Linked Life Data

11541740

Source:http://linkedlifedata.com/resource/pubmed/id/11541740

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1999-5-29
pubmed:abstractText
Flow injection analysis instrumentation and methodology for the determination of ammonia and ammonium ions in an aqueous solution are described. Using in-line solid phase basification beds containing crystalline media. the speciation of ammoniacal nitrogen is shifted toward the un-ionized form. which diffuses in the gas phase across a hydrophobic microporous hollow fiber membrane into a pure-water-containing analytical stream. The two streams flow in a countercurrent configuration on opposite sides of the membrane. The neutral pH of the analytical stream promotes the formation of ammonium cations, which are detected using specific conductance. The methodology provides a lower limit of detection of 10 microgram/L and a dynamic concentration range spanning three orders of magnitude using a 315-microliters sample injection volume. Using immobilized urease to enzymatically promote the hydrolysis of urea to produce ammonia and carbon dioxide, the technique has been extended to the determination of urea.
pubmed:keyword
pubmed:language
eng
pubmed:citationSubset
S
pubmed:chemical
pubmed:status
MEDLINE
pubmed:author
pubmed:owner
NASA
pubmed:authorsComplete
Y
pubmed:pagination
372-82
pubmed:dateRevised
2007-7-17
pubmed:meshHeading
pubmed:articleTitle
"Reagentless" flow injection determination of ammonia and urea using membrane separation and solid phase basification.
pubmed:affiliation
UMPQUA Research Company, Myrtle Creek, Oregon 97457, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, Non-P.H.S.