bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative Evaluations of Surface Characteristics of cp Titanium, Ti-6AI-4V and Ti-15Mo-2.8Nb-0.2Si (Timetal® 21SRx)
Authors: Petersen DW , Lemons JE , Lucas LC 
Published: August 2005

Abstract
Commercially pure titanium (cpTi), Ti-6A1-4V (Ti64), and Ti-15Mo-2.8Nb-0.2Si (21SRx), with three unique atomic, alpha, alpha-beta, and beta grain structures, respectively, were subjected to three different surface treatments: cleaning, nitric acid passivation, and heat treatment. Experiments were conducted to determine the effects of the type of material and surface modifications on the substrate microstructure, surface oxide composition and thickness, and resultant corrosion behavior.
Metallography showed the cpTi groups were an equiaxed single alpha phase material, the Ti64 groups a dual-phase alpha-beta material, and the 21SRx groups an equiaxed beta material. The different surface treatments did not alter the substrate microstructures of any groups.
Spectroscopic (AES) results showed typical titanium and titanium alloy spectra with dominant Ti and O peaks for all sample groups, indicative of titanium dioxide. In addition, small Al and Mo peaks were detected throughout the surface oxides of the Ti64 and 21SRx specimens, respectively. AES depth profiling showed no significant difference in the oxide thickness between all the Cleaned and Passivated groups regardless of metal or alloy group. However, all the Heat Treated groups had significantly thicker oxides.
In general, corrosion results showed Passivated and Heat Treated groups to have similar corrosion properties and significantly improved corrosion resistances compared to the Cleaned groups. All impedance spectra fit into the Randles equivalent circuit model, and all sample groups exhibited near ideal capacitive behavior (φ ≅ 90°) expected for titanium and its alloys.
Characteristics of Beryllium Oxide and Beryllium Metal Powders for Use as Reference Materials
Authors: Stefaniak AB , Hoover MD , Day GA , Ekechukwu AA , Whitney GE , Brink CA , Scripsick RC 
Published: August 2005

Abstract
Laboratory evaluations of commercially available powders of beryllium oxide (BeO) and beryllium metal, with special emphasis on type UOX-125 BeO and type I-400 beryllium metal, are ongoing to develop reference materials for evaluating analytical chemistry digestion methods and facilitating occupational health studies. Measured properties of the powders include morphology, size, density, specific surface area (SSA); crystalline and elemental composition, surface chemistry, and in vitro dissolution in hydrochloric acid (HCl) (pH 1), phagolysosomal simulant fluid (PSF) (pH 4.5), and serum ultrafiltrate (pH 7.3). The powders were also used to evaluate the digestion and recovery efficiencies for commonly used U.S. Environmental Protection Agency (EPA), National Institute for Occupational Safety and Health (NIOSH), and Occupational Safety and Health Administration (OSHA) standard analytical methods. UOX-125 BeO powder has high-purity and aggregate cluster morphology with SSA independent of aerodynamic particle cluster size, which results in dissolution kinetics that are independent of cluster size. I-400 beryllium metal powder has high-purity and compact particle morphology with SSA that increases as particle size decreases, which causes size-dependent dissolution kinetics (i.e., smaller particles dissolve more quickly than larger particles). The PSF and HCl chemical dissolution rate constants (g·cm−2·day−1) for the BeO powder were a factor of 10 lower than for the metal powder. Concomitantly, the EPA and NIOSH analytical methods, which used aggressive digestion procedures (e.g., microwave-assisted sample digestion or perchloric acid), gave more complete recovery of beryllium from BeO compared to the OSHA analytical method. Our characterization data suggest that these BeO and metal powders hold promise for use as analytical reference materials. We recommend continued laboratory collaborations to evaluate and apply these BeO and beryllium metal powders as analytical reference materials.
Habitat Use by Juvenile Salmonids in the Smith River Estuary, California
Authors: Quiñones Rebecca M. , Mulligan Timothy J. 
Published: August 2005

