The primary photolysis dynamics of oxalate in aqueous solution: decarboxylation

2021 ◽  
Author(s):  
Jan ThOgersen ◽  
Tobias Weidner ◽  
Frank Jensen
Keyword(s):  
Aqueous Solution ◽  
Reaction Dynamics ◽  
Primary Reaction

We study the primary reaction dynamics of aqueous oxalate following photo-excitation of the nO -> πCO* transition at λ = 200 nm. After the excitation, part of the oxalate molecules...

Degradation of Aqueous 4-Chloroaniline by Ozonolysis and Combined γ-Rays-Ozone Processing

2002 ◽  
Vol 57 (11-12) ◽  
pp. 1047-1050
Author(s):  
Mónica Sánchez ◽  
Nikola Getoff ◽  
Laszlo Sümegi ◽  
Robert Zona
Keyword(s):  
Aqueous Solution ◽  
Carboxylic Acids ◽  
Absorption Spectroscopy ◽  
Ozone Concentration ◽  
Degradation Process ◽  
Hplc Method ◽  
Prolonged Treatment ◽  
Primary Reaction ◽  
Γ Irradiation ◽  
Γ Rays

The decomposition of 4-chloroaniline (4-ClA), used as a model for water pollutants, was studied by ozonolysis as well as by γ-rays in the presence of ozone under comparable conditions. The degradation process was followed by absorption spectroscopy and by HPLC-method as well. Depending on the ozone concentration (mg O3/min) introduced into the aqueous solution the substrate is decomposed to a mixture of carboxylic acids, which can be entirely degradated by prolonged treatment. The combined processing of 4-ClA by γ-irradiation in the presence of ozone proved to lead even to more efficient degradation of the substrate. Some primary reaction steps are briefly discussed.

Primary Reaction Dynamics of Proteorhodopsin Mutant D97N Observed by Femtosecond Infrared and Visible Spectroscopy

2009 ◽  
Vol 85 (2) ◽  
pp. 540-546 ◽  
Author(s):  
Mirka-Kristin Verhoefen ◽  
Karsten Neumann ◽  
Ingrid Weber ◽  
Clemens Glaubitz ◽  
Josef Wachtveitl
Keyword(s):  
Reaction Dynamics ◽  
Primary Reaction ◽  
Visible Spectroscopy

Primary reaction dynamics of halorhodopsin, observed by sub-picosecond IR – vibrational spectroscopy

2006 ◽  
Vol 323 (1) ◽  
pp. 109-116 ◽  
Author(s):  
Frank Peters ◽  
Johannes Herbst ◽  
Jörg Tittor ◽  
Dieter Oesterhelt ◽  
Rolf Diller
Keyword(s):  
Vibrational Spectroscopy ◽  
Reaction Dynamics ◽  
Primary Reaction

scholarly journals 3P226 Ultrafast Pump-Probe Study of Primary Reaction Dynamics of Halorhodopsin : Halide Dependence and Isomerization Dynamics(Photobiology- vision and photoreception,Poster Presentations)

2007 ◽  
Vol 47 (supplement) ◽  
pp. S259
Author(s):  
Takumi Nakamura ◽  
Satoshi Takeuchi ◽  
Mikihiro Shibata ◽  
Makoto Demura ◽  
Hideki Kandori ◽  
...  
Keyword(s):  
Reaction Dynamics ◽  
Primary Reaction ◽  
Pump Probe ◽  
Poster Presentations

Structures Formed by Cryoprotective Agents Used in Freezc-Etching

1971 ◽  
Vol 29 ◽  
pp. 448-449
Author(s):  
G. G. Cocks ◽  
C. E. Cluthe
Keyword(s):  
Aqueous Solution ◽  
Polyethylene Oxide ◽  
Liquid Nitrogen Temperature ◽  
Ice Crystals ◽  
Etching Technique ◽  
Structural Constituent ◽  
Cryoprotective Agents ◽  
Quick Freezing ◽  
Freeze Etching ◽  
Fractured Surface

