Artículos de revistas: "Solute deposition"

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Piatek, K. B., S. F. Christopher y M. J. Mitchell. "Spatial and temporal dynamics of stream chemistry in a forested watershed impacted by atmospheric deposition". Hydrology and Earth System Sciences Discussions 5, n.º 4 (8 de septiembre de 2008): 2581–622. http://dx.doi.org/10.5194/hessd-5-2581-2008.

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Abstract. We analyzed spatial and temporal dynamics of solute chemistry in a forest watershed impacted by atmospheric deposition in the Adirondack Mountains of New York State, USA. Spatial dynamics of solute chemistry and natural abundance isotopes of nitrate (15N and 18O) were examined in 6 locations and the watershed outlet in 2001 and 2002. Temporal dynamics were examined during 5 discharge periods: winter, snowmelt, spring, summer, and fall, which were based on discharge levels at the outlet. Solute concentrations were statistically significantly different (p≤0.05) among stream sampling locations and discharge periods, with no interaction effects. Groundwater sources located in upper watershed controlled stream chemistry at higher elevations with highest pH, Ca2+, sum of base cations, Si, NO3-, total N, and SO42- and lowest Al concentrations. Two low elevation wetlands had a substantial influence over stream chemistry at those locations contributing lowest NO3-, total N, and highest DOC and DON. Snowmelt exhibited among the lowest pH, sum of base cations, and SO42-, and highest NO3-, total N, DON, and total Al; snowmelt appeared to dilute groundwater, and flush stored soil-derived solutes. Summer discharge, composed mainly of groundwater, exhibited the lowest flow, among the highest Mg2+, Ca2+, and lowest DON, DOC, and total Al concentrations. Isotopic analysis together with patterns of NH4+ versus NO3- dynamics indicated that NO3- was microbial, generated in fall and accumulated in winter in upper watershed soils, and flushed to stream during high discharge events. Highest discharge in snowmelt 2001, a summer drought in 2002, and fall storms following the drought were further evaluated for their specific effects on stream chemistry. Snowmelt 2001 had the lowest pH and highest NO3-, base flow during summer drought had the lowest total Al, and storms in fall 2002 had highest SO42- of all periods, but all other solute concentrations were comparable to other discharge periods in this study. Depending on objectives, watershed outlet alone may sufficiently represent solute dynamics in the watershed, and high-discharge events may sufficiently describe solute fluxes for the watershed.

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2

Sharp, Martin, Mark Skidmore y Peter Nienow. "Seasonal and spatial variations in the chemistry of a High Arctic supraglacial snow cover". Journal of Glaciology 48, n.º 160 (2002): 149–58. http://dx.doi.org/10.3189/172756502781831683.

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AbstractThis paper describes the physical and chemical properties of the snow- pack on John Evans Glacier, Ellesmere Island, Canadian Arctic Archipelago, and investigates the controls on snowpack solute concentrations and atmospheric deposition. The snowpack contains three layers that are traceable across the whole glacier. These represent fall accumulation that has been metamorphosed to depth hoar, winter accumulation mixed with snow reworked by wind from the underlying depth hoar, and spring accumulation mixed with wind-reworked snow. The seasonal cycle in snow chemistry closely reflects changes in the composition of the atmospheric aerosol at Alert, with some modification of NO3− concentrations by post-depositional processes. Mean water-weighted solute concentrations in the snowpack are largely independent of accumulation, while atmospheric deposition tends to increase with accumulation. This suggests that, for most species, wet deposition is the dominant depositional process throughout the year. However, concentrations of Ca2+ and K+ increase with both accumulation and elevation, implying an enhanced input from dry deposition of soil dust above 800 m elevation. Concentrations of SO42− are inversely related to accumulation, especially in the winter layer, suggesting a significant input from non-precipitating events, such as dry deposition or riming, during this period of very limited snowfall.

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3

Yde, Jacob C., Mette Riger-Kusk, Hanne H. Christiansen, N. Tvis Knudsen y Ole Humlum. "Hydrochemical characteristics of bulk meltwater from an entire ablation season, Longyearbreen, Svalbard". Journal of Glaciology 54, n.º 185 (2008): 259–72. http://dx.doi.org/10.3189/002214308784886234.

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AbstractThe ionic and isotopic characteristics of bulk waters emanating from the cold-based Longyearbreen, central Svalbard, in 2004 are examined to determine lithological, hydrological and glaciological controls on water composition, solute provenance and chemical denudation. The geology consisted of reactive coal seams and associated sedimentary rocks. Acidity caused by microbial-mediated oxidation of sulfides and, to a lesser extent, nitrogen-bearing minerals was neutralized by congruent dissolution of dolomite and incongruent weathering of silicates in open-system subglacial drainage channels. The ablation season was divided into an early melt season, a peak-flow period and a late melt season. The runoff distribution during these periods was 1.7%, 89.7% and 8.6%, respectively, whereas the solute flux distribution was 1.9%, 82.1% and 16.0%, respectively. Comparisons between different annual solute flux estimation methods indicated that extrapolation of peak-flow period data significantly underestimated both the early- and late-melt-season solute fluxes. About 3.8% of the solutes derived from sea-salt spray, 0.7% from acid aerosol deposition and 95.5% from crustal/organic sources. The physical and chemical conditions resulted in diffusion of CO2 rather than atmospheric drawdown. The cation-equivalent weathering rate and the crustal solute yield were 322 ΣmEq+m−2 a−1 and 22 t km−2 a−1, respectively, which are within the regional range of Svalbard. However, the chemical weathering intensity was as high as 940 ΣmEq+ m−3 owing to the relatively low specific discharge of 0.34 m a−1.

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4

Chin-Tai Chen, Ching-Chang Chieng y Fan-Gang Tseng. "Uniform Solute Deposition of Evaporable Droplet in Nanoliter Wells". Journal of Microelectromechanical Systems 16, n.º 5 (octubre de 2007): 1209–18. http://dx.doi.org/10.1109/jmems.2007.904327.

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5

Tanaka, Tadashi. "THE ROLE OF SUBSURFACE FLOW DYNAMIC ON SPATIAL AND TEMPORAL VARIATION OF WATER CHEMISTRY IN A HEADWATER CATCHMENT". Indonesian Journal of Agricultural Science 8, n.º 1 (25 de octubre de 2016): 17. http://dx.doi.org/10.21082/ijas.v8n1.2007.17-30.

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Variation of water chemistry does not merely occur due to in situ chemical process, but also transport process. The study was carried out to address the role of subsurface flow dynamic on spatial and temporal variation of water chemistry in a headwater catchment. Hydrometric and hydrochemistry measurements were done in transect with nested piezometers, tensiometers, and suction samplers at different depths across hillslope and riparian zone in a 5.2 ha first-order drainage of the Kawakami experimental basin, Nagano, Central Japan from August 2000 to August 2001. Spatial variation of solute concentration was defined by the standard deviation and coefficient of variation of the seasonal observed concentrations. Autocorrelation analysis was performed to define temporal variation of solute concentration. The results showed that spatial variation of water chemistry was mainly influenced by the variation of subsurface flow through the hillslope and riparian zone. Solute concentration in the deep riparian groundwater was almost three times higher than that in the hillslope segment. A prominent downward flow in deep riparian groundwater zone provided transport of solutes to the deeper layer. Time series analysis showed that in the deep riparian groundwater, Ca2+, Mg2+, SO42- and HCO3- concentrations underwent a random process, Na+ concentration of a random process superimposed by a trend process, and SiO2 of a random process superimposed by a periodic process. Near the riparian surface, SO42- concentration was composed of a random process superimposed by a periodic process, whereas other solutes were mainly in a random process. In the hillslope soil water, there was no trend observed for the Na+ concentration, but there were for Ca2+ and Mg2+. The magnitude and direction of subsurface flow across hillslope and riparian zone created transport and deposition processes that changed solute concentration spatially and temporally.

