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An ionic liquid, 1-allyl-3-methylimidazolium methyl phosphonate (Amim(MeO)PHO2), was synthesized and used to dissolve and regenerate cellulose under mild conditions. The dissolution mechanism of cellulose in Amim(MeO)PHO2 was investigated by in situ NMR spectroscopy under different conditions. Inorganic salt Na2PHO3 with an anion structure similar to that of Amim(MeO)PHO2 was added to form a Na2PHO3/Amim(MeO)PHO2 composite system. The effects of the composite system on the cellulose structure were investigated by Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, and the measurement of the degree of polymerization. The results indicated that the regenerated cellulose was not derivatized; however, its thermal stability, crystallinity, and DP were lower than that of the original cellulose. Therefore, the dissolution mechanism of cellulose in Amim(MeO)PHO2, and its composite system with Na2PHO3 was investigated in this study, which might provide a simple guide for designing efficient and safe ionic liquids for the dissolution of cellulose.

A series of anion exchange membranes (AEMs) consisting of polyvinyl alcohol/branched polyethyleneimine (PVA/BPEI) were simply prepared by casting method using glutaraldehyde (GA) as crosslinking agent, then quaternized with benzyl chloride and alkalized in KOH solution. Subsequently, the comparative analysis was performed to select the optimal ratio of PVA to BPEI and crosslinking degree of AEMs. The structure and properties of AEMs were verified by FT-IR, XRD, TGA, mechanical analysis, water uptake test, swelling ratio test, ion exchange capacity (IEC) test, ionic conductivity measurement, and alkaline/oxidative stability test. The results showed that the maximum value of ionic conductivity was 86.0 mS/cm at 80 °C with IEC value of 2.35 meq/g. Moreover, the AEM had excellent chemical stability, as the ionic conductivity decreased by

Ibuprofen sodium is the sodium salts form of ibuprofen which exhibits better effects than standard ibuprofen as an analgesic by inhibiting the cyclooxygenase enzyme system. 3-[4-(2-Methylpropyl)phenyl] propanoic acid as one of potential impurities of ibuprofen was determined by a gas chromatography method after the methylation reaction according to the European Pharmacopoeia. Now, a new simple normal phase high-performance liquid chromatography (NP-HPLC) method has been established to separate 3-[4-(2-methylpropyl)phenyl]propanoic acid from ibuprofen sodium as well as from ibuprofen. Separation was performed on an Ultimate Silica column (250 mm × 4.6 mm, 5 μm) using hexane, ethyl acetate and trifluoroacetate in the ratio (97:3:0.95, v/v/v) as mobile phase. The detection wavelength was performed at 264 nm. The NP-HPLC method could successfully separate 3-[4-(2-methylpropyl)phenyl]propanoic acid from the main peak within an analysis time of less than 20 min. Complementary of this work, a forced degradation study was carried out under specified conditions to investigate the chemical stability of ibuprofen sodium. The method was found to be precise, linear, accurate, sensitive, specific and robust according to the ICH guidelines.

Monodisperse CdS nanospheres assembled by small nanoparticles were prepared using dimethyl sulfoxide (DMSO) as a solvent through several routes including thermolysis of xanthate, the reaction of cadmium acetate (Cd(CH3CO2)2) with thiourea, and interfacial reaction of CS2 and Cd(CH3CO2)2/DMSO. The corresponding products possessed the particle sizes ranging from around 35 to 45 nm, 63 to 73 nm, and 240 to 280 nm, respectively. These products presented uniform spherical morphology, which provide insights into the effect of DMSO on CdS morphology. DMSO, as an aprotic and polar solvent, possesses unique properties. The oxygen and sulfur atoms in DMSO can coordinate to metal ions on nanoparticles surface, and the high polarity of DMSO is favorable to fast reaction, nucleation, growth, and Ostwald ripening, forming monodisperse nanospheres with narrow size distribution. The influence of CdS size on its photocatalytic activity was evaluated using Rhodamine B (RhB) as a model compound under visible light irradiation.

The freestanding Sb(2)S(3) films were easily synthesized at the interface of water and toluene at room temperature, where Na(2)S and (C(2)H(5)OCS(2))(3)Sb (xanthate, O-ethyldithiocarbonate) acted as sulfur and antimony source, respectively. After 3 h of aging, the Sb(2)S(3) films with a flat surface toward organic side and rough surface toward aqueous side were assembled by sheaflike Sb(2)S(3) nanowires. The Sb(2)S(3) nanorings formed by end-to-end connection of the bundled nanowires appeared in the water layer when the reaction time reached 24 h. The Sb(2)S(3) nanorings showed higher photocatalytic activity for methyl orange degradation under visible light than the Sb(2)S(3) films owing to broader spectrum response and better aqueous dispersion.

The complex [(C6H11OCS2)(PPh3)2Cu], was synthesized and characterized using IR, UV, and 1H NMR. The crystal and molecular structure has been determined by X-ray diffraction. The yellow crystal of the complex is triclinic of space group \(P\bar 1\), with parameters a=10.370(2)A, b=13.530(3)A, c=14.640(3)A, α=92.60(3)°, β=108.00(3)°, γ=97.70(3)°, and Z=2. In the complex, the central Cu atom is in a distorted tetrahedral environment and chelated by two phosphorus atoms of the TRIPHOS and two sulfur atoms from the O-cyclohexyldithiocarbonate. The cyclohexane ring adopts a chair conformation. The thermal analytical data indicate that the complex begins to decompose at 101°C and stop at 360°C , leaving CuS. IR, UV, and NMR results supported the crystal structure.

The Cu2S dendrites were formed on TEM grids from elemental sulfur (S) in CS2 solution by one day's ageing under ambient conditions and became denser with ageing. The shape and structures were stable in air for at least a month. If S/ethanol solution was dropped on Cu grid, uniform Cu2S nanowires were produced one day later, which could only be obtained by one week's ageing when using S/ethanol suspension as source in our previous work. The influence of the sulfur dispersion and concentration in several kinds of solvent on the growth and structures of Cu2S was discussed based on electron microscopic observation. This simple synthesis method from elemental reactants without any additives was useful for studying formation mechanism of hierarchical nanostructures, and more importantly, it was environmentally friendly.

The crystal and molecular structure of the title compound, [Ni(phen)2(CH3)2CHOCSS](CH3)2CHOCSS has been determined by X-ray diffraction. The brown crystal is triclinic of space group Pi, with parameters a = 11.790(2), b = 12.410(3), c = 12.680(3) A, α = 92.49(3), β = 96.54(3), γ = 117.43(3)° and Z = 2. The compound contains a six-coordinate cation and an isopropyl xanthate anion (CH3)2CHOCSS−, the central Ni atom is chelated by four nitrogen atoms of two phenanthroline ligands and two sulfur atoms of an isopropyl xanthate ligand. The TG data indicate that it decomposed completely at 734°C.

Spherical CuS hierarchical structures organized by nanoparticles were synthesized by the reaction of CuCl 2 ·2H 2 O and sodium O -isopropyldithiocarbonate (xanthate, C 3 H 7 OCSSNa) in N , N -dimethylformamide (DMF) at 70 °C for 12 h. The product was characterized by X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM and TEM). The result shows that the hierarchical CuS spheres were of 300–500 nm and aggregated by numerous particles with an average diameter of about 10 nm. A possible mechanism for the formation of CuS hierarchical structures is proposed, and an optical study has also been carried out.