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The binding characteristics of phenanthrene with dissolved organic matter (DOM) were studied by the excitation emission matrix fluorescence spectroscopy with parallel factor analysis in four types of land use which derived from forest (F), meadow (M), cropland (C), and greenhouse (G). The results showed that the humification degree and binding characteristics of phenanthrene with DOM were distinct differences in the four soils. The binding capacities of humic-like components with phenanthrene were stronger than those of protein-like components. The log K derived from the Stern-Volmer equation significantly correlated with the humification degree of DOM ( p < 0.05) in different types of land use. Besides, correlation analysis demonstrated that the potential binding index (Fk) obtained from the modified Stern-Volmer model was a more accurate parameter to describe the combination degree of DOM with phenanthrene than log K , which presented a decrease order of C > F > M > G. Therefore, the environmental impact of phenanthrene in different types of land use could be assessed deeply based on the Fk and DOM concentration. [ABSTRACT FROM AUTHOR]

Since solvents of petroleum origin are now strictly regulated worldwide, there is a growing demand for using greener, bio-based and renewable solvents for extraction, purification and formulation of natural and food products. The ideal alternative solvents are non-volatile organic compounds (VOCs) that have high dissolving power and flash point, together with low toxicity and less environmental impact. They should be obtained from renewable resources at a reasonable price and be easy to recycle. Based on the principles of Green Chemistry and Green Engineering, vegetable oils could become an ideal alternative solvent to extract compounds for purification, enrichment, or even pollution remediation. This review presents an overview of vegetable oils as solvents enriched with various bioactive compounds from natural resources, as well as the relationship between dissolving power of non-polar and polar bioactive components with the function of fatty acids and/or lipid classes in vegetable oils, and other minor components. A focus on simulation of solvent-solute interactions and a discussion of polar paradox theory propose a mechanism explaining the phenomena of dissolving polar and non-polar bioactive components in vegetable oils as green solvents with variable polarity. [ABSTRACT FROM AUTHOR]

In order to improve the sonocatalytic activity of TiO2, Al2O3/TiO2, Y2O3/TiO2 and Fe2O3/TiO2 composites were prepared using mechanical mixing, liquid boiling, ultrasonic dispersion and heat-treated methods. And then, a series of degradation experiments were carried out under ultrasonic irradiation. Also, the influences of heat-treated temperature and heat-treated time on the sonocatalytic activity of Al2O3/TiO2, Y2O3/TiO2 and Fe2O3/TiO2, and ultrasonic irradiation time and solution acidity on the sonocatalytic degradation of Acid red B were investigated by UV-vis spectra. It was found that the degradation ratio showed significant increase in the order TiO2 < Fe2O3/TiO2 < Y2O3/TiO2 < Al2O3/TiO2. And the corresponding percentage degradations are about 37, 45, 52 and 81%, respectively. In addition, for exploring the universality, the degradation of other several organic dyes was also reviewed under the same conditions. Because of good degradation efficiency, this method may be an advisable choice for the treatment of non- or low-transparent wastewaters in the future. [ABSTRACT FROM AUTHOR]

E-(4- β-D-Allopyranosyloxyphenyl)-1-(4-substituted phenyl)propenone derivatives ( 1a–g) have been synthesized by the Claisen-Schmidt condensation of helicid with 4-substituted acetophenone using 10% NaOH aqueous solution as a catalyst. 6 H-2-Amino-4-aryl-6-(4- β-D-allopyranosyloxyphenyl)-1,3-thiazine ( 2a–g) were synthesized by the 1,4-Michael reaction of 1a–g with thiourea. The structures of all the new products were established by 1H NMR, IR, and MS spectroscopy. Compound 2b (200 mg·kg–1) showed better sedative-hypnotic activity, so further modification of helicid should be worthwhile. [ABSTRACT FROM AUTHOR]

