145 research outputs found

    Traces of Radioactive I-131 in Rain Water and Milk Samples in Romania

    Full text link
    Measurements of I-131 (T1/2 = 8.04 days) have been performed in IFIN-HH's underground laboratory situated in Unirea salt mine from Slanic-Prahova, Romania. The rain water samples were collected in March 27th in Brasov and in March 27th, 29th and April 2nd in Slanic. Also sheep milk was collected in Slanic area and subsequently measured. The samples were measured in the IFIN-HH's underground laboratory in ultra-low radiation background, using a high resolution gamma-ray spectrometer equipped with a GeHP detector having a FWHM = 1.80 keV at 1332.48 keV at the second Co-60 gamma-ray, and a relative efficiency of 22.8%. The results show a specific activity of I-131 from 0.17 to 0.87 Bq/dm^3. In the sheep milk from Slanic area the specific activity of I-131 was about 6 Bq/dm^

    In vivo real-time recording of UV-induced changes in the autofluorescence of a melanin-containing fungus using a micro-spectrofluorimeter and a low-cost webcam.

    Get PDF
    An optical epifluorescence microscope, coupled to a CCD camera, a standard webcam and a microspectrofluorimeter, are used to record in vivo real-time changes in the autofluorescence of spores and hyphae in Aspergillus niger, a fungus containing melanin, while exposed to UV irradiation. The results point out major changes in both signal intensity and the spectral shape of the autofluorescence signal after only few minutes of exposure, and can contribute to the interpretation of data obtained with other fluorescence techniques, including those, such as GPF labeling, in which endogenous fluorophores constitute a major disturbance

    Temporal variation of surface chlorophyll a in the Romanian near-shore waters

    Get PDF
    Chlorophyll a (Chl a) dynamics in the near-shore waters of the NW Black Sea was investigated between 2002 and 2010 in the Mamaia Bay (north of Constanta, Romania) in relation to some physical-chemical parameters. Chl a ranged from values below detection limit (0.17 μg.l–1) to 76.13 μg.l–1, and showed large temporal variability (CV = 142.3%), strongly related to the Danube’s discharges, meteorological conditions, and anthropogenic pressures. Seasonally, Chl a showed a winter/early spring maximum, sometimes followed by a stronger one in April/early May, closely linked to the Danube’s higher discharges in spring. After significantly lower concentrations in late spring/early summer, Chl a exhibited its strongest maximum in summer (July-August), followed by another one in autumn (late September–October). Interannual variation of Chl a seems to be controlled by the hydrometeorological conditions in summer. Thus, the highest annual Chl a means were observed in 2006 (8.56 ± 8.35 μg.l–1) and 2010 (9.20 ± 11.72 μg.l -1), when, also, the summer Chl a concentrations were maximal due to the large riverine discharges. The lowest annual Chl a mean was observed in 2004 (4.57 ± 9.81μg.l–1), closely linked to minimal summer Chl a resulted from a strong P limitation during summertime

    Use of stable isotope signatures (δ13C & δ15N) in the Black Sea Danubian area – new approach for understanding the influence of terrestrial discharge upon the marine ecosystem

    Get PDF
    Abstract. Coastal marine zones located in front of large rivers are of major biological interest. In these areas, the origin of the organic matter is complex and highly variable. The continental inputs, added to the nutrients already present in the marine environment, influence considerably the productivity and functioning of the ecosystems. Used for the first time in aquatic ecology on the Romanian coast, the proportion of stable isotopes of carbon (13C/12C) and nitrogen (15N/14N) allowed the identification of the organic material sources (terrestrial and marine) as well as the analysis of the food webs due to the predictable isotopic relation between consumers and their food. Preliminary analyses of stable isotopes of the particulate organic matter POM of the Danube water as well as marine POM, sediments and marine organisms were made on 186 samples collected at 10 stations in October 2004. The identification of the isotopic signatures of the main sources of organic material (terrestrial and marine) was achieved along with those of some groups of marine organisms present in this area (macrophytes, bivalves, polychaetes, amphipods, macrurans, brachyurans and fish). The results obtained in the Black Sea were compared with those of the Mediterranean Sea seawards the Rhone river and showed that the isotopic signatures of the two river POM were close to each other, whereas they largely differed in marine phytoplankton and macrophytes

