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Single-walled carbon nanotubes were treated with ozone through the UV-ozone irradiation to improve their dispersion in poly(vinyl alcohol) matrix. The untreated single-walled carbon nanotubes-poly(vinyl alcohol) and ozone-treated single-walled carbon nanotubes-poly(vinyl alcohol) nanocomposites were prepared at 1% single-walled carbon nanotubes by weight to evaluate the effect of ozone treatment on the rheological, electrical, and thermal properties of poly(vinyl alcohol)-based single-walled carbon nanotube nanocomposites. Rheological results such as storage modulus, loss modulus and loss tangent indicated that incorporation of ozone-treated single-walled carbon nanotubes into poly(vinyl alcohol) up to 1% (by wt.) significantly improved the interfacial bonding between carbon nanotubes and polymer. Electrical results revealed that ozone treatment of single-walled carbon nanotubes improved the dispersion of single-walled carbon nanotubes in neat poly(vinyl alcohol) and reduced the distance between carbon nanotubes in carbon nanotubes-polymer network and as a result the electrical conductivity increased up to four orders of magnitude compared with neat poly(vinyl alcohol). Differential scanning calorimetric results showed that combining ozone-treated single-walled carbon nanotubes (1% by wt.) with poly(vinyl alcohol) enhanced the melting temperature and degree of crystallinity of the neat poly(vinyl alcohol).

We represent an applicable problem that arises when long chain surfactant fatty alcohol sulfate FAS is used in washing process. Octadecyl fatty alcohol sulfate C18-FAS is known for its strong washing performance, however it has the disadvantages of high Krafft point and its long dissolution rate. We demonstrate the factors that affect dissolution rates of FAS-surfactants, and how one can vary these factors in order to achieve particular dissolution rate. In this study, we have used a reproducible method for determining the rate of dissolution of anionic surfactants tablet and the effect of, temperature, hardness of FAS-tablets, stirring rate, FAS chain length, mixing with other surfactants and additives on the rate of dissolution of FAS have been studied.

Schiff base diethyl 4,4-(pentane-2,4-diylidenebis(azanylylidene))benzoate (1) as a new ligand (L) was prepared by the reaction of acetylacetone with benzocaine in the ratio of 1 : 1. Two transition-metal complexes, [Ni(II)(LCl(HOEt))] (2) and [Zn(II)(LCl(HOEt))] (3), have been synthesized from metal salts with didentate Schiff base ligand (L) and characterized by elemental analyses, FT-IR, 1 H NMR, 13 C NMR UV-Vis spectroscopy, and magnetic susceptibility. e biological activity of the complexes was studied. In addition, the M06-2x density function theory method and the 6-31G(d) basic set were applied to determine the optimized structures of 1-3 and to determine their IR and 1 H NMR, 13 C NMR spectra theoretically. e data are in good agreement with the experimental results. e geometries of complexes 2 and 3 were determined to be square-planar for 2 and tetrahedral for 3.

A new Schiff base, 4-((1E,2E)-3-(furan-2-yl)allylidene)amino)-N-(5-methylisoxazol-3-yl) benzene-sulfonamide (L), was synthesized by thermal condensation of 3-(2-furyl)acrolein and sulfamethoxazole (SMX), and the furan Schiff base (L) was converted to a phenol Schiff base (L’) according to the Diels–Alder [4 + 2] cycloaddition reaction and studied experimentally. The structural and spectroscopic properties of the Schiff base were also corroborated by utilizing density functional theory (DFT) calculations. Furthermore, a series of lanthanide and transition metal complexes of the Schiff base were synthesized from the nitrate salts of Gd, Sm, Nd, and Zn (L1, L2, L3, and L4), respectively. Various spectroscopic studies confirmed the chemical structures of the Schiff-base ligand and its complexes. Based on the spectral studies, a nine-coordinated geometry was assigned to the lanthanide complexes and a six-coordinated geometry to the zinc complex. The elemental analysis data confirmed the suggested structure of the metal complexes, and the TGA studies confirmed the presence of one coordinated water molecule in the lanthanide complexes and one crystalline water molecule in the zinc complex; in addition, the conductivity showed the neutral nature of the complexes. Therefore, it is suggested that the ligand acts as a bidentate through coordinates to each metal atom by the isoxazole nitrogen and oxygen atoms of the sulfur dioxide moiety of the SMX based on FTIR studies. The ligand and its complexes were tested for their anti-inflammatory, anti-hemolytic, and antioxidant activities by various colorimetric methods. These complexes were found to exhibit potential effects of the selected biological activities.