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Related to octane number: cetane number, Research octane number


1. See: Bond rating.

2. See: Credit score.


The grading of a security with respect to a characteristic or a set of characteristics such as safety and growth. Rating is most often applied to debt securities, which are graded according to the issuer's ability to pay interest and principal when due. See also bond rating, downgrading, Moody's Investment Grade, not rated, stock rating, upgrading.


Rating means evaluating a company, security, or investment product to determine how well it meets a specific set of objective criteria.

For example, a bond issue may be rated along a spectrum from highest quality investment grade to speculative, or from AAA to D.

Rating typically affects the interest rate a fixed-income security must pay to attract investors, forcing lower-rated bond issuers to pay higher rates. Other investors may shun low-rated investments entirely, unwilling to take the risk that the issuer might default. However, ratings are not infallible, even in industries, such as insurance, that are regularly scrutinized.

Rating differs from ranking, which assigns the relative standing of two or more similar items in relation to each other.

References in periodicals archive ?
Standard Test Method for Motor Octane Number of Spark-Ignition Engine Fuel," ASTM International.
In this regard, a matrix of E10 fuels with market relevant octane numbers and sensitivity values were tested in a single cylinder engine at various speed-load conditions and compression ratios to study the impact on engine efficiency or specific fuel consumption.
The analysis of information provided in Table 4 has revealed that evaporation changes fuel composition as well as its important physical and chemical characteristics, such as fractional composition, flash temperature, an octane number, density and the total content of aromatic hydrocarbons.
CO2 Emission Reduction Synergies of Advanced Engine Design and Fuel Octane Number," SAE Technical Paper 2014-01-2610, 2014, doi:10.
To tackle this situation, the Premium fuel is actually turned milder by increasing the octane number, so it is ignited only when the spark plug emits spark after efficient completion of every engine cycle.
Results indicated that 10% ethanol addition increases the engine power output by 5%, and the octane number can be increased by 5% for each 10% ethanol added.
The octane number of butanol is similar to petrol but is lower than that of ethanol and methanol.
For petrol the main parameters of concern were research octane number, summer vapour pressure and distillation-evaporation at 100[degrees]C.
For petrol, the main parameters of concern were research octane number, summer vapour pressure and distillation-evaporation at 100[degrees]C.
Natural gas has a high octane number, which raises the ceiling set by engine knock.
Consequently, many fuel formulations with diverse compositional details can maintain vital performance targets, such as Research Octane Number (RON) and Motor Octane Number (MON), within a narrow range as seen in FACE gasolines [3].