Shizhou Fu

(E)-1-[4-(Dimethyl­amino)benzyl­idene]thio­semicarbazide

In the title molecule, C10H14N4S, the thiorea plane and benzene ring form a dihedral angle of 16.0 (3) Å. In the crystal structure, intermolecular N—H⋯S hydrogen bonds link the molecules into ribbons extended in the [100] direction; these incorporate inversion dimers.

1-Hexadecyl-3-methyl-imidazolium bromide monohydrate.

In the crystal structure of the title compound, C20H39N2 +·Br−·H2O, the 1-hexadecyl-3-methylimidazolium cations are stacked along the b axis, forming channels parallel to [100] which are occupied by the bromide anions and water molecules. The crystal is stabilized by O—H⋯Br, C—H⋯O and C—H⋯Br hydrogen-bonding interactions, generating a two-dimensional network.

The Influences of Polymers and Temperature on the Foam Properties of 3‐Dodecylalkoxyl‐2‐hydroxylpropyl Trimethylammonium Chloride

The foam performances of 3‐dodecoxy‐2‐hydroxypropyl trimethylammonium chloride (C12TAC) have been determined in the existence of different relative amount of polymer. The experimental results show that the foaming ability of the mixture systems of the C12TAC/PEG and C12TAC/PVP is stronger than that of the surfactant solutions in the absence of polymer, and with the increase of relative amount of polymer both foaming efficiency and foam stability of the surfactant solutions are evidently enhanced. For the aqueous solution of the surfactant, effect of temperature on foaming properties has also been examined. The results show that both the foaming ability and stability of the foams of the surfactant solutions are highest (or strongest) at 30°C.

Study on Surface Activity and Bacteriostasis of a Series of Gemini Cationic Surfactants

N, N′-didodecyl-2-hydrxyl-N, N, N′N′-tetramethyl-dichloride has been synthesized with R (CH3)2N (R = CnH2n+1, n = 12, 14, 16), hydrogen chloride and epoxy chloropropane as raw materials. The products have been characterized by element analysis and 1H NMR spectra. Fundamental interfacial behavior of the surfactant at the air/water interface has been investigated by means of surface tension measurements to provide an insight into relationship between the structure of the hydrophobic moiety and the surfactant properties. Foam performance and bacteriostasis in aqueous solution have been investigated. The results indicate that the gemini cationic surfactants have strong surface activity. The surface activity is relevant to the number of carbon atoms in the hydrophobic tail of surfactant molecule. The longer the alkyl chain is, the stronger the surface activity and the lower the critical micelle concentration will be. G12Cl2 solution possesses the best performance of the foaming ability and foam stability at 298.15 K, but bubbly and stability efficiency is the lowest among the three systems. Bacteriostasis of the surfactants has been determined with disk diffusion on filter paper. The results show that all of the newly synthesized double quaternary ammoniums possess quite good bacteriostasis.

Studies of Phase Behavior on R12TAB/Benzyl Alcohol/Water Ternary System

Phase behavior of ternary systems containing 3‐dodecyloxy‐2‐hydroxypropyl trimethyl ammonium bromide (R12TAB), benzyl alcohol and water have been studied at 25±0.1°C. Ternary phase diagram of the systems shows a clear, isotropic, and low‐viscous region, a L phase, two liquid crystalline phases (lamella and hexagonal liquid crystal), and a coexisted phase of the liquid crystalline and micelles. 2H nuclear magnetic resonance (2H NMR) technology and polarizing‐light microscope were employed to confirm the symmetry structure of the liquid crystals and the boundaries for the different phases. In L phase, three types of different micelle regions (reverse micelles, normal micelles, and bicontinuous structures zones) were confirmed by means of the electric conductivity and the proton nuclear magnetic resonance spectroscopy (1H NMR) measurements. The microcosmic structures of the micelle were investigated, and the solubilizing position of benzyl alcohol were located according to the chemical shift of protons.

Erratum: 2-Hydr-oxy-N'-[(E)-(3-hydr-oxy-2-naphth-yl)methyl-ene]benzohydrazide. Corrigendum.

Corrigendum to Acta Cryst. (2009), E65, o262.