Agrivoltaic (AgV) co-locates crops and solar panels to mitigate land-use conflicts from rising production demands. This study advances AgV research by optimizing system efficiency through specific objective ratios for...
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Agrivoltaic (AgV) co-locates crops and solar panels to mitigate land-use conflicts from rising production demands. This study advances AgV research by optimizing system efficiency through specific objective ratios for cost and environmental impact. Four models are developed to assess optimal AgV site design and benefits: two mixed-integer nonlinear programs (MINLP) that independently target economic gains and operational emission reductions, and two fractional programming (FP) models that evaluate economic and environmental benefits per water consumed, with varying minimum cropland constraints. Applied to agricultural and solar sites at cornell university, Ithaca, New York, across seven crop types, optimal results from the MINLP models indicate that land should prioritize solar panels due to their superior economic and environmental benefits, with cabbage being the only exception due to its high crop value. In the FP models, prioritizing solar installation minimizes irrigation requirements, but economic benefits increase as more land is allocated to crops;a 90 % cropland allocation yields the highest revenues, ranging from 10.78 % to 186.77 % (US$5.86-34.88/m3) and achieving a land equivalent ratio of 4.40. The FP environmental model suggests limiting cropland to below 60 % for optimal emission reductions, reducing emissions to 54.01-112.18 metric tons of CO2eq/m3, which is lower than emissions from conventional separate crop and solar systems. The FP models balance economic and environmental benefits per irrigation unit, demonstrating AgV's water-use efficiency, and linking the complex relationship between inputs and outputs. Ultimately, site design choices should align with decision-makers' goals, whether prioritizing economic, environmental, or balanced system efficiencies.
In a circular accelerator, the nonlinear behavior near a horizontal resonance line usually involves the appearance of multiple stable fixed points (SFPs) in the horizontal phase space. The stable resonance islands sur...
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In a circular accelerator, the nonlinear behavior near a horizontal resonance line usually involves the appearance of multiple stable fixed points (SFPs) in the horizontal phase space. The stable resonance islands surrounding the SFPs in phase space are also referred to as transverse resonance island "buckets" (TRIBs) in the light source community. Specific conditions are required for TRIBs formation. At the cornell Electron Storage Ring, a new method is developed to improve the dynamic and momentum apertures in a 6-GeV lattice as well as to preserve the conditions for TRIBs formation. This method reduces the dimension of variables from 76 sextupoles to 8 group variables and then utilizes the robust conjugate direction search algorithm in optimization. Created with a few harmonic sextupoles or octupoles, several knobs that can either rotate the TRIBs in phase space or adjust the actions of SFPs are discussed and demonstrated by both tracking simulations and experimental results. In addition, a new scheme to drive all particles into one single island is described. Possible applications using TRIBs in a storage ring to characterize and calibrate accelerator hardware components are also discussed.
We develop a two-carrier Hall effect model-fitting algorithm to analyze temperature-dependent magnetotransport measurements of a high-density ( similar to 4x10(13)cm(-2)) polarization-induced two-dimensional hole gas ...
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We develop a two-carrier Hall effect model-fitting algorithm to analyze temperature-dependent magnetotransport measurements of a high-density ( similar to 4x10(13)cm(-2)) polarization-induced two-dimensional hole gas (2DHG) in a GaN/AlN heterostructure. Previous transport studies in GaN 2DHGs have reported a twofold reduction in 2DHG carrier density when cooled from room to cryogenic temperature. We demonstrate that this apparent drop in carrier density is an artifact of assuming one species of charge carrier when interpreting Hall effect measurements. Using an appropriate two-carrier model, we resolve light hole (LH) and heavy hole (HH) carrier densities congruent with self-consistent Poisson-k & sdot;p simulations and observe an LH mobility of similar to 1400 cm(2)/Vs and HH mobility of similar to 300 cm(2)/Vs at 2 K. This report constitutes the first experimental signature of LH band conductivity reported in GaN.
Nonconsumptive effects (NCEs) impact predator-prey interactions when the presence of a predator affects behavior, physiology, or population dynamics of the prey species without resulting in consumption. NCEs are criti...
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Nonconsumptive effects (NCEs) impact predator-prey interactions when the presence of a predator affects behavior, physiology, or population dynamics of the prey species without resulting in consumption. NCEs are critical to understanding ecological interactions broadly and in an applied manner, when addressing the efficacy of biological control within agroecosystems. In this study, we explore the impact of cues from the predator, Hippodamia convergens Gu & eacute;rin-M & eacute;neville (Coleoptera: Coccinellidae), on the probing and feeding behavior of Diaphorina citri Kuwayama (Hemiptera: Psyllidae), the Asian citrus psyllid (ACP), which transmits the causal bacteria of Huanglongbing (HLB) disease of citrus (Rutaceae). Due to wide-spread HLB incidence and insecticide resistance, it has become critical to better understand the activity of biological control agents within the HLB-ACP pathosystem. Utilizing electropenetrography (EPG), we investigated the feeding behavior of ACP exposed to the predator H. convergens or exposed to the chemical trails H. convergens produce while foraging. Overall, ACP detected H. convergens cues and responded by avoiding probing, although the extent of this response varied depending on the type of cue perceived. When H. convergens was present in the leaf but unable to reach the psyllid, ACP were slower to initiate probing and spent less time overall on probing and feeding from the xylem. In contrast, when exposed to H. convergens foraging cues without the beetle present, ACP initiated probing quicker than when the beetle was present and had a shorter total probing time compared to the control, with no other parameters being affected. Interestingly, the H. convergens chemical trail extracts, at two dosages, did not significantly influence ACP probing and feeding, except for a lower proportion of salivation and ingestion events into the phloem at the lower test dose. Our results suggest ACP exhibits avoidance behaviors in response to H. co
Co-Mn spinel oxide is a promising next-generation electrocatalyst that has previously shown oxygen reduction reaction activity that rivals that of Pt in alkaline fuel cells. Although the performance is encouraging, un...