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6

Tanaka, Tadashi. "THE ROLE OF SUBSURFACE FLOW DYNAMIC ON SPATIAL AND TEMPORAL VARIATION OF WATER CHEMISTRY IN A HEADWATER CATCHMENT". Indonesian Journal of Agricultural Science 8, n.º 1 (25 de octubre de 2016): 17. http://dx.doi.org/10.21082/ijas.v8n1.2007.p17-30.

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Variation of water chemistry does not merely occur due to in situ chemical process, but also transport process. The study was carried out to address the role of subsurface flow dynamic on spatial and temporal variation of water chemistry in a headwater catchment. Hydrometric and hydrochemistry measurements were done in transect with nested piezometers, tensiometers, and suction samplers at different depths across hillslope and riparian zone in a 5.2 ha first-order drainage of the Kawakami experimental basin, Nagano, Central Japan from August 2000 to August 2001. Spatial variation of solute concentration was defined by the standard deviation and coefficient of variation of the seasonal observed concentrations. Autocorrelation analysis was performed to define temporal variation of solute concentration. The results showed that spatial variation of water chemistry was mainly influenced by the variation of subsurface flow through the hillslope and riparian zone. Solute concentration in the deep riparian groundwater was almost three times higher than that in the hillslope segment. A prominent downward flow in deep riparian groundwater zone provided transport of solutes to the deeper layer. Time series analysis showed that in the deep riparian groundwater, Ca2+, Mg2+, SO42- and HCO3- concentrations underwent a random process, Na+ concentration of a random process superimposed by a trend process, and SiO2 of a random process superimposed by a periodic process. Near the riparian surface, SO42- concentration was composed of a random process superimposed by a periodic process, whereas other solutes were mainly in a random process. In the hillslope soil water, there was no trend observed for the Na+ concentration, but there were for Ca2+ and Mg2+. The magnitude and direction of subsurface flow across hillslope and riparian zone created transport and deposition processes that changed solute concentration spatially and temporally.

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7

Gogoi, Prerona, Arun Chattopadhyay y Partho Sarathi Gooh Pattader. "Toward Controlling Evaporative Deposition: Effects of Substrate, Solvent, and Solute". Journal of Physical Chemistry B 124, n.º 50 (9 de diciembre de 2020): 11530–39. http://dx.doi.org/10.1021/acs.jpcb.0c08045.

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8

Bondesson, Eva, Thomas Bengtsson, Lars-Erik Nilsson y Per Wollmer. "Site of deposition and absorption of an inhaled hydrophilic solute". British Journal of Clinical Pharmacology 63, n.º 6 (junio de 2007): 722–31. http://dx.doi.org/10.1111/j.1365-2125.2006.02835.x.

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9

Lin, Jixiang, Xiaoyuan Peng, Xiaoyu Hua, Shengnan Sun, Yingnan Wang y Xiufeng Yan. "Effects of arbuscular mycorrhizal fungi on Leymus chinensis seedlings under salt–alkali stress and nitrogen deposition conditions: from osmotic adjustment and ion balance". RSC Advances 8, n.º 26 (2018): 14500–14509. http://dx.doi.org/10.1039/c8ra00721g.

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10

Shang, Yidan, Kiao Inthavong, Dasheng Qiu, Narinder Singh, Fajiang He y Jiyuan Tu. "Prediction of nasal spray drug absorption influenced by mucociliary clearance". PLOS ONE 16, n.º 1 (28 de enero de 2021): e0246007. http://dx.doi.org/10.1371/journal.pone.0246007.

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Evaluation of nasal spray drug absorption has been challenging because deposited particles are consistently transported away by mucociliary clearance during diffusing through the mucus layer. This study developed a novel approach combining Computational Fluid Dynamics (CFD) techniques with a 1-D mucus diffusion model to better predict nasal spray drug absorption. This integrated CFD-diffusion approach comprised a preliminary simulation of nasal airflow, spray particle injection, followed by analysis of mucociliary clearance and drug solute diffusion through the mucus layer. The spray particle deposition distribution was validated experimentally and numerically, and the mucus velocity field was validated by comparing with previous studies. Total and regional drug absorption for solute radius in the range of 1 − 110nm were investigated. The total drug absorption contributed by the spray particle deposition was calculated. The absorption contribution from particles that deposited on the anterior region was found to increase significantly as the solute radius became larger (diffusion became slower). This was because the particles were consistently moved out of the anterior region, and the delayed absorption ensured more solute to be absorbed by the posterior regions covered with respiratory epithelium. Future improvements in the spray drug absorption model were discussed. The results of this study are aimed at working towards a CFD-based integrated model for evaluating nasal spray bioequivalence.

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11

Jokinen, Ville, Sami Franssila y Marc Baumann. "Engineered droplets for dried droplet solute deposition by mass spectrometric imaging". Microfluidics and Nanofluidics 11, n.º 2 (5 de marzo de 2011): 145–56. http://dx.doi.org/10.1007/s10404-011-0781-x.

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12

Li, Xiaobao, David L. Chopp, William A. Russin, Paul T. Brannon, Matthew R. Parsek y Aaron I. Packman. "In SituBiomineralization and Particle Deposition Distinctively Mediate Biofilm Susceptibility to Chlorine". Applied and Environmental Microbiology 82, n.º 10 (4 de marzo de 2016): 2886–92. http://dx.doi.org/10.1128/aem.03954-15.

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ABSTRACTMicrobial biofilms and mineral precipitation commonly co-occur in engineered water systems, such as cooling towers and water purification systems, and both decrease process performance. Microbial biofilms are extremely challenging to control and eradicate. We previously showed thatin situbiomineralization and the precipitation and deposition of abiotic particles occur simultaneously in biofilms under oversaturated conditions. Both processes could potentially alter the essential properties of biofilms, including susceptibility to biocides. However, the specific interactions between mineral formation and biofilm processes remain poorly understood. Here we show that the susceptibility of biofilms to chlorination depends specifically on internal transport processes mediated by biomineralization and the accumulation of abiotic mineral deposits. Using injections of the fluorescent tracer Cy5, we show thatPseudomonas aeruginosabiofilms are more permeable to solutes afterin situcalcite biomineralization and are less permeable after the deposition of abiotically precipitated calcite particles. We further show that biofilms are more susceptible to chlorine killing after biomineralization and less susceptible after particle deposition. Based on these observations, we found a strong correlation between enhanced solute transport and chlorine killing in biofilms, indicating that biomineralization and particle deposition regulate biofilm susceptibility by altering biocide penetration into the biofilm. The distinct effects ofin situbiomineralization and particle deposition on biocide killing highlight the importance of understanding the mechanisms and patterns of biomineralization and scale formation to achieve successful biofilm control.

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13

Edwards, Aurélie, Mark J. Delong y Thomas L. Pallone. "Interstitial water and solute recovery by inner medullary vasa recta". American Journal of Physiology-Renal Physiology 278, n.º 2 (1 de febrero de 2000): F257—F269. http://dx.doi.org/10.1152/ajprenal.2000.278.2.f257.