    A mobile detector for measurements of the atmospheric muon flux in underground sites

    Full text link
    Muons comprise an important contribution of the natural radiation dose in air (approx. 30 nSv/h of a total dose rate of 65-130 nSv/h), as well as in underground sites even when the flux and relative contribution are significantly reduced. The flux of the muons observed in underground can be used as an estimator for the depth in mwe (meter water equivalent) of the underground site. The water equivalent depth is an important information to devise physics experiments feasible for a specific site. A mobile detector for performing measurements of the muon's flux was developed in IFIN-HH, Bucharest. Consisting of 2 scintillator plates (approx. 0.9 m2) which measure in coincidence, the detector is installed on a van which facilitates measurements at different locations at surface or underground. The detector was used to determine muon fluxes at different sites in Romania. In particular, data were taken and the values of meter water equivalents were assessed for several locations from the salt mine from Slanic Prahova, Romania. The measurements have been performed in 2 different galleries of the Slanic mine at different depths. In order to test the stability of the method, also measure- ments of the muon flux at surface at different elevations were performed. The results were compared with predictions of Monte-Carlo simulations using the CORSIKA and MUSIC codes

    Understanding and supporting law enforcement professionals working with distressing material: Findings from a qualitative study

    Get PDF
    This study aimed to extend previous research on the experiences and factors that impact law enforcement personnel when working with distressing materials such as child sexual abuse content. A sample of 22 law enforcement personnel working within one law enforcement organisation in England, United Kingdom participated in anonymous semi-structured interviews. Results were explored thematically and organised in the following headings: “Responses to the material”, “Impact of working with distressing evidence”, “Personal coping strategies” and “Risks and mitigating factors”. Law enforcement professionals experienced heightened affective responses to personally relevant material, depictions of violence, victims’ displays of emotions, norm violations and to various mediums. These responses dampened over time due to desensitisation. The stress experienced from exposure to the material sometimes led to psychological symptoms associated with Secondary Traumatic Stress. Job satisfaction, self-care activities, the coping strategies used when viewing evidence, detachment from work outside working hours, social support and reducing exposure to the material were found to mediate law enforcement professionals’ resilience. Exposure to distressing material and the risks associated with this exposure were also influenced by specific organisational procedures implemented as a function of the funding available and workload. Recommendations for individual and organisational practices to foster resilience emerged from this research. These recommendations are relevant to all organisations where employees are required to view distressing content

    The LBNO long-baseline oscillation sensitivities with two conventional neutrino beams at different baselines

    Get PDF
    The proposed Long Baseline Neutrino Observatory (LBNO) initially consists of 20\sim 20 kton liquid double phase TPC complemented by a magnetised iron calorimeter, to be installed at the Pyh\"asalmi mine, at a distance of 2300 km from CERN. The conventional neutrino beam is produced by 400 GeV protons accelerated at the SPS accelerator delivering 700 kW of power. The long baseline provides a unique opportunity to study neutrino flavour oscillations over their 1st and 2nd oscillation maxima exploring the L/EL/E behaviour, and distinguishing effects arising from δCP\delta_{CP} and matter. In this paper we show how this comprehensive physics case can be further enhanced and complemented if a neutrino beam produced at the Protvino IHEP accelerator complex, at a distance of 1160 km, and with modest power of 450 kW is aimed towards the same far detectors. We show that the coupling of two independent sub-MW conventional neutrino and antineutrino beams at different baselines from CERN and Protvino will allow to measure CP violation in the leptonic sector at a confidence level of at least 3σ3\sigma for 50\% of the true values of δCP\delta_{CP} with a 20 kton detector. With a far detector of 70 kton, the combination allows a 3σ3\sigma sensitivity for 75\% of the true values of δCP\delta_{CP} after 10 years of running. Running two independent neutrino beams, each at a power below 1 MW, is more within today's state of the art than the long-term operation of a new single high-energy multi-MW facility, which has several technical challenges and will likely require a learning curve.Comment: 21 pages, 12 figure
    corecore