Carbon-14 method

Reference methods for criteria (19) and hazardous (20) poUutants estabHshed by the US EPA include sulfur dioxide [7446-09-5] by the West-Gaeke method carbon monoxide [630-08-0] by nondispersive infrared analysis ozone [10028-15-6] and nitrogen dioxide [10102-44-0] by chemiluminescence (qv) and hydrocarbons by gas chromatography coupled with flame-ionization detection. Gas chromatography coupled with a suitable detector can also be used to measure ambient concentrations of vinyl chloride monomer [75-01-4], halogenated hydrocarbons and aromatics, and polyacrylonitrile [25014-41-9] (21-22) (see Chromatography Trace and residue analysis). 

Daley, M. A., Tandon, D., Economy, J. and Hippo, E. J., Elucidating the porous structure of activated carbon fibers using direct and indirect methods. Carbon, 1996,34(10), 1191 1200. 

Tanahashi, I., Yoshida, A. and Nishino, A., Characterization of activated carbon fiber cloths for electric double layer capacitors by adsorption method. Carbon, 1991, 29(7), 1033 1037. 

In this study we have shown that the catalytic method—carbon deposition during hydrocarbons conversion—can be widely used for nanotubule production methods. By variation of the catalysts and reaction conditions it is possible to optimize the process towards the preferred formation of hollow... 

Calas-Blanchard C., Comtat M., Marty J.-L., Mauran S. Textural characterisation of graphite matrices using electrolchemical methods. Carbon 2003 41 123-130. 

Applications of quantum mechanical methods Carbon nitride... 

Sample No. Carbon content % Proposed method Dry[Pg.320]

For the arc method, carbon or iron electrodes are used. In the spark method, the " simple spark , Feussner spark, Hasler spark and Wolfe spark are used... 

Calcium was determined by an EDTA method carbon and hydrogen by the combustion method total nitrogen by the Kjeldahl method sulfur by the Eschka method infrared spectra by the potassium bromide pellet technique. 

Siaff Rubber, Natural and Synthetic-General Test Methods, Carbon Black. American... 

Carbon dioxide miscible recovery is a preferred method. Carbon dioxide may not be initially misdble with crude oil, but when it is forced into an oil reservoir, some of the smaller, lighter hydrocarbon molecules in... 

Ceramic fibers used in composites are usually made by high-temperature methods. Carbon (graphite) fiber, for example, can be made by the thermal decomposition of fibers of polyacrylonitrile, a long-chain organic molecule also used to make the textile Orion ... 

Diaryliodonium Salts Preparative Methods. Carbon-Carbon Bond-Forming Reactions. Arylation of Heteroatoms. 

Lopez P.N., Ramos I.R., Ruiz A.G. A study of carbon nanotube formation by C2H2 decomposition on an iron based catalyst using a pulsed method. Carbon, 2003,41(13), 2509-2517. 

All products were washed thoroughly and dried at ca. 105°C overnight. Product identities and phase purities were determined by powder XRD. Silicon and aluminum were determined by wet chemical methods, carbon and hydrogen were determined by a combustion process, and sodium was determined by atomic absorption spectroscopy. Framework Si/Al ratios were determined by established XRD correlations for Y(ll) and ZK-4(12) some ratios were also determined by Si R. TMA, in total and in specific locations, was determined by C NMR(8). 

A number of terms are used for the thermal decomposition of wood and generally refer to similar processing methods carbonization, pyrolysis, gasification, wood distillation, destructive distillation, and dry distillation. All result in the thermal breakdown of the wood polymers to smaller molecules in quantities dependent on reaction conditions. The hydrogen content of the gas increases with increasing temperature of pyrolysis. The wood gas has a fuel value of 300 BTU/ft3. 

Supercritical carbon dioxide is a good solvent for a variety of substances. Due to low temperatures and pressures being necessary to achieve supercritical conditions, production techniques work under relatively mild conditions III. Another important feature of supercritical carbon dioxide is the gaslike viscosity causing favourable transport porperties, so that for example supercitical fluid extractions (SFE) are achieved faster than with traditional methods. Carbon dioxide is intoxic and so incurs less costs for disposal than conventional organic solvents 111. 

In the last 10 years, as a result of more efficient operating methods, carbonate stress corrosion cracking has occurred in the fractionator overheads in fluid catalytic crackers. The problem is most severe at a pH greater than 9 and a carbonate concentration above 110 ppm. It has also occurred at a pH between 8 and 9 when the carbonate concentration is above 400 ppm. Therefore, most refiners are now specifying postweld heat treatment of carbon steel when such conditions are anticipated. 

Du, F., et al. (2006), The synthesis of single-walled carbon nanotubes with controlled length and bundle size using the electric arc method, Carbon, 44(7), 1327-1330. 

Lian, Y. R, Shi, Z.J., Zhou, X.H. etal. (2000) High-yield preparation of endohedral metallofullerenes by an improved DC arc-discharge method. Carbon, 38, 2117-2121. 

Z. Ryu, H. Rong, J. eng, M. Wang, and B. Zhang, Microstructure and chemical analysis of PAN-based activated carbon fibers prepared by different activation methods. Carbon 40 (2002) pp. 1144-1147. 

Analytical Methods. Carbon, hydrogen, nitrogen, and sulfur analyses and Hempel distillations (IS) were performed using conventional analytical techniques. Nickel and vanadium contents were determined by the methods of Bean (14). These methods involve the colorimetric determination of nickel dimethylglyoxime and tungstovanadic acid, respectively. Simulated distillations were done by the method of Poulson... 

Kitamura et al. proposed three different ways to manage the pressure profile (78). In the stepwise method, carbon dioxide was added gradually in 5-bar increments until the maximum pressure was reached. In the rapid pressurization method the maximum pressure was reached as rapidly as possible. Finally the so-called two-step pressurization involved an initial increase in pressure as rapidly as possible, followed by reduction to a decompression point to control the crystal growth this second step is... 

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