Sample records for phosphorus 33

  1. Synthesis and characterization of the phosphorus triazides OP(N3)3 and SP(N3)3.

    PubMed

    Zeng, Xiaoqing; Bernhardt, Eduard; Beckers, Helmut; Willner, Helge

    2011-11-01

    Two explosive triazides of phosphorus(V), OP(N(3))(3) and SP(N(3))(3), have been prepared as neat substances and structurally characterized. Both compounds can be handled in gas, liquid, and solid states in submillimolar quantities. The melting points of OP(N(3))(3) and SP(N(3))(3) are +22 and -30 °C, respectively. The two triazides have been characterized by IR (Ar matrix and gas phase) and Raman (solid) spectroscopies. Their single-crystal structures were obtained by X-ray diffraction and found to be significantly distorted from the predicted ideal C(3) symmetry because of intermolecular interactions. The spectroscopic and structural properties are discussed in combination with density functional theory calculations. PMID:21958336

  2. Parameterization of DFTB3/3OB for Sulfur and Phosphorus for Chemical and Biological Applications

    PubMed Central

    2015-01-01

    We report the parametrization of the approximate density functional tight binding method, DFTB3, for sulfur and phosphorus. The parametrization is done in a framework consistent with our previous 3OB set established for O, N, C, and H, thus the resulting parameters can be used to describe a broad set of organic and biologically relevant molecules. The 3d orbitals are included in the parametrization, and the electronic parameters are chosen to minimize errors in the atomization energies. The parameters are tested using a fairly diverse set of molecules of biological relevance, focusing on the geometries, reaction energies, proton affinities, and hydrogen bonding interactions of these molecules; vibrational frequencies are also examined, although less systematically. The results of DFTB3/3OB are compared to those from DFT (B3LYP and PBE), ab initio (MP2, G3B3), and several popular semiempirical methods (PM6 and PDDG), as well as predictions of DFTB3 with the older parametrization (the MIO set). In general, DFTB3/3OB is a major improvement over the previous parametrization (DFTB3/MIO), and for the majority cases tested here, it also outperforms PM6 and PDDG, especially for structural properties, vibrational frequencies, hydrogen bonding interactions, and proton affinities. For reaction energies, DFTB3/3OB exhibits major improvement over DFTB3/MIO, due mainly to significant reduction of errors in atomization energies; compared to PM6 and PDDG, DFTB3/3OB also generally performs better, although the magnitude of improvement is more modest. Compared to high-level calculations, DFTB3/3OB is most successful at predicting geometries; larger errors are found in the energies, although the results can be greatly improved by computing single point energies at a high level with DFTB3 geometries. There are several remaining issues with the DFTB3/3OB approach, most notably its difficulty in describing phosphate hydrolysis reactions involving a change in the coordination number of the phosphorus, for which a specific parametrization (3OB/OPhyd) is developed as a temporary solution; this suggests that the current DFTB3 methodology has limited transferability for complex phosphorus chemistry at the level of accuracy required for detailed mechanistic investigations. Therefore, fundamental improvements in the DFTB3 methodology are needed for a reliable method that describes phosphorus chemistry without ad hoc parameters. Nevertheless, DFTB3/3OB is expected to be a competitive QM method in QM/MM calculations for studying phosphorus/sulfur chemistry in condensed phase systems, especially as a low-level method that drives the sampling in a dual-level QM/MM framework. PMID:24803865

  3. Phosphorus-33-labeled nucleotide 5 prime -triphosphates: Applications in DNA analysis

    SciTech Connect

    Buzby, P.R.

    1992-01-01

    Synthesis of ({gamma}-{sup 33}P) adenosine 5{prime}-triphosphate and ({alpha}-{sup 33}P)2{prime}-deoxyadenosine 5{prime}-triphosphate was accomplished in a way similar to the preparation of {sup 32}P-labeled nucleotides. These nucleotides were then used in a variety of molecular biological applications. The techniques of DNA sequencing and nucleic acid hybridization were used to evaluate potential applications for {sup 33}P labeled nucleotides. The {sup 33}P nucleotides were compared with the {sup 32}P and {sup 35}S nucleotide equivalents for the ability to serve as substrates for various enzymes used to label DNA, T4-bacteriophage polynucleotide kinase, E. coli DNA polymerase, and T7 DNA polymerase. The products of there reactions were either separated by polyacrylamide gel electrophoresis (DNA sequencing) or used as hybridization probes on a nylon membrane. The isotopically labeled DNA was detected by autoradiography on X-ray film. The film was evaluated for relative sensitivity of the film versus time for each isotope and the sharpness or resolution of the exposed bands on the film.

  4. Novel Gold(I) and Silver(I) Complexes of Phosphorus-1,1,-dithiolates and Molecular Structure of [O,O’-(Bornyl)2PS2]H3NC(CH3)3

    PubMed Central

    2013-01-01

    Background The novel chiral phosphorus-1,1-dithiolates [4-CH3OC6H4P(S)(OR)S]-[H3NC(CH3)3]+ were synthesized by the reaction of [RPS2)]2 (R?=?4-MeOC6H4) or P2S5 and the respective alcohol ROH (R?=?myrtanyl, 2-naphthylethyl, myrtenyl, borneol) in toluene. The reaction of phosphorus-1,1-dithiolates 1–4 and Au(tht)Cl, AuClPPh3 or AgNO3 and PPh3 gave rise to gold(I)- and silver(I)-complexes in THF. All compounds have been characterised by elemental analyses, IR, NMR (1H-, 13C- and 31P-) spectroscopy as well as MS measurements. Optical rotation values confirmed the chirality of the compounds. The Compound 4 has been characterized structurally by X-ray crystallography. Results Phosphorus-1,1,-dithiolate compounds were formed as liquids and were treated with suitable amine in order to convert them to their salts 1–4 . They have been successfully characterized spectroscopically (IR, 1H, 13C, 31P NMR) as well as mass spectra. The compound 4 has been also structurally by X-ray crystallography. The compound 4 crystallizes in the orthorhombic space group P2(1)2(1)2(1) with Z?=?4. Compounds containing phosphorus and sulfur donor atoms are excellent ligands due to offering many metal complexes especially group 11–12 metals. The synthesis of gold(I) and silver(I) complexes with chiral phosphorus-1,1,-dithiolate and triphenylphosphine have been described and investigated. Conclusions In the present work, we report the synthesis, charactreization of the chiral phosphorus-1,1-dithiolate ligands and preparing the gold(I) and silver(I) phosphorus-1,1-dithiolate or S-donor with phosphine complexes. The molecular structure of the Compound 4 was determined by X-ray diffraction. Due to an easy synthesis method of phosphorus-1,1-dithiolate compounds and a good complexion reagent, it is possible the improvement of the collecting metallic gold or silver from the minerals. When the more ionic salt of phosphorus-1,1-dithiolate compounds were prepared in this way, the water can be used as a cheap solvent. As a result, it can be an alternatively method for the collecting metallic gold or silver from the minerals in future. PMID:23687921

  5. Phosphorus Filter

    USGS Multimedia Gallery

    Tom Kehler, fishery biologist at the U.S. Fish and Wildlife Service's Northeast Fishery Center in Lamar, Pennsylvania, checks the flow rate of water leaving a phosphorus filter column. The USGS has pioneered a new use for acid mine drainage residuals that are currently a disposal challenge, usi...

  6. DESIGN MANUAL: PHOSPHORUS REMOVAL

    EPA Science Inventory

    This manual summarizes process design information for the best developed methods for removing phosphorus from wastewater. his manual discusses several proven phosphorus removal methods, including phosphorus removal obtainable through biological activity as well as chemical precip...

  7. Phosphorus: Riverine system transport

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The transport and transformation of phosphorus (P) in riverine systems fundamentally affects the outcome of watershed mitigation strategies aimed at curbing downstream eutrophication. Phosphorus transport and transformations in streams and rivers are mediated by physical (sediment deposition and res...

  8. Phosphorus poisoning in waterfowl

    USGS Publications Warehouse

    Coburn, D.R.; DeWitt, J.B.; Derby, J.V., Jr.; Ediger, E.

    1950-01-01

    Black ducks and mallards were found to be highly susceptible to phosphorus poisoning. 3 mg. of white phosphorus per kg. of body weight given in a single dose resulted in death of a black duck in 6 hours. Pathologic changes in both acute and chronic poisoning were studied. Data are presented showing that diagnosis can be made accurately by chemical analysis of stored tissues in cases of phosphorus poisoning.

  9. PhosPhorus, Agriculture &

    E-print Network

    Liskiewicz, Maciej

    PhosPhorus, Agriculture & the environment #12;#12;PhosPhorus, Ag riculture & the environment by Gregory Mullins Professor and Extension Specialist, Nutrient Management, Department of Crop and Soil Environmental Sciences, Virginia Tech Reviewed by Wade Thomason, Extension specialist, Crop and Soil

  10. Anthropogenic phosphorus flow analysis of Hefei City, China.

    PubMed

    Li, Sisi; Yuan, Zengwei; Bi, Jun; Wu, Huijun

    2010-11-01

    The substance flow analysis (SFA) method was employed to examine phosphorus flow and its connection to water pollution in the city of Hefei, China, in 2008. As human activity is the driving force of phosphorus flux from the environment to the economy, the study provides a conceptual framework for analyzing an anthropogenic phosphorus cycle that includes four stages: extraction, fabrication and manufacturing, use, and waste management. Estimates of phosphorus flow were based on existing data as well as field research, expert advice, local accounting systems, and literature. The total phosphorus input into Hefei in 2008 reached 7810 tons, mainly as phosphate ore, chemical fertilizer, pesticides, crops and animal products. Approximately 33% of the total phosphorus input left the area, and nearly 20% of that amount was discharged as waste to surface water. Effluent containing excessive fertilizer from farming operations plays an important role in phosphorus overloads onto surface water; the other major emission source is sewage discharge. We also provide suggestions for reducing phosphorus emissions, for example reducing fertilizer use, recycling farming residues, and changing human consumption patterns. PMID:20863550

  11. Phosphorus chemistry on Titan

    NASA Astrophysics Data System (ADS)

    Pasek, Matthew A.; Mousis, Olivier; Lunine, Jonathan I.

    2011-04-01

    Phosphorus is a key element in biology and acts in many critical biochemical functions. The chemistry of phosphorus in the outer Solar System has not yet been quantified, hence the astrobiological relevance of phosphorus to possible life on places like Titan is unconstrained. We evaluate phosphorus chemistry on Titan using a combination of modeling and laboratory techniques. We show that phosphorus chemistry on Titan consists of exogenous phosphates and reduced oxidation state phosphorus compounds, and accretionary phosphine. Accretionary phosphorus is shown to be delivered primarily by rocks and ices in the saturnian sub-nebula, and heating during accretion concentrates phosphine in the crust of Titan. The exogenous compounds are capable of performing biologically-relevant chemistry, however they are active only in environments with substantial liquid water, either pure, or as a mixture with NH 3 or nitrile compounds. In contrast, we show that phosphine is soluble in methane and ethane on Titan's surface, hence phosphine likely participates in the hydrocarbon cycle on Titan. The lack of mobility of phosphate compounds on Titan's surface suggests that if life is present on Titan, it must have a fundamentally different biochemistry than does terrestrial life.

  12. BIOLOGICAL PHOSPHORUS REMOVAL

    EPA Science Inventory

    Three proprietary biological phosphorus removal processes are reviewed. The paper presents the description and development status of these technologies. The paper is a summary of the emerging technology assessment report published by U.S. Environmental Protection Agency in 1984. ...

  13. The problem with phosphorus

    Microsoft Academic Search

    Phillip N. Froelich

    1988-01-01

    Phosphorus is King of the aquatic plant kingdom.1 Without it there would be no growth, no reproduction, and thus no life.2 This simple principle has been concealed from a generation of aquatic scientists seduced by the powers of the Queen Consort, Nitrogen.3If Phosphorus is King and Nitrogen is Queen, then a naive observer4 of the Chess Queen, then a naive

  14. Rethinking early Earth phosphorus geochemistry

    PubMed Central

    Pasek, Matthew A.

    2008-01-01

    Phosphorus is a key biologic element, and a prebiotic pathway leading to its incorporation into biomolecules has been difficult to ascertain. Most potentially prebiotic phosphorylation reactions have relied on orthophosphate as the source of phosphorus. It is suggested here that the geochemistry of phosphorus on the early Earth was instead controlled by reduced oxidation state phosphorus compounds such as phosphite (HPO32?), which are more soluble and reactive than orthophosphates. This reduced oxidation state phosphorus originated from extraterrestrial material that fell during the heavy bombardment period or was produced during impacts, and persisted in the mildly reducing atmosphere. This alternate view of early Earth phosphorus geochemistry provides an unexplored route to the formation of pertinent prebiotic phosphorus compounds, suggests a facile reaction pathway to condensed phosphates, and is consistent with the biochemical usage of reduced oxidation state phosphorus compounds in life today. Possible studies are suggested that may detect reduced oxidation state phosphorus compounds in ancient Archean rocks. PMID:18195373

  15. Phosphorus in prebiotic chemistry

    PubMed Central

    Schwartz, Alan W

    2006-01-01

    The prebiotic synthesis of phosphorus-containing compounds—such as nucleotides and polynucleotides—would require both a geologically plausible source of the element and pathways for its incorporation into chemical systems on the primitive Earth. The mineral apatite, which is the only significant source of phosphate on Earth, has long been thought to be problematical in this respect due to its low solubility and reactivity. However, in the last decade or so, at least two pathways have been demonstrated which would circumvent these perceived problems. In addition, recent results would seem to suggest an additional, extraterrestrial source of reactive phosphorus. It appears that the ‘phosphorus problem’ is no longer the stumbling block which it was once thought to be. PMID:17008215

  16. ENVIRONMENTAL SOIL PHOSPHORUS INDICES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The loss of phosphorus (P) in agricultural runoff and its input to freshwater bodies is known to accelerate eutrophication. As eutrophication of surface water impairs its use for recreation, drinking, and commercial fishing, several strategies have been put in place to minimize impairment by reduci...

  17. Disorders of phosphorus homeostasis

    PubMed Central

    Lee, Richard; Weber, Thomas J.

    2013-01-01

    Purpose of Review The study of phosphorus physiology and investigations into clinical disorders of phosphorus metabolism has blossomed over the past decade. Recent work has confirmed and further extended our knowledge of basic mechanisms of phosphorus metabolism. Recent findings This review will focus on FGF-23 and Klotho, and on the recent further dissection of their roles in phosphorus and skeletal metabolism. Additionally, this review will detail recent studies that implicate a role for these phosphaturic and vitamin D regulating factors in extraskeletal calcification, including that occurring in soft tissue and vascular beds. Summary These findings in total provide fertile ground for investigations into the cause and treatment of abnormal skeletal and extraskeletal calcification in patients with inherited hypophosphatemic disorders. More importantly, and certainly with wider potential clinical application, these studies likewise imply a role for these factors in the pathogenesis of accelerated cardiovascular disease that occurs in patients with the most common hyperphosphatemic disorder, chronic kidney disease. Future studies are needed to confirm a harmful or possibly even beneficial role for FGF-23 and other factors in these disease states, and to determine whether therapeutic manipulation of these factors does truly affect clinical outcomes in patients with hypo- and hyperphosphatemia. PMID:20962635

  18. Soil test phosphorus and cumulative phosphorus budgets in fertilized grassland.

    PubMed

    Messiga, Aimé Jean; Ziadi, Noura; Jouany, Claire; Virkajärvi, Perttu; Suomela, Raija; Sinaj, Sokrat; Bélanger, Gilles; Stroia, Ciprian; Morel, Christian

    2015-03-01

    We analyzed the linearity of relationships between soil test P (STP) and cumulative phosphorus (P) budget using data from six long-term fertilized grassland sites in four countries: France (Ercé and Gramond), Switzerland (Les Verrières), Canada (Lévis), and Finland (Maaninka and Siikajoki). STP was determined according to existing national guidelines. A linear-plateau model was used to determine the presence of deflection points in the relationships. Deflection points with (x, y) coordinates were observed everywhere but Maaninka. Above the deflection point, a significant linear relationship was obtained (0.33 < r (2) < 0.72) at four sites, while below the deflection point, the relationship was not significant, with a negligible rate of STP decrease. The relationship was not linear over the range of STP encountered at most sites, suggesting a need for caution when using the P budget approach to predict STP changes in grasslands, particularly in situations of very low P fertilization. Our study provides insights and description of a tool to improve global P strategies aimed at maintaining STP at levels adequate for grassland production while reducing the risk of P pollution of water. PMID:25681982

  19. Diversity of phosphorus reserves in microorganisms.

    PubMed

    Kulakovskaya, T V; Lichko, L P; Ryazanova, L P

    2014-12-01

    Phosphorus compounds are indispensable components of the Earth's biomass metabolized by all living organisms. Under excess of phosphorus compounds in the environment, microorganisms accumulate reserve phosphorus compounds that are used under phosphorus limitation. These compounds vary in their structure and also perform structural and regulatory functions in microbial cells. The most common phosphorus reserve in microorganism is inorganic polyphosphates, but in some archae and bacteria insoluble magnesium phosphate plays this role. Some yeasts produce phosphomannan as a phosphorus reserve. This review covers also other topics, i.e. accumulation of phosphorus reserves under nutrient limitation, phosphorus reserves in activated sludge, mycorrhiza, and the role of mineral phosphorus compounds in mammals. PMID:25749167

  20. Reduced Phosphorus Compounds in the Environment

    Microsoft Academic Search

    Siyuan C. Morton; Marc Edwards

    2005-01-01

    Reduced phosphorus compounds (phosphorus with oxidation number less than +5) are and often ignored component of the global phosphorus cycle. This paper highlights environments in which reduced phosphorus compounds may be significant, reviews their importance in industrial applications and products, and examines their possible production by anaerobic bacteria or the steel industry. The role of reduced phosphorus in corrosion of

  1. Black phosphorus quantum dots.

    PubMed

    Zhang, Xiao; Xie, Haiming; Liu, Zhengdong; Tan, Chaoliang; Luo, Zhimin; Li, Hai; Lin, Jiadan; Sun, Liqun; Chen, Wei; Xu, Zhichuan; Xie, Linghai; Huang, Wei; Zhang, Hua

    2015-03-16

    As a unique two-dimensional nanomaterial, layered black phosphorus (BP) nanosheets have shown promising applications in electronics. Although mechanical exfoliation was successfully used to prepare BP nanosheets, it is still a challenge to produce novel BP nanostructures in high yield. A facile top-down approach for preparation of black phosphorus quantum dots (BPQDs) in solution is presented. The obtained BPQDs have a lateral size of 4.9±1.6?nm and thickness of 1.9±0.9?nm (ca. 4±2 layers). As a proof-of-concept application, by using BPQDs mixed with polyvinylpyrrolidone as the active layer, a flexible memory device was successfully fabricated that exhibits a nonvolatile rewritable memory effect with a high ON/OFF current ratio and good stability. PMID:25649505

  2. The problem with phosphorus

    NASA Astrophysics Data System (ADS)

    Froelich, Phillip N.

    Phosphorus is King of the aquatic plant kingdom.1 Without it there would be no growth, no reproduction, and thus no life.2 This simple principle has been concealed from a generation of aquatic scientists seduced by the powers of the Queen Consort, Nitrogen.3If Phosphorus is King and Nitrogen is Queen, then a naive observer4 of the Chess Queen, then a naive observer4 of the Chess Game of Life might prematurely conclude, after watching the moves unfolding on the board, that the Queen is all powerful and controls the game. She can move both diagonally and laterally across the board5 and travels long distances in one jump.6 Clones can be created from thin air on the back row.7 She literally dances over the board and controls the tempo of the game.8 A game without a dominant Queen is rare.9

  3. Multiple phosphorus chemical sites in heavily phosphorus-doped diamond

    SciTech Connect

    Okazaki, Hiroyuki [Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530 (Japan); Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency, Okayama 700-8530 (Japan); Yoshida, Rikiya [The Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530 (Japan); Muro, Takayuki; Nakamura, Tetsuya [Japan Synchrotron Radiation Research Institute (JASRI)/SPring-8, 1-1-1 Kouto, Sayo, Hyogo 679-5198 (Japan); Wakita, Takanori; Muraoka, Yuji; Yokoya, Takayoshi [Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530 (Japan); Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency, Okayama 700-8530 (Japan); Research Laboratory for Surface Science, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530 (Japan); Hirai, Masaaki [Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530 (Japan); Research Laboratory for Surface Science, Okayama University, 3-1-1 Tsushima-naka, Okayama 700-8530 (Japan); Kato, Hiromitsu; Yamasaki, Satoshi [Energy Technology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Center 2, Tsukuba, Ibaraki 305-8568 (Japan); Takano, Yoshihiko; Ishii, Satoshi [National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Oguchi, Tamio [Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan)

    2011-02-21

    We have performed high-resolution core level photoemission spectroscopy on a heavily phosphorus (P)-doped diamond film in order to elucidate the chemical sites of doped-phosphorus atoms in diamond. P 2p core level study shows two bulk components, providing spectroscopic evidence for multiple chemical sites of doped-phosphorus atoms. This indicates that only a part of doped-phosphorus atoms contribute to the formation of carriers. From a comparison with band calculations, possible origins for the chemical sites are discussed.

  4. Phosphorus and Global Change

    Microsoft Academic Search

    Holm Tiessen; Maria Victoria Ballester; Ignacio Salcedo

    \\u000a Phosphorus (P) is both an agent of global change, with P loads increasing in most global environments due to the loss of mined\\u000a phosphate from agricultural, industrial, and urban environments, and is affected by global change processes such as land degradation\\u000a or the need for P in biofuel production. P plays a fundamental role in food security and, because the

  5. Phosphorus and the Green Scum

    NSDL National Science Digital Library

    This resource explains the relationship between the overabundance of the element phosphorus in the environment and explosive algae growth (called algae blooms or green scum) as well as the progress toward eutrophication. The origins of excess phosphorus are listed as: too much fertilizer, leaves and grass, human and animal waste, and eroded soils. The site contains suggestions for phosphorus control, including soil testing, composting yard debris, and educating the public.

  6. THE PHOSPHORUS INDEX AND PHOSPHORUS NUTRIENT MANAGEMENT IN PENNSYLVANIA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus management is becoming an increasingly important component of farm nutrient management. Attention has been focused on phosphorus as a result of the role it plays in water quality degradation, specifically accelerated eutrophication. Additionally, there has been a national revision of th...

  7. Phosphorus in Soil and Water

    NSDL National Science Digital Library

    Many waterways are considered polluted due, at least in part, to excessive amounts of phosphorus. This topic-in-depth delves into the issues surrounding phosphorus in the environment. First, Larry G. Bundy at the University of Wisconsin - Madison provides a slide show about phosphorus's presence in soils (1). Students can discover the agronomic need for phosphorus, its effects on water quality and management issues. The second web site, created by the University of Florida Cooperative Extension Service, offers a great overview of how wetlands affect the retention, cycling, and release of phosphorus in wetlands (2). Users will find a straightforward diagram of the phosphorus cycle in wetlands. Next, Manitoba Agriculture, Food, and Rural Initiatives present the reasons for careful management of phosphorus in fertilizers, manure, detergents, sewage, and industrial waste (3). The web site effectively summarizes how phosphorus gets into the surface water and negatively influences the environment. Developed by the USGS, the fourth web site addresses the pollution concerns surrounding agricultural landscapes (4). Visitors can learn about the amounts and effects of the erosion of phosphorus, as well as nitrogen and pesticides, on nearby streams and lakes. Next, the Minnesota Environmental Partnership discusses why Minnesota has restricted the use of phosphorus-containing fertilizers on lawns (5). Visitors can discover tips for buying fertilizers and how to deal with the leftovers. The sixth web site describes the USDA's Agricultural Research Service's findings that residue from water-treatment processes may increase soil's capacity to adsorb phosphorus (6). Users can discover how this may help reduce the transport of phosphorus into the watershed, especially in sandy soils. Next, the Australian Government's National Eutrophication Management Program presents its research examining phosphorus erosion, external things that affect its movement, predictive capabilities, and ways to reduce its movement (7). Visitors can learn about the researchers' discoveries that phosphorus can enter waterways through the subsoil. Lastly, the Minnesota Department of Agriculture describes the concept of a watershed and how they influence water quality (8). Users can find out how to reduce the amount of phosphorus entering nearby streams and lakes and how to help their watershed.

  8. Polarographic determination of phosphorus.

    PubMed

    Pardo, R; Barrado, E; Castrillejo, Y; Batanero, P S

    1983-09-01

    A method has been developed for the determination of phosphorus, as phosphate, by means of the catalytic polarographic wave for the reduction of hydrogen peroxide in the presence of Mo(VI). This reduction is combined with the previous formation and extraction of 12-molybdophosphoric acid. Depending on the extractant chosen, ethyl acetate or methyl isobutyl ketone, the determination limit is 2.3 or 3.1 mug l . respectively. The procedure has been applied to certified steel samples with good results. PMID:18963439

  9. Preparation of high purity phosphorus

    DOEpatents

    Rupp, Arthur F. (Oak Ridge, TN); Woo, David V. (Knoxville, TN)

    1981-01-01

    High purity phosphorus and phosphorus compounds are prepared by first reacting H.sub.3 PO.sub.4 with a lead compound such as PbO to form Pb.sub.3 (PO.sub.4).sub.2. The Pb.sub.3 (PO.sub.4).sub.2 is reduced with H.sub.2 at a temperature sufficient to form gaseous phosphorus which can be recovered as a high purity phosphorus product. Phosphorus compounds can be easily prepared by reacting the phosphorus product with gaseous reactants. For example, the phosphorus product is reacted with gaseous Cl.sub.2 to form PCl.sub.5. PCl.sub.5 is reduced to PCl.sub.3 by contacting it in the gaseous phase with solid elemental phosphorus. POCl.sub.3 can be prepared by contacting PCl.sub.5 in the gaseous phase with solid P.sub.2 O.sub.5. The general process is particularly suitable for the preparation of radiophosphorus compounds.

  10. PHOSPHORUS BASICS Larry G. Bundy

    E-print Network

    Balser, Teri C.

    Terminology · Phosphorus (P) = element name and symbol · P2O5 = phosphate (oxide) Amount of P in fertilizers · Adsorption: removal of ionic P (H2PO4 - , HPO4 2- ) from solution by reaction with solid phase of soil;Phosphorus (P) Reactions in Soils · Soluble P additions (fertilizers) react quickly to form slowly soluble

  11. Molecular Structure of Phosphorus pentachloride

    NSDL National Science Digital Library

    2002-10-01

    Phosphorus pentachloride is an extremely hazardous waste and is highly reactive against water. It has been used as a pesticide and as a component in plastics. In addition, phosphorus pentachloride has been employed as a catalyst in organic synthesis to induce rearrangements. Some of the molecule's properties are having trigonal bipyramidal geometry and a hybridization of sp3d.

  12. Mike Daniels Interstate Phosphorus Issues

    E-print Network

    Mike Daniels Interstate Phosphorus Issues: A Perspective from Arkansas #12;A Brief History growers and require NMP as part of contract · In 2001, Oklahoma proposes a Phosphorus water quality Settlement and Consent Decree · No P application in Eucha-Spavinaw basin · Joint P-Index to be developed

  13. Detrital microbial community development and phosphorus dynamics in a stream ecosystem

    SciTech Connect

    Perkins, R.E.; Elwood, J.W.; Sayler, G.S.

    1986-06-01

    Detrital microbial community development and phosphorus dynamics in a lotic system were investigated in non-recirculating laboratory streams contains leaf detritus. Temporal patterns of microbial colonization, as determined by scanning electron microscopy, indicate leaf species dependency and that bacteria were the first colonizers followed by fungi. An extensive glycocalyx layer developed. Phosphorus incorporation rates of both the whole community and intracellular components were determined by time-course measurements of /sup 33/PO/sub 4/ or /sup 32/PO/sub 4/. Phosphorus turnover rates were determined by a sequential double-labeling procedure using /sup 33/PO/sub 4/ and /sup 32/PO/sub 4/, in which the microbiota were labeled with /sup 33/P until in isotopic equilibrium, then /sup 32/P was added. The turnover rate was determined by time-course measurements of the ratio /sup 32/P to /sup 33/P. Snail grazing resulted in an increase in phosphorus metabolism per unit microbial biomass; however, per unit area of leaf surface no increase was observed. Grazing also caused a two-fold reduction in microbial biomass. The results indicate that microbiota associated with decomposing leaves slowly recycle phosphorus, are slowly growing, and have a low metabolic activity. The spiraling length is shortened by microbiota on a short-term basis; however, it may increase on a long-term basis due to hydrological transport of detritus downstream.

  14. The Chemical Evolution of Phosphorus

    NASA Astrophysics Data System (ADS)

    Jacobson, Heather R.; Thanathibodee, Thanawuth; Frebel, Anna; Roederer, Ian U.; Cescutti, Gabriele; Matteucci, Francesca

    2014-12-01

    Phosphorus is one of the few remaining light elements for which little is known about its nucleosynthetic origin and chemical evolution, given the lack of optical absorption lines in the spectra of long-lived FGK-type stars. We have identified a P I doublet in the near-ultraviolet (2135/2136 Å) that is measurable in stars of low metallicity. Using archival Hubble Space Telescope-Space Telescope Imaging Spectrograph spectra, we have measured P abundances in 13 stars spanning -3.3 <= [Fe/H] <= -0.2, and obtained an upper limit for a star with [Fe/H] ~ -3.8. Combined with the only other sample of P abundances in solar-type stars in the literature, which spans a range of -1 <= [Fe/H] <= +0.2, we compare the stellar data to chemical evolution models. Our results support previous indications that massive-star P yields may need to be increased by a factor of a few to match stellar data at all metallicities. Our results also show that hypernovae were important contributors to the P production in the early universe. As P is one of the key building blocks of life, we also discuss the chemical evolution of the important elements to life, C-N-O-P-S, together. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. This work is supported through program AR-13246. Other portions of this work are based on data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile, and the McDonald Observatory of the University of Texas at Austin.

  15. December 2002 Issue #12 2002 PHOSPHORUS MANAGEMENT ON HIGH PHOSPHORUS SOILS

    E-print Network

    Balser, Teri C.

    December 2002 Issue #12 ­ 2002 PHOSPHORUS MANAGEMENT ON HIGH PHOSPHORUS SOILS Angela Ebeling, Keith Kelling, and Larry Bundy 1/ Introduction Soil phosphorus (P) is important for crop production. Phosphorus test phosphorus (STP) is determined when a soil sample (field cores from the top 6 to 7 inches

  16. Machining aspects of nickel-phosphorus coatings

    SciTech Connect

    Dini, J.W.

    1992-07-01

    Nickel-phosphorus coatings with greater than 10% phosphorus have been widely used for diamond turning applications such as fabrication of large optics and other high precision parts. This paper discusses the importance of phosphorus content of the alloy on wear of the diamond tool and provides some speculation on the role of phosphorus on machining characteristics.

  17. 7 Phosphorus Modeling in Soil and Water

    E-print Network

    163 7 Phosphorus Modeling in Soil and Water Assessment Tool (SWAT) Model Indrajeet Chaubey...........................................................................164 7.2 Phosphorus Modeling in SWAT: Soil Phosphorus Interactions..................167 7.2.1 Initialization of Soil Phosphorus Levels......................................... 168 7.2.2 Mineralization

  18. Phosphorus Dynamic in Wetlands

    NASA Astrophysics Data System (ADS)

    Pant, H. K.

    2010-12-01

    The projected greater warming at higher/northern latitudes in the coming decades due to global climatic changes can mineralize substantial amount of the organic matter and supply massive amount of phosphorus (P) to the water column, and cause the collapse of freshwater wetlands. Thus, the rates and duration of organic matter accumulations/decompositions under rising global temperatures are critical determinants of how a freshwater wetland functions as an ecological unit within a landscape. Phosphorus is a limiting nutrient and a primary controller of eutrophication. Once the external P loads are curtailed, internal P regeneration, resulting from decompositions of detritus and soil/sediment organic matter determine the productivity, as well as the water quality of a wetland. Thus, global rise in temperature not only causes hydro-climatic fluctuations but can also change the composition of aquatic/semi-aquatic communities, in turn, could lead to adverse effect on human food chain to collapse of the ecosystem. While P enrichment may lead to immediate algal blooms in wetlands/aquatic systems, decreased in P input from external sources may not be able to stop the blooms for a considerable period of time depending on the P loading from within. The extent of P mineralization under changing conditions, enzymatic hydrolysis, and estimation of different P pools using 31P NMR in sediments and the water columns showed that the stability and bioavailability of P can greatly be influenced by rise in temperature and fluctuations in water level, thus, are crucial in determining the fate of the freshwater wetlands.

  19. Ironing out the phosphorus problem

    Microsoft Academic Search

    Joshua J Zaritsky; Isidro B Salusky

    2010-01-01

    Control of serum phosphorus remains a vexing problem in chronic kidney disease. Although novel dialysis regimens may provide excellent phosphorus control, phosphate binders remain necessary for most dialysis patients. Block et al. present a phase I clinical trial examining the safety and efficacy of SBR759, a novel non-calcium, iron-based phosphate binder. Although the risks of iron accumulation and hypocalcemia must

  20. Calcium phosphate granulation in anaerobic treatment of black water: a new approach to phosphorus recovery.

    PubMed

    Tervahauta, Taina; van der Weijden, Renata D; Flemming, Roberta L; Hernández Leal, Lucía; Zeeman, Grietje; Buisman, Cees J N

    2014-01-01

    Recovery of phosphorus from wastewater as calcium phosphate could diminish the need for mining of scarce phosphate rock resources. This study introduces a novel approach to phosphorus recovery by precipitation of calcium phosphate granules in anaerobic treatment of black water. The granules formed in the Upflow Anaerobic Sludge Blanket (UASB) reactor at lab- and demonstration-scale were analyzed for chemical composition and mineralogy by Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES), Electron microprobe (EMP), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and micro X-ray Diffraction (XRD). The granules had a diameter of 1-2 mm, organic content of 33 wt%, and phosphorus content of 11-13 wt%. Three calcium phosphate phases were identified in the granules: hydroxyapatite, calcium phosphate hydrate and carbonated hydroxyapatite. Without any addition of chemicals, 7 gP/person/year can be recovered with the calcium phosphate granules, representing 2% of the incoming phosphorus in the UASB reactor. As the heavy metal content was lower compared to other phosphorus recovery products, phosphate rock and phosphorus fertilizer, the calcium phosphate granules could be considered as a new phosphorus product. PMID:24183558

  1. Future directions for agricultural phosphorus research

    SciTech Connect

    Sikora, F.J. (ed.)

    1992-03-01

    Future Directions for Agricultural Phosphorus Research is a collection of papers presented at a workshop in Muscle Shoals, Alabama, on July 18 and 19, 1990. The objective of the workshop was to gather representatives of academia, government, and industry to discuss and debate research needs with phosphorus in agriculture, ranging from basic to applied research. The enclosed papers present information on current knowledge in the areas of (1) identifying phosphorus solid phases in soil, (ii) enhanced phosphorus bioavailability through microbial activity, (iii) phosphorus rock quality, (iv) environmental issues regarding phosphorus in agriculture, (v) predicting phosphorus bioavailability in soil, and (vi) fertilizer management effects on phosphorus availability. Within each paper, the authors suggest future research needs in their area. With the discussion of current knowledge and future research needs, this publication was designed to benefit organizations formulating and developing research plans concerning phosphorus in agricultural systems.

  2. [In situ dynamics of phosphorus in the rhizosphere solution and organic acids exudation of two aquatic plants].

    PubMed

    Wang, Zhen-yu; Wen, Sheng-fang; Luo, Xian-xiang; Li, Ai-feng; Xing, Bao-shan; Li, Feng-min

    2009-08-15

    A mini-rhizotron experiment with Alternanthera philoxeroides and Typha latifolia was conducted to measure the spatial and temporal dynamics of phosphorus in the rhizosphere solution. The organic acids in the in situ rhizosphere soil solution were analyzed. A decreasing phosphorus concentration gradient in soil solution toward the root was observed for both A. philoxeroides and T. latifolia. The phosphorus concentration in the rhizosphere soil solution of A. philoxeroides (2.53 mg x L(-1)) was lower than that of T. latifolia (5.43 mg x L(-1)) in the forth sampling day. Compared to T. latifolia, A. philoxeroides released more malic acid (27.33 umol x L(-1)) which was more efficient in phosphorus mobilization. A. philoxeroides was more effective in phosphorus uptake in the rhizosphere than T. latifolia. PMID:19799282

  3. Semiconducting layered blue phosphorus: a computational study.

    PubMed

    Zhu, Zhen; Tománek, David

    2014-05-01

    We investigate a previously unknown phase of phosphorus that shares its layered structure and high stability with the black phosphorus allotrope. We find the in-plane hexagonal structure and bulk layer stacking of this structure, which we call "blue phosphorus," to be related to graphite. Unlike graphite and black phosphorus, blue phosphorus displays a wide fundamental band gap. Still, it should exfoliate easily to form quasi-two-dimensional structures suitable for electronic applications. We study a likely transformation pathway from black to blue phosphorus and discuss possible ways to synthesize the new structure. PMID:24836265

  4. Semiconducting Layered Blue Phosphorus: A Computational Study

    NASA Astrophysics Data System (ADS)

    Zhu, Zhen; Tománek, David

    2014-05-01

    We investigate a previously unknown phase of phosphorus that shares its layered structure and high stability with the black phosphorus allotrope. We find the in-plane hexagonal structure and bulk layer stacking of this structure, which we call "blue phosphorus," to be related to graphite. Unlike graphite and black phosphorus, blue phosphorus displays a wide fundamental band gap. Still, it should exfoliate easily to form quasi-two-dimensional structures suitable for electronic applications. We study a likely transformation pathway from black to blue phosphorus and discuss possible ways to synthesize the new structure.

  5. AGRICULTURE, PHOSPHORUS MANAGEMENT AND WATER QUALITY IN BRAZIL: OPTIONS FOR THE FUTURE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Freshwater eutrophication, a threat to water quality in many parts of the world, is accelerated by increased inputs of phosphorus (P), of which agricultural runoff is a major contributor. During the last decade in Brazil, there has been a 33% increase in the number of livestock, with most in the So...

  6. Effects of a High-Protein Diet on Regulation of Phosphorus Homeostasis

    PubMed Central

    Hoofnagle, Andrew N.; Kratz, Mario; Weigle, David S.; Callahan, Holly S.; Purnell, Jonathan Q.; Horgan, Angela M.; de Boer, Ian H.; Kestenbaum, Bryan R.

    2013-01-01

    Context: High-protein diets, which are popular for weight loss, contain large quantities of phosphorus. Phosphorus excess and consequent changes in phosphorus regulatory hormones are implicated in vascular calcification and cardiovascular disease. Objective: We tested the hypothesis that a moderate increase in dietary phosphorus during a high-protein diet leads to changes in phosphorus-responsive hormones. Design, Participants, and Setting: We conducted a post hoc analysis of a sequential dietary modification trial in 19 healthy volunteers in the general community. Intervention: Participants received 2 weeks of a weight-maintaining, low-protein (15%) diet, followed by 2 weeks of an isocaloric, high-protein (30%) diet, followed by 12 weeks of an ad libitum high-protein (30%) diet. Main Outcome Measures: Using previously collected samples, plasma concentrations of fibroblast growth factor-23 (FGF-23), PTH, 1,25-dihydroxyvitamin D, and 24,25-dihydroxyvitamin D were measured at 8 time points to assess 24-hour variability and in 24-hour pooled samples to delineate changes at the end of each diet period. Results: Mean dietary phosphorus intake during each study period was 1556, 2071, and 1622 mg/d, respectively. Plasma concentrations of FGF-23 and vitamin D metabolites varied in a diurnal pattern; plasma PTH concentrations varied in a bimodal pattern. After changing from a low- to high-protein isocaloric diet, plasma FGF-23 concentrations decreased slightly (mean ?4.48 pg/mL, 95% confidence interval 1.88–7.07). There were no other statistically significant changes in phosphorus regulatory hormones in response to diet modifications. Conclusions: Among healthy people, an approximate 33% increase in dietary phosphorus after institution of a high-protein diet does not cause large changes in measured concentrations of phosphorus regulatory hormones. PMID:23393178

  7. Phosphorus Additive Chemistry and Its Effects on the Phosphorus Volatility of Engine Oils

    Microsoft Academic Search

    T. W. Selby; R. J. Bosch; D. C. Fee

    2005-01-01

    The most widely used and effective anti-wear\\/anti-oxidation additives in engine oil contain phosphorus that can partially volatilize during engine operation. Unfortunately, volatile phosphorus in the exhaust stream degrades the function of the exhaust catalyst in reducing air pollution. Earlier studies in a special volatility bench test using the Phosphorus Emission Index have shown that phosphorus volatility is not related to

  8. Phosphorus Flamethrower: A Demonstration Using Red and White Allotropes of Phosphorus

    ERIC Educational Resources Information Center

    Golden, Melissa L.; Person, Eric C.; Bejar, Miriam; Golden, Donnie R.; Powell, Jonathan M.

    2010-01-01

    A demonstration was created to display the unique behavior of a familiar element, phosphorus, and to make chemistry more accessible to the introductory student. The common allotropes of phosphorus and their reactivity are discussed. In this demonstration, the white allotrope of phosphorus is synthesized from the red phosphorus obtained from a…

  9. Phosphorus Loss (Risk) IndexesPhosphorus Loss (Risk) Indexes in the Southern Regionin the Southern Region

    E-print Network

    Phosphorus Loss (Risk) IndexesPhosphorus Loss (Risk) Indexes in the Southern Regionin the Southern in the US Sharply, et al. 2003. Development of phosphorus indices for nutrient management planning strategies in the United States. J. Soil Water Cons. Daniel et al. 2002. The Phosphorus Index: Background

  10. Phosphorus: From the Stars to Land & Sea

    E-print Network

    Cummins, Christopher C.

    The chemistry of the element phosphorus offers a window into the diverse field of inorganic chemistry. Fundamental investigations into some simple molecules containing phosphorus reveal much about the ramifications of this ...

