Homogeneous hydrolysis of 4,4’-Methylenediphenyl diisocyanate (MDI) in water

A water soluble arabogalactan isolated from jack pine was shown to have a molar ratio of arabinose to galactose of 1:13, and a number average degree of polymerization of 53 ± 3. Fractionation data and electrophoresis indicated that the arabogalactan was homogeneous. Hydrolysis of the methyl ether of the polysaccharide yielded 2,3,5-tri-O-methyl-L-arabinose (4 moles); 2,3,4,6-tetra-O-methyl-D-galactose (12–13 moles); 2,3,4-tri-O-methyl-D-galactose (19 moles); 2,6-di-O-methyl-D-galactose (1 mole); and 2,4-di-O-methyl-D-galactose (14 moles). Some features of the structure of the arabogalactan are discussed on the basis of these results.

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Kinetic isotope effects and intermediate formation for the aqueous alkaline homogeneous hydrolysis of 1,3,5-triaza-1,3,5-trinitrocyclohexane (RDX)

The Journal of Physical Chemistry ◽

10.1021/j100520a003 ◽

1977 ◽

Vol 81 (5) ◽

pp. 380-385 ◽

Cited By ~ 52

Author(s):

John C. Hoffsommer ◽

Donald A. Kubose ◽

Donald J. Glover

Keyword(s):

Isotope Effects ◽

Intermediate Formation ◽

Kinetic Isotope Effects ◽

Kinetic Isotope ◽

Hydrolysis Of ◽

Homogeneous Hydrolysis

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Mechanism of formation of finely dispersed zinc oxide in homogeneous hydrolysis of zinc nitrate in the presence of hexamethylenetetramine

Doklady Chemistry ◽

10.1134/s0012500809050036 ◽

2009 ◽

Vol 426 (1) ◽

pp. 101-104 ◽

Cited By ~ 2

Author(s):

A. S. Shaporev ◽

H. Zeng ◽

V. K. Ivanov ◽

Yu. D. Tret’yakov

Keyword(s):

Zinc Oxide ◽

Zinc Nitrate ◽

Mechanism Of Formation ◽

Hydrolysis Of ◽

Homogeneous Hydrolysis

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Impact of Ge4+Ion as Structural Dopant of Ti4+in Anatase: Crystallographic Translation, Photocatalytic Behavior, and Efficiency under UV and VIS Irradiation

Journal of Nanomaterials ◽

10.1155/2012/252894 ◽

2012 ◽

Vol 2012 ◽

pp. 1-11 ◽

Cited By ~ 5

Author(s):

Václav Štengl ◽

Tomáš Matys Grygar ◽

Jana Velická ◽

Jiří Henych ◽

Snejana Bakardjieva

Keyword(s):

Dye Degradation ◽

Structural Evolution ◽

X Ray Diffraction ◽

X Ray ◽

Oxide Powders ◽

Raman And Infrared Spectroscopy ◽

Nanometric Particles ◽

Hydrolysis Of ◽

Ge Doping ◽

Homogeneous Hydrolysis

Nanometric particles of germanium-doped TiO2were prepared by homogeneous hydrolysis of TiOSO4and GeCl4in an aqueous solution using urea as the precipitation agent. Structural evolution during heating of these starting Ge-Ti oxide powders was studied by X-ray diffraction (XRD) and high-temperature X-ray powder diffraction (HTXRD). The morphology and microstructure changes were monitored by means of scanning electron microscopy (SEM), Raman and infrared spectroscopy (IR), specific surface area (BET), and porosity determination (BJH). The photocatalytic activity of all samples was determined by decomposition of Orange II dye under irradiation at 365 nm and 400 nm. Moderate doping with concentration upto value 2.05 wt.% positively influences azo dye degradation under UV and Vis light. Further improvement cannot be achieved by higher Ge doping. Effect of the annealing (200, 400, and 700°C) on photocatalysis and other properties has been assessed.

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STUDIES ON RDX AND RELATED COMPOUNDS: VI. THE HOMOGENEOUS HYDROLYSIS OF CYCLOTRIMETHYLENETRINITRAMINE (RDX) AND CYCLOTETRAMETHYLENETETRANITRAMINE (HMX) IN AQUEOUS ACETONE, AND ITS APPLICATION TO ANALYSIS OF HMX IN RDX(B)

Canadian Journal of Chemistry ◽

10.1139/v51-084 ◽

1951 ◽

Vol 29 (9) ◽

pp. 731-733 ◽

Cited By ~ 10

Author(s):

S. Epstein ◽

C. A. Winkler

Keyword(s):

Reaction Time ◽

Alkaline Hydrolysis ◽

Activation Energies ◽

Aqueous Acetone ◽

Second Order ◽

Alkali Concentration ◽

Calibration Curves ◽

Hydrolysis Of ◽

Related Compounds ◽

Homogeneous Hydrolysis

Measurements of the rates of alkaline hydrolysis of cyclotrimethylenetrinitramine (RDX) and cyclotetramethylenetetranitramine (HMX) in aqueous acetone show these two reactions to involve consecutive steps, the first of which is second order and rate controlling. Activation energies were estimated as 14 and 25 kcal. respectively. By establishing calibration curves, and controlling temperature, alkali concentration relative to concentration of explosive, and reaction time, the differential hydrolysis permits analysis of the HMX content of RDX(B) with an error of approximately ±0.2% HMX.

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Improvement of Orange II Photobleaching by Moderate Ga3+Doping of Titania and Detrimental Effect of Structural Disorder on Ga Overloading

Journal of Nanomaterials ◽

10.1155/2014/468271 ◽

2014 ◽

Vol 2014 ◽

pp. 1-11

Author(s):

Václav Štengl ◽

Jiří Henych ◽

Michaela Slušná ◽

Tomáš Matys Grygar ◽

Jana Velická ◽

...

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Detrimental Effect ◽

Structural Disorder ◽

Orange Ii ◽

Phase Content ◽

Titania Sample ◽

Hydrolysis Of ◽

Positive Effect ◽

Homogeneous Hydrolysis

Highly photoactive Ga3+-doped anatase modification of titania was prepared by homogeneous hydrolysis of aqueous solutions mixture of titanium oxo-sulphate TiOSO4and gallium(III) nitrate with urea. Incorporation of Ga3+into the anatase lattice has a clear positive effect on the photocatalytic activity under UV and Vis light irradiation up to a certain extent of Ga. Ga3+doping decreased the size of the crystallites, increased surface area, and affected texture of the samples. Higher amount of gallium leads to the formation of a nondiffractive phase, probably photocatalytically inactive. The titania sample with 2.18 wt.% Ge3+had the highest activity during the photocatalysed degradation in the UV and visible light regions; the total bleaching of dye Orange II was achieved within 29 minutes. Ga concentration larger than 5% (up to 15%) significantly inhibited the growth of the anatase crystal domains which formed the nondiffractive phase content and led to remarkable worsening of the photobleaching efficiency.

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