The freeze etching technique is potentially useful for examining dilute solutions or suspensions of macromolecular materials. Quick freezing of aqueous solutions in Freon or propane at or near liquid nitrogen temperature produces relatively large ice crystals and these crystals may damage the structures to be examined. Cryoprotective agents may reduce damage to the specimem, hut their use often results in the formation of a different set of specimem artifacts.In a study of the structure of polyethylene oxide gels glycerol and sucrose were used as cryoprotective agents. The experiments reported here show some of the structures which can appear when these cryoprotective agents are used.Figure 1 shows a fractured surface of a frozen 25% aqueous solution of sucrose. The branches of dendritic ice crystals surrounded hy ice-sucrose eutectic can be seen. When this fractured surface is etched the ice in the dendrites sublimes giving the type of structure shown in Figure 2. The ice-sucrose eutectic etches much more slowly. It is the smooth continuous structural constituent surrounding the branches of the dendrites.

Preparation and characterisation of vanadium pentoxide supported rhodium catalyst

1988 ◽  
Vol 46 ◽  
pp. 946-947
Author(s):  
A. Legrouri
Keyword(s):  
Aqueous Solution ◽  
Thermal Decomposition ◽  
Physicochemical Properties ◽  
Surface Area ◽  
Vanadium Pentoxide ◽  
High Purity ◽  
Gas Adsorption ◽  
Rhodium Catalyst ◽  
Optical Methods ◽  
Reducible Oxides

The industrial importance of metal catalysts supported on reducible oxides has stimulated considerable interest during the last few years. This presentation reports on the study of the physicochemical properties of metallic rhodium supported on vanadium pentoxide (Rh/V2O5). Electron optical methods, in conjunction with other techniques, were used to characterise the catalyst before its use in the hydrogenolysis of butane; a reaction for which Rh metal is known to be among the most active catalysts.V2O5 powder was prepared by thermal decomposition of high purity ammonium metavanadate in air at 400 °C for 2 hours. Previous studies of the microstructure of this compound, by HREM, SEM and gas adsorption, showed it to be non— porous with a very low surface area of 6m2/g3. The metal loading of the catalyst used was lwt%Rh on V2Q5. It was prepared by wet impregnating the support with an aqueous solution of RhCI3.3H2O.

TEM observation of iron oxide pillars in montmorillonite

1990 ◽  
Vol 48 (4) ◽  
pp. 882-883
Author(s):  
H. Mori ◽  
Y. Murata ◽  
H. Yoneyama ◽  
H. Fujita
Keyword(s):  
Aqueous Solution ◽  
Iron Oxide ◽  
Fine Particles ◽  
Aqueous Suspension ◽  
Volume Ratio ◽  
Exchange Capacity ◽  
Nano Composites ◽  
Pillared Montmorillonite ◽  
Topographic Features ◽  
Transmission Electron

Recently, a new sort of nano-composites has been prepared by incorporating such fine particles as metal oxide microcrystallites and organic polymers into the interlayer space of montmorillonite. Owing to their extremely large specific surface area, the nano-composites are finding wide application[1∼3]. However, the topographic features of the microstructures have not been elucidated as yet In the present work, the microstructures of iron oxide-pillared montmorillonite have been investigated by high-resolution transmission electron microscopy.Iron oxide-pillared montmorillonite was prepared through the procedure essentially the same as that reported by Yamanaka et al. Firstly, 0.125 M aqueous solution of trinuclear acetato-hydroxo iron(III) nitrate, [Fe3(OCOCH3)7 OH.2H2O]NO3, was prepared and then the solution was mixed with an aqueous suspension of 1 wt% clay by continuously stirring at 308 K. The final volume ratio of the latter aqueous solution to the former was 0.4. The clay used was sodium montmorillonite (Kunimine Industrial Co.), having a cation exchange capacity of 100 mequiv/100g. The montmorillonite in the mixed suspension was then centrifuged, followed by washing with deionized water. The washed samples were spread on glass plates, air dried, and then annealed at 673 K for 72 ks in air. The resultant film products were approximately 20 μm in thickness and brown in color.

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