bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Simple Regression-Based Approach for Prediction of Aqueous Ammonia Vapor Pressure
Authors: Bahadori A. 
Published: August 2012

Abstract
In the process industries, hazardous materials can be released accidentally as vapor, gas or liquid and are dispersed in the atmosphere. Ammonia is one of the most extensively used industrial chemicals. It is highly soluble in water and has toxic and corrosive effects caused by its alkalinity. The evaporation of ammonia may cause extreme cooling when spilled on the skin or eyes; cold burns may result. When inhaled, ammonia dissolves in upper airways and small amounts also in the lower respiratory tract; damage to upper airways is therefore more severe. In this paper, simple predictive tool, which is easier than existing approaches, less complicated with fewer computations and suitable for environmental experts, is presented here for the estimation of aqueous ammonia vapor pressure as a function of ammonia molar fraction in aqueous phase and temperature. The proposed predictive tool works for temperatures in the range of 273 to 373 K. The proposed method is superior owing to its accuracy and clear numerical background, wherein the relevant coefficients can be retuned quickly if more data are available in the future. Estimations are found to be in excellent agreement with the reliable data in the literature with average absolute deviation being around 1.74%. The tool developed in this study can be of immense practical value for the engineers and scientists to have a quick check on the vapor pressure of aqueous ammonia solution at various conditions without opting for any experimental measurements. In particular, chemical engineers and environmental scientists would find the approach to be user-friendly with transparent calculations involving no complex expressions.
Enhanced Productivity Approach using Improved Quality Data
Authors: Izuorgu N 
Published: August 2012

Abstract
In recent times, the cost of identifying and discovering hydrocarbons has increased geometrically from land to the more challenging deepwater environment. The objective for any investor is to reduce this cost and at the same time increase production and reserves. One of the factors in ensuring this objective is met is making the right decisions, which can be achieved with acquisition of the right information and data. Operators base their decisions on both geologic and engineering information, which involves uncertainty. There is one thing today's E&P operators can be certain about: There will be a large element of uncertainty in their decisions as a result of erroneous, missing, or conflicting data that lead to indecision, delays, rework, cost overruns, and increased risk. An important means of quantifying prospect uncertainty is to create realistic geologic and structural models through 3D modeling, which is influenced by data quality and the amount of data at hand. How can this be done without quality data? Quality, reliable data is a crucial component of these decisions, which have a major impact on the asset team's overall goals. Getting the structural model wrong, of course, will impact reserves calculations, production predictions, well placement, and field development planning.
For E&P companies to succeed in deepwater exploration and development, the quality of the data being used for analysis and decisions needs to improve vividly, and data quality processes need to be part of a lifestyle change. E&P data environments are dynamic and complex, made up of multiple interrelated corporate, regional, project, and domain data sources. Data are extracted, manipulated, and processed by various teams and domain groups, and people find themselves wondering how data quality can be maintained in such a dynamic and complex environment. Often organizations attempting to address data quality problems think that an all-or-nothing approach is the answer. Many have conducted massive efforts that involve stopping work to "clean" the data—only to see the data quality degrade once standard workflows are resumed. This "boom and bust" business approach does not work.
This paper focuses on a different approach, which combines methodology and technology that create value by maintaining high-quality data, thus enabling organizations to have the right quality of data to make the right decisions at the right time, thereby reducing uncertainties.
The Effects of Soil Carbon on Phosphorus and Sediment Loss from Soil Trays by Overland Flow
Authors: McDowell R. W. , Sharpley A. N. 
Published: August 2012