AbstractEstuaries are highly productive areas that serve as important nursery habitat for many species of fish. Estuaries provide juvenile salmonids Oncorhynchus spp. with foraging habitats, refuge from predators, and areas in which smoltification and orientation for return migrations can occur. Our primary goal was to describe how juvenile salmonids use the Smith River estuary in northern California, a system that is largely devoid of instream cover and the slough habitat it once contained. The presence of juvenile salmonids was quantified through direct observation (snorkel surveys) and calculations of relative densities in the midchannel and stream margin habitats of the estuary. We completed a total of 755 dives between May 1999 and November 2000. We found that significant differences existed between the relative densities of juvenile Chinook salmon O. tshawytscha and trout (coastal cutthroat trout O. clarkii clarkii and steelhead O. mykiss) observed in habitats with and without cover along stream margins. Stepwise logistic analysis was used to correlate the presence or absence of Chinook salmon and trout to stream reach, habitat type, flow (m3/s), salinity (‰), temperature (°C), and depth (m). In general, juvenile salmonids appeared to preferentially use habitats with overhanging riparian vegetation. However, Chinook salmon presence was most correlated with areas of low salinity (<5‰), while trout presence was most influenced by habitat type. Trout were present most often in stream margin habitats, regardless of other physical factors. Our study demonstrates that riparian vegetation may be an essential component of juvenile salmonid rearing habitat in estuaries with little instream cover.
Temporal Variability in Physical Speciation of Metals during a Winter Rain‐on‐Snow Event
Authors: Morrison Matthew A. , Benoit Gaboury 
Published: August 2005

ABSTRACTParticulate matter in urban rivers transports a significant fraction of pollutants, changes rapidly during storm events, and is difficult to characterize. In this study, the physical speciation of trace metals and organic C in an urban river and upstream headwaters site in Torrington, CT, were measured during a winter rain‐on‐snow event. In addition, a selective fractionation scheme, using membrane and tangential‐flow ultrafiltration methods to separate suspended particulate matter into sand, silt, clay, and colloid fractions, was evaluated based on the appropriateness of the chosen size categories. During peak runoff at the urban river site, total‐recoverable concentrations of the metals Cu and Pb increased 6‐ and 13‐fold to 16.9 and 9.5 μg L−1, respectively, compared with baseflow concentrations. Concentrations of Cu and Pb reached only 0.9 and 0.86 μg L−1 at the headwaters site. For the measured storm event, the majority of metals were transported by the urban river in association with coarse silt (20–80 μm particle diam.) during peak runoff. During peak runoff at the urban site, organic C associated with the large colloid fraction (0.1–1.0 μm) increased from 5% (at baseflow) to 54% of the total C in transport, whereas dissolved organic C and that associated with smaller colloids decreased from 91.5% (at baseflow) to 41% of the total. Other elements that were monitored as part of the study were Na, K, Ca, Mg, Fe, Mn, Al, Cd, Cl−, NO3−, and SO2−4 The chosen fractionation scheme was useful to characterize pollutant transport during this event, but further testing should be undertaken to determine the most appropriate size range categories, and to ensure that the sizes measured are comparable to those used in other studies.
Long‐Term Effects of Sustained Beef Feedlot Manure Application on Soil Nutrients, Corn Silage Yield, and Nutrient Uptake
Authors: Ferguson Richard B. , Nienaber John A. , Eigenberg Roger A. , Woodbury Brian L. 
Published: August 2005

ABSTRACTA field study was initiated in 1992 to investigate the long‐term impacts of beef feedlot manure application (composted and uncomposted) on nutrient accumulation and movement in soil, corn silage yield, and nutrient uptake. Two application strategies were compared: providing the annual crop nitrogen (N) requirement (N‐based rate) or crop phosphorus (P) removal (P‐based rate), as well as a comparison to inorganic fertilizer. Additionally, effects of a winter cover crop were evaluated. Irrigated corn (Zea mays L.) was produced annually from 1993 through 2002. Average silage yield and crop nutrient removal were highest with N‐based manure treatments, intermediate with P‐based manure treatments, and least with inorganic N fertilizer. Use of a winter cover crop resulted in silage yield reductions in four of ten years, most likely due to soil moisture depletion in the spring by the cover crop. However, the cover crop did significantly reduce NO3–N accumulation in the shallow vadose zone, particularly in latter years of the study. The composted manure N‐based treatment resulted in significantly greater soil profile NO3–N concentration and higher soil P concentration near the soil surface. The accounting procedure used to calculate N‐based treatment application rates resulted in acceptable soil profile NO3–N concentrations over the short term. While repeated annual manure application to supply the total crop N requirement may be acceptable for this soil for several years, sustained application over many years carries the risk of unacceptable soil P concentrations.
Amendment Effects on Soil Test Phosphorus
Authors: Brauer D. , Aiken G. E. , Pote D. H. , Livingston S. J. , Norton L. D. , Way T. R. , Edwards J. H. 
Published: August 2005