  11. Economic feasibility study for phosphorus recovery processes.

    PubMed

    Molinos-Senante, María; Hernández-Sancho, Francesc; Sala-Garrido, Ramón; Garrido-Baserba, Manel

    2011-06-01

    Phosphorus recovery from wastewater has become a necessity for sustainable development because phosphorus is a non-renewable essential resource, and its discharge into the environment causes serious negative impacts. There are no economic incentives for the implementation of phosphorus recovery technologies because the selling price of rock phosphate is lower than phosphorus recovered from sewage. The methodologies used to determine the feasibility of such projects are usually focused on internal costs without considering environmental externalities. This article shows a methodology to assess the economic feasibility of wastewater phosphorus recovery projects that takes into account internal and external impacts. The shadow price of phosphorus is estimated using the directional distance function to measure the environmental benefits obtained by preventing the discharge of phosphorus into the environment. The economic feasibility analysis taking into account the environmental benefits shows that the phosphorus recovery is viable not only from sustainable development but also from an economic point of view. PMID:21809783

  12. Can Eutrophication Influence Nitrogen vs. Phosphorus Limitation?

    E-print Network

    Vallino, Joseph J.

    Can Eutrophication Influence Nitrogen vs. Phosphorus Limitation? George Gregory Bates College, originating largely from septic systems and fertilizers, have caused significant eutrophication in freshwater nitrogen and phosphorus grew the highest concentration of phytoplankton, but eutrophic ponds grew a mean

  13. 14 CFR 33.33 - Vibration.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Vibration. 33.33 Section 33.33 Aeronautics...Reciprocating Aircraft Engines § 33.33 Vibration. The engine must be designed...in any of the engine parts because of vibration and without imparting excessive...

  14. 14 CFR 33.33 - Vibration.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Vibration. 33.33 Section 33.33 Aeronautics...Reciprocating Aircraft Engines § 33.33 Vibration. The engine must be designed...in any of the engine parts because of vibration and without imparting excessive...

  15. 14 CFR 33.33 - Vibration.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Vibration. 33.33 Section 33.33 Aeronautics...Reciprocating Aircraft Engines § 33.33 Vibration. The engine must be designed...in any of the engine parts because of vibration and without imparting excessive...

  16. 14 CFR 33.33 - Vibration.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Vibration. 33.33 Section 33.33 Aeronautics...Reciprocating Aircraft Engines § 33.33 Vibration. The engine must be designed...in any of the engine parts because of vibration and without imparting excessive...

  17. Cholestatic presentation of yellow phosphorus poisoning

    PubMed Central

    Lakshmi, C. P.; Goel, Amit; Basu, Debdatta

    2014-01-01

    Yellow phosphorus, a component of certain pesticide pastes and fireworks, is well known to cause hepatotoxicity. Poisoning with yellow phosphorus classically manifests with acute hepatitis leading to acute liver failure which may need liver transplantation. We present a case of yellow phosphorus poisoning in which a patient presented with florid clinical features of cholestasis highlighting the fact that cholestasis can rarely be a presenting feature of yellow phosphorus hepatotoxicity. PMID:24554916

  18. Cholestatic presentation of yellow phosphorus poisoning.

    PubMed

    Lakshmi, C P; Goel, Amit; Basu, Debdatta

    2014-01-01

    Yellow phosphorus, a component of certain pesticide pastes and fireworks, is well known to cause hepatotoxicity. Poisoning with yellow phosphorus classically manifests with acute hepatitis leading to acute liver failure which may need liver transplantation. We present a case of yellow phosphorus poisoning in which a patient presented with florid clinical features of cholestasis highlighting the fact that cholestasis can rarely be a presenting feature of yellow phosphorus hepatotoxicity. PMID:24554916

  19. Effect of chitosan chewing gum on reducing serum phosphorus in hemodialysis patients: a multi-center, randomized, double-blind, placebo-controlled trial

    PubMed Central

    2014-01-01

    Background HS219 (40 mg chitosan-loaded chewing gum) is designed to bind salivary phosphorus as an add-on to available phosphorus binders. We performed a randomized, placebo-controlled, double-blind study to evaluate the efficacy and safety of HS219 in hemodialysis (HD) patients with hyperphosphatemia as an add-on to phosphorus binders. Methods Sixty-eight HD patients who were maintained on calcium carbonate (n?=?33) or sevelamer hydrochloride (n?=?35) were enrolled. The primary end point was a change in serum phosphorus levels. Secondary end points included changes in levels of salivary phosphorus, serum calcium, parathyroid hormone (PTH), and intact fibroblast growth factor (iFGF) 23. Results Sixty-three patients chewed either HS219 (n?=?35) or placebo (n?=?28) for 30 min, three times a day, for 3 weeks. HS219 was well tolerated and safe. However, HS219 was not superior to placebo with additional reduction of serum phosphorus with respect to phosphorus binders at the end of the chewing period. There were no significant effects of HS219 on reduction of salivary phosphorus, serum calcium, iPTH, or iFGF23 levels. Conclusions The chitosan-loaded chewing gum HS219 does not affect serum and salivary phosphorus levels in Japanese HD patients with hyperphosphatemia. Our findings do not support previous findings that 20 mg of chitosan-loaded chewing gum reduces serum and salivary phosphorus levels. Trail registration ClinicalTrials.gov NCT01039428, 24 December, 2009. PMID:24968790

  20. Nutrient Management Module No. 4 Phosphorus Cycling,

    E-print Network

    Lawrence, Rick L.

    Nutrient Management Module No. 4 Phosphorus Cycling, Testing and Fertilizer Recommendations management 4.Be able to make a phosphorus fertilizer recommendation based on a soil test report 5.Recognize the advantages and disadvantages of different phosphorus fertilizers 4 CCACCACCACCACCA 2 NM2 NM2 NM2 NM2 NM

  1. Effects of phosphorus concentration and light intensity on the biomass composition of Arthrospira (Spirulina) platensis.

    PubMed

    Markou, Giorgos; Chatzipavlidis, Iordanis; Georgakakis, Dimitris

    2012-08-01

    This paper presents the effects of various phosphorus concentrations (10, 50, 250 and 500 mg l(-1) K(2)HPO(4)) on the biomass production and composition of Arthrospira (Spirulina) platensis in relation to light intensity (24, 42 and 60 ?E m(-2) s(-1)). The maximum biomass production was 3,592 ± 392 mg l(-1) and this was observed in 250 mg l(-1) K(2)HPO(4) at 60 ?E m(-2) s(-1) light intensity after 32 days of cultivation. A maximum specific growth rate (?(max)) of 0.55 d(-1) was obtained in 500 mg l(-1) K(2)HPO(4) at 60 ?E m(-2) s(-1). The protein, lipid and chlorophyll contents of the biomass varied from 33.59 to 60.57 %, 5.34 to 13.33 % and 0.78 to 2.00 %, respectively. The most significant finding was that phosphorus limitation (10 mg l(-1) K(2)HPO(4)) caused a drastic increase of the carbohydrate content (59.64 %). The effect of phosphorus limitation on the carbohydrate content was independent of the light intensity. The accumulated carbohydrates are proposed to be used as substrate for biofuel generation via one of the appropriate biomass energy conversion technologies. Also, it was observed that phosphorus removal is a function of biomass density, phosphorus concentration and light intensity. PMID:22806192

  2. Simulating soil phosphorus dynamics for a phosphorus loss quantification tool

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pollution of fresh waters by agricultural phosphorus (P) is a water quality concern. Because soils can contribute significantly to P loss in runoff, it is important to assess how management affects soil P status over time, which is often done with models. Our objective was to describe and validate s...

  3. [Simulation of nitrogen and phosphorus loss in Siling Reservoir watershed with AnnAGNPS].

    PubMed

    Bian, Jin-yun; Wang, Fei-er; Yang, Jia; Yu, Jie; Lou, Li-ping; Yu, Dan-ping

    2012-08-01

    By using annual agricultural non-point source model (AnnAGNPS), this study simulated the export loading of nitrogen and phosphorus in Siling Reservoir watershed in Tiaoxi Basin, and integrated with the simulation results, the spatial distribution characteristics of non-point source pollution in the watershed was analyzed. The result showed that the export loading of nitrogen and phosphorus had similar characteristics: in the study area, the export loading of nutrients were higher in southern and western regions and lower in northern and eastern regions. Forest land mainly made up of bamboo was the main export source of nitrogen and phosphorus loading with the contribution above 90% of nutrient load of whole watershed. Three fertilization practices such as no fertilizer (CK), site-specific nutrient management (SSNM) and farmers' fertilizaction practice (FFP) were used in the scenario analysis. The scenario analysis showed that to a certain degree, SSNM could reduce the nitrogen and phosphorus loss. Comparing with FFP, the reduction of SSNM in dissolved nitrogen (DN), particle nitrogen (PN), dissolved phosphorus (DP) and particle phosphorus (PP) was 8.17%, 4.33%, 9.08% and 1.02%, respectively. PMID:23213887

  4. 3, 15871629, 2006 Marine phosphorus

    E-print Network

    Paris-Sud XI, Université de

    that in the10 coastal ocean. The latter is due to increased transfer of soluble P from deep ocean water become an important reactive P sink in deep-sea sediments during periods of ocean anoxia. Slower ocean on the sedimentary burial of phosphorus. An5 expansion of anoxic bottom waters in the deep ocean, as a result

  5. Major Minerals - Calcium, Magnesium, Phosphorus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Calcium, magnesium and phosphorus are essential elements critically important for the function of the musculoskeletal system, including the formation and transduction of energy and the maintenance of healthy bone. The major calcium concern for physically active healthy middle-aged adults is to consu...

  6. Phosphorus removal by fly ash

    Microsoft Academic Search

    A. Ugurlu; B. Salman

    1998-01-01

    The aim of this work was to investigate the possible use of fly ash generated from thermic power stations in the removal of phosphorus contained in aqueous solutions. A series of batch tests were conducted and the influence of temperature, phosphate concentration, and fly ash dosage on phosphate removal were investigated. The effect of adsorption dosage was not significant at

  7. Texas Phosphorus Index TECHNICAL NOTES

    E-print Network

    Mukhtar, Saqib

    inputs can also increase the biological productivity of surface waters by accelerating eutrophication. Eutrophication is the natural aging of lakes or streams brought on by nutrient enrichment. Phosphorus enrichment areas or practices that have the greatest potential to accelerate eutrophication. It can be used

  8. Clinical Disorders of Phosphorus Metabolism

    PubMed Central

    Yu, George C.; Lee, David B. N.

    1987-01-01

    Deranged phosphorus metabolism is commonly encountered in clinical medicine. Disturbances in phosphate intake, excretion and transcellular shift account for the abnormal serum levels. As a result of the essential role played by phosphate in intracellular metabolism, the clinical manifestations of hypophosphatemia and hyperphosphatemia are extensive. An understanding of the pathophysiology of various phosphate disorders is helpful in guiding therapeutic decisions. Images PMID:3321712

  9. GROUNDWATER POLLUTION BY PHOSPHORUS FERTILIZERS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) is a primary nutrient necessary for plant growth. When soil P level is below what is needed for plant needs, P is supplied to the soil by the addition of P fertilizer or organic residuals (i.e., manure). Because of P fertilizer use in the past few decades or application of manure, a g...

  10. MEASUREMENT OF PHOSPHORUS IN WATER

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) is an essential nutrient for growth and development of algae and other aquatic plants. However, P can cause water pollution if sufficient concentration (25 to 100 µg total P L-1, eutrophic condition) is present in water. Eutrophication (nutrient-rich condition) can significantly incre...

  11. Detrital microbial community development and phosphorus dynamics in a stream ecosystem

    SciTech Connect

    Perkins, R.E.

    1985-01-01

    Detrital microbial community development and phosphorus dynamics in a lotic system were investigated in non-recirculating laboratory streams containing leaf detritus. Temporal patterns of microbial colonization, as determined by scanning electron microscopy, indicate leaf species dependency and that bacteria were the first colonizers followed by fungi. An extensive glycocalyx layer developed. Phosphorus incorporation rates of both the whole community and intracellular components were determined by time-course measurements of /sup 33/PO/sub 4/ or /sup 32/PO/sub 4/. Phosphorus turnover rates were determined by a sequential double-labeling procedure using /sup 33/PO/sub 4/ and /sup 32/PO/sub 4/, in which the microbiota were labeled with /sup 33/P until in isotopic equilibrium, then /sup 32/P was added. The turnover rates was determined by time-course measurements of the ratio /sup 32/P to /sup 33/P. The turnover rate for the maple community was 0.319% h/sup -1/ and ranged from 0.379% h/sup -1/ to 0.577% h/sup -1/ for the intracellular components. The turnover rates for the ungrazed and graved oak microbiota were 0.126% h/sup -1/ and 0.131% h/sup -1/. Snail grazing resulted in an increase in phosphorus metabolism per unit microbial biomass; however, per unit area of leaf surface no increase was observed. Grazing also caused a two-fold reduction in microbial biomass. The results of this investigation indicate that microbiota associated with decomposing leaves slowly recycle phosphorus, are slowly growing, and have a low metabolic activity. The spiraling length is shortened by microbiota on a short-term basis; however, it may increase on a long-term basis due to hydrological transport of detritus downstream.

  12. NASA ASRS (Pub. 33) NASA ASRS (Pub. 33)

    E-print Network

    NASA ASRS (Pub. 33) #12;NASA ASRS (Pub. 33) #12;NASA ASRS (Pub. 33) #12;NASA ASRS (Pub. 33) #12;NASA ASRS (Pub. 33) #12;NASA ASRS (Pub. 33) #12;NASA ASRS (Pub. 33) #12;NASA ASRS (Pub. 33) #12;NASA ASRS (Pub. 33) #12;NASA ASRS (Pub. 33) #12;NASA ASRS (Pub. 33) #12;NASA ASRS (Pub. 33) #12;NASA ASRS

  13. Organic phosphorus sequestration in subtropical treatment wetlands.

    PubMed

    Turner, Benjamin L; Newman, Susan; Newman, Jana M

    2006-02-01

    Diffuse phosphorus pollution is commonly remediated by diverting runoff through treatment wetlands to sequester phosphorus into soil layers. Much of the sequestered phosphorus occurs in organic forms, yet our understanding of its chemical nature is limited. We used NaOH-EDTA extraction and solution 31P NMR spectroscopy to speciate organic phosphorus sequestered in a large treatment wetland (STA-1W) in Florida, USA. The wetland was constructed on previously farmed peat and was designed to remove phosphorus from agricultural runoff prior to discharge into the Everglades. Unconsolidated benthic floc that had accumulated during the 9-year operation of the wetland was sampled along transects through two connected cells dominated by cattail (Typha dominigensis Pers.) and an additional cell colonized by submerged aquatic vegetation, including southern water nymph (Najas guadalupensis(Spreng.) Magnus) and coontail (Ceratophyllum demersum L.). Organic phosphorus was a greater proportion of the sequestered phosphorus in the cattail marsh compared to the submerged aquatic vegetation wetland, but occurred almost exclusively as phosphate diesters and their alkaline hydrolysis products. Itwas therefore markedly different from the organic phosphorus in mineral soils, which is dominated typically by inositol phosphates. Phosphate diesters are readily degradable in most soils, raising concern about the long-term fate of organic phosphorus in treatment wetlands. Further studies are now necessaryto assess the stability of the sequestered organic phosphorus in response to biogeochemical and hydrological perturbation. PMID:16509310

  14. Phosphorus nutrition of terrestrial plants

    Microsoft Academic Search

    Philip J. White; John P. Hammond

    Phosphorus (P) is essential for plant growth and fecundity. It is an integral component of genetic, metabolic, structural\\u000a and regulatory molecules, in many of which it cannot be substituted by any other elements. Tissue P concentrations in well\\u000a fertilized plants approximate 0.4–1.5% of the dry matter (Broadley et al. 2004), most of which is present as nucleic acids and nucleotides,

  15. Phosphorus and Water Quality Paradox

    NASA Astrophysics Data System (ADS)

    Pant, H. K.

    2008-12-01

    Paradoxically, phosphorus (P) is one of the major nutrients for higher agricultural production, as well as it causes eutrophication/algal blooms in aquatic and semi-aquatic systems. Phosphorus loadings from agricultural/urban runoffs into lakes and rivers are becoming a global concern for the protection of water quality. Artificial wetlands are considered as a low cost alternative for treating wastewater including removal of P from sources such as agricultural and urban runoffs. However, the selection of the construction site may well determine the effectiveness of these wetlands. Studies show that P transformations in sediments/ soils are crucial for P sequestration in a wetland rather than the amounts of native P. Using 31Phosphorus Nuclear Magnetic Resonance Spectroscopy (31P NMR), previously unreported an active organic P form, phosphoarginine, was identified, and the study indicates that abandonment of P impacted sites may not solve the P loading problem to the water bodies as the organic P compounds would not be as stable as they were thought, thus, can play a detrimental role in eutrophication of water bodies, after all.

  16. Phosphorus Fertilization of Direct Seeded Tomatoes.

    E-print Network

    Hipp, Billy W.

    1970-01-01

    Harllnqlm 0 Rroodearf loo 200 300 4M) Broodcoat 0 Band Harnnqsn Cloy Ohtonee tba~ P war placed from center of row (hrj 8-1 101 July 1970 Phosphorus Fertilization of Direct Seeded Tomatoes %Ob Appllrd (lb/l) !xas A&M University xas... Growth of Tomatoes .......................... 5 Influence of Phosphorus Rate and Placement on Yield of Field Grown Tomatoes ............ .... 6 Influence of Phosphorus Rate and Placement on Nutrient Uptake by Tomatoes .................... 8 Influence...

  17. Phosphorus Cycling Through Space and Time

    NASA Astrophysics Data System (ADS)

    Filippelli, Gabriel

    2014-05-01

    The cycling of phosphorus, a biocritical element in short supply in nature, is an important Earth system process. Variations in the phosphorus cycle have occurred in the past. For example, the rapid uplift of the Himalayan-Tibet Plateau increased chemical weathering, which led to enhanced input of phosphorus to the oceans. This drove the late Miocene "biogenic bloom." On glacial timescales, phosphorus is quite dynamic. In terrestrial systems, phosphorus soil mineralogy alters rapidly in response to early soil development, and ultimately becomes limited to plant availability in many setting. In marine systems, the loss of the substantial continental margin sink for reactive P occurs during glacial sea-level lowstands, effectively concentrating phosphorus in the deep sea. Finally, in the modern, the phosphorus cycle is dominated by human activity and agriculture, which causes unwanted pollution due to high phosphorus loading and itself poses significant concerns about the ultimate future availability of this nutrient to feed an expanding human population. This presentation will cover several critical components of the phosphorus cycle, including terrestrial and marine systems, through the lens of geologic time. This perspective reveals the significant changes that have occurred in the availability of phosphorus through time, and how other biogeochemical systems have responded to these changes. Furthermore, the perspective provides some sobering insights into the mechanisms behind the concentration of marine phosphorus into viable sources of phosphate rock. The rarity of high-quality phosphate rock deposits and the limitation of easily minable reserves are becoming critical, as the human demand for fertilizer phosphorus far outstrips the geologic rate of replacement and few prospects exist for new discoveries of phosphate rock.

  18. Assessing Long Term Impact of Phosphorus Fertilization on Phosphorus Loadings Using AnnAGNPS

    EPA Science Inventory

    High phosphorus (P) loss from agricultural fields has been an environmental concern because of potential water quality problems in streams and lakes. To better understand the process of P loss and evaluate the different phosphorus fertilization rates on phosphorus losses, the US...

  19. Utilization of phosphorus and calcium and minimal maintenance requirement for phosphorus

    E-print Network

    Paris-Sud XI, Université de

    of a marginal phosphorus deficiency associated or not with an excess of calcium in 5 lots of 4 growing sheepUtilization of phosphorus and calcium and minimal maintenance requirement for phosphorus in growing. In experiment 1, two P-deficient diets (1.2 g/kg DM) poor (LPLCa) or rich (LPHCa) in Ca led to lower

  20. Assessing long term impact of phosphorus fertilization on phosphorus loadings using AnnAGNPS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High phosphorus (P) loss from agricultural fields has been an environmental concern because of potential water quality problems in streams and lakes. To better understand the process of P loss and evaluate the different phosphorus fertilization rates on phosphorus losses, the USDA Annualized AGricu...

  1. Use Phosphorus Free Fertilizer Beginning January 1, 2012, Michigan law restricts phosphorus fertilizer applications on lawns.

    E-print Network

    homeowners and commercial applicators must follow the phosphorus application restrictions. Where can I find on lawns. However, there are a couple of exceptions: · Phosphorus applications for agriculture, gardens (composted manure). The application rate is limited to 0.25 pounds of phosphorus per 1,000 square feet

  2. Original article III. Quantitative aspects of phosphorus excretion

    E-print Network

    Paris-Sud XI, Université de

    phosphorus, with saliva being the major source, and is correlated to factors influencing saliva secretion (DM phosphorus (P from saliva, in- testinal cells, and digestive secretions). Relatively high urinary phosphorus

  3. Soil, Water and Forage Testing Laboratory Phosphorus recommendations applicable for

    E-print Network

    Soil, Water and Forage Testing Laboratory Phosphorus recommendations applicable for methods used #12;Soil, Water and Forage Testing Laboratory Phosphorus recommendations applicable for methods used Laboratory Phosphorus recommendations applicable for methods used by laboratory. Mehlich III by ICP only

  4. Sedimentary phosphorus cycling and a phosphorus mass balance for the Green Bay (Lake Michigan) ecosystem

    USGS Publications Warehouse

    Val, Klump J.; Edgington, D.N.; Sager, P.E.; Robertson, D.M.

    1997-01-01

    The tributaries of Green Bay have long been recognized as major sources of phosphorus in the Lake Michigan basin. The status of Green Bay as a sink or source of phosphorus for Lake Michigan proper has been less well defined. The bay receives nearly 70% of its annual load of phosphorus (700 metric tons (t)??year-1) from a single source: the Fox River. Most of this phosphorus is deposited in sediments accumulating at rates that reach 160 mg??cm-2??year-1 with an average of 20 mg??cm-2 year-1. The phosphorus content of these sediments varies from 70 ??mol??g-1. Deposition is highly focused, with ???0% of the total sediment accumulation and at least 80% of the phosphorus burial occurring within 20% of the surface area of the bay. Diagenetic and stoichiometric models of phosphorus cycling imply that >80% of the phosphorus deposited is permanently buried. External phosphorus loading to the bay is combined with sediment fluxes of phophorus to arrive at a simple phosphorus budget. Green Bay acts as an efficient nutrient trap, with the sediments retaining an estimated 70-90% of the external phosphorus inputs before flowing into Lake Michigan.

  5. Early growth and N 2 -fixation of leucaena and gliricidia at different levels of phosphorus application

    Microsoft Academic Search

    N. Sanginga; M. Larkin

    1992-01-01

    The phosphorus (P) uptake and use efficiency in relation to N2 fixation and growth of three provenances of gliricidia (Gliricidia sepium) two cultivars of leucaena (Leucaena leucocephala) and one ofL. diversifolia, all inoculated withRhizobium, were determined at five levels of P application. Increasing the P application rate resulted in a 33% increase in dry matter and total N ofL. diversifolia

  6. Phosphatase Hydrolysis of Soil Organic Phosphorus Fractions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant available inorganic phosphorus (Pi) is usually limited in highly weathered Ultisols. The high Fe, Al, and Mn contents in these soils enhance Pi retention and fixation. The metals are also known to form complexes with organic phosphorus (Po) compounds. Hydrolysis of Po compounds is needed for P...

  7. Adsorption characteristic studies of phosphorus onto laterite

    Microsoft Academic Search

    Liang Zhang; Song Hong; Jing He; Fuxing Gan; Yuh-Shan Ho

    2011-01-01

    Soil has been widely used in many wastewater treatment systems, and proved to be an effective substrate for phosphorus removal and retention. It is significant to study its adsorption characteristics by using appropriate theoretical models. In this study, laterite (or red soil) was selected as an example to investigate the adsorption characteristic of phosphorus onto soil with the Langmuir, Freundlich,

  8. The Pennsylvania Phosphorus Index, Version 2

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increased attention on phosphorus based management due to water quality concerns has prompted federal and state governments to generate guidelines for phosphorus management on certain agricultural operations. Pennsylvania’s Nutrient Management Program (Act 38 of 2005), the Concentrated Animal Feedin...

  9. NATIONAL PHOSPHORUS RUNOFF PROJECT: NEW HAMPSHIRE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The National Phosphorus Research Project was developed to coordinate research on the interaction between agricultural management and agricultural phosphorus pollution. As part of the Project, rainfall/runoff experiments were conducted on a Marlow soil in New Hampshire to assess the effects of soil ...

  10. Phosphorus Availability Coefficients from Various Organic Sources

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this study were to determine Phosphorus Availability Coefficients (PACs) for a variety of organic phosphorus (P) sources, and to examine the relationship between PACs measured in simulated rainfall runoff and alternative soil incubations. PAC is an important parameter in the P-Ind...

  11. NATIONAL PHOSPHORUS RUNOFF PROJECT: NEW YORK

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The National Phosphorus Research Project was developed to coordinate research on the interaction between agricultural management and agricultural phosphorus pollution. As part of the Project, rainfall/runoff experiments were conducted on a variety of New York soils to assess the effects of soil tes...

  12. PHOSPHORUS MANAGEMENT AND WATER QUALITY PROTECTION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) is an essential nutrient for growth of crops and aquatic vegetation. Phosphorus often needs to be applied to the land for optimal crop growth. Land application of P as animal manure, biosolids (sewage sludge), and mineral fertilizer can increase the risk of P pollution of freshwater. ...

  13. PHOSPHORUS CONTENT OF WATERS ALONG THE WEST COAST OF FLORIDA

    E-print Network

    during the "red tide" of 19U6-19U7. There is no evi- dence that either leaching from the bottom. However^ values of total phosphorus comparable to those of the red tide were found in blooms. .............. Phosphorus sections ........ Total phosphorus in column. Phosphorus and red tide. ......... Summary

  14. MEETING PHOSPHORUS REQUIREMENTS OF RUMINANTS IN AN ENVIRONMENTALLY RESPONSIBLE WAY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus entering lakes and streams from agricultural activity is a major stimulant to algae growth. The livestock industry, through soil application of manure, is a significant contributor of this phosphorus. One way to reduce phosphorus content of manure is to feed phosphorus to meet the anima...

  15. Labile Soil Phosphorus as Influenced by Methods of

    E-print Network

    AND METHODS 6 2.1. Laboratory experiment (E-values) ....> 6 2.2. Pot experiment (L-value) 8 3. RESULTSLabile Soil Phosphorus as Influenced by Methods of Applying Radioactive Phosphorus Vilma V PHOSPHORUS AS INFLUENCED BY METHODS OF APPLYING RADIOACTIVE PHOSPHORUS 1) 2) Vilma V. Selvaratnam , Senay

  16. A Hybrid Phosphorus Ligand for Highly Enantioselective Asymmetric Hydroformylation

    E-print Network

    Zhang, Xumu

    A Hybrid Phosphorus Ligand for Highly Enantioselective Asymmetric Hydroformylation Yongjun Yan phosphorus ligand has been prepared starting from chiral NOBIN (2-amino-2- hydroxy-1,1-binaphthyl). Excellent phosphorus ligands bearing two different phosphorus groups are effective in asymmetric hydroformylation.2a

  17. Bronx River bed sediments phosphorus pool and phosphorus compound identification

    NASA Astrophysics Data System (ADS)

    Wang, J.; Pant, H. K.

    2008-12-01

    Phosphorus (P) transport in the Bronx River degraded water quality, decreased oxygen levels, and resulted in bioaccumulation in sediment potentially resulting in eutrophication, algal blooms and oxygen depletion under certain temperature and pH conditions. The anthropogenic P sources are storm water runoff, raw sewage discharge, fertilizer application in lawn, golf course and New York Botanical Garden; manure from the Bronx zoo; combined sewoverflows (CSO's) from parkway and Hunts Point sewage plant; pollutants from East River. This research was conducted in the urban river system in New York City area, in order to control P source, figure out P transport temporal and spatial variations and the impact on water quality; aimed to regulate P application, sharing data with Bronx River Alliance, EPA, DEP and DEC. The sediment characteristics influence the distribution and bioavailbility of P in the Bronx River. The P sequential extraction gave the quantitative analysis of the P pool, quantifying the inorganic and organic P from the sediments. There were different P pool patterns at the 15 sites, and the substantial amount of inorganic P pool indicated that a large amount P is bioavailable. The 31P- NMR (Nuclear Magnetic Resonance Spectroscopy) technology had been used to identify P species in the 15 sites of the Bronx River, which gave a qualitative analysis on phosphorus transport in the river. The P compounds in the Bronx River bed sediments are mostly glycerophophate (GlyP), nucleoside monophosphates (NMP), polynucleotides (PolyN), and few sites showed the small amount of glucose-6-phosphate (G6P), glycerophosphoethanoamine (GPEA), phosphoenopyruvates (PEP), and inosine monophosphate (IMP). The land use spatial and temporal variations influence local water P levels, P distributions, and P compositions.

  18. Emerging technology for utilizing phosphorus sludge

    SciTech Connect

    Barber, J.C. [James C. Barber and Associates, Inc., Florence, AL (United States)

    1995-12-31

    This paper outlines a program at the Tennessee Valley Authority plant in Muscle Shoals, Alabama, to recycle phosphorus sludge produced by phosphate smelting. The recovery of phossy water and elemental phosphorus is addressed, as well as the recycle of inorganic solids from precipitator dust. Two processes for phossy water recycle were developed, which included separating phosphorus sludge from phossy water, waste clarification, and fluorine concentration control. The phossy water was used to make orthophosphate suspension fertilizer. For the recovery of elemental phosphorus, centrifuging and distillation were investigated. Centrifuging recovered 80 percent of the phosphorus in the sludge, but was difficult to operate and emitted toxic fumes. The pilot plant still did not completely volatilize the phosphorus, but was an improvement over other industry stills. A patented process for recycling precipitator dust is briefly described. It is estimated that the waste processing and recovery program will have a value of approximately $100 million, including the value of elemental phosphorus and the recovery of 93 acres of land.

  19. [Optimization and comparison of nitrogen and phosphorus removal by different aeration modes in oxidation ditch].

    PubMed

    Guo, Chang-Zi; Peng, Dang-Cong; Cheng, Xue-Mei; Wang, Dan

    2012-03-01

    The oxidation ditch operation mode was simulated by sequencing batch reactor (SBR) system with alternate stirring and aeration. The nitrogen and phosphorus removal efficiencies were investigated in two different aeration modes: point aeration and step aeration. Experimental results show that oxygen is dissolved more efficiently in point aeration mode with a longer aerobic region in the same air supply capacity, but dissolved oxygen (DO) utilization efficiency for nitrogen and phosphorus removal is high in step aeration mode. Nitrification abilities of the two modes are equal with ammonia-nitrogen (NH4(+) -N) removal efficiency of 96.68% and 97.03%, respectively. Nitrifier activities are 4.65 and 4.66 mg x (g x h)(-1) respectively. When the ratio of anoxic zones and the aerobic zones were 1, the total nitrogen (TN) removal efficiency of point aeration mode in 2, 4 or 7 partitions was respectively 60.14%, 47.93% and 33.7%. The total phosphorus (TP) removal efficiency was respectively 28.96%, 23.75% and 24.31%. The less the partitions, the higher the nitrogen and phosphorus removal efficiencies, but it is in more favor of TN removal. As for step aeration mode with only one partitioning zone, the TN and TP removal efficiencies are respectively 64.21% and 49.09%, which is better than in point aeration mode, but more conducive to the improvement of TP removal efficiency. Under the condition of sufficient nitrification in step aeration mode, the nitrogen and phosphorus removal is better with the increase of anoxic zone. The removal efficiencies of TN and TP respectively rose to 73.94% and 54.18% when the ratio of anoxic zones and the aerobic zones was increased from 1 : 1 to 1. 8 : 1. As the proportion of anoxic zones was enlarged further, nitrification and operation stability were weakened so as to affect the nitrogen and phosphorus removal efficiencies. PMID:22624387

  20. Tillage System Effect on Vertical Phosphorus Stratification and Phosphorus Uptake of Winter Wheat, Winter Pea, and Spring Pea

    E-print Network

    Lawrence, Rick L.

    under a continuous rotation of small grains and oilseeds. Phosphorus fertilizer (either MAP or TSP with hoe-type openers at 12 in. row spacing. Phosphorus fertilizer (0-45-0) was applied at 22.5 lb P2O5/acTillage System Effect on Vertical Phosphorus Stratification and Phosphorus Uptake of Winter Wheat

  1. Effect of previous fertilization on phosphorus adsorption. Measurement of surface phosphorus by isotopic exchange

    SciTech Connect

    Lopez, S.C.; Barbaro, N.O.; De Tramontini, S.R. (Comision Nacional de Energia Atomica, Buenos Aires (Argentina))

    1990-09-01

    Adsorption properties of a soil with previous additions of different phosphate fertilizers were characterized by means of the Langmuir isotherm. The best correlation with the Langmuir isotherm was obtained for low added-phosphorus concentration and for conditions of different amounts of initial soil phosphorus treatment. The phosphorus initially present in each soil sample was evaluated by isotopic exchange. (The use of different isotopic methodologies is discussed.) Carrier-free {sup 32}P was added to a soil-solution system in adsorption equilibrium after soil agitation with increasing phosphorus concentration solutions for 5 days; this allowed measurement of the adsorbed phosphorus that remained exchangeable phosphorus and equilibrium phosphorus concentration was found. The surface exchangeable phosphorus concentration at 0.3 ppm was used to estimate initial surface soil phosphorus. Taking these corrections into account, the authors found adsorption maximum and the bonding energy constant were similar in spite of the amount and kind of previous fertilizer addition. However, the behavior of superphosphate seemed to be modified in the presence of rock phosphate, especially in relation to exchange ability.

  2. Response of rice to soil phosphorus levels

    E-print Network

    Quddus, Mohammad Abdul

    1962-01-01

    RESPORSE OF RICE TO SOIL PHOSPHORUS LEVELS MOHJQRiD JL ~ QUDDUS Submitted te the Graduate Sohool of the kgrloultural and Mechanical College of Texas im partial fulfillment of the requirements for the legree of IGLSTER OF SCIENCE Luguet~ 1962... Eager Sub)cot& Agronomy RESPONSE OF RICE TO SOIL PHOSPHORUS LEVELS A Thesis KIHAMNAD Ae QUDDUS Approwed as to style and content by& Chairman of Committee Cpt r Head of Department August, 1962 ACKNOWLEDGMENTS The author wishes to express his...

  3. Phosphorus-based Monomers for Radical Polymerization

    Microsoft Academic Search

    Claudia Dworak; Christian Heller; Franz Varga; Robert Liska

    Our approach was to combine the excellent properties of phosphorus-containing polymers with a biodegradable, harmless polymer backbone. Therefore, we used polyvinylester and polyvinylcarbamate groups, as they are based on non-toxic poly(vinyl alcohol), which is left after degradation in biological environment. During this study we synthesized and characterized various types of phosphorus-containing vinylesters and vinylcarbamates (Figure 1). The reactivity of our

  4. Phosphorus removal and N?O production in anaerobic/anoxic denitrifying phosphorus removal process: long-term impact of influent phosphorus concentration.

    PubMed

    Wang, Zhen; Meng, Yuan; Fan, Ting; Du, Yuneng; Tang, Jie; Fan, Shisuo

    2015-03-01

    This study was conducted to investigate the long-term impact of influent phosphorus concentration on denitrifying phosphorus removal and N2O production during denitrifying phosphorous removal process. The results showed that, denitrifying phosphate accumulating organisms (DPAOs) could become dominant populations quickly in anaerobic/anoxic SBR by providing optimum cultivating conditions, and the reactor performed well for denitrifying phosphorus removal. The influent phosphorus concentration significantly affected anaerobic poly-?-hydroxyalkanoates (PHA) synthesis, denitrifying phosphorus removal, and N2O production during the denitrifying phosphorus removal process. As the influent phosphorus concentration was more than 20 mg L(-1), the activity of DPAOs began to be inhibited due to the transformation of the available carbon source type. Meanwhile, N2O production was inhibited with the mitigation of anoxic NO2(-)-N accumulation. Adoption of a modified feeding could enhance denitrifying phosphorus removal and inhibit N2O production during denitrifying phosphorous removal processes. PMID:25541320

  5. Estimate of dietary phosphorus intake using 24-h urine collection

    PubMed Central

    Morimoto, Yuuka; Sakuma, Masae; Ohta, Hiroyuki; Suzuki, Akitsu; Matsushita, Asami; Umeda, Minako; Ishikawa, Makoto; Taketani, Yutaka; Takeda, Eiji; Arai, Hidekazu

    2014-01-01

    Increases in serum phosphorus levels and dietary phosphorus intake induces vascular calcification, arterial sclerosis and cardiovascular diseases. Limiting phosphorus intake is advisable, however, no assessment methods are capable of estimating dietary phosphorus intake. We hypothesized that urinary phosphorus excretion can be translated into estimation of dietary phosphorus intake, and we evaluated whether a 24-h urine collection method could estimate dietary phosphorus intake. Thirty two healthy subjects were recruited for this study. Subjects collected urine samples over 24 h and weighed dietary records. We calculated dietary protein intake and phosphorus intake from dietary records and urine collection, and investigated associations between the two methods in estimating protein and phosphorus intake. Significant positive correlations were observed between dietary records and UC for protein and phosphorus intake. The average intakes determined from dietary records were significantly higher than from urine collection for both protein and phosphorus. There was a significant positive correlation between both the phosphorus and protein difference in dietary records and urine collection. The phosphorus-protein ratio in urine collection was significantly higher than in dietary records. Our data indicated that the 24-h urine collection method can estimate the amount of dietary phosphorus intake, and the results were superior to estimation by weighed dietary record. PMID:25120281

  6. Monitoring of phosphorus in Danish surface waters 1990-2012: Trends in phosphorus loading and phosphorus concentrations in streams, lakes and estuaries

    NASA Astrophysics Data System (ADS)

    Windolf, Jørgen; Kronvang, Brian; Carstensen, Jacob; Larsen, Søren E.; Bøgestrand, Jens; Trolle, Dennis

    2014-05-01

    For more than 20 years an integrated, standardized monitoring programme of Danish surface waters has provided information on status and trends in the phosphorus loading and phosphorus concentrations of Danish waters. Although the land-based phosphorus loading of Danish coastal waters has been reduced by 60For several decades the excess loading of phosphorus from diffuse sources and sewage outlets contributed significantly to the eutrophication of surface waters, and this is still the case. Measures taken to combat this eutrophication have included among others improved sewage treatment, diversion of sewage outlets from lakes and reduction of the phosphorus surplus on agricultural land. The overall effects of the measures taken to reduce the phosphorus loading and thereby improve the water quality will be presented for 15 Danish lakes and 10 estuaries and for 160 Danish streams draining catchments with varying anthropogenic impacts. The generally reduced phosphorus loading has led to a decrease in phosphorus concentrations in Danish lakes and estuaries due to the direct - long-term - link between phosphorus loading and phosphorus concentrations in lakes and estuaries. Special focus will be given to the development since 1990 in phosphorus concentrations in 31 streams draining farmed catchments with no significant sewage outlets and the potential factors influencing trends and variations. In 14 of these streams there has been a significant reduction in phosphorus concentrations since 1990, and for all the streams a general reduction of 17

  7. Rapid and portable electrochemical quantification of phosphorus.

    PubMed

    Kolliopoulos, Athanasios V; Kampouris, Dimitrios K; Banks, Craig E

    2015-04-21

    Phosphorus is one of the key indicators of eutrophication levels in natural waters where it exists mainly as dissolved phosphorus. Various analytical protocols exist to provide an offsite analysis, and a point of site analysis is required. The current standard method recommended by the Environmental Protection Agency (EPA) for the detection of total phosphorus is colorimetric and based upon the color of a phosphomolybdate complex formed as a result of the reaction between orthophosphates and molybdates ions where ascorbic acid and antimony potassium tartrate are added and serve as reducing agents. Prior to the measurements, all forms of phosphorus are converted into orthophosphates via sample digestion (heating and acidifying). The work presented here details an electrochemical adaptation of this EPA recommended colorimetric approach for the measurement of dissolved phosphorus in water samples using screen-printed graphite macroelectrodes for the first time. This novel indirect electrochemical sensing protocol allows the determination of orthophosphates over the range from 0.5 to 20 ?g L(-1) in ideal pH 1 solutions utilizing cyclic voltammetry with a limit of detection (3?) found to correspond to 0.3 ?g L(-1) of phosphorus. The reaction time and influence of foreign ions (potential interferents) upon this electroanalytical protocol was also investigated, where it was found that a reaction time of 5 min, which is essential in the standard colorimetric approach, is not required in the new proposed electrochemically adapted protocol. The proposed electrochemical method was independently validated through the quantification of orthophosphates and total dissolved phosphorus in polluted water samples (canal water samples) with ion chromatography and ICP-OES, respectively. This novel electrochemical protocol exhibits advantages over the established EPA recommended colorimetric determination for total phosphorus with lower detection limits and shorter experimental times. Additionally this electrochemical adaptation allows the determination of dissolved phosphorus without the use of ascorbic acid and antimony potassium tartrate as reducing agents (as used in the colorimetric method). The potential portability of this protocol is demonstrated in the development of the PhosQuant electrochemical device and provides a portable device for the rapid electrochemical detection of dissolved phosphorus using screen-printed electrodes. PMID:25856498

  8. MANAGING PHOSPHORUS-ENRICHED SOILS: EFFECTS OF IRON AMENDMENT ON TEMPORAL DYNAMICS OF BIOACTIVE PHOSPHORUS POOLS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An enzyme hydrolysis and soil phosphorus desorption study was conducted to determine whether the rate of buildup of manure inorganic and organic forms of phosphorus differs between soils and cropping systems. Water-extractable labile forms and complexed forms that are potentially bioactive were meas...

  9. Evaluation of Phosphorus Source Coefficients as Predictors of Runoff Phosphorus Concentrations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this study were to determine Phosphorus Source Coefficients (PSC) for organic phosphorus (P) sources, and to examine the relationship between PSCs and P concentrations measured in simulated rainfall runoff. The PSC is an important parameter in the P Site Index (PSI). An incubatio...

  10. DEVELOPMENT OF THE PHOSPHORUS LEACHING COMPONENT OF MARYLAND'S PHOSPHORUS SITE INDEX

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In Maryland, the loss of phosphorus (P) from agricultural soils has been identified as a major cause for the decline of water quality in the Chesapeake Bay. To decrease this P loss, Maryland's Water Quality Improvement Act requires nutrient management plans for virtually all farms. The Phosphorus Si...

