Solid-phase fluorescence in chemical test methods of analysis based on the principles of planar chromatography

2009 ◽  
Vol 64 (11) ◽  
pp. 1189-1192 ◽  
Author(s):  
V. G. Amelin ◽  
N. S. Aleshin
Keyword(s):  
Solid Phase ◽  
Test Methods ◽  
Planar Chromatography ◽  
Chemical Test ◽  
Methods Of Analysis

Identification of Fe (IV) in oxides by chemical test methods

2020 ◽  
Vol 86 (6) ◽  
pp. 5-13
Author(s):  
N. V. Barkovskii
Keyword(s):  
Redox Reactions ◽  
Alkaline Earth ◽  
Solid Phase ◽  
Test Methods ◽  
Alkaline Media ◽  
Chemical Test ◽  
Phase Synthesis ◽  
Organic Reagents ◽  
Standard Redox Potential ◽  
First Time

A comparative analysis of the behavior of oxides containing Fe (III) and Fe (IV) in redox reactions with organic and inorganic reagents has been carried out. SrFeO3-x oxide obtained by solid-phase synthesis from SrCO3 and Fe2O3 has been an object to develop test methods. It has been shown that Fe (IV) exhibits the properties of a stronger oxidizer than Fe (III), thus providing a set of reagents which enable identification of Fe (IV): hydrobromic acid, Fe2+ complex with V (IV), and Mn (II) salts, and organic reagents, namely, amines (diphenylamine, o-tolidine, benzidine) and dyes (methyl red). Potentiometric method proved stronger oxidative properties of Fe (IV) compared to Fe (III) revealed in different character of changes in EMF during dissolution of the corresponding oxides in HCl. SrFeO3–x oxide does not oxidize Mn (II) to Mn (VII), Cr (III) to Cr (VI), Ce (III) to Ce (IV) in acidic media, and Cu (II) to Cu (III) in alkaline media. Since the oxide under study oxidize Cl– = 1.3583 V) and Br– = 1.087 V) ions to the corresponding halogens, but does not oxidize Mn2+ to = 1.51 V), an estimated value of the standard redox potential is ~1.4 V. We have developed for the first time a system of analytical tests for differentiation of Fe (IV) and Fe (III) which can provide monitoring of the synthesis of complex oxides and phase formation in the systems containing iron, alkali and alkaline earth metals.

The SMRI-NIRS technology: development, validation and benefit

2021 ◽  
pp. 354-359
Author(s):  
Stephen N. Walford
Keyword(s):  
South African ◽  
Near Infrared ◽  
Technology Development ◽  
Correlation Coefficients ◽  
Test Methods ◽  
Analysis Method ◽  
Prediction Equations ◽  
Conventional Analysis ◽  
Methods Of Analysis ◽  
Conventional Methods

The Sugar Milling Research Institute NPC (SMRI) has developed a simple to use near-infrared spectroscopy (NIRS) transmission-based analysis method as an alternative to conventional methods for analysis of sugarcane factory stream samples. The technology provides rapid, simultaneous analysis of refractometric dry substance (rds), polarimetric sugar, sucrose, glucose, fructose, conductivity ash contents as well as colour and pH for all streams and additionally, dry solids for final molasses and eliminates the need for sample clarification chemicals. The analyte prediction equations were developed using conventional results of samples from 14 South African factories, analysed at SMRI using SANAS/ISO17025 accredited test methods, and NIRS scans of the same samples using up to 16 different NIRS instruments. The NIRS analyte prediction equations were validated against more than 1,500 independent factory samples that had been analysed by conventional methods of analysis, including samples from factories outside South Africa. The reproducibility of the NIRS results were equivalent to existing conventional analysis reproducibility values (juice and final molasses) and previously undocumented values determined for this study for conventional raw house analysis methods. Correlation coefficients of greater than 0.97 were recorded for all major analytes and greater than 0.9 for minor analytes when predicted results were compared against conventional results. A maintenance protocol was also developed to ensure that the prediction equations remain robust and can account for sample matrix variations that can occur from season to season. The SMRI-NIRS technology was installed at all 14 South African factories and found to be robust and give equivalent results to conventional methods of analysis.

Planar Chromatography for Screening of Ivermectin Residues in Swine and Cattle Tissues

1995 ◽  
Vol 78 (5) ◽  
pp. 1141-1144 ◽  
Author(s):  
Jean-Pierre Abjean ◽  
Murielle Gaugain
Keyword(s):  
Solid Phase Extraction ◽  
Solid Phase ◽  
Tissue Sample ◽  
Phase Extraction ◽  
Planar Chromatography ◽  
Qualitative Detection ◽  
Cattle Meat

Abstract A method was developed for qualitative detection of ivermectin residues. It involves extraction of 1 g tissue sample with 5 mL acetonitrile and C18 solid-phase extraction. After derivatization with tri-fluoroacetic anhydride, the extract is purified again on the same but previously reconditioned C18 column. The eluate is evaporated, and the residue is diluted in methanol. The method allows detection of residues in swine and cattle meat, liver, and fat at levels as low as 5 μg/kg.

Standards Development for the Characterization of Quantum Dot Suspensions and Solids

2009 ◽  
Vol 1207 ◽  
Author(s):  
Lynn Davis ◽  
Seth Coe-Sullivan ◽  
Oleg Shchekin ◽  
K.C. Mishra ◽  
Madis Raukas ◽  
...  
Keyword(s):  
Solid Phase ◽  
Test Methods ◽  
Standard Test ◽  
Technical Committee ◽  
Test Method ◽  
Solid Matrix ◽  
Integrating Sphere ◽  
International Electrotechnical Commission ◽  
Preparation Methods ◽  
External Stimuli

AbstractLuminescent nanoparticles such as quantum dots (QDs) are beginning to appear in SSL devices and other commercial products. The allure of QDs in SSL these applications is the potential to provide enhanced device performance (e.g., improved energy efficiency, better color rendering properties, etc.) than is possible with conventional technologies. When used in SSL and other applications, QDs are typically incorporated into or coated onto a solid organic or inorganic matrix and then are excited using external stimuli (e.g., blue light with a maximum wavelength of 450 nm). This structure is vastly different from the colloidal environment in which QDs are typically synthesized and characterized. Bridging the gap between the measurements typically acquired by QD providers and those needed by potential end-users is currently difficult due to the absence of agreed upon standard test methods. Measurements taken in colloidal QD suspensions often do not translate to solid-phase material characterizations due to a variety of factors including sample preparation methods (e.g., temperature, solvents, etc), QD concentrations, and effects arising from the presence of the solid matrix. Additionally, solid samples are more likely to exhibit diffuse reflectance and/or diffuse transmittance necessitating the use of an integrating sphere and a computer-controlled spectrometer to acquire accurate readings. This paper discusses the development of a standard test method to measure the quantum efficiency of QDs contained in solid organic and inorganic matrices. This standard is being developed under the auspices of the International Electrotechnical Commission, Technical Committee 113 on Nano-electrotechnologies.

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