ABSTRACTSoil chemical constituents influence soil structure and erosion potential. We investigated manure and inorganic fertilizer applications on soil chemistry (carbon [C] quality and exchangeable cations), aggregation, and phosphorus (P) loss in overland flow. Surface samples (0–5 cm) of a Hagerstown (fine, mixed, semiactive, mesic Typic Hapludalf) soil, to which either dairy or poultry manure or triple superphosphate had been applied (0–200 kg P ha−1 yr−1 for 5 yr), were packed in boxes (1 m long, 0.15 m wide, and 0.10 m deep) to field bulk density (1.2 g cm−3). Rainfall was applied (65 mm h−1), overland flow collected, and sediment and P loss determined. All amendments increased Mehlich 3–extractable P (19–177 mg kg−1) and exchangeable Ca (4.2–11.5 cmol kg−1) compared with untreated soil. For all treatments, sediment transport was inversely related to the degree of soil aggregation (determined as ratio of dispersed and undispersed clay; r = 0.51), exchangeable Ca (r = 0.59), and hydrolyzable carbohydrate (r = 0.62). The loss of particulate P and total P in overland flow from soil treated with up to 50 kg P ha−1 dairy manure (9.9 mg particulate phosphorus [PP], 15.1 mg total phosphorus [TP]) was lower than untreated soil (13.3 mg PP, 18.1 mg TP), due to increased aggregation and decreased surface soil slaking attributed to added C in manure. Manure application at low rates (<50 kg P ha−1) imparts physical benefits to surface soil, which decrease P loss potential. However, at greater application rates, P transport is appreciably greater (26.9 mg PP, 29.5 mg TP) than from untreated soil (13.3 mg PP, 18.1 mg TP).
Visualizing Bromide and Iodide Water Tracer in Soil Profiles by Spray Methods
Authors: Lu Jianhang , Wu Laosheng 
Published: August 2012

ABSTRACTIn this study we developed and tested a spray method to visualize bromide water tracer in soil profiles. The method is based on the transformation reaction of a white precipitate into a colored one (Prussian blue) in the presence of Br− After application of water containing bromide (0.2–0.4% wt.), a soil profile is dug out from the irrigated area and sprayed with a Br− indication suspension containing ferric ion and silver ferrocyanide precipitate. About two hours later, the pattern of irrigation water movement in the soil profile appears due to the formation of Prussian blue complex. We describe the method and demonstrate its use in a field experiment to visualize water flow paths. Since this method might be subject to possible interference from Cl−, a newly designed method with iodide ion as a water tracer and its indication solution containing soluble starch and ferric ion is also presented and recommended for use in soils with high chloride background.
Relationship between Water Repellency and Native and Petroleum‐Derived Organic Carbon in Soils
Authors: Roy J. L. , McGill W. B. , Lowen H. A. , Johnson R. L. 
Published: August 2012

ABSTRACTSome soils develop severe and persistent water repellency following contamination with crude oil. This study was conducted to characterize and compare the spatial distribution of soil water repellency and residual oil contamination at 12 such sites. The molarity of ethanol droplet (MED) test was used to assess soil water repellency and the content of dichloromethane‐extractable organics (DEO) was used to quantify residual oil in soil. We found a relatively strong positive correlation between MED and DEO in soil (r2 = 0.74). Both variables tended to decrease abruptly with depth at 11 of the 12 study sites. Dichloromethane‐extractable organics similarly decreased with depth in control adjacent soil (MED = 0 M), but from an average concentration one to two orders of magnitude lower than in water‐repellent soil. Using data from corresponding control adjacent and water‐repellent soils, we determined that approximately 29 and 10% of measured total organic carbon in water‐repellent A‐ and B‐horizon soil, respectively, consists of dichloromethane‐insoluble organic carbon of petroleum origin. We propose that this fraction contains most of the causative agents of soil water repellency at the studied sites.
Phosphorus in Runoff Assessed by Anion Exchange Resin Extraction and an Algal Assay
Authors: Uusitalo Risto , Ekholm Petri 
Published: August 2012

ABSTRACTEutrophication of surface waters can be accelerated by agricultural inputs of phosphorus (P), provided that P is in a form that can be utilized by aquatic algae. We studied anion exchange resin (AER) extraction and a dual culture algal assay (DCAA) for the determination of potentially algal‐available P in water samples without sediment preconcentration. Our material consisted of agricultural and forest runoff and wastewaters. The results obtained by the two methods were essentially equal when the samples contained only small amounts of particulate phosphorus (PP) in relation to dissolved molybdate‐reactive phosphorus (DRP). However, in turbid agricultural runoff, P extracted with AER averaged 72% (n = 17) of the P yield of the 3‐wk DCAA (R2 = 0.94). When the runoff samples were diluted for the AER extraction in the same manner as for the DCAA, the AER‐P yield increased to 85% (n = 5) of DCAA‐P. The minimum detectable value was greater for the AER test (41 μg L−1 AER‐extractable P) than for the DCAA (7 μg L−1 DCAA‐P). At concentrations greater than about 50 μg L−1 AER‐P or DCAA‐P, the accuracy of the methods was satisfactory, with the coefficient of variation in replicated analyses being less than 10% for the AER test and less than 20% for the DCAA. Other anions competing for the exchange sites of the AER decreased P recovery by 15 to 20% when their equivalent concentration exceeded about 4 mmolc L−1, and this effect was relatively constant over a large concentration range. We consider that AER extraction is a suitable low‐cost method to estimate the algal availability of P in runoff samples.
Three Approaches to Define Desired Soil Organic Matter Contents
Authors: Sparling G. , Parfitt R. L. , Hewitt A. E. , Schipper L. A. 
Published: August 2012