  11. Carbon, sulfur, and phosphorus relations in oceanic Neogene sediments

    E-print Network

    Mays, Linda Lowry

    1987-01-01

    of pyritization (DOP), total phosphorus (nmol/g), organic phosphorus (smol/g), and C/P ratio at Site 532B. 24 Results for organic carbon, pyrite sulfur C/S ratio, acid-soluble iron, degree of pyritization (DOP), total phosphorus (smol/g), organic phosphorus... (rrmol/g), and C/P ratio at Site 654, 30 Results for organic carbon, pyrite sulfur C/S ratio, acid-soluble iron, degree of pyritization (DOP), total phosphorus (nmol/g), organic phosphorus (smol/g), and C/P ratio at Site 652. 36 LlST OF F...

  12. The renaissance of black phosphorus.

    PubMed

    Ling, Xi; Wang, Han; Huang, Shengxi; Xia, Fengnian; Dresselhaus, Mildred S

    2015-04-14

    One hundred years after its first successful synthesis in the bulk form in 1914, black phosphorus (black P) was recently rediscovered from the perspective of a 2D layered material, attracting tremendous interest from condensed matter physicists, chemists, semiconductor device engineers, and material scientists. Similar to graphite and transition metal dichalcogenides (TMDs), black P has a layered structure but with a unique puckered single-layer geometry. Because the direct electronic band gap of thin film black P can be varied from 0.3 eV to around 2 eV, depending on its film thickness, and because of its high carrier mobility and anisotropic in-plane properties, black P is promising for novel applications in nanoelectronics and nanophotonics different from graphene and TMDs. Black P as a nanomaterial has already attracted much attention from researchers within the past year. Here, we offer our opinions on this emerging material with the goal of motivating and inspiring fellow researchers in the 2D materials community and the broad readership of PNAS to discuss and contribute to this exciting new field. We also give our perspectives on future 2D and thin film black P research directions, aiming to assist researchers coming from a variety of disciplines who are desirous of working in this exciting research field. PMID:25820173

  13. 33 CFR 142.33 - Foot protection.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Foot protection. 142.33 Section 142...Personal Protective Equipment § 142.33 Foot protection. (a) Personnel working...where there is a reasonable probability for foot injury to occur shall wear...

  14. 33 CFR 142.33 - Foot protection.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Foot protection. 142.33 Section 142...Personal Protective Equipment § 142.33 Foot protection. (a) Personnel working...where there is a reasonable probability for foot injury to occur shall wear...

  15. 33 CFR 142.33 - Foot protection.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Foot protection. 142.33 Section 142...Personal Protective Equipment § 142.33 Foot protection. (a) Personnel working...where there is a reasonable probability for foot injury to occur shall wear...

  16. 33 CFR 142.33 - Foot protection.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Foot protection. 142.33 Section 142...Personal Protective Equipment § 142.33 Foot protection. (a) Personnel working...where there is a reasonable probability for foot injury to occur shall wear...

  17. 33 CFR 142.33 - Foot protection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Foot protection. 142.33 Section 142...Personal Protective Equipment § 142.33 Foot protection. (a) Personnel working...where there is a reasonable probability for foot injury to occur shall wear...

  18. Gastrointestinal Inhibition of Sodium-Hydrogen Exchanger 3 Reduces Phosphorus Absorption and Protects against Vascular Calcification in CKD.

    PubMed

    Labonté, Eric D; Carreras, Christopher W; Leadbetter, Michael R; Kozuka, Kenji; Kohler, Jill; Koo-McCoy, Samantha; He, Limin; Dy, Edward; Black, Deborah; Zhong, Ziyang; Langsetmo, Ingrid; Spencer, Andrew G; Bell, Noah; Deshpande, Desiree; Navre, Marc; Lewis, Jason G; Jacobs, Jeffrey W; Charmot, Dominique

    2014-11-17

    In CKD, phosphate retention arising from diminished GFR is a key early step in a pathologic cascade leading to hyperthyroidism, metabolic bone disease, vascular calcification, and cardiovascular mortality. Tenapanor, a minimally systemically available inhibitor of the intestinal sodium-hydrogen exchanger 3, is being evaluated in clinical trials for its potential to (1) lower gastrointestinal sodium absorption, (2) improve fluid overload-related symptoms, such as hypertension and proteinuria, in patients with CKD, and (3) reduce interdialytic weight gain and intradialytic hypotension in ESRD. Here, we report the effects of tenapanor on dietary phosphorous absorption. Oral administration of tenapanor or other intestinal sodium-hydrogen exchanger 3 inhibitors increased fecal phosphorus, decreased urine phosphorus excretion, and reduced [(33)P]orthophosphate uptake in rats. In a rat model of CKD and vascular calcification, tenapanor reduced sodium and phosphorus absorption and significantly decreased ectopic calcification, serum creatinine and serum phosphorus levels, circulating phosphaturic hormone fibroblast growth factor-23 levels, and heart mass. These results indicate that tenapanor is an effective inhibitor of dietary phosphorus absorption and suggest a new approach to phosphate management in renal disease and associated mineral disorders. PMID:25404658

  19. Phosphorus cycling in the Early Aptian

    NASA Astrophysics Data System (ADS)

    Oakes, R.; Dittrich, M.; Wortmann, U. G.

    2012-12-01

    Phosphorus is an essential nutrient for living organisms. It is vital for the formation of ATP, the energy store in cells, and is needed for DNA synthesis. Seawater phosphorus concentration therefore plays a critical role in controlling marine productivity on geological timescales. The majority of research on the P cycle focuses on modern lacustrine and marine settings. This follows the necessity to gain a further understanding on the effects of agricultural fertilisers on nutrient cycling; in particular on the mechanisms which lead to eutrophication. These studies use sequential extraction to determine the speciation of P. The results suggest that bottom sediments can act as both a source and a sink of phosphorus; the role they assume depends on range of factors including bottom water oxygen concentrations, sedimentation rate and the concentration of iron. This study applies a sequential extraction method developed in modern sediments to sediments from the Early Cretaceous, specifically the Early Aptian. During this time, globally synchronous oceanic anoxic events (OAE's) appear in the rock record. It has been suggested that these events represent an increase in marine productivity combined with bottom water anoxia. Our study investigates whether the speciation of sedimentary phosphorus can be used to reconstruct P cycling at this time. Our samples are taken from pre-, syn- and post-OAE1a but are not from the organic matter rich layers. Our results show that the original fractions of phosphorus have been altered during diagenesis with the majority of phosphorus now being preserved as either apatite (Ca-P) or phosphorus in organic matter (Porg). The dominance of Ca-P is expected as it is thought that redox-sensitive forms of P undergo 'sink switching' during diagenesis and are preserved as Ca-P. The high concentration of Porg however, differs from previous studies which generally find that Ca-P or iron (oxyhydr)oxide associated phosphorus (Fe-P) are dominant depending on deposition conditions. We find that during the anoxic event Ca-P preservation is enhanced, a trend which is not mirrored by an increase in total phosphorus concentration. This suggests that the formation of authigenic apatite via sink switching may have been enhanced during OAE1a. This agrees with the findings of a modern field and lab based study which proposes that more P is fixed than regenerated under anoxic conditions but contradicts earlier studies which suggest that more P will be refluxed from sediments under anoxic bottom-water conditions.

  20. Dietary phosphorus requirement of juvenile red drum, Sciaenops ocellatus

    E-print Network

    Davis, Donald Allen

    1986-01-01

    and black sea bream but moderately available to rainbow trout (NRC 1983) . Phosphorus in anchovy and menhaden fish meal is approximately 40 percent available to channel catfish (Lovell 1978) . Phytate, the major form of phosphorus in plants, has a very...

  1. Novel Mechanisms in the Regulation of Phosphorus Homeostasis

    NSDL National Science Digital Library

    Theresa Berndt (Mayo Clinic)

    2009-02-01

    Phosphorus plays a critical role in diverse biological processes, and, therefore, the regulation of phosphorus balance and homeostasis are critical to the well being of the organism. Changes in environmental, dietary, and serum concentrations of inorganic phosphorus are detected by sensors that elicit changes in cellular function and alter the efficiency by which phosphorus is conserved. Short-term, post-cibal responses that occur independently of hormones previously thought to be important in phosphorus homeostasis may play a larger role than previously appreciated in the regulation of phosphorus homeostasis. Several hormones and regulatory factors such as the vitamin D endocrine system, parathyroid hormone, and the phosphatonins (FGF-23, sFRP-4, MEPE) among others, may play a role only in the long-term regulation of phosphorus homeostasis. In this review, we discuss how organisms sense changes in phosphate concentrations and how changes in hormonal factors result in the conservation or excretion of phosphorus.

  2. 21 CFR 862.1580 - Phosphorus (inorganic) test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 false Phosphorus (inorganic) test system. 862.1580...MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1580 Phosphorus (inorganic) test system. (a)...

  3. 21 CFR 862.1580 - Phosphorus (inorganic) test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 false Phosphorus (inorganic) test system. 862.1580...MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1580 Phosphorus (inorganic) test system. (a)...

  4. 21 CFR 862.1580 - Phosphorus (inorganic) test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 false Phosphorus (inorganic) test system. 862.1580...MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1580 Phosphorus (inorganic) test system. (a)...

  5. Phosphorus: Tips for People with Chronic Kidney Disease (CKD)

    MedlinePLUS

    ... r ney D u ise s ase (CKD) National Kidney Disease Education Program What Is Phosphorus? Phosphorus is a ... and Human Services National Institutes of Health National Kidney Disease Education Program 2

  6. Phosphorus--Too Much and Plants May Suffer

    E-print Network

    Provin, Tony; Pitt, John L.

    2008-05-09

    The buildup of phosphorus in lawns, gardens, pastures and croplands can cause plants to grow poorly and even die. This publication explains how to identify problems caused by excessive phosphorus and how to correct those problems....

  7. Biological phosphorus removal from a phosphorus-rich dairy processing wastewater.

    PubMed

    Bickers, P O; Bhamidimarri, R; Shepherd, J; Russell, J

    2003-01-01

    Dairy industry processing wastewaters consist mainly of dilutions of milk, milk products and cleaning solutions and, depending on the processes used, may be rich in phosphorus. In New Zealand and internationally, chemical removal of phosphorus is typically the phosphorus removal method of choice from dairy processing wastewaters. The enhanced biological phosphorus removal (EBPR) process was investigated in this study as an alternative phosphorus removal option using a continuous activated sludge system. A synthetic dairy processing wastewater was firstly subjected to fermentation in an anaerobic reactor (HRT = 12 hrs, pH = 6.5, temperature = 35 degrees C) resulting in a fermented wastewater with an average volatile fatty acid (VFA) concentration of 1055 mg COD/L. The activated sludge reactor was operated in an AO configuration with an HRT of 2.5 days and an SRT of 15 days. Stable EBPR was exhibited with 42 mg P/L removed, resulting in a final sludge phosphorus content of 4.9% mg P/mg TSS. In the anaerobic zone (HRT = 2.85 hrs) the sludge had a phosphorus content of 3.16% mg P/mg TSS and a poly-beta-hydroxyalkanoate (PHA) concentration of 86 mg COD/g TS. PMID:14682569

  8. Reduction of dietary phosphorus absorption by phosphorus binders. A theoretical, in vitro, and in vivo study.

    PubMed Central

    Sheikh, M S; Maguire, J A; Emmett, M; Santa Ana, C A; Nicar, M J; Schiller, L R; Fordtran, J S

    1989-01-01

    Antacids used to decrease phosphorus absorption in patients with renal failure may be toxic. To find more efficient or less toxic binders, a three-part study was conducted. First, theoretical calculations showed that phosphorus binding occurs in the following order of avidity: Al3+ greater than H+ greater than Ca2+ greater than Mg2+. In the presence of acid (as in the stomach), aluminum can therefore bind phosphorus better than calcium or magnesium. Second, in vitro studies showed that the time required to reach equilibrium varied from 10 min to 3 wk among different compounds, depending upon solubility in acid and neutral solutions. Third, the relative order of effectiveness of binders in vivo was accurately predicted from theoretical and in vitro results; specifically, calcium acetate and aluminum carbonate gel were superior to calcium carbonate or calcium citrate in inhibiting dietary phosphorus absorption in normal subjects. We concluded that: (a) inhibition of phosphorus absorption by binders involves a complex interplay between chemical reactions and ion transport processes in the stomach and small intestine; (b) theoretical and in vitro studies can identify potentially better in vivo phosphorus binders; and (c) calcium acetate, not previously used for medical purposes, is approximately as efficient as aluminum carbonate gel and more efficient as a phosphorus binder than other currently used calcium salts. PMID:2910921

  9. Phosphorus and intraspecific density alter plant responses to arbuscular mycorrhizas

    Microsoft Academic Search

    Michelle S. Schroeder; David P. Janos

    2004-01-01

    We investigated how phosphorus availability, intraspecific density, and their interaction affect plant responses to arbuscular\\u000a mycorrhizas. Four facultatively mycotrophic species: chile, cilantro, tomato, and corn were examined separately in pot experiments\\u000a that employed a tropical phosphorus-immobilizing soil. Each experiment comprised nine soluble phosphorus additions, two levels\\u000a of intraspecific plant density, and inoculation with arbuscular mycorrhizal fungi or not. High phosphorus

  10. Phosphorus removal from domestic wastewater by Echinodorus cordifolius L

    Microsoft Academic Search

    Jirawan Torit; Wipawan Siangdung; Paitip Thiravetyan

    2012-01-01

    This study was to use the plants to remove phosphorus from domestic wastewater which contained high phosphorus concentration. Six higher plant species such as Crinum asiaticum L., Echinodorus cordifolius L., Spathiphyllum clevelandii Schott, Rhizophora apiculata Blume, Thalia dealbata J.fraser., Heliconia psittacorum L.f. were screened for phosphorus removal. Plants were grown in the domestic wastewater and the remaining phosphorus-phosphate concentration in

  11. Phosphorus-containing macrocyclic compounds: synthesis and properties

    NASA Astrophysics Data System (ADS)

    Knyazeva, I. R.; Burilov, Alexander R.; Pudovik, Michael A.; Habicher, Wolf D.

    2013-02-01

    Main trends in the development of methods for the synthesis of phosphorus-containing macrocyclic compounds in the past 15 years are considered. Emphasis is given to reactions producing macrocyclic structures with the participation of a phosphorus atom and other functional groups involved in organophosphorus molecules and to modifications of macrocycles by phosphorus compounds in different valence states. Possibilities of the practical application of phosphorus-containing macrocyclic compounds in difference areas of science and engineering are discussed. The bibliography includes 205 references.

  12. Electric field effect in ultrathin black phosphorus

    NASA Astrophysics Data System (ADS)

    Koenig, Steven P.; Doganov, Rostislav A.; Schmidt, Hennrik; Castro Neto, A. H.; Özyilmaz, Barbaros

    2014-03-01

    Black phosphorus exhibits a layered structure similar to graphene, allowing mechanical exfoliation of ultrathin single crystals. Here, we demonstrate few-layer black phosphorus field effect devices on Si/SiO2 and measure charge carrier mobility in a four-probe configuration as well as drain current modulation in a two-point configuration. We find room-temperature mobilities of up to 300 cm2/Vs and drain current modulation of over 103. At low temperatures, the on-off ratio exceeds 105, and the device exhibits both electron and hole conduction. Using atomic force microscopy, we observe significant surface roughening of thin black phosphorus crystals over the course of 1 h after exfoliation.

  13. Electric field effect in ultrathin black phosphorus

    SciTech Connect

    Koenig, Steven P.; Schmidt, Hennrik [Graphene Research Centre, National University of Singapore, 6 Science Drive 2, Singapore 117546 (Singapore); Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542 (Singapore); Doganov, Rostislav A.; Castro Neto, A. H.; Özyilmaz, Barbaros [Graphene Research Centre, National University of Singapore, 6 Science Drive 2, Singapore 117546 (Singapore); Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542 (Singapore); Graduate School for Integrative Sciences and Engineering (NGS), National University of Singapore, 28 Medical Drive, Singapore 117456 (Singapore)

    2014-03-10

    Black phosphorus exhibits a layered structure similar to graphene, allowing mechanical exfoliation of ultrathin single crystals. Here, we demonstrate few-layer black phosphorus field effect devices on Si/SiO{sub 2} and measure charge carrier mobility in a four-probe configuration as well as drain current modulation in a two-point configuration. We find room-temperature mobilities of up to 300 cm{sup 2}/Vs and drain current modulation of over 10{sup 3}. At low temperatures, the on-off ratio exceeds 10{sup 5}, and the device exhibits both electron and hole conduction. Using atomic force microscopy, we observe significant surface roughening of thin black phosphorus crystals over the course of 1 h after exfoliation.

  14. Flammability of Epoxy Resins Containing Phosphorus

    NASA Technical Reports Server (NTRS)

    Hergenrother, P. M.; Thompson, C. M.; Smith, J. G.; Connell, J. W.; Hinkley, J. A.

    2005-01-01

    As part of a program to develop fire-resistant exterior composite structures for future subsonic commercial and general aviation aircraft, flame-retardant epoxy resins are under investigation. Epoxies and their curing agents (aromatic diamines) containing phosphorus were synthesized and used to prepare epoxy formulations. Phosphorus was incorporated within the backbone of the epoxy resin and not used as an additive. The resulting cured neat epoxy formulations were characterized by thermogravimetric analysis, propane torch test, elemental analysis, microscale combustion calorimetry, and fire calorimetry. Several formulations showed excellent flame retardation with phosphorous contents as low as 1.5% by weight. The fracture toughness and compressive strength of several cured formulations showed no detrimental effect due to phosphorus content. The chemistry and properties of these new epoxy formulations are discussed.

  15. Effects of white phosphorus on mallard reproduction

    USGS Publications Warehouse

    Vann, S.I.; Sparling, D.W.; Ottinger, M.A.

    2000-01-01

    Extensive waterfowl mortality involving thousands of ducks, geese, and swans has occurred annually at Eagle River Flats, Alaska since at least 1982. The primary agent for this mortality has been identified as white phosphorus. Although acute and subacute lethality have been described, sublethal effects are less well known. This study reports on the effects of white phosphorus on reproductive function in the mallard (Anas platyrhynchos) in captivity. Fertility, hatching success, teratogenicity, and egg laying frequency were examined in 70 adult female mallards who received up to 7 daily doses of 0, 0.5, 1.0, and 2.0 mg/kg of white phosphorus. Measurements of fertility and hatchability were reduced by the white phosphorus. Teratogenic effects were observed in embryos from hens dosed at all treatment levels. Egg laying frequency was reduced even at the lowest treatment level; treated hens required a greater number of days to lay a clutch of 12 eggs than control hens. After two doses at 2.0 mg/kg, all females stopped laying completely for a minimum of 10 days and laying frequency was depressed for at least 45 days. Fertility of 10 adult male mallards dosed with 1.0 mg/kg of white phosphorus did not differ from 10 controls, but plasma testosterone levels were significantly (p < 0.05) reduced in the treated males 1 day after dosing ended. These results provide evidence that productivity of free-ranging mallards may be impaired if they are exposed to white phosphorus at typical field levels.

  16. Chemical fractionation and solubility of phosphorus in dairy manure-amended soils as a predictor of phosphorus concentration in runoff

    E-print Network

    Harstad, Laura Elizabeth

    2007-04-25

    ....................................................................................... 3 Eutrophication............................................................................................ 3 Forms of Phosphorus ................................................................................. 5 History of P... size distribution and textural class for each soil................................. 27 3 Phosphorus concentrations and corresponding transmittances for the standard curve...

  17. INTERNAL PHOSPHORUS LOADING IN A SHALLOW EUTROPHIC LAKE (JOURNAL VERSION)

    EPA Science Inventory

    Internal loading of phosphorus has been implicated as a major eutrophication factor in Long Lake, WA. As a result of such loading, summer total phosphorus concentrations approach or exceed 100 micrograms P/l. Most of the summer loading of phosphorus is thought to have been releas...

  18. The absorption of dietary phosphorus and calcium in hemodialysis patients

    Microsoft Academic Search

    J Arnaldo Ramirez; Michael Emmett; Martin G White; Nastaran Fathi; Carol A Santa Ana; Stephen G Morawski; John S Fordtran

    1986-01-01

    The absorption of dietary phosphorus and calcium in hemodialysis patients. Absorption of dietary phosphorus plays a critical role in the development of metabolic bone diseases in patients with chronic renal failure. However, phosphorus absorption is difficult to quantitate in dialysis patients because the dialysis treatments complicate metabolic balance studies. Utilizing a recently developed technique which permits measurement of net absorption

  19. Soil phosphorus dynamics under sprinkler and furrow irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Furrow irrigation detaches and transports soil particles and subsequently nutrients such as phosphorus. To reduce the risk of erosion and offsite phosphorus movement, producers can convert from furrow to sprinkler irrigation. We completed research on soil phosphorus dynamics in furrow versus sprin...

  20. Comparison of arsenic and phosphorus diffusion behavior in silicongermanium alloys

    E-print Network

    Comparison of arsenic and phosphorus diffusion behavior in silicon­germanium alloys S. Eguchia of ion-implanted arsenic and phosphorus in relaxed Si0.8Ge0.2 has been investigated. Under equilibrium is roughly seven for arsenic, and roughly two for phosphorus. Under transient diffusion conditions

  1. EVALUATION OF A PROTOTYPE INSTRUMENT FOR DETERMINING PHOSPHORUS IN WATER

    EPA Science Inventory

    A second-generation flame spectrometer for the direct determination of phosphorus in water was evaluated. Response to phosphorus in the form of phosphoric acid was linear from 0.5 to 16 ppm phosphorus. The relative standard deviation was approximately constant at 20 percent over ...

  2. Using Oxygen Isotopes of Phosphate To Trace Phosphorus Sources and

    E-print Network

    Paytan, Adina

    Using Oxygen Isotopes of Phosphate To Trace Phosphorus Sources and Cycling in Lake Erie K A T Y E events in the hypolimnion of the central basin of Lake Erie. Identifying potential phosphorus sources favorable to hypoxia. Although point source contributions of phosphorus (P) to Lake Erie are strictly

  3. Soil, Water and Forage Testing Laboratory Phosphorus recommendations applicable for

    E-print Network

    Soil, Water and Forage Testing Laboratory Phosphorus recommendations applicable for methods used 20 15 5 0 #12;Soil, Water and Forage Testing Laboratory Phosphorus recommendations applicable by laboratory. Mehlich III by ICP only. Phosphorus Soil Fertility Recommendations for Oil Crops 0 5 10 15 20 25

  4. IDENTIFYING TOTAL PHOSPHORUS SPECTRAL SIGNAL IN A TROPICAL ESTUARY LAGOON

    E-print Network

    Gilbes, Fernando

    ) this study demonstrates the application of total phosphorus possible spectral indexes to monitor its contentIDENTIFYING TOTAL PHOSPHORUS SPECTRAL SIGNAL IN A TROPICAL ESTUARY LAGOON USING AN HYPERSPECTRAL phosphorus concentrations. A reflectance determination coefficient of 0.49 was obtained from the 467 to 529

  5. Incommensurate Structure of Phosphorus Phase IV

    SciTech Connect

    Fujihisa, Hiroshi; Gotoh, Yoshito; Yamawaki, Hiroshi; Sakashita, Mami; Takeya, Satoshi; Honda, Kazumasa [National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565 (Japan); Akahama, Yuichi; Kawamura, Haruki [Graduate School of Material Science, University of Hyogo, 3-2-1 Kouto, Kamigori, Ako-gun, Hyogo 678-1297 (Japan); Ohishi, Yasuo [Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1 Kouto, Mikazuki, Sayo-gun, Hyogo 679-5198 (Japan)

    2007-04-27

    There are six known phases for phosphorus at room temperature under high pressure. Only the structure of phase IV, which exists from 107 GPa to 137 GPa, remains unsolved. We performed a powder x-ray diffraction experiment and a Rietveld analysis and successfully determined its structure to be an incommensurately modulated structure by only 1 site of atomic position. High-pressure phases of halogens and chalcogens have previously been shown to have a similar modulated structure; however, phosphorus phase IV is different from them and was shown to be the third case.

  6. Occurrence of Arbuscular Mycorrhizal Fungi in a Phosphorus-Poor Wetland and Mycorrhizal Response to Phosphorus Fertilization

    Microsoft Academic Search

    William K. Cornwell; Barbara L. Bedford; Carmen T. Chapin

    2001-01-01

    The presence of arbuscular mycorrhizas in fens has received little attention, but because fen plants are often phosphorus limited, the plant-fungus interaction could be an important factor in plant competition for phosphorus. In this field study, we determined mycorrhizal colonization rates for 18 fen plant species. Also in the field, we examined the effect of four different forms of phosphorus

  7. Phosphorus Redox on the Early Earth: First Identification of Low-Oxidation State Phosphorus Compounds in Terrestrial Samples

    Microsoft Academic Search

    K. M. Block; M. A. Pasek

    2008-01-01

    Phosphorus is one of the key elements in biochemical systems, playing an important role in metabolism as ATP and other coenzymes, in replication as DNA and RNA, and in cellular structure as phospholipids. The geochemical cycling of phosphorus on the Earth is usually confined to the rock cycle- redox reactions of phosphorus are never considered. However, it has been proposed

  8. Competition for phosphorus: differential uptake from dual-isotope--labeled soil interspaces between shrub and grass.

    PubMed

    Caldwell, M M; Eissenstat, D M; Richards, J H; Allen, M F

    1985-07-26

    Two species of Agropyron grass differed strikingly in their capacity to compete for phosphate in soil interspaces shared with a common competitor, the sagebrush Artemisia tridentata. Of the total phosphorus-32 and -33 absorbed by Artemisia, 86 percent was from the interspace shared with Agropyron spicatum and only 14 percent from that shared with Agropyron desertorum. Actively absorbing mycorrhizal roots of Agropyron and Artemisia were present in both interspaces, where competition for the labeled phosphate occurred. The results have important implications about the way in which plants compete for resources below ground in both natural plant communities and agricultural intercropping systems. PMID:17795898

  9. Competition for phosphorus: differential uptake from dual-isotope-labeled soil interspaces between shrub and grass

    SciTech Connect

    Caldwell, M.M.; Eissenstat, D.M.; Richards, J.H.; Allen, M.F.

    1985-07-26

    Two species of Agropyron grass differed strikingly in their capacity to compete for phosphate in soil interspaces shared with a common competitor, the sagebrush Artemisia tridentata. Of the total phosphorus-32 and -33 absorbed by Artemisia, 86% was from the interspace shared with Agropyron spicatum and only 14% from that shared with Agropyron desertorum. Actively absorbing mycorrhizal roots of Agropyron and Artemisia were present in both interspaces, where competition for the labeled phosphate occurred. The results have important implications about the way in which plants compete for resources below ground in both natural plant communities and agricultural intercropping systems.

  10. [Vertical distribution patterns of nitrogen, phosphorus, and potassium in Chinese pine forest soils developed from different parent materials in Songshan Mountain Nature Reserve, Beijing of China].

    PubMed

    Gou, Li-hui; Sun, Zhao-di; Nie, Li-shui; Luo, Pan-pan; Wu, Ji-Gui; Xu, Wu-de

    2013-04-01

    Taking the soils developed from two kinds of parent materials (granite and limestone) under Pinus tabulaeformis forest at the same altitude in Songshan Mountain Nature Reserve of Beijing as test objects, this paper studied the vertical distribution patterns of soil total nitrogen, available phosphorus, and available potassium. The soil developed from granite had the total nitrogen, available phosphorus, and available potassium contents being 1.61-2. 35 g kg-1, 5. 84-10.74 mg kg- 1, and 39.33-93.66 mg kg-1, while that developed from limestone had the total nitrogen, available phosphorus, and available potassium contents being 1. 69 -2. 36 g kg-1, 4.45-8.57 mg . kg-1, and 60.66-124.00 mg kg-1, respectively. The total nitrogen, available phosphorus, and available potassium contents in the two soils were the highest in 0-10 cm layer, decreased with increasing depth, and had significant differences between different layers, showing that the soil total nitrogen, available phosphorus, and available potassium had a strong tendency to accumulate in surface layer. Such a tendency was more obvious for the soil developed from limestone. The paired t-test for the two soils indicated that the total nitrogen content in different layers had no significant difference, whereas the available phosphorus content in 0-10 cm layer and the available potassium content in 10-20 cm layer differed significantly. PMID:23898652

  11. Phosphorus vacancy cluster model for phosphorus diffusion gettering of metals in Si

    SciTech Connect

    Chen, Renyu; Trzynadlowski, Bart; Dunham, Scott T. [Department of Electrical Engineering, University of Washington, Seattle, Washington 98195 (United States)

    2014-02-07

    In this work, we develop models for the gettering of metals in silicon by high phosphorus concentration. We first performed ab initio calculations to determine favorable configurations of complexes involving phosphorus and transition metals (Fe, Cu, Cr, Ni, Ti, Mo, and W). Our ab initio calculations found that the P{sub 4}V cluster, a vacancy surrounded by 4 nearest-neighbor phosphorus atoms, which is the most favorable inactive P species in heavily doped Si, strongly binds metals such as Cu, Cr, Ni, and Fe. Based on the calculated binding energies, we build continuum models to describe the P deactivation and Fe gettering processes with model parameters calibrated against experimental data. In contrast to previous models assuming metal-P{sub 1}V or metal-P{sub 2}V as the gettered species, the binding of metals to P{sub 4}V satisfactorily explains the experimentally observed strong gettering behavior at high phosphorus concentrations.

  12. Investigation into phosphorus removal by iron ochre for the potential treatment of aquatic phosphorus pollution 

    E-print Network

    Carr, Stephen Thomas David

    2012-11-29

    Phosphorus (P) pollution of waterbodies is a global issue with detrimental environmental, social and economic impacts. Low-cost and sustainable P removal technologies are therefore required to tackle P pollution, whilst ...

  13. Temporal dynamics of available and microbial phosphorus and organic phosphorus mineralization in a grassland soil

    NASA Astrophysics Data System (ADS)

    Liebisch, Frank; Keller, Fabrizio; Frossard, Emmanuel; Huguenin-Elie, Olivier; Oberson, Astrid; Bünemann, Else

    2010-05-01

    Turnover of phosphorus (P) through the microbial biomass and P mineralization have been reported as two main biological factors controlling P availability in soils. This is particularly true for grassland soils where organic matter is accumulated in the topsoil and microbial activity is high. The amounts of plant available inorganic P and microbial P can fluctuate over the season, but their interaction and responses to changes in environmental conditions, fertilization and cutting are not yet well understood. Also, gross P mineralization has not yet been measured in grassland soils. We studied P mineralization and immobilization in a species rich grassland managed at low intensity (with three harvests per season) under different P inputs. The trial was established in 1992 in Watt (Switzerland). Three different P input treatments were selected: no P (NK), mineral P (NPK) and organic P (NPKorg) fertilization, with 17 kg P ha-1yr-1 applied as superphosphate and slurry, respectively (rates according to Swiss fertilizer recommendations). We used two different approaches. Firstly, available (anion exchange resin extractable) and microbial P (hexanol labile P) were measured in fresh samples periodically taken throughout the vegetation period. Secondly, an isotopic dilution technique was applied on composite topsoil samples (0-5 cm) to determine rates of basal P mineralization and microbial immobilization of P in an incubation experiment. During the season available P ranged from 0.9-3.5, 5.3-11.2 and 1.9-6.7 mg kg-1 soil-1 and microbial P from 20-44, 43-59 and 61-93 mg kg-1 soil-1 in NK, NPK and NPKorg, respectively. Thus, microbial P was highest in NPKorg whereas available P was highest in NPK. Both P pools were lowest in NK. Average annual yield was lowest in NK (4.5 t ha-1), NPKorg (6.5 kg ha-1) and highest in NPK (7.5 t ha-1). However, no consistent relationship between changes in microbial and available P and plant productivity was found. Changes in weather conditions were reflected by changes in available and microbial P measured in the field. Phosphorus flushes were observed after dry periods (microbial P reduced and available P increased). Whereas fluctuations show microbial P release and P immobilization, an expected counteraction of microbial and available P could not be fully confirmed. In the incubation experiment microbial and available P were similar to average values in the field. A higher respiration rate measured in NPKorg indicated a higher microbial activity than in the other two treatments. Despite the differences in microbial P and respiration, the 33P recovery in the microbial biomass between 3 and 30 days of incubation was about 30% in all treatments. In conclusion we found complex interactions of available and microbial P with climate, fertilization, sward cutting and plant growth. An increased immobilization of P indicated by higher microbial P in the organic fertilized treatment was not confirmed in the isotope study. Gross and net mineralization data are still under analysis and will be presented at the conference.

  14. Pressure-induced crystallization of amorphous red phosphorus

    NASA Astrophysics Data System (ADS)

    Rissi, Erin N.; Soignard, Emmanuel; McKiernan, Keri A.; Benmore, Chris. J.; Yarger, Jeffery L.

    2012-03-01

    Structural transitions in amorphous red phosphorus were studied at ambient temperature and pressures up to 12 GPa. Amorphous (red) phosphorus was observed to transform into crystalline black phosphorus at 7.5 ± 0.5 GPa using diamond anvil cell Raman spectroscopy, x-ray diffraction and a direct equation of state (EoS) measurement. The transition was found to be irreversible and the material recovered upon pressure cycling to 10 to 12 GPa was crystalline orthorhombic black phosphorus. A third order Birch-Murnaghan EoS was fit to the data and a bulk modulus (B0) of 11.2 GPa was measured for amorphous red phosphorus.

  15. Lability of Humic-Bound Phosphorus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) has long been known to be present in humic substances from various sources. However, information on the lability of humic-bound P is very limited although such information is critical for understanding the role of humic substances in P cycling and nutrition. In this presentation, we d...

  16. PHOSPHORUS UPTAKE AND RELEASE FROM STREAM SEDIMENTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus runoff from agricultural fields has been linked to freshwater eutrophication. However, edge-of-field P losses can be modified by benthic sediments during channel flow by physiochemical processes associated with Al, Fe, and Ca, and by biological assimilation. Thus, we investigated fluvial ...

  17. Modeling Phosphorus in the Environment Review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) is a key component of fertilizer inputs in plant agriculture and a critical ingredient of diets in animal nutrition. Elevated levels of environmental P and nitrogen have often resulted in algal blooms and accelerated eutrophication of lakes and streams, and degrade fragile ecosystems...

  18. Inorganic Plant Nutrients: Nitrogen, Phosphorus, Silicate Introduction

    E-print Network

    Jochem, Frank J.

    Lab 3: Inorganic Plant Nutrients: Nitrogen, Phosphorus, Silicate Introduction Compounds of nitrogen base cations (calcium, magnesium, sodium, potassium) are generally in sufficient supply in seawater. Silicate can play a regulating role in the growth of such organisms that carry shells of silicate. Most

  19. Phosphorus recovery and reuse from waste streams

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) is an important macro-nutrient required by higher plants for growth and development. Phosphate rock is the main raw material for P fertilizers and the global rock phosphate production stands at 191,000 thousand tonnes (t) in the year 2011 (Jaisinski, 2012). Phosphate rock is a scarce ...

  20. Agricultural Management, Water Quality and Phosphorus

    E-print Network

    Agricultural Management, Water Quality and Phosphorus: The Long and Winding Road Andrew Sharpley #12;In the beginning Agriculture and water quality Targeted watershed P management Linking ecosystem;#12;Optimal soil PO concentrations for plant growth ~0.20 mg/L #12;For flowing waters ~0.01 to 0.10 mg/L #12

  1. EFFECT OF PHOSPHORUS TREATMENT ON LEAD MINERALOGY

    EPA Science Inventory

    Remediation of Pb-contaminated soils by amendments of phosphate may prove to be a viable way of sequestering Pb in the natural environment. Test plots of Pb-contaminated soil near Joplin, MO were treated with a variety of phosphorus-based amendments to observe the influence of co...

  2. DIETARY PHOSPHORUS LEVELS FOR DAIRY COWS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Manure application to cropland is becoming increasingly regulated based on a combination of manure phosphorus (P) content, soil test P level, crop P requirements and a field's risk to lose runoff P to surface water. Feeding P in excess of NRC-recommended levels does not increase milk production, mil...

  3. Promotion of root elongation by phosphorus deficiency

    Microsoft Academic Search

    M. Anuradha; A. Narayanan

    1991-01-01

    Decrease of culture solution pH and increase in cation\\/anion ratio in the plant were observed when horsegram (Macrotyloma uniflorum (Lam.) Verdc.) was grown in solution culture deficient in phosphorus. The effux of H+ from the roots of ?P plants was observed in bromocresol purple agar. The length of root cells was considerably increased by ?P treatment. Thus a close correlation

  4. Extractable soil phosphorus in Blackland Prairie soils

    E-print Network

    Byrd, Robert Claude

    1995-01-01

    The Texas Agricultural Extension Service (TAEX) Soil Testing Laboratory currently utilizes a single phosphorus (P) extractant consisting of 1.43 M NH4OAc, 1. 0 M HCl, and 0.025 M EDTA-PH 4.2 to estimate plant available P for all soils in Texas...

  5. SURVEY OF WATER EXTRACTABLE PHOSPHORUS IN MANURE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water-extractable phosphorus (P) in manure is strongly related to dissolved P in runoff from soils receiving recent additions of manure. A survey of water-extractable P concentrations in manures submitted to Penn State University's Agricultural Analytical Services Laboratory was conducted. Results r...

  6. EVALUATION OF PHOSPHORUS MANAGEMENT STRATEGIES IN PENNSYLVANIA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Farm management and financial impacts of three phosphorus (P) nutrient management strategies: soil test crop response (STCR), environmental soil P threshold (ESPT), and P Index (PI) outlined in the USDA and USEPA (1999) Unified Strategy for Animal Feeding Operations were evaluated on ten Pennsylvani...

  7. Phosphorus recovery and reuse from waste streams

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) is a macronutrient essential for all living organisms. Regrettably, it is a finite resource since phosphate rock (PR) is the main material used for production of P fertilizers. Globally, the demand for quality PR is escalating due to many factors including increasing human population....

  8. ESTIMATING SOURCE COEFFICIENTS FOR PHOSPHORUS SITE INDICES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) release to runoff varies widely for different land-applied organic-P sources even when applied at equivalent total P rates. To address this variability, some P site indices include tabulated P source coefficients (PSCs) for differential weighting of applied P materials based on their ...

  9. BIOLOGICAL PHOSPHORUS REMOVAL: A TECHNOLOGY EVALUATION

    EPA Science Inventory

    A study of alternative biological phosphorus (bio-P) removal processes was undertaken to evaluate their effectiveness and reliability. Thirty such facilities were identified in the United States and Canada. Four plants were selected for detailed study. The PhoStrip process is use...

  10. THE PENNSYLVANIA PHOSPHORUS INDEX: VERSION 1

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There has been increased attention focused on phosphorus (P) management because of water quality concerns resulting from eutrophication. In fresh water systems, elevated P inputs can lead to accelerated eutrophication and degraded water quality. Despite water quality concerns, adequate levels of s...

  11. EVALUATION OF THE ANNAGNPS PHOSPHORUS COMPONENT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The USDA Annualized Agricultural Non-Point Source Pollution model (AnnAGNPS) has been developed to aid in the evaluation of watershed response to agricultural management practices. The main purpose of this paper is to introduce AnnAGNPS phosphorus (P) component and evaluate the performance of AnnAG...

  12. Patient education for phosphorus management in chronic kidney disease

    PubMed Central

    Kalantar-Zadeh, Kamyar

    2013-01-01

    Objectives: This review explores the challenges and solutions in educating patients with chronic kidney disease (CKD) to lower serum phosphorus while avoiding protein insufficiency and hypercalcemia. Methods: A literature search including terms “hyperphosphatemia,” “patient education,” “food fatigue,” “hypercalcemia,” and “phosphorus–protein ratio” was undertaken using PubMed. Results: Hyperphosphatemia is a strong predictor of mortality in advanced CKD and is remediated via diet, phosphorus binders, and dialysis. Dietary counseling should encourage the consumption of foods with the least amount of inorganic or absorbable phosphorus, low phosphorus-to-protein ratios, and adequate protein content, and discourage excessive calcium intake in high-risk patients. Emerging educational initiatives include food labeling using a “traffic light” scheme, motivational interviewing techniques, and the Phosphate Education Program – whereby patients no longer have to memorize the phosphorus content of each individual food component, but only a “phosphorus unit” value for a limited number of food groups. Phosphorus binders are associated with a clear survival advantage in CKD patients, overcome the limitations associated with dietary phosphorus restriction, and permit a more flexible approach to achieving normalization of phosphorus levels. Conclusion: Patient education on phosphorus and calcium management can improve concordance and adherence and empower patients to collaborate actively for optimal control of mineral metabolism. PMID:23667310

  13. Quantifying phosphorus and light effects in stream algae

    SciTech Connect

    Hill, Walter [University of Illinois, Urbana-Champaign; Fanta, S.E. [University of Illinois; Roberts, Brian J [ORNL

    2009-01-01

    Simultaneous gradients of phosphorus and light were applied in experimental streams to develop quantitative relationships between these two important abiotic variables and the growth and composition of benthic microalgae. Algal biovolume and whole-stream metabolism responded hyperbolically to phosphorus enrichment, increasing approximately two-fold over the 5-300 g L-1 range of experimental phosphorus concentrations. The saturation threshold for phosphorus effects occurred at 25 g L-1 of soluble reactive phosphorus (SRP). Light effects were much stronger than those of phosphorus, resulting in a nearly ten-fold increase in algal biovolume over the 10-400 mol photons m-2 s-1 range of experimental irradiances. Biovolume accrual was light-saturated at 100 mol photons m-2 s-1 (5 mol photons m-2 d-1). Light effects were diminished by low phosphorus concentrations, and phosphorus effects were diminished by low irradiances, but evidence of simultaneous limitation by both phosphorus and light at subsaturating irradiances was weak. Contrary to the light:nutrient hypothesis, algal phosphorus content was not significantly affected by light, even in the lowest SRP treatments. However, algal nitrogen content increased substantially at lower irradiances, and it was very highly correlated with algal chlorophyll a content. Phosphorus enrichment in streams is likely to have its largest effect at concentrations <25 g L-1 SRP, but the effect of enrichment is probably minimized when streambed irradiances are kept below 2 mol photons m-2 d-1 by riparian shading or turbidity

  14. Effect of van der Waals interactions on the structural and elastic properties of black phosphorus

    NASA Astrophysics Data System (ADS)

    Appalakondaiah, S.; Vaitheeswaran, G.; Lebègue, S.; Christensen, N. E.; Svane, A.

