Glossary



API stands for American Petroleum Institute, which represents all aspects of the U.S. petroleum and natural gas industry. In the oil industry, API Oil tables 53A, B and D of the API standard 2540 are used to determine the density of crude oils, oil products and lubricants at 15° C, resp. 60° F.


The "apparent density" is the density measured with pycnometers when weighed in air without reference to the buoyancy of air.
Apparent density is slightly different from the so called "true density", which is the density measured with pycnometers when weighed in vaccum or measured with a digital density meter.
More detailled information in Analytical Chemistry UserCom 4, page 11-13.

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Stands for American Society for Testing and Materials. Especially known for the various ASTM standards.


BATF stands for Bureau of Alcohol, Tobacco and Firearms. The BATF is a law enforcement organization within the United States Department of Treasury with unique responsibilities dedicated to reducing violent crime, collecting revenue, and protecting the public. BATF enforces the Federal laws and regulations relating to in the alcohol, tobacco, firearms, explosives and arson.


The degree Baumé was a hydrometer scale for density determinations. It originates from a french chemist Antoine Baumé (1728 - 1804). There existed up to 4 different Baumé scales, differing mainly in the measuring temperature. According to "Römpp Chemie-Lexikon" these Baumé scales are officially no longer allowed for the indication of densities of liquids.

The conversion formulas for the two most commonly used Baumé degrees can be found in the Operating Instruction of the DE40/50/51 in chapter 14.6. Measuring temperature for both is 15 °C, Heavy Baumé is used for densities that are higher thanone, while Light Baumé is used for densities lower than one.



Designation for the weight percent sucrose content of a sucrose/water solution (°BRIX). BRIX is generally used to determine the sugar content of a liquid, even if in most cases it doesn’t give the real sugar concentration: most of the measured liquids are not pure sucrose/water solutions (e.g. orange juice, tomato juice, milk). In these cases the BRIX values are only relative values, they do not specify the actual sucrose concentration.
BRIX values are generally measured by density (Saccharometer, Hydrometer, Pycnometer, Digital Density Meters) or by refractometry (Refractometers). Only whenmeasuring sucrose/water solutions both methods will give the same BRIX values. In all other cases (e.g. orange juice, tomato juice, milk) the BRIX values measured by density will be different from the BRIX values measured by refractometry. Example:
When measuring BRIX of orange juices with a refractometer, the measured value must be corrected according to an acidity correction table in order to give the real sugar content.
Density BRIX values are based on table 109 of NBS Circular 440. The measurement temperature for the automatic conversion is 20 °C.
Refractometer BRIX values are based ontabulated values of sucrose solutions (ICUMSA, T = 20°C).



FDA stands for Food and Drug Administration. FDA is the US department for health and human services.


HFCS stands for High Fructose Corn Syrup. This syrup is manufactured from natural corn syrup and consists of inverted (or isomerized) sugar, a mixture of dextrose, fructose, maltose and sucrose. They are classified according to their fructose content. Mainly three different HFCS are in use: a mixture containing 42% fructose (HFCS42), one containing 55% fructose (HFCS55) and a third one containing 90% fructose (HFCS90). Inverted sugar concentration denominates the concentration in weight % of an inverted sugar solution.


A hydrometer (also called aerometer) is a glass body used to measure the density of a liquid. This glass body is dipped into the sample. After a short equilibration time it will swim at a certain level (when the mass of the hydrometer is equal to the buoyancy effect). The higher the density of the sample, the less the hydrometer will sink. The level of equlibration reads the density on the calibrated scale.
Nowadays hydrometers are beeing replaced more and more with modern digital density meters.



ICUMSA (International Commission for Uniform Methods of Sugar Analysis) is a world-wide body which brings together the activities of the National Committees for Sugar Analysis in more than thirty member countries. Work is carried out under various Subject headings, each headed by a Referee. Methods are recommended for tentative approval by ICUMSA in the first instance. Upon meeting all of the Commission's requirements, methods are accorded official status. Methods which are demonstrably useful and have found an established application, or which do not lend themselves to collaborative testing are given an Accepted status" ).


NBS stands for National Bureau of Standards. Since 1988 has been replaced by NIST (National Institute of Standards and Technology).


NIST stands for National Institute of Standards and Technology. Since 1988 this is the new name of NBS (National Bureau of Standards).


OIML stands for “Organisation Internationale de Métrologie Légale”, which means International Organization of Legal Metrology. It was established in 1955 in order to promote the global harmonization of legal metrology procedures. Since that time, the OIML has developed a worldwide technical structure that provides its Members with metrological guidelines for the elaboration of national and regional requirements concerning the manufacture and use of measuring instruments for legal metrology applications.
OIML is an intergovernmental treaty organization whose membership includes Member States, countries which participate actively in technical activities, and Corresponding Members, countries which join the OIML as observers.



PTB stands for Physikalisch Technische Bundesanstalt. PTB is Germany's national metrology institute wich performs scientific and technical services.


A pycnometer is a glas beaker used to measure the density of a sample. This glass beaker has a defined volume. It is weighed without sample (M1), then filled with the sample and weighed again (M2). The difference between M1 and M2 (=Mass of the sample) divided by the volume of the beaker is the density of the sample.
Nowadays pycnometers are beeing replaced more and more with modern digital density meters.



SG stands for Specific Gravity. SG is a relative value, the density of a sample devided by the density of water (used as a reference) at the same temperature.

Example:
SG(ethanol) at 20°C = d(ethanol) at 20°C / d(water) at 20°C
SG(ethanol) = 0.78930 / 0.99821 = 0.79072
-> see " What is density? "



SOP stands for Standard Operating Procedure. The SOP's are usually written description of working steps, used to make sure that everybody uses exactly the same procedures, in the same sequence.
These SOP's can also be included in some instruments, in order to perform these sequences automatically (like the SOP's in our density meters).



The "true density" is the density of a sample without any influence of the buoyancy of air. True density is measured with digital density meters.
True density is slightly different from the so called "apparent density", which is the density measured with pycnometers when weighed in air without reference to the buoyancy of air. True density can be determined with a pycnometer, if measured in vaccum. As this is not really feasible, true density can be determined with a pycnometer by measuring apparent density and using a conversion formula.

At 20°C
True density = Apparent density * 0.99986 + 0.00120 g/cm3 .

More detailled information in our Usercom 4, page 11-13
-> see Glossary "Apparent density".