ABSTRACTSoil organic C is often suggested as an indicator of soil quality, but desirable targets are rarely specified. We tested three approaches to define maximum and lowest desirable soil C contents for four New Zealand soil orders. Approach 1 used the New Zealand National Soils Database (NSD). The maximum C content was defined as the median value of long‐term pastures, and the lower quartile defined the lowest desirable soil C content. Approach 2 used the CENTURY model to predict maximum C contents of long‐term pasture. Lowest desirable content was defined by the level that still allowed recovery to 80% of the maximum C content over 25 yr. Approach 3 used an expert panel to define desirable C contents based on production and environmental criteria. Median C contents (0–20 cm) for the Recent, Granular, Melanic, and Allophanic orders were 72, 88, 98, 132 Mg ha−1, and similar to contents predicted by the CENTURY model (78, 93, 102, and 134 Mg ha−1, respectively). Lower quartile values (54, 78, 73, and 103 Mg ha−1, respectively) were similar to the lowest desirable C contents calculated by CENTURY (55, 54, 67, and 104 Mg ha−1, respectively). Expert opinion was that C contents could be depleted below these values with tolerable effects on production but less so for the environment. The CENTURY model is our preferred approach for setting soil organic C targets, but the model needs calibrating for other soils and land uses. The statistical and expert opinion approaches are less defensible in setting lower limits for desirable C contents.
Simazine Runoff from Citrus Orchards Affected by Shallow Mechanical Incorporation
Authors: Liu F. , O'Connell N. V. 
Published: August 2012

ABSTRACTSimazine (6‐chloro‐N,N′‐diethyl‐1,3,5‐triazine‐2,4‐diamine) losses via runoff in California are a potential source of environmental contamination because simazine is widely used for weed control during the rainy season from November to March. This study was conducted in two citrus orchards from three rainfall events to evaluate the effects of shallow mechanical incorporation on simazine losses in runoff during the winter. Simazine losses in runoff were compared between row middles that were either undisturbed, the normal orchard practice, or subjected to shallow mechanical incorporation. Mechanical incorporation of row middles significantly reduced runoff volumes by approximately 45 and 28% for the first and second runoff events, respectively. In undisturbed plots, simazine concentrations in runoff from the first runoff event ranged from 0.62 to 0.73 mg L−1; then simazine concentrations rapidly decreased (0.03–0.35 mg L−1) from the second and third runoff events. In disturbed plots, simazine concentrations in runoff from the first runoff event ranged from 0.21 to 0.24 mg−1, but simazine concentrations remained relatively constant between the three runoff events. Total mass recoveries of simazine in runoff ranged from 1.93 to 2.97% and from 0.70 to 0.74% of application from the undisturbed plots and from the disturbed plots, respectively. Low water infiltration rate inhibited surface‐applied herbicide incorporation into the soil matrix with natural rainfall in compacted soils. Mechanical incorporation of row middles significantly reduced runoff volumes, simazine concentrations, and mass losses in runoff after application.
A Biotest for Evaluating Copper Bioavailability to Plants in a Contaminated Soil
Authors: Chaignon V. , Hinsinger P. 
Published: August 2012

