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University-industry collaboration (UIC) is increasingly seen as an important driver of economic growth, but knowledge on its implementation mechanisms is still limited especially in developing countries. This constrains the capacity of those countries to design adequate policies and strategies to foster such interactions. This paper provides information about the extent to which academic staff from Tertiary Education Institutions (TEIs) in Rwanda interact with industry. It identifies the factors underlying their propensity to engage in interactions and the barriers or challenges faced. Data were collected from 334 academic staff permanently employed by 17 Higher Education Institutions in Rwanda. Results indicate a low level of interaction except in some informal channels arguably less inclined to foster relational learning and knowledge creation. Regression analyses indicated that the type of institution and the academic grades are significantly associated with the propensity of academic staff to interact with industry. In addition, four main barriers to interaction are identified and they are all linked to poor support from the government and the universities. Therefore, the study recommends the elaboration of explicit policies and strategies at country and institutional levels to set the stage for such indispensable interactions.

Movable electrical probes were used to diagnose the beam flux profile and potential of ion beams since the early 1960s. Experimental measurements of beam plasmas can provide essential data related to the space charge neutralization, but the current–voltage characteristics obtained from such electrical probes are dominated by beam ion impact and ion-induced secondary emission. In this work, we present an analysis of the Langmuir characteristics obtained in a negative ion beam. We identify and discuss separately the contributions to the collected current given by secondary plasma ions and electrons, stripped electrons, beam ions, and ion-induced secondary electron emission. We present the beam plasma parameters obtained at different beam energies in NIO1.Movable electrical probes were used to diagnose the beam flux profile and potential of ion beams since the early 1960s. Experimental measurements of beam plasmas can provide essential data related to the space charge neutralization, but the current–voltage characteristics obtained from such electrical probes are dominated by beam ion impact and ion-induced secondary emission. In this work, we present an analysis of the Langmuir characteristics obtained in a negative ion beam. We identify and discuss separately the contributions to the collected current given by secondary plasma ions and electrons, stripped electrons, beam ions, and ion-induced secondary electron emission. We present the beam plasma parameters obtained at different beam energies in NIO1.

The article describes a new method of organosilicon compounds activation by low energy electron beam for SiCN coatings deposition. The composition of the beam plasma in a hexamethyldisilazane-containing gas medium was studied, and it was shown that the precursor molecules decomposition degree increases with the beam current and nonmonotonically depends on the electron beam energy. The application of a low-energy electron beam for the plasma-chemical vapor decomposition of hexamethyldisilazane and for samples heating up by electron beam to 600°C makes it possible to obtain SiCN-based coatings with a hardness up to 18 GPa and thickness ~1 μm for 1 h. © 2020 The Japan Society of Vacuum and Surface Science. All rights reserved. The study was financially supported by the Russian Science Fund, grant No. 18-79-00233.

International audience; An ultrafast x-ray powder diffraction setup for laser-driven dynamic compression has been developed at the LULI2000 laser facility. X-ray diffraction is performed in reflection geometry from a quasi-monochromatic laser-generated plasma x-ray source. In comparison to a transmission geometry setup, this configuration allows us to probe only a small portion of the compressed sample, as well as to shield the detectors against the x-rays generated by the laser-plasma interaction on the front side of the target. Thus, this new platform facilitates probing of spatially and temporarily uniform thermodynamic conditions and enables us to study samples of a large range of atomic numbers, thicknesses, and compression dynamics. As a proof-of-concept, we report direct structural measurements of the bcc-hcp transition both in shock and ramp-compressed polycrystalline iron with diffraction signals recorded between 2θ ∼30° and ∼150°. In parallel, the pressure and temperature history of probed samples is measured by rear-side visible diagnostics (velocimetry and pyrometry).

