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A new cadmium zinc telluride (CZT) portable spectrometric system called OMEGA has been developed at CEA/LETI for high-energy applications like spent fuel assay in response to needs in the nuclear industry. The unit has beendesigned to operate at room temperature under water. The CZT OMEGA system is based on a single 10 x 10 x 10 [mm.sup.3] CZT detector associated with a single electronics channel. To improve performance, the system incorporates several technologies including: an electrode design named the 'Mixed' electrode which combines a noncontacting Frisch grid and the pixel field effect to obtain maximum sensitivity from the 10 x 10 x 10 [mm.sup.3] CZT detector, a single hybrid preamplifier designed to reduce noise, an electronics board configured to enhance count rate capabilities and finally, electron bi-parametric (BP) correction (pulse height corrected via measurement of rise time) to improve both energy resolution and detection efficiency. This paper reports the most recent results obtained with the CZT OMEGA spectrometric system at high energy ([sup.137]Cs and [sup.152]Eu sources) at both low and high count rate: spectrometric performance shows an energy resolution of 1% FWHM at 662 keV (0.8% at 1408 keV) from 1 kcps to 50 kcps, deteriorating to 2% FWHM at 200 kcps. Index Terms--[gamma]-ray detectors, bi-parametric correction, cadmium zinc telluride (CZT), charge sensitive preamplifier, count rate, energy resolution, noncontacting Frisch grid.

Highlights • Long term time series returns fundamental information on climate studies. • Short term time series returns information on temperature dynamics. • Comparison of heterogeneous series should account local dynamics and uncertainty. • RMN data represent an additional source of information in coastal areas. Abstract The aim of this paper is to give an overview of the various measurement collections that contribute to the observation of Sea Surface Temperature in Italian Seas. Long term time series are collected since the 19th century but are affected by a large systematic errors. Despite the lack of accuracy, their contribution to the analysis of trends is fundamental into the climate change context. On the other hand, recent systematic observations are more accurate and continuous in space and time. Short term time series better define the status of the temperature during the last years in term of variability and dynamics. [ABSTRACT FROM AUTHOR]

A new cadmium zinc telluride (CZT) portable spectrometric system called OMEGA has been developed at CEA/LETI for high-energy applications like spent fuel assay in response to needs in the nuclear industry. The unit has been designed to operate at room temperature under water. The CZT OMEGA system is based on a single 10 × 10 × 10 mm³ CZT detector associated with a single electronics channel. To improve performance, the system incorporates several technologies including: an electrode design named the "Mixed" electrode which combines a noncontacting Frisch grid and the pixel field effect to obtain maximum sensitivity from the 10 × 10 × 10 mm³ CZT detector, a single hybrid preamplifier designed to reduce noise, an electronics board configured to enhance count rate capabilities and finally, electron bi-parametric (BP) correction (pulse height corrected via measurement of rise time) to improve both energy resolution and detection efficiency. [ABSTRACT FROM AUTHOR]

A fully three-dimensional (3D) model of a CdZnTe semiconductor gamma-ray detector is presented. It takes into account the physical phenomena involved in the detection process and models the readout electronic response and noise. The model successively involves the finite element transient computation of the adjoint transport equation, the Monte Carlo simulation of the photon transport and the electronic signal processing including an accurate noise model. The simulation is fast and accurate because the solution of the adjoint equation allows us to obtain a continuous mapping of the induced charge collection (at any time and any interaction point) with a single 3D transient finite element computation. The simulation outputs are pulse height spectra and biparametric (rise time versus pulse height) spectra. [Copyright &y& Elsevier]

Microplastics (MPs) are present in fresh, brackish, or marine waters. Micro- and macroinvertebrates can mistake MPs or small microplastics (SMPs, <100 μm) to be food particles and easily ingest them according to the size of their mouthparts. SMPs may then block the passage of food through the intestinal tract (i.e. hepatopancreas), accumulate within the organism, and enter the food web. Pacific oysters (Crassostrea gigas) are allochthonous filter-feeding bivalve mollusks, which have been introduced in coastal seas around the world in both natural banks and farms. Considering their economic and ecological value, these bivalves have been chosen as a model to study the ingestion of SMPs. A novel method for the extraction and purification of SMPs in bivalves was developed. Quantification and simultaneous polymer identification of SMPs using Micro-FTIR (Fourier Transform Infrared Spectroscopy) were performed, with a limit of detection for the particle size of 5 μm. Unlabelled Image • New methods developed for gills and hepatopancreas of Crassostrea gigas • Quantification and identification of small microplastics (<100 μm) using Micro-FTIR • Quantification and identification of additives and natural fibers using Micro-FTIR [ABSTRACT FROM AUTHOR]

Graphical abstract Unlabelled Image Highlights • Presence and impact of derelict fishing gear were studied in North Adriatic outcrops. • The occurrence of derelict fishing gear was evidenced in half of the monitored areas. • A total of 362 items were removed by scuba divers. • The complexity of macro-benthic community gradually improved in the cleared areas. • Cryptic fish species occupied cracks previously obstructed by derelict fishing gear. [ABSTRACT FROM AUTHOR]