Biodegradable glycerol-derived alkyd resins were synthesized from glycerol and maleic anhydride by polycondensation reactions. One set of glycerol-derived alkyd resin/clay nanocomposites was successfully prepared by melt blending maleic anhydride-glycerol precursors with organoclays. These clays had been pretreated with methyl tallow bis-2-hydroxylethyl ammonium chloride salt (yielding a nanocomposite designated clay30B), and some samples of the clay30B were further treated with the diglycidyl ether of bisphenol A (DGEBA) (clay30BT). Resin/mica and resin/talc nanocomposites were also prepared, in the same way, to yield materials for purposes of comparison. The morphologies, thermostabilities, and mechanical properties of the resulting nanocomposites were investigated in detail. X-ray scattering results and transmission electron microscopy (TEM) images clearly indicated that 30BT was further delaminated by the DGEBA, and that the clay30B and clay30BT were mostly exfoliated and finely distributed in the alkyd resin matrix. These layered silicate fillers gave remarkable improvements in thermostability and mechanical properties even at very low loadings. Minimizing aggregation was more of a problem in the case of the mica and the talc, at least in this matrix. [ABSTRACT FROM AUTHOR]

A series of poly(aryl ether) dendrimers (Py−Gn−NHPh, n1−4) with only one pyrene chromophore at the periphery and an aniline group at the core were synthesized and the extent of folding back conformation was given by the intramolecular electron transfer and exciplex formation. Selective excitation of the periphery pyrene moiety of Py−Gn−NHPh in dichloromethane resulted in an electron-transfer process from aniline to pyrene, and as a consequence of the electron transfer, an intramolecular exciplex was formed. Since the exciplex formation requires a direct orbital overlap between the donor and the acceptor groups, this gives us a direct experimental observation for the folding back conformation of poly(aryl ether) dendrimers. The efficiencies and the rate constants of electron transfer in dichloromethane are measured to be 0.90, 0.83, 0.78, 0.68, and 3.6 × 108, 1.7 × 108, 1.2 × 108, and 6.6 × 107s-1for generations 1−4, respectively. The separations (center to center) between the core donor group and the periphery acceptor chromophore are estimated from the rate constants of electron transfer, which are 7.7, 8.0, 8.2, and 8.5 Å for generations 1−4, respectively. This means that the periphery chromophores can fold inward and reach to the core vicinity for all four generations. [ABSTRACT FROM AUTHOR]

In the molecule of the title compound, C16H15NO, all bond lengths and angles are within normal ranges. The dihedral angle between the two aromatic rings is of 62.80 (1)°. The crystal packing is stabilized by C—H⋯ interactions. [ABSTRACT FROM AUTHOR]

A novel technique for the fabrication of tin-doped indium oxide (ITO) fine patterning in sol-gel technology is presented in this paper. The fabricated ITO fine patterning could be obtained through a process which combines film fabrication with film etching. ITO films have good comprehensive property of visible transmittance and electrical conductivity, consequently they have been extensively used as coating electrodes. Indium nitrate (In(NO3)3.4.5H2 O) and stannic chloride ( SnCl4.5H2O) were used as starting materials which were modified with benzytone (BzAcH). The chelate complexes containing indium ions were produced during the process which of forming photosensitive ITO/BzAcH gel films through sol-gel technique. It was found that the gel films are sensitive to both the ultraviolet (UV) light irradiation and their solubility on solvents as well. For example, ethanol was reduced remarkably while the UV absorption peak disappeared with the dissociation of the chelate complexes correspondingly by means of UV-vis and IR spectrophotometers. Utilizing these characteristics, a fine pattern was obtained by irradiation of UV light on the ITO/BzAcH gel films through a pattern mask. of the fine patterned ITO films were heat treated at 500degC for 15 min, the optical, electrical properties and the surface element components were examined by X-ray photoelectron spectroscopy (XPS) spectra in this work [ABSTRACT FROM PUBLISHER]

Coordination of unsaturated [In(amine)]3+ onto indium telluride structure, where the complex ion has higher positive charge, not only forms an organic-inorganic hybrid polymeric structure, but also offers an indium telluride with positive charge. Based on this strategy, cationic networks of metal chalcogenide may be expected. [ABSTRACT FROM AUTHOR]

In the presence of sodium hydrosulfite and a catalytic amount of AsPh3 and Fe(TCP)Cl, aldehydes react with ethyl diazo-acetate to give the corresponding α,/β-unsaturated esters in high yields with excellent stereoselectivities (E/Z > 50/1). [ABSTRACT FROM AUTHOR]

