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Internal Solitary Waves (ISWs) that form on internal density interfaces in the ocean are responsible for the horizontal transport and vertical mixing of heat, nutrients, and other water properties. The waves also induce fluid motion that can induce stresses and motion on floating structures, such as sea ice. This study investigates ISW‐sea ice interactions. Using laboratory experiments, ISWs generated via the lock gate technique are observed interacting with weighted floats of varying sizes. The motion of these floats can be modeled effectively, simply as the average velocity of the fluid under the float, and it is found that when floats are small relative to the wavelength, they behave in the same manner as a fluid particle, but as floats become bigger relative to the wavelength, the maximum velocity decreases, and interaction time increases. This phenomenon is explained simply by the wave‐induced flow as opposed to energy transfer arguments. By using this model with a large sample of theoretical waves, the float motion is parameterized based on the float length and wave parameters. Whilst small floats do not disrupt the flow patterns, the wave‐induced flow under larger floats forms a pair of counter‐rotating vortices at each end of the float. The formation and evolution of these flow features arise as a result of boundary layer separation with the horizontal wave‐induced flow relative to the float velocity. This reveals complex dynamics due to the non‐stationary behavior of both the float and flow. Plain Language Summary: Underwater waves are found in oceans across the world, including in areas with sea ice. They help mix heat, salt and other constituents in the ocean between deep and shallow waters. The Arctic is changing quickly, with summer sea ice extent declining 12.6% per decade, so we are now finding internal waves in newly ice‐free areas. Experiments are used to understand how these waves interact with sea ice. It is found that bigger floats move more slowly and create more flow disturbance, albeit not enough to cause mixing. The way this flow behaves is complicated by the movement of both the model ice, and the wave. Further experimental work is needed to understand the impact of changing the thickness, concentration and shape of the ice on the behavior of these waves. Key Points: Internal Solitary Waves (ISWs) can interact with sea ice in the Arctic Ocean. This process is modeled using laboratory experimentsThe wave‐induced motion of ice is slower when the ice length is large in comparison to the wave, a result explained by the wave form aloneVortices form at the ice edge. They are boundary layer features that depend on the motion of both the ice and ISW [ABSTRACT FROM AUTHOR]

Small‐scale wind turbines have market opportunities in distributed energy generation applications but face future challenges in remaining cost competitive compared with solar photovoltaic systems. High unit costs can be attributed to design conservatism when calculating fatigue loads of key structural components such as the blades. In this study, we use the aeroelastic software FAST to highlight limitations of the International Electrotechnical Commission 61400‐2:2013 small wind turbine design standard for calculating fatigue life using the simplified load model. We present a modified method for calculating the fatigue spectra of small wind turbine blades. An advantage of this method is that it does not require complex aeroelastic simulations or field measurements. This modified method is intended to be implemented early in the blade design stage, such as during rotor optimization simulations, allowing for multiple rotor configurations to be rapidly compared. [ABSTRACT FROM AUTHOR]

In this study, an energy and highly time efficient, cost effective, and scalable forward osmosis (FO) composite polyvinylidene fluoride (PVDF) membrane is developed to concentrate lithium chloride recovered from naturally occurring geothermal brine resources. Dense thin robust defect-free Kynar-PVDF membranes are fabricated on porous PVDF hollow fiber supports. Various membrane fabrication parameters such as membrane thickness, coating solution concentration, cross-linker concentration, and curing temperature are studied to develop a defect-free dense membrane. Advanced characterization tools such as FIB-SEM, Raman, FTIR spectroscopy, and XRD are used to study the surface and cross-sectional morphology, chemistry of crosslinking, crystallinity and chemical structure of the dense PVDF membrane. FO is utilized to concentrate LiCl in the solution from 36 to 175 g L-1 with an average water transfer rate of 0.450 L m-2 h-1 (LMH) at 85 °C. Furthermore, the membrane showed stable performance for more than 550 h while maintaining the purity of the concentrated lithium chloride solution of >99.99 wt%. The results suggest that the FO-based technology is an innovative, time and energy efficient approach compared to the conventional technologies for concentration of battery grade LiCl for application in lithium ion batteries and other clean energy technologies. [ABSTRACT FROM AUTHOR]

