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The atmosphere's surface layer (first 50-100 m above the ground) is extremely dynamic and is influenced by surface radiative properties, roughness, and atmospheric stability. Understanding the distribution of turbulence in the surface layer is critical to many applications, such as directed energy and free space optical communications. Several measurement campaigns in the past have relied on weather balloons or sonic detection and ranging (SODAR) to measure turbulence up to the atmospheric boundary layer. However, these campaigns had limited measurements near the surface. We have developed a time-lapse imaging technique to profile atmospheric turbulence from turbulence-induced differential motion or tilts between features on a distant target, sensed between pairs of cameras in a camera bank. This is a low-cost and portable approach to remotely sense turbulence from a single site without the deployment of sensors at the target location. It is thus an excellent approach to study the distribution of turbulence in low altitudes with sufficiently high resolution. In the present work, the potential of this technique was demonstrated. We tested the method over a path with constant turbulence. We explored the turbulence distribution with height in the first 20 m above the ground by imaging a 30 m water tower over a flat terrain on three clear days in summer. In addition, we analyzed time-lapse data from a second water tower over a sloped terrain. In most of the turbulence profiles extracted from these images, the drop in turbulence with altitude in the first 15 m or so above the ground showed a h m dependence, where the exponent m varied from -0.3 to -1.0, quite contrary to the widely used value of -4/3.
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Surface layer optical turbulence values in the form of the refractive index structure function C n2 are often calculated from surface layer temperature, moisture, and wind characteristics and compared to measurements from sonic anemometers, differential temperature sensors, and imaging systems. A key derived component needed in the surface layer turbulence calculations is the sensible heat value. Typically, the sensible heat is calculated using the bulk aerodynamic method that assumes a certain surface roughness and a friction velocity that approximates the turbulence drag on temperature and moisture mixing from the change in the average surface layer vertical wind velocity. These assumptions/approximations generally only apply in free convection conditions. To obtain the sensible heat, a more robust method, which applies when free convection conditions are not occurring, is via an energy balance method such as the Bowen ratio method. The use of the Bowen ratio--the ratio of sensible heat flux to latent heat flux--allows a more direct assessment of the optical turbulence-driving surface layer sensible heat flux than do more traditional assessments of surface layer sensible heat flux. This study compares surface layer C n2 values using sensible heat values from the bulk aerodynamic and energy balance methods to quantifications from sonic anemometers posted at different heights on a sensor tower. The research shows that the sensible heat obtained via the Bowen ratio method provides a simpler, more reliable, and more accurate way to calculate surface layer C n2 values than what is required to make such calculations from bulk aerodynamic method-obtained sensible heat.
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Ni- and Cu-rich concentrate from a new site in Suhanko, Finland, was investigated. Mineral phases identified included talc, chalcopyrite, kaolinite, and pyrrhotite with 3.2% Cu and 1.5% Ni, and the latter is associated with pyrrhotite. In addition, the concentrate contained the precious elements Pd (14.9 g/t), Ag (17.1 g/t), Pt (2.1 g/t), and Au (1.1 g/t). This concentrate was baked and leached using a Fe(III)-Cl--H2SO4 system. The results showed that the leaching efficiencies of Ni, Cu, and Si from raw concentrate were 60%, 40%, and 5%; however, those from baked concentrate were 96%, 60%, and below 0.1%, indicating that the baking process enhanced Ni and Cu extraction while simultaneously inhibiting the dissolution of Si, which was due to the baking process liberating the associated Ni and Cu by the oxidation of chalcopyrite and pyrrhotite and converting the acid-soluble silicate into an insoluble form. Sulfuric acid leaching solution with Fe(III) as oxidant and Cl- as lixiviant was shown to be effective at leaching Ni (97%), Cu (62%), and Ag (89%), while simultaneously enriching the PMs Pd, Pt, and Au in the residue.