    2012-07-01

    The structural and elastic properties of orthorhombic black phosphorus have been investigated using first-principles calculations based on density functional theory. The structural parameters have been calculated using the local density approximation (LDA), the generalized gradient approximation (GGA), and with several dispersion corrections to include van der Waals interactions. It is found that the dispersion corrections improve the lattice parameters over LDA and GGA in comparison with experimental results. The calculations reproduce well the experimental trends under pressure and show that van der Waals interactions are most important for the crystallographic b axis in the sense that they have the largest effect on the bonding between the phosphorus layers. The elastic constants are calculated and are found to be in good agreement with experimental values. The calculated C22 elastic constant is significantly larger than the C11 and C33 parameters, implying that black phosphorus is stiffer against strain along the a axis than along the b and c axes. From the calculated elastic constants, the mechanical properties, such as bulk modulus, shear modulus, Young's modulus, and Poisson's ratio are obtained. The calculated Raman active optical phonon frequencies and their pressure variations are in excellent agreement with available experimental results.

  15. Phosphorus limitation strategy to increase propionic acid flux towards 3-hydroxyvaleric acid monomers in Cupriavidus necator.

    PubMed

    Grousseau, Estelle; Blanchet, Elise; Déléris, Stéphane; Albuquerque, Maria G E; Paul, Etienne; Uribelarrea, Jean-Louis

    2014-02-01

    Properties of polyhydroxybutyrate-co-hydroxyvalerate (P(3HB-co-3HV)) depend on their 3HV content. 3HV can be produced by Cupriavidus necator from propionic acid. Few studies explored carbon distribution and dynamics of 3HV and 3HB monomers production, and none of them have been done with phosphorus as limiting nutrient. In this study, fed-batch cultures of C. necator with propionic acid, as sole carbon source or mixed with butyric acid, were performed. Phosphorus deficiency allowed sustaining 3HV production rate and decreasing 3HB production rate, leading to an instant production of up to 100% of 3HV. When a residual growth is sustained by a phosphorus feeding, the maximum 3HV percentage produced from propionic acid is limited to 33% (Mole.Mole(-1)). The association of a second carbon source like butyric acid lead to higher conversion of propionic acid into 3HV. This study showed the importance of the limiting nutrient and of the culture strategy to get the appropriate product. PMID:24365742

  16. Innovative Method for Separating Phosphorus and Iron from High-Phosphorus Oolitic Hematite by Iron Nugget Process

    NASA Astrophysics Data System (ADS)

    Han, Hongliang; Duan, Dongping; Wang, Xing; Chen, Siming

    2014-10-01

    This study puts forward a new method to separate phosphorus and iron from high-phosphorus oolitic hematite through iron nuggets process. Firstly, the physical, chemical, and microscopic characteristics of high-phosphorus oolitic hematite are investigated. Then, the reaction mechanisms of high-phosphorus hematite together with feasibility to separating phosphorus and iron by iron nugget process are discussed. Meanwhile, the experiments of high-phosphorus hematite used in rotary hearth furnace iron nugget processes are studied as well. The results indicate that the iron nugget process is a feasible and efficient method for iron and phosphorus separation of high-phosphorus oolitic hematite. The phosphorus content in iron nuggets is relatively low. Through the optimization of process parameters, the lowest of phosphorus in iron nuggets is 0.22 pct, the dephosphorization rate is above 86 pct, and the recovery of Fe is above 85 pct by the iron nugget process. This study aims to provide a theoretical and technical basis for economical and rational use of high-phosphorus oolitic hematite.

  17. Phosphorus retranslocation in Hordeum vulgare during early tillering.

    PubMed

    Greenway, H; Gunn, A

    1966-03-01

    In Hordeum vulgare, phosphorus retranslocation was studied after it had been supplied to the roots for three days (experiment 1), and after foliar application (experiments 3-8). Phosphorus uptake by leaves of different ages was also measured 16 and 60 minutes after (32)P addition to the medium (experiment 2).In experiment 1, treatments at 0.6 and 31 p.p.m. of phosphorus were applied when the first leaf had completed its rapid growth. The plants were then grown for three days in media labelled with (32)P, and for a subsequent 10 days in non-labelled solutions. Retranslocation was measured by changes in total phosphorus and in (32)P.Both root feeding, and foliar application of (32)P, demonstrated three phases during leaf development: import (recently initiated leaf), export (mature leaf) and an intermediate phase with both export and import (leaf half developed).There was large transport of foliar applied (32)P, from mature leaves to roots, and some of this (32)P was re-exported to the shoots, including the mature leaves. Root feeding of (32)P over short periods strongly suggested that phosphorus uptake by the shoots occurred via the xylem, even at low phosphorus.In experiment 1, there were distinct treatment differences in relative growth rates, growth of young organs and roots, and in phosphorus concentrations of all but the very young leaves. Mature leaves showed a large net phosphorus export at low phosphorus, but a large net import at high phosphorus. This was not due to treatment differences in export, because total export from the mature leaves was even somewhat smaller at low than at high phosphorus. The treatment differences, with net export at low but net import at high phosphorus, were thus due to the higher import in the mature leaves at high phosphorus. Total export remained at a high level throughout the experiment at high phosphorus, while it declined with time at low phosphorus.For phosphorus absorbed during early growth, both the export from the mature leaves, and the intake by the developing leaves, was independent of phosphorus treatment; i.e. for each individual organ the quantities of phosphorus involved were the same in the two phosphorus treatments. Thus, the higher phosphorus contents of developing organs at high phosphorus were obtained from phosphorus supplied to the roots during later growth, and not from phosphorus supplied during early growth of the whole plant.The data are consistent with the notion that phosphorus export is controlled in the source. It is suggested that at high phosphorus this control is due to a saturation of the sites transporting phosphorus into the phloem. At low phosphorus, on the other hand, release from individual leaf cells might have been the dominating factor. PMID:24553988

  18. [Effect of iron plaque on root surfaces on phosphorus uptake of two wetland plants].

    PubMed

    Wang, Zhen-yu; Liu, Li-hua; Wen, Sheng-fang; Peng, Chang-sheng; Xing, Bao-shan; Li, Feng-min

    2010-03-01

    In situ micro-suction cups were used to collect samples of soil solution with Arundo donax Linn and Typha latifolia from defined segments at rhizosphere in field. The experiment was conducted to elucidate the contribution of iron plaque while wetland plants were used to remove phosphorus. The reddish iron plaque was observed and measured on the surfaces of roots of Arundo donax Linn and Typha latifolia in the field, 20,170.8 mg/kg (fresh weight) for Arundo donax Linn and 7640.3 mg/kg (fresh weight) for Typha latifolia were collected. Olsen-P contents of Arundo donax Linn with iron plaque were 28.85 mg/kg, 46.2% more than that of without, 34.99 mg/kg for Typha latifolia 21.9% more than that of without. The phosphate concentrations in the in situ rhizosphere soil solution of Arundo donax Linn with iron plaque were 0.65 mg/kg, 9.2% more than that of without, 0.56 mg/kg for Typha latifolia, 33.9% more than that of without. The phosphorus contents adsorbed by iron plaque were 81.7% for Arundo donax Linn and 85.7% for Typha latifolia of the wetland plants with iron plaque. Phosphate use efficiency of Arundo donax Linn with iron plaque was 16.5% more than that of without, 31.4% for Typha latifolia. The contents of phosphorus of single plant of the two wetland plants with iron plaque are higher than that of without. Due to adsorb phosphate with iron plaque, the transfer speeds of phosphate from non-rhizosphere to rhizosphere and from soil to soil solution are increasing. The phosphorus contents with iron plaque accumulated at rhizosphere and depleted at rhizosphere without iron plaque of Arundo donax Linn and Typha latifolia. PMID:20358843

  19. [Phosphorus rhizosphere depletion effect of four aquatic plants].

    PubMed

    Wang, Zhen-yu; Wen, Sheng-fang; Xing, Bao-shan; Gao, Dong-mei; Li, Feng-min; Hu, Hong-ying; Sakoda, Akiyoshi; Sagehashi, Masaki

    2008-09-01

    Four aquatic plants (Alternanthera philoxeroides, Typha latifolia, Sagittaria sagittifolia, Phragmites communis ) were cultured on P-enriched soil in a pot experiment to assess the phosphorus rhizosphere depletion effect and analysis the ratio of root to shoot, root morphology, phosphorus uptake efficiency and phosphorus use efficiency. An obvious variation in P concentration of the soil in the rhizophere and non- rhizophere was observed. Compared with the non-rhizosphere (available P: 167.53 microg x g(-1)), the available P in the rhizosphere soil of Alternanthera philoxeroides, Typha latifolia, Sagittaria sagittifolia and Phragmites communis was reduced to 80.17, 124.37, 155.38 and 161.75 microg x g(-1) respectively, with 81%, 42%, 18% and 16% reduction ratio of water-soluble phosphorus. More effective phosphorus depletion was achieved in Alternanthera philoxeroides by higher phosphorus uptake efficiency (1.32 mg x m(-1)), while rooting system was small and phosphorus use efficiency was low (0.34 g x mg(-1)). Phosphorus uptake efficiency of Typha latjfolia is much lower (0.52 mg x m(-1)) than that of Alternanthera philoxeroides, however, its strong rooting system enhanced soil exploration, with higher phosphorus use efficiency (0.64 g x mg(-1)) and the ratio of root to shoot (0.35). Alternantshera philoxeroides and Typha latfolia were more effective in phosphorus depletion of the rhizosphere soil than that in Sagittaria sagittifolia and Phragmites communis. PMID:19068629

  20. Lightning-induced reduction of phosphorus oxidation state

    NASA Astrophysics Data System (ADS)

    Pasek, Matthew; Block, Kristin

    2009-08-01

    Phosphorus is frequently the limiting nutrient in marine and terrestrial ecosystems, largely owing to its poor solubility and slow movement through the rock cycle. Phosphorus is viewed to exist in geological systems almost exclusively in its fully oxidized state as orthophosphate. However, many microorganisms use the partially oxidized forms-phosphite and hypophosphite-as alternative phosphorus sources, and genomic evidence suggests that this selectivity is ancient. Elucidating the processes that reduce phosphate is therefore key to understanding the biological cycling of phosphorus. Here we show that cloud-to-ground lightning reduces phosphate in lightning-derived glass compounds, termed fulgurites. We analysed the phosphorus chemistry of ten fulgurites retrieved from North America, Africa and Australia, using microprobes and 31P nuclear magnetic resonance. Half of the fulgurites contained reduced phosphorus, mainly in the form of phosphite. The amount and type of reduced phosphorus was dependent on the composition of the fulgurite section examined: carbon-rich sections contained around 22% reduced phosphorus in the form of iron phosphide, whereas other fulgurites contained between 37 and 68% in the form of phosphite. We suggest that lightning provides some portion of the reduced phosphorus used by microbes, and that phosphate reduction by lightning can be locally important to phosphorus biogeochemistry.

  1. Soil studies using sweet vernal to assess element availability IV. Phosphorus

    Microsoft Academic Search

    N. Wells; W. M. H. Saunders

    1960-01-01

    The phosphorus status of New Zealand topsoils is surveyed in terms of total, organic, and inorganic phosphorus fractions, solubility of the inorganic phosphorus in N H2SO4 and phosphorus content of the grass, sweet vernal (Anthoxanthum odoratum). Use is made of the genetic soil classification to show how the plant and soil phosphorus values are influenced by the nature and degree

  2. In vitro PAMAM, phosphorus and viologen-phosphorus dendrimers prevent rotenone-induced cell damage.

    PubMed

    Milowska, Katarzyna; Szwed, Aleksandra; Zablocka, Maria; Caminade, Anne-Marie; Majoral, Jean-Pierre; Mignani, Serge; Gabryelak, Teresa; Bryszewska, Maria

    2014-10-20

    We have investigated whether polyamidoamine (PAMAM), phosphorus (pd) and viologen-phosphorus (vpd) dendrimers can prevent damage to embryonic mouse hippocampal cells (mHippoE-18) caused by rotenone, which is used as a pesticide, insecticide, and as a nonselective piscicide, that works by interfering with the electron transport chain in mitochondria. Several basic aspects, such as cell viability, production of reactive oxygen species and changes in mitochondrial transmembrane potential, were analyzed. mHippoE-18 cells were treated with these structurally different dendrimers at 0.1?M. A 1h incubation with dendrimers was followed by the addition of rotenone at 1?M, and a further 24h incubation. PAMAM, phosphorus and viologen-phosphorus dendrimers all increased cell viability (reduced cell death-data need to be compared with untreated controls). A lower level of reactive oxygen species and a favorable effect on mitochondrial system were found with PAMAM and viologen-phosphorus dendrimers. These results indicate reduced toxicity in the presence of dendrimers. PMID:25108046

  3. Black phosphorus field-effect transistors.

    PubMed

    Li, Likai; Yu, Yijun; Ye, Guo Jun; Ge, Qingqin; Ou, Xuedong; Wu, Hua; Feng, Donglai; Chen, Xian Hui; Zhang, Yuanbo

    2014-05-01

    Two-dimensional crystals have emerged as a class of materials that may impact future electronic technologies. Experimentally identifying and characterizing new functional two-dimensional materials is challenging, but also potentially rewarding. Here, we fabricate field-effect transistors based on few-layer black phosphorus crystals with thickness down to a few nanometres. Reliable transistor performance is achieved at room temperature in samples thinner than 7.5 nm, with drain current modulation on the order of 10(5) and well-developed current saturation in the I-V characteristics. The charge-carrier mobility is found to be thickness-dependent, with the highest values up to ? 1,000 cm(2) V(-1) s(-1) obtained for a thickness of ? 10 nm. Our results demonstrate the potential of black phosphorus thin crystals as a new two-dimensional material for applications in nanoelectronic devices. PMID:24584274

  4. Thermoelectric power of bulk black-phosphorus

    NASA Astrophysics Data System (ADS)

    Flores, E.; Ares, J. R.; Castellanos-Gomez, A.; Barawi, M.; Ferrer, I. J.; Sánchez, C.

    2015-01-01

    The potential of bulk black-phosphorus, a layered semiconducting material with a direct band gap of ˜0.3 eV, for thermoelectric applications has been experimentally studied. The Seebeck Coefficient (S) has been measured in the temperature range from 300 K to 385 K, finding a value of S = +335 ± 10 ?V/K at room temperature (indicating a naturally occurring p-type conductivity). S increases with temperature, as expected for p-type semiconductors, which can be attributed to an increase of the charge carrier density. The electrical resistance drops up to a 40% while heating in the studied temperature range. As a consequence, the power factor at 385 K is 2.7 times higher than that at room temperature. This work indicates the prospective use of black-phosphorus in thermoelectric applications such as thermal energy scavenging, which typically require devices with high performance at temperatures near room temperature.

  5. Soil Organic Phosphorus Speciation Using Spectroscopic Techniques

    Microsoft Academic Search

    Ashlea L. Doolette; Ronald J. Smernik

    \\u000a The most commonly used differentiation of soil phosphorus (P) is between inorganic and organic forms, despite the fact that\\u000a this is only the beginning of soil P speciation. Forms of inorganic and organic soil P include a large range of specific P\\u000a compounds, and spectroscopic techniques can offer the best potential for determining the speciation of soil organic P. The

  6. Phosphorus accumulation in Proteaceae seeds: a synthesis

    Microsoft Academic Search

    Philip K. Groom; Byron B. Lamont

    2010-01-01

    The family Proteaceae dominates the nutrient-poor, Mediterranean-climate floristic regions of southwestern Australia (SWA)\\u000a and the Cape of South Africa. It is well-recognised that mediterranean Proteaceae have comparatively large seeds that are\\u000a enriched with phosphorus (P), stored mainly as salts of phytic acid in protein globoids. Seed P can contribute up to 48% of\\u000a the total aboveground P, with the fraction

  7. Soil phosphorus dynamics: agronomic and environmental impacts

    Microsoft Academic Search

    Andrew N. Sharpley

    1995-01-01

    Phosphorus (P) related eutrophication of surface water is of increasing concern in many areas of the U.S. This concern has arisen where inputs of P in fertilizer and manure to agricultural systems have exceeded output in harvested crops for several years. As the loss of P in surface (r2 0.85 to 0.96) and subsurface drainage (r2 0.86) have been shown

  8. Redox chemistry in the phosphorus biogeochemical cycle.

    PubMed

    Pasek, Matthew A; Sampson, Jacqueline M; Atlas, Zachary

    2014-10-28

    The element phosphorus (P) controls growth in many ecosystems as the limiting nutrient, where it is broadly considered to reside as pentavalent P in phosphate minerals and organic esters. Exceptions to pentavalent P include phosphine--PH3--a trace atmospheric gas, and phosphite and hypophosphite, P anions that have been detected recently in lightning strikes, eutrophic lakes, geothermal springs, and termite hindguts. Reduced oxidation state P compounds include the phosphonates, characterized by C-P bonds, which bear up to 25% of total organic dissolved phosphorus. Reduced P compounds have been considered to be rare; however, the microbial ability to use reduced P compounds as sole P sources is ubiquitous. Here we show that between 10% and 20% of dissolved P bears a redox state of less than +5 in water samples from central Florida, on average, with some samples bearing almost as much reduced P as phosphate. If the quantity of reduced P observed in the water samples from Florida studied here is broadly characteristic of similar environments on the global scale, it accounts well for the concentration of atmospheric phosphine and provides a rationale for the ubiquity of phosphite utilization genes in nature. Phosphine is generated at a quantity consistent with thermodynamic equilibrium established by the disproportionation reaction of reduced P species. Comprising 10-20% of the total dissolved P inventory in Florida environments, reduced P compounds could hence be a critical part of the phosphorus biogeochemical cycle, and in turn may impact global carbon cycling and methanogenesis. PMID:25313061

  9. Redox chemistry in the phosphorus biogeochemical cycle

    PubMed Central

    Pasek, Matthew A.; Sampson, Jacqueline M.; Atlas, Zachary

    2014-01-01

    The element phosphorus (P) controls growth in many ecosystems as the limiting nutrient, where it is broadly considered to reside as pentavalent P in phosphate minerals and organic esters. Exceptions to pentavalent P include phosphine—PH3—a trace atmospheric gas, and phosphite and hypophosphite, P anions that have been detected recently in lightning strikes, eutrophic lakes, geothermal springs, and termite hindguts. Reduced oxidation state P compounds include the phosphonates, characterized by C?P bonds, which bear up to 25% of total organic dissolved phosphorus. Reduced P compounds have been considered to be rare; however, the microbial ability to use reduced P compounds as sole P sources is ubiquitous. Here we show that between 10% and 20% of dissolved P bears a redox state of less than +5 in water samples from central Florida, on average, with some samples bearing almost as much reduced P as phosphate. If the quantity of reduced P observed in the water samples from Florida studied here is broadly characteristic of similar environments on the global scale, it accounts well for the concentration of atmospheric phosphine and provides a rationale for the ubiquity of phosphite utilization genes in nature. Phosphine is generated at a quantity consistent with thermodynamic equilibrium established by the disproportionation reaction of reduced P species. Comprising 10–20% of the total dissolved P inventory in Florida environments, reduced P compounds could hence be a critical part of the phosphorus biogeochemical cycle, and in turn may impact global carbon cycling and methanogenesis. PMID:25313061

  10. Electronic Properties of Few-layer Black Phosphorus

    NASA Astrophysics Data System (ADS)

    Li, Likai; Yu, Yijun; Ye, G. J.; Chen, X. H.; Zhang, Yuanbo

    2013-03-01

    Black phosphorus is a layered allotropy of phosphorus that closely resembles graphite. In a single atomic layer, phosphorus atoms are covalently bonded into a puckered honey comb structure. All five valence electrons are localized, so unlike graphene monolayer black phosphorus is a semiconductor with a band gap of ˜ 2 eV. In a bulk crystal the interlayer coupling reduces the band gap to ˜ 0.3 eV. Using mechanical exfoliation method, we have successfully fabricated few layer black phosphorus field effect transistors. Our samples exhibit bipolar behavior with on-off ratio up to 10^6, and a low off-state current. Electronic mobilities up to ˜ 1000 cm^2V-1s-1 are currently achieved, with possibilities for further improvement. Such characteristics make black phosphorus a potential candidate for future nanoelectronic applications.

  11. Semiconducting black phosphorus: synthesis, transport properties and electronic applications.

    PubMed

    Liu, Han; Du, Yuchen; Deng, Yexin; Ye, Peide D

    2014-10-13

    Phosphorus is one of the most abundant elements preserved in earth, and it comprises a fraction of ?0.1% of the earth crust. In general, phosphorus has several allotropes, and the two most commonly seen allotropes, i.e. white and red phosphorus, are widely used in explosives and safety matches. In addition, black phosphorus, though rarely mentioned, is a layered semiconductor and has great potential in optical and electronic applications. Remarkably, this layered material can be reduced to one single atomic layer in the vertical direction owing to the van der Waals structure, and is known as phosphorene, in which the physical properties can be tremendously different from its bulk counterpart. In this review article, we trace back to the research history on black phosphorus of over 100 years from the synthesis to material properties, and extend the topic from black phosphorus to phosphorene. The physical and transport properties are highlighted for further applications in electronic and optoelectronics devices. PMID:25307017

  12. The atmospheric deposition of phosphorus in Lake Victoria (East Africa)

    Microsoft Academic Search

    Rashid A. Tamatamah; Robert E. Hecky; Hamish C. Duthie

    2005-01-01

    Wet and dry atmospheric fluxes of total phosphorus (TP) and soluble reactive phosphorus (SRP) measured at four sites over a 12-month period were used to estimate lake-wide atmospheric phosphorus (P) deposition to Lake Victoria, East Africa. Atmospheric samples were collected in plastic buckets with top diameter of 25.5 cm by 30 cm deep. The highest P loading rates of 2.7 (TP) and

  13. Phosphorus Purifing Effect of Blast Furnace Slags in Sewage

    Microsoft Academic Search

    Ling Huang; Haihong Xu

    2009-01-01

    The paper focus on purifying phosphorus by batch and column experiment and researching phosphorus removal theory of blast furnace slags. The content includes the following main parts: experiment method and procedure, results and discussion and conclusion. The results indicated: the phosphorus removal rate of solution containing 10 mg\\/L P is above 85% with 2.5 g BF slags, at 25°C. The

  14. Water quality criteria for white phosphorus: Final report. [Contains glossary

    SciTech Connect

    Davidson, K.A.; Hovatter, P.S.; Sigmon, C.F.

    1987-08-01

    Data obtained from a review of the literature concerning the environmental fate and aquatic and mammalian toxicity of white phosphorus are presented to derive Water Quality Criteria for the protection of humans and aquatic organisms and their uses. Laboratory and field studies indicate that white phosphorus is quite toxic to aquatic organisms, with fish being more sensitive than macroinvertebrates. Bioaccumulation is rapid and extensive, with the greatest uptake in the liver and muscle of fish and the hepatopancreas of lobster; however, depuration occurs within 7 days postexposure. Other toxic effects to aquatic organisms include cardiovascular and histological changes. Field studies indicate that effluents containing white phosphorus adversely affect receiving aquatic systems by decreasing diversity and increasing mortality of select species. Acute exposure to white phosphorus causes similar effects in laboratory animals and humans. In the absence of medical treatment, the estimated minimal lethal dose of white phosphorus in humans is 100 mg (1.4 mg/kg). Following ingestion, organs damaged by white phosphorus are the gastrointestinal tract, liver, kidney, brain, and cardiovascular system. Chronic and subchronic exposure of laboratory animals to white phosphorus by oral or subcutaneous routes results in reduced growth, reduced survival at high does, increased survival at low doses, and bone pathology. Humans chronically exposed to white phosphorus in the occupational environment develop a specific lesion (different from that observed in laboratory animals) called phosphorus necrosis of the jawbone or ''phossy jaw.'' 139 refs., 1 fig., 18 tabs.

  15. Method of removing and detoxifying a phosphorus-based substance

    DOEpatents

    Vandegrift, G.F.; Steindler, M.J.

    1985-05-21

    A method of removing a phosphorus-based poisonous substance from water contaminated is presented. In addition, the toxicity of the phosphorus-based substance is also subsequently destroyed. A water-immiscible organic solvent is first immobilized on a supported liquid membrane before the contaminated water is contacted with one side of the supported liquid membrane to absorb the phosphorus-based substance in the organic solvent. The other side of the supported liquid membrane is contacted with a hydroxy-affording strong base to react with phosphorus-based solvated species to form a non-toxic product.

  16. 21 CFR 862.1580 - Phosphorus (inorganic) test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1580 Phosphorus (inorganic) test system. (a)...

  17. 21 CFR 862.1580 - Phosphorus (inorganic) test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...urine. Measurements of phosphorus (inorganic) are used in the diagnosis and treatment of various disorders, including parathyroid gland and kidney diseases, and vitamin D imbalance. (b) Classification. Class...

  18. NMR and mass spectrometry of phosphorus in wetlands

    USGS Publications Warehouse

    El-Rifai, H.; Heerboth, M.; Gedris, T.E.; Newman, S.; Orem, W.; Cooper, W.T.

    2008-01-01

    There is at present little information on the long-term stability of phosphorus sequestered in wetlands. Phosphorus sequestered during high loading periods may be relatively unstable and easily remobilized following changes in nutrient status or hydrological regime, but the chemical forms of sequestered phosphorus that do remobilize are largely unknown at this time. A lack of suitable analytical techniques has contributed to this dearth of knowledge regarding the stability of soil organic phosphorus. We analysed phosphorus in soils from the 'head' of Rescue Strand tree island and an adjacent marsh in the Florida Everglades by 31P nuclear magnetic resonance (NMR) spectroscopy and high-resolution mass spectrometry. Tree islands are important areas of biodiversity within the Everglades and offer a unique opportunity to study phosphorus sequestration because they are exposed to large phosphorus loads and appear to be natural nutrient sinks. The 31P NMR profiling of extracts from surface and sediment samples in the tree island indicates that phosphorus input to Rescue Strand tree island soils is mostly in the form of inorganic ortho-phosphate and is either refractory when deposited or rapidly recycled by the native vegetation into a stable phosphorus pool largely resistant to re-utilization by plants or microbes. Mass spectrometry revealed the presence of inositol hexakisphosphate, a common organic monophosphate ester not previously observed in Everglades' soils. ?? 2008 The Authors.

  19. 75 FR 36306 - Chemical Mixtures Containing Listed Forms of Phosphorus and Change in Application Process

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-25

    ...Docket No. DEA-228P] RIN 1117-AA66 Chemical Mixtures Containing Listed Forms of Phosphorus...proposing regulations which establish those chemical mixtures containing red phosphorus...regulatory controls. DEA is proposing that chemical mixtures containing red phosphorus...

  20. 76 FR 31824 - Chemical Mixtures Containing Listed Forms of Phosphorus and Change in Application Process

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-02

    ...Docket No. DEA-228F] RIN 1117-AA66 Chemical Mixtures Containing Listed Forms of Phosphorus...proposed regulations which establish those chemical mixtures containing red phosphorus or...Substances Act (CSA) regulatory controls. Chemical mixtures containing red phosphorus...

  1. Ecological Engineering 14 (2000) 157167 Influence of chemical amendments on phosphorus

    E-print Network

    Florida, University of

    Ecological Engineering 14 (2000) 157­167 Influence of chemical amendments on phosphorus nutrients, especially phosphorus (P) are rapidly released upon flooding. The objective of this study: Alum; Flooding; Liming; Phosphorus release; Water quality; Wetland soils www

  2. The 14-MeV neutron activation analysis of Chinese medicines for protein, phosphorus, potassium and magnesium contents (II).

    PubMed

    Chuang, L S; Chiu, W Y

    1980-01-01

    Elementary form of nitrogen (protein), phosphorus, potassium and magnesium contained in 180 different kinds of Chinese medicines are analyzed by means of 14-MeV neutron activation technique. The percent contents of these elements in the Chinese medicines range from 0 to 34.41% (average: 11.73%) for protein, from 0.03 to 37.42% (average: 1.72%) for phosphorus, from 0.12 to 33.22% (average: 2.94%) for potassium and 0.03 to 5.62% (average: 0.43%) for magnesium. Comparison of the present results with the previous measurements for another 66 kinds of Chinese medicines is made. PMID:7395799

  3. Living donor liver transplantation for acute liver failure in pediatric patients caused by the ingestion of fireworks containing yellow phosphorus.

    PubMed

    Ates, Mustafa; Dirican, Abuzer; Ozgor, Dincer; Aydin, Cemalettin; Isik, Burak; Ara, Cengiz; Yilmaz, Mehmet; Ayse Selimoglu, M; Kayaalp, Cuneyt; Yilmaz, Sezai

    2011-11-01

    Yellow phosphorus is a protoplasmic toxicant that targets the liver. The ingestion of fireworks containing yellow phosphorus, either by children who accidentally consume them or by adults who are attempting suicide, often results in death due to acute liver failure (ALF). We present the outcomes of 10 children who ingested fireworks containing yellow phosphorus. There were 6 boys and 4 girls, and their ages ranged from 21 to 60 months. One patient remained stable without liver complications and was discharged. Three patients died of hepatorenal failure and cardiovascular collapse, and living donor liver transplantation (LDLT) was performed for 6 patients. The patients had grade II or III encephalopathy, a mean alanine aminotransferase level of 1148.2 IU/L, a mean aspartate aminotransferase level of 1437.5 IU/L, a mean total bilirubin level of 6.9 mg/dL, a mean international normalized ratio of 6.6, a mean Pediatric End-Stage Liver Disease score of 33.7, and a mean Child-Pugh score of 11.3. Postoperatively, 2 patients had persistent encephalopathy and died on the second or third postoperative day, and 1 patient died of cardiac arrest on the first postoperative day despite a well-functioning graft. The other 3 patients were still alive at a mean of 204 days. In conclusion, the ingestion of fireworks containing yellow phosphorus causes ALF with a high mortality rate. When signs of irreversible ALF are detected, emergency LDLT should be considered as a lifesaving procedure; however, if yellow phosphorus toxicity affects both the brain and the heart in addition to the liver, the mortality rate remains very high despite liver transplantation. PMID:21761550

  4. Surficial sediment phosphorus fractions along a biogeochemical gradient in Nyanza (Winam) Gulf, northeastern Lake Victoria and their possible role in phosphorus recycling and internal loading

    Microsoft Academic Search

    P. Gikuma-Njuru; R. E. Hecky; S. J. Guildford

    2010-01-01

    Different phosphorus fractions and metal element composition of surficial sediments were measured on three occasions in 2005\\u000a and 2006 along a transect between Nyanza Gulf and offshore Lake Victoria, in order to assess the potential for sediments to\\u000a contribute to the water column P concentrations in Lake Victoria. Total phosphorus (TP), apatite phosphorus (AP), inorganic\\u000a phosphorus (IP) and organic phosphorus

  5. [Modelling nitrogen and phosphorus transfer in Potamogeton malaianus Miq. decompostion].

    PubMed

    Han, Hong-Juan; Zhai, Shui-Jing; Hu, Wei-Ping

    2010-06-01

    Potamogeton malaianus Miq. is one of the dominant species of submerged aquatic vegetations in Lake Taihu, China. The decomposition of its debris and metabolic detritus is an important part of nutrients cycling in the lake water. Nitrogen and phosphorus transfer model in P. malaianus Miq. decomposition has been set up based on an indoor P. malaianus Miq. decomposition experiment to quantitatively characterize the decomposition process. It mainly focuses on the dissolving process of inorganic nitrogen and phosphorus in P. malaianus Miq., the degradation process of its organic nitrogen and phosphorus, and the boundary's adsorbing process of nitrogen and phosphorus in water. There are eight state variables in the model, including inorganic and organic nitrogen in P. malaianus Miq., inorganic and organic phosphorus in P. malaianus Miq., total nitrogen and total phosphorus in water, and nitrogen and phosphorus adsorbed on container boundary. The model calibration showed a good accordance with the observed results of P. malaianus Miq. decomposition experiment. The dissolve rates of inorganic nitrogen and phosphorus in P. malaianus Miq. are 0.04 d(-1) and 0.06 d(-1) respectively. And the decompose rates of these two state variables are 0.005 25 d(-1) and 0.010 44 d(-1) respectively. Model outputs show that 6.7% nitrogen and 35.8% phosphorus can release from P. malaianus Miq. in the former 5 days. Phosphorus release is prior to nitrogen due to the bigger inorganic/organic ratio of phosphorus than that of nitrogen in P. malaianus Miq., Decomposition of P. malaianus Miq. could be affected by water temperature, and the affection is slight when water temperature is lower according to the model. The model also showed that P. malaianus Miq. decomposition process has influences on water quality in the former days, which can be eliminated by adsorbing process later. PMID:20698260

  6. Estimating Phosphorus Loss in Runoff from Manure and Fertilizer for a Phosphorus Loss Quantification Tool

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Non-point source pollution of fresh waters by phosphorus (P) is a concern because it contributes to accelerated eutrophication. Qualitative P Indexes that estimate the risk of field-scale P loss have been developed in the USA and Europe. However, given the state of the science concerning agricultura...

  7. Influence of soil phosphorus and manure on phosphorus leaching in Swedish topsoils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In Sweden, subsurface transport of phosphorus (P) represents the primary pathway of concern to surface water quality. While strong relationships have been consistently observed between P in surface runoff and soil test P, there have been mixed findings linking P in leachate with soil test P. To expl...

  8. Phosphorus solubility of agricultural soils: a surface charge and phosphorus-31 NMR speciation study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We investigated ten soils from six states in United States to determine the relationship between potentiometric titration derived soil surface charge and Phosphorus-31 (P) nuclear magnetic resonance (NMR) speciation with the concentration of water-extractable P (WEP). The surface charge value at the...

  9. DEVELOPMENT OF A PHOSPHORUS INDEX FOR PASTURES FERTILIZED WITH POULTRY LITTER - FACTORS AFFECTING PHOSPHORUS RUNOFF.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Currently, several state and federal agencies are proposing upper limits on soil test phosphorus (P), above which animal manures can not be applied, based on the assumption that high P concentrations in runoff are due to high soil test P. Recent studies show that other factors are more indicative o...

  10. Effect of land application of phosphorus-saturated gypsum on soil phosphorus in a laboratory incubation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural drainage ditches can deliver high loads of phosphorus (P) to surface water. Installation of filter structures containing P sorbing materials (PSMs), including gypsum, is an emerging practice that has shown promise to reduce these P loads. The objective of this study was to evaluate what...

  11. Organic and inorganic sources of phosphorus on growth and phosphorus uptake in sorghum genotypes

    Microsoft Academic Search

    A. M. C. Furlani; R. B. Clark; J. W. Maranville; W. M. Ross

    1987-01-01

    Information about plant responses to different sources of phosphorus (P) is limited. Sorghum [Sorghum bicoior (L.) Moench] genotypes were grown with low levels of organic and inorganic sources of P in nutrient solution and soil to determine the availability of P from different P compounds and to note genotype differences for dry matter yield and P uptake. Plants grown in

  12. EVALUATION OF THE PHOSPHORUS SOURCE COMPONENT IN THE PHOSPHORUS INDEX FOR PASTURES.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Models that predict phosphorus (P) runoff from a variety of landscapes and farming systems are not widely available and are often difficult to use due to the large number of required input parameters. Therefore, a P index for pastures was developed to write nutrient management plans that determine ...

  13. MODIFICATION OF PHOSPHORUS EXPORT FROM A CATCHMENT BY FLUVIAL SEDIMENT PHOSPHORUS INPUTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) export from agricultural watersheds can accelerate freshwater eutrophication. Landscape-based remedial measures can reduce edge-of-field P losses. However stream channel hydraulics and fluvial sediment properties can modify the forms and amounts of P exported by the time it reaches th...

  14. Measuring Water-Extractable Phosphorus in Manures to Predict Phosphorus Concentrations in Runoff

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water-extractable phosphorus (WEP) in manures can influence the risk of P losses in runoff when manures are land applied. There is some uncertainty about how WEP in manures should be determined. Information on the effects of manure sample handling before analysis on WEP values and appropriate manu...

  15. SOIL PHOSPHORUS DISTRIBUTION AND CONCENTRATION FROM REPEATED STARTER PHOSPHORUS BAND APPLICATION

    Microsoft Academic Search

    John Stecker; James R. Brown

    2001-01-01

    Soil sampling to determine soil phosphorus (P) availability is complicated by the presence of residual P bands that have not been disturbed by tillage. This study investigated the soil P distribution and longevity of P bands applied in no-tillage culture on a Mollic Endoaqualf soil (fine, montmorillonitic, mesic). Starter band P treatments of 0, 5, 10, and 20 kg P

  16. Effect of Microwave Treatment Upon Processing Oolitic High Phosphorus Iron Ore for Phosphorus Removal

    NASA Astrophysics Data System (ADS)

    Tang, Hui-Qing; Liu, Wei-Di; Zhang, Huan-Yu; Guo, Zhan-Cheng

    2014-10-01

    Influence of microwave treatment on the previously proposed phosphorus removal process of oolitic high phosphorus iron ore (gaseous reduction followed by melting separation) has been studied. Microwave treatment was carried out using a high-temperature microwave reactor (Model: MS-WH). Untreated ore fines and microwaved ore fines were then characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and thermogravimetric analysis (TGA). Thereafter, experiments on the proposed phosphorus removal process were conducted to examine the effect of microwave treatment. Results show that microwave treatment could change the microstructure of the ore fines and has an intensification effect on its gaseous reduction by reducing gas internal resistance, increasing chemical reaction rate and postponing the occurrence of sintering. Results of gaseous reduction tests using tubular furnace indicate both microwave treatment and high reduction temperature high as 1273 K (1000 °C) are needed to totally break down the dense oolite and metallization rate of the ore fines treated using microwave power of 450 W could reach 90 pct under 1273 K (1000 °C) and for 2 hours. Results of melting separation tests of the reduced ore fines with a metallization rate of 90 pct show that, in addition to the melting conditions in our previous studies, introducing 3 pct Na2CO3 to the highly reduced ore fines is necessary, and metal recovery rate and phosphorus content of metal could reach 83 pct and 0.31 mass pct, respectively.

  17. Studies on phosphorus availability in poultry rations

    E-print Network

    Baruah, Jogendra Nath

    1959-01-01

    or mass of living bone. Schrarer and Schrarer (195^) used this method for bone density measurement in rats ? The cost prohibits use of the machine "under ordinary laboratory conditions. Anderson et al. (195&) developed a method for phosphorus avail..., 0.2 mg; Methionine,, 7500*0 mg; Glycine, 35OO.O mg; Niacin, 75*0 mg; Folic acid, 4.0 mg; Aureomycin HC1, 10.0 mg; Acconox (BHT 25$), 500*0 mg; Vitamin A, 10,000 I.U,; Vitamin B3, 2000 I.C.U.; ar-Toccopheryl acetate, 20 I.U.; Choline Chloride, 1...

  18. Enhanced biological phosphorus removal employing EDTA disodium

    SciTech Connect

    Bojinova, D.; Velkova, R. [Higher Inst. of Chemical Technology, Sofia (Bulgaria)

    1996-12-31

    The biological phosphorus removal is a promising alternative to the conventional chemical technologies for processing of phosphate raw materials. The object of this study was the effect of EDTA disodium on the biotreatment of tunisian phosphorite with the strain of Aspergillus niger. The incubation was carried out in two nutritive mediums, with different phosphate content. The experimental results showed that the additives of EDTA disodium in the nutritive medium increased the rate of extraction of P{sub 2}O{sub 5} and shortened significantly the time for biological leaching. 5 refs., 3 figs., 2 tabs.

  19. Assessing the Long Term Impact of Phosphorus Fertilization on Phosphorus Loadings Using AnnAGNPS

    PubMed Central

    Yuan, Yongping; Bingner, Ronald L.; Locke, Martin A.; Stafford, Jim; Theurer, Fred D.

    2011-01-01

    High phosphorus (P) loss from agricultural fields has been an environmental concern because of potential water quality problems in streams and lakes. To better understand the process of P loss and evaluate the effects of different phosphorus fertilization rates on phosphorus losses, the USDA Annualized AGricultural Non-Point Source (AnnAGNPS) pollutant loading model was applied to the Ohio Upper Auglaize watershed, located in the southern portion of the Maumee River Basin. In this study, the AnnAGNPS model was calibrated using USGS monitored data; and then the effects of different phosphorus fertilization rates on phosphorus loadings were assessed. It was found that P loadings increase as fertilization rate increases, and long term higher P application would lead to much higher P loadings to the watershed outlet. The P loadings to the watershed outlet have a dramatic change after some time with higher P application rate. This dramatic change of P loading to the watershed outlet indicates that a “critical point” may exist in the soil at which soil P loss to water changes dramatically. Simulations with different initial soil P contents showed that the higher the initial soil P content is, the less time it takes to reach the “critical point” where P loadings to the watershed outlet increases dramatically. More research needs to be done to understand the processes involved in the transfer of P between the various stable, active and labile states in the soil to ensure that the model simulations are accurate. This finding may be useful in setting up future P application and management guidelines. PMID:21776225

  20. THE FATE AND TRANSPORT OF PHOSPHORUS IN AGRICULTURAL SYSTEMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) is an important input for economic crop and livestock production systems but excessive P losses from agricultural sources can accelerate eutrophication of surface waters. Phosphorus losses occur in particulate forms with eroded surface soil and in soluble forms in runoff and in some ...

  1. Phosphorus recovery from pig manure solids prior to land application

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Land disposal of pig manure is an environmental concern due to an imbalance of the nitrogen to phosphorus (N:P) ratio for crop production, leading to excess phosphorus (P) in soils and potential risks of water pollution. A process called “quick wash” was investigated for its feasibility to extract ...

