Determination oxidation

Comparison of specific surface of anatase and zinc oxide determined by electron microscopy A ) and by nitrogen adsorption A )... 

A systematic study632 in which substituted thiiranes were oxidized to the corresponding thiirane oxides determined the geometrical position of the oxygen atom by complete NMR and microwave analysis. 

Identification of sources of analytical bias in method development and method validation is another very important application of reference materials in geochemical laboratories. USGS applied simplex optimization in establishing the best measurement conditions when the ICP-AES method was introduced as a substitute for AAS in the rapid rock procedure for major oxide determinations (Leary et al. 1982). The optimized measurement parameters were then validated by analyzing a number of USGS rock reference samples for which reference values had been established first by classical analyses. Similar optimization of an ICP-AES procedure for a number of trace elements was validated by the analysis of U S G S manganese nodule P-i (Montaser et al. 1984). 

Figure 1 The theoretical plot of induction time of oxidation determined for wr — 0, (zero rate of initiation according to reaction 1 of Scheme 1) on composition of the mixture of inhibitors InH (chain-breaking antioxidant) and D (peroxide decomposer) having the total sum of concentrations 0.01 mol/l. The curve 2 below is the plot of induction times for the same values of parameters as for line 1 but w, = 5 x 10-8 mol/l. The initial concentration of hydroperoxides was 0.001 mol/l.

Electrochemical Sensors for Nitrite and Nitric Oxide Determination 492... 

J. Katrlik and P. Zalesakova, Nitric oxide determination by amperometric carbon fiber microelectrode. Bioelectrochemistry 56, 73-76 (2002). 

Epp MA, Chanton JP. 1993. Rhizospheric methane oxidation determined via the methyl-fluoride inhibition technique. Journal of Geophysical Research-Atmospheres 98 18413-18422. 

Infrared data in the 1575-400 cm region (1218 points/spec-trum) from LTAs from 50 coals (large data set) were used as input data to both PLS and PCR routines. This is the same spe- tral region used in the classical least-squares analysis of the small data set. Calibrations were developed for the eight ASTM ash fusion temperatures and the four major ash elements as oxides (determined by ICP-AES). The program uses PLSl models, in which only one variable at a time is modeled. Cross-validation was used to select the optimum number of factors in the model. In this technique, a subset of the data (in this case five spectra) is omitted from the calibration, but predictions are made for it. The sum-of-squares residuals are computed from those samples left out. A new subset is then omitted, the first set is included in the new calibration, and additional residual errors are tallied. This process is repeated until predictions have been made and the errors summed for all 50 samples (in this case, 10 calibrations are made). This entire set of... 

Hollingsworth RL et al Toxicity of ethylene oxide determined on experimental animals. AMA Arch Ind Health 13-2 1- 1, 1956... 

The common oxide of aluminum provides a second example, but this time, begin with the weight percent and deduce the atomic ratio. Careful laboratory analysis of aluminum oxide determines it to be approximately 53% aluminum and 47% oxygen by weight, as shown in the second column in Table 2-3. 

According to the presented model of oxides formation on Au, the outer surface of the thick oxide film exposed to the solution is either AU2O3 or Au(OH)3. The type of oxide determines the surface electronic structure and electrocatalytic properties. Electrocatalytic properties of gold oxide-covered electrodes have been discussed by Burke and Nugent [366, 368]. 

N = normality of the NaOH soln Retest. Retest the lot if the results of tests of the composite and the individoal samples vary over a range greater than 0.335 Water. Determine the water content of a 50-ml specimen of the EtnO as specified in ASTM Standard D1364. Calculate the weight of the specimen tested using the specific gravity of the ethylene oxide determined by means of a suitable hydrometer... 

TABLE 2. Critical Micelle Concentration of Polyjethylene oxide-/>-[(R)-3-hydroxybutyrateJ diol-ft-ethylene oxide Determined at 23°C in Aqueous Solution... 