ABSTRACTApplications of animal manures have increased soil test P values in many parts of the USA and thus increased the risk that soil P will be transferred to surface water and decrease water quality. To continue farming these areas, landowners need tools to reduce the risk of P losses. A field experiment was conducted near Kurten, TX, on a Zulch fine sandy loam (thermic Udertic Paleustalfs) with Bray‐1 P values exceeding 3000 mg P kg−1 soil (dry wt.) in the Ap horizon to evaluate the effectiveness of soil amendments for reducing soil test P values. Soils were amended annually from 1999 to 2001 with 1.5 and 5.0 Mg gypsum ha−1, 1.4 Mg alum ha−1, or 24.4 Mg ha−1 of waste paper product high in Al alone or in combination with 1.5 Mg gypsum ha−1 and/or 1.4 Mg alum ha−1 These treatments supplied a maximum of 225 and 1163 kg ha−1 yr−1 of Al and Ca, respectively. Soil Bray‐1 P and dissolved reactive P levels were monitored from 1999 to 2004. None of the soil amendment treatments affected Bray‐1 P values. Only annual additions of 5.0 Mg gypsum ha−1 from 1999 to 2001 significantly reduced soil dissolved reactive P. Dissolved reactive P levels reached minimal levels after two applications of 5.0 Mg gypsum ha−1 but increased in 2003 and 2004. These results indicate that soil dissolved reactive P levels can be reduced if sufficient amounts of gypsum were added to supply Ca in amounts similar to the soil test P values.
Effects of Commercial Diazinon and Imidacloprid on Microbial Urease Activity in Soil and Sod
Authors: Ingram C. W. , Coyne M. S. , Williams D. W. 
Published: August 2005

ABSTRACTDiazinon [O,O‐diethyl O‐2‐isopropyl‐6‐methyl(pyrimidine‐4‐yl) phosphorothioate] and imidacloprid [1‐(1‐[6‐chloro‐3‐pyridinyl]methyl)‐N‐nitro‐2‐imidazolidinimine] are applied to lawns for insect control simultaneously with nitrogenous fertilizers such as urea, but their potential effect on urease activity and nitrogen availability in turfgrass management has not been evaluated. Urease activity in enzyme assays, washed cell assays, and soil slurries was examined as a function of insecticide concentration. Intact cores from field sites were used to assess the effect of insecticide application on urease activity in creeping bentgrass (Agrostis palustris Huds.) and bluegrass (Poa pratensis L.) sod. Bacterial urease from Bacillus pasteurii and plant urease from jack bean [Canavalia ensiformis (L.) DC.] were unaffected by the insecticides. Both insecticides inhibited the growth of Proteus vulgaris, a urease‐producing bacterium, but only diazinon significantly reduced urease activity in washed cells; neither insecticide inhibited urease activity in sonicated cells. Neither diazinon nor imidacloprid inhibited urease activity in Woolper soil (fine, mixed, mesic Typic Argiudoll) slurries, but diazinon slightly inhibited urease activity in Maury soil (fine, mixed, semiactive, mesic Typic Paleudalf) slurries. Imidacloprid had no effect on urease activity in creeping bentgrass or bluegrass sod at up to 10 times the commercial application rate. Diazinon briefly, but significantly, reduced urease activity in bluegrass sod. Co‐application of imidacloprid and urea appears to be benign with respect to urease activity in soil and sod. Diazinon, in contrast, appears to have a significant, short‐term, inhibitory effect on the microbial urease‐producing community, but that effect depends on soil type.
Predicting Inter‐Taxa Differences in Plant Uptake of Cesium‐134/137
Authors: Willey Neil J. , Tang Shirong , Watt Nicholas R. 
Published: August 2005