SEYDAOGLU, MUAZ/0000-0003-3211-0864; Kocak, Huseyin/0000-0001-9683-6096; Erdogan, Utku/0000-0003-0089-0114 This study focuses on symplectic integrators for numerical evaluation of the asymptotic solutions of the nonlinear Airy-type equations obtained by reducing the nonlinear dispersive equations. Since the nature of Airy-type equations has both highly oscillatory slow decay and exponential fast decay, most of classical integrators are not able to correctly exhibit challenging physical behaviour. We use specially designed symplectic integrators combining splitting methods with Magnus integrators to catch asymptotic behaviour of nonlinear Airy-type equations efficiently, even for large step sizes. Efficiency of the proposed methods for given problems is discussed. Moreover, numerical results obtained by the proposed methods are compared with the existing results in the literature. (C) 2020 Elsevier B.V. All rights reserved.

Wetlands are often vital physical and social components of a country’s natural capital, as well as providers of ecosystem services to local and national communities. We performed a network analysis to prioritize Sustainable Development Goal (SDG) targets for sustainable development in iconic wetlands and wetlandscapes around the world. The analysis was based on the information and perceptions on 45 wetlandscapes worldwide by 49 wetland researchers of the Global Wetland Ecohydrological Network (GWEN). We identified three 2030 Agenda targets of high priority across the wetlandscapes needed to achieve sustainable development: Target 6.3—“Improve water quality”, 2.4—“Sustainable food production”, and 12.2—“Sustainable management of resources”. Moreover, we found specific feedback mechanisms and synergies between SDG targets in the context of wetlands. The most consistent reinforcing interactions were the influence of Target 12.2 on 8.4—“Efficient resource consumption”, and that of Target 6.3 on 12.2. The wetlandscapes could be differentiated in four bundles of distinctive priority SDG-targets: “Basic human needs”, “Sustainable tourism”, “Environmental impact in urban wetlands”, and “Improving and conserving environment”. In general, we find that the SDG groups, targets, and interactions stress that maintaining good water quality and a “wise use” of wetlandscapes are vital to attaining sustainable development within these sensitive ecosystems.

The research concerned the possibility of using the microplasma welding technique for joining thin titanium alloy Grade 5 (6Al-4V) sheets. For this purpose, titanium reference samples without welds (Type 1) and two types of welded joints (butt joint - Type 2 and Type 3 overlap joint) were made with selected microplasma welding parameters for which strength parameters were determined and compared with the strength of the native material. The assessment of the connection quality was made on the basis of a monotonic tensile test. A metallographic analysis of the welded joints was made and the breakthroughs sample obtained during the tests was also carried out. In addition, strain distributions were determined in loaded sample types, which allowed investigating the impact of the heat affected zone size on the strength of welded joints subjected to monotonic tensile tests and Vickers hardness tests. Microplasma welded joints displayed relatively high brittleness. The failure locations are still influenced by heat affected zone despite the highly concentrated plasma beam of the microplasma arc welding. © 2018 Elsevier Ltd

Hypothesis We compare the effects of water, either intentionally added or due to absorption from the air, on the phase diagram of the hydrophilic 1-butyl-3-methylimidazolium dicyanamide ionic liquid, extending previous investigations to lower temperatures (down to 140 K), with a special attention to the changes of the environment of water molecules and the interface between water and ionic liquid as a function of temperature. Experiments Combined infrared spectroscopy and ab-initio calculations provide information about the phase transitions and the intermolecular changes occurring in the liquid. Findings The temperature dependence of the mid-infrared spectrum in the temperature range between 140 and 330 K indicates that in both cases the liquid undergoes a glass transition, but, when the water content is only due to absorption from air, a cold crystallization takes place on heating between ≈240 and ≈265 K, while it is suppressed when water is intentionally added in a greater amount. The analysis of the O H stretching bands indicates the existence of two different “liquid like” water environments. When cold crystallization takes places the water molecules, which seem less coordinated to the other H2O molecules and more related to the anions, appear to be part of the crystallized sample. In both cases, it seems that at microscopic level the sample is not homogeneous, but more likely it is composed of separated clusters or regions of bulk water confined in the ionic liquid.

