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Results for “MIGRATION”
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Inactivation of the phenylpyruvate tautomerase activity of macrophage migration inhibitory factor by 2-oxo-4-phenyl-3-butynoate
Abstract not provided
Analysis of moisture migration in concrete at high temperature through in-situ neutron tomography
Spalling, which is a phenomenon encountered when high-performance concrete is exposed to high temperature, can lead to large economical damage and can be a major safety hazard. Moisture distribution in concrete during exposure to fire is of paramount importance for understanding the complex mechanism of this phenomenon. To capture in its fullness this mechanism, it is crucial to account for the heterogeneous nature of concrete. In this paper, the first 3D analysis of moisture distribution in concrete at high temperature through in-situ neutron tomography is presented. The world-leading flux at the Institute Laue Langevin in Grenoble, France allowed capturing one 3D scan per minute, which is sufficient to follow the fast dehydration process. The paper describes the experimental setup with the heating system and discusses in detail the framework of the neutron tomography test. Quantitative analysis showing the effect of the aggregate size on the moisture distribution is presented.
Biomass and salt-dependent effects of Bacillus spores on radionuclide migration from the Waste Isolation Pilot Plant
Spores of a Bacillus sp., isolated from radioactive waste, were tested for their ability to influence the fate and transport of neodymium (Nd3+) under high salt conditions expected at the Waste Isolation Pilot Plant (WIPP) nuclear waste repository. Spores were suspended in neodymium-spiked saline solutions up to 4 M NaCl, and concentrations of Nd and the complexing agent dipicolinic acid (DPA), a component of spores, were monitored along with optical densities and spore numbers. Overall, results support neodymium bioassociation that is dependent upon biomass, with more apparent adsorption occurring at higher spore concentrations. However, probable spore lysis in 2 and 4 M NaCl solutions and possible germination at 0.15 M NaCl appear to drive the release of DPA and subsequent return of Nd to solution. The implications of this work for the WIPP will depend on actual biomass levels and the ionic strength of the repository brines.
Identification of unknown compounds from polyester cans coatings that may potentially migrate into food or food simulants
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Interpreting oxygen vacancy migration mechanisms in oxides using the layered structure motif
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Dislocation migration across coherent phase interfaces in SiGe superlattices
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Role of atomic migration in nanocrystalline stability: Grain size and thin film stress states
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Modeling autumn migration of a rare soaring raptor identifies new movement corridors in central Appalachia
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Improved Particle Tracking Proxy for Assessing Plume Migration during Geologic Sequestration
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Migrating Populus with climate change: Phenology, coppice management, cold spell susceptibility, leaf dynamics, and biomass production
Understanding the phenology and productivity of Populus species is crucial for effective management and conservation strategies amid climate change. We investigated leaf budbreak timing, susceptibility to cold damage, leaf dynamics, and biomass production of 168 Populus genotypes with diverse provenances in the southeastern United States. Our study revealed significant variation in budbreak timing across different taxa and years, with genotypes inheriting traits adapted to their parents’ local climates. Temperature emerged as a key factor triggering budbreak, while leaf development depended on other environmental cues such as photoperiod. Notably, budbreak occurred approximately 20 days earlier in 2023 compared to 2022 due to higher accumulated degree days (ADDs). Short-rotation-coppice (SRC) management delayed budbreak by five to ten days. Cold damage was significant in 2023, particularly for genotypes from northern provenances and those with P. maximowiczii parentage. Severe damage was also observed in eastern cottonwood ( Populus deltoides × Populus deltoides (D × D)) genotypes, despite most having southeastern US parentages. Leaf dynamics, including leaf duration and leaf area index (LAI), varied across taxa and sites, with earlier budbreak correlating with extended growing seasons and increased LAI. Biomass production was intricately linked to phenological events, with earlier budbreak leading to increased biomass production and greater susceptibility to cold damage. Our findings highlight the importance of genetics, environment, and coppicing management in understanding and managing Populus phenology and biomass production. These insights provide valuable guidance for developing effective breeding, conservation, and management strategies for Populus species in the context of climate change.
Determining the migration of nadic acid, terephthalic acid, isophthalic acid and two oligomers from polyester food cans into food in the U.S. market
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