Layered aluminum double hydroxide chloride sorbents, LiCl∙Al2(OH)6.nH2O, Li‐LDH, have shown promising application in selective Li extraction from geothermal brines. Maintaining LiCl uptake capacity and retaining a long cycle life are critical to widespread application of sorbent materials. To elucidate the energetics of Li capture, enthalpies of LDH with different Li content have been measured by acid solution calorimetry. The formation enthalpies generally become less exothermic as the Li content increases, which indicates that Li intercalation destabilizes the structure, and the enthalpies seem to approach a limit after the Li content x = 2Li/Al exceeds 1. To improve stability, metal doping of the aluminum LDH structure with iron was performed. Introduction of a metal with greater electron density but a similar ionic radius was postulated to improve the stability of the LDH crystal structure. The calorimetric results from Fe‐doped LDH samples corroborate this as they are more exothermic than LDH‐lacking Fe. This suggests that Fe doping is an effective way to stabilize the LDH phase. Layer double hydroxide (LDH) structure (left) and formation enthalpies vs various compositions (right). [ABSTRACT FROM AUTHOR]

Understandings of contemporary forest cover loss are critical for policy but have come at the expense of long-term, multidirectional analyses of land cover change. This is a critical gap given (i) profound reconfigurations in land use and land control over the past several decades and (ii) evidence of widespread 'woodland resurgence' throughout the tropics. In this study, we argue that recent advancements within the field of land change science provide new opportunities to address this gap. In turn, we suggest that multidecadal and multidirectional analyses of land cover change can facilitate richer social analyses of land cover change and more relevant conservation policies and practice. Our argument is grounded in a case study from Southeast Sulawesi, Indonesia. Using a novel analytical platform, Google Earth Engine, and open access to high-quality Landsat data, we map land cover change in Southeast Sulawesi, Indonesia, from 1972 to 2014. We find that tree cover loss constitutes the single largest net change over the period 1972-2014 but that gross rates of tree cover gain were three times higher than gross loss rates from 1972 to 1995 and equivalent to loss rates from 1995 to 2014. We suggest the smallholder tree crop economy likely produced both forest loss and Imperata grassland restoration in this region. This case points to the need to expand rather than collapse the baselines used to study carbon and biodiversity change in tropical regions. It also demonstrates the possible utility of applying such methods to other regions. [ABSTRACT FROM AUTHOR]

The population in developed countries is ageing and the number of people experiencing joint-related conditions, such as osteoarthritis, is expected to increase. Joint replacements are currently the most effective treatment for severe joint conditions and although many of these procedures are successful, infection developing after the procedure is still an issue, requiring complex and expensive revisions. Whilst incorporating a powdered antibiotic within the bone cement can reduce infection rates, the powder frequently agglomerates, resulting in poor antibiotic release characteristics and compromised mechanical performance of the cement. To overcome these issues, a novel delivery system consisting of antibiotic-loaded nano-sized liposomes was developed for inclusion into polymethyl methacrylate (PMMA) bone cement. This system was tested in a commercial cement (Palacos R) and consistently delivered a higher percentage (22%) of the incorporated antibiotic when compared to the powdered antibiotic cement (9%), meaning less antibiotic needs to be incorporated than with conventional cement. The novel system resulted in a controlled and gradual release of antibiotic over a longer, 30-day period and enhanced the toughness, bending strength and Vickers hardness of the cement, without altering its polymerization or molecular structure. This new material has the potential to significantly reduce infections in cemented joint replacements leading to enhanced patient quality of life and reduced healthcare costs. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1510-1524, 2016. [ABSTRACT FROM AUTHOR]

The recent increase in corn ethanol production has drawn attention to the environmental sustainability of biofuel production. Environmental assessments of second-generation biofuel crops ( SGBC) have focused primarily on greenhouse gas emissions and water quality. However, expanding the production of cellulosic biomass resources, especially those that require dedicated agricultural land, is also likely to have impacts on biodiversity. We developed an optimization framework for projecting the spatial pattern of SGBC expansion in the United States and intersected these predictions with occurrence data for at-risk species. In particular, we focused on two candidate perennial grass feedstocks, Panicum virgatum (switchgrass), and Miscanthus × giganteus (Miscanthus). Tradeoffs between biodiversity and economic profitability are assessed using county level data sets of SGBC yield, agricultural land availability, land rents, and at-risk species occurrences. Results show that future SGBC expansion is likely to occur outside of the Corn Belt, where conventional biofuel feedstocks are currently grown. The set of at-risk species that could potentially be impacted is therefore likely to be different from the at-risk species prevalent in the agroecological landscapes of the Upper Midwest that are dominated by corn and soy production. The total number and type of potentially impacted taxa is influenced by several factors, including the total demand for cellulosic biomass, the type of agricultural land used for production, and the method for defining at-risk species. SGBC production is also concentrated in fewer counties when a national species conservation constraint is combined with a biofuel production mandate. This analysis provides a foundation for future research on species conservation in bioenergy production landscapes and highlights the importance of incorporating biodiversity into broader environmental assessments of biofuel sustainability. [ABSTRACT FROM AUTHOR]