ABSTRACTFor134/137Cs, and many other soil contaminants, research into transfer to plants has focused on particular crops and phytoremediation candidates, producing uptake data for a small proportion of all plant taxa. Despite the significance of differences in uptake between plant taxa, the capacity of soil‐to‐plant transfer models to predict them is currently confined to those taxa for which data exist, there being no method to predict uptake by other taxa. We used residual maximum likelihood (REML) analysis on data from experiments (including 89 plant taxa from China plus 32 phytoremediation candidates) together with data from the literature, to construct a database of relative134/137Cs concentrations in 273 plant taxa. The REML134/137Cs concentrations in plants are not normally distributed but significantly clustered. Analysis of variance (ANOVA), coded with a recent ordinal phylogeny for flowering plants, showed that plant taxa do not behave independently for134/137Cs concentration because 42 and 15% of inter‐taxa differences are associated with phylogeny above the species and ordinal level, respectively. In general, Eudicots, and especially the Caryophyllales, Asterales, and Brassicales, have high134/137Cs concentrations, while the Fabales and Magnoliids, in particular Poales, have low134/137Cs concentrations. Plants of the stress‐tolerant ruderal (S‐R) growth strategysensuGrime have, in general, high concentrations of Cs, while those of the competitive (C) and generalist (C‐S‐R) strategies have low concentrations, although these effects are less pronounced than those of phylogeny. Plant phylogeny and growth strategy might thus be used to predict a significant portion of inter‐taxa differences in plant uptake of134/137Cs.
Runoff Phosphorus Losses from Surface‐Applied Biosolids
Authors: Elliott H. A. , Brandt R. C. , O'Connor G. A. 
Published: August 2005

ABSTRACTRunoff losses of dissolved and particulate phosphorus (P) may occur when rainfall interacts with manures and biosolids spread on the soil surface. This study compared P levels in runoff losses from soils amended with several P sources, including 10 different biosolids and dairy manure (untreated and treated with Fe or Al salts). Simulated rainfall (71 mm h−1) was applied until 30 min of runoff was collected from soil boxes (100 × 20 × 5 cm) to which the P sources were surfaced applied. Materials were applied to achieve a common plant available nitrogen (PAN) rate of 134 kg PAN ha−1, resulting in total P loading rates from 122 (dairy manure) to 555 (Syracuse N‐Viro biosolids) kg P ha−1 Two biosolids produced via biological phosphorus removal (BPR) wastewater treatment resulted in the highest total dissolved phosphorus (13–21.5 mg TDP L−1) and total phosphorus (18–27.5 mg TP L−1) concentrations in runoff, followed by untreated dairy manure that had statistically (p = 0.05) higher TDP (8.5 mg L−1) and TP (10.9 mg L−1) than seven of the eight other biosolids. The TDP and TP in runoff from six biosolids did not differ significantly from unamended control (0.03 mg TDP L−1; 0.95 mg TP L−1). Highest runoff TDP was associated with P sources low in Al and Fe. Amending dairy manure with Al and Fe salts at 1:1 metal‐to‐P molar ratio reduced runoff TP to control levels. Runoff TDP and TP were not positively correlated to TP application rate unless modified by a weighting factor reflecting the relative solubility of the P source. This suggests site assessment indices should account for the differential solubility of the applied P source to accurately predict the risk of P loss from the wide variety of biosolids materials routinely land applied.
Simulation of Phytoremediation of a TNT‐Contaminated Soil Using the CTSPAC Model
Authors: Ouyang Y. , Shinde D. , Ma L. Q. 
Published: August 2005

ABSTRACTKnowledge of water movement in the plant‐xylem system and contaminant bioavailability in the soil environment is crucial to evaluate the success of phytoremediation practices. This study investigated the removal of 2,4,6‐trinitrotoluene (TNT) from a contaminated sandy soil by a single poplar (Populus fastigiata) tree through the examinations of temporal variations of xylem water potential, root water uptake, and soil TNT bioavailability. A mathematical model, CTSPAC (Coupled Transport of water, heat, and solutes in the Soil–Plant–Atmosphere Continuum), was modified for the purpose of this study. The model was calibrated using laboratory measurements before its application. Our simulations show that the xylem water potential was high in the roots and low in the leaves with a potential head difference of 3.55 cm H2O, which created a driving force for water flow and chemical transport upward from the roots through the stem to the leaves. The daily average root water uptake rate was 25 cm3 h−1 when an equilibrium condition was reached after 24 h. Our simulations further reveal that no TNT was found in the stem and leaves and only about 1% of total TNT mass was observed in the roots due to the rapid biodegradation and transformation of TNT into its daughter products. About 13% of the soil TNT was removed by the poplar tree, resulting mainly from root uptake since TNT is a recalcitrant compound. In general, the soil TNT bioavailability decreased with time due to the depletion of soil solution TNT by the poplar tree. A constant bioavailability (i.e., 3.1 × 10−6) was obtained in 14 d in which the soil TNT concentration was about 10 mg L−1 Our study suggests that CTSPAC is a useful model to simulate phytoremediation of TNT‐contaminated sites.
Reduction of Copper(II) by Iron(II)
Authors: Matocha C. J. , Karathanasis A. D. , Rakshit S. , Wagner K. M. 
Published: August 2005