This paper presents the experimental characterization of a spray produced by a VVER-440 nuclear reactor type nozzle. Several droplet size and velocity profiles have been obtained at different pressure supplies and different heights below the outlet of the spray nozzle. Repeatability and stability have been checked. A log-normal size distribution can be fitted on the experimental results. Correlations between droplet velocities and sizes at different locations are also given, showing that for small droplet sizes (below 300 μm) no clear size-velocity correlation exists below 0.7 m from nozzle outlet, but for larger droplets, a classical evolution of this correlation is observed. It is concluded that the experimental data obtained at 300 mm from the nozzle outlet can be used as spray boundary conditions for numerical calculations with CFD codes. The other experimental data (at 500 and 700 mm from the nozzle outlet) can serve for detailed code validation, if the correlations between sizes and velocities are considered in the validation procedure: indeed, the averaging of droplet sizes and velocities can mask some typical spray results on droplet sizes and velocities evolutions. If a good code validation of the size-velocity correlations is obtained at 500 and 700 mm from the nozzle outlet, the concerned code may then be used with good confidence to extrapolate the results at other distances (for example, 3 m, 5 m) which cannot be obtained easily experimentally. © 2016 by Begell House, Inc.

In the case of a hypothetical severe accident in a Pressurized Water Reactor (PWR), Silver-Indium-Cadmium (SIC) control rod failure occurs early during the sequence. Release of absorber melt could induce early fuel rod degradation by interaction of molten SIC alloy with fuel rod cladding, and the absorber materials could interact with the fission products, affecting significantly their speciation and transport in the primary circuit as well as their behaviour in the containment. This paper summarises the experimental and modelling progress made on this topic within SARNET over the whole project. Following a review of the status of knowledge, including the modelling in the main severe accident codes (ATHLET-CD, MAAP4, SCDAP, MELCOR, ASTEC), detailed calculations of the specific EMAIC and integral PHEBUS FPT2 experiments were performed. Accurate calculation of vapour pressure of the molten absorber elements is needed, requiring reliable values of the activity coefficients. The importance of accurate reproduction of the control rod degradation was shown, with the behaviour of absorber elements at rupture being critical as well as the thermodynamic data and speciation of the system Ag-In-Cd-Zr-H-O. The QUENCH-13 bundle experiment (FZK), conducted with a realistic integral geometry composed of 20 electrical heated rod simulators and one central SIC absorber rod, has helped to characterize the behaviour of absorber elements at the time of rod rupture, with measurements of the SIC release, using impactors (AEKI) and electrical low-pressure impactor and Berner low-pressure impactors (PSI). Coordinated pre and post-test calculations using SCDAP/RELAP5 based codes (PSI), MAAP4 (EDF), ATHLET-CD (GRS), ASTEC (IRSN) helped in defining the test and in its interpretation. Before this experiment, five tests were performed on small-scale SIC control rod samples using different designs and conditions. They helped in defining the conditions for the QUENCH-13 experiment. Five additional tests on similar small-scale samples are foreseen to help interpretation of the QUENCH-13 results. In QUENCH-13 the on-line aerosol measurements with electrical low-pressure impactors indicated control rod failure in the range 1550-1600 K; the test was terminated later at 1813 K by water reflood. Analysis of aerosols measured at sample points in the off-gas line showed significant Cd and In transport after rod failure with a smaller amount of transported Ag. Relocated SIC melt in the form of rivulets was detected in the lower part of the bundle. Investigation of SIC material properties (solidus, liquidus) by further analysis of data from QUENCH-13 is also presented. In parallel, an exhaustive review of activity coefficients of the elements in the SIC melt, including the effect of Zr was began (IRSN with the CNRS Marseille). © 2009 Elsevier Ltd. All rights reserved.

