Automatic Flame Photometric Determination of Potassium in Fertilizers. A. Elimination of Anion Exchange Cleanup. B. Using Direct Available P2O5 Extract

1965 ◽  
Vol 48 (6) ◽  
pp. 1095-1100
Author(s):  
James P Ussary ◽  
Charles W Gehrke
Keyword(s):  
Anion Exchange ◽  
Primary Standard ◽  
Photometric Determination ◽  
Photometric Method ◽  
Potassium Salts ◽  
Commercial Fertilizer ◽  
Aoac Official ◽  
Primary Standards ◽  
Standard Grade

Abstract Three primary standard grade potassium salts, eight Magruder check samples, and 18 commercial fertilizer samples were analyzed by three methods. Primary standards gave an average recovery of 100.0% and an average range of 0.21% K20. Magruder check samples averaged 0.09% K20 higher by the modified flame photometric method than the grand averages of the STPB results on the respective Magruder reports. The modified flame photometric method averaged 0.02% K20 lower than the official flame photometric method and 0.11% K20 higher than the official STPB method on 18 commercial fertilizer samples. The automatic flame photometric method, without anion exchange cleanup, is rapid enough for routine analysis and is as accurate and precise as the AOAC official methods. The method was also applied to the direct available P205 extract. Results on three primary grade potassium salts, seven Magruder check samples, and 13 commercial fertilizer samples were as accurate and precise as the official STPB method.

scholarly journals Characterization and Quantification of Selenoprotein P: Challenges to Mass Spectrometry

2021 ◽  
Vol 22 (12) ◽  
pp. 6283
Author(s):  
Jérémy Lamarche ◽  
Luisa Ronga ◽  
Joanna Szpunar ◽  
Ryszard Lobinski
Keyword(s):  
Mass Spectrometry ◽  
State Of The Art ◽  
Animal Health ◽  
Primary Standard ◽  
Selenoprotein P ◽  
Primary Standards ◽  
Analytical Approaches ◽  
Careful Investigation ◽  
Accurate Quantification

Selenoprotein P (SELENOP) is an emerging marker of the nutritional status of selenium and of various diseases, however, its chemical characteristics still need to be investigated and methods for its accurate quantitation improved. SELENOP is unique among selenoproteins, as it contains multiple genetically encoded SeCys residues, whereas all the other characterized selenoproteins contain just one. SELENOP occurs in the form of multiple isoforms, truncated species and post-translationally modified variants which are relatively poorly characterized. The accurate quantification of SELENOP is contingent on the availability of specific primary standards and reference methods. Before recombinant SELENOP becomes available to be used as a primary standard, careful investigation of the characteristics of the SELENOP measured by electrospray MS and strict control of the recoveries at the various steps of the analytical procedures are strongly recommended. This review critically discusses the state-of-the-art of analytical approaches to the characterization and quantification of SELENOP. While immunoassays remain the standard for the determination of human and animal health status, because of their speed and simplicity, mass spectrometry techniques offer many attractive and complementary features that are highlighted and critically evaluated.

Elimination of Aliquoting in Automated Flame Photometric Determination of K2O in Fertilizers

1984 ◽  
Vol 67 (4) ◽  
pp. 847-850
Author(s):  
Layna D Steele ◽  
Kelly J Ramsey ◽  
Peter F Kane
Keyword(s):  
Full Range ◽  
Flow Analysis ◽  
Photometric Determination ◽  
Photometric Method ◽  
Official Method ◽  
Significant Saving ◽  
Large Numbers ◽  
Continuous Flow Analysis ◽  
Automated Instrument

Abstract Current automated instrument systems used in conjunction with the official AOAC flame photometric method for K2O in fertilizer, 2.D06, all require a dilution step to bring the fertilizer extract to the appropriate concentration range. Two CFA (Continuous Flow Analysis) automated instrument systems are described which together eliminate aliquoting over the full range of fertilizer potassium, a significant saving of analyst effort if large numbers of samples are analyzed. The systems have performance characteristics well within the limits in the official method, and produce results comparable to current methods on routine samples.

