Ratio Of 2-propanol Research Articles

New efficient lighting device. Part 1. hybrid materials based on inorganic aerogel and metal-organic phosphor

A novel luminescent organic-inorganic hybrid material “LightSil” (hereinafter referred to as HM-LS) has been fabricated. Tris (8-hydroxyquinolate)aluminum (Alq3) purified by vacuum sublimation to 99.999 ​wt% was used as an organic phosphor. Silica aerogel was used as an inorganic matrix. Alq3 intercalation into aerogel structure did not strongly influence on the HM-LS morphology characteristics comparing with the pure aerogel, which indicated that the intercalation had proceed on the molecular level. An aerogel based hybrid was supercritical dried in a carbon dioxide environment under a pressure of 120 ​bar, at 40 ​°C at a carbon dioxide consumption of 500 ​g/h. The synthesis conditions (TEOS:2-propanol ratio) has been optimized to make the HM-LS sample with the best photoluminescence (PL) characteristics. Analysis of the PL spectra showed that the PL peak maximum of HM-LS shifted to longer wavelengths, and the HM-LS spectrum itself broadened by 64%: FWHMAlq3 ​= ​73 ​nm, FWHMHM-LS ​= ​113 ​± ​3 ​nm relative to Alq3 powder PL spectrum. The latter indicated on a change in the electronic structure of Alq3 in HM-LS in comparison with the nominally pure Alq3 and this proved the formation of a new hybrid material.

The Effect of Recycled Solvent on the Structure of Photonic Crystal

Minimizing or avoiding the creation of waste solvents can be most effective in protecting environment and managing the cost. Since fabrication of silica spheres (approximately 1.0 g of silica spheres with diameter of approximately 300 nm) for photonic crystal requires relatively large amount of solvents (100 ml 2-propanol and 100 ml NH4OH solution), it will be ideal to use recycled solvents for reducing waste solvents. Monodisperse silica spheres were synthesized with Stober synthetic process. The diameter of the spheres was uniform when the ratio of 2-propanol and NH4OH was 1:1. To investigate the effect of recycled solvents, the ratio of 2-propanol:NH4OH maintained 1:1. The spheres were separated by filtration or centrifuge. The mixture of solvents was recycled repeatedly after separating the spheres. The spheres became irregular shape when the mixture of solvents recycled by filtration more than twice. The solvent was completely dried and collected the residual compound in the mixture of solvents, which was comprised of mainly –OH and Si-O-Si. However, there was no irregular shape and residual solid in the mixture of solvents after 4 times recycling by centrifuge. These results imply that the filtering process removes NH4OH due to the low pressure during the filtering process, but the centrifuge method requires no low pressure process and maintains similar NH4OH concentration after repeated recycling process. Therefore, the recycled solvent mixture can be repeatedly used as long as similar NH4OH concentration maintains.

A facile approach to nanostructured hollow titania with high photocatalytic activity

Nanostructured hollow titania has been synthesized by a facile hydrothermal method in water/2-propanol mixed solution. The synthesized hollow titania is of anatase phase with a novel worm-like morphology. The wall thickness of this hollow structure can be conveniently controlled from about 100 nm to 380 nm and the inner cavity diameter from 300 nm to 130 nm by changing the water to 2-propanol ratio. The formation of the hollow worm-like titania could be attributed to the microheterogeneity of the water/2-propanol system. Furthermore, the as-synthesized product exhibits higher photocatalytic activity than that of commercial P25 in the methylene blue (MB) degradation reaction.

Separation and quantitation of Z-isomer in lanoconazole by normal phase HPLC

An isocratic normal phase high-performance liquid chromatographic (NP-HPLC) method has been developed and validated for the quantitation of Z-isomer in lanoconazole. Separation was achieved with a Thermo Hypersil Silica column. The ratio of 2-propanol, n-hexane and triethylamine in the mobile phase were optimized to obtain the best separation. UV detection was performed at 296 nm. The described method is linear over a range of LOQ – 15.0 μg/ml of Z-isomer. The mean recovery of Z-isomer was found to be in the range of 97–99%. The method is simple, rapid, selective, accurate and precise, useful in the quality control of bulk manufacturing.

Effects of the addition of 2-propanol on direct liquefaction of wood.

When wood powder was liquefied in an water/2-propanol mixture solution in the presence of sodium carbonate at 250-300°C under pressurized nitrogen, a heavy oil having fluidity was obtained. The effects of temperature, pressure, and water/2-propanol ratio were examined. Under optimum conditions of temperature 275°C, pressure 90atm, water:2-propanol=1:1, the heavy oil yields were 60-70% and the recovery of 2-propanol was about 90%. With respect to the separation ability, when water:2-propanol ratio was 5:1, an oily layer, which could be easily separated from aqueous layer, was directly formed.

Gel filtration medium derived from guar gum

Guar gum gels have been synthesised by cross-linking guar gum with epichlorhydrin in water—2-propanol. The degree of cross-linking was adjusted by controlling three factors: the concentration of guar gum, the amount of cross-linking agent and the water:2-propanol ratio. The preparation and chromatographic evaluation of the two gels, designated guar gel 5-X30 and 2-X10, are described. For these two gels, molecular weight exclusion limits of approximately 15,000 and 70,000, respectively, were observed for globular proteins.