An infant formula certified reference material (CRM) for the analysis of vitamins was developed. Vitamin A, folic acid, niacin, were certified and their stability has been monitored by using isotope dilution-liquid chromatography/mass spectrometric (ID-LC/MS) methods developed in our laboratories as primary methods for the corresponding analytes. Certification of α-, δ-, and γ- tocopherols in the CRM is undergoing at the time of submitting this proceeding.
The European Food Information Resource (EUROFIR) is a network of national Food Composition Databank (nFCDB) compilers that aims to develop, manage and publish food composition data and promote international cooperation and harmonization through improved data quality, database search ability and standards. The aim of this work is to study the role of metrology in harmonization of nFCDB. The criteria for use of nFCDBs to assist measurement processes in dietary assessment, epidemiology, food processing and food technology are described in relation to the EuroFIR quality management framework....
A calibration method was developed for the quantification of isocyanates in cork stoppers agglomerates. Bracketing and multipoint calibration curve was applied to a in-house optimized UPLC/DAD analytical method. The calibration curves were obtained by regression analysis using experimental points that covers the range of concentrations expected in real samples. A contaminated real sample was injected and MDI concentration was 6.2% and 6.4% when calibration methods to calculate the content were multipoint or bracketing, respectively. According with our results both methods are complementary...
This paper will give an overview to the status of metrology in nutritional and functional components of food in China, covering traceability policy, CRMs, analytical methods, international comparisons, CMCs, and show a outlook.
A multivitamin certified reference material (CRM) was developed for the analysis of nicotinamide. The certification value was assigned by ID-LC/MS as primary method for nicotinamide. The stability monitoring was conducted periodically, and the stability monitoring results agree with the certified value within their uncertainties.
The standard ISO/IEC 17025:2005 demands from calibration laboratories that the "participation in a suitable programme of interlaboratory comparisons is required where possible". In 2009, the working group of the German DKD concerned with acceleration and vibration decided to start such an interlaboratory comparison programme regarding the measurand acceleration and related quantities. This paper presents the set-up and organization as well as some combined results of this programme.
Ultrasonic power measurement in the megahertz frequency range is undertaken according to the physical principle of radiation force. In this case, a device named "radiation force balance" is habitually used for output powers lower than about 20 W. The construction of a radiation force balance presupposes the use of either a reflecting or an absorbing target. In this paper, it is detailed a statistical analysis of 5 different absorbing targets used in an implementation of a radiation force balance measurement device. The output frequency was 3.5 MHz, and two transducers (nominal diameter of...
ICP® based accelerometers have become widely used in the field of vibration measurement as general purpose sensors. Charge mode accelerometers have historically been used as the reference for back to back comparison calibrations. This paper introduces the concept that the use of properly constructed ICP® based accelerometers result in a much simpler, more reliable and easier to use calibration system than charge mode accelerometer based systems. Historical data will be provided which documents the long term stability of selected ICP® reference sensors. This paper is relevant to anyone...
Low Frequency accelerometer calibration is generally time consuming and requires special considerations and excitation techniques. A new class of reference sensor for use in low frequency accelerometer calibration is introduced. This paper also outlines challenges of low frequency calibration and details principal sources of error. New developments in low frequency accelerometer calibration excitation technology are introduced. Comparison to manufacturers primary calibration of an artifact as well as comparison to primary means is presented.
A unique type of fiber optic accelerometer based on wavelength modulation by the Bragg grating principle has been developed. Testing, characterization and calibration of such transducers represent a challenge since they are not readily compatible with conventional data acquisition platforms. To overcome this technical challenge a system based on a precision vibration exciter driven by a newly released vibration controller has been configured. With this system the optical transducer system can be tested and the frequency response determined. This shaker based vibration test system represents...