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A recent model of volume and solute microvascular exchange in the renal medulla was extended by simulating the deposition of NaCl, urea, and water into the medullary interstitium from the loops of Henle and collecting ducts with generation rates that undergo spatial variation within the inner medullary interstitium. To build an exponential osmolality gradient in the inner medulla, as suggested by Koepsell et al. (H. Koepsell, W. E. A. P. Nicholson, W. Kriz, and H. J. Höhling. Pflügers Arch. 350: 167–184, 1974), the ratio of the interstitial area-weighted generation rate of small solutes to that of water must increase along the corticomedullary axis. We satisfied this condition either by holding the area-weighted generation rate of water constant while increasing that of NaCl and urea or by reducing the input rate of water with medullary depth. The latter case, in particular, yielded higher solute concentrations at the papillary tip. Assuming that the fraction of the filtered load recovered by inner medullary vasa recta for water, NaCl, and urea is 1%, 1%, and 40%, respectively, papillary tip osmolality is 1,470 mosmol/kgH2O when urea generation and NaCl generation per unit volume of interstitium increase exponentially and linearly, respectively. The inner medullary osmolar gradient also increases further when 1) medullary blood flow is reduced, 2) hydraulic conductivity of descending vasa recta (DVR) is lowered, and 3) vasa recta permeability to NaCl and urea is maximized. The coupling between water and small solute transport, resulting from aquaporin-1-mediated transcellular flux in DVR, also enhances tip osmolality.

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14

De Mora, S. J., R. F. Whitehead y M. Gregory. "Aqueous geochemistry of major constituents in the Alph River and tributaries in Walcott Bay, Victoria Land, Antarctica". Antarctic Science 3, n.º 1 (marzo de 1991): 73–86. http://dx.doi.org/10.1017/s0954102091000111.

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Two geochemical surveys of the major constituents of the Alph River, situated in Walcott Bay, Victoria Land, were undertaken in the austral summer of 1987–88. At the same time, tributaries and the runoff from various glaciers were investigated. The Alph River has an average total dissolved solids (TDS) concentration of 63.5 mgl−1, approximately half that of average world river water. The chemical composition is dominated by Na+ and HCO−3. Glacial melt waters have very low TDS but chemical weathering over the course of a few kilometres causes solute concentrations in the tributaries to exceed those of the Alph River. The composition of the streams is variable, but often Ca2+ is the principal cation. Enrichment factor and mass balance calculations indicate that the salts in the Alph River and its tributaries have a substantial non-marine component. Chemical weathering of calcite, mirabilite, gypsum and halite contribute solutes to the aquatic system. A “Gibbs Plot” [TDS versus Na:(Na+Ca) weight ratio] indicates that water samples from direct glacial runoff fall outside the world water envelope. They have low solute levels but enhanced Ca2+ concentrations, resulting from the aeolian deposition and subsequent dissolution of calcitic material.

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15

Mukherjee, Nillohit, Sk Faruque Ahmed, Kalyan Kumar Chattopadhyay y Anup Mondal. "Role of solute and solvent on the deposition of ZnO thin films". Electrochimica Acta 54, n.º 16 (junio de 2009): 4015–24. http://dx.doi.org/10.1016/j.electacta.2009.02.035.

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16

Martínez, F., A. Martín, P. Prádanos, J. I. Calvo, L. Palacio y A. Hernández. "Protein Adsorption and Deposition onto Microfiltration Membranes: The Role of Solute–Solid Interactions". Journal of Colloid and Interface Science 221, n.º 2 (enero de 2000): 254–61. http://dx.doi.org/10.1006/jcis.1999.6575.

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17

He, Xiuli, Lijun Song, Gang Yu y Jyoti Mazumder. "Solute transport and composition profile during direct metal deposition with coaxial powder injection". Applied Surface Science 258, n.º 2 (noviembre de 2011): 898–907. http://dx.doi.org/10.1016/j.apsusc.2011.09.023.

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18

How, Mok Tze y Mazrul Nizam Abu Seman. "Fabrication of PSS/PDADMAC Polyelectrolyte Membrane via Layer-by-Layer (LbL) Technique for Forward Osmosis (FO) Application". Key Engineering Materials 797 (marzo de 2019): 13–19. http://dx.doi.org/10.4028/www.scientific.net/kem.797.13.

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In this study, FO membrane was fabricated by Layer-by-Layer (LbL) coating technique using Poly (sodium 4-styrene-sulfonate)(PSS) and Poly (diallyl-dimethylammoniumchloride) (PDADMAC) as the active polyelectrolytes. Different concentrations of polyelectrolytes and deposition time of polyelectrolytes were investigated. The success of the coated layer was confirmed using ATR-FTIR and FESEM images. The membrane performance was determined by water flux and reverse solute diffusion (RSD) using pure water and 1.75M Na2SO4 as feed and draw solution, respectively. It was observed that the highest water flux, 6.76 L/ was recorded at the lowest polyelectrolytes concentration and longer deposition time. Meanwhile, the minimum RSD was achieved by the membrane fabricated at the longest deposition time and highest polyelectrolyte concentration.

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19

Charcosset, Catherine, F. Yousefian, J. F. Thovert y P. M. Adler. "Calculation of flow and solute deposition through three-dimensional reconstructed model of microporous membranes". Desalination 145, n.º 1-3 (septiembre de 2002): 133–38. http://dx.doi.org/10.1016/s0011-9164(02)00398-3.

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20

Asbury, Clyde E., William H. McDowell, Roberto Trinidad-Pizarro y Samuel Berrios. "Solute deposition from cloud water to the canopy of a puerto rican montane forest". Atmospheric Environment 28, n.º 10 (junio de 1994): 1773–80. http://dx.doi.org/10.1016/1352-2310(94)90139-2.

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21

Zimmermann, Alexander, Sonja Germer, Christopher Neill, Alex V. Krusche y Helmut Elsenbeer. "Spatio-temporal patterns of throughfall and solute deposition in an open tropical rain forest". Journal of Hydrology 360, n.º 1-4 (octubre de 2008): 87–102. http://dx.doi.org/10.1016/j.jhydrol.2008.07.028.

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22

Guan, H., A. J. Love, C. T. Simmons, O. Makhnin y A. S. Kayaalp. "Factors influencing chloride deposition in a coastal hilly area and application to chloride deposition mapping". Hydrology and Earth System Sciences 14, n.º 5 (26 de mayo de 2010): 801–13. http://dx.doi.org/10.5194/hess-14-801-2010.

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Abstract. Chloride is commonly used as an environmental tracer for studying water flow and solute transport in the environment. It is especially useful for estimating groundwater recharge based on the commonly used chloride mass balance (CMB) method. Strong spatial variability in chloride deposition in coastal areas is one difficulty encountered in appropriately applying the method. A high-resolution bulk chloride deposition map in the coastal region is thus needed. The aim of this study is to construct a chloride deposition map in the Mount Lofty Ranges (MLR), a coastal hilly area of approximately 9000 km2 spatial extent in South Australia. We examined geographic (related to coastal distance), orographic, and atmospheric factors that may influence chloride deposition, using partial correlation and regression analyses. The results indicate that coastal distance, elevation, as well as terrain aspect and slope, appear to be significant factors controlling chloride deposition in the study area. Coastal distance accounts for 70% of spatial variability in bulk chloride deposition, with elevation, terrain aspect and slope an additional 15%. The results are incorporated into a de-trended residual kriging model (ASOADeK) to produce a 1 km×1 km resolution bulk chloride deposition and concentration maps. The average uncertainty of the deposition map is about 20–30% in the western MLR, and 40–50% in the eastern MLR. The maps will form a useful basis for examining catchment chloride balance for the CMB application in the study area.

