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Environmental contamination of the Arctic has widely been used as a worldwide pollution marker. Various classes of organic pollutants such as pesticides, personal care products, PAHs, flame retardants, biomass burning markers, and many others emerging contaminants have been regularly detected in Arctic samples. Although numerous papers have been published reporting data from the Canadian, Danish, and Norwegian Arctic regions, the environmental situation in Russian Arctic remains mostly underreported. Snow analysis is known to be used for monitoring air pollution in the regions with cold climate in both short-term and long-term studies. This paper presents the results of a nontargeted study on the semivolatile organic compounds detected and identified in snow samples collected at the Russian Artic Archipelago Novaya Zemlya in June 2016. Gas chromatography coupled to a high-resolution time-of-flight mass spectrometer enabled the simultaneous detection and quantification of a variety of pollutants including those from the US Environmental Protection Agency (EPA) priority pollutants list, emerging contaminants (plasticizers, flame retardants-only detection), as well as the identification of novel Arctic organic pollutants, (e.g., fatty acid amides and polyoxyalkanes). The possible sources of these novel pollutants are also discussed. GC-HRMS enabled the detection and identification of emerging contaminants and novel organic pollutants in the Arctic, e.g., fatty amides and polyoxyalkanes. [ABSTRACT FROM AUTHOR]

Human space exploration requires massive budgets every fiscal year. Especially under severe financial constraint conditions, governments are forced to justify to society why spending so much tax revenue for human space exploration is worth the cost. The value of human space exploration might be estimated in many ways, but its social significance and cost-effectiveness are two key ways to gauge that worth. Since these measures should be applied country by country because sociopolitical conditions differ in each country and must be taken into consideration, the study on the social significance of human space exploration must take the coloration of a case-study. This paper, focusing on the case of Japan with surveying Japanese literary and national documents as well as taking its sociopolitical conditions into account, examines the social significance of human space exploration. First, we give an overview of the circumstances surrounding Japan's human space exploration program. Derived from the statements of such relevant parties as scholars, journalists, policy makers, and astronauts, this overview indicates that the main concerns about human space exploration in Japan are its social significance and cost-effectiveness (Section 1). Next, an overview of behavioral science—an essential field for human space exploration (referred to in this paper as space behavioral science) that provides support for astronauts—is presented from the perspective of stress research in isolated and confined environments (Section 2). We then give two examples of where such knowledge from space behavioral science research has been applied to terrestrial isolated and confined environments. One is JAXA’s support in 2009 for people who were vulnerable to infection by a new strain of flu and accordingly placed in an isolated and confined facility under the Infectious Disease Law and the Quarantine Law. The other is NASA's support in 2010 for Chilean mine workers who were trapped 700 m underground after a mining accident (Section 3). Based on these case studies, we illustrate the further social utility of such knowledge through a discussion of potential applications in other situations in Japan. Focusing on Japan for its geographical and social features in being an earthquake-prone archipelago and having the world's preeminent aging society, we show that refugees living in evacuation centers and people in an elderly-elderly homecare situation pose socially problematic situations specific to Japan. We then argue that space behavioral scientific knowledge can be applied to support people under these and other isolated and confined environments in various ways (Section 4). Finally, we demonstrate that such an application can be understood as an ethical contribution to Japanese society and that this contribution can be embedded in Japan's space policy (Section 5). We conclude that human space exploration can be a socially significant and cost-effective endeavor that is worthy of tax revenue expenditures because space behavioral science is highly likely to provide unique and useful knowledge to help address various social problems concerning terrestrial isolated and confined environments and support people in sufferings there. [ABSTRACT FROM AUTHOR]

• The concept of SPEV sharing is explored in the energy scheduling of clustering islands. • The space-temporal coupled characteristics of SPEV and battery packs are analyzed. • The energy scheduling and passenger scheduling constraints of SPEV are described. • An optimal energy scheduling model for clustering islands is established by considering the operational flexibility of SPEV. • Simulation results validate the effectiveness of the proposed model for the diversified operation demands of clustering islands. Pelagic clustering islands are rich sources of renewable energy. However, they are isolated by natural sea areas, making it difficult to realize the interconnectivity of energy generation and utilization among different types of clustering islands. This paper proposes the strategy of coordinated and optimal energy scheduling for pelagic clustering islands based on shared power exchanging vessels (SPEV). First, the energy interconnection model among different types of islands is analyzed based on the concept of SPEV sharing. Second, the space-temporal coupling of SPEV navigation is established by considering SPEV sharing transportation capacity and the charging-discharging state of mobile battery packs. On this basis, a clustering islands energy scheduling model is established to minimize the comprehensive operation costs of clustering islands, considering the battery pack charge–discharge constraints, SPEV navigation route constraints, and passenger traveling constraints. The established energy scheduling model fully explores the space-temporal energy transfer flexibility of SPEV considering meeting the travel demands of passengers. Finally, clustering islands in the South China Sea are considered in the case study, and the simulation results indicate that the proposed SPEV-based clustering islands energy scheduling strategy can effectively improve the renewable energy consumption rate and the operating economy of clustering islands. [ABSTRACT FROM AUTHOR]

