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Recently, the formation of the ceramic-ionic liquid composite has attracted huge interest in the scientific community. In this work, we investigated the chemical reactions occurring between NASICON LAGP ceramic electrolyte and ionic liquid pyr13TFSI. This study allowed us to identify the cation exchange reaction pyr13-Li occurring on the LAGP surface, forming a LiTFSI salt that was detected by the nuclear magnetic resonance analysis. In addition, using 6 Li foils, we succeeded in demonstrating that both LAGP and LiTFSI:pyr13TFSI participate in the diffusion of Li ions by the formation of an ionic bridge between two species.

The purpose of this master’s thesis was to examine how decision-making on risks is perceived in the target multi-actor network, what are the challenges and enablers experienced, and how risk-informed and risk-related decision-making could be developed. The study aimed to enhance the understanding of decision-making regarding risks in complex network environments that involve multiple actors and interfaces in the diverse context of risk management. The research design was based on a single-case study implemented in a multi-national project organization. The data collection method was a thematic interview, and the data gathered was analyzed by conducting a thematic analysis. The challenges of the decision-making process with respect to risks were considered to derive both from the intricate network environment and individual factors. Even though the multi-actor network was perceived to bring complexity into the decision-making process, the 360-degree environment was described as including several benefits, such as increased competences and valuable experience to be shared. In addition, the multi-actor network was said to provide alternative routes for managing complicated decision-making situations with its numerous channels. However, the higher the number of actors involved, the more conflicts of interest may emerge, and differing risk perceptions and preferences join the game. Even though the multi-actor network may give a rise to the external factors of bounded rationality, the impact of bounded rationality caused by the internal factors might be decreased. Several recommendations were created based on the perceptions of the interviewees to tackle the challenges perceived, enhance the enablers and benefits involved, and develop the risk decision-making process at large. Firstly, the risk management culture should be improved via various measures, such as joint planning, training, and sharing a mutual understanding of the rules, roles, and responsibilities of decision-making on risks project wide. Secondly, the effectiveness and openness in managing the information flows should be increased, covering joint risk conceptualizations and terminology. Thirdly, the effects of individual thinking and cultural dimensions on risk-informed and risk-related decision-making should be recognized and considered. Finally, despite the contractual limitations, risk management should be appraised as a joint effort which requires genuine cooperation along with respectful criticality.

Regulations concerning potential future health impacts of the final disposal of radioactive wastes in geological disposal facilities are written in terms of annual dose to individuals who are representative of small groups living in the landscape in the vicinity of the repository site. As disposal programmes in Sweden and Finland have progressed towards licensing and construction, so too has detail describing the state and evolution of surface biosphere and the landscape around the proposed disposal sites increased. Simple and generic biosphere dose assessment models in early iterations have grown in complexity with increasing site-specific detail that aims to capture the radiologically significant features of the landscape into which future releases of radionuclides might credibly occur. Current dose assessment models used in support of license applications for disposal programmes in Sweden and Finland are highly complex and their application consequently lacks transparency. An alternative simpler approach to characterising landscape objects for dose assessment models would be beneficial in that it would offer an additional line of reasoning and would add clarity, thereby supporting the decision-making process of the regulatory authorities. In the context of coastal Fennoscandia, landscape change is relatively rapid and dramatic with post-glacial landrise transforming areas of the coastal seabed into terrestrial ecosystems over a period of a few thousand years, global sea level rise notwithstanding. The locations of the geosphere-biosphere interfaces for deep geologic disposal can be estimated with some precision but the nature of the receiving ecosystems at the time of the release is less certain. The approach described here provides a statistical quantification of key morphological characteristics of areas in the landscape where doses could arise, so as to better express uncertainties in dose modelling. The proposed method assumes that the variation in the morphology of potential release locations can be described by the variation in landscape objects seen in the landscape on a wider scale, providing a statistical description of the possible landscape objects, so allowing a more comprehensive range of potential future evolutions to be addressed. Our understanding of the evolution of the landscape, based on the kinds of terrain and ecosystem development models used by POSIVA in Finland and SKB in Sweden, suggests that objects identified in present-day maps can be used as analogues for a statistical characterisation of objects in the future landscape; objects identified in the observed topography and bathymetry can therefore serve as the basis for the statistical description of landscape dose objects over the period during which doses are likely to arise. Using digital elevation models around a disposal site in Finland, we show that the statistical descriptions of landscape dose objects at three times over a period of 10 kyear of the evolved landscape are sufficiently similar to establish the suitability of the approach. The aim of this statistical analysis is to supplement current methods for defining radiological assessment models so as to provide additional numerical support to both the simpler and more complex methods employed by implementors and regulators. The method has been developed in the context of the Swedish and Finnish regulatory review process and is referred to in the IAEA's revised BIOMASS methodology. We briefly address how the method might be applied in other landscape contexts.