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23

Li, Shiju, Bowen Wei, Wei Yu, Chen He, Yong Li, Guangming Xu y Zhaodong Wang. "Mechanism of Electromagnetic Field in the Sub-RapidSolidification of High-Strength Al-Cu-Li Alloy Produced by Twin-Roll Casting". Metals 11, n.º 6 (11 de junio de 2021): 952. http://dx.doi.org/10.3390/met11060952.

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In this work, a Al-Cu-Li alloy plate with outstanding mechanical properties was successfully prepared with electromagnetic twin-roll casting (TRC) technology. The microstructure of Al-Cu-Li alloy manufactured by conventional mold casting, TRC, and electromagnetic TRC was studied in detail. The action mechanism of electromagnetic oscillation field (EOF) in the TRC process was studied by systematic experimental characterization and numerical simulation. The results show that the EOF will enlarge the circumfluence area in the cast-rolling zone, accelerate the mass transfer and heat transfer in the molten pool, and make the solute field and flow field in the liquid cavity tend to be evenly distributed. Further, the introduction of the EOF will produce the electromagnetic body force F with the maximum strength of 14 N/m3. The F acting on the solidification front will eliminate the accumulation and deposition of Cu2+, Li+, Mg2+, Zn2+, Mn2+ at the dendrite tip and inhibit the growth of dendrites. At the same time, the F can refine the microstructure of the TRC plate, promote the formation of equiaxed crystals, improve the supersaturated solid solubility of solute elements in the α(Al) matrix, and avoid the appearance of obvious solute segregation area or the formation of excessive solute enrichment area. Therefore, the macro-segregation in TRC plate was significantly reduced, the solidification structure was dramatically refined, and the comprehensive properties of the alloy were remarkably improved.

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Guan, H., A. J. Love, C. T. Simmons y A. S. Kayaalp. "Factors influencing chloride deposition in a coastal hilly area and application to chloride deposition mapping". Hydrology and Earth System Sciences Discussions 6, n.º 5 (16 de septiembre de 2009): 5851–80. http://dx.doi.org/10.5194/hessd-6-5851-2009.

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Abstract. Chloride is commonly used as an environmental tracer for studying water flow and solute transport in the environment. It is especially useful for estimating groundwater recharge based on the commonly used chloride mass balance (CMB) method. Strong spatial variability in chloride deposition in coastal areas is one difficulty encountered in appropriately applying the CMB approach. Furthermore, intensive vegetation clearance for agriculture, for example during the European settlement in many coastal areas of Australia, may have perturbed catchment chloride balance conditions for appropriate use in CMB applications. In order to deal with these issues, a high resolution chloride deposition map in the coastal region is needed. In this study, we examined geographic, orographic, and atmospheric factors influencing chloride deposition in the Mount Lofty Ranges (MLR), a coastal hilly area of approximately 9000 km2 spatial extent in South Australia, using partial correlation and regression analyses. The results indicate that coastal distance, and terrain aspect and slope are two most significant factors controlling chloride deposition. Coastal distance accounts for 65% spatial variability in chloride deposition, with terrain aspect and slope for 8%. The deposition gradient is about 0.08 gm-2 year-1 km-1 as one progresses inland. The results are incorporated into a published de-trended residual kriging approach (ASOADeK) to produce a 1 km×1 km resolution annual chloride deposition map and a bulk precipitation chloride concentration map. The average uncertainty of the deposition map is about 30% in the western MLR, and over 50% in the eastern MLR. The maps will form a very useful basis for examining catchment chloride balances for use in the CMB application in the study area.

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25

Saeed, Waleed, Orfan Shouakar-Stash, Warren Wood, Beth Parker y André Unger. "Groundwater and Solute Budget (A Case Study from Sabkha Matti, Saudi Arabia)". Hydrology 7, n.º 4 (3 de diciembre de 2020): 94. http://dx.doi.org/10.3390/hydrology7040094.

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Sabkha Matti is the largest inland sabkha (2950 km2) in the Arabian Peninsula. The drainage area supporting this sabkha is >250,000 km2 and is the discharge point for part of the ten thousand meter thick regional groundwater systems ranging in age from Precambrian through Miocene in the Rub’ al Khali structural basin. A hydrologic budget was constructed for this sabkha, where water fluxes were calculated on the basis of hydraulic gradient and conductivities measured in both shallow and deep wells. The evaporation rates from the surface of the sabkha were estimated from the published data and indicate that almost all the annual rainfall is lost by surface evaporation. The water flux multiplied by its solute concentration showed that nearly all the solutes in the sabkha were derived by upward leakage from the underlying regional aquifers rather than the weathering of the aquifer framework, from precipitation, or from other sources. Steady-state estimates within a rectilinear control volume of the sabkha indicate that about 1 m3/year of water enters by lateral groundwater flow, 2 m3/year of water exits by lateral groundwater flow, 20 m3/year enters by upward leakage, 780 m3/year enters by recharge from rainfall, and 780 m3/year is lost by evaporation. The proposed conceptual model of the hydrology for sabkha Matti is assumed to apply to the rest of the inland sabkhas of the Arabia Peninsula and to many ancient environments of deposition observed in the geologic record.

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26

Takeda, F., M. Wisniewski y D. M. Glenn. "CRYO-SEM OBSERVATION OF OCCLUSIONS IN STRAWBERRY HYDATHODES". HortScience 25, n.º 9 (septiembre de 1990): 1089c—1089. http://dx.doi.org/10.21273/hortsci.25.9.1089c.

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In previous work no difference was found in leaf water potential or solute potential between young guttating leaves and older non-guttating leaves of the same plant. This suggested that the absence of guttation in older leaves was associated with a plant resistance component in the hydathodes. Hydathodes of young, folded leaves contained water pores with various apertures and no signs of occlusion.. In expanded, young leaves, production of epicuticular waxes and excretion of some substance through the pores was observed in the hydathode region. By the time leaves had fully expanded the hydathodes had become brownish. The combination of wax deposition and excreted substance had formed plates of solid material covering water pores. These observations suggest that deposition of substances on top of pores contribute to occlusion of water pores in old leaves.

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27

Pritchard, Jeremy, A. Deri Tomos, John F. Farrar, Peter E. H. Minchin, Nick Gould, Matthew J. Paul, Elspeth A. MacRae, Richard A. Ferrieri, Dennis W. Gray y Michael R. Thorpe. "Turgor, solute import and growth in maize roots treated with galactose". Functional Plant Biology 31, n.º 11 (2004): 1095. http://dx.doi.org/10.1071/fp04082.

