Neutron spectrometer for fast nuclear reactors

In this paper we describe the development and first tests of a neutron spectrometer designed for high flux environments, such as the ones found in fast nuclear reactors. The spectrometer is based on the conversion of neutrons impinging on $^6$Li into $\alpha$ and $t$ whose total energy comprises the initial neutron energy and the reaction $Q$-value. The $^6$LiF layer is sandwiched between two CVD diamond detectors, which measure the two reaction products in coincidence. The spectrometer was calibrated at two neutron energies in well known thermal and 3 MeV neutron fluxes. The measured neutron detection efficiency varies from 4.2$\times 10^{-4}$ to 3.5$\times 10^{-8}$ for thermal and 3 MeV neutrons, respectively. These values are in agreement with Geant4 simulations and close to simple estimates based on the knowledge of the $^6$Li(n,$\alpha$)$t$ cross section. The energy resolution of the spectrometer was found to be better than 100 keV when using 5 m cables between the detector and the preamplifiers.Comment: submitted to NI

New infrastructure for studies of transmutation and fast systems concepts

In this work we report initial studies on a low power Accelerator-Driven System as a possible experimental facility for the measurement of relevant integral nuclear quantities. In particular, we performed Monte Carlo simulations of minor actinides and fission products irradiation and estimated the fission rate within fission chambers in the reactor core and the reflector, in order to evaluate the transmutation rates and the measurement sensitivity. We also performed a photo-peak analysis of available experimental data from a research reactor, in order to estimate the expected sensitivity of this analysis method on the irradiation of samples in the ADS considered

Study of uranium solubility in gallium-indium eutectic alloy by emf method

Activity, activity coefficients and solubility of uranium in Ga-In eutectic alloy as well as activity of uranium in U-Ga and U-In alloys were determined between 573 and 1073 K using electromotive force (emf) method. © 2013 Pleiades Publishing, Ltd

Thermodynamics of reaction of praseodymium with gallium-indium eutectic alloy

Thermodynamic properties of Ga-In eutectic alloys saturated with praseodymium were determined for the first time employing the electromotive force method. The equilibrium potentials of the Pr-In alloys saturated with praseodymium (8.7-12.1 mol.% Pr) and Pr-Ga-In alloys (containing 0.0012-6.71 mol.% Pr) were measured between 573-1073 K. Pr-In alloy containing solid PrIn3 with known thermodynamic properties was used as the reference electrode when measuring the potentials of ternary Pr-In-Ga alloys. Activity, partial and excessive thermodynamic functions of praseodymium in alloys with indium and Ga-In eutectic were calculated. Activity (a), activity coefficients (γ) and solubility (X) of praseodymium in the studied temperature range can be expressed by the following equations: lgaα-Pr(In) = 4.425 - 11965/T ± 0.026. lgα-Pr(Ga-In) = 5.866 - 14766/T ± 0.190. lgγα-Pr(Ga-In) = 2.351 - 9996/T ± 0.39. lgPr(Ga-In) = 3.515 - 4770/T ± 0.20. © 2013 Elsevier B.V. All rights reserved

Issues of diagnostics and treatment of abdominal pain at irritable bowel syndrome at outpatient stage of the healthcare

The aim of review. To present the diagnostic and treatment algorithm for abdominal pain at out-patient/ polyclinic healthcare institutions and to demonstrate potential of hyoscine butylbromide application during diagnostic process and for relief of abdominal pain at irritable bowel syndrome.Summary. From 20% to 50% of all admissions to medical institutions are related to abdominal spasms and pain caused by irritable bowel syndrome (IBS). According to the Clinical guidelines of the Russian gastroenterological association and abdominal pain management algorithm at outpatient reception, the doctor on the basis of interviewing, inspection and physical data first of all should exclude acute abdominal diseases (acute pain, parietal pain) requiring urgent examination by the surgeon or gynecologist and subsequent hospitalization. In the case of visceral pain the minimal range of laboratory and instrumental tests is indicated. If the history of visceral pain is more than 6 months and there are no alarm symptoms, doctor should define specific features of clinical presentation already during outpatient visit, taking into account pain location, that provides formulation of preliminary diagnosis. Epigastric pain (dyspepsia), biliary pain, abdominal pain which can be accompanied by impaired frequency and consistency of stool determine the further investigation plan. Implementation of diagnostic algorithm allows to distinguish the organic disease or to establishthe diagnosis of functional disease. Hyoscine butylbromide at short-term treatment will relieve abdominal spasm as a symptomatic agent. Course treatment effectively reduces intensity and frequency of abdominal pain at IBS. The rate of adverse events and tolerability of hyoscine butylbromide are comparable to that of placebo.Conclusion. Symptomatic treatment by antispasmodic drugs is justified from the moment of referral for medical aid to outpatient department. Hyoscine butylbromide can be prescribed for relief of acute and chronic pain at any stage of diagnostic process. Course intake of antispasmodics has proved its efficacy for pain relief at IBS