  2. Soil derived phosphorus in surface runoff from grazed grassland lysimeters

    Microsoft Academic Search

    P. M. Haygarth; S. C. Jarvis

    1997-01-01

    Seven 1 ha grazed lysimeter plots, managed as intensive grassland for the last 12 years, were monitored for total phosphorus (TP) and molybdate reactive phosphorus (MRP) in surface runoff plus interflow to 30 cm depth, for up to ten events during 1994. The mean MRP and TP concentrations determined were 40 and 122 ?g 1?1, respectively, but the data were

  3. Removing phosphorus from sewage effluent and agricultural runoff

    E-print Network

    Heal, Kate

    321 14 Removing phosphorus from sewage effluent and agricultural runoff using recovered ochre K, for instance,Younger et al., 2002). Typically, this ochre is stockpiled pending use or disposal. Although sewage effluent and agricultural runoff. Phosphorus pollution from point and diffuse sources is a serious

  4. 46 CFR 151.50-50 - Elemental phosphorus in water.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...Elemental phosphorus in water. 151.50-50 ...BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements...Elemental phosphorus in water. (a) Tanks shall...then cooled until the water above the cargo has a...presentation of satisfactory proof that procedures...

  5. 46 CFR 151.50-50 - Elemental phosphorus in water.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...Elemental phosphorus in water. 151.50-50 ...BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements...Elemental phosphorus in water. (a) Tanks shall...then cooled until the water above the cargo has a...presentation of satisfactory proof that procedures...

  6. REMOVAL OF HEAVY METALS USING ALUMINUM SALTS FOR PHOSPHORUS REMOVAL

    EPA Science Inventory

    The use of aluminum salts to remove phosphorus is common practice. It has been shown that aluminum salts are also capable of removing heavy metals, but the dosages were much greater than normally applied for phosphorus removal. This study investigates the removal of heavy metals ...

  7. Solubility of manure phosphorus characterized by selective and sequential extractions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The increasing awareness of the severity of the problem of phosphorus (P) derived from agricultural production moving off-farm and threatening water quality has led to the search for methods to characterize the forms and potential solubilities of phosphorus in food animal manures and manure products...

  8. The influence of animals on phosphorus cycling in lake ecosystems

    Microsoft Academic Search

    Gunnar Andersson; Wilhelm Granéli; Jan Stenson

    1988-01-01

    Aquatic animals directly influence the cycling of phosphorus in lakes through feeding and excretion. Traditionally, animals (zooplankton, benthic invertebrates and fish) have been assigned only minor roles in the process of freshwater phosphorus cycling. They were regarded as consumers without much regulating influence. Today there is growing evidence that animals, predators and herbivores, directly or indirectly can control biomass of

  9. Mapping and cloning of low phosphorus tolerance genes in soybeans.

    PubMed

    Dan, Zhang; Haina, Song; Hao, Cheng; Deyue, Yu

    2015-04-20

    Soybean is a major source of edible oil and phytoprotein. Low phosphorus available in soil is an important factor limiting the current soybean production. Effective ways to solve the problem include identification of germplasms and genes tolerant to low-phosphorus stress, and cultivation of soybean varieties with high phosphorus efficiency. Recently many researches have been carrying out investigations to map and clone genes related to phosphorus efficiency in soybeans. However, due to the complexity of the soybean genome and little knowledge of functional genes, it has been difficult to understand the mechanism of soybean tolerance to low phosphorus. Although quantitative trait locus (QTL) mapping related to low phosphorus tolerance has made some progress, it remains elusive to obtain accurate candidate genes for molecular breeding applications, due to the limited accuracy of QTL. Even for the cloned soybean low phosphorus tolerance genes, the molecular mechanisms are largely unknown, further limiting the application to breeding. In this review, we summarize the progresses on mapping, cloning and functional characterization of soybean low phosphorus tolerance genes. PMID:25881699

  10. The chemistry of phosphorus in dense interstellar clouds

    NASA Technical Reports Server (NTRS)

    Thorne, L. R.; Anicich, V. G.; Prasad, S. S.; Huntress, W. T., Jr.

    1984-01-01

    Laboratory experiments show that the ion-molecule chemistry of phosphorus is significantly different from that of nitrogen in dense interstellar clouds. The PH3 molecule is not readily formed by gas-phase, ion-molecule reactions in these regions. Laboratory results used in a simple kinetic model indicate that the most abundant molecule containing phosphorus in dense clouds is PO.

  11. Soil phosphorus availability differences between sprinkler and furrow irrigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water flowing in irrigation furrows detaches and transports soil particles and subsequently nutrients such as phosphorus. To reduce the risk of erosion and offsite phosphorus transport, producers in south-central Idaho have been converting from furrow to sprinkler irrigation. We completed research...

  12. Electron impact ionization cross sections of phosphorus and arsenic molecules

    E-print Network

    Paris-Sud XI, Université de

    77 Electron impact ionization cross sections of phosphorus and arsenic molecules G. Monnom, Ph'ionisation dissociative obtenues par bombardement électronique des molécules d'arsenic As4 et As2 et de phosphore P4 et P2 ionization total cross sections of arsenic As4 and As2 molecules and phosphorus P4 and P2 molecules

  13. AMERICAN SOCIETY OF AGRONOMY BOOK "PHOSPHORUS, AGRICULTURE AND THE ENVIRONMENT"

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus: Agriculture and the Environment” provides a comprehensive, systematic review of the varied aspects of phosphorus (P) use in crop and livestock production and of the relationship between agricultural P management and water quality. This monograph draws upon the expertise of leading inte...

  14. Validation of a quantitative phosphorus loss assessment tool

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pasture Phosphorus Management Plus (PPM Plus) is a tool that allows nutrient management and conservation planners to evaluate phosphorus loss from agricultural fields. This tool is a modified version of the widely used Soil and Water Assessment Tool (SWAT) model with a vastly simplified interface. ...

  15. 76 FR 38592 - Phosphorus Water Quality Standards for Florida Everglades

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-01

    ...EPA-HQ-OW-2011-0515; FRL-9428-3] Phosphorus Water Quality Standards for Florida Everglades...would identify provisions of Florida's Water Quality Standards for Phosphorus in the...disapproved and that therefore are not applicable water quality standards for purposes of the...

  16. 77 FR 46298 - Phosphorus Water Quality Standards for Florida Everglades

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-03

    ...FRL 9666-8] RIN 2040-AF38 Phosphorus Water Quality Standards for Florida Everglades...that identifies provisions of Florida's Water Quality Standards for Phosphorus in the...disapproved and that therefore are not applicable water quality standards for purposes of the...

  17. Phosphorus Removal Characteristics in Hydroxyapatite Crystallization Using Converter Slag

    Microsoft Academic Search

    EUNG-HO KIM; HWAN-KOOK HWANG; SOO-BIN YIM

    2006-01-01

    This study was performed to investigate the phosphorus removal characteristics in hydroxyapatite (HAP) crystallization using converter slag as a seed crystal and the usefulness of a slag column reactor system. The effects of alkalinity, and the isomorphic-substitutable presence of ionic magnesium, fluoride, and iron on HAP crystallization seeded with converter slag, were examined using a batch reactor system. The phosphorus

  18. Estimating soil phosphorus sorption saturation from Mehlich-3 data

    Microsoft Academic Search

    Peter J. A. Kleinman; Andrew N. Sharpley

    2002-01-01

    Soil phosphorus sorption saturation (Psat) measures the degree to which soil phosphorus (P) sorption sites have been filled and has been found to be a good indicator of P availability to runoff and leachate. At present, analytical methods required to estimate Psat are generally not offered by soil testing laboratories. This study evaluated the use of Mehlich-3 data in estimating

  19. Do invasive mussels restrict offshore phosphorus transport in Lake Huron?

    PubMed

    Cha, Yoonkyung; Stow, Craig A; Nalepa, Thomas F; Reckhow, Kenneth H

    2011-09-01

    Dreissenid mussels were first documented in the Laurentian Great Lakes in the late 1980s. Zebra mussels (Dreissena polymorpha) spread quickly into shallow, hard-substrate areas; quagga mussels (Dreissena rostriformis bugensis) spread more slowly and are currently colonizing deep, offshore areas. These mussels occur at high densities, filter large water volumes while feeding on suspended materials, and deposit particulate waste on the lake bottom. This filtering activity has been hypothesized to sequester tributary phosphorus in nearshore regions reducing offshore primary productivity. We used a mass balance model to estimate the phosphorus sedimentation rate in Saginaw Bay, a shallow embayment of Lake Huron, before and after the mussel invasion. Our results indicate that the proportion of tributary phosphorus retained in Saginaw Bay increased from approximately 46-70% when dreissenids appeared, reducing phosphorus export to the main body of Lake Huron. The combined effects of increased phosphorus retention and decreased phosphorus loading have caused an approximate 60% decrease in phosphorus export from Saginaw Bay to Lake Huron. Our results support the hypothesis that the ongoing decline of preyfish and secondary producers including diporeia (Diporeia spp.) in Lake Huron is a bottom-up phenomenon associated with decreased phosphorus availability in the offshore to support primary production. PMID:21812427

  20. Managing phosphorus for water quality protection - 10 principles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The accelerated eutrophication of aquatic systems has primarily been the concern of developed nations where it represents the most pervasive impairment of surface water bodies. Managing phosphorus for water quality protection requires prudent tempering of agronomic emphases to build soil phosphorus,...

  1. The microbiology of biological phosphorus removal in activated sludge systems

    Microsoft Academic Search

    Robert J Seviour; Takashi Mino; Motoharu Onuki

    2003-01-01

    Activated sludge systems are designed and operated globally to remove phosphorus microbiologically, a process called enhanced biological phosphorus removal (EBPR). Yet little is still known about the ecology of EBPR processes, the microbes involved, their functions there and the possible reasons why they often perform unreliably. The application of rRNA-based methods to analyze EBPR community structure has changed dramatically our

  2. White lupin utilizes soil phosphorus that is unavailable to soybean

    Microsoft Academic Search

    S. M. Braum; P. A. Helmke

    1995-01-01

    White lupin (Lupinus albus L. var. Ultra) and soybean (Glycine max L. var. Elgin) were grown in an acidic soil low an available phosphorus (P) to investigate their different capacities to acquire soil phosphorus. Experiments done in the controlled environment of a biotron were supplemented with four separate greenhouse experiments. Lupin and soybean were grown in monoculture and intercropped on

  3. Africa Phosphorus Fertilizer Application Global Fertilizer and Manure, Version 1

    E-print Network

    Columbia University

    Africa Phosphorus Fertilizer Application Global Fertilizer and Manure, Version 1 Amount of phosphorus fertilizer applied averaged over all crops within the 0.5 deg grid cell. Grid cell values Fertilizer Application and Manure Production. Data distributed by the NASA Socioeconomic Data

  4. Phosphorus Removal in Sewage by Mixed Steel Slag Fillings

    Microsoft Academic Search

    Huang Ling; Su Yongqiang

    2009-01-01

    The purpose of the paper is purifying phosphorus by column experiment and researching phosphorus removal theory of substrates including steel slag, natural sand and limestone. The winch is composed of the following main parts: experiment method and procedure, results and discussion and conclusion. The results indicated: Pure steel slag is not suitable as filling in wastewater land treating. Mixing natural

  5. Approaches and Challenges to Engineering Seed Phytate and Total Phosphorus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    About 75% of seed total phosphorus (P) is found in a single compound, phytic acid (myo-inositol-1,2,3,4,5,6-hexakisphosphate or InsP6). Phytic acid is not efficiently utilized by monogastric animals (poultry, swine, fish), which creates phosphorus management and environmental impact problems in anim...

  6. Rearing temperature is inconsequential to broiler phosphorus excretion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A feeding trial was conducted to determine the influence of rearing temperature on phosphorus (P) excretion in male broilers. Experimental diets were formulated with three levels of dietary available phosphorus (aP): control at 0.38% aP, control less 20% or 0.304% aP, and control plus 20% or 0.456% ...

  7. THE PENNSYLVANIA PHOSPHORUS INDEX: INTEGRATING FARM MANAGEMENT OPTIONS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Pennsylvania Phosphorus Index: Version 1 has been selected by the Pennsylvania US Department of Agriculture-Natural Resource Conservation Service (USDA-NRCS) to address phosphorus management as a part of the agency’s 590 Nutrient Management Practice Standard. This standard provides guidance to ...

  8. Low Phytic Acid Barley Responses to Phosphorus Rates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Low phytic acid (LPA) barley (Hordeum vulgare L.) cultivars partition phosphorus in seed tissue differently than conventional barley cultivars through a reduction in seed phytic acid (myo-inositol-1,2,3,4,5,6-hexkisphosphate) coupled with an increase in inorganic phosphorus. The response of the LPA...

  9. Phosphorus retranslocation in Hordeum vulgare during early tillering

    Microsoft Academic Search

    H. Greenway; A. Gunn

    1966-01-01

    In Hordeum vulgare, phosphorus retranslocation was studied after it had been supplied to the roots for three days (experiment 1), and after foliar application (experiments 3–8). Phosphorus uptake by leaves of different ages was also measured 16 and 60 minutes after 32P addition to the medium (experiment 2).

  10. QUANTITATIVE DETERMINATION OF PHYTATE AND AVAILABLE PHOSPHORUS FOR MAIZE BREEDING

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phytate is the dominant storage form of phosphorus (P) in mature cereal and oil grains. Phosphorus bound in phytate is nutritionally unavailable to monogastric animals and thus contributes to water pollution because it is excreted in the manure. Also, phytate can chelate certain minerals and exace...

  11. Black phosphorus nanoelectromechanical resonators vibrating at very high frequencies.

    PubMed

    Wang, Zenghui; Jia, Hao; Zheng, Xuqian; Yang, Rui; Wang, Zefang; Ye, G J; Chen, X H; Shan, Jie; Feng, Philip X-L

    2015-01-21

    We report on the experimental demonstration of a new type of nanoelectromechanical resonator based on black phosphorus crystals. Facilitated by a highly efficient dry transfer technique, crystalline black phosphorus flakes are harnessed to enable drumhead resonators vibrating at high and very high frequencies (HF and VHF bands, up to ?100 MHz). We investigate the resonant vibrational responses from the black phosphorus crystals by devising both electrical and optical excitation schemes, in addition to measuring the undriven thermomechanical motions in these suspended nanostructures. Flakes with thicknesses from ?200 nm down to ?20 nm clearly exhibit elastic characteristics transitioning from the plate to the membrane regime. Both frequency- and time-domain measurements of the nanomechanical resonances show that very thin black phosphorus crystals hold interesting potential for moveable and vibratory devices and for semiconductor transducers where high-speed mechanical motions could be coupled to the attractive electronic and optoelectronic properties of black phosphorus. PMID:25385657

  12. Transport properties of ultrathin black phosphorus on hexagonal boron nitride

    NASA Astrophysics Data System (ADS)

    Doganov, Rostislav A.; Koenig, Steven P.; Yeo, Yuting; Watanabe, Kenji; Taniguchi, Takashi; Ã-zyilmaz, Barbaros

    2015-02-01

    Ultrathin black phosphorus, or phosphorene, is a two-dimensional material that allows both high carrier mobility and large on/off ratios. Similar to other atomic crystals, like graphene or layered transition metal dichalcogenides, the transport behavior of few-layer black phosphorus is expected to be affected by the underlying substrate. The properties of black phosphorus have so far been studied on the widely utilized SiO2 substrate. Here, we characterize few-layer black phosphorus field effect transistors on hexagonal boron nitride—an atomically smooth and charge trap-free substrate. We measure the temperature dependence of the field effect mobility for both holes and electrons and explain the observed behavior in terms of charged impurity limited transport. We find that in-situ vacuum annealing at 400 K removes the p-doping of few-layer black phosphorus on both boron nitride and SiO2 substrates and reduces the hysteresis at room temperature.

  13. Production of fluid fertilizer from phosphorus furnace waste stream

    SciTech Connect

    Barber, J. C.

    1985-04-30

    Processes and compositions of matter are disclosed for the production of liquid fertilizers wherein wastewater from a phosphorus smelting furnace is incorporated in liquid fertilizer processes. The wastewater replaces water evaporated and the wastewater dissolves fertilizer salts. A serious water pollution problem is avoided when wastewater is incorporated in liquid fertilizers. The invention discloses a process for making orthophosphate suspension fertilizer wherein impure phosphoric acid is neutralized in the condensing system, water from the condensing system is bled off, and a suspending clay is added to produce orthophosphate suspension fertilizer. In this process, phosphorus sludge made at phosphorus furnaces is used to produce suspension fertilizer, and wastewater from phosphate smelting furnaces is recovered. New compositions of matter are disclosed. A process is disclosed for making phosphoric acid with low impurities content wherein phosphorus sludge is burned to make impure orthophosphoric acid and the impure acid is recycled to an agglomerating step in a process for making elemental phosphorus.

  14. Improving Phosphorus Availability in an Acid Soil Using Organic Amendments Produced from Agroindustrial Wastes

    PubMed Central

    Ch'ng, Huck Ywih; Ahmed, Osumanu Haruna; Majid, Nik Muhamad Ab.

    2014-01-01

    In acid soils, soluble inorganic phosphorus is fixed by aluminium and iron. To overcome this problem, acid soils are limed to fix aluminium and iron but this practice is not economical. The practice is also not environmentally friendly. This study was conducted to improve phosphorus availability using organic amendments (biochar and compost produced from chicken litter and pineapple leaves, resp.) to fix aluminium and iron instead of phosphorus. Amending soil with biochar or compost or a mixture of biochar and compost increased total phosphorus, available phosphorus, inorganic phosphorus fractions (soluble inorganic phosphorus, aluminium bound inorganic phosphorus, iron bound inorganic phosphorus, redundant soluble inorganic phosphorus, and calcium bound phosphorus), and organic phosphorus. This was possible because the organic amendments increased soil pH and reduced exchangeable acidity, exchangeable aluminium, and exchangeable iron. The findings suggest that the organic amendments altered soil chemical properties in a way that enhanced the availability of phosphorus in this study. The amendments effectively fixed aluminium and iron instead of phosphorus, thus rendering phosphorus available by keeping the inorganic phosphorus in a bioavailable labile phosphorus pool for a longer period compared with application of Triple Superphosphate without organic amendments. PMID:25032229

  15. The Prevalence of Phosphorus Containing Food Additives in Top Selling Foods in Grocery Stores

    PubMed Central

    León, Janeen B.; Sullivan, Catherine M.; Sehgal, Ashwini R.

    2013-01-01

    Objective To determine the prevalence of phosphorus-containing food additives in best selling processed grocery products and to compare the phosphorus content of a subset of top selling foods with and without phosphorus additives. Design The labels of 2394 best selling branded grocery products in northeast Ohio were reviewed for phosphorus additives. The top 5 best selling products containing phosphorus additives from each food category were matched with similar products without phosphorus additives and analyzed for phosphorus content. Four days of sample meals consisting of foods with and without phosphorus additives were created and daily phosphorus and pricing differentials were computed. Setting Northeast Ohio Main outcome measures Presence of phosphorus-containing food additives, phosphorus content Results 44% of the best selling grocery items contained phosphorus additives. The additives were particularly common in prepared frozen foods (72%), dry food mixes (70%), packaged meat (65%), bread & baked goods (57%), soup (54%), and yogurt (51%) categories. Phosphorus additive containing foods averaged 67 mg phosphorus/100 gm more than matched non-additive containing foods (p=.03). Sample meals comprised mostly of phosphorus additive-containing foods had 736 mg more phosphorus per day compared to meals consisting of only additive-free foods. Phosphorus additive-free meals cost an average of $2.00 more per day. Conclusion Phosphorus additives are common in best selling processed groceries and contribute significantly to their phosphorus content. Moreover, phosphorus additive foods are less costly than phosphorus additive-free foods. As a result, persons with chronic kidney disease may purchase these popular low-cost groceries and unknowingly increase their intake of highly bioavailable phosphorus. PMID:23402914

  16. DECREASED ABSORPTION OF CALCIUM, MAGNESIUM, ZINC AND PHOSPHORUS BY HUMANS DUE TO INCREASED FIBER AND PHOSPHORUS CONSUMPTION AS WHEAT BREAD

    Microsoft Academic Search

    John G. Reinhold; Bahram Faradji; Parichehr Abadi; Faramarz Ismail-Beigi

    2009-01-01

    During a 20 day period of high fiber consumption in the form of bread made partly from wheaten wholemeal, two men developed negative balances of calcium, magnesium, zinc and phosphorus due to in creased fecal excretion of each element. The fecal losses correlated closely with fecal dry matter and phosphorus. Fecal dry matter, in turn, was directly proportional to fecal

  17. DISTRIBUTED HYDROLOGICAL MODELING OF TOTAL DISSOLVED PHOSPHORUS TRANSPORT IN AN AGRICULTURAL LANDSCAPE. PART II: DISSOLVED PHOSPHORUS TRANSPORT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reducing non-point source phosphorus (P) loss to drinking water reservoirs is a main concern for New York City watershed planners, and modeling of P transport can assist in the evaluation of agricultural effects on nutrient dynamics. A spatially distributed model of total dissolved phosphorus (TDP) ...

  18. Formation of stable phosphorus-carbon bond for enhanced performance in black phosphorus nanoparticle-graphite composite battery anodes.

    PubMed

    Sun, Jie; Zheng, Guangyuan; Lee, Hyun-Wook; Liu, Nian; Wang, Haotian; Yao, Hongbin; Yang, Wensheng; Cui, Yi

    2014-08-13

    High specific capacity battery electrode materials have attracted great research attention. Phosphorus as a low-cost abundant material has a high theoretical specific capacity of 2596 mAh/g with most of its capacity at the discharge potential range of 0.4-1.2 V, suitable as anodes. Although numerous research progress have shown other high capacity anodes such as Si, Ge, Sn, and SnO2, there are only a few studies on phosphorus anodes despite its high theoretical capacity. Successful applications of phosphorus anodes have been impeded by rapid capacity fading, mainly caused by large volume change (around 300%) upon lithiation and thus loss of electrical contact. Using the conducting allotrope of phosphorus, "black phosphorus" as starting materials, here we fabricated composites of black phosphorus nanoparticle-graphite by mechanochemical reaction in a high energy mechanical milling process. This process produces phosphorus-carbon bonds, which are stable during lithium insertion/extraction, maintaining excellent electrical connection between phosphorus and carbon. We demonstrated high initial discharge capacity of 2786 mAh·g(-1) at 0.2 C and an excellent cycle life of 100 cycles with 80% capacity retention. High specific discharge capacities are maintained at fast C rates (2270, 1750, 1500, and 1240 mAh·g(-1) at C/5, 1, 2, and 4.5 C, respectively). PMID:25019417

  19. DEVELOPMENT OF REGIONALLY-CONSISTENT PHOSPHORUS SOURCE COEFFICIENTS FOR USE IN PHOSPHORUS INDEX EVALUATIONS IN THE MID-ATLANTIC REGION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Phosphorus Index was designed as a screening tool for use by soil conservation field staff and nutrient management planners to rank the relative vulnerability of agricultural fields as sources of phosphorus (P) loss to surface waters. Development of individual P Indices in the Mid-Atlantic Regi...

  20. Atmospheric phosphorus in the northern part of Lake Taihu, China.

    PubMed

    Luo, Jun; Wang, Xiaorong; Yang, Hong; Yu, Jian Zhen; Yang, Longyuan; Qin, Boqiang

    2011-08-01

    Eutrophication, which has been linked to enhanced nutrient loading in lakes, estuarine and coastal waters, is common to many water bodies in China, including Lake Taihu. The atmosphere is an important and growing source of new nutrients entering water bodies. To assess the impact of atmospheric phosphorus (P) on water quality of Lake Taihu, we have estimated the atmospheric input of P by measuring its concentrations in aerosols and in rainwater. Samples were collected at the northeastern part of the lake. The P concentration in total suspended particle ranged from 0.054 to 0.300 ?g m(-3). Concentrations of P in aerosols in the winter and autumn samples were higher than those in the spring and summer samples. Soluble inorganic P (SIP), which provides direct nutrient sources to algae, accounts for 4.9%-83.4% of the total P. Principal Component Analysis of the measured aerosol constituents and examination of inter-species correlation indicate that SIP was correlated with elemental carbon, water soluble organic carbon, NO(3)(-), and Ca(2+). Such correlations could be explained if two nearby coal-fired power plants were a major aerosol P sources. The average concentration of the total P in rain water samples was 0.082±0.058 mg P/L. The annual deposition flux of P into the northern part of Lake Taihu was estimated to be in the range of 0.04-0.44 kg ha(-1)year(-1) through dry deposition and 0.33 kg ha(-1)year(-1) through wet deposition. The combined wet and dry deposition was less than 8% of riverine P input, therefore the atmospheric deposition was only a minor contributor to P in Lake Taihu at the time of this study. PMID:21339003

  1. Black Phosphorus Radio-Frequency Transistors

    NASA Astrophysics Data System (ADS)

    Wang, Han; Wang, Xiaomu; Xia, Fengnian; Wang, Luhao; Jiang, Hao; Xia, Qiangfei; Chin, Matthew L.; Dubey, Madan; Han, Shu-jen

    2014-11-01

    Few-layer and thin film forms of layered black phosphorus (BP) have recently emerged as a promising material for applications in high performance nanoelectronics and infrared optoelectronics. Layered BP thin film offers a moderate bandgap of around 0.3 eV and high carrier mobility, leading to transistors with decent on-off ratio and high on-state current density. Here, we demonstrate the gigahertz frequency operation of black phosphorus field-effect transistors for the first time. The BP transistors demonstrated here show excellent current saturation with an on-off ratio exceeding 2000. We achieved a current density in excess of 270 mA/mm and DC transconductance above 180 mS/mm for hole conduction. Using standard high frequency characterization techniques, we measured a short-circuit current-gain cut-off frequency fT of 12 GHz and a maximum oscillation frequency fmax of 20 GHz in 300 nm channel length devices. BP devices may offer advantages over graphene transistors for high frequency electronics in terms of voltage and power gain due to the good current saturation properties arising from their finite bandgap, thus enabling the future ubiquitous transistor technology that can operate in the multi-GHz frequency range and beyond.

  2. 33 CFR 83.33 - Equipment for sound signals (Rule 33).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Equipment for sound signals (Rule 33). 83.33 Section 83...SECURITY INLAND NAVIGATION RULES RULES Sound and Light Signals § 83.33 Equipment for sound signals (Rule 33). (a) Vessels of...

  3. 33 CFR 83.33 - Equipment for sound signals (Rule 33).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Equipment for sound signals (Rule 33). 83.33 Section 83...SECURITY INLAND NAVIGATION RULES RULES Sound and Light Signals § 83.33 Equipment for sound signals (Rule 33). (a) Vessels of...

  4. 33 CFR 83.33 - Equipment for sound signals (Rule 33).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Equipment for sound signals (Rule 33). 83.33 Section 83...SECURITY INLAND NAVIGATION RULES RULES Sound and Light Signals § 83.33 Equipment for sound signals (Rule 33). (a) Vessels of...

  5. 33 CFR 83.33 - Equipment for sound signals (Rule 33).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Equipment for sound signals (Rule 33). 83.33 Section 83...SECURITY INLAND NAVIGATION RULES RULES Sound and Light Signals § 83.33 Equipment for sound signals (Rule 33). (a) Vessels of...

  6. 33 CFR 83.33 - Equipment for sound signals (Rule 33).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Equipment for sound signals (Rule 33). 83.33 Section 83...SECURITY INLAND NAVIGATION RULES RULES Sound and Light Signals § 83.33 Equipment for sound signals (Rule 33). (a) Vessels of...

  7. Estimation of Nitrogen and Phosphorus in Effluent from the Striped Catfish Farming Sector in the Mekong Delta, Vietnam

    Microsoft Academic Search

    Sena S. De Silva; Brett A. Ingram; Phuong T. Nguyen; Tam M. Bui; Geoff J. Gooley; Giovanni M. Turchini

    2010-01-01

    In this study an attempt is made to estimate nitrogen and phosphorus discharged to the environment from the striped catfish\\u000a (Pangasianodon hypophthalmus) farming sector in the Mekong Delta (8°33?–10°55?N, 104°30?–106°50?E), South Vietnam. The sector accounted for 687,000 t\\u000a production in 2007 and 1,094,879 t in 2008, with over 95% of the produce destined for export to over 100 countries. Commercial\\u000a and farm-made

  8. X-ray photoelectron spectroscopy and nuclear magnetic resonance structural study of phosphorus oxynitride glasses, ‘LiNaPON’

    Microsoft Academic Search

    André Le Sauze; Lionel Montagne; Gérard Palavit; Franck Fayon; Roger Marchand

    2000-01-01

    In this study, the structure of mixed alkali nitrided phosphate glasses ‘LiNaPON’, of composition Li0.5Na0.5PO3?3x\\/2Nx(0phosphorus atoms, thus

  9. SUMMARY REVIEW OF HEALTH EFFECTS ASSOCIATED WITH ELEMENTAL AND INORGANIC PHOSPHORUS COMPOUNDS: HEALTH ISSUE ASSESSMENT

    EPA Science Inventory

    Phosphorus is a nonmetallic essential element. lthough phosphorus occurs naturally in the environment, most of the phosphorus in the environment occurs during its manufacture into one of the three allotropic forms (white, red, or black) or into phosphorus compounds and during the...

  10. Phosphorus fertilizer can increase pea and lentil yield on many Montana soils

    E-print Network

    Maxwell, Bruce D.

    , which tests for phosphorus levels in soils that are neutral to alkaline (pH greater than 7). Those soils to determine phosphorus fertilizer requirements." Soil phosphorus levels may be tested using the "Olsen P" testPhosphorus fertilizer can increase pea and lentil yield on many Montana soils December 15, 2006

  11. Humic acid applications to lettuce do not improve yield but do improve phosphorus availability

    Microsoft Academic Search

    K. Mesut Cimrin; Ismail Yilmaz

    2005-01-01

    The effects of humic acid (HA) and phosphorus (P) applications on plant growth and nutrient content of lettuce, together with available soil phosphorus remaining after harvest were examined. The amounts of phosphorus used were 0, 120, and 240 kg ha and those of humic acid were 0, 100, 200, and 300 kg ha. Phosphorus increased the nitrogen content of lettuce

  12. The story of phosphorus: Global food security and food for thought

    Microsoft Academic Search

    Dana Cordell; Jan-Olof Drangert; Stuart White

    2009-01-01

    Food production requires application of fertilizers containing phosphorus, nitrogen and potassium on agricultural fields in order to sustain crop yields. However modern agriculture is dependent on phosphorus derived from phosphate rock, which is a non-renewable resource and current global reserves may be depleted in 50–100 years. While phosphorus demand is projected to increase, the expected global peak in phosphorus production

  13. Utilization of phosphorus sources of different availability by mycorrhizal and non-mycorrhizal maize

    Microsoft Academic Search

    C. L. Murdoch; J. A. Jackobs; J. W. Gerdemann

    1967-01-01

    Summary In experiments with phosphorus sources of different availability mycorrhizal and non-mycorrhizal maize grew equally well when the phosphorus source was readily available. When the phosphorus source was slowly available, however, mycorrhizal maize had a much higher phosphorus content and grew much better than non-mycorrhizal maize.

  14. New Chiral Phosphorus Ligands for Enantioselective Hydrogenation Wenjun Tang and Xumu Zhang*

    E-print Network

    Zhang, Xumu

    New Chiral Phosphorus Ligands for Enantioselective Hydrogenation Wenjun Tang and Xumu Zhang, Pennsylvania 16802 Received January 29, 2003 Contents 1. Introduction 3029 2. Chiral Phosphorus Ligands: A Historical Overview 3030 2.1. Chiral Phosphorus Ligands from 1970 to 1980 3031 2.2. Chiral Phosphorus Ligands

  15. Ectopic expression of a soybean phytase in developing seeds of Glycine max to improve phosphorus availability

    E-print Network

    Finer, John J.

    Ectopic expression of a soybean phytase in developing seeds of Glycine max to improve phosphorus 2004 Key words: Glycine max, phosphorus, phytase expression, phytate, soybean, transgenic Abstract, phosphorus Introduction Phosphorus (P) is stored in plant seeds as phytate (also known as phytic acid, myo

  16. Leaf nitrogen to phosphorus ratios of tropical trees: experimental assessment of physiological and

    E-print Network

    Bermingham, Eldredge

    , and with or without added fertilizer containing nitrogen, phosphorus and potassium. · For plants grown under commonLeaf nitrogen to phosphorus ratios of tropical trees: experimental assessment of physiological words: leaf nitrogen concentration, leaf nitrogen to phosphorus ratio, leaf phosphorus concentration

  17. Removing Phosphorus and Nitrogen from Municipal Wastewater Using a Algae Biofilm Reactor

    Microsoft Academic Search

    Lizhen Xing; Yanhao Zhang; Jin Kong; Xiangyang Zhang

    2011-01-01

    With the consideration algae's biological function and excellent removals of nitrogen and phosphorus, Oscillatoria amoena was attached to the PE bundles in algae biofilm reactor to remove nitrogen and phosphorus the municipal wastewater. Flask experiment showed that the removals of nitrogen and phosphorus were reached to 92.1%, 100% respectively at ratio of nitrogen and phosphorus 10:1. The continuous running of

  18. Recovery oriented phosphorus adsorption process in decentralized advanced Johkasou.

    PubMed

    Ebie, Y; Kondo, T; Kadoya, N; Mouri, M; Maruyama, O; Noritake, S; Inamori, Y; Xu, K

    2008-01-01

    Decentralized advanced wastewater treatment using adsorption and desorption process for recovery and recycling oriented phosphorus removal was developed. Adsorbent particles made of zirconium were set in a column, and it was installed as subsequent stage of BOD and nitrogen removal type Johkasou, a household domestic wastewater treatment facility. The water quality of the effluent of adsorption column in a number of experimental sites was monitored. The effluent phosphorus concentration was kept below 1 mg l(-1) during 90 days at all the sites. Furthermore, over 80% of the sites achieved 1 mg l(-1) of T-P during 200 days. This adsorbent was durable, and deterioration of the particles was not observed over a long duration. The adsorbent collected from each site was immersed in alkali solution to desorb phosphorus. Then the adsorbent was reactivated by soaking in acid solution. The reactivated adsorbent was reused and showed almost the same phosphorus adsorption capacity as a new one. Meanwhile, the desorbed phosphorus was recovered with high purity as trisodium phosphate by crystallization. It is proposed as a new decentralized system for recycling phosphorus that paves the way to high-purity recovery of finite phosphorus. PMID:18587187

  19. Phosphorus removal in a surface-flow constructed wetland treating agricultural runoff.

    PubMed

    Beutel, Marc W; Morgan, Matthew R; Erlenmeyer, Jonathan J; Brouillard, Elaine S

    2014-05-01

    Agricultural runoff is a leading source of phosphorus (P) pollution to lakes and streams. The objective of this study was to evaluate P removal dynamics in a constructed treatment wetland (CTW) treating agricultural irrigation return flows. The CTW included a sedimentation basin (SB) followed by two surface-flow wetlands in parallel. Typical retention times and total P (TP) loading were 1.4 d and 50 to 110 g m yr P, respectively, for the SB and 5 to 6 d and 4 to 10 g m yr P, respectively, for wetlands. On the basis of this multiyear study, concentration removal efficiency in the SB averaged 21% for TP and 32% for reactive phosphorus (RP). Concentration removal efficiency in wetlands averaged 37 and 43% for TP and 22 and 33% for RP. Areal first-order removal rates for TP averaged 22 and 31 m yr in wetlands. Total P removal in wetlands exhibited a strong seasonal pattern, with minimum removal in the summer when high temperatures likely enhanced P release from decaying plant biomass. The performance of the CTW was stochastic, with removal unpredictably poorer in some years in part as a result of muskrat bioturbation and plant harvesting. In years before muskrat impacts, concentration removal efficiencies in wetlands were 50% for TP and 65% for RP. PMID:25602836

  20. Mycorrhizal Acquisition of Inorganic Phosphorus by the Green-leaved Terrestrial Orchid Goodyera repens

    PubMed Central

    Cameron, Duncan D.; Johnson, Irene; Leake, Jonathan R.; Read, David J.

    2007-01-01

    Background and Aims Mycorrhizal fungi play a vital role in providing a carbon subsidy to support the germination and establishment of orchids from tiny seeds, but their roles in adult orchids have not been adequately characterized. Recent evidence that carbon is supplied by Goodyera repens to its fungal partner in return for nitrogen has established the mutualistic nature of the symbiosis in this orchid. In this paper the role of the fungus in the capture and transfer of inorganic phosphorus (P) to the orchid is unequivocally demonstrated for the first time. Methods Mycorrhiza-mediated uptake of phosphorus in G. repens was investigated using spatially separated, two-dimensional agar-based microcosms. Results External mycelium growing from this green orchid is shown to be effective in assimilating and transporting the radiotracer 33P orthophosphate into the plant. After 7 d of exposure, over 10 % of the P supplied was transported over a diffusion barrier by the fungus and to the plants, more than half of this to the shoots. Conclusions Goodyera repens can obtain significant amounts of P from its mycorrhizal partner. These results provide further support for the view that mycorrhizal associations in some adult green orchids are mutualistic. PMID:17339276

  1. Phosphorus Loadings Associated with a Park Tourist Attraction: Limnological Consequences of Feeding the Fish

    NASA Astrophysics Data System (ADS)

    Turner, Andrew M.; Ruhl, Nathan

    2007-04-01

    The Linesville spillway of Pymatuning State Park is one of the most visited tourist attractions in Pennsylvania, USA, averaging more than 450,000 visitors · year-1. Carp ( Cyprinus carpio Linnaeus) and waterfowl congregate at the spillway where they are fed bread and other foods by park visitors. We hypothesized that the “breadthrowers” constitute a significant nutrient vector to the upper portion of Pymatuning Reservoir. In the summer of 2002, we estimated phosphorus loadings attributable to breadthrowers, and compared these values to background loadings from Linesville Creek, a major tributary to the upper reservoir. Items fed to fish included bread, donuts, bagels, canned corn, popcorn, corn chips, hot dogs, birthday cakes, and dog food. Phosphorus loading associated with park visitors feeding fish was estimated to be 3233 g day-1, and estimated P export from the Linesville Creek watershed was 2235 g·day-1. P loading attributable to breadthrowers exceeded that of the entire Linesville Creek watershed on 33 of the 35 days of study, with only a heavy rainfall event triggering watershed exports that exceeded spillway contributions. Averaged across 5 weeks, breadthrowers contributed 1.45-fold more P to Pymatuning Reservoir than the Linesville Creek watershed. If Linesville Creek P exports are extrapolated to the entire Sanctuary Lake watershed, spillway contributions of P added 48% to the non-point source watershed P entering the lake. Park visitors feeding fish at the Linesville Spillway are a significant source of nutrients entering Sanctuary Lake.

  2. Is the destabilisation of lake peipsi ecosystem caused by increased phosphorus loading or decreased nitrogen loading?

    PubMed

    Nõges, T; Laugaste, R; Loigu, E; Nedogarko, I; Skakalski, B; Nõges, P

    2005-01-01

    Lake Peipsi (3555 km2, mean depth 7.1 m) located on the border of Estonia and Russia is the largest transboundary lake in Europe. L. Peipsi consists of three parts. The shared largest northern part L. Peipsi s.s. (2611 km2, 8.3 m) and the southern L. Pihkva (708 km2, 3.8 m) which belongs mainly to Russia are connected by the river-shaped L. Lämmijärv (236 km2, 2.5 m). The catchment area (44,245 km2 without lake area) is shared between Estonia (33.3%), Russia (58.6%) and Latvia (8%). Intensive eutrophication of L. Peipsi started in the 1970s. The biomass of N2-fixing cyanobacteria was low at heavy nutrient loading in the 1980s. After the collapse of soviet-type agriculture in the early 1990s, the loading of nitrogen sharply decreased. A certain improvement of L. Peipsi s.s. was noticed at the beginning of the 1990s together with the temporary reduction of phosphorus loading from Estonian catchment while in recent years a destabilisation of the ecosystem has been observed. This deterioration has been expressed mainly as intensive blue-green blooms and fish-kills in summer. Reappearance of blooms has been explained by the decrease in N/P loading ratio due to reduced N discharge while in some periods increased phosphorus loading could have supported this trend. PMID:15850199

  3. Typhoon effects on phosphorus dynamics in a subtropical reservoir

    NASA Astrophysics Data System (ADS)

    Chow, Ming Fai

    2013-04-01

    Intense storm event during typhoon period is identified that will significantly alter the content of phosphorus in the water body of reservoir. However, the fate and transport of phosphorus in aquatic environments that triggered by typhoons is poorly understanded. Better understanding of typhoon impacts on the runoff mechanism of phosphorus will be useful in improving the management of water pollution and reduce the impairment to the drinking water sources. In this study, three typhoon events namely Talim, Saola and Tembin which occurred in between June and August 2012 were investigated through continuous sampling (every 3 hours) at five main tributaries at the upstream of Fei-Tsui reservoir, Taiwan. In addition, weekly sampling was conducted at different depths throughout the water column at the dam site. For all water samples, in situ measurements of pH, temperature, electrical conductivity (EC) and dissolved oxygen (DO) were conducted. The water samples had been analysed for total suspended solid (TSS), dissolved inorganic phosphorus (DIP), dissolved organic phosphorus (DOP), particulate phosphorus (PP) and total phosphorus (TP). Results indicated that high intense typhoon storm had caused a 2-10 times increase in DIP compared with the moderate storm and base flow condition. Correlation analysis showed that TP was positively correlated with TSS. That indicates the turbidity current can be a source of phosphorus. All nutrients showed a contrasting hysteresis pattern, which reflecting different supply of source and transport mechanism. PP was mainly originated from overland surface runoff and resuspension of sediment from the river bottom, while DIP was supplied from both surface and subsurface flow. High PP concentration was observed during the early part of storm runoff at the upstream river. Results suggested that first flush effect was evident for PP. These findings had improved the understanding on fate and transport of phosphorus in the reservoir watershed during the typhoon induced storm events.