The rectification ratio of organic magnetic co-oligomer diodes is investigated theoretically by changing the molecular length. The results reveal two distinct length dependences of the rectification ratio: for a short molecular diode, the charge-current rectification changes little with the increase of molecular length, while the spin-current rectification is weakened sharply by the length; for a long molecular diode, both the charge-current and spin-current rectification ratios increase quickly with the length. The two kinds of dependence switch at a specific length accompanied with an inversion of the rectifying direction. The molecular ortibals and spin-resolved transmission analysis indicate that the dominant mechanism of rectification suffers a change at this specific length, that is, from asymmetric shift of molecular eigenlevels to asymmetric spatial localization of wave functions upon the reversal of bias. This work demonstrates a feasible way to control the rectification in organic co-oligomer spin diodes by adjusting the molecular length. [ABSTRACT FROM AUTHOR]

The title compound, C15H15N3S, was prepared by the reaction of acetophenone and hydrazine with phenyl­isothio­cyanate. In the mol­ecule, all bond lengths and angles are within normal ranges. The two phen­yl rings make a dihedral angle of 61.6 (2)°. The crystal packing is stabilized by van der Waals forces. [ABSTRACT FROM AUTHOR]

The title compound, [Sn4(CH3)8(C6H5N2O2)4O2]·6H2O, is a hydrated cluster containing four Sn atoms, built up by inversion symmetry around the central Sn2O2 ring. The Sn-atom coordination geometry might be regarded as very distorted SnO3C2 trigonal–bipyramidal or possibly as grossly distorted SnO3C2N octahedral. All the cluster non-H atoms, with the exception of the Sn-bonded methyl groups, lie on a mirror plane. Two of the water-molecule O atoms have m site symmetry; the other occupies a twofold rotation axis. [ABSTRACT FROM AUTHOR]

In the mol­ecule of the title compound, C12H11N3OS, the dihedral angle between the planar rings is 59.4 (2)°. The structure is stabilized by intra­molecular N—H⋯N and inter­molecular N—H⋯S hydrogen bonds. Inter­molecular N—H⋯S hydrogen bonds link the independent mol­ecules into dimers. [ABSTRACT FROM AUTHOR]

Abstract: The selective oxidation of alcohols with molecular oxygen was efficiently completed in high conversion and selectivity using HPW/MCM-41 as a heterogeneous photocatalyst in ionic liquids, [bmim]PF6, [omim]BF4 and [hmim]BF4. Comparative studies on the catalytic properties of HPW/MCM-41, HPW to MCM-41 were carried out. Some important variables, e.g. the loading amount of HPW on MCM-41 and the effects of different ionic liquids were discussed in this work. [Copyright &y& Elsevier]

In the title compound, C12H12ClN5O3S, the pyrazole ring and the benzene ring are approximately coplanar. The mean plane of the pyrazole ring makes a dihedral angle of 12.82 (13)° with the mean plane of the benzene ring. The crystal packing is stabilized by intramolecular N—H...O and intermolecular N—H...O and N—H...N hydrogen bonds. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title compound, C19H14N2O2, the molecules are almost planar. The dihedral angle between the two aromatic ring systems is 3.67 (1)°. [ABSTRACT FROM AUTHOR]

In the title compound, [CdCl2(C18H14N4)] n, the Cd atom displays a distorted octahedral geometry, coordinated by four Cl atoms and two N atoms from a bidentate 10,11,12,13-tetrahydro-4,5,9,14-tetraazabenzo[ b]triphenylene molecule. Each Cl atom bridges two Cd atoms, forming a stair-like polymer along the a axis. [ABSTRACT FROM AUTHOR]

The title compound, C21H20N4O5S, crystallizes with two mol­ecules in the asymmetric unit. The crystal structure is stabilized by a network of C—H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]

In the title compound, C11H10N4O3, the substituted phen­yl ring and the triazole ring make a dihedral angle of 59.7 (2)°. The mol­ecules are linked into zigzag chains by inter­molecular C—H⋯O hydrogen bonds. These chains are further connected through C—H⋯N hydrogen bonds to build up a three-dimensional network. [ABSTRACT FROM AUTHOR]