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We present ionization cross sections of hydrogen molecules by electron and positron impact for impact energies between 20 and 1000 eV. A three-body Classical Trajectory Monte Carlo approximation is applied to mimic the collision system. In this approach, the H2 molecule is modeled by a hydrogen-type atom with one active electron bound to a central core of effective charge with an effective binding energy. Although this model is crude for describing a hydrogen molecule, we found that the total cross sections for positron impact agree reasonably well with the experimental data. For the electron impact, our calculated cross sections are in good agreement with the experimental data in impact energies between 80 eV and 400 eV but are smaller at higher impact energies and larger at lower impact energies. Our calculated cross sections are compared with the scaled cross sections obtained experimentally for an atomic hydrogen target. We also present single differential cross sections as a function of the energy and angle of the ejected electron and scattered projectiles for a 250 eV impact. These are shown to agree well with available data. Impact parameter distributions are also compared for several impact energies.

Joining of pure copper C1100 and aluminum alloy A6061-T6 plates of 5 mm thickness was investigated. The method was developed by one of the authors, in which the newly created surfaces of a pair of plates obtained by high-speed shear were immediately in contact with a sliding motion with a small overlap length. The total processing time was just about a few milliseconds. To create the new surface, high-speed shaving was also tested. The joining was not possible for the full thickness of the plates. A sharp notch was observed at the joint boundary due to a large shear droop in the copper. Shaving decreased the shear droop, and the joint length through the plate thickness became longer. The joining performance was evaluated by a uniaxial tensile test. The joint efficiency reached 100% using the specimen cut out from the really joined boundary. The affected zone of joining was confirmed by the hardness distribution near the boundary. It was about 30% of the thickness of the plate, which was much smaller than that in welding by heat, and no softened zone was found in both materials.

Troctolite sample 76535, collected in Serenitatis basin during Apollo 17, formed at least 50 km deep, experienced maximum shock pressures of 6 GPa, and has a 40Ar/39Ar excavation age of 4.25 Ga. Previous work attributed 76535 to the South Pole‐Aitken (SPA) basin, presumably dating the SPA‐impact and constraining lunar bombardment history. Here we use the iSALE‐2D shock‐physics code and gravity inversion modeling to determine if instead the Serenitatis impact event excavated 76535. We find nearly 140,000 km3 of material (∼2% of near‐surface ejecta) matching the depth and pressure constraints of 76535 is displaced to the surface during crater collapse of a Serenitatis‐like impact event. We conclude that the Serenitatis impact event possibly excavated 76535, redefining its age to 4.25 Ga, 300 My older than the consensus age based on Apollo 17 samples. This finding would provide an important anchor point where lunar chronology where bombardment flux is especially uncertain.

The surface geology of Jupiter’s Trojan asteroids is one of the scientific investigations of the NASA Lucy mission. A dedicated Geology Working Group will implement these studies using primarily panchromatic and color imaging data and complement the interpretation of these data with theoretical models, such as collisional evolution models. The Lucy Science Team will also rely on experience and lessons learned from prior space missions, such as NASA’s NEAR , Dawn, OSIRIS-REx , and New Horizons . A chief goal of the Geology Working Group is to map craters and characterize their morphology across Lucy target’s surfaces over a range of spatial resolutions. These data will be used to constrain the relative and absolute ages of terrains and their impactor size-frequency distributions. More broadly, impact-related processes such as excavation and mass wasting will inform other investigations, including geological unit mapping, stratigraphy and topography, surface composition, and internal structure. Lucy ’s cratering data and morphology will also be used to perform comparative analyses with similar data from other small bodies across the Solar System, from Main Belt asteroids to Kuiper Belt objects. The present article provides an overview of the planned activities and methodologies of the Geology Working Group.

PURPOSE: This report proposes a life-cycle analysis (LCA)-oriented methodology for systematic inventory analysis of the use phase of manufacturing unit processes providing unit process datasets to be used in life-cycle inventory (LCI) databases and libraries. The methodology has been developed in the framework of the CO2PE! collaborative research programme (CO2PE! 2011a) and comprises two approaches with different levels of detail, respectively referred to as the screening approach and the in-depth approach. METHODS: The screening approach relies on representative, publicly available data and engineering calculations for energy use, material loss, and identification of variables for improvement, while the in-depth approach is subdivided into four modules, including a time study, a power consumption study, a consumables study and an emissions study, in which all relevant process in- and outputs are measured and analysed in detail. The screening approach provides the first insight in the unit process and results in a set of approximate LCI data, which also serve to guide the more detailed and complete in-depth approach leading to more accurate LCI data as well as the identification of potential for energy and resource efficiency improvements of the manufacturing unit process. To ensure optimal reproducibility and applicability, documentation guidelines for data and metadata are included in both approaches. Guidance on definition of functional unit and reference flow as well as on determination of system boundaries specifies the generic goal and scope definition requirements according to ISO 14040 (2006) and ISO 14044 (2006). RESULTS: The proposed methodology aims at ensuring solid foundations for the provision of high-quality LCI data for the use phase of manufacturing unit processes. Envisaged usage encompasses the provision of high-quality data for LCA studies of products using these unit process datasets for the manufacturing processes, as well as the in-depth analysis of individual manufacturing unit processes. CONCLUSIONS: In addition, the accruing availability of data for a range of similar machines (same process, different suppliers and machine capacities) will allow the establishment of parametric emission and resource use estimation models for a more streamlined LCA of products including reliable manufacturing process data. Both approaches have already provided useful results in some initial case studies (Kellens et al. 2009; Duflou et al. (Int J Sustain Manufacturing 2:80–98, 2010); Santos et al. (J Clean Prod 19:356–364, 2011); UPLCI 2011; Kellens et al. 2011a) and the use will be illustrated by two case studies in Part 2 of this paper (Kellens et al. 2011b).

