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Moral panic, our predisposition to exaggerate threats against our livelihood and start blaming ourselves, is as old as human history. We always feared “others”, people with skin colors or ethnicity other than ours, people coming from other corners of the globe, and the infectious diseases the strangers might bring along. This paper deals with a new version of such moral panics which is arguably even more intense than the previous ones, but which relates to a new dimension of human experience, namely globalization. The health, economic and environmental challenges we are now faced with are posed globally. The moral panic today stems from this triple challenge. Our central thesis is that these three emergencies are interrelated, but there is no simple causal relationship between them. They can only be addressed in a global manner, while we still live in a world which is segmented into sovereign nation-states.

The energy yield of PV systems with horizontal single-axis tracking and bifacial panels was calculated using BIGEYE. BIGEYE is a versatile code developed at ECN part of TNO to calculate the yield of bifacial PV. Comparison to recent measured data with the BIFOROT set-up at the Zurich University of Applied Sciences showed very good agreement. Our BIGEYE results show that the bifacial energy gain and the tracking gain are mostly additive, making the combination of bifacial panels and tracking a very attractive option. For two different locations, Doha and Amsterdam, increases of energy yield in the order of 25% compared to monofacial, fixed tilt systems are possible at relatively modest ground cover values. 35th European Photovoltaic Solar Energy Conference and Exhibition; 1573-1577

Climate change is expected to alter the temporal distribution of precipitation events, leading to prolonged drought periods and an increased frequency of extreme precipitation events. Changes in precipitation pattern will directly affect soil moisture dynamics and further influence soil redox potential, biogeochemical processes and microbial community compositions. In this thesis, a series of experiments have been conducted to develop a thorough understanding of its impact. First, to investigate the interplay between soil moisture and redox potential dynamics, soil columns are manipulated to vary hydrologic and geochemical conditions and the spatio-temporal variations of their physical and biogeochemical conditions are recorded. The measurements of Eh, soil saturation and porewater chemical composition are used to develop a spatially explicit biogeochemical model that simulates reactive transport phenomena to describe quantitatively the spatio-temporal behavior of the redox potential along a vertical transect of a soil profile. The results of this experiment highlight the importance of joint spatially resolved hydrologic flow/transport and redox processes, the worth of contrasting experiments and computations for a sufficient understanding of the redox potential dynamics. Second, to investigate the impact of the redox regimes on the microbial community composition and probe the widespread hypothesis that the diversity of the redox fluctuating layer is greater than that of the zones with static redox conditions, a new 50-cm homogenized soil column is subjected to realistic intermittent artificial precipitation for 3 months. The hydrological and geochemical parameters are measured and microbial community compositions are analyzed as a function of time and depth. These results highlight the dominant role of vertical dissolved organic carbon gradients to the compositional trajectory of the microbiome and validate the previously-developed biogeochemical model with microbial and geochemical data. Finally, to investigate the impact of changing precipitation distribution on the soil microbial community composition at different depths and soil greenhouse gas emissions, three 50-cm homogenized soil columns are subjected to the sparse and intense precipitation for 3 months. Similar characterizations of soil hydrological, geochemical parameters and microbial compositions have been conducted and greenhouse gas fluxes are measured every 3-4 days. A change in the precipitation pattern increased the microbial diversity in both the oxic and anoxic zones of forest soil and the soil microbial community compositions varied between precipitation patterns in both oxic and anoxic zones. Results from this experiment highlight the importance of leaf litter decomposition in forest ecosystem as it being significantly correlated to the compositional trajectories of the forest soil microbiome and their associated biogeochemical processes. Additionally, our results reveal the dominant role of denitrification that contributes to N2O pulse emissions from soil under extended drought periods and extreme precipitation events.

To more accurately treat severe accidents in fast reactors, a program has been set up to investigate new computational models and approaches. The product of this effort is a computer code, the Advanced Fluid Dynamics Model (AFDM). This paper describes some of the basic features of the numerical algorithm used in AFDM. Aspects receiving particular emphasis are the fractional-step method of time integration, the semi-implicit pressure iteration, the virtual mass inertial terms, the use of three velocity fields, higher order differencing, convection of interfacial area with source and sink terms, multicomponent diffusion processes in heat and mass transfer, the SESAME equation of state, and vectorized programming. A calculated comparison with an isothermal tetralin/ammonia experiment is performed. We conclude that significant improvements are possible in reliably calculating the progression of severe accidents with further development.

