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21.
Magdalena Kurdziel Elżbieta Szczepaniec-Cięciak Barbara Dąbrowska Wojciech Nitek Katarzyna Paliś Edyta Ślusarska 《Journal of solution chemistry》2003,32(7):601-615
The solubilities of solid 2,3-dimethylbutane and cyclopentene in liquid argon at a temperature of 87.3 K and in liquid nitrogen at 77.4 K have been measured by the filtration method. The hydrocarbon contents in solutions were determined using gas chromatography. GC–MS was used to identify impurities in solutes. The experimental value of the mole fraction solubility of solid 2,3-dimethyl-butane in liquid argon at 87.3 K is (8.26 ± 1.60) × 10–6 and (2.77 ± 0.94) × 10–8 in liquid nitrogen at 77.4 K. The experimental value of the mole fraction solubility of solid cyclopentene in liquid argon at 87.3 K is (5.11 ± 0.44) × 10–6 and (4.60 ± 0.76) × 10–8 in liquid nitrogen at 77.4 K. The Preston–Prausnitz method was used for calculation of the solubilities of solid hydrocarbons in liquid argon in the temperature range 84.0–110.0 K and in liquid nitrogen from 64.0 to 90.0 K. The solvent–solute interaction parameters l
12 were also calculated. At 90.0 K liquid argon is a better solvent for investigated solid hydrocarbons than is liquid nitrogen. 相似文献
22.
Ionics - A new DP AdSV method was developed for the determination of the pesticide clothianidin (Clo) based on its nitro group reduction at the in situ renovated bismuth bulk annular band working... 相似文献
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Joanna Bryś Magdalena Wirkowska Agata Górska Ewa Ostrowska-Ligęza Andrzej Bryś Piotr Koczoń 《Journal of Thermal Analysis and Calorimetry》2013,112(1):481-487
The aim of this paper was to assess the oxidative stability of structured lipids synthesized by enzymatic interesterification of a blend of lard and rapeseed oil with concentrates of n ? 3 fatty acids. Differential scanning calorimetry was used to evaluate the oxidation induction time of interesterified fats as a parameter assessing resistance of tested fats to their thermal-oxidative decomposition. Moreover, the IR spectra registered in the classic spectral range (4000–400 cm?1) were used to differentiate the samples of interesterified fats. The results show that the interesterification process decreased the induction time. Increased content polar fraction in the interesterified fatty product can reduce its resistance to oxidation. FT-IR data of selected spectral ranges correlate with the value of induction time at a statistically significant level. This is a proof that chemical changes occurring during different treatments of the starting mixture can be monitored by FT-IR spectroscopy. Moreover, obtained correlations can be used for the evaluation of an induction value of an unknown oil sample. 相似文献
25.
Janusz Brzdęk Magdalena Piszczek 《Journal of Fixed Point Theory and Applications》2017,19(4):2441-2448
We prove a fixed point theorem for nonlinear operators, acting on some function spaces (of set-valued maps), which satisfy suitable inclusions. We also show some applications of it in the Ulam type stability. 相似文献
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Kęstutis Kubilius Dmitrij Melichov 《Methodology and Computing in Applied Probability》2016,18(3):785-804
In this paper exact confidence intervals for the Orey index of Gaussian processes are obtained using concentration inequalities for Gaussian quadratic forms and discrete observations of the underlying process. The obtained result is applied to Gaussian processes with the Orey index which not necessarily have stationary increments. 相似文献
29.
Małgorzata T. Kaczmarek Renata Jastrząb Wanda Radecka-Paryzek 《Journal of solution chemistry》2013,42(1):18-26
Formation of complexes between the lanthanide ions and N,N′-bis(salicylidene)-4-methyl-1,3-phenylenediamine ligand was studied in solution by pH potentiometry. The potentiometric titration was performed at 25.00 °C in 0.1 mol·dm?3 NaClO4 ionic strength and in DMSO:water (30:70 v:v) solvent mixture. N,N′-bis(salicylidene)-4-methyl-1,3-phenylenediamine ligand (H2L) occurs in three forms: fully or partially deprotonated and unionized. Computer analysis of potentiometric data indicated that in solution the lanthanide (Ln) complexes exist as LnL2, Ln(HL)2 and Ln(H2L)2 species. This observation appears to be in contrast to the solid-state behavior of these complexes prepared in a self-assembly process and structurally defined. Stability constants for La3+, Eu3+, Gd3+, Tb3+, Ho3+ and Lu3+ (Ln3+) complexes were determined. The order of stabilities of LnL2 species in terms of metal ions is La3+ > Eu3+ ≈ Gd3+ = Tb3+ < Ho3+ < Lu3+ with a prominent “gadolinium break”. 相似文献
30.
S. Khalameida V. Sydorchuk R. Leboda J. Skubiszewska-Zięba V. Zazhigalov 《Journal of Thermal Analysis and Calorimetry》2014,115(1):579-586
Interaction in the system of lithium carbonate–niobium pentoxide during mechanochemical treatment in air and water has been studied. Prepared samples have been investigated with the help of DTA–TG, XRD, FTIR, Raman, and UV–Vis spectroscopy, adsorption–desorption of nitrogen and TEM. Activation of reagents and direct mechanochemical synthesis are observed at 600–850 and 1,000 rpm, respectively. Lithium metaniobate samples prepared via milling possess high dispersity, defective structure, and improved photocatalytic activity, including under visible illumination. 相似文献