Anion exchange extraction of tallium (III) and mercury (II) complex salts and application of the procedure to extraction-photometric determination of the microquantities of mercury (II)

2021 ◽  
Vol 87 (5) ◽  
pp. 20-26
Author(s):  
Yu. V. Matveichuk
Keyword(s):  
Methyl Orange ◽  
Anion Exchange ◽  
Photometric Determination ◽  
Large Mass ◽  
Hazard Class ◽  
Exchange Constants ◽  
Exchange Extraction ◽  
The Republic ◽  
Low Charge

The goal is to study the anion-exchange extraction of complex thallium (III) and mercury (II) halides (chlorides, bromides, iodides) by a method of a competing intermediate ion using the anions of various dyes — methyl orange, sodium picrate, 2,4-dinitrophenol, methyl red. Mercury (II) and thallium (III) are poisons of high toxicity. The developed method was used to study the anion-exchange extraction of acidocomplexes A solution of methyl orange trinonyloctadecylammonium (TNODA) in toluene was used as an extractant. The method provides determination of mercury (II) with an accuracy of ±2% when the concentration in the initial solution ranges within 2 – 8 × 10–8 mol/liter. It is shown that the values of the exchange constants for the same metal are larger for iodide complexes than for bromide and chloride ones. The extractability of metal halide complexes is mainly determined by their mass. Anions with a large mass have a large surface area, a low charge density, and are weakly hydrated, and thus are better extracted. The results of anion-exchange extraction were used to develop a procedure for the extraction-photometric determination of mercury (II) in granosan (ethylmercury chloride a prohibited insectofungicide of the 1st hazard class) the illegal use and storage of which could be a source of mercury pollution of groundwater in a number of regions of the Republic of Belarus. The relative error of determination does not exceed ±2%.

scholarly journals Determination of chromium (VI) in the dust of gas treatment plants in steelmaking plants.

2020 ◽  
pp. 42-44
Author(s):  
V. A. Makarov ◽  
T. K. Savosteenko
Keyword(s):  
Hexavalent Chromium ◽  
Raw Materials ◽  
Potassium Dichromate ◽  
Least Square Method ◽  
Photometric Determination ◽  
Least Square ◽  
Photometric Method ◽  
Gas Treatment ◽  
Gas Cleaning

The requirements for the content of hexavalent chromium in cements and raw materials for its manufacture are described. The problem with the utilization of dust from gas treatment plants of metallurgical plants at metallurgical enterprises is given. The influence of the chemical composition of the dust of gas cleaning plants of metallurgical plants on the determination of hexavalent chromium is established. A method for measuring the hexavalent chromium in the dust of gas cleaning plants of metallurgical plants by the photometric method is described. A method has been developed for extracting hexavalent chromium from dust at the cleaning units of metallurgical plants for subsequent photometric determination. An extraction method has been established to prevent underestimation of the hexavalent chromium content. The determination of hexavalent chromium was based on the formation of a blue-violet complex with diphenylcarbazide. Calibration was carried out on aque solutions with a known concentration of hexavalent chromium. For the preparation of calibration solutions, potassium dichromate of chemical purity was used. The concentration of hexavalent chromium in each calibration solution was carried out by a calculation method, overlapping the entire measurement range. The measurement of optical density was carried out on a photoelectric colorimeter type KFK-3, at a wavelength of 540 nm. Analysis of the obtained calibration dependence showed a good correlation. The calibration factor was calculated using the least square method. Extraction of hexavalent chromium from the sample to be analyzed was performed with water. The reducing effect of iron was eliminated with a solution of phosphoric acid. The developed technique is used when conducting certification control of dust from gas cleaning units of metallurgical plants, as well as during research.A validation procedure was carried out. Obtained acceptable limits of repeatability and reproducibility of the method.