  4. Copper-phosphorus alloys offer advantages in brazing copper

    SciTech Connect

    Rupert, W.D. [Engelhard Corp., Warwick, RI (United States)

    1996-05-01

    Copper-phosphorus brazing alloys are used extensively for joining copper, especially refrigeration and air-conditioning copper tubing and electrical conductors. What is the effect of phosphorus when alloyed with copper? The following are some of the major effects: (1) It lowers the melt temperature of copper (a temperature depressant). (2) It increases the fluidity of the copper when in the liquid state. (3) It acts as a deoxidant or a fluxing agent with copper. (4) It lowers the ductility of copper (embrittles). There is a misconception that silver improves the ductility of the copper-phosphorus alloys. In reality, silver added to copper acts in a similar manner as phosphorus. The addition of silver to copper lowers the melt temperature (temperature depressant) and decreases the ductility. Fortunately, the rate and amount at which silver lowers copper ductility is significantly less than that of phosphorus. Therefore, taking advantage of the temperature depressant property of silver, a Ag-Cu-P alloy can be selected at approximately the same melt temperature as a Cu-P alloy, but at a lower phosphorus content. The lowering of the phosphorus content actually makes the alloy more ductile, not the silver addition. A major advantage of the copper-phosphorus alloys is the self-fluxing characteristic when joining copper to copper. They may also be used with the addition of a paste flux on brass, bronze, and specialized applications on silver, tungsten and molybdenum. Whether it is selection of the proper BCuP alloy or troubleshooting an existing problem, the suggested approach is a review of the desired phosphorus content in the liquid metal and how it is being altered during application. In torch brazing, a slight change in the oxygen-fuel ratio can affect the joint quality or leak tightness.

  5. Effect of phosphorus and nitrogen on flame retardant cellulose: A study of phosphorus compounds

    Microsoft Academic Search

    Sabyasachi Gaan; Gang Sun

    2007-01-01

    Three organophosphorus compounds, N-hydroxymethyl-3-dimethylphosphonopropionamide (HDPP), triallyl phosphate (TAP) and triallyl phosphoramide were employed in a study on flame retardant (FR) mechanisms. N-hydroxymethyl-3-dimethylphosphonopropionamide was more efficient in providing flame retardancy to cellulosic fabrics at the same phosphorus content on cotton fabrics. The flame retardance of the flame retardant treated cotton fabrics were characterized by using limiting oxygen index (LOI). Structural changes

  6. Impact of fertilizer phosphorus application on phosphorus release kinetics in some calcareous soils

    Microsoft Academic Search

    A. R. Hosseinpur; F. S. Biabanaki

    2009-01-01

    Phosphate reactions and retention in the soil are of paramount importance from the perspective of plant nutrition and fertilizer\\u000a use efficiency. The objective of this work was to study the kinetics of phosphorus (P) desorption in different soils of Hamadan\\u000a in fertilized and unfertilized soils. Soils were fertilized with 200 mg P kg?1. Fertilized and unfertilized soils were incubated at 25 ± 1°C for 6 months.

  7. Site-Specific Phosphorus Application Based on the Kriging Fertilizer-Phosphorus Availability Index of Soils

    Microsoft Academic Search

    Kai-Wei Juang; Day-Chyng Liou; Dar-Yuan Lee

    2002-01-01

    ABSTRACT,is also dependent upon the P-fixation tendency of soil. An alternative approach,to soil testing that considers Site-specific phosphorus management is done to optimize crop the recovery,rate of P application to improve,fertilizer production and minimize P loss from soils. The spatial variability of the recommendations has been proposed (McLean et al., available P prior to fertilizer application and the P-fixation tendency

  8. Mass transfer of phosphorus in high-phosphorus hot-metal refining

    NASA Astrophysics Data System (ADS)

    Diao, Jiang; Liu, Xuan; Zhang, Tao; Xie, Bing

    2015-03-01

    Mass transfer of phosphorus in high-phosphorus hot-metal refining was investigated using CaO-Fe t O-SiO2 slags at 1623 K. Based on a two-film theory kinetic model and experimental results, it was found that the overall mass transfer coefficient, which includes the effects of mass transfer in both the slag phase and metal phase, is in the range of 0.0047 to 0.0240 cm/s. With the addition of a small amount of fluxing agents Al2O3 or Na2O into the slag, the overall mass transfer coefficient has an obvious increase. Silicon content in the hot metal also influences the overall mass transfer coefficient. The overall mass transfer coefficient in the lower [Si] heat is much higher than that in the higher [Si] heat. It is concluded that both fluxing agents and lower [Si] hot metal facilitate mass transfer of phosphorus in liquid phases. Furthermore, the addition of Na2O could also prevent rephosphorization at the end of the experiment.

  9. Phosphorus-phosphorus coupling in a diphosphine with a ten bond P...P separation.

    PubMed

    Kuhn, P; Jeunesse, C; Matt, D; Harrowfield, J; Ricard, L

    2006-07-28

    The large, unsymmetrical diphosphine 5,11,17,23-tetra-tert-butyl-25,26-bis(diphenylphosphinomethoxy)-27(or 28)-benzoyloxy-28(or 27)-hydroxycalix[4]arene, in which the phosphorus atoms are separated by ten bonds, was prepared by monobenzoylation of 5,11,17,23-tetra-tert-butyl-25,26-bis(diphenylphosphinoylmethoxy)-27,28-bis(hydroxy)calix[4]arene, followed by reduction with phenyl silane. Its molecular structure has been determined by X-ray crystallography. In the solid state, the phosphorus atoms are separated by 5.333(1) A. NMR investigations reveal an unexpected "through-space"J(PP') coupling constant of 8.0 Hz and also show that, in solution, the calixarene is conformationally mobile, the phenoxy ring flipping rapidly through the calixarene annulus. The spatial proximity of the two phosphorus atoms was further demonstrated by the ease of obtaining the cis-chelate complex [Pd(eta3-C3H4Me)(THF)2]BF4 (THF = tetrahydrofuran). PMID:16832495

  10. 30 CFR 33.33 - Allowable limits of dust concentration.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS DUST COLLECTORS FOR USE IN CONNECTION WITH ROCK DRILLING IN COAL MINES Test Requirements § 33.33 Allowable limits of dust concentration. (a) The...

  11. 30 CFR 33.33 - Allowable limits of dust concentration.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS DUST COLLECTORS FOR USE IN CONNECTION WITH ROCK DRILLING IN COAL MINES Test Requirements § 33.33 Allowable limits of dust concentration. (a) The...

  12. 30 CFR 33.33 - Allowable limits of dust concentration.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS DUST COLLECTORS FOR USE IN CONNECTION WITH ROCK DRILLING IN COAL MINES Test Requirements § 33.33 Allowable limits of dust concentration. (a) The...

  13. 30 CFR 33.33 - Allowable limits of dust concentration.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS DUST COLLECTORS FOR USE IN CONNECTION WITH ROCK DRILLING IN COAL MINES Test Requirements § 33.33 Allowable limits of dust concentration. (a) The...

  14. 30 CFR 33.33 - Allowable limits of dust concentration.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS DUST COLLECTORS FOR USE IN CONNECTION WITH ROCK DRILLING IN COAL MINES Test Requirements § 33.33 Allowable limits of dust concentration. (a) The...

  15. Plant uptake of phosphorus and nitrogen recycled from synthetic source-separated urine.

    PubMed

    Bonvin, Christophe; Etter, Bastian; Udert, Kai M; Frossard, Emmanuel; Nanzer, Simone; Tamburini, Federica; Oberson, Astrid

    2015-03-01

    Urine contains about 50 % of the phosphorus (P) and about 90 % of the nitrogen (N) excreted by humans and is therefore an interesting substrate for nutrient recovery. Source-separated urine can be used to precipitate struvite or, through a newly developed technology, nitrified urine fertilizer (NUF). In this study, we prepared (33)P radioisotope- and stable (15)N isotope-labeled synthetic NUF (SNUF) and struvite using synthetic urine and determined P and N uptake by greenhouse-grown ryegrass (Lolium multiflorum var. Gemini) fertilized with these products. The P and N in the urine-based fertilizers were as readily plant-available in a slightly acidic soil as the P and N in reference mineral fertilizers. The ryegrass crop recovered 26 % of P applied with both urine-based fertilizers and 72 and 75 % of N applied as struvite and SNUF, respectively. Thus, NUF and urine-derived struvite are valuable N and P recycling fertilizers. PMID:25681979

  16. Key structure-activity relationships in the vanadium phosphorus oxide catalyst system

    SciTech Connect

    Thompson, M.R. (Pacific Northwest Lab., Richland, WA (USA)); Ebner, J.R. (Monsanto Co., St. Louis, MO (USA))

    1990-04-01

    The crystal structure of vanadyl pyrophosphate has been redetermined using single crystals obtained from a near solidified melt of a microcrystalline catalyst sample. Crystals that index as vanadyl pyrophosphate obtained from this melt are variable in color. Crystallographic refinement of the single crystal x-ray diffraction data indicates that structural differences among these materials can be described in terms of crystal defects associated with linear disorder of the vanadium atoms. The importance of the disorder is outlined in the context of its effect on the proposed surface topology parallel to (1,0,0). Models of the surface topology simply and intuitively account for the non-stoichometric surface atomic P/V ratio exhibited by selective catalysts of this phase. These models also point to the possible role of the excess phosphorus in providing site isolation of reactive centers at the surface. 33 refs., 7 figs.

  17. Determination of clemastine in human plasma by gas chromatography with nitrogen-phosphorus detection.

    PubMed

    Davydova, N N; Yasuda, S U; Woosley, R L; Wainer, I W

    2000-07-01

    A method for the quantitative determination of clemastine in human plasma has been developed and validated. The assay uses gas chromatography with nitrogen-phosphorus detection and a HP-1 capillary column (25 mx0.22 mm, film thickness 0.33 mm) coated with dimethylpolysiloxane. Clemastine (with orphenadrine as internal standard) was isolated from human plasma using liquid-liquid extraction. A linear relationship was observed between 0.1 and 12.8 ng/ml using the peak area ratio of clemastine to orphenadrine with a correlation coefficient greater than 0.99 (the detection limit for clemastine was 0.06 ng/ml). The intra- and inter-day coefficients of variation were less than 11%. The developed method was used for the analysis of plasma samples from healthy volunteers (n = 19) to examine the pharmacokinetics of the antihistamine clemastine after single and multiple oral doses of clemastine fumarate. PMID:10985579

  18. Tunable optical properties of multilayer black phosphorus thin films

    NASA Astrophysics Data System (ADS)

    Low, Tony; Rodin, A. S.; Carvalho, A.; Jiang, Yongjin; Wang, Han; Xia, Fengnian; Castro Neto, A. H.

    2014-08-01

    Black phosphorus thin films might offer attractive alternatives to narrow-gap compound semiconductors for optoelectronics across mid- to near-infrared frequencies. In this work, we calculate the optical conductivity tensor of multilayer black phosphorus thin films using the Kubo formula within an effective low-energy Hamiltonian. The optical absorption spectra of multilayer black phosphorus are shown to vary sensitively with thickness, doping, and light polarization. In conjunction with experimental spectra obtained from infrared absorption spectroscopy, we also discuss the role of interband coupling and disorder on the observed anisotropic absorption spectra.

  19. Evaluation of the calcium and phosphorus requirement of developing boars

    E-print Network

    Schroeder, James

    1973-01-01

    by dietary treatment on day 56; however, a significant (P&. 10) phosphorus linear x Ca:P ratio interaction effect on serum calcium values was found. Based on the results of this experiment, 0. 50X dietary phos- phorus and 0. 50X dietary calcium.... The percentage of calcium and phosphorus in the dicalcium phosphate was also determined prior to initiating the experiment. Six diets (18X protein} with dif- ferent calcium and phosphorus levels were formulated based on the chemical analysis of the feedstuffs...

  20. Plasmonics in strained monolayer black phosphorus

    NASA Astrophysics Data System (ADS)

    Lam, Kai-Tak; Guo, Jing

    2015-03-01

    Monolayer black phosphorus (BP) has high band anisotropy which can be modulated with strain. We show that the plasmonic dispersions in monolayer BPs not only strongly depend on the crystalline direction but also strain. Application of strain can alter the optimum direction for plasmon transport and engineer the anisotropic plasmonic dispersion relations. Furthermore, we evaluate the plasmon losses and wave localization via the random-phase approximation framework. It is found that although the BP monolayer is inferior to graphene in terms of loss at the same wave localization, it outperforms monolayer MoS2. The dependence of plasmon properties on the applied strain in BP makes it an interesting nanophotonic material, as well as a potential medium for piezo-optic applications.

  1. Dirac fermions in blue-phosphorus

    NASA Astrophysics Data System (ADS)

    Li, Yuanchang; Chen, Xiaobin

    2014-12-01

    We propose that Dirac cones can be engineered in phosphorene with fourfold-coordinated phosphorus atoms. The key is to separate the energy levels of the in-plane (s, px, and py) and out-of-plane (pz) oribtals through the sp2 configuration, yielding respective ?- and ?-character Dirac cones, and then quench the latter. As a proof-of-principle study, we create ?-character Dirac cones in hydrogenated and fluorinated phosphorene with a honeycomb lattice. The obtained Dirac cones are at K-points, slightly anisotropic, with Fermi velocities of 0.91 and 1.23 times that of graphene along the ?K and KM direction, and maintain good linearity up to ˜2 eV for holes. A substantive advantage of a ?-character Dirac cone is its convenience in tuning the Dirac gap via in-plane strain. Our findings pave the way for development of high-performance electronic devices based on Dirac materials.

  2. A Novel Method for Dissolved Phosphorus Analysis

    NASA Astrophysics Data System (ADS)

    Berry, J. M.; Spiese, C. E.

    2012-12-01

    High phosphorus loading is a major problem in the Great Lakes watershed. Phosphate enters waterways via both point and non-point sources (e.g., runoff, tile drainage, etc.), promoting eutrophication, and ultimately leading to algal blooms, hypoxia and loss of aquatic life. Quantification of phosphorus loading is typically done using the molybdenum blue method, which is known to have significant drawbacks. The molybdenum blue method requires strict control on time, involves toxic reagents that have limited shelf-life, and is generally unable to accurately measure sub-micromolar concentrations. This study aims to develop a novel reagent that will overcome many of these problems. Ethanolic europium(III) chloride and 8-hydroxyquinoline-5-sulfonic acid (hqs) were combined to form the bis-hqs complex (Eu-hqs). Eu-hqs was synthesized as the dipotassium salt via a simple one-pot procedure. This complex was found to be highly fluorescent (?ex = 360 nm, ?em = 510 nm) and exhibited a linear response upon addition of monohydrogen phosphate. The linear response ranged from 0.5 - 25 ?M HPO42- (15.5 - 775 ?g P L-1). It was also determined that Eu-hqs formed a 1:1 complex with phosphate. Maximum fluorescence was found at a pH of 8.50, and few interferences from other ions were found. Shelf-life of the reagent was at least one month, twice as long as most of the molybdenum blue reagent formulations. In the future, field tests will be undertaken in local rivers, lakes, and wetlands to determine the applicability of the complex to real-world analysis.

  3. Agricultural trade and the global phosphorus cycle

    NASA Astrophysics Data System (ADS)

    Schipanski, M.; Bennett, E.; Riskin, S.; Porder, S.

    2012-12-01

    Trends of increasing agricultural trade, increased concentration of livestock production systems, and increased human consumption of livestock products influence the distribution of nutrients across the global landscape. Phosphorus (P) represents a unique management challenge as we are rapidly depleting mineable reserves of this essential and non-renewable resource. At the same time, its overuse can lead to pollution of aquatic ecosystems. We analyzed the relative contributions of food crop, feed crop, and livestock product trade to P flows through agricultural soils for twelve countries from 1961 to 2007. We then used case studies of P fertilizer use in the world's three major soybean export regions: Iowa (USA), Mato Grosso (Brazil), and Buenos Aires (Argentina) to examine the influence of historical P management and soil types on agriculture's environmental consequences. Due to the intensification of agricultural production, average soil surface P balances more than tripled from 6 to 21 kg P per ha between 1961 and 2007 for the twelve study countries. Consequently, countries that are primarily agricultural exporters carried increased risks for water pollution or, for Argentina, reduced soil fertility due to soil P mining to support exports. In 2007, nations imported food and feed from regions with higher apparent P fertilizer use efficiencies than if those crops were produced domestically. However, this was largely because imports were sourced from regions depleting soil P resources to support export crop production. In addition, the pattern of regional specialization and intensification of production systems also reduced the potential to recycle P resources, with greater implications for livestock production than crop production. In a globalizing world, it will be increasingly important to integrate biophysical constraints of our natural resources and environmental impacts of agricultural systems into trade policy and agreements and to develop mechanisms that move us closer to more equitable management of non-renewable resources such as phosphorus.

  4. Is phosphorus intake that exceeds dietary requirements a risk factor in bone health?

    PubMed

    Calvo, Mona S; Tucker, Katherine L

    2013-10-01

    Phosphorus intake in excess of the nutrient needs of healthy adults is thought to disrupt hormonal regulation of phosphorus (P), calcium (Ca), and vitamin D, contributing to impaired peak bone mass, bone resorption, and greater risk of fracture. Elevation of extracellular phosphorus due to excessive intake is thought to be the main stimulus disrupting phosphorus homeostasis in healthy individuals, as it is in renal disease even when intake is modest. If high serum phosphorus is the critical link to the effect of high phosphorus intake on bone health, the issue could be addressed through epidemiologic or dietary studies. However, several confounding factors, including problems estimating accurate phosphorus intake, the influence of a low dietary Ca:P ratio, the acidic nature of phosphorus, the rapid rate of absorption and greater phosphorus bioavailability from processed food such as cola drinks, and circadian fluctuation in serum phosphorus, make this question difficult to address using conventional study designs. These confounding factors are considered in this review, exploring whether phosphorus intake exceeding nutrient needs in healthy individuals disrupts phosphorus regulation and negatively affects bone accretion or loss. Specific attention is given to phosphorus intake from processed foods rich in phosphorus additives, which significantly contribute to phosphorus intake. PMID:24472074

  5. X-33. Phase 2

    NASA Technical Reports Server (NTRS)

    1998-01-01

    In response to the Cooperative Agreement, Lockheed Martin Skunk Works has compiled an Annual Performance Report of the X-33/RLV Program. This report consists of individual reports from all industry team members, as well as NASA team centers. The first milestone was hand delivered to NASA MSFC. The second year has been one of significant accomplishment in which team members have demonstrated their ability to meet vital benchmarks while continuing on the technical adventure of the 20th century.

  6. Black phosphorus photodetector for multispectral, high-resolution imaging.

    PubMed

    Engel, Michael; Steiner, Mathias; Avouris, Phaedon

    2014-11-12

    Black phosphorus is a layered semiconductor that is intensely researched in view of applications in optoelectronics. In this letter, we investigate a multilayer black phosphorus photodetector that is capable of acquiring high-contrast (V > 0.9) images both in the visible (?VIS = 532 nm) as well as in the infrared (?IR = 1550 nm) spectral regime. In a first step, by using photocurrent microscopy, we map the active area of the device and we characterize responsivity and gain. In a second step, by deploying the black phosphorus device as a point-like detector in a confocal microsope setup, we acquire diffraction-limited optical images with submicron resolution. The results demonstrate the usefulness of black phosphorus as an optoelectronic material for hyperspectral imaging applications. PMID:25299161

  7. Black Phosphorus Photodetector for Multispectral, High-Resolution Imaging

    NASA Astrophysics Data System (ADS)

    Engel, Michael; Steiner, Mathias; Avouris, Phaedon

    2014-11-01

    Black phosphorus is a layered semiconductor that is intensely researched in view of applications in optoelectronics. In this Letter, we investigate a multi-layer black phosphorus photo-detector that is capable of acquiring high-contrast (V>0.9) images both in the visible ({\\lambda}_{VIS}=532nm) as well as in the infrared ({\\lambda}_{IR}=1550nm) spectral regime. In a first step, by using photocurrent microscopy, we map the active area of the device and we characterize responsivity and gain. In a second step, by deploying the black phosphorus device as a point-like detector in a confocal microsope setup, we acquire diffraction-limited optical images with sub-micron resolution. The results demonstrate the usefulness of black phosphorus as an optoelectronic material for hyperspectral imaging applications.

  8. A quantitative phosphorus loss assessment tool for agricultural fields

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Conservation and nutrient management planners need an assessment tool to accurately predict phosphorus (P) loss from agricultural lands. Available tools are either qualitative indices with limited capability to quantify offsite water quality impacts or prohibitively complex quantitative process-bas...

  9. The availability of dissolved organic phosphorus compounds to marine phytoplankton

    NASA Astrophysics Data System (ADS)

    Hua-Sheng, Hong; Hai-Li, Wang; Bang-Qin, Huang

    1995-06-01

    The availability of three dissolved organic phosphorus (DOP) compounds as nutrient sources for experimental culture of three algae was studied. Results indicated that these compounds could be utilized by algae, and that dissolved inorganic phosphorus (DIP) was first to be uptaken when various forms of phosphorus (DIP and DOP) co-existed. Dicrateria zhanjiangensis' uptake of sodium glycerophosphate was faster than that of D-ribose-5-phosphate. The increase of sodium glycerophosphate had little effect on the maximum uptake rate( V max) of Chlorella sp., but increased the semisaturation constant( K s) remarkably; the photosynthesis rates(PR) of Dicrateria zhanjiangensis and Chlorella sp. were rarely affected by using various forms of phosphorus in the culture experiments. The possible DOP pathways utilized by algae are discussed.

  10. Reactive Phosphorus Removal from Aquaculture and Poultry Productions

    E-print Network

    Rubloff, Gary W.

    aquaculture waste discharges, rich in nutrients. Poultry litter, also referred to as broiler litter phosphorus (P) levels in agricultural soils to which it is applied as fertilizer. The litter is removed from

  11. Difference in Phosphorus Levels Between African and European Honeybees

    E-print Network

    Hall, Sharon J.

    Difference in Phosphorus Levels Between African and European Honeybees By Matthew Harwood, Dina Grayson & Jennifer H. Fewell Arizona State University Introduction African honeybees hurt agriculture by replacing European honeybee colonies raised for agricultural purposes. African honeybees have been a problem

  12. Asteroidal Impact Caused Phosphorus Flooding on the Earth During Palaeoproterozoic

    NASA Astrophysics Data System (ADS)

    Sisodia, M. S.; Mishra, S.; Purohit, R.; Purohit, V.

    2013-09-01

    The abrupt contact between carbonate and phosphate stromatolites at Udaipur, India of Palaeoproterozoic age indicates asteroidal impact that inundated the Earth with phosphorus. Resultant cyanobacterial bloom changed the Earth's overall environment.

  13. Reducing Phosphorus in Dairy Effluent Wastewater through Flocculation and Precipitation

    E-print Network

    Bragg, A.

    2003-01-01

    The objective of my research is to find methods to reduce the phosphorus concentration in dairy effluent wastewater through removal of suspended solids and precipitation of calcium or magnesium-ammonium phosphates....

  14. A single phosphorus treatment doubles growth of cyanobacterial lichen transplants.

    PubMed

    McCune, Bruce; Caldwell, Bruce A

    2009-02-01

    Lichens are reputedly slow growing and become unhealthy or die in response to supplements of the usual limiting resources, such as water and nitrogen. We found, however, that the tripartite cyanobacterial lichen Lobaria pulmonaria doubled in annual biomass growth after a single 20-minute immersion in a phosphorus solution (K2HPO4), as compared to controls receiving no supplemental phosphorus. This stimulation of cyanolichens by phosphorus has direct relevance to community and population ecology of lichens, including improving models of lichen performance in relation to air quality, improving forest management practices affecting old-growth associated cyanolichens, and understanding the distribution and abundance of cyanolichens on the landscape. Phosphorus may be as important a stimulant to cyanobacterial-rich lichen communities as it is to cyanobacteria in aquatic ecosystems. PMID:19323240

  15. Phosphorus Determination by Derivative Activation Analysis: A Multifaceted Radiochemical Application.

    ERIC Educational Resources Information Center

    Kleppinger, E. W.; And Others

    1984-01-01

    Although determination of phosphorus is important in biology, physiology, and environmental science, traditional gravimetric and colorimetric methods are cumbersome and lack the requisite sensitivity. Therefore, a derivative activation analysis method is suggested. Background information, procedures, and results are provided. (JN)

  16. Novel Mechanisms in the Regulation of Phosphorus Homeostasis - Figure 3

    NSDL National Science Digital Library

    Theresa Berndt (Mayo Clinic)

    2009-02-01

    This figure shows that intestinal phosphate sensing increases the fractional excretion of phosphorus in the kidney following increases in intestinal luminal phosphate concentrations by the release of an intestinal mediator ("intestinal phosphatonin").

  17. Europe supplies substantial aerosol phosphorus to the Mediterranean

    NASA Astrophysics Data System (ADS)

    Wendel, JoAnna

    2014-10-01

    Biologically unproductive ocean regions depend on the wind to transport necessary nutrients, such as phosphorus, from the land. In the Mediterranean Sea, winds from Europe and North Africa bring phosphorus-laden dust particles and aerosols to remote waters. Previous research assumed that North Africa is the primary source of these particles because large Saharan dust storms create red rain events across the Mediterranean, making them an obvious source of nutrients.

  18. The release of dissolved phosphorus from lake sediments

    Microsoft Academic Search

    P. C. M. Boers

    1991-01-01

    Chapter 1. Introduction:<\\/strong> Eutrophication is one of the world's major water quality problems. Attempts to alleviate eutrophication of lakes have involved the control of phosphorus loadings. In such cases, an internal loading of phosphorus from the sediments may retard an improvement of the water quality. Chapters 2 - 5 deal specifically with the sediments of Lake Loosdrecht.Chapter 2. Distribution and

  19. Reactions of Halides of Tervalent Phosphorus with Imines and -Diimines

    Microsoft Academic Search

    A. M. Kibardin; T. V. Gryaznova; P. I. Gryaznov; E. Ya. Levi-Na; I. A. Litvinov; V. A. Naumov; Yu. B. Mikhailov; A. N. Pudovik; A. E. Arbuzov

    1990-01-01

    Isobutylidenebutylamine reacts with phosphorus trichloride in the presence of organic bases to give N-butyl-N-isobutenylamidodichloro-or bis(N-butyl-N-isobutenylamido)chlorophosphites depending on the ratio of reagents. Reasons are given in Eavour of the reaction beginning with the nucleophilic attack of the nitrogen atom of the imine on the electrondeficient phosphorus atom of the chloride. Reactions of ethyldichloro- and diethylchlorophosphites with benzylidenmethylamine produce 2-chloro- and 2-ethyl-2-oxo-1,4,2-diazaphospholanes

  20. Theoretical study of the cyclotriphosphazenes importance of phosphorus d orbitals

    NASA Astrophysics Data System (ADS)

    Haddon, R. C.

    1985-10-01

    The nature of the bonding and the degree of delocalization in the phosphazenes has been controversial for more than twenty five years. An Important aspect of this discussion revolves around the question of phosphorus d-orbital participation in the phosphazene bond. In the present communication I report theoretical calculations on a series of cyclotriphosphazene derivatives which strongly suggest that from a structural point of view, phosphorus d orbitals are significant participants in the ring bonds.

  1. Methods of Supplying Phosphorus to Range Cattle in South Texas.

    E-print Network

    Kleberg, R. J. Jr.; Fudge, J. F.; Jones, J. H.; Jones, J. M.; Reynolds, E. B.

    1953-01-01

    . triple superphosphate 2 7 400 lbs. triple superphosphate 14 200 lbs. triple superphosphate 11 100 lbs. triple superphosphate 7 164 lbs. potassium metaphosphatel 10 162 lbs. calcium metaphosphatel 10 None 4 Treatment per acre Fused phosphate plots... and disodium phosphate - prevented phosphorus deficiency and corrected already existing deficiencies if they were not too far advanced. Additional work was conducted from 1941 to 1946 to develop more practical methods of supplying phosphorus to cattle...

  2. Electrodeposition of amorphous ternary nickel-chromium-phosphorus alloy

    DOEpatents

    Guilinger, Terry R. (Albuquerque, NM)

    1990-01-01

    Amorphous ternary nickel-chromium-phosphorus alloys are electrodeposited from a bath comprising a nickel salt, a chromium salt, a phosphorus source such as sodium hypophosphite, a complexing agent for the nickel ions, supporting salts to increase conductivity, and a buffering agent. The process is carried out at about room temperature and requires a current density between about 20 to 40 A/dm.sup.2.

  3. Microbial phytases in phosphorus acquisition and plant growth promotion

    Microsoft Academic Search

    Bijender Singh; T. Satyanarayana

    2011-01-01

    Phosphorus (P) is one of the major constituents in energy metabolism and biosynthesis of nucleic acids and cell membranes\\u000a with an important role in regulation of a number of enzymes. Soil phosphorous is an important macronutrient for plant growth.\\u000a Phosphorus deficiency in soil is a major problem for agricultural production. Total soil P occurs in either organic or in\\u000a organic

  4. Calcium and phosphorus requirements of bobwhite quail chicks

    USGS Publications Warehouse

    Nestler, R.B.; DeWitt, J.B.; Derby, J.V.; Moschler, M.

    1948-01-01

    Four experiments involving 873 bob-white quail (Colinus virginianus) chicks were conducted at the Patuxent Research Refuge, Laurel, Maryland. A comparison was made of calcium: phosphorus ratios of 1:1, 15:1, 1%: 1, 2:1, 2+:1,and 2%: 1in diets with phosphorus levels of 0.52, 0.75, 1.00, and 1.25 percent. The results indicate that the optimum level of phosphorus for growth is in the neighborhood of 0.75 per cent, and that of calcium is about 1.00 per cent, making a ratio of 1 1/3: 1....Although the greatest efficiency of feed utilization occurred on the phosphorus level of 0.52 per cent, the liveweight and bone-ash of the birds at the end of ten weeks were significantly lower than they were on the levels of 0.75 and 1.00 per cent, phosphorus. Bone-ash of birds on a Ca: P ratio of 1:1was significantly lower than that on any of the other five ratios, regardless of phosphorus level....There was a significant reverse correlation between the Ca: P ratio of the diet and the storage of vitamin A in the liver. Storage was especially low on the ratio of 2 2/3: 1....The low and high levels of calcium and phosphorus considered in these studies are abnormal, the low level especially being hard to obtain with common feedstuffs, if the protein requirements of the birds are met. Nevertheless, even on such levels, results were not disastrous. The growth of quail in the wild happens during a season when the birds have access to the minerals of the soil and in the abundant animal matter (mostly insects), as well as to minerals in plant material. Therefore, seemingly, calcium and phosphorus need not be critical nutrients for growing quail in the wild.

  5. Soils - Part 6: Phosphorus and Potassium in the Soil

    NSDL National Science Digital Library

    This lesson explains the importance of phosphorus fixation and describes methods for applying phosphorus and the advantages (and disadvantages) of each. It also describes the three forms of potassium and how form determines availability of potassium to plants.[This lesson, as well as the other nine lessons in the Soils series, is taken from the "Soils Home Study Course," published in 1999 by the University of Nebraska Cooperative Extension.

  6. Effects of soil phosphorus on pollen production, pollen size, pollen phosphorus content, and the ability to sire seeds in Cucurbita pepo (Cucurbitaceae)

    Microsoft Academic Search

    Tak-Cheung Lau; Andrew G. Stephenson

    1994-01-01

    To determine the effects of soil phosphorus on pollen production, pollen grain size, phosphate concentration per pollen grain, and the siring ability of pollen, two cultivars of the common zucchini (Cucurbita pepo) were grown under two soil phosphorus conditions in an experimental garden. Overall, soil phosphorus availability had a significant effect on reproductive output through the female function and on

  7. Phosphorus fractions of floodplain sediments and phosphorus exchange on the sediment–water interface in the lower reaches of the Han River in China

    Microsoft Academic Search

    J. R. Tian; P. J. Zhou

    2007-01-01

    Phosphorus fractions and phosphate adsorption characteristics of the floodplain sediments in the lower reaches of the Han River in China were investigated in order to provide the environmental managers with essential data on the Han River ecosystem. The results showed that the total phosphorus (TP) contents ranged from 643.86 to 985mgkg?1; inorganic phosphorus (IP) was the major fraction of TP,

  8. Balancing nutrition and serum phosphorus in maintenance dialysis.

    PubMed

    Fouque, Denis; Horne, Rob; Cozzolino, Mario; Kalantar-Zadeh, Kamyar

    2014-07-01

    Elevated serum phosphorus levels are common in patients with chronic kidney disease and are associated with heart and vascular disease, conditions that in turn are associated with increased mortality. Accurately managing phosphorus intake by restricting dietary protein alone can prove challenging because protein from different sources can contain varying amounts of available phosphorus. Additives used in processed foods frequently are high in inorganic phosphorus, which is readily absorbed, compounding this difficulty. Recent evidence suggests that dietary protein restriction in some cases may do more harm than good in some patients treated with maintenance hemodialysis because protein restriction can lead to protein-energy wasting, which is associated with increased mortality. Accordingly, phosphorus binders are important for managing hyperphosphatemia in dialysis patients. Managing hyperphosphatemia in patients with late-stage chronic kidney disease requires an individualized approach, involving a combination of adequate dietary advice, phosphate-binder use, and adjustments to dialysis prescription. We speculate that increased use of phosphate binders could allow patients to eat more protein-rich foods and that communicating this to patients might increase their perception of their need for phosphate binders, providing an incentive to improve adherence. The aim of this review is to discuss the challenges involved in maintaining adequate nutrition while controlling phosphorus levels in patients on maintenance hemodialysis therapy. PMID:24819675

  9. Thermal conduction in single-layer black phosphorus: highly anisotropic?

    PubMed

    Jiang, Jin-Wu

    2015-02-01

    The single-layer black phosphorus is characteristic for its puckered structure, which has led to distinct anisotropy in its optical, electronic, and mechanical properties. We use the non-equilibrium Green's function approach and the first-principles method to investigate the thermal conductance for single-layer black phosphorus in the ballistic transport regime, in which the phonon-phonon scattering is neglected. We find that the anisotropy in the thermal conduction is very weak for the single-layer black phosphorus--the difference between two in-plane directions is less than 4%. Our phonon calculations disclose that the out-of-plane acoustic phonon branch has lower group velocities in the direction perpendicular to the pucker, as the black phosphorus is softer in this direction, leading to a weakening effect for the thermal conductance in the perpendicular direction. However, the longitudinal acoustic phonon branch behaves abnormally; i.e., the group velocity of this phonon branch is higher in the perpendicular direction, although the single-layer black phosphorus is softer in this direction. The abnormal behavior of the longitudinal acoustic phonon branch is closely related to the highly anisotropic Poisson's ratio in the single-layer black phosphorus. As a result of the counteraction between the out-of-plane phonon mode and the in-plane phonon modes, the thermal conductance in the perpendicular direction is weaker than the parallel direction, but the anisotropy is pretty small. PMID:25571869

  10. Phosphorus and Nitrogen Regulate Arbuscular Mycorrhizal Symbiosis in Petunia hybrida

    PubMed Central

    Nouri, Eva; Breuillin-Sessoms, Florence; Feller, Urs; Reinhardt, Didier

    2014-01-01

    Phosphorus and nitrogen are essential nutrient elements that are needed by plants in large amounts. The arbuscular mycorrhizal symbiosis between plants and soil fungi improves phosphorus and nitrogen acquisition under limiting conditions. On the other hand, these nutrients influence root colonization by mycorrhizal fungi and symbiotic functioning. This represents a feedback mechanism that allows plants to control the fungal symbiont depending on nutrient requirements and supply. Elevated phosphorus supply has previously been shown to exert strong inhibition of arbuscular mycorrhizal development. Here, we address to what extent inhibition by phosphorus is influenced by other nutritional pathways in the interaction between Petunia hybrida and R. irregularis. We show that phosphorus and nitrogen are the major nutritional determinants of the interaction. Interestingly, the symbiosis-promoting effect of nitrogen starvation dominantly overruled the suppressive effect of high phosphorus nutrition onto arbuscular mycorrhiza, suggesting that plants promote the symbiosis as long as they are limited by one of the two major nutrients. Our results also show that in a given pair of symbiotic partners (Petunia hybrida and R. irregularis), the entire range from mutually symbiotic to parasitic can be observed depending on the nutritional conditions. Taken together, these results reveal complex nutritional feedback mechanisms in the control of root colonization by arbuscular mycorrhizal fungi. PMID:24608923

  11. Acute recumbency and marginal phosphorus deficiency in dairy cattle.

    PubMed

    Gerloff, B J; Swensen, E P

    1996-03-01

    Because of a mixing error at a local feed mill, a diet marginally deficient in phosphorus, compared with recommendation from the National Research Council, was fed to a high-producing dairy herd for 5 months. Two mature cows in early lactation became recumbent. Serum phosphorus concentration in 1 cow was low (1.8 mg/dl), but was not measured in the other cow. Ten other high-producing, first-lactation cows in the herd developed severe lameness. Results of analysis of rib bone samples from the recumbent cows were consistent with changes associated with demineralization. Bone ash, calcium, phosphorus, and magnesium concentrations were lower than published ranges for healthy cattle. Serum calcium, phosphorus, and magnesium concentrations in 8 unaffected cows were normal. For 6 unaffected cows, mean serum hydroxyproline concentration was higher during the period that the phosphorus-deficient diet was fed than when an adequate diet was fed. Moderate (15%) restrictions in dietary phosphorus intake, compared with National Research Council recommendations, can possibly result in health problems in high-producing dairy cattle. PMID:8617630

  12. Global phosphorus scarcity: identifying synergies for a sustainable future.

    PubMed

    Neset, Tina-Simone S; Cordell, Dana

    2012-01-15

    Global food production is dependent on constant inputs of phosphorus. In the current system this phosphorus is not predominantly derived from organic recycled waste, but to a large degree from phosphate-rock based mineral fertilisers. However, phosphate rock is a finite resource that cannot be manufactured. Our dependency therefore needs to be addressed from a sustainability perspective in order to ensure global food supplies for a growing global population. The situation is made more urgent by predictions that, for example, the consumption of resource intensive foods and the demand for biomass energy will increase. The scientific and societal debate has so far been focussed on the exact timing of peak phosphorus and on when the total depletion of the global reserves will occur. Even though the timing of these events is important, all dimensions of phosphorus scarcity need to be addressed in a manner which acknowledges linkages to other sustainable development challenges and which takes into consideration the synergies between different sustainability measures. Many sustainable phosphorus measures have positive impacts on other challenges; for example, shifting global diets to more plant-based foods would not only reduce global phosphorus consumption, but also reduce greenhouse gas emissions, reduce nitrogen fertiliser demand and reduce water consumption. PMID:21969145

  13. Calcium and phosphorus requirements of breeding bobwhite quail

    USGS Publications Warehouse

    DeWitt, J.B.; Nestler, R.B.; Derby, J.V., Jr.

    1949-01-01

    In the course of studies designed to determine the calcium and phosphorus requirements of breeding bobwhite quail, it was found that best results were obtained when the Ca/P ratio in the diet was approximately 2.3:1. Variations in the Ca/P ratio produced significant differences in results when the level of phosphorus in the diet was 0.75%, but the differences were less marked when the level of phosphorus was increased to 1.00%. Although diets containing 0.75% phosphorus and 1.8% calcium appeared adequate for reproduction, as judged by the criteria of the maintenance of satisfactory condition in the breeders, egg production, fertility, hatchability and survival of offspring during the first 5 days after hatching, it was found that the winter mortality of the offspring of birds fed such a diet was much greater than that occurring in the offspring of birds fed on diets containing 1.00 or 1.25% phosphorus. It is concluded that breeding bobwhite quail require diets furnishing approximately 1.00% phosphorus and 2.3% calcium.

  14. Local lattice distortion relating to phosphorus antisite defect in phosphorus-ion-implanted GaP layer

    Microsoft Academic Search

    K. Kuriyama; Takashi Kato; Satoru Tajima; Tomoharu Kato; Sin-Ichi Takeda

    1995-01-01

    The local lattice distortion relating to the phosphorus antisite defect (PGa) in the P+-ion-implanted GaP layer was studied using Rutherford backscattering (RBS), photoacoustic (PA), Raman scattering, and photoluminescence (PL) methods. The displacement fraction due to the excess phosphorus in 800 °C annealed samples is estimated to be ?2×1020\\/cm3 by RBS channeling measurements. The slight reduction of the LO-TO phonon frequency

  15. Effects of phosphorus application and mycorrhizal inoculation on root characteristics of subterranean clover and ryegrass in relation to phosphorus uptake

    Microsoft Academic Search

    N. S. Bolan; A. D. Robson; N. J. Barrow

    1987-01-01

    The effects of phosphorus (P) application and mycorrhizal inoculation on the root characteristics of subterranean clover and\\u000a ryegrass were examined. Phosphorus application increased total root length, root surface area and root volume of both plant\\u000a species. In contrast, mycorrhizal infection only affected the root characteristics of subterranean clover. Ryegrass took up\\u000a more P than non-mycorrhizal subterranean clover at all levels

  16. Phosphorus runoff from turfgrass as affected by phosphorus fertilization and clipping management.

    PubMed

    Bierman, Peter M; Horgan, Brian P; Rosen, Carl J; Hollman, Andrew B; Pagliari, Paulo H

    2010-01-01

    Phosphorus enrichment of surface water is a concern in many urban watersheds. A 3-yr study on a silt loam soil with 5% slope and high soil test P (27 mg kg(-1) Bray P1) was conducted to evaluate P fertilization and clipping management effects on P runoff from turfgrass (Poa pratensis L.) under frozen and nonfrozen conditions. Four fertilizer treatments were compared: (i) no fertilizer, (ii) nitrogen (N)+potassium (K)+0xP, (iii) N+K+1xP, and (iv) N+K+3xP. Phosphorus rates were 21.3 and 63.9 kg ha(-1) yr(-1) the first year and 7.1 and 21.3 kg ha(-1) yr(-1) the following 2 yr. Each fertilizer treatment was evaluated with clippings removed or clippings recycled back to the turf. In the first year, P runoff increased with increasing P rate and P losses were greater in runoff from frozen than nonfrozen soil. In year 2, total P runoff from the no fertilizer treatment was greater than from treatments receiving fertilizer. This was because reduced turf quality resulted in greater runoff depth from the no fertilizer treatment. In year 3, total P runoff from frozen soil and cumulative total P runoff increased with increasing P rate. Clipping management was not an important factor in any year, indicating that returning clippings does not significantly increase P runoff from turf. In the presence of N and K, P fertilization did not improve turf growth or quality in any year. Phosphorus runoff can be reduced by not applying P to high testing soils and avoiding fall applications when P is needed. PMID:20048316

  17. Quantum well intermixing of indium gallium arsenide(phosphorus)/indium phosphorus heterostructures

    NASA Astrophysics Data System (ADS)

    Haysom, Joan E.