In this article, we prove the existence and uniqueness of a solution for 2-dimensional time-fractional differential equations with classical and integral boundary conditions. We start by writing this problem in the operator form and we choose suitable spaces and norms. Then we establish prior estimates from which we deduce the uniqueness of the strong solution. For the existence of solution for the fractional problem, we prove that the range of the operator generated by the considered problem is dense.

The existence of mild solutions of a totally nonlinear Caputo-Hadamard fractional differential equation isinvestigated using the Krasnoselskii-Burton fixed point theorem and some results are presented. Two exampleare given to illustrate our obtained results.

Cet article résume les résultats de l'étude de la variabilité spatio-temporelle du niveau moyen de la mer Méditerranée ainsi que sa représentation par les modes fondamentaux permettant une réduction des données. L’analyse de la série temporelle d’anomalies moyennes de hauteur de la mer (ou sea level anomalies-SLA), issues des mesures recueillies par les différentes missions d’altimétrie satellitaire sur la période de janvier 1993 à décembre 2015, montre une différenciation évidente Est-Ouest. Le bassin oriental a augmenté de façon très nette. Par contre, au niveau de l'Italie (mer Ionienne), le niveau a baissé. Afin de décrire les modes fondamentaux de variabilité, une décomposition du set des données en fonctions orthogonales empiriques (EOF) a été effectuée. Les fonctions calculées, tronquées à 20, permettent une réduction de l'espace des données tout en expliquant prés de 80% de la variance des données analysées. Les cartes reconstruites à partir des EOFs estimés sont en concordance avec les données sources. English title: Spatio-temporal analysis of the evolution of the Mediterranean Sea surface This paper focuses on the analysis of the spatio-temporal variability of Mediterranean sea level and its representation by fundamental modes allowing a reduction of the data. The analysis of the temporal series of sea level anomalies (SLA), derived from the measurements from various satellite altimetry missions over the period from January 1993 to December 2015 shows a differentiation obvious East-West. The Eastern basin has increased sharply. On the other hand, the sea level has decreased at the level of Italy (Ionian Sea). In order to describe the fundamental modes of Mediterranean sea level variability, a decomposition of the set of data into Empirical Orthogonal Functions (EOF) was performed. The computed functions, truncated at 20, allow a reduction of the space of the data while explaining nearly 80% of the variance of the analyzed data. The maps reconstructed from the estimated EOFs are in agreement with the original data.

International audience; The growth process and post-deposition treatment have strong effects on the structure of ZnO thin films, which can also significantly affect their electrical and piezoelectric properties. In this report, the effect of high temperature annealing under oxygen atmosphere on ZnO stacked thin films grown on silicon by pulsed-liquid injection metal-organic chemical vapor deposition is investigated in detail. By varying the annealing temperature from 600 to 1000 °C, the structural analysis reveals the occurrence of c-axis oriented grain coarsening and growth processes associated with the improvement of crystallinity and removal of carbon impurities. The electrical resistivity also strongly varies with thermal annealing. Those variations are accompanied by an enhancement of the piezoelectric amplitude measured by piezo-response force microscopy (PFM). Interestingly, the PFM measurements reveal the predominant development of O-and Zn-polar domains at low and high temperature annealing, respectively, originating from the anisotropic grain boundary velocity. The present findings show that the high temperature annealing under oxygen atmosphere in ZnO thin films can enhance not only its piezo-amplitude but also its Zn-polarity uniformity, which unambiguously leads to the improvement of its piezoelectric performance.

