Filter HNO3 collection

Nylon after-filter Collect HNO3 Collection of volatilized PN retention of HONO retention of unidentified species yielding N03"... 

Water samples were collected in midsummer, precipitation-free periods, following protocols of Ficklin Mosier (1999). On-site measurements include pH, specific conductance, alkalinity, acidity, dissolved oxygen, turbidity, and water temperature. Samples were collected in 1-litre polypropylene bottles and filtered onsite (0.45 pm) with disposable filters. Subsamples for cation analysis were placed in acid-rinsed polypropylene bottles and acidified with ultra-pure HNO3. Filtered, unacidified sub-samples for anion analysis were refrigerated until analyzed. In 2007, samples for Hg analysis were collected no Hg was detected at detection limits of 0.02 pg/L, precluding collection in 2008. 

Data Treatment. The experimental design of sample collection did not permit statistical comparison of the collection efficiencies of filter combinations versus concentrated HNO3 impingement. The laboratory chamber was designed to simulate field conditions and not provide a "closed" system in which the concentrations of Plictran could be controlled. 

PTFE prefilter Collect FPN and other particles and transmit HN03 to collection filter Partial retention of HNO3 on particles (enhanced if coarse particles are collected) volatilization or reaction of FPN yielding HN03... 

Air (total chromium) Air particulate collected on cellulose ester filter, wet wash with HCI/HNO3 Flame atomic absorption 0.06 pg/sample 98% at 45-90 pg/sample NIOSH 1994c (Method 7024)... 

Collection of metal complexes of the analytes on suitable adsorbing materials is often employed as an enrichment step in combination with flame methods. In a procedure proposed by Solyak et al. [20], five metals [Co(II), Cu(II), Cr(III), Fe(III), and Pb(II)] were complexed with calmagite 3-hydroxy-4-[(6-hydroxy-m-tolyl)azo]-naphthalenesulfonic acid and subsequently collected on a soluble cellulose nitrate membrane filter. In this way an effective separation from alkaline and alkaline earth metals was achieved, based on the differences in their complex formation constants and those of the transition elements. The experimental parameters were optimized for the quantitative recovery of the elements. After hot dissolution of the filter with HNO3, the analytes were determined by FAAS. Minimum detectable concentrations ranged from 0.06 pg l-1 for Cu to 2.5 pg l-1 for Cr. 

Air Air particulate collection on glass fiber filter digestion in HNO3 ICP-MS (total uranium) 0.1 pg/L in final solution No data Boomer and Powell 1987... 

J,m pore-size capsule filter. Samples analyzed for cations were acidified to a pH of about two in the field with ultra pure HNO3. Samples for analysis of nitrogen species and phosphate were collected in opaque plastic bottles and chilled to about 3 °C. Urrfiltered samples also were collected, primarily for analysis of arsenic and iron. 

Elements constituting the residue 5 mL of 5 M HF 1 M HCl + 0.5 M HNO3 solution was added to the residue of the previous treatment, and this was heated to 95 °C in a hot bath to dry. This treatment was repeated till the disappearance of any trace of residue. The residue was then recovered with 40 mL of 0.5 M HNO3 solution and left overnight. The mixture was centrifuged and the supernatant filtered, collected and stored at 2°C. 

Air filters and gummed deposition collection films first are measured by gross alpha- and beta-particle counting and gamma-ray spectral analysis. Usually, 1/2 of the sample then is dissolved to perform radiochemical analysis of the deposited radionuclides. The filter can be dry ashed, and then totally dissolved with an HNO3-HF treatment. 

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