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991.
Ordered mesoporous carbon (OMC) was used as an adsorbent for the removal of pertechnetate (TcO4 ?) anion. The maximum uptake (93 %) of TcO4 ? was obtained after 60 min of contact. The adsorption of TcO4 ? is almost pH-independent in very wide pH region (from 4.0 to 10.0). Maximum K d of 6.6 × 103 cmg?1 was found at pH 2.0. TcO4 ? interacts with carboxylic functional groups present at the surface of the OMC by displacing the OH? ions with TcO4 ? via ion exchange mechanism.  相似文献   
992.
993.
The paper considers a statistical concept of causality in continuous time in the filtered probability spaces which is based on the Granger’s definition of causality. The given causality concept is then applied to the solution of the martingale problem (associated with the stochastic differential equation driven with semimartingales). More precisely, we show that the given causality concept is closely connected to the concept of extremality of measures for the solutions of the martingale problem, for the stopped martingale problem and for the local martingale problem. We also show the equivalence between some models of causality and local uniqueness (for the solutions of the martingale problem).  相似文献   
994.
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   
995.
Abstract

Medicinal plants play an important role in aquaculture as feed additives. This study aimed to investigate effects of alcoholic extract of acorn on growth performance, body composition, digestive enzymes activity and blood biochemical parameters of rainbow trout (O. mykiss) as a commercially important fish. Five dietary treatments were supplemented: 100, 200, 400 and 600?mg.kg?1 of the extract. Fishes were fed twice per day for 8?weeks, and results showed that acorn extract positively affected all investigated parameters in rainbow trout fishes. Digestive enzymes activity and growth performance were increased, while activity of liver enzymes and cortisol were lowed in comparison to control individuals. Body composition of treated animals was also enhanced. Comparison between treated groups together with integrative biomarker response (IBR) values indicated greatest effects in animals fed with 400 and 600?mg.kg?1 of the extract. Positive effects of the acorn represent promising start point for further studies.  相似文献   
996.
997.
Ambient pressure chemical hydrogenation using p-toluene sulfonyl hydrazide (TSH) via thermal diimide formation (N2H2) permitted reduction of double bonds of poly(myrcene) (poly[Myr]) and poly(farnesene) (poly[Far]). Both pendent and backbone double bonds in poly(Myr) (Mn = 56 kg/mol) and poly(Far) (Mn = 62 kg/mol) synthesized by conventional free radical polymerization were hydrogenated to almost completion. Furthermore, TSH semi-batch addition efficiently hydrogenated double bonds, while avoiding undesired autohydrogenation of diimides that occurred in batch mode. Thermal stability improved for hydrogenated poly(Myr) and poly(Far), where temperature at 10% weight loss (T10%) increased from 188 to 404°C for poly(Myr) and from 310 to 379°C for poly(Far). Tgs of poly(Myr) and poly(Far) also increased by about 10–25°C, indicating increased stiffness after hydrogenation. Finally, viscosities of poly(Myr) and poly(Far) were also increased after hydrogenation, and a greater increase was observed for poly(Myr) (by two orders of magnitude from 102 to 104 Pa s) due to its Mn being much higher than its entanglement molecular weight. Poly(Far) viscosity only increased by 1.5 times after hydrogenation (~104 Pa s), comparable to the poly(Myr) after hydrogenation, suggesting unsaturated poly(Far) was more entangled than unsaturated poly(Myr) because of its longer side chains.  相似文献   
998.
999.
Sole lineshape estimation of non-parametrically computed higher-order derivatives of spectral envelopes in different modes (complex, real, imaginary, magnitude) is investigated. The processed time signals are sums of complex attenuated exponentials (harmonics). The peak parameters of the derivative spectra are directly connected to those of the customary (non-derivative) absorption lineshapes. Crucially, this permits the reconstruction of the latter from the former parameters (the latter are sought since they are unknown, whereas the former are extractable from the derivative envelopes). The cross-checking relationships of the lineshapes for the magnitude modes with the real and imaginary parts of the complex-valued envelopes (total shape spectra) are established. The explicit procedure and the necessary analytical expressions are presented for reconstruction of the exact locations, widths and heights of all the retrieved physical resonances (spectral peaks). These facets are illuminated in the derivative fast Padé transform (dFPT) using its non-parametric version, i.e. without solving the quantification problem (no polynomial rooting, no tackling of eigen-value problems, etc.). Two kinds of illustrations for derivative spectra are reported. One deals with the general Breit-Wigner resonance formula and its first three derivatives. The other is concerned with the dFPT in clinical diagnostics of relevance to breast cancer detection by magnetic resonance spectroscopy. A systematic parallel between these two examples is drawn to highlight, in a stepwise manner, the role of paramount importance played by derivative lineshapes, especially for disentangling overlapping resonances that invariably plague all quantitative analyses of spectra.  相似文献   
1000.
Electron impact excitation rate coefficients for singlet and triplet electronic states of the carbon monoxide molecule have been calculated under non-equilibrium conditions in the presence of radio-frequency electric field. A Monte Carlo simulation of electron transport has been performed in order to determine non-equilibrium electron energy distribution functions within one period of applied electric field. By using these distribution functions and corresponding cross sections, the excitation rate coefficients have been calculated for all electronic states of CO in the frequency range from 13.56 up to 500 MHz, at reduced root mean square electric field values ranging from 200 to 700 Td. We expect these rates to be valuable for modeling radio-frequency CO plasmas since excited neutrals exhibit greater chemical reactivity than neutrals in ground electronic state, hence altering many properties of plasma.  相似文献   
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