Digest samples

A procedure for using a microwave oven to digest samples of Ni ore and to dry precipitates of nickel-dimethylgloxime is described in this experiment. 

Known concentrations of Sn solutions were spiked Into acid digested samples of Ps. 244 which had been exposed to 10 ppm solutions of Bu Sn (x = 0,1,2,3). Atomic absorption analysis of these samples allowed for the calculation of the amount of tin accumulated on the cell by the method of multiple additions Q6). 

Pd removal was determined as follows. An aliquot of a representative liquid or solid sample was accurately weighed and subsequently digested by refluxing in nitric and/or hydrochloric acid using a closed vessel microwave procedure (CEM MARS5 Xpress or Milestone Ethos EZ). Cooled, digested samples were diluted, matrix matched to standards, and referenced to a linear calibration curve for quantitation an internal standard was employed to improve quantitation. All samples were analyzed by an Inductively Coupled Plasma Mass Spectrometer or ICP/MS (Perkin Elmer SCIEX Elan DRCII) operated in the standard mode. 

The Cr203 content of each catalyst was determined by atomic absorption spectroscopy (Varian/Spectr AA-20 plus) on acid-digested samples. Total surface areas were determined by a single point BET method (nitrogen adsorption-desorption at 77.5 K) using a mixture of 29.7% N2 in helium. Samples were wet-loaded into the flow tube and dried at 423 K in a hydrogen flow for 15 minutes and then for another 30 minutes at 513 K before cooling in helium. 

ASTM. 1998a. ASTME1613. Standard test method for analysis of digested samples for lead by inductively coupled plasma atomic emission spectrometry (ICP-AES). Flame Atomic Absorption (FAAS), or Graphite Furnace Atomic Absorption (GFAA) Techniques. American Society for Testing and Materials. 

Microwave digestion Sample heated with acids using microwaves under controlled temperature and pressure Metals in organic/inorganic solid samples (e.g. metals in sediments)... 

Jurka and Carter [50] have described an automated determination of down to O.lpg L 1 mercury in river sediment samples. This method is based on the automated procedure of El-Awady [51] for the determination of total mercury in waters and waste waters in which potassium persulphate and sulphuric acid were used to digest samples for analysis by the cold vapour technique. These workers proved that the use of potassium permanganate as an additional oxidizing agent was unnecessary. 

The estabhshed method for phosphorus analysis using a heated block involves a lengthy digestion with sulphuric acid. Furthermore, it is labour and space intensive and requires the digested sample to undergo a second stage for the final analytical determination. 

The performance of the system was clearly demonstrated for a wide range of foodstuffs. The data for the NBS (National Bureau of Standards) bovine hver (Table 4.1) shows that the automatic system is capable of giving accurate results. Samples were freeze-dried on receipt. Measurements on manually digested samples were made by atomic-absorption spectrophotometry, and by plasma-emission spectrometry on automatically digested... 

Lester et al. [24] have described a robotic system for the analysis of arsenic and selenium in human urine samples which demonstrates how robotics has been used to integrate sample preparations and instrument analysis of a biological matrix for trace elements. The robot is used to control the ashing, digestion, sample injection and operation of a hydride system and atomic absorption instrument, including the instrument calibration. The system, which routinely analyses both As and Se at ppb levels, is estimated to require only... 

All assays performed on digester samples were conducted in 100 mM Tris buffer pH 7.5 with substrate incubations at 37 C. Glucose-releasing assays used the same Tris buffer with 0.5% sodium azide added. Colorimetric products from enzyme assays were detected and recorded using a Milton-Roy model 601 spectrophotometer equipped with sipper and data printer. 

Schnitzius, J. M., Hill, N. S., Thompson, C. S. and Craig, A. M. 2001. Semi-quantitative determination of ergot alkaloids in seed, straw, and digested samples using a competitive enzyme-linked immunosorbent assay. Journal of Veterinary Diagnostic Investigation, 13 230-237. 

Acid digestion sample solutions should contain 0.5% HNO3 AAS, direct aspiration Method 249.2 1 pg/L Not applicable EPA 1983... 

Attribute Ratings. Panelists perceive a variety of characteristics in products. When the product developer systematically varies the formulation over a systematically wide range, the panelist may perceive an entire spectrum of different characteristics. One can trace these characteristics back to the specified formulation levels, but only if the panelist has had a chance to evaluate the characteristics by means of scaling. In this study the panelists rated a variety of different attributes after tasting each digestive sample. 

Ultrasound pseudo-digestion sample treatment was studied to extract metals from fish muscle tissue. Relevant variables were finally optimised with a central composite design... 

Analysis of major elements (except Si) and total phosphorus on bomb-digested samples was accomplished by inductively coupled plasma emission spectrometry (ICP, ARL model 34,000). Silicon was analyzed colorimetrically (14). Phosphorus in total digests was also determined colorimetrically by the method of Murphy and Riley (15), as modified by Erickson (16). To avoid interference from fluoride ion used in the digestion technique, sample volumes were restricted to <1.5 mL in the standard P analytical protocol. 

Digest sample with lipase, extract with pentane. 

Fats, oils, and dairy products digest sample with lipase, extract with hexane. Purify hexane extracts obtained from either extraction technique by silica solid-phase extraction in the sample cleanup mode. The internal standard is phylloquinone 2,3-epoxide (unlabeled for UV detection and tritium labeled for coulometric detection). 

Digest sample with HNO 3 evaporate to dryness add glacial acetic acid and adjust to pH 3 add ammonium pyrrolidine dlthlo-carbamate and extract with methyl 1sobutyl ketone heat organic organic phase to dryness dissolve residue with HNO3... 

Digest sample with 70% HFP-AES or 70% perchloric acid and concentrated HN03 ... 

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