An experiment was performed using the PALS laser to study laser-target coupling and laser-plasma interaction in an intensity regime ≤1016 W/cm2, relevant for the "shock ignition" approach to Inertial Confinement Fusion. A first beam at low intensity was used to create an extended preformed plasma, and a second one to create a strong shock. Pressures up to 90 Megabars were inferred. Our results show the importance of the details of energy transport in the overdense region. © 2014 AIP Publishing LLC.

International audience; During the course of a severe accident in a Nuclear Power Plant, water can be collected in the sump containment through steam condensation on walls and spray systems activation. The objective of this paper is to present code validation on evaporative sump tests performed on TOSQAN facility. The ASTEC-CPA code is used as a lumped-parameter code and specific user-defined-functions are developed for the TONUS-CFD code. The seven tests are air-steam tests, as well as tests with other non-condensable gases (He, CO2 and SF 6) under steady and transient conditions (two depressurization tests). The results show a good agreement between codes and experiments, indicating a good behavior of the sump models in both codes. The sump model developed as User-Defined Functions (UDF) for TONUS is considered as well validated and is 'ready-to-use' for all CFD codes in which such UDF can be added. The remaining discrepancies between codes and experiments are caused by turbulent transport and gas mixing, especially in the presence of non-condensable gases other than air, so that code validation on this important topic for hydrogen safety analysis is still recommended. © 2013 Elsevier B.V. All rights reserved.

We present X-ray spectroscopic diagnostics in femto-second laser-driven experiments revealing nonlinear phenomena caused by the strong coupling of the laser radiation with the created plasma. Among those nonlinear phenomena, we found the signatures of the Two Plasmon Decay (TPD) instability in a laser-driven CO2 cluster-based plasma by analyzing the Langmuir dips in the profile of the O VIII Lyϵ line, caused by the Langmuir waves created at the high laser intensity 3 1018Wcm-2. With similar laser intensities, we reveal also the nonlinear phenomenon of the Second Harmonic Generation (SHG) of the laser frequency by analyzing the nonlinear phenomenon of satellites of Lyman δ and ϵ lines of Ar XVII. In the case of relativistic laser-plasma interaction we discovered the Parametric Decay Instability (PDI)-induced ion acoustic turbulence produced simultaneously with Langmuir waves via irradiation of thin Si foils by laser intensities of 1021Wcm-2.

In high power neutral beams for fusion, beam uniformity is an important figure of merit. Knowing the transverse power profile is essential during the initial phases of beam source operation, such as those expected for the ITER heating neutral beam (HNB) test facility. To measure it a diagnostic technique is proposed, based on the collection of secondary electrons generated by beam-surface and beam-gas interactions, by an array of positively biased collectors placed behind the calorimeter tubes. This measurement showed in the IREK test stand good proportionality to the primary beam current. To investigate the diagnostic performances in different conditions, we developed a numerical model of secondary electron emission, induced by beam particle impact on the copper tubes, and reproducing the cascade of secondary emission caused by successive electron impacts. The model is first validated against IREK measurements. It is then applied to the HNB case, to assess the locality of the measurement, the proportionality to the beam current density, and the influence of beam plasma.

In vivo measurements are usually carried out under the hypothesis of a known activity distribution inside the body. The measurements and the interpretation of in vivo measurements performed with the minimum hypothesis about the activity distribution are presented and discussed. Measurements have been performed with a devoted four-germanium-detector system on a male subject presenting a 30-yr-old wound contamination by ameri- cium and plutonium isotopes. The measurements have been processed after the construction of voxelized phantoms of the measured body parts and Monte Carlo (MC) calculations of organ- and detector-specific counting efficiencies. The phantom construction and MC calculaHons were assisted by the OEDIPE software, and the reliability of the modeling has been controlled by a comparison of the measured and simulated efficiencies for point-source measurements and for the measurement of a Spitz anthropomorphic knee phantom. Mainly based on measurements at the knee level, the 241 Am specific bone activity was (0.27 ± 23%) Bq/g. Using measurements at the thorax level, no activity could be detected in the lungs; the liver activity was between 410 and 460 Bq. The activity of the axillary, thoracic airways and trunk lymph nodes depends on the retained hypothesis, but a reasonable assessment for the axillary lymph nodes is between 100 and 350 Bq.

