Search Results

You are looking at 1 - 10 of 939 items for :

  • Refine by Access: All Content x
Clear All

Introduction This work deals with two aspects of catalysis. The first one is the mechanism of hydrogen oxidation on silver. This reaction is essential for chemical kinetics and catalysis as a model catalytic redox reaction. It

Restricted access

Abstract  

A fast pneumatic transfer facility was installed in Nuclear Engineering Teaching Laboratory (NETL) of the University of Texas at Austin for the purpose of cyclic thermal and epithermal neutron activation analysis. In this study efforts were focused on the evaluation of cyclic epithermal neutron activation analysis (CENAA). Various NIST and CANMET certified materials were analyzed by the system. Experiment results showed 110Ag with its 25 s half-life as one of the isotopes favored by the system. Thus, the system was put into practical application in identifying silver in metallic ores. Comparison of sliver concentrations as determined by CENAA in CANMET certified reference materials gave very good results.

Restricted access

Abstract  

Large sample neutron activation analysis of dross from India Government Mint, Mumbai was carried out for quantification of gold (Au) and silver (Ag) using graphite reflector position of Advanced Heavy Water Reactor critical facility at Bhabha Atomic Research Centre, Mumbai. The k 0-based internal monostandard NAA was used to calculate concentration ratios of Au and Ag with respect to sodium (Na), which was used as an internal monostandard. The concentration ratio values of Au to Na of varying mass of dross showed that mass ≥2 g was the representative sample size for analysis. Concentrations of gold and silver were found to be in the range of 200–400 and 1200–1700 mg kg−1, respectively in three different samples.

Restricted access

Abstract  

Silver from aqueous solution was preconcentrated by adsorption on activated carbon as silver xanthate. Factors influencing the adsorption of silver have been studied. Optimum conditions for the preconcentration of silver have been established.

Restricted access

[ 16 ]. Raja et al. [ 17 ] reported increases of thermal and electrical conductivities of PU composites containing increasing amounts (1–5 wt%) of carbon nanotubes that were decorated with silver and copper nanoparticles but the main focus of this study

Restricted access

antibiotic resistance other alternative antimicrobial agents have gained increased attention in the past decades to prevent infections and silver compounds that belong to the most popular ones. Silver has been used as an important antimicrobial agent

Restricted access
Acta Alimentaria
Authors: J. Tangtua, C. Techapun, R. Pratanaphon, A. Kuntiya, V. Sanguanchaipaiwong, T. Chaiyaso, P. Hanmuangjai, P. Seesuriyachan, N. Leksawasdi, and N. Leksawasdi

. , YU , K.N. , KIM , J.H. , P ARK , S.J. , LEE , H.J. , KIM , S.H. , P ARK , Y.K. , P ARK , Y.H. , H WANG , C.Y. , KIM , Y.K. , LEE , Y.S. , J EONG , D.H. & C HO , M.H. ( 2007 ): Antimicrobial effects of silver nanoparticles

Restricted access

The thermal decompositions of the even silver dicarboxylates from silver oxalate to silver sebacate were studied. In vacuum, the dicarboxylates decomposed to give metallic silver, CO2 and organic diradicals as primary products, and polymers as secondary products. The higher silver dicarboxylates were much more stable to thermal treatment than silver oxalate, probably due to the initiation of decomposition of all carboxylates except silver oxalate by the rupture of a Ag-O and not a C-C bond.

Restricted access
Journal of Thermal Analysis and Calorimetry
Authors: L. Chmielarz, M. Zbroja, P. Kuśtrowski, B. Dudek, A. Rafalska-Łasocha, and R. Dziembaj

Abstract  

Alumina, zirconia and titania pillared montmorillonites additionally modified with silver were tested as catalysts of NO reduction with NH3 or C2H4. Ammonia was much more effective reducer of NO than ethylene. The silver containing TiO2-pillared clay has been found to be the most active catalyst for NO reduction both with NH3 or C2H4. Oxidation of the reducing agents by oxygen limited the NO conversion in the high temperature region. The ammonia and nitric oxide adsorption sites were studied by the temperature programmed desorption methods (TPD).

Restricted access

Conflicting results have been reported by different workers on the thermal decomposition of silver carbonate, Ag2CO3. In the present study, the decomposition mechanism was elucidated by various analytical methods; gas analysis (differential thermal gas analyses) in helium, carbon dioxide and oxygen flows with and without a P2O5 trap or a KOH trap, DTA-TG in a carbon dioxide flow and high-temperature X-ray diffraction analysis in a carbon dioxide flow.

Restricted access