The research activity covers topics related to inorganic and organic chemistry, gases and bio-analysis. Analytical procedures for both trace metals as well as organic compounds are developed and tested. The gravimetric method and laser spectroscopy procedures are developed and applied for the primary standards preparation of different gases and their mixtures. Methods based on spectroscopy measurements are under investigation for bioanalysis in biochemical studies. Most of the results of the research activities are obtained in the framework of international joint research programs promoted by CIPM, EUROMET and EURACHEM. On the basis of these studies, applied researches in environmental, toxicological and medical related problems are also in progress.
The activity carried out dealt with the preparation of gravimetrical primary gas mixtures, gas analysis and also organic compounds analysis. The equipment for the precision weighing of the cylinders was tested to optimise and characterize the system itself. A sensitivity of 1 mg per division was verified. Some primary mixtures of CO2 in N2 with nominal concentration of 400 µmol/mol were prepared. The composition of such mixtures will be assigned according to the gravimetric value. The channel of the NDIR analyser, for the determination of CO2 and CO at emission level, was characterized and calibrated. Participation in the EUROMET/METCHEM international comparison (EUROMET Project no. 833) for the determination of polychlorinated biphenyls (PCBs) in organic solution gave a satisfactory result. This represents a good starting point for the new research activity in organic analysis.
System for cylinders precision weighing.
The research activity mainly addressed the development and application of radioanalytical (Neutron Activation Analysis) and spectrochemical (Graphite Furnace-Atomic Absorption Spectroscopy) techniques employed in trace elements studies. Within the framework of the activities of the IAWG of the CCQM the Unit participated in several key and pilot interlaboratory comparisons. Environmental, toxicological and technological materials were investigated as Reference Materials (RMs) in collaboration with NIST (USA), IAEA (ONU) and IRMM (EU). In the field of applied research, the activity focused on atmospheric pollution related problems (indoor, urban, remote areas, biomonitors) as well as on studies related to neurodegenerative diseases (Parkinson). This last research was accomplished in collaboration with the CNR Institute of Biomedical Technology.
Research nuclear reactor TRIGA MarkII of Pavia University.
The research was devoted to the study and development of primary gas standards of new conception, referred to spectroscopic molecular constants and described by physical equations. The activities concerned experimental and theoretical studies on the ozone in primary air standard for accuracy assessment, then tested in a first international comparison. In a joint project with the Agency for the Protection of the Environment and for the Technical Services (APAT), a traceability chain for the calibration of Italian ozone monitoring network analyzers has been realized. To develop a water vapor in air spectroscopic primary standard at trace level, a highly dry air dynamic generation system was constructed and tested to 35 nmol/mol, in cooperation with the INRIM "hygrometry" group, by a chilled mirror hygrometer. As regards bio-analysis, dimensional and geometrical characteristics of 565 nm CdSe Q-dots have been analyzed (TEM) and emitting power has been measured.
The activity concerning the potentiometric measurement of pH has focused on the comparison of secondary (glass electrode) measurements, obtained by considering either the activity (paH) or the concentration (pcH) scale of the hydrogen ions, with primary (Harned cell) measurements. It was shown that fitting and comparable paH and pcH results are attainable if activity coefficient evaluation is performed using better estimates of the ionic strength, according to an enhanced application of the Debye-Hückel theory. Furthermore, INRIM took part in an international comparison, CCQM-P82, for the pH measurement of a borate buffer. The results obtained were compatible with the reference value.