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41.
A convenient approach to the synthesis of 2-amino-4,6-diphenylnicotinonitriles via four-component reaction of aromatic aldehydes, acetophenone derivatives, malononitrile and ammonium acetate is described. The reactions were done in water as solvent using cellulose sulfuric acid as catalyst. This simple protocol offer advantages such as shorter reaction times, simple work-up procedure, excellent yields and catalyst recovery.  相似文献   
42.
Results obtained from an analysis of the energy spectrum of cosmic rays with energies in the region of E0 ≥ 1017 eV over the period of continuous observations from 1974 to 2017 are presented. A refined expression for estimating the primary-particle energy is used for individual events. This expression is derived from calculations aimed at determining the responses of the ground-based and underground scintillation detectors of the Yakutsk array for studying extensive air showers (EAS) and performed within theQGSJET-01-d, QGSJET-II-04, SIBYLL-2.1, and EPOS-LHCmodels by employing the CORSIKA code package. The new estimate of E0 is substantially lower than its counterpart used earlier.  相似文献   
43.
Russian Journal of Applied Chemistry - Owing to high stability, metal oxide-based ceramic thin films are of great interest for photocatalytic oxidation of water. Therefore, the current research is...  相似文献   
44.
45.
A reversed-phase hydrolytically stable packing material prepared by chemisorption of a trifluorostyrene-containing copolymer on to the surface of porous silica was tested by high-performance liquid chromatography of various aromatic compounds. It was found that the polytrifluorostyrene (PTFS) phase has an intermediate adsorption activity between those of polytetrafluoroethylene and polystyrene phases. A high selectivity of PTFS-coated silica in the separation of haloaryl compounds was observed. Wide-pore silica coated with PTFS was found to give an efficient resolution of peptides and proteins.  相似文献   
46.
The electrode potentials of some quinone derivatives in aqueous solution have been calculated. The calculations are carried out at the Hartree–Fock and B3LYP levels with the inclusion of entropic and thermochemical corrections to yield free energies of redox reactions. The Polarisable Continuum Model (PCM) is used to describe the solvent. The average error of calculation of electrode potentials is less than 0.03 V and is decreased compared to the average error of methods presented previously. The role of relaxation energies and frequency calculations in improving the results has been investigated.  相似文献   
47.
We report the design and synthesis of a liquid crystalline material exhibiting highly ordered smectic phases and high charge carrier-mobility; by a process known as "paramorphosis" highly ordered smectic phases can be transferred to the amorphous crystalline state on crystallisation without the formation of significant crystal grain boundaries and deep traps.  相似文献   
48.
Ijaz  M.  Nadeem  S.  Ayub  M.  Mansoor  S. 《Journal of Thermal Analysis and Calorimetry》2021,143(3):2053-2067
Journal of Thermal Analysis and Calorimetry - The present paper explores the features of thermal radiation on ferromagnetic Jeffrey fluid flow within the frame of gyrotactic microorganisms and...  相似文献   
49.
Reactive dyeings were carried out by exhaust method on 100% cotton knits. A trichromatic combination was chosen with only change in blue component. Colorimetric data were produced under controlled dyeing conditions by comparing the color difference between the target shade and resulting shades. Giving a change in liquor ratio and nature of salt the colorimetric data were regenerated again produced the shades. The data will be helpful to predict the low-sensitivity reactive dye recipe, which lead to the concept of right-first-time dyeing. The aim of this research is to help a dyer to select the right recipe. A set of the dye recipes was applied by dyeing with reactive dyes on cotton. Sodium chloride shows best results in terms of dye sensitivity as compared to Glauber's salt at low liquor ratio that is 1:10. Blue BRF in combination with yellow and red shows best result as compared to navy blue BF.  相似文献   
50.
Journal of Thermal Analysis and Calorimetry - This paper deals with an advanced colorimetric method used to determine the catalase mimetic activity of V2O5 nanoparticles by measuring the decrease...  相似文献   
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