Surface unloading due to impact cratering results in lava filling the crater floor. Elevation differences in the crater floor, a common geological phenomenon on the Moon, represent direct evidence of cratering processes. However, few studies have been conducted on mare-filled craters on the Moon. Al-Biruni (81 km) is a farside impact crater with an inclined topographic profile on its floor. We quantitatively measure the morphology of Al-Biruni and model the basaltic lava emplacement to depict the cratering process. Differential subsidence due to melt cooling, wall collapse, impact conditions and structural failure were assessed as potential factors influencing the formation of the elevation differences on the floor. The results suggest that pre-impact topography is a plausible cause of the differences in floor elevation within Al-Biruni. Other factors may also play a role in this process, affecting lava flow by altering the topography of the crater floor after the impact. Thus, regardless of whether the lava inside the crater is impact-generated or comes from outside the crater, altering topography at different stages of the cratering process is an essential factor in creating the sloped terrain on the crater floor.

To investigate the impact of a road safety programme on adolescents' willingness to engage in risky behaviour as probationary drivers, adjusted for covariates of interest. The streetsmart is a road safety programme delivered to around 25 000 adolescent students annually in New South Wales. Using a smartphone-based app, student and teacher participation incentives, students were surveyed before and after programme attendance. Mixed-methods linear regression analysed pre/post-modified Behaviour of Young Novice Driver (BYNDS_M) scores. 2360 and 1260 students completed pre-event and post-event surveys, respectively. Post-event BYNDS_M scores were around three points lower than pre-event scores (-2.99, 95% CI -3.418 to -2.466), indicating reduced intention to engage in risky driving behaviours. Covariates associated with higher stated intentions of risky driving were exposure to risky driving as a passenger (1.21, 95% CI 0.622 to 2.011) and identifying as non-binary gender (2.48, 95% CI 1.879 to 4.085), adjusting for other predictors. Trauma-informed, reality-based injury prevention programmes can be effective in changing short-term stated intentions to engage in risky driving, among a pre-independent driving student population. The adolescent novice driver age group is historically challenging to engage, and injury prevention action must be multipronged to address the many factors influencing their behaviour.

We present the results of geological mapping of Mercury's Derain (H10) quadrangle (0°-72°E and 22.5°N-22.5°S) using data from the MESSENGER spacecraft. The map is presented on a scale of 1:3,000,000, for which linework was drawn at 1:300,000. We distinguish three major morphological plains units: Smooth, Intermediate, and Intercrater Plains. We produced two versions of the map, with craters classified according to a 3- and 5-class degradation system. This allows compatibility with other MESSENGER-era maps and Mariner 10-era maps. This map will help provide science context for the ESA-JAXA BepiColombo mission to Mercury.

Past and present anthropogenic mercury (Hg) release to ecosystems causes neurotoxicity and cardiovascular disease in humans with an estimated economic cost of $117 billion USD annually. Humans are primarily exposed to Hg via the consumption of contaminated freshwater and marine fish. The UNEP Minamata Convention on Hg aims to curb Hg release to the environment and is accompanied by global Hg monitoring efforts to track its success. The biogeochemical Hg cycle is a complex cascade of release, dispersal, transformation and bio-uptake processes that link Hg sources to Hg exposure. Global change interacts with the Hg cycle by impacting the physical, biogeochemical and ecological factors that control these processes. In this review we examine how global change such as biome shifts, deforestation, permafrost thaw or ocean stratification will alter Hg cycling and exposure. Based on past declines in Hg release and environmental levels, we expect that future policy impacts should be distinguishable from global change effects at the regional and global scales.

BackgroundExplosive remnants of war claim more than three lives every day in Afghanistan. This study evaluates the impact of BBC Media Action Afghanistan’s Explosive Ordnance Risk Education project in raising public awareness and promoting safe behaviours regarding explosive ordnances in Afghanistan. The project deployed a multimedia approach to reach a mass audience, including a radio discussion show, public service announcements on TV and radio, social media content and playing content on intercity buses.MethodsA panel study with 400 participants from high-risk provinces assessed knowledge, discussion and behavioural intentions related to explosives before and after a mass media intervention. In the broadcast period, the research unobtrusively monitored the dosage of exposure to the media content.ResultsFindings from the panel study indicated a significant increase in discussions about explosive risks and safer behavioural interventions (e.g. avoiding and reporting explosive ordnances) post intervention.ConclusionThe results constitute one of the first pieces of systematically collected evidence on media and communication’s potential in explosive risk education by facilitating interpersonal discussion and in turn change of behavioural intentions in areas contaminated by explosive ordnances and remnants of war.