    This thesis studies several aspects of the interdiffusion of InGaAs(P)/InP quantum well (QW) heterostructures, from the fundamental defect mechanisms, through optimization of processing parameters, to novel device applications. Conclusions from each of these areas have been drawn which further the scientific understanding and the manufacturability of the technique. The thermal stability of a series of different wafers is studied to highlight how poor quality of growth can cause increased interdiffusion, and to review the requirements for achieving repeatable annealing. Purposeful and controlled interdiffusion is accomplished through the introduction of excess defects into layers above the QWs, which during a subsequent anneal, diffuse through the QWs and enhance interdiffusion of atoms of the QWs with atoms of the barriers. These excess defects are introduced using two different techniques, via growth at low temperatures (LT) using chemical beam epitaxy (CBE), and via implantation of phosphorus ions. The CBE LT growth technique is new, and reported for the first time in this thesis. Characterization of the as-grown layers leads us to believe that they have an excess of phosphorus. The diffusion rate of the mobile defects which cause the intermixing is also measured, and the interdiffusion is shown to occur predominantly on the group-V sublattice. Due to many similarities between this and the results of the implantation technique, it is proposed that these mobile defects are the same for both intermixing approaches, and that the behaviour can be explained by a phosphorus interstitial mechanism. Annealing recipes for the implantation-induced technique are optimized, and the sample-to-sample reproducibility of the blueshift for this method was found to be quite good (standard deviations of ˜6 meV on blueshifts of ˜70 meV). The lateral selectivity and refractive index changes are characterized, and used in combination to create novel buried waveguide devices.

  18. X-33 Phase 2

    NASA Technical Reports Server (NTRS)

    1997-01-01

    In response to Clause 17 of the Cooperative Agreement NCC8-115, Lockheed Martin Skunk Works has compiled an Annual Performance Report of the X-33/RLV Program. This report consists of individual reports from all industry team members, as well as NASA team centers. Contract award was announced on July 2, 1996 and the first milestone was hand delivered to NASA MSFC on July 17, 1996. The first year has been one of growth and progress as all team members staffed up and embarked on the technical adventure of the 20th century... the ultimate goal . . a Single Stage to Orbit (SSTO) Reuseable Launch Vehicle (RLV).

  19. Phosphorus availability from inorganic phosphorus sources in yellowtail ( Seriola quinqueradiata Temminck and Schlegel)

    Microsoft Academic Search

    Pallab Kumer Sarker; Haruhisa Fukada; Toshiro Masumoto

    2009-01-01

    This study was conducted to select an appropriate inorganic phosphorus (P) source with higher P availability, judging from apparent availability of P and non-fecal P excretion, in yellowtail (270±44.6 g) fed five inorganic P sources. Albumin based purified diets with five inorganic P sources were used: potassium phosphate monobasic, KH2PO4; sodium phosphate monobasic, NaH2PO42H2O; calcium phosphate monobasic, Ca (H2PO4)2H2O; calcium phosphate

  20. Black phosphorus nanoelectromechanical resonators vibrating at very high frequencies

    NASA Astrophysics Data System (ADS)

    Wang, Zenghui; Jia, Hao; Zheng, Xuqian; Yang, Rui; Wang, Zefang; Ye, G. J.; Chen, X. H.; Shan, Jie; Feng, Philip X.-L.

    2014-12-01

    We report on the experimental demonstration of a new type of nanoelectromechanical resonator based on black phosphorus crystals. Facilitated by a highly efficient dry transfer technique, crystalline black phosphorus flakes are harnessed to enable drumhead resonators vibrating at high and very high frequencies (HF and VHF bands, up to ~100 MHz). We investigate the resonant vibrational responses from the black phosphorus crystals by devising both electrical and optical excitation schemes, in addition to measuring the undriven thermomechanical motions in these suspended nanostructures. Flakes with thicknesses from ~200 nm down to ~20 nm clearly exhibit elastic characteristics transitioning from the plate to the membrane regime. Both frequency- and time-domain measurements of the nanomechanical resonances show that very thin black phosphorus crystals hold interesting potential for moveable and vibratory devices and for semiconductor transducers where high-speed mechanical motions could be coupled to the attractive electronic and optoelectronic properties of black phosphorus.We report on the experimental demonstration of a new type of nanoelectromechanical resonator based on black phosphorus crystals. Facilitated by a highly efficient dry transfer technique, crystalline black phosphorus flakes are harnessed to enable drumhead resonators vibrating at high and very high frequencies (HF and VHF bands, up to ~100 MHz). We investigate the resonant vibrational responses from the black phosphorus crystals by devising both electrical and optical excitation schemes, in addition to measuring the undriven thermomechanical motions in these suspended nanostructures. Flakes with thicknesses from ~200 nm down to ~20 nm clearly exhibit elastic characteristics transitioning from the plate to the membrane regime. Both frequency- and time-domain measurements of the nanomechanical resonances show that very thin black phosphorus crystals hold interesting potential for moveable and vibratory devices and for semiconductor transducers where high-speed mechanical motions could be coupled to the attractive electronic and optoelectronic properties of black phosphorus. Electronic supplementary information (ESI) available: A supporting document with additional technical details is included as a separate PDF file. See DOI: 10.1039/c4nr04829f

  1. Chemical measurements of phosphorus avialability in some medium to fine textured soils

    E-print Network

    Velasco Molina, Hugo Alejo

    1956-01-01

    , and the phosphorus was determined periodically using three accepted methods oi' extraction. REVIEW OF LITERATURE Black (5), working with finely ground kaolinite, observed a maximum fixation of phosphorus at pH 3. 0 to 4. 0 regardless of the con- centration oi... FIGURES Ei'feet oi' time on the phosphorus extracted by 0. 5 M NaHC03 (mean of 5 soils and 6 phosphorus sources). . . , . . . . . . . 15 Effect of time on phosphorus extracted by 0. 5 M NaHC03 from 5 soils (average) treated with 6 phosphorus sources...

  2. Photometry of M33

    NASA Astrophysics Data System (ADS)

    Schlingman, W. M.; Massey, P.

    2003-12-01

    We present UBVRI photometry of stars in the nearby Local Group galaxy M33, obtained by imaging with the Kitt Peak 4-m telescope and MOSAIC camera as part of our Local Group Galaxies survey. To obtain this photometry, we have been developing and strengthening routines that can search through images and automatically photometer these stars using point-spread-function fitting. The routines split the image into its corresponding eight CCD chips and then do automated photometry on each chip separately, so that separate color transformations can be applied in a chip-by-chip manner. Our calibration data comes from images obtained on the Lowell 1.1-m Hall telescope on Anderson Mesa, obtained on numerous pristine photometric nights. Once calibrated, our Mosaic photometry values are averaged, and a complete catalogue of positions and photometry (with errors) is obtained. In the end, we have a list of several hundred thousand stars with magnitudes and colors. These data can be used to analyze the stellar populations in M33, one of our closest neighbors. We will briefly describe our procedure, and present the first HR diagrams from our data. This work has been supported by the NSF under grant AST0093060.

  3. Forms of organic phosphorus in wetland soils

    NASA Astrophysics Data System (ADS)

    Cheesman, A. W.; Turner, B. L.; Reddy, K. R.

    2014-12-01

    Phosphorus (P) cycling in freshwater wetlands is dominated by biological mechanisms, yet there has been no comprehensive examination of the forms of biogenic P (i.e., forms derived from biological activity) in wetland soils. We used solution 31P NMR spectroscopy to identify and quantify P forms in surface soils of 28 palustrine wetlands spanning a range of climatic, hydrogeomorphic, and vegetation types. Total P concentrations ranged between 51 and 3516 ?g P g-1, of which an average of 58% was extracted in a single-step NaOH-EDTA procedure. The extracts contained a broad range of P forms, including phosphomonoesters (averaging 24% of the total soil P), phosphodiesters (averaging 10% of total P), phosphonates (up to 4% of total P), and both pyrophosphate and long-chain polyphosphates (together averaging 6% of total P). Soil P composition was found to be dependant upon two key biogeochemical properties: organic matter content and pH. For example, stereoisomers of inositol hexakisphosphate were detected exclusively in acidic soils with high mineral content, while phosphonates were detected in soils from a broad range of vegetation and hydrogeomorphic types but only under acidic conditions. Conversely inorganic polyphosphates occurred in a broad range of wetland soils, and their abundance appears to reflect more broadly that of a "substantial" and presumably active microbial community with a significant relationship between total inorganic polyphosphates and microbial biomass P. We conclude that soil P composition varies markedly among freshwater wetlands but can be predicted by fundamental soil properties.

  4. Phosphorus: a limiting nutrient for humanity?

    PubMed

    Elser, James J

    2012-12-01

    Phosphorus is a chemical element that is essential to life because of its role in numerous key molecules, including DNA and RNA; indeed, organisms require large amounts of P to grow rapidly. However, the supply of P from the environment is often limiting to production, including to crops. Thus, large amounts of P are mined annually to produce fertilizer that is applied in support of the 'Green Revolution.' However, much of this fertilizer eventually ends up in rivers, lakes and oceans where it causes costly eutrophication. Furthermore, given increasing human population, expanding meat consumption, and proliferating bioenergy pressures, concerns have recently been raised about the long-term geological, economic, and geopolitical viability of mined P for fertilizer production. Together, these issues highlight the non-sustainable nature of current human P use. To achieve P sustainability, farms need to become more efficient in how they use P while society as a whole must develop technologies and practices to recycle P from the food chain. Such large-scale changes will probably require a radical restructuring of the entire food system, highlighting the need for prompt but sustained action. PMID:22465489

  5. Black phosphorus radio-frequency transistors.

    PubMed

    Wang, Han; Wang, Xiaomu; Xia, Fengnian; Wang, Luhao; Jiang, Hao; Xia, Qiangfei; Chin, Matthew L; Dubey, Madan; Han, Shu-jen

    2014-11-12

    Few-layer and thin film forms of layered black phosphorus (BP) have recently emerged as a promising material for applications in high performance nanoelectronics and infrared optoelectronics. Layered BP thin films offer a moderate bandgap of around 0.3 eV and high carrier mobility, which lead to transistors with decent on-off ratios and high on-state current densities. Here, we demonstrate the gigahertz frequency operation of BP field-effect transistors for the first time. The BP transistors demonstrated here show respectable current saturation with an on-off ratio that exceeds 2 × 10(3). We achieved a current density in excess of 270 mA/mm and DC transconductance above 180 mS/mm for hole conduction. Using standard high frequency characterization techniques, we measured a short-circuit current-gain cutoff frequency fT of 12 GHz and a maximum oscillation frequency fmax of 20 GHz in 300 nm channel length devices. BP devices may offer advantages over graphene transistors for high frequency electronics in terms of voltage and power gain due to the good current saturation properties arising from their finite bandgap, thus can be considered as a promising candidate for the future high performance thin film electronics technology for operation in the multi-GHz frequency range and beyond. PMID:25347787

  6. Hydrologic transport and partitioning of phosphorus fractions

    NASA Astrophysics Data System (ADS)

    Berretta, C.; Sansalone, J.

    2011-06-01

    SummaryPhosphorus (P) in rainfall-runoff partitions between dissolved and particulate matter (PM) bound phases. This study investigates the transport and partitioning of P to PM fractions in runoff from a landscaped and biogenically-loaded carpark in Gainesville, FL (GNV). Additionally, partitioning and concentration results are compared to a similarly-sized concrete-paved source area of a similar rainfall depth frequency distribution in Baton Rouge, LA (BTR), where in contrast vehicular traffic represents the main source of pollutants. Results illustrate that concentrations of P fractions (dissolved, suspended, settleable and sediment) for GNV are one to two orders of magnitude higher than BTR. Despite these differences the dissolved fraction ( f d) and partitioning coefficient ( K d) distributions are similar, illustrating that P is predominantly bound to PM fractions. Examining PM size fractions, specific capacity for P (PSC) indicates that the P concentration order is suspended > settleable > sediment for GNV, similarly to BTR. For GNV the dominant PM mass fraction is sediment (>75 ?m), while the mass of P is distributed predominantly between sediment and suspended (<25 ?m) fractions since these PM mass fractions dominated the settleable one. With respect to transport of PM and P fractions the predominance of events for both areas is mass-limited first-flush, although each fraction illustrated unique washoff parameters. However, while transport is predominantly mass-limited, the transport of each PM and P fraction is influenced by separate hydrologic parameters.

  7. The role of diet in phosphorus demand

    NASA Astrophysics Data System (ADS)

    Metson, Geneviève S.; Bennett, Elena M.; Elser, James J.

    2012-12-01

    Over the past 50 years, there have been major changes in human diets, including a global average increase in meat consumption and total calorie intake. We quantified how changes in annual per capita national average diets affected requirements for mined P between 1961 and 2007, starting with the per capita availability of a food crop or animal product and then determining the P needed to grow the product. The global per capita P footprint increased 38% over the 46 yr time period, but there was considerable variability among countries. Phosphorus footprints varied between 0.35 kg P capita-1 yr-1 (DPR Congo, 2007) and 7.64 kg P capita-1 yr-1 (Luxembourg, 2007). Temporal trends also differed among countries; for example, while China’s P footprint increased almost 400% between 1961 and 2007, the footprints of other countries, such as Canada, decreased. Meat consumption was the most important factor affecting P footprints; it accounted for 72% of the global average P footprint. Our results show that dietary shifts are an important component of the human amplification of the global P cycle. These dietary trends present an important challenge for sustainable P management.

  8. Phosphorus and nitrogen in coral reef sediments

    SciTech Connect

    Entsch, B.; Boto, K.G.; Sim, R.G.; Wellington, J.T.

    1983-05-01

    The occurrence of P and N in the sediments has been investigated on Davies Reef in the central region of the Great Barrier Reef Complex. Concentrations of inorganic P and N in the water were typical of nutrient-depleted tropical surface water. Carbonate sediments were found to contain a uniform pool of P (300 ppm by wt), principally in the form of inorganic phosphate. The interstitial water of the surface layer of sediment contained micromolar concentrations of inorganic P and even higher concentrations of inorganic N, principally as ammonium. These nutrient concentrations were considered too low to compete significantly with the uptake of available phasphate into algae. The presence of ammonium and soluble P was associated with anaerobic redox potentials in the sediments just below the surface. Soluble phosphorus was in equilibrium with a small, rapidly exchangeable fraction of the sedimentary pool of inorganic phosphate. Analyses of P in growing tips of Halimeda and corals (which supply more than half of reef sediments) suggested that the skeletons provide a biological mechanism for the replenishment of at least some of the sedimentary pool. Ratios of C:N:P for a selection of benthic algae were used as a preliminary indicator of thier N and P status.

  9. Expert systems guide biological phosphorus removal

    SciTech Connect

    Krichten, D.J.; Wilson, K.D.; Tracy, K.D. (Air Products and Chemicals, Inc., Allentown, PA (United States))

    1991-10-01

    There is a large body of knowledge regarding optimum control strategies for new secondary wastewater treatment technology using an anaerobic selector to provide biological phosphorus removal. However, because the selector technology is new and the concepts differ somewhat from those used in conventional activated sludge wastewater treatment, a method of communicating this knowledge to plant operators is needed. Traditional methods such as classroom training and operating manuals are of limited effectiveness. The commonplace availability and low cost of the personal computer (PC) makes it practical to use a computer program to communicate the type of information required to control a wastewater treatment plant. Knowledge-based systems technology, commonly referred to as expert systems (ES) technology, is easy to use, provides useful information regarding a consistent control strategy, relieves the anxiety associated with learning a new process,' and provides instruction for inexperienced personnel. ES technology does not require special formatted input and is therefore easily accessible. All information required by the program is readily available through routine laboratory analysis, common plant instrumentation, or direct user observation. The program was designed for all levels of computer users and will run on all IBM-compatible or Apple MacIntosh systems.

  10. Metagenomic analysis of phosphorus removing sludgecommunities

    SciTech Connect

    Garcia Martin, Hector; Ivanova, Natalia; Kunin, Victor; Warnecke,Falk; Barry, Kerrie; McHardy, Alice C.; Yeates, Christine; He, Shaomei; Salamov, Asaf; Szeto, Ernest; Dalin, Eileen; Putnam, Nik; Shapiro, HarrisJ.; Pangilinan, Jasmyn L.; Rigoutsos, Isidore; Kyrpides, Nikos C.; Blackall, Linda Louise; McMahon, Katherine D.; Hugenholtz, Philip

    2006-02-01

    Enhanced Biological Phosphorus Removal (EBPR) is not wellunderstood at the metabolic level despite being one of the best-studiedmicrobially-mediated industrial processes due to its ecological andeconomic relevance. Here we present a metagenomic analysis of twolab-scale EBPR sludges dominated by the uncultured bacterium, "CandidatusAccumulibacter phosphatis." This analysis resolves several controversiesin EBPR metabolic models and provides hypotheses explaining the dominanceof A. phosphatis in this habitat, its lifestyle outside EBPR and probablecultivation requirements. Comparison of the same species from differentEBPR sludges highlights recent evolutionary dynamics in the A. phosphatisgenome that could be linked to mechanisms for environmental adaptation.In spite of an apparent lack of phylogenetic overlap in the flankingcommunities of the two sludges studied, common functional themes werefound, at least one of them complementary to the inferred metabolism ofthe dominant organism. The present study provides a much-needed blueprintfor a systems-level understanding of EBPR and illustrates thatmetagenomics enables detailed, often novel, insights into evenwell-studied biological systems.

  11. Agronomic phosphorus imbalances across the world's croplands

    PubMed Central

    MacDonald, Graham K.; Bennett, Elena M.; Potter, Philip A.; Ramankutty, Navin

    2011-01-01

    Increased phosphorus (P) fertilizer use and livestock production has fundamentally altered the global P cycle. We calculated spatially explicit P balances for cropland soils at 0.5° resolution based on the principal agronomic P inputs and outputs associated with production of 123 crops globally for the year 2000. Although agronomic inputs of P fertilizer (14.2 Tg of P·y?1) and manure (9.6 Tg of P·y?1) collectively exceeded P removal by harvested crops (12.3 Tg of P·y?1) at the global scale, P deficits covered almost 30% of the global cropland area. There was massive variation in the magnitudes of these P imbalances across most regions, particularly Europe and South America. High P fertilizer application relative to crop P use resulted in a greater proportion of the intense P surpluses (>13 kg of P·ha?1·y?1) globally than manure P application. High P fertilizer application was also typically associated with areas of relatively low P-use efficiency. Although manure was an important driver of P surpluses in some locations with high livestock densities, P deficits were common in areas producing forage crops used as livestock feed. Resolving agronomic P imbalances may be possible with more efficient use of P fertilizers and more effective recycling of manure P. Such reforms are needed to increase global agricultural productivity while maintaining or improving freshwater quality. PMID:21282605

  12. Characterisation of road sediments near Bordeaux with emphasis on phosphorus.

    PubMed

    Durand, Cédric; Ruban, Véronique; Amblès, André; Clozel, Blandine; Achard, Loïc

    2003-06-01

    Road sediments from the region of Bordeaux (France) were analysed for trace metals, hydrocarbons (including Polycyclic Aromatic Hydrocarbons, PAHs) and phosphorus. The aim of the study was to assess their potential risk for the environment. The sediments were collected by means of a sweeper. The particles are mostly sandy clay loam and silty clay loam with 5.6-8.3% CaO. Heavy metal concentrations are generally below the French and Dutch standards for polluted soils, but a few samples have higher concentrations, e.g., 547 mg kg(-1) for Zn, and 222 mg kg(-1) for Pb. PAH concentrations are above the Dutch target value for polluted soils, and could be a threat to the environment: pyrene (2600 microg kg(-1)) and fluoranthene (1400 microg kg(-1)) have the highest concentrations, whereas chrysene (340 microg kg(-1)) has the lowest. Consequently, these sediments must be considered as waste according to the French circular no 2001-39 from 18 June 2001 and cannot be disposed of anywhere. The Standards Measurements and Testing (SMT) protocol for sequential extraction of phosphorus in sediments was used to determine the forms of phosphorus in the samples. Total phosphorus concentration is 620 mg kg(-1) on average, with a maximum of 933 mg kg(-1); organic phosphorus content is low (36 mg kg(-1) on average). The protocol could be slightly amended, especially with regards to organic phosphorus at low concentrations and could then be used for the determination of phosphorus in other materials such as sludge from detention ponds. PMID:12833990

  13. The "phosphorus pyramid": a visual tool for dietary phosphate management in dialysis and CKD patients.

    PubMed

    D'Alessandro, Claudia; Piccoli, Giorgina B; Cupisti, Adamasco

    2015-01-01

    Phosphorus retention plays a pivotal role in the onset of mineral and bone disorders (MBD) in chronic kidney disease (CKD). Phosphorus retention commonly occurs as a result of net intestinal absorption exceeding renal excretion or dialysis removal. The dietary phosphorus load is crucial since the early stages of CKD, throughout the whole course of the disease, up to dialysis-dependent end-stage renal disease.Agreement exits regarding the need for dietary phosphate control, but it is quite challenging in the real-life setting. Effective strategies to control dietary phosphorus intake include restricting phosphorus-rich foods, preferring phosphorus sourced from plant origin, boiling as the preferred cooking procedure and avoiding foods with phosphorus-containing additives. Nutritional education is crucial in this regard.Based on the existing literature, we developed the "phosphorus pyramid", namely a novel, visual, user-friendly tool for the nutritional education of patients and health-care professionals. The pyramid consists of six levels in which foods are arranged on the basis of their phosphorus content, phosphorus to protein ratio and phosphorus bioavailability. Each has a colored edge (from green to red) that corresponds to recommended intake frequency, ranging from "unrestricted" to "avoid as much as possible".The aim of the phosphorus pyramid is to support dietary counseling in order to reduce the phosphorus load, a crucial aspect of integrated CKD-MBD management. PMID:25603926

  14. Temperature dependent phonon shifts in few-layer black phosphorus.

    PubMed

    Late, Dattatray J

    2015-03-18

    Atomically thin two-dimensional (2D) sheets of black phosphorus have attracted much attention due to their potential for future nanoelectronic and photonics device applications. Present investigations deal with the temperature dependent phonon shifts in a few-layer black phosphorus nanosheet sample prepared using micromechanical exfoliation on a 300 nm SiO2/Si substrate. The temperature dependent Raman spectroscopy experiments were carried out on a few-layer black phosphorus sample, which depicts softening of Ag(1), B2g, and Ag(2) modes as temperature increases from 77 to 673 K. The calculated temperature coefficients for Ag(1), B2g, and Ag(2) modes of the few-layer black phosphorus nanosheet sample were observed to be -0.01, -0.013, and -0.014 cm(-1) K(-1), respectively. The temperature dependent softening modes of black phosphorus results were explained on the basis of a double resonance process which is more active in an atomically thin sample. This process can also be fundamentally pertinent in other promising and emerging 2D ultrathin layer and heterostructured materials. PMID:25730146

  15. Phosphorus Recovery Using Zirconium-Loaded Saponified Orange Juice Residue

    NASA Astrophysics Data System (ADS)

    Harada, Hiroyuki; Kondo, Mitsunori; Biswas, Biplob K.; Ohura, Seichirou; Inoue, Katsutoshi; Ishikawa, Susumu; Kawakita, Hidetaka; Ohto, Keisuke

    Zirconium was immobilized to orange juice residue, to investigate the feasibility of using zirconium-loaded saponified orange juice residue (Zr-SOJR) for phosphorus recovery from secondary effluent and the extraction solution from incinerated sewage sludge ash by using H2SO4 and HCl. These had phosphorus concentrations of 68.2 mg/dm3 and 5.9 mg/dm3, respectively. The phosphorus removal rate secondary effluent increased with an increasing solid/liquid ratio in batch experiments. The adsorption capacity of Zr-SOJR was also compared with those obtained using a synthetic phosphorus solution and using zirconium-loaded ferrite. The prepared absorbent was effective for phosphorus removal and exhibited a reasonably high sorption capacity, twice that of zirconium ferrite. Secondary effluent was treated by packed column, and this reached break-through after 300 bed volumes. The results from phosphorous extraction from the ash indicate that can be treated with acid to efficiently recover phosphorous and thus can be absorbed by Zr-SOJR.

  16. Phosphorus recovery from municipal solid waste incineration fly ash.

    PubMed

    Kalmykova, Yuliya; Fedje, K Karlfeldt

    2013-06-01

    The potential of phosphorus (P) recycling from municipal solid waste incineration (MSWI) residue is investigated. Vast and ever increasing amounts of incineration residues are produced worldwide; these are an environmental burden, but also a resource, as they are a major sink for the material flows of society. Due to strict environmental regulations, in combination with decreasing landfilling space, the disposal of the MSWI residues is problematic. At the same time, resource scarcity is recognized as a global challenge for the modern world, and even more so for future generations. This paper reports on the methods and efficiency of P extraction from MSWI fly ash by acid and base leaching and precipitation procedures. Phosphorus extracted from the MSWI residues generated each year could meet 30% of the annual demand for mineral phosphorus fertiliser in Sweden, given a recovery rate of 70% achieved in this initial test. The phosphorus content of the obtained product is slightly higher than in sewage sludge, but due to the trace metal content it is not acceptable for application to agricultural land in Sweden, whereas application in the rest of the EU would be possible. However, it would be preferable to use the product as a raw material to replace rock phosphate in fertilizer production. Further development is currently underway in relation to procedure optimization, purification of the phosphorus product, and the simultaneous recovery of other resources. PMID:23490361

  17. The supplementation of phytase RONOZYME® P on the growth and the utilisation of phosphorus by sex-reversed red tilapia (Oreochromis niloticus Linn.)

    Microsoft Academic Search

    Jirawat Tudkaew; Jacques Gabaudan; Wutiporn Phromkunthong

    The effect of phytase supplementation to a low fish meal based diet on growth performance and phosphorus utilis- ation was investigated in sex-reversed red tilapia. Diets were prepared without phytase or inorganic phosphorus supplement- ation, with phytase, with supplemented inorganic phosphorus and with both phytase and supplemental inorganic phosphorus. Available phosphorus was set below requirement and the total phosphorus set

  18. Pyromineralization of soil phosphorus in savanna ecosystems

    NASA Astrophysics Data System (ADS)

    Hartshorn, A.; Coetsee, C.; Chadwick, O.

    2007-12-01

    The weathering of rock supplies phosphorus (P) to ecosystems. Phosphorus limitation of ecosystems can be severe in thicker or older soils, where soil production rates from rock and therefore release of P is slower than in thinner or younger soils. Limitation may be especially pronounced in drier ecosystems that are experiencing increasing N deposition. Our savanna field sites in Kruger National Park, South Africa meet all three of these criteria: soil residence times average 250 ky, the climate is semiarid, and N inputs average 20 kg ha-1 y-1. Not all soil P is plant-available, and because our field sites experience occasional fires, our objectives were to quantify the importance of pyromineralization of soil P, the transfer by fire of soil P from recalcitrant to labile (HCO3- extractable) pools. We quantified these soil P pools using a modified Hedley scheme (an array of chemical extractants). Three sets of soils were fractionated: 1. soils from 10 profiles along an intensively studied hillslope, bracketing a pronounced structural and functional ecotone; 2. surface soils from these 10 profiles after a simulated burn; and 3. surface soils from the Shabeni Experimental Plots, where 4 fire treatments have been maintained for decades: no fire, annual fire in the dry season, triennial fire in the dry season, and triennial fire in the wet season. Total P for hillslope soils ranged from 45 to 135 g m-2 (to 50 cm depth) and from 8 to 15 g m-2 (to 5 cm depth). Total soil P was lowest in midslope soils, where upslope sandy soils dominated by broad-leafed vegetation shift abruptly to downslope clayey soils with fine-leafed vegetation. Simulated fire for the hillslope soils reduced total P slightly, but boosted labile P by 1.7 g m-2 (to 5 cm), representing 17% of total P in the surface 5 cm. This pyromineralization effect was not uniform across the hillslope: downslope soils gained about 50% more labile P than midslope soils with simulated burning. With a fire return interval of 4 years, pyromineralization produces a flux of P into plant-available pools of +0.4 g m-2 y-1, a flux that approximates plant uptake of labile P based on foliar P. We observed the same general patterns for soils burnt triennially in the wet season. There, the difference in labile P was greatest between treatment and control plots (10 ug g-1 or 0.9 g m-2 to 5 cm depth), producing a flux of labile P of +0.3 g m-2 y-1. Soils from the other two fire treatments contained less labile P than the control plot, with the most pronounced deficit (-0.25 g m-2 to 5 cm) for the plots burnt triennially in the dry season. Infrequent, high severity fires may prevent the incorporation of biomass P into soils, eliminating the opportunity for pyromineralization of recalcitrant P. These fire-mediated transfers from recalcitrant to labile P pools are nearly 1000 times greater than our estimated flux from rock to soil of total P (0.0008 g P2O5 m-2 y-1). These patterns suggest that pyromineralization represents a significant input of labile P to these P-limited ecosystems, where low chemical weathering rates lead to intense cycling of rock-derived nutrients.

  19. Phosphorus Dynamic and Water Quality Paradigm. (Invited)

    NASA Astrophysics Data System (ADS)

    Pant, H. K.

    2009-12-01

    Depending on environmental conditions, stored nutrients and contaminants could be released from organic matrix through mineralization, and recycled within or exported from the ecosystems. The rates and duration of organic matter accumulations under changing hydro-climatic conditions are critical determinants of how a freshwater system functions as an ecological unit within a landscape. Aquatic ecosystems such as freshwaters can be very sensitive to changes, e.g., water quality, quantity and temperature, induced by climatic changes. Phosphorus (P) influx in freshwater systems may occur as a byproduct of single or many activities such as urban development and/or loading from within the systems due to gradual or sudden changes in environmental conditions. Any direct or indirect alterations due to anthropogenic influences, including a global rise in temperature, pose a serious threat of accelerated eutrophication of freshwater systems mainly due to P loading, causing their ultimate destructions. Our studies showed that sediments/soils contain both organic P (e.g., sugar phosphates and nucleoside monophosphates) and inorganic P in significant proportions, as well as acquiring data on P sorption phenomena, phosphatase-induced hydrolysis along with relative composition of various P forms will be helpful to derive P Destabilization Index to aid to the freshwater ecosystem management. It is indicative that any mitigating strategies need to take into account the nonlinear behaviors of the ecosystem processes and components, and begin planning to minimize effects of the changes. Also, it is crucial to be ready to integrate if there may need of policy revisions or adoption of new approaches and technologies, as the ecosystem struggles to attain a new equilibrium.

  20. Use of reactive materials to bind phosphorus.

    PubMed

    Chardon, Wim J; Groenenberg, Jan E; Temminghoff, Erwin J M; Koopmans, Gerwin F

    2012-01-01

    Phosphorus (P) losses from agricultural soils have caused surface water quality impairment in many regions of the world, including The Netherlands. Due to the large amounts of P accumulated in Dutch soils, the generic fertilizer and manure policy will not be sufficient to reach in time the surface water quality standards of the European Water Framework Directive. Additional measures must be considered to further reduce P enrichment of surface waters. One option is to immobilize P in soils or manure or to trap P when it moves through the landscape by using reactive materials with a large capacity to retain P. We characterized and tested two byproducts of the process of purification of deep groundwater for drinking water that could be used as reactive materials: iron sludge and iron-coated sand. Both materials contain low amounts of inorganic contaminants, which also have a low (bio)availability, and bound a large amount of P. We could describe sorption of P to the iron sludge in batch experiments well with the kinetic Freundlich equation (Q = × t (m) × C(n)). Kinetics had a large influence on P sorption in batch and column experiments and should be taken into account when iron-containing materials are tested for their capability to immobilize or trap P. A negative aspect of the iron sludge is its low hydraulic conductivity; even when mixed with pure sand to a mixture containing 20% sludge, the conductivity was very low, and only 10% sludge may be needed before application is possible in filters or barriers for removing P from groundwater. Due to its much higher hydraulic conductivity, iron-coated sand has greater potential for use under field conditions. Immobilizing P could be an option for using iron sludge as a reactive material. PMID:22565245

  1. Phosphorus dynamics within agricultural drainage ditches in the lower Mississippi Alluvial Valley

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Excessive phosphorus loading from fertilizers in agriculture results in enriched runoff and downstream freshwater and saltwater aquatic system eutrophication. This study evaluated phosphorus dynamics in agricultural drainage ditches across eight sites within the Lower Mississippi Alluvial Valley (LM...

  2. HANDBOOK: RETROFITTING POTWS FOR PHOSPHORUS REMOVAL IN THE CHESAPEAKE BAY DRAINAGE BASIN

    EPA Science Inventory

    This document assesses the technology, economics, and efficiency of phosphorus removal processes for use in the Chesapeake Bay Drainage basin (CBDB). ince phosphorus removal requirements in the CBDB vary widely with geographic location, this document discusses the feasibility of ...

  3. Making Photosynthetic Biofuel Renewable: Recovering Phosphorus from Residual Biomass J. M. Gifford and P. Westerhoff

    E-print Network

    Hall, Sharon J.

    Making Photosynthetic Biofuel Renewable: Recovering Phosphorus from Residual Biomass J. M. Gifford to global warming. Biofuel from phototrophic microbes like algae and bacteria provides a viable substitute improves biofuel sustainability by refining phosphorus recycling. Biomass Production Residual Biomass

  4. Phosphorus transport by surface and subsurface flow pathways in an upland agricultural watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improved understanding of phosphorus transport by surface and subsurface flow pathways is critical to protecting water quality in agricultural watersheds. While considerable attention has been devoted to understanding phosphorus losses in overland flow, comparatively limited research has examined ph...

  5. Long-term controls on ocean phosphorus and oxygen in a global biogeochemical model

    Microsoft Academic Search

    V. Palastanga; C. P. Slomp; C. Heinze

    2011-01-01

    Sedimentary phosphorus dynamics are included in a global biogeochemical modelIncreases in phosphorus river inputs promote the expansion of ocean suboxiaPreferential P regeneration enhances the expansion of ocean suboxia

  6. The use of spectroscopic techniques (especially phosphorus-31 nuclear magnetic resonance [31

    E-print Network

    Sparks, Donald L.

    1617 The use of spectroscopic techniques (especially phosphorus-31 nuclear magnetic resonance [31 P; Shober et al., 2006; Toor et al., 2005a, 2005b) and solid-state phosphorus-31 nuclear magnetic resonance

  7. Morphological response of forage chicory fine roots to manipulated soil phosphorus levels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Appalachian pastures suffer multiple stresses that result in reduced yields. Chicory offers the potential for increased phosphorus uptake, reduced drought stress and anthelmintic secondary products. To study the mechanism of improved phosphorus uptake, an experiment with three cultivars, two Appal...

  8. Recent Changes in Soil Total Phosphorus in the Everglades: Water Conservation Area 3

    E-print Network

    Grunwald, Sabine

    Recent Changes in Soil Total Phosphorus in the Everglades: Water Conservation Area 3 Gregory L nutrient loading from drained agricul- tural lands, annual phosphorus (P) inputs to the Water Conservation

  9. Distribution of Phosphorus and Potassium Following Surface Banding of Fertilizer in Conservation Tillage Systems

    E-print Network

    Kovar, John L; Bortolon, Leandro; Karlen, Douglas L

    2009-01-01

    phosphorus distribution and sorption in starter fertilizerSoil Phosphorus Movement of available fertilizer P into thephosphorus determined via anion exchange resin membranes in six soil layers following surface band application of liquid fertilizer.

  10. Microbial and metabolic characterization of a denitrifying phosphorus-uptake/side stream phosphorus removal system for treating domestic sewage.

    PubMed

    Jin, Zhan; Ji, Fang-Ying; Xu, Xuan; Xu, Xiao-Yi; Chen, Qing-Kong; Li, Qi

    2014-11-01

    In this study, an advanced wastewater treatment process, the denitrifying phosphorus/side stream phosphorus removal system (DPR-Phostrip), was developed for the purpose of enhancing denitrifying phosphorus removal. The enrichment of denitrifying phosphorus-accumulating organisms (DPAOs) and the microbial community structure of DPR-Phostrip were evaluated by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), and the metabolic activity of seed sludge and activated sludge collected after 55 days of operation were evaluated by Biolog™ analysis. This experimental study of DPR-Phostrip operation showed that nutrients were removed effectively, and denitrifying phosphorus removal was observed during the pre-anoxic period. PCR-DGGE analysis indicated that DPR-Phostrip supported DPAO growth while inhibiting PAOs and GAOs. The major dominant species in DPR-Phostrip were Bacteroidetes bacterium, Saprospiraceae bacterium, and Chloroflexi bacterium. Moreover, the functional diversity indices calculated on the basis of Biolog analysis indicated that DPR-Phostrip had almost no effect on microbial community diversity but was associated with a shift in the dominant species, which confirms the results of the PCR-DGGE analysis. The results for average well color development, calculated via Biolog analysis, showed that DPR-Phostrip had a little impact on the metabolic activity of sludge. Further principal component analysis suggested that the ability to utilize low-molecular-weight organic compounds was reduced in DPR-Phostrip. PMID:25073616

  11. Phosphorus in Bottom Sediments of Pomeranian Bay (Southern Baltic—Poland)

    NASA Astrophysics Data System (ADS)

    Frankowski, L.; Bola?ek, J.; Szostek, A.

    2002-06-01

    The paper presents the results of determination of inorganic and organic forms of phosphorus in bottom sediments of Pomeranian Bay. The sediments were collected in March and July of 1996. The following characteristics of the sediments were determined: organic matter content, forms of inorganic phosphorus: loosely adsorbed phosphorus and phosphorus bound to aluminium, calcium and iron, as well as total inorganic phosphorus. Pomeranian Bay is a shallow basin, with depth averaging between 12 and 15 m and sandy sediments prevailing. Smaller silt fractions occur only in the vicinity of the ?wina River estuary and in deeper northern regions of the Bay. Calcium-bound phosphorus is the dominant form of inorganic phosphorus in the Pomeranian Bay. Iron-bound phosphorus is the second most prevailing form, and aluminium-bound phosphorus the third. Loosely bound phosphorus was present in the lowest amounts. Total inorganic phosphorus in the Bay consisted of the four forms listed above, except in estuarine regions where an additional form of phosphorus occurred, most probably occluded phosphorus. High organic phosphorus concentrations were found at the ?wina River estuary and in the northern part of the Bay (Saßnitz Deep) corresponding to the higher organic matter content of these sediments. Sediments of Pomeranian Bay contained less phosphorus than those from the Gulf of Gda?sk or Puck Bay and other parts of the Baltic Sea, suggesting that the amount of phosphorus in the sediments was determined by a number of inter-related factors, such as sediment type, amount of organic matter, the chemical composition of the sediment and oxygen content of near-bottom water.

  12. Nitrogen versus phosphorus-limited growth and sources of nutrients for coral reef macroalgae

    Microsoft Academic Search

    S. T. Larned

    1998-01-01

    Recent investigations of nutrient-limited productivity in coral reef macroalgae have led to the conclusion that phosphorus,\\u000a rather than nitrogen, is the primary limiting nutrient. In this study, comparison of the dissolved inorganic nitrogen:phosphorus\\u000a ratio in the water column of Kaneohe Bay, Hawaii, with tissue nitrogen:phosphorus ratios in macroalgae from Kaneohe Bay suggested\\u000a that nitrogen, rather than phosphorus, generally limits productivity

  13. Interrelationship between phosphorus, sodium, and chloride in the diet of laying hens.

    PubMed

    Junqueira, O M; Miles, R D; Harms, R H

    1984-06-01

    Two experiments were conducted with commercial egg production type hens to determine the effects of dietary phosphorus, sodium, and chloride levels as related to levels of plasma calcium and phosphorus, blood acid-base balance, and production characteristics. Sodium and chloride were supplied to the diet as sodium bicarbonate and hydrochloric acid, respectively. In Experiment 1, five treatment groups were fed diets ad libitum containing .2, .6, 1.0, 1.4, and 1.8% total phosphorus. The remaining treatment group was fed a diet containing .4% total phosphorus from 1400 to 2030 hr and 1.4% total phosphorus from 600 to 1100 hr. In Experiment 2, a 3 X 4 factorial arrangement of treatments was used that consisted of three levels of total phosphorus (.2, .6, and 1.4%) and four levels of added sodium (0, .06, .22, and .45%) provided by sodium bicarbonate. Three other treatment groups were fed diets containing .36% supplemental chloride supplied by hydrochloric acid and either .2, .6, or 1.4% total phosphorus. Egg production was decreased in hens fed diets containing 1.8% total phosphorus. Egg specific gravity was decreased by both low and high phosphorus levels. Hens fed .4% total phosphorus in the afternoon produced eggs with higher specific gravity as compared with hens fed 1.4% total phosphorus during the entire experiment. At 1.4% dietary phosphorus, a significant increase in specific gravity was observed when .2 or .8% sodium bicarbonate was added to the diet. Increasing dietary phosphorus resulted in elevated plasma phosphorus and calcium concentration. Plasma phosphorus of hens fed .2 through 1.8% total phosphorus declined slowly from oviposition until 6 hr after oviposition and then reached a peak at 21 hr after oviposition.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:6330717

  14. Phosphorus in the young supernova remnant Cassiopeia A.

    PubMed

    Koo, Bon-Chul; Lee, Yong-Hyun; Moon, Dae-Sik; Yoon, Sung-Chul; Raymond, John C

    2013-12-13

    Phosphorus ((31)P), which is essential for life, is thought to be synthesized in massive stars and dispersed into interstellar space when these stars explode as supernovae (SNe). Here, we report on near-infrared spectroscopic observations of the young SN remnant Cassiopeia A, which show that the abundance ratio of phosphorus to the major nucleosynthetic product iron ((56)Fe) in SN material is up to 100 times the average ratio of the Milky Way, confirming that phosphorus is produced in SNe. The observed range is compatible with predictions from SN nucleosynthetic models but not with the scenario in which the chemical elements in the inner SN layers are completely mixed by hydrodynamic instabilities during the explosion. PMID:24337291

  15. Phosphorus: The Noose of Sustainability and Renewability in Steelmaking

    NASA Astrophysics Data System (ADS)

    Tayeb, Mohammed A.; Spooner, Stephen; Sridhar, Seetharaman

    2014-09-01

    With rising ore prices and the continued demand for higher quality steels, much work has been carried out into refining and control prospects of steel chemistry. As several technologies around the world are exploring the control of phosphorus with high priority, an overview of current knowledge, ongoing research, and specific interest areas is presented. The reliance of the basic oxygen furnace steelmaking on iron ore quality is considered with regard to impurity levels, as well as the phosphorus content of direct reduced iron introduction to the electric arc furnace process. This article reviews methods to control phosphorus in steelmaking and proposes a practical approach based on laboratory-scale equilibrium experiments. The article ends by exploring energy savings in steelmaking as well as speculating on further avenues of steel production profitability.

