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The preparative conditions were optimized to get chalcogens layers on the polymer — polyamide PA surface by sorption at room temperature using sodium telluropentathionate, Na2TeS4O6. Further interaction of chalcogenized dielectric with copper’s (I/II) salt solution leads to the formation of mixed CuxSy-CuxTey layers. Optical, electrical and surface characteristics of the layers are highly controlled by the deposition parameters. The stoichiometry of these layers was established by UV-Visible and AA spectrometry. Optical absorption (transmittance) experiments show the samples are of high optical quality. The band gaps of thin films were obtained from their optical absorption spectra, which were found in the range of 1.44–2.97 eV. XRD was used in combination with AFM to characterize chalcogenides layers’ structural features. XRD analysis confirmed the formation of mixed copper chalcogenides’ layers in the surface of PA with binary phases such as Cu2Te, Cu3.18Te2, copper telluride, Cu2.72Te2, vulcanite, CuTe, anilite, Cu7S4 and copper sulfide, Cu1.8S. The crystallite sizes of thin films calculated by the Scherer formula were found to be in the range of 3.07–13.53 nm for CuxSy crystallites and 4.06–20.79 nm for CuxTey crystallites. At room temperature an electrical resistance of CuxSy-CuxTey layers varies from 3.0×103 kΩ□?1 to 1.0 kΩ□?1. 相似文献
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Alena Vollmannova Janettte Musilova Tomas Toth Julius Arvay Judita Bystricka Michal Medvecky 《International journal of environmental analytical chemistry》2013,93(14-15):1445-1451
The aim of this study was to determine the content of Cu, Zn, Cd and Pb and the total polyphenol (TP) content as well as the total antioxidant capacity (TAC) in wild cranberries and blueberries collected from different localities of the Slovakia and to compare them with properties of six cranberry and six highbush blueberry cultivars obtained from the research centre. Compared with cultivated cranberries (Cu, Zn, Cd and Pb content: 0.642, 1.496, 0.015 and 0.050 mg/kg FM) in wild fruits, higher Cu (by 37%) and lower Zn, Cd and Pb (by 8%, 7% and 44% respectively) were determined using atomic absorption spectrometry method. In wild blueberries, higher Cu, Zn and Pb (by 16%, 209% and 80% respectively) and similar Cd contents were determined compared with cultivated fruits (Cu, Zn, Cd and Pb content: 0.483, 0.541, 0.003 and 0.055 mg/kg FM). The TP contents estimated by spectrophotometry using Folin–Ciocalteau reagent were in intervals 1405–3161 (cranberries) and 1300–3077 (blueberries) expressed as mg GAE/kg FM. While the average TP content determined in wild cranberries was by 31% lower than that in cultivated cranberries, in wild blueberries it was by 97% higher compared with highbush blueberry cultivars. The values of TAC determined by spectrophotometry method using 2,2-diphenyl-1-picrylhydrazyl were in range 20.67–22.22 (cranberries) and 14.03–24.79 (blueberries) expressed as mmol TE/kg FM. In wild cranberries and blueberries, the lower average TAC values compared with cultivated berries were determined (by 1% and 28%, respectively). 相似文献
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Judita Cofman 《Elemente der Mathematik》1997,52(3):108-117
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The notion of a relatively uniform convergence (ru-convergence) has been used first in vector lattices and then in Archimedean
lattice ordered groups.
Let G be an Archimedean lattice ordered group. In the present paper, a relative uniform completion (ru-completion) of G is dealt with. It is known that exists and it is uniquely determined up to isomorphisms over G. The ru-completion of a finite direct product and of a completely subdirect product are established. We examine also whether
certain properties of G remain valid in . Finally, we are interested in the existence of a greatest convex l-subgroup of G, which is complete with respect to ru-convergence.
This work was supported by Science and Technology Assistance Agency under the contract No. APVT-20-004104. Supported by Grant
VEGA 1/3003/06. 相似文献
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Let ${I\subset\mathbb{R}}$ be a nonvoid open interval and let L : I 2→ I be a fixed strict mean. A function M : I 2→ I is said to be an L-conjugate mean on I if there exist ${p,q\in\,]0,1]}$ and ${\varphi\in CM(I)}$ such that $$M(x,y):=\varphi^{-1}(p\varphi(x)+q\varphi(y)+(1-p-q) \varphi(L(x,y)))=:L_\varphi^{(p,q)}(x,y),$$ for all ${x,y\in I}$ . Here L(x, y) : = A χ(x, y) ${(x,y\in I)}$ is a fixed quasi-arithmetic mean with the fixed generating function ${\chi\in CM(I)}$ . We examine the following question: which L-conjugate means are weighted quasi-arithmetic means with weight ${r\in\, ]0,1[}$ at the same time? This question is a functional equation problem: Characterize the functions ${\varphi,\psi\in CM(I)}$ and the parameters ${p,q\in\,]0,1]}$ , ${r\in\,]0,1[}$ for which the equation $$L_\varphi^{(p,q)}(x,y)=L_\psi^{(r,1-r)}(x,y)$$ holds for all ${x,y\in I}$ . 相似文献
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Let X be a nonempty set containing at least two elements and let \({\circ :X^2\to X}\) be a symmetric binary operation. Furthermore, let A, B, C be real parameters and let \({f,g:X\to\mathbb{R}_+}\) be unknown functions. We investigate the functional equation
相似文献
$f(x\circ y)[Ag(y)-Bg(x)]=(A+C)f(x)g(y)-(B+C)f(y)g(x)\quad {\rm for\,\,all}\,x,y \in X.$
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