Equivalent carbons

Ecample Suzuki et. al. used a reaction strategy to expand the Cgo molecule, buckminsterfullerene, by adding divalent carbon equivalents. Adding phenyl diazomethane to Cgo. (I)> followed by the loss of molecular nitrogen, results in a Cgi compound. 

FIA). Figure 25-39 presents a schematic of the sampling system. Results are reported as volume concentration equivalents of the cah-bration gas or as carbon equivalents. 

The carbon equivalent for the maximum composition figures given is... 

Poor Weldability a. Underbead cracking, high hardness in heat-affected zone. b. Sensitization of nonstabilized austenitic stainless steels. a. Any welded structure. b. Same a. Steel with high carbon equivalents (3), sufficiently high alloy contents. b. Nonstabilized austenitic steels are subject to sensitization. a. High carbon equivalents (3), alloy contents, segregations of carbon and alloys. b. Precipitation of chromium carbides in grain boundaries and depletion of Cr in adjacent areas. a. Use steels with acceptable carbon equivalents (3) preheat and postheat when necessary stress relieve the unit b. Use stabilized austenitic or ELC stainless steels. 

Carbon Equivalent (CE) is an approximate measure of weldability expressed in terms of the sum of carbon content and the alloy contents divided by applicable factors to relate equivalence in carbon in effectiveness in hardening—and thereby cracking. Commonly used formulas with commonly accepted but rather arbitrarily set maximums are ... 

Steel may have some merit SSCC of weld repairs in well-head alloys was investigated by Watkins and Rosenberg who found that the repairs were susceptible to this problem because of the hard HAZs developed by welding. Post-weld heat treatment was an essential but not complete cure compared with unrepaired castings. In the case of hydrogen-assisted cracking of welded structural steels, composition is more important than mechanical properties and the carbon equivalent should be... 

Types 304 and 316 and their low carbon equivalents (L) are commonly used as construction materials. 

Loss on carbon (equivalent decolorization use to bone char) 0.08%... 

Turning to the substrate balance, yeast cells contain about 50% carbon. The cell mass is measured as total dry weight, not just carbon. This gives Yx/s = 2 when S is measured as the carbon equivalent of glucose. A reasonable value for Yxis is 1 so that half the carbon goes into biomass and half meets the associated energy requirements. The maintenance coefficient in carbon-equivalent units is 0.008 h . Using these parameter estimates, the three simultaneous ODEs for 5" > 0, become... 

Each greenhouse gas differs in its ability to absorb heat in the atmosphere. HFCs and PFCs are the most heat-absorbent. Methane traps over 21 times more heat per molecule than carbon dioxide, and nitrous oxide absorbs 270 times more heat per molecule than carbon dioxide. Often, estimates of greenhouse gas emissions are presented in units of millions of metric tons of carbon equivalents (MMTCE), which weighs each gas by its GWP value, that is, Global Warming Potential. 

Biomass residues from agriculture cultivation and harvesting 4.6 GT/y (Carbon equivalents)... 

Global chemical Induatry 0.664 GT/y oil equivalents 0.569 GT/y carbon equivalent... 

Sulfapyridine, 281 Sulfinpyrazone, 282 Sulfisoxazole, 284 Sulfobetaine surfhctants, 298 Sulfonamides, 281,297. tlimiridin, 797 Sunset Yellow, 249 Superficial velMity, 167 Surfime area, molar, 171 Sur UK carbon equivalent, 142 Surface coverage, 144 Surftce modification, 59 Suifsce properties, 125 Surhwe tension, 163, 166, 169,217 correction (isctor for. 203, 213 Sur ctant chromatography, 242... 

Fig. 2. World per capita carbon dioxide emissions (expressed as carbon equivalent) from the consumption and flaring of fossil fuels for the year 2001. Thick vertical line represents global average FSU = Former Soviet Union. Data from EIA (2003).

Calcium carbonate is used to buffer acidic soils. In soils that contain sulfuric acid calcium carbonate, it will react with the acid to produce calcium sulfate (CaS04), carbon dioxide, and water H SO., + CaCO.M —> CaSO., + CCU + H.O... The ability ofvari-ous limes to neutralize acid in a soil is given in terms of calcium carbonate equivalents. In this system, limestone has a calcium carbonate equivalent of 100. If a slaked lime (calcium hydroxide) has a calcium carbonate equivalent of 150, then only two-thirds as much of slaked lime would be needed to achieve the same neutralizing effect. Calcium carbonate... 

Ultraviolet absorption is particularly useful for the determination of compounds possessing conjugated unsaturation and as far as hydrocarbon gases are concerned, this includes diolefins such as 1,3-butadiene and its five carbon equivalents. 

Table 4.15. Methane emissions from different sources recalculated for carbon equivalent. From EPA (2001). Estimates of methane fluxes are given in 106 tC per year.

Figure 1.11, prepared by the U.S. Energy Information Administration, describes the global carbon cycle. It provides data that was collected in 2001. Since that date, the yearly anthropogenic carbon emissions (measured in carbon equivalent terms) increased from 6.3 to about 9 billion metric tons (over 1 ton per capita in the world). In November 2007, the National Academy of Science reported actual emissions for 2006 as 8.4 billion tons. Carbon equivalent means that the emission of 3.7 tons of COz is counted as the emission of 1 ton of carbon, so the 8.4 billion tons per year of carbon that enters the atmosphere owing to fossil fuel combustion corresponds to 33 billion tons per year of C02 because of the molecular weight ratio of COz to carbon (44/12). 

The anthropogenic greenhouse gas emissions in 2001 in the United States in million metric tons of carbon equivalent. (From Energy Information Administration.)... 

Figure 5. Increase in Carbon Equivalency Versus Solution Time for Various Carbon Raisers.

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