The complexes of cetyl alcohol, cetomacrogol-1000, and water were successfully synthesized. The complexes were characterized by freeze-drying scanning electron microscopy, small-angle X-ray diffraction (SAXD), and ultra-SAXD. Furthermore, structures, electronic properties (the HOMO–LUMO gap, ionization potential, electron affinity, electronegativity, hardness, softness, dipole moment, and polarizability), and Raman spectra of cetyl alcohol, cetomacrogol-1000, and their binary and ternary complexes with water were also studied using density functional theory. The calculated lengths of hydrophilic heads in the ternary complexes were in good agreement with SAXD data. The results indicated the existence of two types of interlamellar spacings between successive swollen bilayers (approximately 144 and 72 Å) when polyoxyethylene groups of cetomacrogol-1000 molecules were completely hydrated and stretched. Besides, in comparison with the monomers, the ternary complex of cetyl alcohol, cetomacrogol-1000, and water with the molecular ratio of 1:1:1 (cetyl-ceto-H2O-1 complex) had outstanding properties.

A new tetrahydroxanthene-1,3(2H)-dione derivative (1) was isolated from the leaves of Uvaria cordata collected in Viet Nam. Its structure was elucidated to be a mixture of four tautomers (1a-1d) by a combination of extensive spectroscopic analyses and the theoretical calculation of Gibbs free energies. Compound 1 exhibited moderate cytotoxicity against KB, LNCaP, Hep-G2, MKN-7, SW-480, HL-60, and SK-Mel-2 cancer cell lines with IC 50 values ranging from 25.92 ± 2.33 to 44.29 ± 4.36 μg/mL. In addition, the previously reported structure of valderramenol A has been revised to 1a/1b.

No abstract

In this work, noncovalent interactions including hydrogen bonds, C···C, N···O, and van der Waals forces between paracetamol and formaldehyde were investigated using the second-order perturbation theory MP2 in conjunction with the correlation consistent basis sets (aug-cc-pVDZ and aug-cc-pVTZ). Two molecular conformations of paracetamol were considered. Seven equilibrium geometries of dimers were found from the result of the interactions with formaldehyde for each conformation of paracetamol. Interaction energies of complexes with both ZPE and BSSE corrections range from −7.0 to −21.7 kJ mol–1. Topological parameters (such as electron density, its Laplacian, and local electron energy density at the bond critical points) of the bonds from atoms in molecules theory were analyzed in detail. The natural bond orbital analysis showed that the stability of complexes was controlled by noncovalent interactions including O–H···O, N–H···O, C–H···O, C–H···N, C–H···H–C, C···C, and N···O. The red- and blue-shifted hydrogen bonds could both be observed in these complexes. The properties of these interactions were also further examined in water using a polarized continuum model. In water, the stability of the complex was slightly reduced as compared to that in the gas phase.

In this study, we have successfully synthesized electrode materials containing Pt on modified graphite by electrodeposition method, such as: Pt/C, Pt-Au/C Pt-Pd/C, Pt-Ni/C, Pt-Ni-Au/C, Pt-Ni-Pd/C. The formation of materials coating on the modified graphite surface is demonstrated through SEM, EDS results. Synthetic materials are used as catalysts for hydrogen evolution reaction (HER). The results show that Bimetallic composites containing Pt exhibit higher catalytic activity than the monometallic material Pt/C. Trimetallic materials Pt-Ni-Au/C and Pt-Ni-Pd/C have catalytic activity for HER insignificant lower than that of Pt-Au/C and Pt-Pd/C electrodes.  However, the precious metal composition in the trimetallic composite material system is reduced, which is also an important goal of research and opens up prospects for the fabrication of next-generation composite materials systems.