[Display omitted] • MD simulation assesses effects of composition and operational conditions on asphaltene aggregation. • Effect of low concentration of OP on asphaltene aggregation is minor. • The most efficiency of OP is observed at 30 bar. • OP exhibits a greater performance at higher temperatures. • Sensitivity analysis assists to design an efficient inhibitor. The asphaltene stability in crude oil can be disturbed due to changes to thermodynamic conditions during production, raising flow assurance concerns. The addition of chemical inhibitors, such as surfactants, to a crude oil can improve the asphaltene stability. The impact of chemical inhibitors on the asphaltene aggregation intensity and aggregate characteristics, which is needed for design of an efficient inhibitor for a target crude oil, is poorly understood. In this paper, a molecular dynamics simulation tool is employed to simulate the molecular behaviour of the asphaltene and n -octylphenol (OP) at various concentrations of OP (0–15 wt%) and thermodynamic conditions (T = 300–360 K and P = 1–60 bar). To meet the objectives, the average aggregation number of different asphaltenes and asphaltene mixtures is measured besides the aggregate characteristics, including aggregate gyration radius, density, and shape. The results show that the archipelago asphaltenes (A1) do not self-aggregate severely, and the gyration radius distribution of the aggregates is similar after the OP addition. Nevertheless, the average aggregation number and the aggregate density analysis show that the aggregation intensity reduces slightly when the OP concentration is increased. Because the continental asphaltene (A2) can form hydrogen bonds, the addition of OP increases the aggregate dispersity significantly, which is identified with the highest peaks at 28 and 35 Å after the addition of 7 and 15 wt% OP, respectively. It is found that OP increases the variations in the aggregate shape and type for A2 aggregates. It is concluded that a high concentration of OP (above 7 wt%) is needed to avoid the asphaltene aggregation. The pressure increase does not change the aggregate shape both with or without the OP. However, adding OP increases the aggregate gyration radius and decreases the aggregate density at 30 bar. Increasing temperature results in a severe aggregation in the system without the inhibitor as the aggregate gyration radius increases, and aggregates become more compact and spherical. However, by adding OP, both the average aggregation number and aggregate gyration radius decrease (especially at 360 K). According to the sensitivity analysis results, integrating GPUs with CPUs can speed up the simulation approximately three times, compared to the system processing with only CPUs. Outcomes from this research work can help for a better understanding of the molecular behaviour of asphaltene and inhibitors at various thermodynamic situations, leading to the improvement of inhibitor design. This paper highlights the competence of molecular dynamics for exploring the optimal inhibitor concentration and the thermodynamic conditions in which the inhibitor has the highest impact on asphaltene aggregation. [ABSTRACT FROM AUTHOR]

• MD strategy is used to study impact of pressure on asphaltene self-aggregation. • Number and size of asphaltene aggregates considerably decrease with increasing pressure. • Face-to-face interactions are more likely than T-shaped and offset stacking for Gachsaran asphaltene. • In the upper asphaltene onset point zone, the tendency of molecules to move is decreased. • There is a good agreement between MD and experimental results. Asphaltene aggregation is a serious issue in the oil industry that negatively affects the production, transportation, and exploitation of oil, causing considerable costs. In the past few years, the experimental analysis of asphaltene aggregation has been a fascinating topic; however, a laboratory study that can assess the asphaltene aggregation behaviors at high pressures will be a costly and high-risk project. In this paper, molecular dynamics (MD) simulations are used to investigate the influence of pressure on the asphaltene aggregation phenomenon. The employed asphaltene in this research is Gachsaran asphaltene (obtained from an Iranian oilfield) with archipelago geometry. The aggregation number, radial distribution function (RDF), potential of mean force (PMF), cohesive energy, solubility parameter, mean square displacement (MSD), diffusion coefficient, relative concentration, potential energy, and radius of gyration are analyzed based on the data and results obtained from the output trajectory files. It is concluded that the number and the average size of asphaltene aggregates significantly decrease with increasing pressure because the pressure delays the growth of asphaltene aggregates by enhancing the asphaltene solubility parameter. The associated energies of asphaltene molecules at 35, 90, and 135 bar are calculated to be −15.7834, −15.7571, and −15.7249 kJ / mol, respectively. It is found that the tendency of asphaltene molecules to aggregate reduces upon an increase in pressure. Face-to-face interactions are more likely than T-shaped and offset stacking for this asphaltene sample because of the more aromatic nuclei in the asphaltene structure than the aliphatic chains, which increase the strength of the π-π interactions. It is also observed that by increasing pressure, the movement and vibration of asphaltene increase and then decrease by further increase in pressure. According to the asphaltene onset envelope diagram, the asphaltene molecules at 35 bar are located in the solid–liquid region. As the pressure increases to 90 bar, the asphaltene passes the upper asphaltene onset point zone. It can be concluded that when asphaltene is in the solid–liquid region, the mobility and displacement of molecules increase with increasing pressure. In the upper asphaltene onset point zone, the tendency of molecules to move is reduced. The MD results are consistent with the laboratory data. [ABSTRACT FROM AUTHOR]