The reduction of transition metal oxides and of Sn02 + Sb2Os by 1-butene and butadiene were investigated. A single parameter defined as the heat necessary to dissociate 1/2 02 from the oxide, determined the type of reaction. Starting from Q0 = 17 (MnOz) and proceeding to Q0 = 70 (Sn02), the reduction produces ... 

In atomic spectroscopy, absorption, emission, or fluorescence from gaseous atoms is measured. Liquids may be atomized by a plasma, a furnace, or a flame. Flame temperatures are usually in the range 2 300-3 400 K. The choice of fuel and oxidant determines the temperature of the flame and affects the extent of spectral, chemical, or ionization interference that will be encountered. Temperature instability affects atomization in atomic absorption and has an even larger effect on atomic emission, because the excited-state popula-... 

Hardness of sintered aluminium oxide determined by dynamic abrasion with SiC grain, (after A. Szymaiiski, 1974)... 

The rearrangement of light and deuterium-labelled cis- and trans-2-methyl-3-phenyloxiranes (1, 2 and 1, 2 ) was studied on ZnO, Al-O-j and WO, and in the presence of BF,. Both in the gas phase (473-673 K) and in the liquid phase (298-413 K), l-phenyl-2-propanone (3) and 2-phenylpropanal (4) were formed with high selectivities (0-90% and 11-80%, respectively). Ring-opening was found to occur by selective fission of the benzyl C-0 bond. Mechanistic studies revealed the formation of an open carbenium ion or a double-bonded surface intermediate. The acidic (electrophilic) and basic characters of the oxides determine the product distributions by affecting the relative importance of the competing mechanisms. 

The use of a tubular carbon electrode (TCE) for the electrochemical oxidative determination of ascorbic acid [159], L-dopa [160], and methyldopa [161] in dosage forms has been described. The flow system, electrode assembly, and electrochemical instrumentation required for these assays are shown in Figure 26.11. The method is based on continuous analysis in flowing streams... 

Experimental method. In the flask P (see Fig. 1) a mixture was made up at an initial pressure of 200 mm and a temperature of 20° C. Then an electric heater was fitted on to the flask which was heated together with the explosive mixture in it. We estimated the temperature of the mixture by the change in pressure. After a steady temperature was reached (varying in different experiments between 200-300° C) the mixture was exploded. The heater was then removed and the nitric oxides determined as in 3. It was shown by special experiments that even after the flask had been in the heater for fifteen minutes there was no loss of nitric oxide after the explosion. In some experiments the mixture was cooled before the explosion, the flask P being wrapped in a cloth and abundantly wetted with liquid nitrogen. 

Heterogeneous electron transfer rate constant, see equation (8) in text, for i oxidation determined as in ref. 16. dData from ref. 16. 

The properties, crystal habit, and x-ray pattern of tungsten(IV) dichloride oxide are very similar to those of molybdenum(IV) dichloride oxide.8 Stoichiometric tungsten(IV) dichloride oxide, which forms gold-brown needles, is stable under atmospheric conditions and is not attacked by water, dilute or concentrated cold acids, ammonia, or organic solvents, such as acetone, ethanol, 2-methoxyethanol, chloroform, and diethyl ether. However, it decomposes in a solution of sodium hydroxide and forms a black precipitate, which disappears when hydrogen peroxide is added and yields a clear, yellow solution. The density of tungsten(IV) dichloride oxide, determined pycnometrically as previously mentioned, is 5.92 g./cc. 

Shutenko Z, Henry Y, Pinard E, Seylaz J, Potier P, Berthet F. 1999. Influence of the antioxidant quercetin in vivo on the level of nitric oxide determined by electron paramagnetic resonance in rat brain during global ischemia and reperfusion. Biochem Pharmacol 57 199-208. 

Hashimoto T, Cook WS, Qi C, Yeldandi AV, Reddy JK, Rao MS. Defect in peroxisome proliferator-activated receptor alpha-inducible fatty acid oxidation determines the severity of hepatic steatosis in response to fasting. J Biol Chem 2000 275 28918-28928. 

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