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It has been observed that extension growth in maize roots is almost stopped by exposure to 5 mm d-galactose in the root medium, while the import of recent photoassimilate into the entire root system is temporarily promoted by the same treatment. The aim of this study was to reconcile these two apparently incompatible observations. We examined events near the root tip before and after galactose treatment since the tip region is the site of elongation and of high carbon deposition in the root. The treatment rapidly decreased root extension along the whole growing zone. In contrast, turgor pressure, measured directly with the pressure probe in the cortical cells of the growing zone, rapidly increased by 0.15 MPa within the first hour following treatment, and the increase was maintained over the following 24 h. Both tensiometric measurements and a comparison of turgor pressure with local growth rate demonstrated that a rapid tightening of the cell wall caused the reduction in growth. Single cell sampling showed cell osmotic pressure increased by 0.3 MPa owing to accumulation of both organic and inorganic solutes. The corresponding change in cell water potential was a rise from –0.18 MPa to approximately zero. More mature cells at 14 mm from the root tip (just outside the growing region) showed a qualitatively similar response. Galactose treatment rapidly increased the import of recently fixed carbon (RFC) into the whole root as deduced by 11C labelling of photoassimilate. In contrast, there was a significant decrease in import of recently fixed carbon into the apical 5mm concomitant with the increase in turgor in this region. No decrease in import of recently fixed carbon was observed 5–15 mm from the root tip despite the increase in cortical cell turgor. These data are consistent with direct symplastic connections between the growing cells and the phloem supplying the solutes in the apical, but not the basal, regions of the growing zone. Hence, the inhibition of growth and the elevation of solute import induced by galactose are spatially separated within the root.

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28

Flessner, Michael F. "The Role of Extracellular Matrix in Transperitoneal Transport of Water and Solutes". Peritoneal Dialysis International: Journal of the International Society for Peritoneal Dialysis 21, n.º 3_suppl (diciembre de 2001): 24–29. http://dx.doi.org/10.1177/089686080102103s04.

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♦ Objective To define the extracellular matrix (ECM), to discuss the physical properties of its components and their impact on transport, and to review data in humans and in animals on the importance of hyaluronan to peritoneal dialysis. ♦ Methods Literature survey. ♦ Results The ECM fills the interstitium between parenchymal cells and blood vessels in the subperitoneal interstitium. It is responsible for the interstitial resistance to solute and water transfer through the peritoneal barrier. Major components are collagen and hyaluronan, which are synthesized locally in the peritoneal tissue. Synthesis and deposition of these components increase with inflammation, and concentrations of the components influence the mechanical properties of the tissue and the interstitial Starling forces as well as transport. Removal of hyaluronan appears to increase the rates of water and large-solute transport. Addition of hyaluronan to dialysate appears to enhance fluid recovery and to reduce protein loss. ♦ Conclusion Many of the physicochemical properties of ECM components are well described, but a large knowledge gap remains concerning the in vivo consequences of specific alterations in the interstitial components. More research is needed.

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29

Anderson, A. E., M. Weiler, Y. Alila y R. O. Hudson. "Dye staining and excavation of a lateral preferential flow network". Hydrology and Earth System Sciences 13, n.º 6 (29 de junio de 2009): 935–44. http://dx.doi.org/10.5194/hess-13-935-2009.

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Abstract. Preferential flow paths have been found to be important for runoff generation, solute transport, and slope stability in many areas around the world. Although many studies have identified the particular characteristics of individual features and measured the runoff generation and solute transport within hillslopes, very few studies have determined how individual features are hydraulically connected at a hillslope scale. In this study, we used dye staining and excavation to determine the morphology and spatial pattern of a preferential flow network over a large scale (30 m). We explore the feasibility of extending small-scale dye staining techniques to the hillslope scale. We determine the lateral preferential flow paths that are active during the steady-state flow conditions and their interaction with the surrounding soil matrix. We also calculate the velocities of the flow through each cross-section of the hillslope and compare them to hillslope scale applied tracer measurements. Finally, we investigate the relationship between the contributing area and the characteristics of the preferential flow paths. The experiment revealed that larger contributing areas coincided with highly developed and hydraulically connected preferential flow paths that had flow with little interaction with the surrounding soil matrix. We found evidence of subsurface erosion and deposition of soil and organic material laterally and vertically within the soil. These results are important because they add to the understanding of the runoff generation, solute transport, and slope stability of preferential flow-dominated hillslopes.

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30

Anderson, A. E., M. Weiler, Y. Alila y R. O. Hudson. "Dye staining and excavation of a lateral preferential flow network". Hydrology and Earth System Sciences Discussions 5, n.º 2 (15 de abril de 2008): 1043–65. http://dx.doi.org/10.5194/hessd-5-1043-2008.

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Abstract. Preferential flow features have been found to be important for runoff generation, solute transport, and slope stability in many areas around the world. Although many studies have identified the particular characteristics of individual features and measured the runoff generation and solute transport within hillslopes, no studies have determined how individual features are hydraulically connected at a hillslope scale. In this study, we used dye staining and excavation to determine the morphology and spatial pattern of a preferential flow network over a large scale (30 m). We explore the feasibility of extending small-scale dye staining techniques to the hillslope scale. We determine the lateral preferential flow features that are active during the steady state flow conditions and their interaction with the surrounding soil matrix. We also calculate the velocities of the flow through each cross-section of the hillslope and compare them to hillslope scale applied tracer measurements. Finally, we investigate the relationship between the contributing area and the characteristics of the preferential features. The experiment revealed that larger contributing areas coincided with highly developed and hydraulically connected preferential features that had flow with little interaction with the surrounding soil matrix. We found evidence of subsurface erosion and deposition of soil and organic material laterally and vertically within the soil. These results are important because they add to the understanding of the runoff generation, solute transport, and slope stability of these types of hillslopes.

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31

Nesbitt, Bruce E. y Walter Prochaska. "Solute chemistry of inclusion fluids from sparry dolomites and magnesites in Middle Cambrian carbonate rocks of the southern Canadian Rocky Mountains". Canadian Journal of Earth Sciences 35, n.º 5 (1 de mayo de 1998): 546–55. http://dx.doi.org/10.1139/e98-006.

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Middle Cambrian carbonate rocks of the southern Canadian Rocky Mountains are host to widespread units of white, sparry, hydrothermal, replacement, and open-space filling dolomite. Contained within the dolomites are occurrences of talc and Mississippi Valley type Pb-Zn (the former Kicking Horse and Monarch mines) mineralization and economic concentrations of magnesite (Mount Brussilof mine). Results of studies of solute chemistry of saline (18-25 equivalent wt.% NaCl) inclusion fluids reveal distinctly low Na/Br (55-220) and Cl/Br (95-340) values. These values indicate that the brines which formed the dolomite originated from seawater that had deposited large amounts of halite in an evaporitic environment. Low I/Br ratios for the dolomite-magnesite inclusion fluids are consistent with their derivation from seawater and contrast sharply with the high I/Br ratios of Laramide-age fluids, which formed veins throughout the Rocky Mountains. Variations in F/Br ratios between texturally early and late magnesites indicate the involvement of a second fluid in the formation of the late magnesites. Results of the study of solute chemistry of inclusion fluids from hydrothermal dolomites, magnesites, and associated mineralization are consistent with a model of the pre-Laramide formation of these materials from seawater that had undergone extensive evaporation and halite deposition. Distinct differences in I/Br, total salinity, and delta D values between the dolomite-magnesite depositing fluids and Laramide-age vein-forming fluids clearly indicate the lack of the involvement of Laramide-age fluids in the genesis of the dolomites, magnesites, and associated mineralization.

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32

Kousaka, Y., T. Niida, Y. Tanaka, Y. Sato, H. Kano, N. Fukushima y H. Sato. "Development of a New Continuous Monitor for Nonvolatile Solute in Ultrapure Water by Atomization". Journal of the IEST 30, n.º 4 (1 de julio de 1987): 39–42. http://dx.doi.org/10.17764/jiet.1.30.4.q03m5684126921nq.