ABSTRACTThis work aimed at defining the optimal conditions for a novel ecotoxicological test designed for evaluating the bioavailability and phytotoxicity of metals to plants. This biotest, which provided easy access to roots, shoots, and rhizosphere soil, was applied to a vineyard calcareous soil that had been contaminated by the application of Cu fungicides. A preliminary hydroponic experiment comparing various levels of solution Cu concentration enabled us to determine the no observable adverse effects concentration (NOAEC), which was in the range 5 to 20 μM total Cu (0.01–0.06 μM free Cu ion) for rape (Brassica napus L. cv. Goeland). For the biotest, rape was grown in hydroponic conditions for 21 d in pots designed so that plants developed a planar mat of roots at the surface of a polyamide mesh. By then, the plants were transferred for 4 or 8 d onto a 1‐ or 3‐mm‐thick soil layer that was separated from the root mat by the mesh and connected to a reservoir of nutrient solution or deionized water via a filter paper wick. An 8‐d period was the best option as it enabled plant growth to be significant. The use of 1‐mm soil thickness was recommended if the biotest aimed at investigating root‐induced changes in the rhizosphere. Although it may cause some artifacts, compared with deionized water, nutrient solution provided better standardized conditions for comparing widely differing soil samples. The studied soil did not induce any Cu phytotoxicity in spite of its fairly large total Cu content.
Nitrate Exported in Drainage Waters of Two Sprinkler‐Irrigated Watersheds
Authors: Cavero J. , Beltrán A. , Aragüés R. 
Published: August 2012

ABSTRACTNitrate contamination of surface waters has been linked to irrigated agriculture across the world. We determined the NO3–N loads in the drainage waters of two sprinkler‐irrigated watersheds located in the Ebro River basin (Spain) and their relationship to irrigation and N management. Crop water requirements, irrigation, N fertilization, and the volume and NO3–N concentration of drainage waters were measured or estimated during two‐year (Watershed A; 494 irrigated ha) and one‐year (Watershed B; 470 irrigated ha) study periods. Maize (Zea mays L.) and alfalfa (Medicago sativa L.) were grown in 40 to 60% and 15 to 33% of the irrigated areas, respectively. The seasonal irrigation performance index (IPI) ranged from 92 to 100%, indicating high‐quality management of irrigation. However, the IPI varied among fields and overirrigation occurred in 17 to 44% of the area. Soil and maize stalk nitrate contents measured at harvest indicated that N fertilizer rates could be decreased. Drainage flows were 68 mm yr−1 in Watershed A and 194 mm yr−1 in Watershed B. Drainage NO3–N concentrations were independent of drainage flows and similar in the irrigated and nonirrigated periods (average: 23–29 mg L−1). Drainage flows determined the exported mass of NO3–N, which varied from 18 (Watershed A) to 49 (Watershed B) kg ha−1 yr−1, representing 8 (Watershed A) and 22% (Watershed B) of the applied fertilizer plus manure N. High‐quality irrigation management coupled to the split application of N through the sprinkler systems allowed a reasonable compromise between profitability and reduced N pollution in irrigation return flows.
Significance of Anion Exchange in Pentachlorophenol Sorption by Variable‐Charge Soils
Authors: Hyun Seunghun , Lee Linda S. , Rao P. Suresh C. 
Published: August 2012

ABSTRACTSorption data and subsequent predictive models for evaluating acidic pesticide behavior on variable‐charge soils are needed to improve pesticide management and environmental stewardship. Previous work demonstrated that sorption of pentachlorophenol (PCP), a model organic acid, was adequately modeled by accounting for pH‐ and pKa–dependent chemical speciation and using two organic carbon–normalized sorption coefficients; one each for the neutral and anionic species. Such models do not account for organic anion interaction to positively charged surface sites, which can be significant for variable‐charge minerals present in weathered soils typical of tropical and subtropical regions. The role of anion exchange in sorption of ionizable chemicals by variable‐charge soils was assessed by measuring sorption of PCP by several variable‐charge soils from aqueous solutions of CaCl2, CaSO4, Ca(H2PO4)2 as a function of pH. Differences in sorption from phosphate and chloride electrolyte solutions were attributed to pentachlorophenolate interactions with anion exchange sites. Suppression of PCP sorption by phosphate ranged from negligible in a soil with essentially no positively charge sites, as measured by negligible anion exchange capacity, to as much as 69% for variable‐charge soils. Pentachlorophenolate exchange correlated well with the ratio of pH‐dependent anion exchange capacity to net surface charge. Sorption reversibility of PCP by both CaCl2 and Ca(H2PO4)2 solutions was also demonstrated. Results for PCP clearly demonstrate that sorption to anion exchange sites in variable‐charge soils should be considered in assessing pesticide mobility and that phosphate fertilizer application may increase the mobility of acidic pesticides.
Polycyclic Aromatic Hydrocarbons in Mountain Soils of the Subtropical Atlantic
Authors: Ribes A. , Grimalt J. O. , García C. J. Torres , Cuevas E. 
Published: August 2012