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Co-Mn spinel oxide is a promising next-generation electrocatalyst that has previously shown oxygen reduction reaction activity that rivals that of Pt in alkaline fuel cells. Although the performance is encouraging, understanding the catalytic mechanisms in the oxygen reduction reaction is critical to advancing and enabling low-cost alkaline fuel cell technology. Here we use multimodal in situ synchrotron X-ray diffraction and resonant elastic X-ray scattering to investigate the interplay between the structure and oxidation state of a Co-Mn spinel oxide electrocatalyst. We show that the Co-Mn spinel oxide electrocatalyst exhibits a kinetically limited cubic-to-tetragonal phase transition, which is correlated to a reduction in both the Co and Mn valence states. Additionally, the electrocatalyst exhibits a reversible and rapid increase in tensile strain at low potentials during cyclic voltammetry, and joint density-functional theory is used to provide insight into how reactive adsorbates induce strain in spinel oxide nanoparticles.
High-entropy semiconducting nanocrystals involving the random incorporation of five or more metals within a single, disordered lattice are receiving significant research interest as catalytic materials. Among these, h...
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High-entropy semiconducting nanocrystals involving the random incorporation of five or more metals within a single, disordered lattice are receiving significant research interest as catalytic materials. Among these, high-entropy sulfide (HES) nanocrystals demonstrate potential as electrocatalysts but have been slower to gain research interest compared to other high-entropy systems due to the complications introduced by multistep, high-temperature synthesis techniques and the issues of material stability during performance. In this work, we report a simple, reproducible, and scalable HES synthesis to produce star-like nanocrystals. The HES nanocrystals show promise as electrocatalysts with high stability by maintaining a uniform overpotential within 1.5% of the initial value for over 2,200 cycles while rotating, with values as low as 313 mV at 10 mA/cm2 for the oxygen evolution reaction (OER) in alkaline media. Our work provides a low-temperature, colloidal method in the formation of highly complex, phase-pure thiospinel high-entropy sulfide nanocrystals.
The rapid expansion of artificial intelligence (AI)-enabled systems and cryptocurrency mining poses significant challenges to climate sustainability due to energy-intensive operations relying on fossil-powered grids. ...
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The rapid expansion of artificial intelligence (AI)-enabled systems and cryptocurrency mining poses significant challenges to climate sustainability due to energy-intensive operations relying on fossil-powered grids. This work investigates the strategic coupling of AI data centers and cryptocurrency mining through shared energy infrastructure including colocated renewable power installations, battery energy storage, green hydrogen infrastructure, and carbon offsetting measures to achieve cost-effective and climate-neutral operations. Employing a novel energy systems modeling framework, it explores synergistic AI-crypto operations with a detailed scenario design along with an optimization modeling framework to assess the decarbonization potential and economic implications, enabling a transformative shift in the digital landscape. The results indicate that synergizing the AI-crypto operations while achieving net-zero targets can avoid up to 0.7 Gt CO2-equiv through 2030. Moreover, reaching these targets with synergistic strategies globally requires up to 90.7 GW of solar power and 119.3 GW of wind power capacity. The findings advocate for robust policy measures that facilitate the strategic expansion of synergistic AI-crypto operations including carbon credit schemes tailored for the digital sector, incentives for energy efficiency improvements, and international collaborations to bridge economic disparities. Future research should focus on refining strategic interventions across different geopolitical contexts to enhance global applicability.
The ways in which people value wildlife, or "wildlife value orientations," shape attitudes and behaviors and can even predict support for environmental issues. As such, wildlife value orientations can be use...
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The ways in which people value wildlife, or "wildlife value orientations," shape attitudes and behaviors and can even predict support for environmental issues. As such, wildlife value orientations can be used strategically to inform communication strategies. We used a national, experimental framing survey (n = 1,998) to investigate how the two most predominant wildlife value orientations in the US - domination and mutualism - affect people's intentions to engage in conservation behaviors. Results showed that respondents on the mutualistic scale were more likely to express strong intentions to donate, engage in political activity, and adopt simple actions in support of conservation. In mutualistic-oriented respondents, pessimistically framed messages generally increased intentions to donate, but both optimistic and pessimistic-framed messages were likely to backfire and reduce intentions to adopt personal conservation actions. Our findings provide preliminary empirical evidence that wildlife value orientations could guide more effective communication approaches leading to behavior change.
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