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A new monitoring system has been developed for continuously measuring the concentration of total nonvolatile impurities in ultrapure water. The measuring method is based on the principle of determining the Residue After Evaporation (RAE) of atomized droplets, taking account of the particle deposition loss. The system consists of a water atomizing unit, a droplet evaporating and drying unit, an air diluter, a fine particle counter, etc. For the particle counter, a Condensation Nucleus Counter (CMC) is used; this counter is a mixing type, able to detect particles larger than 0.01 μm. It is verified from both the theoretical analysis and the experimental results that this monitor can rapidly detect very low impurity concentrations by counting the number concentration of aerosol particles.

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33

Wang, Hui, Jin Wang, Dan-dan Yang, Zong-li Liu, Yong-qing Zeng y Wei Chen. "Expression of lipid metabolism genes provides new insights into intramuscular fat deposition in Laiwu pigs". Asian-Australasian Journal of Animal Sciences 33, n.º 3 (1 de marzo de 2020): 390–97. http://dx.doi.org/10.5713/ajas.18.0225.

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Objective: The objective of this study was to measure the special expression pattern of lipid metabolism genes and investigate the molecular mechanisms underlying intramuscular fat (IMF) deposition in Longissimus dorsi muscle of Laiwu pigs.Methods: Thirty-six pigs (Laiwu n = 18; Duroc×Landrace×Yorkshire n = 18) were used for the measurement of the backfat thickness, marbling score, IMF content, and expression of lipid metabolism genes.Results: Significant correlations were found between IMF content and the mRNA expression of lipid metabolism genes. Of the 14 fat deposition genes measured, fatty acid synthase (FASN) showed the strongest correlation (r = 0.75, p = 0.001) with IMF content, and of the 6 fat removal genes, carnitine palmitoyl transferase 1B (CPT1B) exhibited the greatest negative correlation (r = –0.66, p = 0.003) with IMF content in Laiwu pig. Multiple regression analysis showed that CPT1B, FASN, solute carrier family 27 member 1 (SLC27A1), and fatty acid binding protein 3 (FABP3) contributed 38% of the prediction value for IMF content in Laiwu pigs. Of these four variables, CPT1B had the greatest contribution to IMF content (14%) followed by FASN (11%), SLC27A1 (9%), and FABP3 (4%).Conclusion: Our results indicate that the combined effects of an upregulation in fat deposition genes and downregulation in fat removal genes promotes IMF deposition in Laiwu pigs.

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34

Ugucioni, J. C. y M. Mulato. "Influence of deposition temperature, solvent, and solute concentration on the deposition mechanisms and final structure of mercury iodide fabricated using the spray pyrolysis technique". Journal of Applied Physics 100, n.º 4 (15 de agosto de 2006): 043506. http://dx.doi.org/10.1063/1.2225992.

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35

Wang, Yi-Ning y Chuyang Y. Tang. "Nanofiltration Membrane Fouling by Oppositely Charged Macromolecules: Investigation on Flux Behavior, Foulant Mass Deposition, and Solute Rejection". Environmental Science & Technology 45, n.º 20 (15 de octubre de 2011): 8941–47. http://dx.doi.org/10.1021/es202709r.

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36

Macis, Salvatore, Giannantonio Cibin, Valter Maggi, Giovanni Baccolo, Dariush Hampai, Barbara Delmonte, Alessandro D’Elia y Augusto Marcelli. "Microdrop Deposition Technique: Preparation and Characterization of Diluted Suspended Particulate Samples". Condensed Matter 3, n.º 3 (16 de julio de 2018): 21. http://dx.doi.org/10.3390/condmat3030021.

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The analysis of particulate matter (PM) in dilute solutions is an important target for environmental, geochemical, and biochemical research. Here, we show how microdrop technology may allow the control, through the evaporation of small droplets, of the deposition of insoluble materials dispersed in a solution on a well-defined area with a specific spatial pattern. Using this technology, the superficial density of the deposited solute can be accurately controlled. In particular, it becomes possible to deposit an extremely reduced amount of insoluble material, in the order of few μg on a confined area, thus allowing a relatively high superficial density to be reached within a limited time. In this work, we quantitatively compare the microdrop technique for the preparation of particulate matter samples with the classical filtering technique. After having been optimized, the microdrop technique allows obtaining a more homogeneous deposition and may limit the sample amount up to a factor 25. This method is potentially suitable for many novel applications in different scientific fields such as demanding spectroscopic studies looking at the mineral fraction contained in ice cores or to pollution investigations looking at the detection of heavy metals present in ultra-trace in water.

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37

Berger, Torsten W. y Gerhard Glatzel. "Canopy leaching, dry deposition, and cycling of calcium in Austrian oak stands as a function of calcium availability and distance from a lime quarry". Canadian Journal of Forest Research 28, n.º 9 (1 de septiembre de 1998): 1388–97. http://dx.doi.org/10.1139/x98-123.

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Three Austrian oak stands were chosen along a 4-km distance gradient from a lime quarry to study effects of Ca availability both on dry deposition rates and on Ca cycling in these ecosystems. A fourth stand was used as a more regional reference site, some 30 km west of the lime quarry. Calcium bulk precipitation fluxes decreased with increasing distance from the lime quarry, contributing to major differences in available Ca along the transect over the last decades. Higher supply of Ca changed biogeochemical cycling by increasing pool sizes and fluxes of Ca in foliage, litter, throughfall, forest floor, soil, herbaceous vegetation, and soil solution. Regression analyses of net throughfall was a useful tool for separating between dry deposition and leaching of Ca. Dry deposition rates of particulate Ca declined rapidly with increasing distance from the Ca source. Leaching of Ca from the canopy declined along the gradient according to Ca content of the green foliage during the growing season. Leaching rates as a percentage of the stand's annual requirement indicated a relative shift from solid (litter) toward more solute Ca fluxes reaching the forest floor with increasing Ca availability of the stand.

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38

Lin, Wei, Zhonghao Wang, Wei Wang, Qi Chen, Jianmin Xu y Jiuyang Yu. "Comparative analysis the performance of electrochemical water softening between high frequency electric fields and direct current electric fields based on orthogonal experimental methods". Water Science and Technology 83, n.º 7 (24 de febrero de 2021): 1677–90. http://dx.doi.org/10.2166/wst.2021.084.

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Abstract Electrochemical water softening has been widely used in industrial circulating cooling water systems; however, their low deposition efficiency is the main drawback that limits usage in medium to large enterprises. In this work, the effect of different parameters on the hardness removal efficiency and energy consumption of the electrochemical water softening system is experimentally studied, and the performance of water softening applied by high frequency electric fields and direct current electric fields are comparative analyzed. The impact factors of the electrochemical water softening system are as follows: initial feed concentration of solute, magnitude of voltage, inter-electrode distance, area of cathode and frequency of power supply. To improve the analysis efficiency, the L25 (55) orthogonal table is used to investigate the five different factors at five levels. The experimental results are shown that the initial feed concentration of solute is the most significant factor affecting the hardness removal efficiency. The optimal combination for water softening in the group applied by high frequency electric field and direct current electric field are A3B2C1D4E3 and A2B5C3D1 respectively. The energy utilization of the device applied by high frequency electric field is 3.2 times that applied by direct current electric field. The practice shows that direct current electric fields have a better softening effect, and are is more suitable for scaling ion removal. Particle image velocimetry (PIV) was used to observe the flow field induced by the electrolysis and found that the vertical and horizontal velocities of the flow field at low voltage are conducive to the migration of scaled ions to the cathode, and then the electrolytic reaction and deposition reaction synergy effect is the optimal.

