Specific index

With the accumulation of results obtained from various and complex analyses of narrow cuts (Waterman method), correlations have been found f ctween refractive index, specific gravity and molecular weight on one hand, and percentages of paraffinic, naphthenic and aromatic carbon on the other. 

When a customer agrees to purchase gas, product quality is specified in terms of the calorific value of the gas, measured by the Wobbe index (calorific value divided by density), the hydrocarbon dew point and the water dew point, and the fraction of other gases such as Nj, COj, HjS. The Wobbe index specification ensures that the gas the customer receives has a predictable calorific value and hence predictable burning characteristics. If the gas becomes lean, less energy is released, and if the gas becomes too rich there is a risk that the gas burners flame out . Water and hydrocarbon dew points (the pressure and temperature at which liquids start to drop out of the gas) are specified to ensure that over the range of temperature and pressure at which the gas is handled by the customer, no liquids will drop out (these could cause possible corrosion and/or hydrate formation). 

Component CAS Registry Number Mol wt Mp, °C Bp, Refractive index, Specific gravity, d Surface tension, 20°C mN/m (=dyn/cm) Flash point, °... 

Compound CAS Registry Number Molecular weight Melting point, °C Boiling point, °C" Refractive index Specific gravity Viscosity mPa(=cP) Solubihty in water at 25°C F poi... 

Physical Properties. Physical properties include specific gravity, water absorption, mold shrinkage, transmittance, ha2e, and refractive index. Specific gravity affects performance and has commercial implications. The price of the material divided by the specific gravity gives the yield in cost per unit volume. Comparison of yields gives an evaluation of raw material costs. 

Name Formula Formula weight Color, crystalline form and refractive index Specific gravity Melting point, C Boihng point, C Solubility in 100 parts ... 

Name Formula Formula weight Color, crystalline form and refractive index Specific gravity... 

Boiling point Specific gravity Refractive index Specific heat Heat of polymerisation... 

Specific rotation Refractive index Specific gravity... 

Specific gravity Refractive index. Specific rotation. ... 

Namen-gebung,/. naming nomenclature, -register, -verzeiclmis, n. name index, specif, author index list of names. 

DODISS. Department of Defense Index Specifications Standards. 

Check that errors of parameter estimation are within tolerance limits. Golden proposed an index that can be used to evaluate these errors. This index specifically focuses on errors that arise from the degrading effects of nuisance correlation and ignores sampling errors, as they cannot be minimized. 

One ingredient in pharmaceutical cough medicine preparations is a flavor oil. Pharmaceutical companies that produce such preparations purchase the flavor oil in bulk quantities and then perform a laboratory analysis on a sample of it to determine its quality. The method of choice for this is refractive index. The flavor oil raw material must be within the refractive index specification limits established for it before it can be used in the cough medicine production process. 

As a general rule, it is usually safe to assume that the calculated cetane index will always be higher than the actual cetane number. On rare occasions, the numbers will be the same, but usually not. Because of this, if a calculated cetane index value is known, it is reasonable to believe that the cetane engine number is usually one to two numbers lower than the calculated cetane index. For this reason, refiners often set cetane index specifications higher than the desired number by one to two numbers or more. 

Tg can be determined by studying the temperature dependence of a number of physical properties such as specific volume, refractive index, specific heat, etc. First-order transitions, such as the melting of crystals, give rise to an abrupt change or discontinuity in these properties. However, when a polymeric material undergoes a second-order transition, it is not the primary property (the volume), but its first derivative with respect to temperature, (the coefficient of expansion), which becomes discontinuous. This difference between a first and second-order transition is illustrated in Figure 10. 

It has not been possible, nor was it desirable, to index a compound or reaction at every mention in the text. Instead the essential features of compounds have been chosen, and individual compounds indexed specifically only where they are discussed in some detail. 

Substance Refractive Index Specific Volume, Cc. Molar Refraction, Cc. 

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