Numerical Algorithms - This article proposes modifications of the Parareal algorithm for its application to higher index differential algebraic equations (DAEs). It is based on the idea of applying... 相似文献
The aim of the current work was to determine thermo dynamical properties of 5(2-nitro phenyl)-furan-2-carbaldehyde, 5(3-nitro phenyl)-furan-2-carbaldehyde and 5(4-nitro phenyl)-furan-2-carbaldehyde.
Results
The temperature dependence of saturated vapor pressure of 5(2-nitro phenyl)-furan-2-carbaldehyde, 5(3-nitro phenyl)-furan-2-carbaldehyde and 5(4-nitro phenyl)-furan-2-carbaldehyde was determined by Knudsen’s effusion method. The results are presented by the Clapeyron–Clausius equation in linear form, and via this form, the standard enthalpies, entropies and Gibbs energies of sublimation and evaporation of compounds were calculated at 298.15 K. The standard molar formation enthalpies of compounds in crystalline state at 298.15 K were determined indirectly by the corresponding standard molar combustion enthalpy, obtained using bomb calorimetry combustion.
Conclusions
Determination of the thermodynamic properties for these compounds may contribute to solving practical problems pertaining optimization processes of their synthesis, purification and application and it will also provide a more thorough insight regarding the theoretical knowledge of their nature.
Vitamin B1‐selective electrodes with PVC membrane were developed that contain ion associates of vitamin B1 with an inorganic anion, BiI4?, and an organic anion, brilliant yellow, as electrode‐active substances. The linearity ranges of the electrode function are 1.0×10?5–1.0×10?2 and 1.0×10?4–1.0×10?2 M, the electrode function slopes are 33.0±1.0 and 33.1±1.1 mV decade?1, the detection limits are 5.5×10?6 and 8.3×10?5 M for BiI4? and brilliant yellow respectively. The working range of pH is 5–12. The efficiency of the use of electrodes for the vitamin B1 content control in multivitamin pharmaceutical preparations was shown by direct potentiometry and potentiometric titration methods. 相似文献
[structure: see text] Chiral calix[4]arene alpha-aminophosphonic acids were obtained through diastereoselective Pudovik-type addition of sodium ethyl phosphites to the chiral calixarene imines, removal of chiral auxiliary groups, and mild dealkylation of phosphonate fragments. The diacids obtained show inhibitory activity toward porcine kidney alkaline phosphatase that depends considerably on the absolute configuration of the alpha-carbon atoms. 相似文献
The partial and total densities of vibrational states of the 1/1 crystal approximant of the icosahedral i-AlCuFe quasicrystal are calculated using the method of pseudopotentials in the generalized gradient approximation (to describe the electronic states) and the frozen-phonon method (to determine the dynamic matrix). The results obtained agree well with experimental inelastic neutron scattering data, which indicates that the method of calculations is appropriate and could be used to calculate other crystal approximants. 相似文献
The cross talk of wavelength-multiplexed quasi-infinite (written in polychromatic light) holograms is evaluated. Under plausible conditions this cross talk is negligible. The typical information capacity limit of such holograms is evaluated as 10(12) bits for a 1-cm(3) volume. 相似文献
A novel diclofenac ion-selective electrode has been prepared and used in pharmaceutical analysis. The ion-associate of diclofenac with basic dye (crystal violet) was used as the membrane carrier. Among the four different solvent mediators tested, dibutylphthalate (DBP) exhibited proper behavior including the Nernstian slope of the calibration curve, fast response time and good reproducibility of the emf values. The electrode exhibits a Nernstian slope of 59 ± 1 mV decade?1 for diclofenac in the concentration range 5.0 × 10?5-5.0 × 10?2 M with the limit of detection of 2.5 × 10?5 M. The electrode displays good sensitivity with the respect to a number of common inorganic and organic species. It can be used in a pH range of 6–11. The membrane sensor was successfully applied to the determination of diclofenac in capsules and for its recovery from urine samples. 相似文献
New data on some cyclic dimethyl- and diethylindium-amides were obtained. X-ray structure of pyrrolidinodimethylindium was determined. The molecule is centrosymmetric with square-planar In2N2 base and distorted tetrahedral metal environment similar to that of known dialkylindium amides, the cyclic amido-ligands are present in an envelope conformation. A novel material- and energy-saving procedure for sorption ultra-purification of highly sensitive organometallic compounds in absolute non-polar media was developed. Advanced inorganic and inorgano-organic crystalline layered materials possessing enhanced affinity towards selected ions or molecules were applied for the sorption treatment. 相似文献
The thin organic films based on 4,4′-bis-[(Z)-1-(1,3-benzoxazol-2-yl-2-ethenyl)]biphenyl and its partly fluorinated derivatives
are studied. Absorption, luminescence, and excitation spectra, luminescence decay and film morphology were found to depend
sensitively on the changes in molecule structure, nature and temperature of the substrate, as well as the thermovacuum deposition
rate, being the origins of bad reproducibility of the optical properties of such films. Molecular aggregation with chromophore
dipoles arranged parallel to each other has been observed in absorption and luminescence spectra. The fluorescence characteristics
can be explained by the combination of radiation of aggregated and non-aggregated molecules. The main characteristics of the
molecules under study are calculated using DFT approach. The unusual behaviour of photodegradation in fluorinated film is
found. 相似文献