Glossary

Filter technology similar to reverse osmosis that is capable of filtering colloids and large molecular weight organics out of the water. The filter capability of ultrafiltration filters to 0.005 µm particle size. Ultrafiltration also will remove organic material down to about 1,000 10, 000 molecular weight.

Filtration under pressure similar to Reverse Osmosis. It consists of molecular sieves; membranes with pores small enough to remove colloids and large molecules. Rated in terms of nominal molecular weight cutoff. A 10,000 Dalton (molecular weight) UF membrane, for example, will remove bacterial pyrogens that are typically in the range of 20,000 Daltons.

Filter technology similar to reverse osmosis that is capable of filtering colloids and large molecular weight organics out of the water. The filter capability of ultrafiltration filters to 0.005 µm particle size. Ultrafiltration also will remove organic material down to about 1,000 10, 000 molecular weight.

Particle with an equivalent diameter less than 0,1µm. ISO 14644-1, ISO 14644-3.

Water with a specific resistance higher than 1 megohm-cm. In the laboratory, it usually refers to Type I reagent grade water. Anything in laboratory water that is not H2O is an impurity. Although chemically pure water is not attainable, ultrapure water systems are now capable of reducing impurities down to the limits of detection.

A method for detecting imperfections in materials by passing ultrasonic vibrations (frequencies normally 1 MHz to 5 MHz) through the material.

A unit operation through which water flows while exposing it to specific wavelengths and doses of ultraviolet light depending on its use in a high purity water system. The uses include microbial control, Total Organic Carbon (TOC) reduction, Chlorine/Chloramine reduction, and Ozone destruction applications.

The portion of the electromagnetic spectrum with wavelengths from about 100 to 400 nm; between ionizing radiation (X-rays) and visible light. UV is absorbed by DNA and is highly mutagenic to unicellular organisms and to the epidermal cells of multicellular organisms. UV light is used in tissue culture for its mutagenic and bactericidal properties.

Ultraviolet radiation is employed in water purification for the photochemical oxidation of organic impurities resulting in HPLC grade water with organic impurity levels below 0.0005 absorbance units.

A UV source, which partially oxidizes organic compounds to ionic species that can be removed. Relies on 185 nm (nanometer) radiation from “ozone producing” mercury lamps (along with 254nm germicidal radiation). Generally has a longer contact time than sterilization alone.

Leakage level above which the system performance is considered unacceptable by the system user and applicable regulating body.

Not susceptible to different interpretations.

Not having two or more possible meanings.

Not obscure, not vague.

Clear, definite, certain.

In addition to drug and intervention associated adverse events, other types of unexpected/unanticipated adverse events (unanticipated problems) might be associated with subjects' participation in research studies. An unanticipated problem resulting in risk to subjects or others requires reporting to the Committee. Examples of unanticipated problems are serious psychological and/or emotional distress, compromised confidentiality, and negative social, legal or economic consequences.

Unified National Coarse

Support area peripheral to manufacturing, (e.g., warehouse, office).

A medium or substance added to medium in which not all of the constituents or their concentrations are chemically defined, such as media containing coconut milk, malt extract, casein hydrolysate, fish emulsion or other complex compounds.

An uncommon method of biomolecular preservation in which emulsions are used to cool the solution below its freezing point without freezing.

A groove melted into the base metal adjacent to the weld toe or weld root and left unfilled by weld metal.

A depression on the weld face or root surface extending below the adjacent surface of the base metal.

(ISO) The state in which a calculator shows a zero indicator for the most significant part of a number while the least significant part of the number is dropped. For example, if the calculator output capacity is four digits, the number .0000432 will be shown as .0000.

The dewatered solid that result from compaction during centrifugation.

(IEEE) An exception that occurs when the result of an arithmetic operation is too small a fraction to be represented by the storage location designated to receive it.