During the last three decades, the Mediterranean coasts have been under strong anthropogenic pressure inducing ecological and biological degradations such as pollution, destruction of marine ecosystems, and loss of coastal dunes. In Algeria, the same findings have been observed in the bay of Algiers due to the massive urbanization as well as the absence of the quantitative analysis tools of this phenomenon. In this context, the assigned objective of this study is the monitoring of the urban growth in Algiers’ bay between 1985 and 2015 and the prediction of the urban growth by 2030 using remote sensing data, cellular automata modeling, and the landscape metrics analysis. Concerning the prediction step, two scenarios are considered: the “tendencial” which presents the unmanaged urban growth of Algiers City and the active implementation of the Algiers Plan by 2029. To achieve this goal, a retrospective map representing land cover has been produced at different times; this later has allowed us to quantify the urban regions and to implement the urbanization growth model. On the other hand, this study has highlighted the contribution of the spatial metrics on multi-scale level (patch/core, class level and the landscape level) to monitor coastal urbanization in a geometric/fractal view through its multi-temporal evolution, as well as in the two predictive landscapes. This allowed through the spatial metrics indicator and predictive modeling to observe a tendency to massive urbanization of the bay at the expense of remaining natural areas, but also to provide and exhibit some geographical aspects such as the layout of urban cores and the linearity of urbanization parallel to the coast, in order to propose some significant measures for policy-makers to avoid the alarmist environmental degradation of the bay.

In this work, a non-toxic protonated kaolin clay exchanged with protons, was successfully applied as a solid acid catalyst for the polymerization of tetrahydrofuran (poly(THF)) at room temperature in the presence of acetic anhydride. Prior to using the kaolin as a catalyst, it was treated with HCl (0.1 M) and characterized using various analytical techniques. The amounts of catalyst and reaction time on the conversion of THF were investigated. Characterizations of nuclear magnetic Resonance of proton (1H-NMR), Fourier Transform Infrared spectroscopy (FT-IR), X-ray Diffraction (XRD), Optical Microscopy (OM), and Differential Scanning Calorimetry (DSC) techniques were used to examine the resulting polymer. X-ray characterization and DSC data indicated that the obtained poly(THF) is a highly crystalline substance. The results showed that protonated kaolin (kaolin–H+) has a high catalytic activity for the polymerization of THF with a conversion rate of 50.02% after 20 hours. Copyright © 2019 BCREC Group. All rights reserved.

In this work, we deposited a nanometric layer of platinum (40 nm thick) on a standard propylene/polypropylene Celgard separator 3501 by plasma sputtering, and studied the effect of this thin layer when in contact with a lithium metal anode in a Li-S battery. The platinum-coated Celgard slowed down the shuttle effect at low current density (C/10) compared to standard Celgard and led to an increase in capacity retention at higher current density (C/2). In addition, the polarization was reduced with a platinum separator in a Li-Li symmetric cell after 500 h.

We report on the synthesis of amphiphilic polymers with a composition shift of the hydrophobic block made by emulsion polymerization that is used as a water-based binder for LiFePO4 cathodes. The integrity of the electrode is sustained by using a unique chemical procedure for cross-linking the binder. This technique yields higher adhesion of the binder on aluminium collectors comparing with the state-of-the-art binders. Amphiphilic polymers are excellent for well-dispersed inorganic particles, and consequently demonstrate satisfactory electrochemical performances.