ABSTRACTLaboratory and field investigations have clearly demonstrated the important role of reduced iron (Fe(II)) in reductive transformations of first‐row transition metal species. However, interactions of Fe(II) and copper (Cu) are not clearly understood. This study examined the reduction of Cu(II) by Fe(II) in stirred‐batch experiments at pH 5.2 and 5.5 as influenced by chloride (Cl−) concentration (0.002–0.1 M), initial metal concentration (0.1–9.1 mM), and reaction time (1–60 min) under anoxic conditions. Reduction of Cu(II) to Cu(I) by dissolved Fe(II) was rapid under all experimental conditions and the stability of the products explains the driving force for the redox reaction. Under conditions of low [Cl−] and high initial metal concentration, >40% of total Cu and Fe were removed from solution after 1 min, which accompanied formation of a brownish‐red precipitate. X‐ray diffraction (XRD) patterns of the precipitates revealed the presence of cuprite (Cu2O), a Cu(I) mineral, based on d‐spacings located at 0.248, 0.215, 0.151, and 0.129 nm. Fourier transform infrared (FTIR) spectroscopy corroborated XRD data for the presence of Cu2O, with features located at 518, 625, and 698 cm−1 Increasing [Cl−] stabilized the dissolved Cu(I) product against Cu2O precipitation and resulted in more Fe precipitated from solution (relative to Cu) that appears to be present as poorly crystalline lepidocrocite (γ‐FeOOH). This process may be important in anoxic soil environments, where dissolved Fe(II) levels can accumulate.
Broiler Litter as a Micronutrient Source for Cotton
Authors: Tewolde H. , Sistani K. R. , Rowe D. E. 
Published: August 2005

ABSTRACTAnalytically, poultry litter contains nearly all essential micronutrients but the extent of phytoavailability of these nutrients and whether cotton (Gossypium hirsutum L.) and other crop plants can receive adequate amounts of these nutrients from litter is not fully known. The objective of this research was to determine whether cotton receives sufficient amounts of Fe, Cu, Mn, and Zn from litter and estimate the efficiency of cotton in extracting these metal nutrients from litter in the absence of any other source of the micronutrients. The greenhouse research used plastic pots filled with approximately 11 kg of a 2:1 (v/v) sand to vermiculite growing mix. Cotton (cv. Stoneville 474) was grown in the pots fertilized with broiler litter at rates of 30, 60, 90, or 120 g pot−1 in a factorial combination with four supplemental nutrient solution (NS) treatments. The nutrient solutions consisted of full Hoagland's nutrient solution (NS‐full); a solution of the macronutrients N, P, K, Ca, and Mg (NS‐macro); a solution of the micronutrients Fe, Zn, Mn, Cu, B, and Mo (NS‐micro); and water (NS‐none). Based on tissue nutrient analysis, a one‐time broiler litter application supplied adequate amounts of Fe, Cu, and Mn to bring the concentration of these nutrients in upper leaves within published sufficiency ranges. Zinc, with <17 mg kg−1 concentration in the upper leaves, was the only micronutrient below the established sufficiency range regardless of the rate of applied litter. Cotton extracted Fe and Mn more efficiently than Cu or Zn, removing as much as 8.8% of Fe and 7.2% of Mn supplied by 30 g litter pot−1 In contrast, the extraction efficiency was 1.7% for Cu and 1.9% for Zn. Roots accumulated 58% of the total absorbed Fe and 64% of Cu, and leaves accumulated 32% of the Fe and only 13% of the Cu supplied by litter. In contrast, only 16% of the total absorbed Mn and 23% of Zn accumulated in roots while leaves accumulated 64% of the total Mn and 37% of Zn. These results demonstrate that broiler litter is a valuable source of the metal nutrients supplying Fe, Cu, and Mn in full and Zn in part, but a very large fraction of the litter‐supplied metal nutrients remained in the growing mix.
Process engineering research in China: A multiscale, market‐driven approach
Authors: Ng Ka M. , Li Jinghai , Kwauk Mooson 
Published: August 2005

AbstractThe rapidly evolving Chinese process engineering community and its research are described. A multiscale, market‐driven approach is proposed for its future development. In addition to the science and technology, process engineering is broadened to consider the product, sustainability, business and, most importantly, people issues involved. © 2005 American Institute of Chemical Engineers AIChE J, 2005