Evaluation of INAA–anticoincidence counting for measuring nanogram levels of vanadium in relatively high-salt nutritional reference materials

Merits and limitations of layered and ion implanted specimens as possible reference materials to calibrate spatially resolved analytical techniques are discussed and illustrated for the case of gold analysis in minerals by means of x-ray spectrometry with the EPMA. To overcome the random heterogeneities of minerals, thin film deposition and ion implantation may offer an original approach to the manufacture of controlled concentration/ distribution reference materials for quantification of trace elements with the same matrix as the unknown.In order to evaluate the accuracy of data obtained by EPMA we have compared measured and calculated x-ray intensities for homogeneous and heterogeneous specimens. Au Lα and Au Mα x-ray intensities were recorded at various electron beam energies, and hence at various sampling depths, for gold coated and gold implanted specimens. X-ray intensity calculations are based on the use of analytical expressions for both the depth ionization Φ (ρz) and the depth concentration C (ρz) distributions respectively.

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Dissolution of α-Iron (Hydr)oxides by Trihydroxamate and Catecholate Siderophores and Oxalate Ligands at High Salt Concentrations and pH 3-6

Environmental Science & Technology ◽

10.1021/es048751e ◽

1967 ◽

Vol 0 (0) ◽

pp. 0-0

Author(s):

J. Cervini-Silva ◽

G. Sposito

Keyword(s):

High Salt

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The Relation Between VIIIR:AG and VIII:C Studied with Two Antisera

10.1055/s-0038-1665801 ◽

1979 ◽

Author(s):

H. P. Muller ◽

N. H. van Tilburg ◽

R. M. Bertina ◽

J. J. Veltkamp

Keyword(s):

Molecular Weight ◽

High Salt ◽

Low Molecular Weight ◽

Gel Chromatography ◽

Specific Antibodies ◽

Specific Effects ◽

Normal Plasma ◽

Coagulant Activity ◽

Sterical Hindrance ◽

Inhibitory Antibodies

FVIII was separated into low molecular weight FVIII (LMW FVIII) and high molecular weight FVIII (HMW FVIII) by gel chromatography in the presence of high salt concentration or by high salt elution of LMW FVIII from FVIII bound to anti HMW FVII-Sepharose. Specific antibodies were raised in rabbits against HMW FVIII and LMW FVIII. After removal of the contaminating anti HMW activities the rabbit anti LMW FVIII was still able to neutralize the FVIII coagulant activity of normal plasma and of IMW FVIII with canparable efficiency and it had no effect on the VIIIR:WF of FVIII in normal plasma or in HMW FVIII. Anti LMW FVIII does not bind to HMW FVIII and does not precipitate FVIII as tested by counter immunoelectrophoresis. Rabbit anti HMW FVIII precipitates FVIII in normal plasma, inhibits VIIIR:WF activity, while it has no effect on the FVIII coagulant activity of LMW FVIII. The coagulant activity of FVIII in normal plasma is slightly inhibited by anti HMW FVIII presumably by non-specific effects (sterical hindrance). It is concluded that inhibitory antibodies against VIII:C raised in rabbits recognize antigenic structures only present on LMW FVIII. Antibodies against HMW FVIII raised in rabbits appears to recognize structures only present on HMW FVIII.

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Development of reference materials with the composition of propyl and isopropyl alcohol solutions

Izmeritel`naya Tekhnika ◽

10.32446/0368-1025it.2020-6-66-72 ◽

2020 ◽

pp. 66-72

Author(s):

Irina A. Piterskikh ◽

Svetlana V. Vikhrova ◽

Nina G. Kovaleva ◽

Tatyana O. Barynskaya

Keyword(s):

Reference Materials ◽

Measurement Errors ◽

Isopropyl Alcohol ◽

Certified Reference Materials ◽

Toxic Substances ◽

Biological Objects ◽

Margin Of Error ◽

Measurement Results ◽

And Control ◽

Characteristic Mass

Certified reference materials (CRM) composed of propyl (11383-2019) and isopropyl (11384-2019) alcohols solutions were created for validation of measurement procedures and control of measurement errors of measurement results of mass concentrations of toxic substances (alcohol) in biological objects (urine, blood) and water. Two ways of establishing the value of the certified characteristic – mass consentration of propanol-1 or propanol-2 have been studied. The results obtained by the preparation procedure and comparison with the standard are the same within the margin of error.

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Problems of ensuring metrological traceability of measurement results of indicators of quality for food products and food raw materials

Izmeritel`naya Tekhnika ◽

10.32446/0368-1025it.2020-3-64-70 ◽

2020 ◽

pp. 64-70

Author(s):

Mariya Y. Medvedevskikh ◽

Anna S. Sergeeva

Keyword(s):

Reference Materials ◽

Mass Fraction ◽

Nutritional Value ◽

Animal Feed ◽

Raw Materials ◽

Meat Products ◽

Metrological Traceability ◽

Food Products ◽

Freeze Dried ◽

Measurement Results

The article raises the problem of ensuring metrological traceability of the measurement results of indicators of quality and nutritional value for food products and food raw materials: water (moisture), nitrogen (protein, crude protein), fat, ash and carbohydrates. The problem under consideration can be solved by applying reference materials of food composition, traceable to state primary measurement standards GET 173-2017 and GET 176-2019 and primary reference measurement procedures (PRMP), for attestation of measurement procedures and accuracy checking of measurement results. The article discusses the results of the PRMP development of mass fraction of fat, ash and carbohydrates in food products and food raw materials, as well as mass fraction of crude fat (oil content) in oil crops seeds and products based on them. The paper also presents metrological characteristics of reference materials of composition of dry dairy products, grain-milk dry porridges for nutrition of babies, grain dry porridges for nutrition of babies, egg powder, freeze-dried meat products, animal feed. The results of the work allow for building a chain of metrological traceability from GET 173-2017, GET 176-2019 and PRMP to routine measurement procedures, thereby ensuring the uniformity of measurements of nutritional value of food products.

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