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Achieving carbon neutrality requires deployment of large-scale renewable energy technologies like solar photovoltaic (PV) panels. Nevertheless, methods to ascertain the overall environmental impacts PVs and further improve their sustainability are under-investigated. In an effort to provide more understanding of this crucial topic, this research focuses on silicon flows-a key element for manufacturing crystalline silicon PVs. Using system dynamics modeling, we conduct a comprehensive environmental cost assessment of the silicon flows used in PVs based on a comparative analysis between the United States and China as the leading global PV manufacturers. Despite the advancement in wafer quality, material usage reductions and overall price decreases achieved in recent decades, our results project a substantial increase in energy and water consumption in China related to Metallurgical Grade Si (MG-Si), Solar Grade Si (SoG-Si) and cell manufacturing by 2030. An approximate 6.5 times increase of energy and water consumption is observed for c-Si cell manufacturing in China between 2010 and 2020. In 2030, increases of 70% in energy consumption and 69% in water use are estimated for Chinese MG-Si and SoG-Si production. The most significant environmental impact is observed in silicon cell and module manufacturing in both countries, particularly concerning GHG, SOx and NOx emissions. This study provides valuable insights into the environmental impacts of these two major solar panel manufacturing countries by examining the silicon life cycle, from production to end-of-life.
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The growing electric vehicle industry has increased the demand for raw materials used in lithium-ion batteries (LIBs), raising concerns about material availability. Froth flotation has gained attention as a LIB recycling method, allowing the recovery of low value materials while preserving the chemical integrity of electrode materials. Furthermore, as new battery chemistries such as lithium titanate (LTO) are introduced into the market, strategies to treat mixed battery streams are needed. In this work, laboratory-scale flotation separation experiments were conducted on two model black mass samples: i) a mixture containing a single cathode (i.e., NMC811) and two anode species (i.e., LTO and graphite), simulating a mixed feedstock prior to hydrometallurgical treatment; and ii) a graphite-TiO2 mixture to reflect the expected products after leaching. The results indicate that graphite can be recovered with > 98 % grade from NMC811-LTO-graphite mixtures. Additionally, it was found that flotation kinetics are dependent on the electrode particle species present in the suspension. In contrast, the flotation of graphite from TiO2 resulted in a low grade product (<96 %) attributed to the significant entrainment of ultrafine TiO2 particles. These results suggest that flotation of graphite should be preferably carried out before hydrometallurgical treatment of black mass.
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Grafito , Litio , Reciclaje/métodos , Suministros de Energía Eléctrica , IonesRESUMEN
Valorization of the lignocellulosic side and waste streams is key to making industrial processes more efficient from both an economic and ecological perspective. Currently, the production of sugars from beets results in pulps in large quantities. However, there is a lack of promising opportunities for upcycling these materials despite their promising properties. Here, we investigate beet pulps from two different stages of the sugar manufacturing process as raw materials for supercapacitor electrodes. We demonstrate that these materials can be efficiently converted to activated, highly porous carbons. The carbons exhibit pore dimensions approaching the size of the desolvated K+ and SO42- ions with surface areas up to 2600 m2 g-1. These carbons were subsequently manufactured into electrodes, assembled in supercapacitors, and tested with environmentally friendly aqueous electrolytes (6 M KOH and 1 M H2SO4). Further analysis demonstrated the presence of capacitance-enhancing functionalities, and up to 193 and 177 F g-1 in H2SO4 and KOH, respectively, were achieved, which outperformed supercapacitors prepared from commercial YP80 F. Overall, our study suggests that side streams from sugar manufacturing offer a hidden potential for use in high-performance energy storage devices.
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Background: Idiopathic granulomatous lobular mastitis (IGLM) is a rare, chronic inflammatory breast disease without a known etiology. Even though the current literature proposes several treatment strategies, there is no universal consensus for long-term management. Case Presentation: A 43-year-old White woman (gravida 5, para 4) presented with a 2-week history of right lower outer quadrant breast tenderness, heaviness, warmth, and redness. Mammography and ultrasound were concerning for inflammatory breast cancer. Biopsies returned as granulomatous mastitis without malignancy. After 8 months of unsuccessful therapy with prednisone and methotrexate, surgeons excised the breast tissue. Cultures and special stains were negative for other organisms. At the 7-month follow-up, no evidence of recurrence was seen. Conclusions: As there remains no consensus behind the etiology or management of IGLM, our case demonstrates a reasonable and successful stepwise treatment beginning with medical therapy before proceeding to surgical cure. Because of possible malignancy risk with chronic IGLM, patients should not delay surgical excision if their condition remains refractory to medical therapy alone.