As many other small islands and archipelagos, the Canary Islands depend to a high degree on energy imports. Despite its small surface, the archipelago has a high potential for renewable energy (RE) technologies. In this paper, we present a scenario pathway to a 100% RE supply in the Canary Islands by 2050. It relies on a back-casting approach linking the bottom-up accounting framework Mesap-PlaNet and the high resolution power system model REMix. Our analysis shows that locally available technology potentials are sufficient for a fully renewable supply of the islands’ power, heat, and land transport energy demands. To follow the pathway for achieving a carbon neutral supply, expansion of RE technology deployment needs to be accelerated in the short-term and efforts towards greater energy efficiency must be increased. According to our results, an extended linkage between energy sectors through electric vehicles as well as electric heating, and the usage of synthetic hydrogen can contribute notably to the integration of intermittent RE power generation. Furthermore, our results highlight the importance of power transmission in RE supply systems. Supply costs are found 15% lower in a scenario considering sea cable connections between all islands. [ABSTRACT FROM AUTHOR]

The ecosystem-based management of nearshore waters requires synthesis of spatial data on the distribution of ecological conditions and intensity of anthropogenic perturbations, and the overlay of their effects on the ecosystem health. An assessment framework for ecosystem health incorporating 4 components namely vigor, organization, resilience and maintenance was proposed in this paper, based on which an analytical approach was developed to quantify the integrated effects of island mass and anthropogenic pressures on the waters of nearshore archipelago. The southern waters of Miaodao Archipelago, which are located in the intersection of the Bohai Sea and the Yellow Sea, China, were taken as a typical example to acquire the spatial heterogeneity of the ecosystem health and its sensitivity to multiple anthropogenic pressures. Results indicated that there was a relatively significant performance of the spatial heterogeneity for the ecosystem health. It presented that the interisland waters were poorer health than the external waters, and the waters adjacent to the continent functioned less well than those in a relatively open area. This phenomenon was primarily determined by the performance of vigor as well as resilience of ecosystem. For the 4 components of ecosystem health, there were an obvious spatial heterogeneity of vigor as well as the resilience, a seasonal succession of organization, and a spatiotemporal uniformity of maintenance. Moreover, the ecosystem health was more sensitive to the stressors of inland activities and coastline exploitation especially in the waters of Miaodao Bay and Changdao Port. The analytical process and resulting maps provide flexible tools for regional efforts to implement ecosystem-based management in the waters of archipelago and further nearshore waters so as to promote their sustainable development. [ABSTRACT FROM AUTHOR]

The present paper addresses the conservation planning and management issues of terrestrial ecosystems with particular insight to small islands (with examples of application in the Macaronesian archipelagos of Cape Verde, Canaries, Madeira and Azores). It analyses specific conservation planning and management approaches and proposes concrete characterization and evaluation frameworks able to support decision and management processes ensuring an active and participative involvement of all concerned stakeholders. These methodological perspectives involve not only new paradigmatic approaches to the process of characterization and evaluation of environmental elements and processes as well as their use and disturbance through land use, but also regarding the individual and collective perspectives regarding benefice and supporting management behaviours. Some examples from islands of the Macaronesian archipelagos, in particular Pico in the archipelago of Azores and Santiago in the Cape Verde archipelago, are used to illustrate some possible management approaches, involving the consideration of the entire island as a conservation object and mobilizing their actors (individuals, groups, administrations or other organizations) as conscious, participative stakeholders. These examples involve possible land use and management changes and trade-off processes specific to each island that are listed and explained. [ABSTRACT FROM AUTHOR]

• The environmental impact on the energy supply, transmission and demand is analysed. • The energy transmission channel based on electric vessels and power flow balance relationship are modelled. • A scenario-based energy management system for pelagic clustering islands is first proposed. • The 2-stage method can solve the stochastic optimization model efficiently. The pelagic clustering islands (PCIs) can be developed into the resource rich islands (RRIs) and load center island (LCI) using the electric vessel (EV) to achieve interisland energy flow. However, energy balance between the supply and demand cannot be directly achieved, resulting in crucial need for effective day-ahead energy management for PCIs. To address this issue, this paper proposes a novel scenario-based energy management system (EMS) to optimize the operation of PCIs. To ensure the EMS performance, the comprehensive impact of environmental factors including wind, solar radiation and ocean currents on energy supply, transmission and demand is analysed in detail. The dynamic energy transmission channel and power flow balance relationship are modelled by evaluating the location and charging/discharging power of the EV. Considering the forecasting inaccuracies in environmental factors using refined stratified sampling (RSS) and scenario reduction methods, a stochastic optimization model is proposed to maximize the operational economy and reliability of PCIs, followed by a 2-stage solution consisting of preprocessing and group-search optimization with multiple producers (GSOMP). Simulation studies on Taiping Island, Hongma Island, Bolan Reef and Anda Reef in the South China Sea show that the proposed EMS is feasible and economical to describe the energy supply of PCIs. [ABSTRACT FROM AUTHOR]