C

CAFE

Corporate Average Fuel Economy

Calorie

1. The amount of heat required to raise the

temperature of 1 g of water 1°C, at or near the

temperature of maximum density. This unit is

called a “small calorie”, or “gram calorie”.

2. The amount of heat required to raise the

temperature of 1 kg of water 1°C. This unit is

called a “large calorie” or “kilogram-calorie”.

Capillary Viscometer

A viscometer in which the oil flows through a

capillary tube.

CARB

California Air Resources Board

CCMC

Comite des Constructeurs d’Automobile du

Marche Commun (Common Market Automobile

Manufacturers Association)

CEC

Coordinating European Council

Centistoke (cSt)

The worldwide unit of kinematic viscosity. (See

inside cover for Viscosity Grade Comparisons

Chart)

Cetane Number (calculated)

The cetane number of distillate fuels as

estimated from the API gravity and mid-boiling

point by using a formula given in Appendix II of

ASTM Method D 975. This estimate is used if

a standard test engine is not available, or if the

sample is too small for an engine test.

Cetane Number (test method)

The percentage by volume of normal cetane, in

a blend with heptamethylnonae (HMN), which

matches the ignition quality of the fuel when

compared by the procedure specified in ASTM

Method D 613.

Cetane Number Improver

A substance which, when added to a diesel fuel,

has the effect of increasing its cetane number.

In this class are nitro alkanes, nitrates, nitro

carbonates and peroxides.

Cetane Index

An approximation of cetane number based on

API gravity and mid-boiling point of fuel.

CFR

Coordinating Fuel and Equipment Research

Committee, composed of engine-manufacturers,

petroleum-refiners, petroleum-consumers,

universities, government and other technical

people who supervise cooperative testing and

study engine fuels for the Coordinating Research

Council, Inc.

Channeling

1. The phenomenon observed among gear

lubricants and greases when they thicken, due

to cold weather or other causes, to such an

extent that a groove is formed through which

the part to be lubricated moves without actually

coming in full contact with the lubricant.

2. A term used in percolation filtration; may be

defined as a preponderance of flow through

certain portions of the clay bed.

Chromatography

A method of separation based on selective

absorption. A solution of the substance is

allowed to flow slowly through a column of

absorbent. Different substances will pass with

different speeds down the column and will

eventually be separated into zones. The column

core can then be pushed out and the zones of

material cut apart, or the zones can be eluted

by passing more solvent down the column and

collecting it in small fractions.

Partition Chromatography involves the

selective solution of the desired material

between two solvents. The final solvent,

usually water, is used to wet the solid material

packed in the column, and the first solvent

containing the desired material is poured into

the column as described.

Paper Chromatography is a micromethod.

A drop of the liquid to be investigated is placed

near one end of a strip of paper. This end is

immersed in solvent which travels down the

paper and distributes the materials present

in the original drop selectively. Comparison

with known substances makes identification

possible.

Gas Chromatography is an analytical

technique for separating mixtures of volatile

substances. The procedure consists of

introducing the mixture to be examined into the

chromatographic column and washing it down

(eluting it) with an inert gas. The column is

packed with adsorbent materials which

selectively retard the components of the sample.