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91.
Journal of Radioanalytical and Nuclear Chemistry - In the present study, the actual levels and temporal changes of 34 major and trace elements were examined in 44 moss samples Hypnum cuppressiforme...  相似文献   
92.
The purpose of this paper is to suggest and analyze a number of iterative algorithms for solving the generalized set-valued variational inequalities in the sense of Noor in Hilbert spaces. Moreover, we show some relationships between the generalized set-valued variational inequality problem in the sense of Noor and the generalized set-valued Wiener-Hopf equations involving continuous operator. Consequently, by using the equivalence, we also establish some methods for finding the solutions of generalized set-valued Wiener-Hopf equations involving continuous operator. Our results can be viewed as a refinement and improvement of the previously known results for variational inequality theory.  相似文献   
93.
94.
A spin-1 Blume–Capel model with dilute and random crystal fields is examined for honeycomb and square lattices by introducing an effective-field approximation that takes into account the correlations between different spins that emerge when expanding the identities. For dilute crystal fields, we have given a detailed exploration of the global phase diagrams of the system in kBTc/J−D/JkBTc/JD/J plane with the second and first order transitions, as well as tricritical points. We have also investigated the effect of the random crystal field distribution characterized by two crystal field parameters D/JD/J and △/J/J on the phase diagrams of the system. The system exhibits clear distinctions in a qualitative manner with coordination number qq for random crystal fields with △/J,D/J≠0/J,D/J0. We have also found that, under certain conditions, the system may exhibit a number of interesting and unusual phenomena, such as reentrant behavior of first and second order, as well as a double reentrance with three successive phase transitions.  相似文献   
95.
The decay of the hysteresis loop area of the system, which is obeying a site diluted kinetic Ising model, is considered by the disorder parameter using the effective field theory analysis. The exhibition focuses on the understanding of external field frequency, amplitude and the site concentration dependency of the hysteresis loop area for several powerful treatments. Important characteristics of the hysteretic response, such as frequency dispersion, effect of domain nucleation phenomenon on the dynamic process, etc., has been introduced together with well known other characteristics. An attempt has been made to explain the relations between the competing time scales (intrinsic microscopic relaxation time of the system and the time period of the external oscillatory field) and the shape of the response. As a result of the detailed investigations, existence of essentially three, particularly four types of dispersion curves have been propounded.  相似文献   
96.
In this paper, we consider the system of nonlinear quasi-mixed equilibrium problems. The existence theorems of solutions of such problems are provided by considering the limit point of an iterative algorithm. This means, we not only give the conditions for the existence theorems of the presented problems but also provide the algorithm to find such solutions. Moreover, the stability of such an algorithm is also discussed. The results presented in this paper are more general, and may be viewed as an extension, refinement and improvement of the previously known results in the literature.  相似文献   
97.
This study deals with the removal of Fe(III) and Cu(II) from dilute aqueous solutions using a polymer-enhanced ultrafiltration process. The ultrafiltration studies were carried out in batch stirred cell and the applied pressure was controlled by nitrogen gas. Properties of the composite membranes and its application in metal removal from aqueous solutions were studied. A composite poly(vinyl alcohol)-alginic acid/cellulose membranes were prepared by coating poly(vinyl alcohol)-alginic acid mixture solutions on the filter paper. Poly(vinyl alcohol) and alginic acid were also used as complexing agents to enhance the retention of metal ions. In the filtration of Fe(III) and Cu(II) solutions, the effects of membrane contents, pressure and pH on the retention and the flux were studied. The maximum retention of metals was found as 99% for Fe(III) solution at pressure of 45 psi, pH of 3 in the presence of poly(vinyl alcohol) as complexing agent by using 0.50 (w/v)% [(75 Poly(vinyl alcohol)/25 Alginic acid) (w/w)]/cellulose composite membranes.  相似文献   
98.
We prove several results concerning the existence of common invariant finite sets of vertices or of common invariant finite connected subgraphs for some families of endomorphisms of graphs whose ends are all dominated.  相似文献   
99.
We prove several fixed subgraph properties. In particular it is shown that if is a commuting family of contractions of a connected graph G without infinite path and infinite interval, then there exists a nonempty finite subgraph F which is invariant under any element of . In particular this subgraph F is a simplex if G is moreover a strongly dismantlable graph or a ball-Helly graph without infinite block, or if it is chordal. This implies that for any commuting family of contractions of a tree without infinite path, there is a common fixed vertex or a common fixed edge.  相似文献   
100.
The main aim of this work is to use the resolvent operator technique to find the common solutions for a generalized system of relaxed cocoercive mixed variational inequality problems and fixed point problems for Lipschitz mappings in Hilbert spaces. An example of applying the main result is also given. The results obtained in this work may be viewed as an extension, refinement and improvement of the previously known results.  相似文献   
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