ABSTRACTSurface soil samples from various altitudes on Tenerife Island, ranging from sea level up to 3400 m above mean sea level, were analyzed to study the distribution of 26 polycyclic aromatic hydrocarbons (PAHs) in a remote subtropical area. The stable atmospheric conditions in this island define three vertically stratified layers: marine boundary, trade‐wind inversion, and free troposphere. Total PAH concentrations, 1.9 to 6000 μg/kg dry wt., were high when compared with those in tropical areas and in a similar range to those in temperate areas. In the marine boundary layer, fluoranthene (Fla), pyrene (Pyr), benz[a]anthracene (BaA), and chrysene (C + T) were largely dominant. The predominance of Fla over Pyr may reflect photo‐oxidative processes during atmospheric transport, although coal combustion inputs cannot be excluded. The PAHs found in higher concentration in the soils from the inversion layer were benzo[b + j]fluoranthene (BbjF) + benzo[k]fluoranthene (BkF) > benzo[e]pyrene (BeP) ≈ indeno[1,2,3‐cd]pyrene (Ind) > benzo[a]pyrene (BaP) ≅ benzo[ghi]perylene (Bghi) > coronene (Cor) ≅ dibenz[a,h]anthracene (Dib), reflecting that high temperatures and insolation prevent the accumulation of PAHs more volatile than BbjF in significant amounts. These climatic conditions involve a process of standardization that prevents the identification of specific PAH sources such as traffic, forest fires, or industrial inputs. Only soils with high total organic carbon (TOC) (e.g., 10–30%) preserve the more volatile compounds such as phenanthrene (Phe), methylphenanthrenes (MPhe), dimethylphenanthrenes (DMPhe), and retene (Ret). However, no relation between PAHs and soil TOC and black carbon (BC) was found. The specific PAH distributions of the free tropospheric region suggest a direct input from pyrolytic processes related to the volcanic emission of gases in Teide.
An Assessment of Japanese Beetle Defoliation on Aphid‐Resistant and Aphid‐Susceptible Soybean Lines
Authors: Chandrasena Desmi , DiFonzo Christina , Wang Dechun 
Published: August 2012

ABSTRACTAs public institutions and seed companies incorporate soybean aphid (Aphis glycines Matsumura) resistance genes into soybean [Glycine max (L.) Merr.] cultivars, it is important to retain resistance to defoliators. This study compared Japanese beetle (Popillia japonica Newman) defoliation among rag1b and rag3 aphid‐resistant lines (E06901, E06905, and E06906) with a Rag1 aphid‐resistant line (LD05‐16060) and aphid‐susceptible lines (DKB27‐53, SD01‐76R, and Titan RR). Under natural insect pressure, the percentage of leaflets consumed by Japanese beetle was greater on rag1b and rag3 lines (50–86%) than LD05‐16060 (11%) and SD01‐76R (5%). Defoliation on the three most damaged trifoliates was higher on rag1b and rag3 lines (49–54%) and its aphid‐susceptible parent Titan RR (35%) than on LD05‐16060 (5%) and its aphid‐susceptible parent, SD01‐76R (1%). Similarly in laboratory choice and no‐choice tests, greater leaf area was removed from rag1b and rag3 lines. There was more feeding on LD06‐16060 under no‐choice conditions than under choice conditions, suggesting LD05‐16060 was more attractive to Japanese beetle in the absence of a preferred line. At present, the differential susceptibility among these lines cannot be attributed to a specific compound or compounds until sufficient genetic and biochemical studies are conducted. This study shows the importance of monitoring Japanese beetle defoliation in breeding programs to determine the severity of threat posed by this insect on new lines.