836 research outputs found

    Drainmod: A Simulation Model for Shallow Water Table Soils

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    2008 S.C. Water Resources Conference - Addressing Water Challenges Facing the State and Regio

    Forcing number, maximum nullity, and minimum rank theorems concerning the generalized Petersen graph and related observations

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    https://scholarworks.moreheadstate.edu/student_scholarship_posters/1081/thumbnail.jp

    Upward Water Movement in Field Cores

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    Vertical Drainage in Field Cores

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    A statistical approach to optimizing paper spray mass spectrometry parameters

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    Rationale Paper spray mass spectrometry (PS‐MS) was used to analyze and quantify ampicillin, a hydrophilic compound and frequently utilized antibiotic. Hydrophilic molecules are difficult to analyze via PS‐MS due to their strong binding affinity to paper substrates and low ionization efficiency, among other reasons. Methods Solvent and paper parameters were optimized to increase the extraction of ampicillin from the paper substrate. After optimizing these key parameters, a Resolution IV 1/16 fractional factorial design with two center points was employed to screen eight different design parameters simultaneously. Results Pore size, sample volume, and solvent volume were the most significant factors affecting average peak area under the curve (AUC) and the signal‐to‐blank (S/B) ratio for the 1 μg/mL ampicillin calibrant. After optimizing the key parameters, a linear calibration curve with a range of 0.2 μg/mL to 100 μg/mL was generated (R2 = 0.98) and the limit of detection (LOD) and lower limit of quantification (LLOQ) were calculated to be 0.07 μg/mL and 0.25 μg/mL, respectively. Conclusions The statistical optimization procedure undertaken here increased the mass spectral signal intensity by more than a factor of 40. This statistical method of screening followed by optimization experiments proved faster and more efficient, and produced more drastic improvements than typical one‐factor‐at‐a‐time experiments

    Mathematical Surfaces and 3D Printing

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    https://scholarworks.moreheadstate.edu/student_scholarship_posters/1009/thumbnail.jp

    Predicted and Measured Drainable Porosities for Field Soils

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    Experiments were conducted on large field cores to determine the relationship between drainage volume and water table depth for five soils. The measured drainage volumes were less than predicted from the soil water characteristics for three soils, but were in good agreement for the other two. Drainable porosities were calculated from both theoretical and experimental drainage volume-water table depth relationships by assuming that the unsaturated zone is essentially \u27drained to equilibrium, with the water table. The experimental drainable porosities thus obtained were less than predicted. Drainable porosities for drainage in two-dimensions were calculated from experimental results for one-dimension by assuming an elliptical water table profile. These results gave nearly constant drainable porosities for the layered soils and a variable drain-able porosity for Wagram, a homogeneous, sandy soil

    New Mexico pecan production

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    Presented at Urbanization of irrigated land and water transfers: a USCID water management conference on May 28-31, 2008 in Scottsdale, Arizona.Includes bibliographical references.Pecans are a major agricultural crop in New Mexico. Currently there are approximately 11,000 hectares of pecans in the Elephant Butte Irrigation District, consuming more than one third of the annual diversion. The research presented here provides previously unavailable broad-scale estimates of pecan ET and pecan yield response to water. The data at the foundation of this paper were generated using the Regional ET Estimation Model (REEM) developed at New Mexico State University for agricultural and riparian vegetation (Samani et al. 2005, 2006, 2007). REEM uses remotely sensed satellite data to calculate ET as a residual of the energy balance. This research extends the results of REEM to an analysis of yield response to water in irrigated pecan production in the EBID. The study region is rapidly urbanizing and experiencing growing competition for scarce surface and groundwater supplies. The results of this research provide new insight into pecan water use and yields. This research illustrates the linkages that can be made between remote sensing technology, farm-level water management, and yield outcomes. This research sheds new light on the long-standing practice of deficit irrigation in pecans, the yield and conservation impacts of this practice, as well as water conservation policy implications

    Remote sensing techology

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    Presented at Irrigation district sustainability - strategies to meet the challenges: USCID irrigation district specialty conference held on June 3-6, 2009 in Reno, Nevada.Includes bibliographical references.Irrigated agriculture is the largest water user in New Mexico; in southern New Mexico's Lower Rio Grande region, agriculture uses about one million acre-feet of water each year. Previous research has estimated that the average irrigation efficiency in the area is 44%. This relatively low aggregate efficiency indicates a large potential for water savings from agriculture. In order to determine the potential water savings, the amount of water depleted by crop evapotranspiration (ET) in the Mesilla Valley section of the EBID was estimated using satellite information and ground-level measurements to calculate plant consumptive water use on scales ranging from individual farms to the larger watershed. Two areas of potential water savings were evaluated using the satellite-generated consumptive use information: 1) potential water saving at the farm level and 2) potential water saving at the district level. This study found that the majority of farms in the study region were growing crops under deficit irrigation conditions. Therefore, irrigation improvements at the farm-level are likely to increase both yields and water depletion. Potential water savings at the district level were evaluated by comparing the total volume of water diverted for irrigation versus aggregate ET. From the satellite-generated ET data, district-level efficiency was determined to be 55% in 2002 (a full allocation year). Thus, there appears to be a potential for improving district-level efficiency. This can be accomplished by using regional ET depletion values to plan water releases from the reservoir and improve the diversion and distribution within the canal networks
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