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Full-Text Articles in Physical Sciences and Mathematics
Understanding The Mechanisms Of Lead, Copper, And Zinc Retention By Phosphate Rock, R. X. Cao, L. Q. Ma, R. D. Rhue, C. S. Appel
Understanding The Mechanisms Of Lead, Copper, And Zinc Retention By Phosphate Rock, R. X. Cao, L. Q. Ma, R. D. Rhue, C. S. Appel
Earth and Soil Sciences
The solid-liquid interface reaction between phosphate rock (PR) and metals (Pb, Cu, and Zn)was studied. Phosphate rock has the highest affinity for Pb, followed by Cu and Zn, with sorption capacities of 131, 114, and 83.2 mmol kg-1 PR, respectively. In the Pb-Cu-Zn ternary system, competitive metal sorption occurred with sorption capacity reduction of 15.2%, 48.3%, and 75.6% for Pb, Cu, and Zn, respectively. A fractional factorial design showed the interfering effect in the order of Pb>Cu>Zn. Desorption of Cu and Zn was sensitive to pH change, increasing with pH decline, whereas Pb desorption was decreased with a …
Cal Poly's Eswcc Teaches The Next Generation Of Soil Scientists, M. Perry, C. Appel
Cal Poly's Eswcc Teaches The Next Generation Of Soil Scientists, M. Perry, C. Appel
Earth and Soil Sciences
Since 1992, members of Cal Poly San Luis Obispo’s Earth, Soil, and Water Conservation Club (ESWCC), sponsored by the MESA Agricultural Initiative, have volunteered their time and expertise to educate middle-school students in soil science. ESWCC members assemble soil testing kits containing three soils, pH testing materials, and instructions for analyzing soil pore space, water infiltration rates, and soil texture by “feel”. The kits help over 200 California teachers convey the importance of soil science through simple physical and chemical procedures that provide a deeper understanding of soil. ESWCC members train teachers to run classroom experiments and to relate soil …
Point Of Zero Charge Determination In Soils And Minerals Via Traditional Methods And Detection Of Electroacoustic Mobility, Chip Appel, Lena Q. Ma, R. Dean Rhue, Elizabeth Kennelley
Point Of Zero Charge Determination In Soils And Minerals Via Traditional Methods And Detection Of Electroacoustic Mobility, Chip Appel, Lena Q. Ma, R. Dean Rhue, Elizabeth Kennelley
Earth and Soil Sciences
Points of zero charge were determined on two highly weathered surface soils from Puerto Rico, an Oxisol and Ultisol, as well as mineral-standard kaolinite and synthetic goethite using three methods: (1) potentiometric titration measuring the adsorption of H+ and OH− on amphoteric surfaces in solutions of varying ionic strength (I) (point of zero salt effect), (2) direct assessment of surface charges via non-specific ion adsorption as a function of pH and I (point of zero net charge), and (3) electroacoustic mobility of reversible particles as it varies with pH and I (isoelectric point). The first two methods yielded points of …
The Design And Construction Of A Rainfall Simulator, Jacqueline Blanquies, Misty Scharff, Brent Hallock
The Design And Construction Of A Rainfall Simulator, Jacqueline Blanquies, Misty Scharff, Brent Hallock
Earth and Soil Sciences
A reliable, accurate and portable rainfall simulator was needed for vegetative and erosion control research at California Polytechnic State University, San Luis Obispo (Cal Poly) for California Department of Transportation (Caltrans) and California State University Sacramento. This simulator was designed to be easily set up and maintained as well as able to create a variety of rainfall regimes. The nozzle performance tests and lateral spacing tests were performed at Cal Poly’s Erosion Research Facility. This simulator was designed and constructed based upon the principles of the Norton Ladder Type Rainfall Simulator. This simulator is the standard for research involving simulated …
Vegetation Establishment For Erosion Control Under Simulated Rainfall, Brent G. Hallock, Misty Scharff, Steve Rein, Kaila Dettman
Vegetation Establishment For Erosion Control Under Simulated Rainfall, Brent G. Hallock, Misty Scharff, Steve Rein, Kaila Dettman
Earth and Soil Sciences
The California Department of Transportation (Caltrans) manages rights of ways that transect 41 m H (101m ac) and span over 3000 m (9000 ft) in elevation from seashore to sup alpine. There are approximately 4,900 native and 1,000 naturalized alien plant species in California. Only a few hundred are reliably useful in erosion and sediment control. Specifying native and naturalized vegetation mixes for use in hydroseeding or plug planting in conjunction with mechanical erosion control methods can have varying result for minimizing accelerated soil erosion. To investigate these factors, Cal Poly, San Luis Obispo, in conjunction with Caltrans and CSU, …
Selectivities Of Potassium-Calcium And Potassium-Lead Exchange In Two Tropical Soils, Chip Appel, Lena Q. Ma, R. Dean Rhue, William Reve
Selectivities Of Potassium-Calcium And Potassium-Lead Exchange In Two Tropical Soils, Chip Appel, Lena Q. Ma, R. Dean Rhue, William Reve
Earth and Soil Sciences
Measurement of cation selectivity in soils provides important information about the affinity and binding strength of a particular cation on soil surfaces. Gaines-Thomas (KGT) selectivity coefficients were determined for a variety of K/Ca and K/Pb ratios on an Oxisol and Ultisol soil from Puerto Rico. The calculated KGT values indicated a preference for K+ over Ca2+ or Pb2+. The selectivity for Pb2+ was significantly greater than that for Ca2+ due to Pb2+'s larger hydrated charge density relative to that of Ca2+. The patterns of selectivity were independent …