The adsorption and photodegradation of oxalic acid at the TiO2 surface

2007 ◽  
Vol 55 (12) ◽  
pp. 139-145 ◽  
Author(s):  
Cecilia B. Mendive ◽  
Miguel A. Blesa ◽  
Detlef Bahnemann
Keyword(s):  
Oxalic Acid ◽  
Anatase Phase ◽  
Oxalic Acid Solution ◽  
Tio2 Surface ◽  
Adsorbed Species ◽  
Surface Complexes ◽  
Photo Degradation ◽  
Spectral Changes ◽  
Thermal Mechanism ◽  
Exposed Surface Area

ATR–FTIR measurements in combination with quantum chemical calculations were performed to study chemical reactions taking place at the surface of a thin TiO2 layer immersed in an aqueous oxalic acid solution under UV(A) illumination. It was found that the adsorption of oxalic acid on TiO2 in the dark can be explained in terms of two surface complexes for the anatase phase. Under UV(A) illumination, one of the adsorbed species on the anatase phase preferably undergoes photo-degradation and at the same time more molecules of oxalic acid are adsorbed at the TiO2 surface which is thus enriched in the second complexation mode. The spectral changes observed under UV(A) illumination are explained in the light of different theories: photo-desorption of water molecules as a thermal mechanism induced by the absorption of photons, surface reconstruction, and newly exposed surface area provided by the de-aggregation of the TiO2 particles.

Facile synthesis of CuO micro-sheets over Cu foil in oxalic acid solution and their sensing properties towards n-butanol

2016 ◽  
Vol 4 (5) ◽  
pp. 985-990 ◽  
Author(s):  
Chengjun Dong ◽  
Lihong Wang ◽  
Gang Chen ◽  
Xuechun Xiao ◽  
Igor Djerdj ◽  
...  
Keyword(s):  
Oxalic Acid ◽  
Acid Solution ◽  
Oxalic Acid Solution ◽  
Facile Synthesis ◽  
Sensing Properties ◽  
Annealing Procedure ◽  
Cu Foil

Here, CuO micro-sheets were successfully synthesized from Cu foil using the annealing procedure.

Bacteriological research

1930 ◽  
Vol 26 (3) ◽  
pp. 327-327
Author(s):  
A. A. Ozereliev
Keyword(s):  
Oxalic Acid ◽  
Acid Solution ◽  
Oxalic Acid Solution ◽  
Alcoholic Solution ◽  
Operating Field

Abstracts. Surgery. A. A. Ozereliev (Zentralbl. F. Chir. 1930, No. 3) based on a comparison It is recommended to use a 5% alcoholic solution of tannin for disinfection of the operating field, since the latter, with the same disinfecting force with t. jodi does not irritate the skin. To eliminate stains, it is recommended to wash them off after surgery with 1% oxalic acid solution.

scholarly journals Electrochemical synthesis and corrosion protection of poly(3-aminophenylboronic acid-co-pyrrole) on mild steel

RSC Advances ◽  
2020 ◽  
Vol 10 (63) ◽  
pp. 38548-38560
Author(s):  
Hakan Sarıarslan ◽  
Erhan Karaca ◽  
Mutlu Şahin ◽  
Nuran Özçiçek Pekmez
Keyword(s):  
Oxalic Acid ◽  
Acid Solution ◽  
Mild Steel ◽  
Corrosion Protection ◽  
Electrochemical Synthesis ◽  
Oxalic Acid Solution ◽  
Aminophenylboronic Acid

Synthesis of poly(3-aminophenylboronic acid-co-pyrrole) (p(APBA-co-Py)) is carried out potentiodynamically on a pre-passivated mild steel (MS) surface in an oxalic acid solution containing 3-aminophenylboronic acid (APBA) and pyrrole (Py) monomers.

