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X-ray Compton spectroscopy is one of the few direct probes of the electron momentum distribution of bulk materials in ambient and operando environments. We report high-resolution inelastic X-ray scattering experiments with high momentum and energy transfer performed at a storage-ring-based high-energy X-ray light source facility using an X-ray microcalorimeter detector. Compton profiles were measured for lithium and cobalt oxide powders relevant to lithium-ion battery research. Spectroscopic analysis of the measured Compton profiles shows high-sensitivity to the low-Z elements and oxidation states. The lineshape analysis of the measured Compton profiles in comparison with computed Hartree-Fock profiles is limited by the resolution of the energy-resolving semiconductor detector. We have characterized an X-ray transition-edge sensor microcalorimeter detector for high-resolution Compton scattering experiments using a bending magnet source at the Advanced Photon Source (APS) with a double crystal monochromator providing monochromatic photon energies near 27.5 keV. The momentum resolution below 0.16 atomic units was measured yielding an improvement of more than a factor of 7 over a state-of-the-art silicon drift detector for the same scattering geometry. Furthermore, the lineshapes of narrow valence and broad core electron profiles of sealed lithium metal were clearly resolved using an X-ray microcalorimeter detector compared to smeared and broadened lineshapes observed when using a silicon drift detector. High-resolution Compton scattering using the energy-resolving detector shown here presents new opportunities for spatial imaging of electron momentum distributions for a wide class of materials with applications ranging from electrochemistry to condensed matter physics., Comment: The following article has been submitted to Applied Physics Letters

We have investigated by means of noise spectroscopy the transport properties of half-metal La0.7Ba0.3MnO3 (LBMO) thin films deposited on MgO substrates. A reduced metal–insulator transition temperature and a peculiar noise behaviour are observed in the films grown on MgO substrates, when compared with similar films grown on SrTiO3 substrates. In particular, a large increase in noise is observed below the metal–insulator transition temperature, associated with a current induced reduction in the excess noise level. This finding is explained in terms of the spin torque effect between regions with depressed Curie temperatures among the ferromagnetic metallic domains. The proposed theoretical model, taking into account the half-metal character of manganites, describes well the experimental data.

Irradiation of hake (Merluccius merluccius hubbsii) fillets with 500 krad (5 k Gy) of Co60 gamma rays caused a delay in the formation of volatile acids during storage under refrigeration at 4–5°C. Loss in organoleptic acceptability could be correlated with the increase in volatile acids both in the unirradiated and irradiated fish stored at 4–5°C, suggesting that the volatile acids number (VAN) can be a useful tool for the quality evaluation of hake fillets.

Average values of irradiance on a horizontal surface are calculated using a single equation which gives the distribution of total radiation as a function of the time of day and day of year. Irradiances measured at Modena (Italy) agree with the calculated values. This general expression may be used to calculate irradiances for other locations.

Mise au point bibliographique concernant les aspects technologiques, chimiques, biochimiques, microbiologiques, organoleptiques et nutritionnels de la conservation des fraises par irradiation gamma

A steam distillation method for the determination of the TBA number in control and irradiated hake and tuna is presented. Chemical values are compared with sensoric evaluation results for the 30-day cold storage period. Close correlation has been observed between the organoleptic scores and the oxidative rancidity in tuna loins and hake fillets, whether control or irradiated.

Chemical methods and procedures for measurement of changes in freeze-stored fish are reviewed. A variety of lipid extraction methods, protein and amino acids assay procedures, trimethylamine production and enzymatic activity evaluation are discussed. With chemical methods only it would be impossible to determine whether a sample had changed or not. Parallel chemical and sensory methods are suggested for quality evaluation.

TBA numbers of irradiated and control tuna samples reached a maximum after 25 and 10 days of cold storage, respectively. A decline occurred thereafter for both samples. These changes may be correlated with sensory acceptability scores.

The content of 16 essential elements was determined in fresh strawberry fruit, irradiated strawberries and strawberry marmalade. The elemental composition of fresh strawberries was compared with that of irradiated berries and strawberry marmalade. There were significantly higher amounts of sodium, chloride, calcium, iron, cobalt, nickel, copper, zinc and tin in the marmalade than in the fresh and irradiated fruit. Significantly lower amounts of potassium were observed in the strawberry marmalade than in fresh and irradiated berries. No significant differences in magnesium, silicon, phosphorus, manganese and molybdenum were found between control and irradiated fruits and marmalade. No significant differences were observed between the elemental composition of control and irradiated strawberry fruit.

Dose distribution in a 60Co irradiation unit has been calculated. Some aspects of the radiation field within the irradiation chamber for which there is no information available were considered. The dose rate was measured by means of Fricke and Ferrous-Cupric dosimetry. Isodose curves distribution and results of comparison between dose measurement and calculation are presented.

An underwater dose rate evaluation method for 60 Co linear sources is presented. It will permit better design of pool irradiation facilities. An additional simplification for γ-irradiation in air is also presented in this paper.

Photopeak and random sum peak due to monoenergetic γ-rays from 203 Hg, 54 Mn, 51 Cr and 137 Cs can be used to determine the resolving time of resolving time of NaI(TI) scintillation detectors. The method, which proved to be simple and reliable, is described.