived by using exponential cubic splines at mid-points, has second order uniform convergence in a small parameter . Numerical experiments are presented to confirm the theoretical predictions. 相似文献
26.
The new techniques and ideas in quantum interferometry with neutrons, photons, atoms, electrons, and Bose condensates that fluorished in the last two decades have influenced in a decisive way the thinking and the research in the foundations and interpretation of quantum mechanics. The controversies existing among different schools on the reality of matter waves of quantum theory, the postulates of quantum measurement theory, and the (in)completeness of quantum mechanics have to be approached now in a new way. Our argumentation follows the spirit of the Paris school. 相似文献
27.
Jovana Francuz Bojana Srećo Mirjana Popsavin Goran Benedeković Vladimir Divjaković Vesna Kojić Gordana Bogdanović Agneš Kapor Velimir Popsavin 《Tetrahedron letters》2012,53(14):1819-1822
Treatment of 7-O-benzoyl-5-O-benzyl derivatives of (+)-goniofufurone or 7-epi-(+)-goniofufurone with titanium(IV) chloride or titanium(IV) bromide gave 7-chloro and 7-bromo-7-deoxy-goniofufurone mimics as the main reaction products along with minor amounts of the corresponding C-7 epimers. An unexpected cyclized product, benzoxepane 8 was isolated in some cases. 相似文献
28.
Pance Naumov Mirjana Ristova Michael G. B. Drew Seik Weng Ng 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):e372-e373
In the title compound, [Ni(C2H3O)2(C3H4N2)4], the Ni atom is coordinated centrosymmetrically by four N and two O atoms in an octahedral coordination [Ni—N = 1.986 (3) and 2.054 (3) Å; Ni—O = 2.697 (3) Å]. The O atoms of the acetate anions form hydrogen bonds to adjacent imidazole moieties, with the free O atom forming a somewhat shorter bond [N?O = 2.679 (3) and 2.870 (4) Å]. The hydrogen bonds give rise to a two‐dimensional layer structure. 相似文献
29.
Gerber B Mathys P Moser M Bressoud D Braun-Fahrländer C 《Photochemistry and photobiology》2002,76(6):664-668
It is well known that UV radiation contributes to the development of skin cancer. Exposure to solar radiation is predominantly responsible for the high incidence rate of skin cancer, but there are also indications that sunbeds are involved. The aim of the present investigation was to determine the UV emission spectra of sunbeds. It included the most common sunbed models, which cover more than 50% of the Swiss market. The UV emission spectra of sunbeds have special characteristics and are different from the sun spectrum, which can be seen in high-resolution spectral measurements. Sunbed emission spectra are similar to the sun spectrum in the UVB (280-320 nm) range but reach values 10 to 15 times higher in the UVA (320-400 nm) range. An average erythema-effective irradiance of 0.33 W/m2 was determined for sunbeds. This corresponds to a UV index of 13, which is significantly higher than the UV index of 8.5 of the high summer sun at noon at intermediate latitudes. The measurements were spread over the whole effective area of the sunbeds, and an inhomogeneous distribution of the irradiances with variations of up to 30% from the average value was found. 相似文献
30.
Stajic M Persky L Hadar Y Friesem D Duletic-Lausevic S Wasser SP Nevo E 《Applied biochemistry and biotechnology》2006,128(1):87-96
Copper (Cu2+) and manganese (Mn2+) ions influenced laccase (Lac) and peroxidase production in Pleurotus eryngii, Pleurotus ostreatus, and Pleurotus pulmonarius. In P. eryngii, the optimum Cu2+ concentration for Lac production was 1 mM and for peroxidases 10mM, and Mn2+ concentration of 5mM led to peaks of Lac and peroxidase activity. In P. ostreatus HAI 493, the highest level of Lac activity was at Cu2+ concentrations of 1 and 10 mM and Mn2+ concentration of 1mM, respectively. The absence of Cu2+ and Mn2+ caused the highest levels of peroxidase production. In P. ostreatus HAI 494, the highest level of Lac activity was at a Cu2+ concentration of 5 mM and at Mn2+ concentration of 1 mM, respectively. High levels of peroxidase activity were found in the medium without and with 1mM Cu2+, and at 1 and 5 mM Mn2+, respectively. In P. pulmonarius, the highest Lac activity was found in the presence of 5 mM Cu2+ and 5 mM Mn2+, respectively. The absence of Cu2+ and Mn2+ as well as their presence at a concentration of 1 mM led to the peaks of peroxidase activities. 相似文献