Synthesis and Dispersity of YBCO Powder Produced by Oxalic Acid Precipitation Method

2015 ◽  
Vol 645-646 ◽  
pp. 145-150 ◽  
Author(s):  
Ai Qin Wang ◽  
Hui Hui Han ◽  
Min Li ◽  
Jing Pei Xie ◽  
Qing Jie Wu ◽  
...  
Keyword(s):  
Grain Size ◽  
Oxalic Acid ◽  
Technological Parameter ◽  
Oxalic Acid Solution ◽  
Acid Precipitation ◽  
Precipitation Method ◽  
Test Results ◽  
Ph Values ◽  
Mean Grain Size ◽  
The Mean

The YBCO powder was prepared by oxalic acid precipitation method and consequent annealing. The correlation between pH values of oxalic acid solution and the precipitation percentage of precursors were analysed based on thermodynamics analysis. The differential scanning calorimetryanalysis (DSC) was used to confirm the synthetic technological parameter. The phases of powder in each process were investigated by XRD. The microstructures of each powder were tested by SEM and TEM. The mean grain size was calculated by the scherrer’s equation. The test results indicated that the YBCO powder with high purity, less impurities, smaller particle, but severe agglomeration, was Y123 when annealing at 900°C. However, adding dispersants could effectively solve the severe agglomeration. The size of YBCO particles was nanosized and coincided with the calculation.

scholarly journals High variability of the heterogeneous ice nucleation potential of oxalic acid dihydrate and sodium oxalate

2010 ◽  
Vol 10 (16) ◽  
pp. 7617-7641 ◽  
Author(s):  
R. Wagner ◽  
O. Möhler ◽  
H. Saathoff ◽  
M. Schnaiter ◽  
T. Leisner
Keyword(s):  
Oxalic Acid ◽  
Acid Solution ◽  
Active Sites ◽  
Oxalic Acid Solution ◽  
Ice Nucleation ◽  
Sodium Oxalate ◽  
Supersaturated Solution ◽  
Oxalic Acid Dihydrate ◽  
Condensation Mode ◽  
Heterogeneous Ice Nucleation

Abstract. The heterogeneous ice nucleation potential of airborne oxalic acid dihydrate and sodium oxalate particles in the deposition and condensation mode has been investigated by controlled expansion cooling cycles in the AIDA aerosol and cloud chamber of the Karlsruhe Institute of Technology at temperatures between 244 and 228 K. Previous laboratory studies have highlighted the particular role of oxalic acid dihydrate as the only species amongst a variety of other investigated dicarboxylic acids to be capable of acting as a heterogeneous ice nucleus in both the deposition and immersion mode. We could confirm a high deposition mode ice activity for 0.03 to 0.8 μm sized oxalic acid dihydrate particles that were either formed by nucleation from a gaseous oxalic acid/air mixture or by rapid crystallisation of highly supersaturated aqueous oxalic acid solution droplets. The critical saturation ratio with respect to ice required for deposition nucleation was found to be less than 1.1 and the size-dependent ice-active fraction of the aerosol population was in the range from 0.1 to 22%. In contrast, oxalic acid dihydrate particles that had crystallised from less supersaturated solution droplets and had been allowed to slowly grow in a supersaturated environment from still unfrozen oxalic acid solution droplets over a time period of several hours were found to be much poorer heterogeneous ice nuclei. We speculate that under these conditions a crystal surface structure with less-active sites for the initiation of ice nucleation was generated. Such particles partially proved to be almost ice-inactive in both the deposition and condensation mode. At times, the heterogeneous ice nucleation ability of oxalic acid dihydrate significantly changed when the particles had been processed in preceding cloud droplet activation steps. Such behaviour was also observed for the second investigated species, namely sodium oxalate. Our experiments address the atmospheric scenario that coating layers of oxalic acid or its salts may be formed by physical and chemical processing on pre-existing particulates such as mineral dust and soot. Given the broad diversity of the observed heterogeneous ice nucleability of the oxalate species, it is not straightforward to predict whether an oxalate coating layer will improve or reduce the ice nucleation ability of the seed aerosol particles.

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