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971.
Akbaş H Kartal C 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,65(1):95-99
The effect of electrolytes on the interaction between an anionic dye and a cationic surfactant was investigated spectrophotometrically in submicellar concentration range at certain temperature. The spectral change of the azo dye C.I. Reactive Orange 16 (RO16) exhibits a high sensitivity to the polarity of dye's environment. Dodecylpyridinium chloride (DPC) affects the electronic absorption spectra of dye solution that is dye-surfactant interaction results formation of complex and therefore a decrease in maximum absorption spectra (1.577 at 494 nm). The electrolyte cations cause an increase of the absorbance of DPC-RO16 ion-pair complex in the following order: Ca(2+)>Na(+)>NH(4)(+)>K(+)>Mg(2+), also for electrolyte anions Br(-)>Cl(-)>SO(4)(2-). Furthermore, this order can be changeable with increasing electrolyte concentration. The increase on absorbance value with increasing electrolyte concentration is explained as charge screening. The increase or decrease on absorption spectra of RO16-DPC solution depends on concentration range of the electrolyte added. As an increase on absorbance value with increasing electrolyte concentration is explained as charge screening, a decrease in this value for higher concentration of electrolyte is attributed as the charge of micelle shape. 相似文献
972.
We show that a complex manifold M in the boundary of a smooth bounded pseudoconvex domain Ω in is an obstruction to compactness of the -Neumann operator on Ω, provided that at some point of M, the Levi form of bΩ has the maximal possible rank n−1−dim(M) (i.e. the boundary is strictly pseudoconvex in the directions transverse to M). In particular, an analytic disc is an obstruction, provided that at some point of the disc, the Levi form has only one
zero eigenvalue (i.e. the eigenvalue zero has multiplicity one). We also show that a boundary point where the Levi form has
only one zero eigenvalue can be picked up by the plurisubharmonic hull of a set only via an analytic disc in the boundary.
Research supported in part by NSF grant number DMS-0100517. 相似文献
973.
In this paper, we describe, analyze and compare various multipliers. Particularly, we investigate the standard modular multiplication, the Montgomery multiplication, and the matrix–vector multiplication techniques. 相似文献
974.
There are three key ingredients in the study of the minimal genus problem for rational surfaces
: the generalized adjunction formula, the action of the orthogonal group of the Lorentz space and the geometric construction.
In this paper, we prove the uniqueness of the standard form (see Definition 1.1 and Theorem 1.1) of a 2-dimensional homology
class under the action of the subgroup of the Lorentz orthogonal group that is realized by the diffeomorphisms of
. Using the geometric construction, we determine the minimal genera of some classes (see Theorem 1.2). 相似文献
975.
Aluminium speciation in environmental samples: a review 总被引:2,自引:0,他引:2
Because of its toxic effects on living beings, Al may represent an environmental hazard, particularly under increased acidic
conditions. Growing environmental concern over the presence of increased Al concentrations in soil solutions and fresh waters
resulted in the development of numerous analytical techniques for the determination of Al species. Al has a very complex chemistry
that is significantly influenced by pH. Different Al species are present in environmental solutions, and many of them are
unstable. Contamination of samples and reagents by extraneous Al represents an additional problem in speciation of Al at trace
concentrations. Due to these reasons quantitative determination of particular chemical forms of Al is still a very difficult
task for analytical chemists. The most important analytical methodologies of the last decade and new trends for the speciation
of Al in environmental samples are comprehensively reviewed here. 相似文献
976.
The initial value problem solution of the nonlinear shallow water-wave equations is developed under initial waveforms with and without velocity. We present a solution method based on a hodograph-type transformation to reduce the nonlinear shallow water-wave equations into a second-order linear partial differential equation and we solve its initial value problem. The proposed solution method overcomes earlier limitation of small waveheights when the initial velocity is nonzero, and the definition of the initial conditions in the physical and transform spaces is consistent. Our solution not only allows for evaluation of differences in predictions when specifying an exact initial velocity based on nonlinear theory and its linear approximation, which has been controversial in geophysical practice, but also helps clarify the differences in runup observed during the 2004 and 2005 Sumatran tsunamigenic earthquakes. 相似文献
977.
Henry PG Adriany G Deelchand D Gruetter R Marjanska M Oz G Seaquist ER Shestov A Uğurbil K 《Magnetic resonance imaging》2006,24(4):527-539
In vivo 13C NMR spectroscopy has the unique capability to measure metabolic fluxes noninvasively in the brain. Quantitative measurements of metabolic fluxes require analysis of the 13C labeling time courses obtained experimentally with a metabolic model. The present work reviews the ingredients necessary for a dynamic metabolic modeling study, with particular emphasis on practical issues. 相似文献
978.
In [HOLá, Ľ.—HOLY, D.: Pointwise convergence of quasicontinuous mappings and Baire spaces, Rocky Mountain J. Math.] a complete answer is given, for a Baire space X, to the question of when the pointwise limit of a sequence of real-valued quasicontinuous functions defined on X is quasicontinuous. In [HOLá, Ľ.—HOLY, D.: Minimal USCO maps, densely continuous forms and upper semicontinuous functions, Rocky Mountain J. Math. 39 (2009), 545–562], a characterization of minimal USCO maps by quasicontinuous and subcontinuous selections is proved. Continuing
these results, we study closed and compact subsets of the space of quasicontinuous functions and minimal USCO maps equipped
with the topology of pointwise convergence. We also study conditions under which the closure of the graph of a set-valued
mapping which is the pointwise limit of a net of set-valued mappings, is a minimal USCO map. 相似文献
979.
Beloslav Riečan 《Mathematica Slovaca》2010,60(5):655-664
The classical Poincaré strong recurrence theorem states that for any probability space (Ω, ℒ, P), any P-measure preserving transformation T, and any A ∈ ℒ, almost all points of A return to A infinitely many times. In the present paper the Poincaré theorem is proved when the σ-algebra ℒ is substituted by an MV-algebra of a special type. Another approach is used in [RIEČAN, B.: Poincaré recurrence theorem in MV-algebras. In: Proc. IFSA-EUSFLAT 2009 (To appear)], where the weak variant of the theorem is proved, of course, for arbitrary MV-algebras.
Such generalizations were already done in the literature, e.g. for quantum logic, see [DVUREČENSKIJ, A.: On some properties of transformations of a logic, Math. Slovaca 26 (1976), 131–137. 相似文献
980.