Weight percentage

Plant-fiber identification is described in TAPPI T8 and TIO. In order to identify synthetic fibers, it usually is necessary to conduct solubihty and physical properties tests in addition to light microscopy observations. Systematic sampling is required to obtain quantitative information on sample composition. Because different types of pulps contain varying numbers of fibers per unit weight, it is necessary to multiply the total number of each kind of fiber by a relative weight factor, thereby the weight percentage that each fiber type contributes to the sample can be deterrnined. 

Fig. 3. Graph based on an hplc chromatogram of a commercial PTMEG of molecular weight = 1000. The bars represent the weight percentage of the individual oligomer fractions. The degree of polymerization is the number of repeating monomer units per polymer chain.

Although the mbbery properties of ethylene—propylene copolymers are exhibited over a broad range of compositions, weight percentages of commercial products generally range from 50 50 to 75 25 ethylene propylene. 

Coal analyses are reported on severalbases, and it is customaiy to select the basis best suited to the application. The as-received basis represents the weight percentage of each constituent in the sample as received in the laboratoiy. The sample itself may be coal as fired, as mined, or as prepared for a particular use. The moisture-free (diy) basis is generally the most useful basis because performance calculations can be easily corrected for the ac tual moisture content at the point of use. The dry, ash-free basis is frequently used to approximate... 

The oxides in parentheses are the weight percentages of these oxides when Si02 + AI2O3 -t- Fe203 -t- CaO -t- MgO = 100. 

Another useful element in imparting oxidation resistance to steel is silicon (complementing the effects of chromium). In the lower-chromium ranges, silicon in the amounts of 0.75 to 2 percent is more effective than chromium on a weight-percentage basis. The influence of 1 percent silicon in improving the oxidation rate of steels with varying chromium contents is shown in Fig. 28-26. 

An example where one metal melts before the densihcation process, is the formation of bronze from a 90 10 weight percentage mixture of copper and tin. The tin melts at a temperature of 505 K, and the liquid immediately wets the copper particles, leaving voids in the compact. The tin then diffuses into the copper particles, leaving further voids due to dre Kirkendall effect. The compact is therefore seen to swell before the hnal sintering temperature of 1080 K is reached. After a period of homogenization dictated by tire criterion above, the alloy shrinks on cooling to leave a net dilatation on alloy formation of about 1%. 

Certain thermodynamic relations exist between the state variables. In general for a binary alloy we choose p, T and Xg (the at% of component B) as the independent variables - though presently we shall drop p. The volume 1/ and the composition Xa (= 1 - Xg) are then determined they are the dependent variables. Of course, the weight percentages Wa and Wg can be used instead. 

Arrestance, average The weighted percentage ratio of the total amount of standardized test dust retained by a filter to the total amount of dust fed into the filter in order to achieve a specified final pressure drop. 

Five to 10 c.c. of the oil are shaken in a Hirschsohn fiask, as used for cassia oil analysis, with a 5 per cent, solution of caustic soda, until absorption is complete, and the unabsorbed oil driven into the neck cf the flask by more of the solution and its volume read off. The difference between the original amount of oil used and the unabsorbed portion may be taken as phenols. Strictly speaking, this method gives a volume percentage, which can be converted into a weight percentage if the specific gravities of the two portions of the oil be known. 

One important measurement made by geochemists is the Total Organic Carbon (TOC) measurement. The results are expressed as a weight percentage. When the TOC is less than 0.5 percent, the rock is considered unlikely to have enough kerogen to produce oil or gas. 

A detailed breakdown is given in Table II of the Spec for the min max weight percentages allowable for retention on and passage thru specific sieves... 

The viscosity of alcohol sulfate and alcohol ether sulfate solutions is sensitive to the amount of byproducts contained in the solution. Putnik and McGuire [76] developed an empirical equation [Eq. (10)] relating the kinematic viscosity of a sodium C12-C16 alcohol sulfate to the weight percentages of free oil (FO), sulfate ion (S04), and chloride ion (Cl) ... 

Throughput 85% weight percentage of nominal for alkylbenzene (this corresponds with about 50-70% on a mole basis—less heat of reaction-lower temperature peak)... 

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