Excessive thermodynamic properties of praseodymium in a gallium-indium alloy

The equilibrium potentials of praseodymium-diluted homogeneous Pr-Ga-In alloys in a (Li-K-Cs)Cleut-based salt electrolyte were measured between 573-1073 K by the emf method. These potentials are used to calculate the activity coefficients of α-praseodymium in liquid Ga-In eutectic alloys. PrIn3 alloy with well-known thermodynamic characteristics and without phase transitions in the temperature range 428-1483 K was employed as the reference electrode. © 2013 Pleiades Publishing, Ltd

Thermodynamic properties of lanthanum in gallium-indium eutectic based alloys

Activity and activity coefficients of lanthanum were determined for the first time in gallium-indium eutectic based alloys in a wide temperature range employing electromotive force method. Activity of β-La and super cooled liquid lanthanum in Ga-In eutectic based alloys between 573 and 1073 K linearly depends on the reciprocal temperature: lgaβ-La(Ga-In)=5.660-15, 352T±0.093 lgaLa(Ga-In)=6.074-15,839T±0.093 Activity coefficients of β-La and super cooled liquid lanthanum in this system at 617-1073 K are described by the following equations: lgγβ-La (Ga-In)=3.786-12,216T±0.171 lgγLa(Ga-In)=4. 199-12,703T±0.171 In addition activity of lanthanum in alloys with In was also determined in the same temperature range. © 2012 Elsevier B.V. All rights reserved

Hemochromatosis - modern condition of the problem

The iron overload syndrome can be associated with various acquired states and hereditary factors. Hereditary hemochromatosis is the most common genetic disorder. Without therapeutic intervention the disease can lead to the development of life-threatening complications such as cirrhosis, hepatocellular carcinoma. The article presents data on pathogenesis, diagnosis and treatment of hereditary hemochromatosis. Own clinical observation is given

Thermodynamic properties of uranium in Ga-In based alloys

Activity of uranium was determined in gallium, indium and gallium-indium eutectic (21.8 wt.% In) based alloys between 573 and 1073 K employing the electromotive force method. In two-phase U-Ga-In alloys, uranium forms the intermetallic compound UGa3. Activity coefficients and solubility of uranium in Ga-In eutectic were also determined in the same temperature range. Partial thermodynamic functions of γ-U in saturated alloys with gallium, indium and Ga-In eutectic were calculated. © 2013 Elsevier B.V. All rights reserved

The HPS electromagnetic calorimeter

The Heavy Photon Search experiment (HPS) is searching for a new gauge boson, the so-called “heavy photon.” Through its kinetic mixing with the Standard Model photon, this particle could decay into an electron-positron pair. It would then be detectable as a narrow peak in the invariant mass spectrum of such pairs, or, depending on its lifetime, by a decay downstream of the production target. The HPS experiment is installed in Hall-B of Jefferson Lab. This article presents the design and performance of one of the two detectors of the experiment, the electromagnetic calorimeter, during the runs performed in 2015–2016. The calorimeter's main purpose is to provide a fast trigger and reduce the copious background from electromagnetic processes through matching with a tracking detector. The detector is a homogeneous calorimeter, made of 442 lead-tungstate (PbWO4) scintillating crystals, each read out by an avalanche photodiode coupled to a custom trans-impedance amplifier