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Showing 1 to 20 of 51 for “"macropores"”.
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Abundance, Distribution, and Geometry of Naturally Occurring Macropores in Stream Banks
… higher permeability than surrounding media. Macropores and soil pipes are a type of preferential flow path where conduit-like voids in the subsurface are typically greater than three millimeters in diameter. They are known to occur in agricultural and forest soils, often as a result of …
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Modeling transport of agricultural chemicals in a dual porosity system resulting from macropores
A conceptual model, based upon the bicontinuum double porosity approach, has been developed to simulate water flow and reactive chemical transport in both the soil matrix and the macropore region. Flow of water in both regions is governed by Richards' equation and chemical transport is based upon …
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Quantifying soil compaction effects on soil macropores and corn root morphology through image analysis
Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2025-10-19 without embargo terms
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Preferential and Non-Darcy Flows in the Hyporheic Zone: Surface Water-Groundwater Hydraulics and Effects on Stream Functions
… flow-rate or residence time. The importance of macropores to hyporheic transport through meander bends was explored. Transport velocities, hydraulic head gradients, and solute transport rates through the meander bend were increased by macropores. Results indicate that macropores can dictate …
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Measurement and Simulation of Preferential Flow in Frozen Soils
… of cold regions. Preferential flow in macropores may enhance infiltration into frozen soil, but flow dynamics are complicated by coupled water and heat transfer processes. Field studies were conducted in the Canadian Prairies to evaluate the dominant mechanisms controlling preferential …
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Development and optimisation of supercritical fluid deposition of semiconductor films
… mixtures. Ge was deposited into macropores etched into crystalline silicon substrates. A variety of reactors were designed in order to achieve the successful deposition of the materials. The surface morphology and crystallinity of the films were characterised by scanning electron …
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Preferential movement of solutes through soils
… in heterogeneous soils with naturally occurring macropores were developed and evaluated. Field experiments, aimed at monitoring the occurrence of preferential flow and solute transport, were conducted in a conventionally-tilled and a no-till soybean field in the Coastal Plain of Virginia. A …
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Macro- and micro-structural features direct bone regeneration in patterned biphasic calcium phosphate scaffolds
… calcium phosphate (BCP) scaffolds with both macropores and micropores (MP) show enhanced bone healing compared to those with macropores and no micropores (NMP), but the role of micropores is unclear. In this work, we assess the influence of scaffold macro- (> 300 μm) and microporosity (< 50 …
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Design and fabrication of non-noble-metal electrocatalysts for oxygen reduction reactions.
… from large mesopores (ca. 12 nm) to large macropores (ca. 400 nm) and studied the structural impact of these hybrid materials on their ORR performance. In this study, we have for the first time revealed that macropores would be more favorable for ORR in such materials rather than the …
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Layer-by-layer carbon nanotube electrodes for flexible chemical sensor and energy storage applications
… micron in thickness, contained 3D interconnected macropores and mesoporous network of LbL-MWNT films. HP-MWNT electrodes can deliver a high gravimetric energy of ~100 Wh kg-1 at a gravimetric power of -25 kW kg' in lithium nonaqueous cells. Compared to similar MWNT electrodes without macropores, …
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Microbial transport in volcanic tuff Rainier Mesa, Nevada test site
… appeared to be transported through connected macropores or fractures in tuff cores. Laboratory and field results demonstrated that bacteria were transported with water predominantly along preferred water flow paths in rock.
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Engineering carbon nanostructures : development of novel aerogel-nanotube composites and optimization techniques for nanotube growth
… by templating a network of interconnected macropores into the monoliths. Surface-based nanoparticles composed of rhenium, gold, and varying combinations of gold and rhenium were investigated for their ability to catalyze carbon nanotube growth.
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Evaluation of sewer leakage into the stormwater drainage system in Singapore
… pathways such as concrete cracks or soil macropores. Sewage does not appear to be traveling through the soil porous medium. Further studies are needed to determine if groundwater is a medium of transport of exfiltrated sewage.
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A novel non-invasive optical method for quantitative visualization of pH and oxygen dynamics in soils
… structures such as aggregates, roots, layers or macropores enhance the patchiness of these distributions. At the same time it is difficult to access the spatial distribution and temporal dynamics of these parameter. Noninvasive imaging techniques with high spatial and temporal resolution overcome …
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Rapeseed (Brassica napus L.) Termination and Integration of Halauxifen into Virginia Cotton (Gossypium hirsutum L.) Production
… to its deep growing taproot which creates soil macropores and increases water infiltration. If not properly terminated rapeseed can become problematic due to its pod-shattering tendency and its difficulty to terminate with herbicides once it enters reproductive growth. Results indicate …
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Hydrologic Regime and Soil Property Interactions in a Forested Peatland
… Further, upper layers had higher proportions of macropores, resulting in an overall lower water retention capacity. These differences in layer properties suggest the upper layer is more susceptible to drying, increasing fire vulnerability, oxidation, and shifts in vegetation composition that do …
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A tour-de-force in polymer crosslinked aerogels
… with a high open mesoporosity. Nevertheless, macropores facilitate mass-transfer and they could be beneficial for applications in separations or as fuel cell and battery electrodes. Here, we report a method where an open macroporosity is introduced by pyrolysing RF aerogels whose skeletal …
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Evaluating Five Years of Soil Hydrologic Response Following the 2009 Lockheed Fire in the Coastal Santa Cruz Mountains of California
… rock fragments or in the presence of large soil macropores. It is recognized that additional understanding would be gained from having multiple replications at each site every year and tests could be conducted on a subwatershed scale to account for the naturally occurring variability of larger …
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Modification of the Field Moisture Balance Water Quality model (FMBWQ) to simulate subsurface drainage and preferential flow
… shows the preferential movement of water through macropores. Considering this, it was also deemed necessary to add a preferential flow subroutine to FMBWQ. Under these modeling conditions, the following specific objectives were laid out: 1) to improve or replace the existing tile flow subroutine …
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The Design of Hydrogel Polymers for Artificial Liver Support Systems.
… thereby creating a polymer matrix with large macropores running through it. These materials are interesting because of their greater permeability to large molecules, a property of interest if the dialytic method of removing blood toxins is considered. These materials did indeed show good …
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