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91.
Komornikov V. A. Timakov I. S. Zajnullin O. B. Grebenev V. V. Makarova I. P. Selezneva E. V. Ksenofontov D. A. 《Crystallography Reports》2019,64(6):984-990
Crystallography Reports - The phase equilibria in the CsHSO4–CsH2PO4–NH4H2PO4–H2O four-component aqueous salt system have been studied. The crystallization ranges and solubilities... 相似文献
92.
Journal of Applied and Industrial Mathematics - The weighted vertex coloring problem for a given weighted graph is to minimize the number of colors so that for each vertex the number of the colors... 相似文献
93.
Doklady Physics - The frequency and concentration dependences of the effective complex permittivity of a composite consisting of silver nanoparticles in a polystyrene dielectric matrix have been... 相似文献
94.
A new asymmetric Salamo‐based ligand H2L was synthesized using 3‐tert‐butyl‐salicylaldehyde and 6‐methoxy‐2‐[O‐(1‐ethyloxyamide)]‐oxime‐1‐phenol. By adjusting the ratio of the ligand H2L and Cu (II), Co (II), and Ni (II) ions, mononuclear, dinuclear, and trinuclear transition metal (II) complexes, [Cu(L)], [{Co(L)}2], and [{Ni(L)(CH3COO)(CH3CH2OH)}2Ni] with the ligand H2L possessing completely different coordination modes were obtained, respectively. The optical spectra of ligand H2L and its Cu (II), Co (II) and Ni (II) complexes were investigated. The Cu (II) complex is a mononuclear structure, and the Cu (II) atom is tetracoordinated to form a planar quadrilateral structure. The Co (II) complex is dinuclear, and the two Co (II) atoms are pentacoordinated and have coordination geometries of distorted triangular bipyramid. The Ni (II) complex is a trinuclear structure, and the terminal and central Ni (II) atoms are all hexacoordinated, forming distorted octahedral geometries. Furthermore, optical properties including UV–Vis, IR, and fluorescence of the Cu (II), Co (II), and Ni (II) complexes were investigated. Finally, the antibacterial activities of the Cu (II), Co (II), and Ni (II) complexes were explored. According to the experimental results, the inhibitory effect was found to be enhanced with increasing concentrations of the Cu (II), Co (II), and Ni (II) complexes. 相似文献
95.
Dustin T. Savage Nicolas J. Briot J. Zach Hilt Thomas D. Dziubla 《Journal of polymer science. Part A, Polymer chemistry》2021,59(4):289-299
Per- and polyfluoroalkyl substances (PFAS) have rapidly accumulated in the environment due to their widespread use prior to commercial discussion in the early 21st century, and their slow degradation has magnified concerns of their potential toxicity. Monitoring their distribution is, therefore, necessary to evaluate and control their impact on the health of exposed populations. This investigation evaluates the capability of a simple polymeric detection scheme for PFAS based on crosslinked, thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) hydrogels. Surveying swelling perturbations induced by several hydrotropes and comparable hydrocarbon analogs, tetraethylammonium perfluorooctane sulfonate (TPFOS) showed a significantly higher swelling ratio on a mass basis (65.5 ± 8.8 at 15°C) than any of the other analytes tested. Combining swelling with the fluorimetric response of a solvachromatic dye, nile red, revealed the fluorosurfactant to initiate observable aggregation (i.e., its critical aggregation concentration) at 0.05 mM and reach saturation (i.e., its charge neutralization concentration) at 0.5 mM. The fluorosurfactant was found to homogeneously distribute throughout the polymer matrix with energy dispersive X-ray spectroscopy, marking the swelling response as a peculiar nexus of fluorinated interfacial positioning and delocalized electrostatic repulsion. Results from the current study hold promise for exploiting the physiochemical response of PNIPAM to assess TPFOS's concentration. 相似文献
96.
Journal of Applied and Industrial Mathematics - We consider transformations of three-valued random variables by functions of the three-valued logic. For arbitrary systems of bivariate functions... 相似文献
97.
Journal of Experimental and Theoretical Physics - The studies of the topological properties of systems have recently been extended due to a new concept of higher-order topological insulators and... 相似文献
98.
Theoretical and Mathematical Physics - We review the correspondence between integrable sigma models with complex homogeneous target spaces and the chiral bosonic (and possibly mixed... 相似文献
99.
Gubanova G. N. Timpu D. Cristea M. Kononova S. V. Korytkova E. N. Sapegin D. A. Saprykina N. N. Volkov A. Ya. Klechkovskaya V. V. 《Crystallography Reports》2021,66(7):1185-1199
Crystallography Reports - A new polymer-inorganic nanocomposite composed of fibrous Na–Mg triple chain hydrosilicate with a poly(amide-imide) matrix was developed. Its structure, morphology,... 相似文献
100.
Technical Physics - The effect of power-frequency (50 Hz) electromagnetic field on variation in the physicochemical properties of aluminum powders with different dispersities is studied. It is... 相似文献