This paper describes the modeling used in the Advanced Fluid Dynamics Model (AFDM), a computer code to investigate new approaches to simulating severe accidents in fast reactors. The AFDM code has 12 topologies describing what material contacts are possible depending on the presence or absence of a given material in a computational cell, the dominant liquid, and the continuous phase. Single-phase, bubbly, churn-turbulent, cellular, and dispersed flow are permitted for the pool situations modeled. Interfacial areas between the continuous and discontinuous phases are convected to allow some tracking of phenomenological histories. Interfacial areas also are modified by models of nucleation, dynamic forces, turbulence, flashing, coalescence, and mass transfer. Heat transfer generally is treated using engineering correlations. Liquid/vapor phase transitions are handled with a nonequililbrium heat-transfer-limited model, whereas melting and freezing processes are based on equilibrium considerations. The Los Alamos SESAME equation of state (EOS) has been inplemented using densities and temperatures as the independent variables. A summary description of the AFDM numerical algorithm is provided. The AFDM code currently is being debugged and checked out. Two sample three-field calculations also are presented. The first is a three-phase bubble column mixing experiment performed at Argonne National Laboratory; the second is a liquid-liquid mixing experiment performed at Kernforschungszentrum, Karlsruhe, that resulted in rapid vapor production. We conclude that only qualitative comparisons currently are possible for complex multiphase situations. Many further model developments can be pursued, but there are limits because of the lack of a comprehensive theory, the lack of detailed multicomponent experimental data, and the difficulties in keeping the resulting model complexities tractable.

The environmental sustainability is probably one of the most controversial topics of national policy agendas. The needs to combine economic growth and well-being, have forced governments to introduce tools for reducing CO2 emission and avoiding climate change. This paper aims to assess the effectiveness of these measures in the 1990-2014 period for a sample of 188 countries; and to analyze the determinants of CO2 in the 2000-2014 period for a sample of 175 countries. The results suggest that i) richest countries have a GDP elasticity of CO2 greater than that of poorest countries; and ii) GDP, energy consumption, urbanization, agricultural development, tourism and depletion of natural resources are directly correlated to CO2, while forest area, alternative energy, trade openness and FDI inflows are inversely related to CO2. Italian Review of Agricultural Economics, Vol 74 No 1 (2019)

Producing ions from large molecules is of distinguished importance in mass spectrometry. In our present study we survey different laser desorption methods in view of their virtues and drawbacks in volatilization and ion generation. Laser induced thermal desorption and matrix assisted laser desorption are assessed with special emphasis to the recent breakthrough in the field (m/z > 100,000 ions produced by matrix assisted laser desorption). Efforts to understand and describe laser desorption and ionization are also reported. We emphasize the role of restricted energy transfer pathways as a possible explanation to the volatilization of non-degraded large molecules.

The backscattered electron coefficient is known to be primarily dependent on the atomic number of the sample. If the atomic number increases, the backscattered electron coefficient increases, which results in a higher intensity in the backscattered electron image. The dependence of the primary electron energy is somewhat more complicated. Using photographic material (with composition AgBr-AgI), it is seen that the contrast in the backscattered electron image increases with the primary electron energy. Using three independent methods, based on image analysis techniques, it is shown that the difference between the backscattered electron coefficient of AgBr and AgI increases with the primary electron energy in the range from 40 to 100 keV.

This paper presents some recent results obtained from the COMMIX-1A code for the EBR-II reactor transient No. 10, Phase 2. Both the reactor vessel and the neutron shield assembly and assembly arrangement in the reactor core are shown. The computational grid system used in COMMIX-1A is presented. Reactor flow and power transients are shown. Velocity and temperature distributions at steady state and t (time) = 60 sec are included. Finally, a comparison between the calculated results from COMMIX-1A and experimental measurements are presented for outlet temperatures for driver subassembly of XX08, top-of-core temperature for driver subassembly of XX08, and low-pressure plenum mass flow respectively.