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39

Leeuwenburgh, Sander C. G., M. C. Heine, Joop G. C. Wolke, Sotiris E. Pratsinis, J. Schoonman y John A. Jansen. "Correlating Electrospray Characteristics with Surface Morphology of Calcium Phosphate Coatings Deposited Using Electrostatic Spray Deposition (ESD)". Key Engineering Materials 309-311 (mayo de 2006): 611–14. http://dx.doi.org/10.4028/www.scientific.net/kem.309-311.611.

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In situ measurements of electrospray droplet sizes and velocities were performed by Phase Doppler Anemometry during Electrostatic Spray Deposition (ESD) of calcium phosphate (CaP) coatings. Numerous processing parameters were varied (nozzle-to-substrate distance, deposition temperature, nozzle geometry, and composition of the precursor solution), whereafter the morphological characteristics of these ESD-derived CaP coatings were correlated with measured droplet characteristics. Equal droplet sizes and velocities were measured for nozzle-to-substrate distances up to 40 mm and deposition temperatures up to 400 °C, indicating that electrospray droplets did not shrink at all during droplet flight using an involatile solvent butyl carbitol with a high boiling point (Tb = 231 °C). Nevertheless, coatings with considerably different surface morphologies were obtained under these conditions, varying from microporous structures with coalesced pore walls to morphologies revealing isolated rings on top of dense or grainy underlayers. The chemical composition of the precursor solutions and the mixing characteristics of the calcium and phosphate precursor components strongly influenced the initial droplet sizes, precipitation kinetics of the CaP solute, and subsequent coating morphology. Unique, reticular coating morphologies were deposited at a deposition rate of 3.2 µm/hour, which have a graded structure consisting of a dense underlayer, a submicron-porous intermediate layer, and a roughened toplayer revealing droplet-derived features such as isolated rings or coalesced, hollow surface pits.

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40

Rasmussen, Lars Holm, Vibeke Ernstsen y Hans Christian Bruun Hansen. "Redoximorphic Macropore Environments in an Agrudalf". Hydrology Research 32, n.º 4-5 (1 de agosto de 2001): 333–52. http://dx.doi.org/10.2166/nh.2001.0019.

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Soil materials in fracture walls may strongly interact with solutes and colloidal particles during preferential flow. Wall coatings rich in metal oxides, clays, and organic matter may increase sorption capacities, whereas coatings devoid of these constituents have the opposite effect of increasing the risk of leaching of otherwise strongly sorbing solutes. The contrasting compositions between bulk horizon and fracture wall materials of a Typic Agrudalf excavated at Flakkebjerg, Denmark, were studied by using chemical and micromorphological methods. In the upper 220 cm of the profile, the predominant desiccation and shear fractures had 2-30 mm thick hypocoatings depleted of Fe-oxides with adjacent 5-20 mm thick quasi-coatings containing 5-6 times as much Fe-oxide. Thin hypocoatings covering walls of smaller voids and surfaces of sand particles and with strong enrichments of Fe- and Mn-oxides occurred throughout the profile, but were most abundant below 220 cm. Fracture walls, commonly with distinct laminas of clay, silt, and organic matter, generally had slightly coarser texture, but were enriched in smectite compared with horizon materials. Higher contents of organic C in fracture coatings were attributed to root growth and deposition of A-horizon materials. Despite removal of Fe-oxides from depletion hypocoatings, no corresponding depletion of P was observed. However, calculations demonstrated that, in the case of macropore transport only, P sorption capacity would be at least 5 times less than during piston-like matrix flow. For adequate estimations of solute leaching from macroporous soils there is a strong need to properly take into account sorption properties of macropore wall materials!

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41

Forti, M. Cristina, Christine Bourotte, Valdir de Cicco, Francisco C. S. Arcova y Maurício Ranzini. "Fluxes of solute in two catchments with contrasting deposition loads in Atlantic Forest (Serra do Mar/SP-Brazil)". Applied Geochemistry 22, n.º 6 (junio de 2007): 1149–56. http://dx.doi.org/10.1016/j.apgeochem.2007.03.006.

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42

Shamsuddin, Norazanita, Chengcheng Cao, Victor M. Starov y Diganta Bhusan Das. "A comparative study between stirred dead end and circular flow in microfiltration of China clay suspensions". Water Supply 16, n.º 2 (30 de octubre de 2015): 481–92. http://dx.doi.org/10.2166/ws.2015.158.

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A well-defined comparative study between stirred dead end and circular crossflow for microfiltration of china clay suspensions has been undertaken. The comparisons have been made with respect to convective mass transfer coefficients, permeation and rejection rates, and energy consumption. Similar operating and hydrodynamic conditions were implemented for the comparison. According to our experimental data the circular crossflow module was proven to perform better as compared with the stirred dead end system due to the higher mass transfer coefficients, higher permeation rates and lower energy consumption. The mass transfer coefficients observed are comparable to those previously found in vortex flow filtration and dead end flow filtration. The presence of Dean vortices in the circular crossflow module promotes flow instabilities in the curved channel flow path which reduce the concentration polarization effect during the filtration process. The concentration polarization effect however deteriorated due to solute build up (high solute concentration at the membrane surface) and decrease of the shear stress, i.e., the particle lift forces on the membrane surface. This resulted in deposition of particles on the membrane surface. In terms of energy consumption, for the same energy cost the limiting flux reached in circular crossflow was found to be higher than in the stirred dead end unit.

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43

Chen, J. P., A. Hazra y Z. Levin. "Parameterizing ice nucleation rates for cloud modeling using contact angle and activation energy derived from laboratory data". Atmospheric Chemistry and Physics Discussions 8, n.º 4 (29 de julio de 2008): 14419–65. http://dx.doi.org/10.5194/acpd-8-14419-2008.

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Abstract. The rate of ice nucleation in clouds is not easily determined and large discrepancies exist between model predictions and actual ice crystal concentration measured in clouds. In an effort to improve the parameterization of ice nucleating in cloud models, we investigate the rate of heterogeneous ice nucleation under specific ambient conditions by knowing the sizes as well as two thermodynamic parameters of the ice nuclei – contact angle and activation energy. Laboratory data of freezing and deposition nucleation modes were analyzed to derive inversely the two thermodynamic parameters for a variety of ice nuclei, including mineral dusts, bacteria, pollens, and soot particles. The analysis considered the Zeldovich factor for the adjustment of ice germ formation, as well as the solute and curvature effects on surface tension, the latter effects have strong influence on the contact angle. Contact angle turns out to be a more important factor than the activation energy in discriminating the nucleation capabilities of various ice nuclei species. By extracting these thermodynamic parameters, laboratory results can be converted into a formulation that follows classical nucleation theory, which then has the flexibility of incorporating factors such as the solute effect and curvature effect that were not considered in the experiments.

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44

Grinsven, J. J. M. van, J. Kros, N. van Breemen, W. H. van Riemsdijk y E. van Eek. "Simulated response of an acid forest soil to acid deposition and mitigation measures." Netherlands Journal of Agricultural Science 37, n.º 4 (1 de diciembre de 1989): 279–99. http://dx.doi.org/10.18174/njas.v37i4.16614.