Automation of the Flame Photometric Method for Potassium in Fertilizer Grade Potassium Salts

1965 ◽  
Vol 48 (4) ◽  
pp. 865-868
Author(s):  
James P Ussary ◽  
Charles W Gehrke
Keyword(s):  
Photometric Method ◽  
Potassium Salts ◽  
Considerable Saving ◽  
Large Numbers ◽  
Relative Standard ◽  
Aoac Official ◽  
Standard Deviations ◽  
Flame Method ◽  
Analytical Time

Abstract Five selected commercial salts and two reagent grade salts were analyzed for potassium at least 10 times independently by both the automatic flame photometric method and the AOAC official STPB method. The flame photometric results were as precise and accurate as the official STPB results. The relative standard deviations were 0.36% K2O for the automated flame method and 0.32% K2O for the STPB method. The averages of the results (100.1%) on the reagent grade salts were very close to the theoretical values. The automatic flame photometric method for potassium in fertilizer grade potassium salts is accurate and precise, and results in a considerable saving in analytical time, especially for laboratories routinely analyzing large numbers of samples.

scholarly journals Simple photometric determination of free cyanide ion in aqueous solution with 2,6-dichlorophenolindophenol

2006 ◽  
Vol 4 (2) ◽  
Author(s):  
Abdollah Yari ◽  
Kazem Kargosha
Keyword(s):  
Aqueous Solution ◽  
Photometric Determination ◽  
High Accuracy ◽  
Photometric Method ◽  
Free Cyanide ◽  
Optimal Conditions ◽  
Cyanide Ion ◽  
Accuracy And Precision ◽  
Photometric Titration

AbstractIn this work, a simple photometric method with high accuracy and precision for measuring trace amounts of free cyanide ion in aqueous solution is demonstrated. Under the evaluated conditions, we could determine CN− concentration in the range of 5–70 ppm easily. The work is based upon the photometric titration of CN− with Co(II) in the presence of 2,6-dichlorophenolindophenol (DCPIP) at λmax = 602 nm in aqueous solution. The optimal conditions, such as pH, ionic strength, and concentration of chromopher were evaluated. The interence effect of many other cations and anions studied and the results are given here. The optimized titration was successfully used to determine the concentration of free cyanide ion in aqueous solutions.

Multicenter Evaluation of a Chromogenic Substrate Method for Photometric Determination of Prothrombin Time

1987 ◽  
Vol 58 (03) ◽  
pp. 856-865 ◽  
Author(s):  
F Dati ◽  
M Barthels ◽  
J Conard ◽  
J Flückiger ◽  
A Girolami ◽  
...  
Keyword(s):  
Prothrombin Time ◽  
Anticoagulant Therapy ◽  
Photometric Determination ◽  
Coagulation Factors ◽  
Stable Phase ◽  
Photometric Method ◽  
Sensitivity Index ◽  
Chromogenic Substrate ◽  
Plasma Samples

SummaryA multicenter study of a chromogenic substrate method for photometric determination of prothrombin time was conducted in order to evaluate its clinical application. Seven laboratories pailicipaled in the study using a total of 742 plasma samples from 417 patients on oral anticoagulant therapy, 261 healthy subjects and 64 patients with different diseases especially of the liver as well as 30 patients with hereditary deficiency of coagulation factors II, V, VII, X. The chromogenic PT method was compared to a standardized coagulometric PT assay which uses the same sensitive human placenta thromboplastin calibrated against international reference preparations. A high correlation of the prothrombin ratio values of the chromogenic and the coagulometric assay was obtained in 402 plasma samples (r = 0.940; y = 1.02x − 0.1). The study showed that the chromogenic PT reagent is sensitive to deficiency of the coagulation factors of the extrinsic pathway but not affected by heparin up to 1 IU/ml because of the heparin antagonist added. The precision (coefficient of variation) of the photometric method ranged between 0.6 and 3% (intraassay CV) and between 1.4 and 5.8 (interassay CV). The International Sensitivity Index (ISI) obtained for the used lot was 1.09. The therapeutical range in percentage activity for patients in a stable phase of an anticoagulant therapy was found to be from 15 to 27 percent of normal. The results of the clinical evaluation proved the good comparability of the new chromogenic PT test with coagulometric methods, its high factor sensitivity, good reproducibility and easy performance.

scholarly journals Determination of traces of chlorine in aluminum by the anion exchange-photometric method

1972 ◽  
Vol 21 (4) ◽  
pp. 480-486 ◽  
Author(s):  
Tsutomu FUKASAWA ◽  
Kazuhiko KATAGIRI
Keyword(s):  
Anion Exchange ◽  
Photometric Method
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