A methodology for addressing the biosphere in safety assessments for solid radioactive waste disposal was developed through theme 1 of the IAEA coordinated research project on BIOsphere Modelling and ASSessment (BIOMASS) that ran from 1996 to 2001. This methodology provided guidance on how the biosphere can be addressed in safety assessments for disposal of solid radioactive waste. Since the methodology was developed, it has proven useful and has been widely referenced in assessments in a diversity of contexts encompassing both near-surface and deep geological disposal of solid radioactive waste. The principles that could be adopted for defining potentially exposed groups (PEGs) were an important aspect in the original BIOMASS methodology as the endpoint of an assessment usually includes the evaluation of individual dose or risk to human health. Identification of PEGs and definition of their characteristics are usually made to be consistent with the biosphere system description being developed, acknowledging that due to inherent uncertainties in projecting future human behaviour, the biosphere models adopted for assessing safety of a disposal system can only be illustrative. Since the publication of the original BIOMASS methodology, consideration has been extended to include potentially exposed populations of biota (PEPs), in the context of dose assessment and protection of the environment. Considering the need for the development of transfer pathways from a source term to an end point (for either PEGs or PEPs), the exposure modes that may occur and those to be assessed quantitatively should be identified. Within an expert working group (WG6) of the second phase of the IAEA coordinated project Modelling and Data for Radiological Impact Assessments (MODARIA II), the experience of participating organisations has been collected on topics associated with the definition of PEGs and PEPs using a questionnaire. The objective of the questionnaire was to review the current status and on-going discussions on the handling of issues related to definitions of PEGs and PEPs as an input to the development of biosphere models for assessing radiological impacts on human health and the environment. The answers received to the questionnaire provided a clear overview of the progress that has been made since the original BIOMASS methodology was published, together with the lessons learned from the application of that methodology in the development of safety cases. This paper summarises the questionnaire responses in five subject areas: (1) environment of the PEGs and its evolution; (2) linking the choice of PEGs to these environments; (3) food habits and consumption rates; (4) populations of non-human biota (PEPs) and (5) national and international regulations and guidance. We illustrate how the results of the questionnaire have been used to enhance the original BIOMASS methodology (IAEA Enhanced BIOMASS Methodology Report in press).

CNC technology has become a requirement in the industrial world without complying with educational, pedagogical and private ratings. Manufacturers of this type of machine are trying to conform with the marketing requirements in terms of quality, price and quantity, so the CNC machine can meet the requirements and has acquired a leading position. The study and design of the three-axis CNC machine are based on the Fusion 360 software for the design and PROTEUS software for simulation to perfect our device.

We report on the nanopatterning of horizontal and vertical germanium-tin (Ge1−x Sn x or GeSn) nanowires by inductively coupled plasma reactive ion etching for gate-all-around field effect transistors. First, a chlorine based chemistry has been investigated and optimal conditions identified for GeSn 6% alloys. Then, plasma etching was optimized to etch high Sn content GeSn alloys (up to 15%) with a high anisotropy, smooth sidewalls and a high selectivity versus a hydrogen silsesquioxane hard mask. We have shown that, in order to obtain smooth surfaces after plasma etching, a HCl pre-treatment was mandatory to eliminate the native Sn and Ge oxides. This behavior was even more pronounced for high Sn contents. Finally, we succeeded in patterning 20 nm wide suspended beams from GeSn layers with Sn concentrations up to 15%.

Large-area electrochromic devices (ECDs) based on a cathodically-coloring, side chain-modified poly(3,4-ethylene dioxythiophene) (PEDOT) derivative and anodically-coloring Prussian blue (PB) are assembled by a customized sheet-to-sheet (S2S) lamination process. The ECDs with two complementary switching ""half-cells"", based on flexible PET-ITO substrates, offer enhanced optical properties in terms of visible light transmission change (4-53%), contrast ratio (CR = 93.4) and color neutrality (L* = 77.9, a* = −5.9, b* = −0.6) in the bleached state. The cycling stability is monitored for up to 10 000 switching cycles (97% charge retention). The reported optical, electrochemical, and in operando (in situ) spectroelectrochemical data are obtained from small laboratory-scale ECDs (active area: 5 × 5 cm2). These results, the homogeneity of the large-area devices and the scalability of the S2S lamination process are confirmed by measurements on the large ECDs with an active area of 45 × 65 cm2. This large-area electrochromic film technology with high optical contrast and enhanced cycling stability offers an excellent perspective for further development and scale-up towards pilot production and the commercialization of flexible ECDs upon their unique materials and processing characteristics.

Avoiding harmful passivation of the lithium metal surface during its implementation as an anode material is a challenge to its use in rechargeable lithium metal batteries. It is critical to control the chemical composition and the morphology of the native passivation layer and to avoid contamination by lubricants or other substances involved in the processing. Herein, abrasive blasting is used as a physical method to achieve clean and 3D-structured lithium metal electrodes. The careful choice of the abrasive agent and the blasting parameters results in well-controlled surface properties. The blasted lithium electrodes exhibit significantly lower overvoltages with values as low as 10 mV at 0.1 mA cm-2. Electrochemical impedance spectroscopy shows that blasted lithium has interface resistances that are up to five times smaller than those of untreated lithium. The effectiveness of blasting as a cleaning method is clear even in the case of thicker and highly resistive passivation layers occurring after exposure to ambient air.