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A modified version of the soil-water acidification model ILWAS was applied to an acid forest soil in the 'Hackfort' experimental forest in the Netherlands. Monthly observations of the chemistry of atmospheric and soil water between April 1981 and April 1987 were used. ILWAS overestimated water uptake reduction, which caused overestimation of soil water fluxes by 20%, compared with values predicted by the hydrological model SWATRE. ILWAS does not simulate capillary rise which may lead to overestimation of solute concentrations. Chemical calibration of the ILWAS model to field data was mainly confined to adjustment of the rate constants for nitrification and gibbsite dissolution. Calibration of these rate constants was complicated by effects of cation exchange. ILWAS was too crude to simulate the N-dynamics, which led to a relatively strong variation of simulated NO3 concentration near the end of the growing season. After calibration the ILWAS model was used to predict the effects of 50% reduction of (NH4)2SO4 deposition, of a fertilization experiment with 2.6 kmolc/ha K2SO4 and 8.6 kmolc/ha MgSO4, and of removal of the forest vegetation. (Abstract retrieved from CAB Abstracts by CABI’s permission)

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45

Wang, Jianfu, Xin Kang y Chunyin Peng. "Modelling and Experimental Investigation on the Settling Rate of Kaolinite Particles in Non-Ideal Sedimentation Stage under Constant Gravity". Materials 13, n.º 17 (27 de agosto de 2020): 3785. http://dx.doi.org/10.3390/ma13173785.

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We compared the catalytic effects of two polymers (soluble starch and apple pectin) on the flocculation of kaolinite suspension. Moreover, the relationship between the zeta potential value and the time when kaolin particle sedimentation occurred was verified, and the mechanism of flocculation was analyzed. Additionally, a constitutive model was proposed to simulate the non-ideal sedimentation of clay particles in an aqueous system under constant gravity. This model not only considers the inhomogeneity of the solute but also simulates the change in clay concentration with time during the deposition process. This model proposes a decay constant (α) and sedimentation coefficient (s). The model can also be used to calculate the instantaneous sedimentation rate of the clay suspensions at any time and any depth for the settling cylinder. These sedimentary characteristics were simulated by adopting the established deposition model. The results show that the model is capable of predicting the time required for the complete sedimentation of particles in the aqueous system, suggesting the feasibility of engineering wastewater treatment, site dredging, etc.

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46

Munir, Badrul y Kim Kyoo Ho. "Band Gap Optimization by Ga and S Additions in CuInSe₂ for Solar Cell Absorber Applications". Applied Mechanics and Materials 110-116 (octubre de 2011): 1176–80. http://dx.doi.org/10.4028/www.scientific.net/amm.110-116.1176.

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Gallium or sulphur additions in CuInSe2 were prepared using RF magnetron sputtering and pulsed laser deposition respectively. All of the observed thin films show a chalcopyrite structure with the S addition increases the favourable (112) peak. The optical absorption coefficients were slightly decreased. The films energy band gap could be shifted from 1.04 to 1.68eV by adjusting the mole ratio of S/(S+Se) and In/(In+Ga). It is possible to obtain the optimum energy band gap by adding S solute or Ga at a certain ratio in favour of Se and In respectively. It is also necessary to control the ratio of Ga and S additions and to retain a certain portion of In to provide better properties of CIS films.

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47

Mhatre, Sameer, Anna Zigelman, Ludmila Abezgauz y Ofer Manor. "Influence of a Propagating Megahertz Surface Acoustic Wave on the Pattern Deposition of Solute Mass off an Evaporating Solution". Langmuir 32, n.º 37 (6 de septiembre de 2016): 9611–18. http://dx.doi.org/10.1021/acs.langmuir.6b01341.

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48

Zhan, Xiaohong, Junjie Zhou, Chaoqi Qi y Dongdong Gu. "The influence of heat input on the microstructure and solute segregation mechanism of invar alloy laser melting deposition process". Materials Research Express 5, n.º 11 (14 de septiembre de 2018): 116530. http://dx.doi.org/10.1088/2053-1591/aaded2.

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49

Chen, J. P., A. Hazra y Z. Levin. "Parameterizing ice nucleation rates using contact angle and activation energy derived from laboratory data". Atmospheric Chemistry and Physics 8, n.º 24 (15 de diciembre de 2008): 7431–49. http://dx.doi.org/10.5194/acp-8-7431-2008.

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Abstract. The rate of ice nucleation in clouds is not easily determined and large discrepancies exist between model predictions and actual ice crystal concentration measured in clouds. In an effort to improve the parameterization of ice nucleating in cloud models, we investigate the rate of heterogeneous ice nucleation under specific ambient conditions by knowing the sizes as well as two thermodynamic parameters of the ice nuclei – contact angle and activation energy. Laboratory data of freezing and deposition nucleation modes were analyzed to derive inversely the two thermodynamic parameters for a variety of ice nuclei, including mineral dusts, bacteria, pollens, and soot particles. The analysis considered the Zeldovich factor for the adjustment of ice germ formation, as well as the solute and curvature effects on surface tension; the latter effects have strong influence on the contact angle. Contact angle turns out to be a more important factor than the activation energy in discriminating the nucleation capabilities of various ice nuclei species. By extracting these thermodynamic parameters, laboratory results can be converted into a formulation that follows classical nucleation theory, which then has the flexibility of incorporating factors such as the solute effect and curvature effect that were not considered in the experiments. Due to various uncertainties, contact angle and activation energy derived in this study should be regarded as "apparent" thermodynamics parameters.

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50

Tsizh, B. y Z. Dziamski. "Chemical deposition and mechanical application of semiconductors thin films". Scientific Messenger of LNU of Veterinary Medicine and Biotechnologies 23, n.º 95 (9 de abril de 2021): 3–6. http://dx.doi.org/10.32718/nvlvet-f9501.

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Features and main technological methods of forming thin layers of semiconductor materials by methods of chemical deposition and mechanical application are analyzed. The disadvantages of thermal sputtering and cathodic sputtering of thin films in vacuum for multicomponent semiconductor compounds are indicated. Features of chemical deposition of semiconductor films from the gas (steam) phase are presented. Such deposition involves the transfer of source material from the evaporator zone with higher temperature in the form of volatile compounds to the colder surface of the substrate, where the film growth occurs as a result of reaction of transported compounds or their decomposition. It is shown that the growth of the film during chemical vapor deposition is a process of layer-by-layer condensation of atoms or molecules, with the advantageous difference that during chemical deposition the latter are formed as a result of a heterogeneous chemical reaction when there is no need for average free path length of the gas molecules to be larger than the size of the deposition chamber, i.e. no need for critical degree of vacuum. Chemical deposition of thin films from solution is characterized as a process of precipitation of solute which occurs due to the fact that the ionic product exceeds the product of solubility, i.e. it is greater than the constant value characteristic of a saturated solution in the equilibrium state. We emphasize, that chemical deposition from an water solution allows to obtain homogeneous in thickness and structure fine-grained non-textured mechanically stable polycrystalline films with good adhesion to substrates and the required set of properties. The method of pulverization with subsequent pyrolysis is described. This is deposition from intracomplex organometallic compounds, which is based on thermally stimulated reactions between clusters of atoms, chemically active substances of liquid or vapor phase. The method of electrolytic deposition on electrically conductive substrates is characterized. The method is using appropriate salt solutions by co-deposition of individual components, or by deposition on the cathode of one of the components with its subsequent interaction with others present in the solution. We also describe the method of obtaining epitaxial thin films of semiconductor deposition materials. We note that the analyzed methods or their modifications are necessary tool today to create thin-film semiconductor structures with predetermined properties. In the same time, in each particular case the features of each method of obtaining thin semiconductor films should be comprehensively evaluated and, depending on the chemical composition, structure, topology and complex of expected properties, the most effective method should be applied.

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