CVD mono-crystalline diamond thin films deposited on a doped diamond and aluminum backing were employed as detectors of the radiation emitted from the laser-generated plasma. Laser-matter interactions were obtained by the use of an Nd:Yag repetitive laser at INFN-LNS in Catania operating at 1010 W/cm2 pulse intensity, and a high-power iodine PALS laser in Prague operating at 1015 W/cm2 pulse intensity. Plasmas were obtained by ablating Al, Ta, Au, and CF2 bulk targets. Plasma characterization was carried out using diamond detectors and ion collectors placed at different distances and angles in relation to the position of the ablated target. Photons, electrons, and ions hitting the sensible volume of the detector generate electronhole pairs (loosing 13 eV for a pair), resulting in an arising of the voltage signal at the device electrodes, which is proportional to the deposited energy. Diamond detectors can measure UV, X-rays, electrons, and ions. The time-of-flight (TOF) technique was exploited to separate...

This article presents the main results of the Persistent Scatterer Interferometry Codes Cross Comparison and Certification for long term differential interferometry (PSIC4) project. The project was based on the validation of the PSI (Persistent Scatterer Interferometry) data with respect to levelling data on a subsiding mining area near Gardanne, in the South of France. Eight PSI participant teams processed the SAR data without any a priori information, as a blind test. Intercomparison of the different teams' results was then carried out in order to assess any similarities and discrepancies. The subsidence velocity intercomparison results obtained from the PSI data showed a standard deviation between 0.6 and 1.9 mm/year between the teams. The velocity validation against rates measured on the ground showed a standard deviation between 5 and 7 mm/year. A comparison of the PSI time series and levelling time series shows that if the displacement is larger than about 2 cm in between two consecutive SAR-images, PS-InSAR starts to seriously deviate from the levelling time series. Non-linear deformation rates up to several cm/year appear to be the main reason for these reduced performances, as no prior information was used to adjust the processing parameters. Under such testing conditions and without good ground-truth information, the phase-unwrapping errors for this type of work are a major issue. This point illustrates the importance of having ground truth information and a strong interaction with the end-user of the data, in order to properly understand the type and speed of the deformation that is to be measured, and thus determine the applicability of the technique. © 2009 Elsevier B.V. All rights reserved.

This article presents the main results of the Persistent Scatterer Interferometry Codes Cross Comparison and Certification for long term differential interferometry (PSIC4) project. The project was based on the validation of the PSI (Persistent Scatterer Interferometry) data with respect to levelling data on a subsiding mining area near Gardanne, in the South of France. Eight PSI participant teams processed the SAR data without any a priori information, as a blind test. Intercomparison of the different teams' results was then carried out in order to assess any similarities and discrepancies. The subsidence velocity intercomparison results obtained from the PSI data showed a standard deviation between 0.6 and 1.9 mm/year between the teams. The velocity validation against rates measured on the ground showed a standard deviation between 5 and 7 mm/year. A comparison of the PSI time series and levelling time series shows that if the displacement is larger than about 2 cm in between two consecutive SAR-images, PS-InSAR starts to seriously deviate from the levelling time series. Non-linear deformation rates up to several cm/year appear to be the main reason for these reduced performances, as no prior information was used to adjust the processing parameters. Under such testing conditions and without good ground-truth information, the phase-unwrapping errors for this type of work are a major issue. This point illustrates the importance of having ground truth information and a strong interaction with the end-user of the data, in order to properly understand the type and speed of the deformation that is to be measured, and thus determine the applicability of the technique. © 2009 Elsevier B.V. All rights reserved.