  16. Recovery of phosphates from elemental phosphorus bearing wastes

    SciTech Connect

    Edwards, R.E.; Moore, O.E.; Sullivan, J.M.

    1994-10-01

    A process for oxidizing aqueous elemental phosphorus containing residues (sludges) to produce orthophosphate containing slurries suitable for subsequent reaction with ammonia to produce nitrogen and phosphate containing fertilizer products is presented. It comprises reacting aqueous elemental phosphorus containing residues with certain special mixtures of concentrated nitric acid and sulfuric acid to effect the conversion of the elemental phosphorus into mostly orthophosphoric acid and very little orthophosphorus acid with the relative ratios of the two acids being dependent upon the mole ratio of H{sub 2}SO{sub 4}:HNO{sub 3} employed in the processing. The resulting aqueous reaction intermediate is neutralized with ammonia during processing to a fluid or solid fertilizer product. Prior to the conversion to products, the aqueous reaction intermediate may be subjected to a solids separation step to remove insoluble salts of certain environmentally undesirable metals, such as Pb, Cd, Ba, and Cr.

  17. Method for processing wastes resulting from production of phosphorus

    SciTech Connect

    Alzhanov, T.M.; Bykov, V.I.; Chernogorenko, V.B.; Dmitrenko, V.V.; Ishkhanov, E.S.; Kipchakbaev, A.D.; Koverya, V.M.; Lynchak, K.A.; Markovsky, E.A.; Muchnik, S.V.; Pobortsev, M.E.; Sapian, V.G.; Sergienko, V.Y.; Vopilov, A.N.

    1980-03-11

    The method comprises processing slime and off-gases resulting from the production of phosphorus with an aqueous solution of copper sulphate having a concentration of from 15 to 50% at a temperature within the range of from 20* to 80* C. As a result, two products are obtained, i.e., a liquid product and a solid one. The solid product containing mainly copper phosphide as well as fluorides and chlorides of alkali metals and silicon, and silicates of calcium and aluminum, is used as a modifying and refining agent for hypereutectic silumines and for the manufacture of a copper-phosphorus alloy. The liquid product containing phosphoric acid, sulphuric acid and copper sulphate is used as starting product for the preparation of a copper-containing fertilizer. The method according to the present invention makes it possible to modify the production of phosphorus so as to eliminate the formation of secondary wastes and improve the environmental control.

  18. [Study on the nitrogen and phosphorus uptake ability of four plants cultivated on floating-bed].

    PubMed

    Wu, Jian-Qiang; Wang, Min; Wu, Jian; Jiang, Yue; Sun, Cong-Jun; Cao, Yong

    2011-04-01

    Plant floating-bed tested engineering was constructed for eutrophication control in Dian-shan Lake, the characteristics and nutrient uptake abilities of Canna indica, Iris pseudacorus, Thalia dealbata and Lythrum salicaria were compared. It shows that using upper and lower nylon nets to fix the plants on the floating-bed is beneficial for them to grow and reproduce rapidly. Survival rates of Canna indica, lris pseudacorus, Thalia dealbata and Lythrum salicaria are 83.33%, 83.33%, 76.67% and 53.33% respectively. Ramets of Canna indica and Thalia dealbata are 64 and 78 respectively in November, and the biomass (fresh weight) of these two plants are 32.0 and 38.6 kg per individual plant. Nitrogen (N) and phosphorus (P) content in stems/leaves of Canna indica and Thalia dealbata are greater than those in roots. The ratio between stems/leaves and roots of N, P content in Canna indica are 1.40 and 1.21 respectively, while 1.59 and 1.08 in Thalia dealbata. The difference of cumulative N, P content in plants is mostly on account of different plant biomass. N uptake ability of Thalia dealbata is the highest, which is 457.11 g per square; Canna indica has the highest P uptake ability, which is 41.29 g per square. N, P uptake ability of stems/leaves in Canna indica are 2.17 and 1.86 times higher than that of roots, while 1.73 and 1.17 times higher respectively in Thalia dealbata. Thus, Canna indica and Thalia dealbata are recommended as the floating-bed plants to control the eutrophication in Dian-shan Lake. PMID:21717738

  19. Spatial and temporal variability in excessive soil phosphorus levels in eastern North Carolina

    Microsoft Academic Search

    L. B. Cahoon; S. H. Ensign

    2004-01-01

    Numerous studies have shown that accumulation of excessive soil phosphorus raises the potential for phosphorus export and eutrophication of adjacent surface waters. Soil phosphorus data from the North Carolina Agronomy Division's database were analyzed for two-year periods spanning the decades of the 1980s and 1990s for 39 eastern North Carolina counties. Eastern North Carolina supported extensive row crop agriculture, rapidly

  20. A Phosphorus Budget, Model, and Load Reduction Strategy For Lake Champlain

    Microsoft Academic Search

    Eric Smeltzer; Scott Quinn

    1996-01-01

    A phosphorus budget and mass balance model were developed for Lake Champlain in order to identify load reductions necessary to attain interim in-lake total phosphorus concentration criteria established in a water quality agreement between New York, Quebec, and Vermont Total phosphorus loadings were measured from 31 tributaries, 88 wastewater discharges, and direct precipitation. Mean annual tributary loadings were estimated using

  1. Land Application of Wastes: An Educational Program. Phosphorus Considerations - Module 19, Objectives, and Script.

    ERIC Educational Resources Information Center

    Clarkson, W. W.; And Others

    The treatment of wastewater phosphorus via land application includes both chemical and biological mechanisms. Chemically, phosphorus reacts with iron, aluminum, and calcium compounds in the soil providing efficient removal over a wide range of pH values. Phosphorus is also absorbed by rooted plants which, upon harvest, constitute a further removal…

  2. Calcium Carbonate as Active Barrier Component for the Reten- tion of Phosphorus in Sediments

    Microsoft Academic Search

    U. Berg; D. Donnert; P. G. Weidler; A. Ehbrecht; M. Reinhardt

    Phosphorus release from anoxic sediments favours the growth of toxine producing blue- green algae. To prevent this internal fertilisation of lakes, the potential of active barrier systems (ABS) on eutrophicated lake sediments was investigated using calcium carbo- nate (CaCO3 = calcite) as a chemically active component. The interaction between cal- cite and phosphorus leads to an immobilisation of phosphorus. But,

  3. Dietary phosphorus excess: a risk factor in chronic bone, kidney, and cardiovascular disease?

    PubMed

    Uribarri, Jaime; Calvo, Mona S

    2013-01-01

    There is growing evidence in the nephrology literature supporting the deleterious health effect of excess dietary phosphorus intake. This issue has largely escaped the attention of nutrition experts until this symposium, which raised the question of whether the same health concerns should be extended to the general population. The potential hazard of a high phosphorus intake in the healthy population is illustrated by findings from acute and epidemiologic studies. Acute studies in healthy young adults demonstrate that phosphorus intakes in excess of nutrient needs may significantly disrupt the hormonal regulation of phosphorus contributing to disordered mineral metabolism, vascular calcification, bone loss, and impaired kidney function. One of the hormonal factors acutely affected by dietary phosphorus loading is fibroblast growth factor-23, which may be a key factor responsible for many of the cardiovascular disease (CVD) complications of high phosphorus intake. Increasingly, large epidemiological studies suggest that mild elevations of serum phosphorus within the normal range are associated with CVD risk in healthy populations. Few population studies link high dietary phosphorus intake to mild changes in serum phosphorus due to study design issues specific to phosphorus and inaccurate nutrient composition databases. The increasing phosphorus intake due to the use of phosphorus-containing ingredients in processed food and the growing consumption of processed convenience and fast foods is an important factor that needs to be emphasized. PMID:24038251

  4. Assessing the health impact of phosphorus in the food supply: issues and considerations.

    PubMed

    Calvo, Mona S; Moshfegh, Alanna J; Tucker, Katherine L

    2014-01-01

    The Western dietary pattern of intake common to many Americans is high in fat, refined carbohydrates, sodium, and phosphorus, all of which are associated with processed food consumption and higher risk of life-threatening chronic diseases. In this review, we focus on the available information on current phosphorus intake with this Western dietary pattern, and new knowledge of how the disruption of phosphorus homeostasis can occur when intake of phosphorus far exceeds nutrient needs and calcium intake is limited. Elevation of extracellular phosphorus, even when phosphorus intake is seemingly modest, but excessive relative to need and calcium intake, may disrupt the endocrine regulation of phosphorus balance in healthy individuals, as it is known to do in renal disease. This elevation in serum phosphate, whether episodic or chronically sustained, may trigger the secretion of regulatory hormones, whose actions can damage tissue, leading to the development of cardiovascular disease, renal impairment, and bone loss. Therefore, we assessed the health impact of excess phosphorus intake in the context of specific issues that reflect changes over time in the U.S. food supply and patterns of intake. Important issues include food processing and food preferences, the need to evaluate phosphorus intake in relation to calcium intake and phosphorus bioavailability, the accuracy of various approaches used to assess phosphorus intake, and the difficulties encountered in evaluating the relations of phosphorus intake to chronic disease markers or incident disease. PMID:24425729

  5. Effects of Phosphorus on Morphology of Hydroponically Grown Scaevola aemula R. Br. "Whirlwind Blue"

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The popular hanging basket plant, fan-flower (Scaevola aemula R. Br. ‘Whirlwind Blue’), is cultivated from low phosphorus soils and requires minimal supplemental phosphorus. To accurately evaluate the effects of phosphorus on morphology, fan-flower was grown hydroponically in order to maintain conc...

  6. Effect of microflora and lactose on the absorption of calcium, phosphorus and magnesium

    E-print Network

    Paris-Sud XI, Université de

    Effect of microflora and lactose on the absorption of calcium, phosphorus and magnesium, magnesium and phosphorus was determined in the ileum, caecum, large intestine and faeces by the mineral/Tio2 and magnesium but did have an unfavorable influence on phosphorus absorption. Lactose increased calcium

  7. Calcium acetate, an effective phosphorus binder in patients with renal failure

    Microsoft Academic Search

    Martin L Mai; Michael Emmett; Mudassir S Sheikh; Carol A Santa Ana; Lawrence Schiller; John S Fordtran

    1989-01-01

    Calcium acetate, an effective phosphorus binder in patients with renal failure. Calcium salts are increasingly used as phosphorus binders in patients with chronic renal failure. Calcium carbonate is the principal salt presently utilized, however, other calcium salts may be more effective and safer phosphorus binders. Theoretical calculations, in vitro experiments, and in vivo studies in normal subjects have shown calcium

  8. Phosphorus and arsenic profile control for high performance epitaxial base bipolar junction devices

    E-print Network

    Bashir, Rashid

    Phosphorus and arsenic profile control for high performance epitaxial base bipolar junction devices interface. The arsenic segregation is confirmed to be significantly higher than phosphorus. In addition, an increase in both the phosphorus and arsenic incorporation is observed in the presence of a highly doped

  9. RETROSPECTIVE ANALYSIS OF THE RESPONSE OF SAGINAW BAY, LAKE HURON, TO REDUCTIONS IN PHOSPHORUS LOADINGS

    EPA Science Inventory

    A retrospective analysis was conducted of the response of Saginaw Bay, Lake Huron, to a substantial reduction in external phosphorus loadings over the study period 1974-1980. Loadings to Saginaw Bay from the Saginaw River for total phosphorus and dissolved ortho phosphorus were 5...

  10. Assessing the Health Impact of Phosphorus in the Food Supply: Issues and Considerations123

    PubMed Central

    Calvo, Mona S.; Moshfegh, Alanna J.; Tucker, Katherine L.

    2014-01-01

    The Western dietary pattern of intake common to many Americans is high in fat, refined carbohydrates, sodium, and phosphorus, all of which are associated with processed food consumption and higher risk of life-threatening chronic diseases. In this review, we focus on the available information on current phosphorus intake with this Western dietary pattern, and new knowledge of how the disruption of phosphorus homeostasis can occur when intake of phosphorus far exceeds nutrient needs and calcium intake is limited. Elevation of extracellular phosphorus, even when phosphorus intake is seemingly modest, but excessive relative to need and calcium intake, may disrupt the endocrine regulation of phosphorus balance in healthy individuals, as it is known to do in renal disease. This elevation in serum phosphate, whether episodic or chronically sustained, may trigger the secretion of regulatory hormones, whose actions can damage tissue, leading to the development of cardiovascular disease, renal impairment, and bone loss. Therefore, we assessed the health impact of excess phosphorus intake in the context of specific issues that reflect changes over time in the U.S. food supply and patterns of intake. Important issues include food processing and food preferences, the need to evaluate phosphorus intake in relation to calcium intake and phosphorus bioavailability, the accuracy of various approaches used to assess phosphorus intake, and the difficulties encountered in evaluating the relations of phosphorus intake to chronic disease markers or incident disease. PMID:24425729

  11. A diatom-phosphorus transfer function for shallow, eutrophic ponds in southeast England

    Microsoft Academic Search

    Helen Bennion

    1994-01-01

    Shallow ponds in southeast England are often eutrophic with high phosphorus concentrations. The aim of this study was to develop a diatom-phosphorus ‘transfer function’ to enable past phosphorus levels in such waters to be inferred from the sediment record. A water chemistry survey of 123 randomly chosen, shallow, artificial ponds in southeast England was carried out. Principal components analysis (PCA)

  12. Increased plant growth from nitrogen addition should conserve phosphorus in terrestrial ecosystems

    E-print Network

    processes. nitrogen cycle nitrogen inputs phosphorus cycle phosphorus retention Human activities have causedIncreased plant growth from nitrogen addition should conserve phosphorus in terrestrial ecosystems, 2007) Inputs of available nitrogen (N) to ecosystems have grown over the recent past. There is limited

  13. PREDICTING CONCENTRATION OF TOTAL PHOSPHORUS AND CHLOROPHYLL 'A' IN A LAKE WITH SHORT HYDRAULIC RESIDENCE TIME

    EPA Science Inventory

    The relationship between total phosphorus and chlorophyll a concentration was determined for Skinner Lake, Indiana over an annual cycle in 1978-79. Total nitrogen: total phosphorus ratios in the epilimnion ranged from 19 to 220 suggesting a phosphorus-dependent algal yield in the...

  14. Technology for recovery of phosphorus from animal wastewater through calcium phosphate precipitation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A wastewater treatment process was developed for removal of phosphorus from livestock wastewater. The phosphorus is recovered as calcium phosphate with addition of only small quantities of liquid lime. The process is based on the distinct chemical equilibrium between phosphorus and calcium ions when...

  15. Conversion of seed phytate to utilizable phosphorus in soybean seeds expressing a bacterial phytase

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phytic acid contains the major part of the phosphorus in the soybean, chelates divalent cations, and is not digested by monogastric animals. Untreated soymeal does not provide monogastrics sufficient phosphorus and minerals, and phytic acid in the waste stream leads to phosphorus run-off. We gener...

  16. Stability of boron and phosphorus implanted tungsten silicide structures at high temperatures

    E-print Network

    Bashir, Rashid

    Stability of boron and phosphorus implanted tungsten silicide structures at high temperatures R-deposited tungsten silicide (WSi2.6) films that were implanted with boron or phosphorus and annealed at high with boron were found to be more stable than those implanted with phosphorus. With the appropriate choice

  17. Effect of liming and phosphorus application on performance of Leucaena leucocephala in acid soils

    Microsoft Academic Search

    B. Duguma; B. T. Kang; D. U. U. Okali

    1988-01-01

    Pot experiments were conducted to assess the lime and phosphorus requirements ofLeucaena leucocephala (LAM.) De Wit grown on three acid soils (Ultisols) from southeastern Nigeria. Liming and phosphorus application significantly enhanced growth ofL. leucocephala. Ammakama soil showed best effect to phosphorus application, while acidity problems were more pronounced on Onne and Isienu soils. High lime rate (2000 ppm) reduced plant

  18. NEW FORMATION OF ARYL CARBON-PHOSPHORUS BONDS Vladimir C~HKVA,Milan HAJEK

    E-print Network

    Cirkva, Vladimir

    -Arbuzov reaction is not applicable to the formation of aryl carbon-phosphorus bonds. However, on- ly few methodsNEW FORMATION OF ARYL CARBON-PHOSPHORUS BONDS Vladimir C~HKVA,Milan HAJEK Institute of Chemical@icpf.cas.cz The formation of carbon-phosphorus bonds has synthetic potential.The preparation of arylphosphonates is achived

  19. Selenium availability in berseem (Trifolium alexandrinum) as affected by selenium and phosphorus application

    Microsoft Academic Search

    Mahendra Singh; Pradeep Kumar Malhotra

    1976-01-01

    The effect of selenium and phosphorus application on Berseem (Trifolium alexandrium) was studied in the green house. Each dose of selenium from O to 16 ppm decreased the dry matter yield of Berseem significantly at all the levels of applied phosphorus. Phosphorus stimulated the dry matter yield at all levels of selenium. Yields in the second cutting were of a

  20. Development of an Arcellacea (testate lobose amoebae) based transfer function for sedimentary Phosphorus in lakes

    E-print Network

    Patterson, Timothy

    Phosphorus in lakes R. Timothy Patterson a, , Helen M. Roe b , Graeme T. Swindles c a Ottawa Eutrophication Phosphorus Ontario Canada Arcellacea (testate lobose amoebae) communities were assessed from 73 arcellacean-based training set for sedimentary phosphorus (Olsen P (OP)) loading; and (2) derive a transfer

  1. ASSESSING THE PERFORMANCE AND ENVIRONMENTAL ACCEPTABILITY OF PHOSPHORUS-SATURATED OCHRE AS A FERTILISER

    E-print Network

    Heal, Kate

    1 ASSESSING THE PERFORMANCE AND ENVIRONMENTAL ACCEPTABILITY OF PHOSPHORUS-SATURATED OCHRE in the formation of ochre for which no end use has been identified. Ochre adsorbs phosphorus (P) from solution so Phosphorus (P) is an essential nutrient for both plants and animals, but in excess it can be a serious threat

  2. Electrical and optical properties of phosphorus doped Ge1 -yCy M.W. Dashiella,

    E-print Network

    Electrical and optical properties of phosphorus doped Ge1 - yCy M.W. Dashiella, *, R.T. Troegera, K source for phosphorus doping, epitaxial Ge1 - yCy films were in situ doped on Si(100) substrates during with Ge. Free carrier absorption increased with increasing phosphorus concentrations, following

  3. USE OF TURFGRASS SOD TO TRANSPORT MANURE PHOSPHORUS OUT OF IMPAIRED WATERSHEDS

    E-print Network

    Mukhtar, Saqib

    phosphorus (P). CAFOs have been identified as a possible source of the excess P. Continued application0 USE OF TURFGRASS SOD TO TRANSPORT MANURE PHOSPHORUS OUT OF IMPAIRED WATERSHEDS I. Choi1 , C where phosphorus (P) reduction is required by total maximum daily loads (TMDLs) regulation. Export

  4. UBC Social Ecological Economic Development Studies (SEEDS) Student Report An Investigation into Phosphorus Recovery Technology

    E-print Network

    into Phosphorus Recovery Technology Andy Yao Gavin Han Robert Fu Benny Chen University of British Columbia APSC the current status of the subject matter of a project/report". #12;An Investigation into Phosphorus Recovery March 29, 2012 #12;Abstract This report investigates the available phosphorus recovery technologies

  5. Is Phosphorus Fertilizer Needed in Winter Pea and Lentil Production in Central Montana?

    E-print Network

    Lawrence, Rick L.

    , 2 Western Triangle Ag. Research Center, Conrad Introduction Application of phosphorus (P) has been for the 2004-2005 crop-year. Results Grain Yield: Phosphorus application had a limited effect on grain yieldIs Phosphorus Fertilizer Needed in Winter Pea and Lentil Production in Central Montana? Guang Wen1

  6. Tracing the Sources and Biogeochemical Cycling of Phosphorus in Aquatic Systems Using

    E-print Network

    Paytan, Adina

    Chapter 21 Tracing the Sources and Biogeochemical Cycling of Phosphorus in Aquatic Systems Using to oxygen (O), which has three stable isotopes, providing a system to track phosphorus cycling to understand phosphorous dynamics in many environments. 21.1 Introduction Phosphorus (P, atomic number 15

  7. Integrating spectral indices into prediction models of soil phosphorus in a subtropical wetland

    E-print Network

    Grunwald, Sabine

    Integrating spectral indices into prediction models of soil phosphorus in a subtropical wetland R WCA-2A Prediction models Phosphorus Wetlands Ecology Ecosystem restoration Remote sensing-2A), phosphorus enrichment has drawn a lot of attention and has led to an extensive documentation

  8. A nested catchment approach for defining the hydrological controls on non-point phosphorus transport

    E-print Network

    Scanlon, Todd

    A nested catchment approach for defining the hydrological controls on non-point phosphorus, University College, Cork, Cork, Ireland Accepted 23 December 2003 Abstract Stream water phosphorus (P. Concentration­discharge ðC­Q� relationships were developed for total phosphorus (TP) and its two components

  9. High Stability of Faceted Nanotubes and Fullerenes of Multiphase Layered Phosphorus: A Computational Study

    E-print Network

    Tománek, David

    phosphorus is considered superior to graphite for LIB applications [16,17], a similar benefit couldHigh Stability of Faceted Nanotubes and Fullerenes of Multiphase Layered Phosphorus compound of these carbon allotropes, the stable black phosphorus allotrope is a layered compound that can

  10. Semiconducting Layered Blue Phosphorus: A Computational Study Zhen Zhu and David Tomnek*

    E-print Network

    Tománek, David

    applications. We study a likely transformation pathway from black to blue phosphorus and discuss possible waysSemiconducting Layered Blue Phosphorus: A Computational Study Zhen Zhu and David Tománek* Physics; published 1 May 2014) We investigate a previously unknown phase of phosphorus that shares its layered

  11. Fertilizer Facts: August 2002, Number 29 Effects of Dust Control Coatings on Phosphorus Fertilizer Availability and

    E-print Network

    Lawrence, Rick L.

    Fertilizer Facts: August 2002, Number 29 Effects of Dust Control Coatings on Phosphorus Fertilizer) in the U.S. (Fixen, 2001). Phosphorus fertilization often does not substantially increase soil test levels highest percentage (78%) of soil samples testing either medium or lower in soil test phosphorus (P

  12. EN-019 Silviculture March 2003 Effects of Phosphorus Fertilization on the

    E-print Network

    EN-019 Silviculture March 2003 Effects of Phosphorus Fertilization on the Early Growth of Red Alder, hardwood, seedling growth, growth response, fertilization, phosphorus, silviculture CITATION: Brown, K.R and P.J. Courtin. 2003. Effects of Phosphorus Fertili- zation on the Early Growth of Red Alder

  13. Effects of phosphorus on biofilm disinfections in model drinking water distribution systems

    Microsoft Academic Search

    Wei Fang; Jiangyong Hu; Say Leong Ong

    2009-01-01

    Drinking water biofilm development is affected by the available nutrient levels and the presence of disinfectants. Phosphorus is recognized as another important limiting nutrient besides organic carbon. In this study, drinking water biofilms were developed in annular reactors to examine the effects of phosphorus on the biofilm disinfections with free chlorine and monochloramine. Phosphorus addition was found to increase the

  14. Using extension phosphorus uptake research to improve Idaho's nutrient management planning program

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Irrigated silage corn is the main crop used for phosphorus removal; however little is known about the actual amounts of phosphorus removed under southern Idaho growing conditions. The purpose of this study was to survey phosphorus removal by irrigated corn grown for silage in southern Idaho under va...

  15. Past, present, and future use of phosphorus in Chinese agriculture and its influence on phosphorus losses.

    PubMed

    Li, Haigang; Liu, Jian; Li, Guohua; Shen, Jianbo; Bergström, Lars; Zhang, Fusuo

    2015-03-01

    Large inputs of phosphorus (P) in chemical fertilizers and feed supplements since 1978 have improved soil P status in arable land in China, but have also created challenges by increasing P concentrations in manure and exacerbating water quality degradation. Arable land in China can be divided into five management zones based on soil P chemistry, with 15-92 % of arable land having lower P status than the agronomic optimum and 0.3-7.2 % having severe risks of P leaching losses. A scenario analysis of soil P budget and agronomic P demand during 2011-2030 highlighted the great pressure China faces in sustainable P management and the need for drastic changes in current practices. This includes new policies to reduce P supplementation of feed and improved P use efficiency by livestock and programs to expand the adoption of appropriate fertilization, soil conservation, and drainage management practices to minimize P losses. PMID:25681984

  16. Phosphorus containing PET and PEN by direct esterification

    Microsoft Academic Search

    C. S Wang; J. Y Shieh; Y. M Sun

    1999-01-01

    A series of various flame retardant copolyesters containing various amounts of phosphorus were synthesized by direct esterification process using the compound of [(6-oxido-6H-dibenz ?c,e??1,2? oxaphosphorin-6-yl)methyl]-butanedioic acid (ODOP-BDA) and bis (hydroxyethyl) terephthalate (BHET) or bis (hydroxyethyl) naphthalate (BHEN). The copolyesters having inherent viscosity of 0.517–0.617 dl\\/g were obtained in quantitative yield. These phosphorus-containing copolyesters have good thermal and flame retardant properties.

  17. Studies on phosphorus and calcium in poult nutrition

    E-print Network

    Khaund, Robindra Nath

    1962-01-01

    support excellent calcification in poults when they were fed 80 A. O. A. C. chick units of vitamin D per 100 Nns. of feed. Motzok and Slinger (1948) showed that 0. 62/ calcium and 0. 607, phosphorus were sufficient when the diet contained 160 units... of turkey poults to 3 weaks of age. The phosphorus supplements used in these experiments were Na2HP04, and defluorinated rock phosphate. 4 total of 210 deyeold Broad Sreasted Sronse turkey poults were wing banded and divided into groups ?f 14 biisls per...

  18. The effect of sulphur and phosphorus sources on cotton

    E-print Network

    Black, Shelton Glenn

    1958-01-01

    APPENDIX 43 Table 11. Analysis of variance for treatment effect on green weight nf plants on June Zl. , Source of Variation De rees of Freedom Mean S uare T otal Replications Treatments Phosphorus Sulphur Phosphorus X Sulphur Error 13 1 6 1... 1 1 6 77. 8 1847. 5 9765. 0 9. 0 124. 0 158. 0 Significant at the 0. 01 level of probabilrty Table 1Z. Analysis of variance for treatment effect on dry weight of pls. nts on June Zl. Source of Variation De rees of Freedom Mean S uare...

  19. Phosphorus adsorption and desorption behavior on sediments of different origins

    Microsoft Academic Search

    Qingren Wang; Yuncong Li

    2010-01-01

    Purpose  The aim of this study was to assess phosphorus-retention (Pret) capacities via P adsorption (Pads) and desorption (Pdes) by sediments collected from six different sources associated with various origins, physical, and chemical characteristics.\\u000a \\u000a \\u000a \\u000a \\u000a Materials and methods  Sediment samples were collected in the State of Florida, the USA, from estuary, marine, wetland, canal, river, and lake, respectively.\\u000a Phosphorus adsorption and desorption for

  20. Fire-resistant phosphorus containing polyimides and copolyimides

    NASA Technical Reports Server (NTRS)

    Mikroyannidis, J. A. (inventor)

    1985-01-01

    Phosphorus-containing polyimides and copolyimides are synthesized in a two-step polycondensation reaction from 1- (diorganooxyphosphonl)methly 2,4- and 2,6-diaminobenzenes and tetracarboxylic anhydride. The diorgano position of the diorganooxyphosphonyl group includes alkyl, such as ethyl, substituted alkyl, such as 2-chloroethyl, and aryl such as phenyl. The tetracarboxylic anhydries include compounds such as pyrometallitic dianhydride and benzophenone tetracarboxylic dianhydride. The glass transition temperature (Tg) of the polyimides is reduced by incorporation of the (dialkoxyphosphonyl)methyl groups. The phosphorus-containing copolyimides show a considerably higher degree of fire-resistance as compared to that of the corresponding common polyimides.

  1. Evaluation of phosphorus source coefficients as predictors of runoff phosphorus concentrations.

    PubMed

    Smith, Matt C; White, John W; Coale, Frank J

    2009-01-01

    Many states have adopted a P site index (PSI) as a risk assessment tool to determine when P-based nutrient management is required for a given agricultural field. Some PSIs use a weighting factor, the phosphorus source coefficient (PSC), to account for differences in P solubility between organic P sources. Information relating to appropriate values of PSC for various organic P sources is limited. The objectives of this study were to determine PSCs for organic P sources and to examine the relationship between PSCs and P concentrations measured in simulated rainfall runoff. An incubation study was used to calculate PSCs based on the extractability of P from organic P sources (separated and unseparated liquid dairy manure, digested dairy manure, dairy manure solids, poultry litter, and compost) relative to P from triple superphosphate fertilizer. The PSCs from the 14-d incubations were the best predictors of runoff P after 14 d soil equilibration in the runoff boxes. The values for iron-oxide strip phosphorus (FeO-P) PSC ranged from 78% for compost to 28% for poultry litter and were significantly related to runoff DR-P (r(2) = 0.80***) and FeO-P (r(2) = 0.76***) during the 14-d runoff event. Mehlich 3 PSCs ranged from 59% for compost to 30% for unseparated dairy manure and were better predictors of DR-P and FeO-P during the 56-d event (r(2) = 0.73*** and 0.65***, respectively). The results of this study indicate that PSCs based on soil incubations may improve the ability of PSCs to predict the risk of runoff transport, particularly after manure incorporation. PMID:19202029

  2. Pentacoordinate phosphorus in a high-pressure polymorph of phosphorus nitride imide P4N6(NH).

    PubMed

    Baumann, Dominik; Schnick, Wolfgang

    2014-12-22

    Coordination numbers higher than usual are often associated with superior mechanical properties. In this contribution we report on the synthesis of the high-pressure polymorph of highly condensed phosphorus nitride imide P4 N6 (NH) representing a new framework topology. This is the first example of phosphorus in trigonal-bipyramidal coordination being observed in an inorganic network structure. We were able to obtain single crystals and bulk samples of the compound employing the multi-anvil technique. ?-P4 N6 (NH) has been thoroughly characterized using X-ray diffraction, solid-state NMR and FTIR spectroscopy. The synthesis of ?-P4 N6 (NH) gives new insights into the coordination chemistry of phosphorus at high pressures. The synthesis of further high-pressure phases with higher coordination numbers exhibiting intriguing physical properties seems within reach. PMID:25124527

  3. Synthesis of 3,3-dinitroazetidine

    DOEpatents

    Hiskey, Michael A. (Los Alamos, NM)

    1995-01-01

    The compound, 3,3-dinitroazetidine, and a process of preparing 3,3-dinitroazetidine including reacting a mixture of 1-tertiary-butyl-3,3-dinitroazetidine and benzyl chloroformate to form 1-(benzyloxycarbonyl)-3,3-dinitroazetidine, reacting the 1-(benzyloxycarbonyl)-3,3-dinitroazetidine and trifluoromethanesulfonic acid to form 3,3-dinitroazetidinium trifluoromethanesulfonate, and neutralizing the 3,3-dinitroazetidinium trifluoromethanesulfonate with a base to form 3,3-dinitroazetidine are provided. Salts of the 3,3-dinitroazetidine and preparation of such salts are also disclosed.

  4. Phosphorus Chemistry and Bacterial Community Composition Interact in Brackish Sediments Receiving Agricultural Discharges

    PubMed Central

    Sinkko, Hanna; Sihvonen, Leila M.; Sivonen, Kaarina; Leivuori, Mirja; Rantanen, Matias; Paulin, Lars; Lyra, Christina

    2011-01-01

    Background External nutrient discharges have caused eutrophication in many estuaries and coastal seas such as the Baltic Sea. The sedimented nutrients can affect bacterial communities which, in turn, are widely believed to contribute to release of nutrients such as phosphorus from the sediment. Methods We investigated relationships between bacterial communities and chemical forms of phosphorus as well as elements involved in its cycling in brackish sediments using up-to-date multivariate statistical methods. Bacterial community composition was determined by terminal restriction fragment length polymorphism and cloning of the 16S rRNA gene. Results and Conclusions The bacterial community composition differed along gradients of nutrients, especially of different phosphorus forms, from the estuary receiving agricultural phosphorus loading to the open sea. This suggests that the chemical composition of sediment phosphorus, which has been affected by riverine phosphorus loading, influenced on bacterial communities. Chemical and spatial parameters explained 25% and 11% of the variation in bacterial communities. Deltaproteobacteria, presumptively sulphate and sulphur/iron reducing, were strongly associated to chemical parameters, also when spatial autocorrelation was taken into account. Sulphate reducers correlated positively with labile organic phosphorus and total nitrogen in the open sea sediments. Sulphur/iron reducers and sulphate reducers linked to iron reduction correlated positively with aluminium- and iron-bound phosphorus, and total iron in the estuary. The sulphate and sulphur/iron reducing bacteria can thus have an important role both in the mineralization and mobilization of nutrients from sediment. Significance Novelty in our study is that relationships between bacterial community composition and different phosphorus forms, instead of total phosphorus, were investigated. Total phosphorus does not necessarily bring out interactions between bacteria and phosphorus chemistry since proportions of easily usable mobile (reactive) phosphorus and immobile phosphorus forms in different sediments can vary. Our study suggested possible feedbacks between different forms of phosphorus and bacterial community composition. PMID:21747910

  5. Classical syndromes in occupational medicine: phosphorus necrosis--a classical occupational disease

    SciTech Connect

    Felton, J.S.

    1982-01-01

    A disease nearly extinct in occupational health history is phosphorus necrosis, previously seen in near-epidemic proportions among workers making phosphorus-containing matches. Similar destructive lesions were encountered early in the 20th century among personnel fabricating fireworks. Through the diligent efforts of an economist and a supportive congressman, legislation was passed in 1912 placing a tax on phosphorus matches, and because of the fiscal burden resulting, a nontoxic substitute for elemental phosphorus was adopted by all manufacturers. Today phosphorus necrosis is extremely rare, but the former presence of the disease points up both apathy and courage in the identification and eradication of a remarkably disfiguring work-caused disease.

  6. Loss of Phosphorus by Surface Runoff and Leaching from a Heavy Clay Soil under Barley and Grass Ley in Finland

    Microsoft Academic Search

    Eila Turtola; Antti Jaakkola

    1995-01-01

    Phosphorus losses by surface runoff and leaching were studied for three years in a 16-plot field on a heavy clay soil in south-west Finland to compare losses of total phosphorus (TP), particulate phosphorus (PP) and dissolved orthophosphate phosphorus (DP) from barley and grass ley plots. Barley was fertilized with 21 and 42 kg ha y P by placement technique. Ley

  7. Phosphorus nutrition of ectomycorrhizal and arbuscular mycorrhizal tree seedlings from a lowland tropical rain forest in Korup National Park, Cameroon

    Microsoft Academic Search

    BERNARD MOYERSOEN; IAN J. ALEXANDER; ALASTAIR H. FITTER

    1998-01-01

    The relationship between mycorrhizal colonisation and phosphorus acquired by seedlings of the arbuscular mycorrhizal tree Oubanguia alata Bak f. (Scytopetalaceae) and the ectomycorrhizal tree Tetraberlinia moreliana Aubr. (Caesalpinioideae) was evaluated at low and high inorganic phosphorus availabil- ity. AM colonisation was positively correlated with phosphorus uptake by O. alata at low, but not at high phosphorus availability. Seedlings growth was

  8. Managing agricultural phosphorus for water quality protection: principles for progress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The eutrophication of aquatic systems due to diffuse pollution of agricultural phosphorus (P) is a local, even regional, water quality problem that can be found world-wide. Sustainable management of P requires prudent tempering of agronomic practices, recognizing that additional steps are often requ...

  9. SEDIMENT PHOSPHORUS DYNAMICS IN TILE-FED DRAINAGE DITCHES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) losses from agriculture have been linked to eutrophication. The objectives of this work were to study the relationship between P in the water column and sediments in tile-fed drainage ditches, and determine if these ditches can be used in the management system to reduce downstream de...

  10. Chiral monodentate phosphorus ligands for rhodium-catalyzed asymmetric hydrogenation

    Microsoft Academic Search

    Thomas Jerphagnon; Jean-Luc Renaud; Christian Bruneau

    2004-01-01

    This review reports the recent developments in the field of asymmetric hydrogenation in the presence of metal catalysts containing monodentate phosphorus ligands. Besides monophosphines, that have been used at the origin of asymmetric hydrogenation, it mainly includes the use of monophosphites and monophosphoramidites, which when associated to rhodium precursors have recently led to very efficient enantioselective catalytic systems.

  11. BLOOD CHANGES IN MALLARDS EXPOSED TO WHITE PHOSPHORUS

    Microsoft Academic Search

    Donald W. Sparling; Stephanie Vann; Robert A. Grove

    1998-01-01

    White phosphorus (P 4) has been extensively used by the military for various purposes, including marking artillery impacts and as an obscurant. Target practice in an Alaskan tidal marsh during the last 4 decades has deposited large amounts of P4 particles in sediments and water, which have resulted in die-offs of several waterfowl species. Because the toxicity of P 4

  12. THE TROPHIC STATUS AND PHOSPHORUS LOADINGS OF LAKE CHAMPLAIN

    EPA Science Inventory

    Information on the trophic status of the several basins of Lake Champlain is summarized, the amounts and distribution of total phosphorus loading into the lake are evaluated, and recommendations for further study are made. The general objective is to provide basic background info...

  13. Conjugate and method for forming aminomethyl phosphorus conjugates

    DOEpatents

    Katti, Kattesh V. (Columbia, MO); Berning, Douglas E. (Columbia, MO); Volkert, Wynn A. (Columbia, MO); Ketring, Alan R. (Columbia, MO); Churchill, Robert (Columbia, MO)

    1999-01-01

    A method of forming phosphine-amine conjugates includes reacting a hydroxymethyl phosphine group of an amine-free first molecule with at least one free amine group of a second molecule to covalently bond the first molecule with the second molecule through an aminomethyl phosphorus linkage and the conjugates formed thereby.

  14. EFFECTS OF FORAGE MANAGEMENT ON PASTURE PRODUCTIVITY AND PHOSPHORUS CONTENT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of the current study were to determine the amounts of above- and below-ground plant biomass production, phosphorus (P) uptake by forage, and P concentration of cool-season grass forage as influenced by management and season. Five forage management treatments were evaluated over three...

  15. Phosphorus Retention in Streams and Wetlands: A Review

    Microsoft Academic Search

    K. R. Reddy; R. H. Kadlec; E. Flaig; P. M. Gale

    1999-01-01

    Wetlands and streams buffer the interactions among uplands and adjacent aquatic systems. Phosphorus (P) is often the key nutrient found to be limiting in both estuarine and freshwater ecosystems. As such, the ability of wetlands and streams to retain P is key to determining downstream water quality. This article reviews the processes and factors regulating P retention in streams and

  16. GRAZING MANAGEMENT EFFECTS ON SEDIMENT AND PHOSPHORUS IN SURFACE RUNOFF

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sediment and phosphorus (P) in runoff from pastures are potential non-point source pollutants in surface waters that may be influenced by surface cover, sward height, treading damage, surface slope, soil moisture, and soil P. The objectives of the current study were to evaluate their relationships w...

  17. LIVESTOCK GRAZING IMPACTS ON PHOSPHORUS IN A CARBONATE SPRING

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dissolved phosphorus loads in Appalachian River basins are directly related to the amount of land drained by carbonate aquifers. Typically, carbonate aquifers in Appalachia are characterized by a high secondary permeability associated with solutionally enlarged fractures and joints in the soluble b...

  18. Determination of Phosphorus Retention and Flux in Soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In soils and sediments, physicochemical and biological processes jointly act to control phosphorus (P) in solution. The soluble reactive P fraction is taken up by plants, sequestered in soil, or disperses in the surrounding environment. Although the primary mechanism for environmental transport of...

  19. Polyphosphate buffering by biomass with different phosphorus contents

    Microsoft Academic Search

    Willie F. Harper; Olange Anise; Eric Brown

    2006-01-01

    Polyphosphate buffering is a novel application of enhanced biological phosphorus (P) removal (EBPR) for P-deficient wastewaters with influent organic load variability. This study investigated the effect of biomass P content on polyphosphate buffering using a membrane bioreactor (MBR) and conventional bioreactor (CBR). Increasing the biomass P content increased polyphosphate buffering and the COD removal capacity, but at high P content

  20. Manure Phosphorus and Surface Water Protection III: Transport Factors

    NSDL National Science Digital Library

    This lesson addresses transport factors that may contribute to phosphorus (P) delivery to surface waters.  Erosion, runoff, subsurface flow, drainage, and distance to surface water are the main factors.  In some places, wind erosion may also be important.  The effects of management practices on P transport are discussed, and water-related P transport processes are described in detail. 

  1. Sources of phosphorus exported from an agricultural watershed in Pennsylvania

    Microsoft Academic Search

    Andrew N. Sharpley; William J. Gburek; G. Folmar; H. B. Pionke

    1999-01-01

    Freshwater eutrophication is usually controlled by inputs of phosphorus (P). As point source controls have decreased P inputs, the relative contributions of nonpoint inputs from agriculture have increased. Thus, remedial strategies are now being directed towards minimizing P export from agriculture. To identify critical sources of P, we investigated chemical and hydrologic factors controlling P export from a mixed land

  2. Phosphorus Limitation of Microbial Processes in Moist Tropical Forests

    E-print Network

    Cleveland, Cory

    of varying age underlying tropical rain forests in southwestern Costa Rica, combined with direct; fertilization; tropical rain forest; phosphorus; carbon. INTRODUCTION In many terrestrial ecosystems, primary in many lowland tropical rain forests (Martinelli and others 1999). Moreover, many of these forests lie

  3. Isolation and characterization of few-layer black phosphorus

    NASA Astrophysics Data System (ADS)

    Castellanos-Gomez, Andres; Vicarelli, Leonardo; Prada, Elsa; Island, Joshua O.; Narasimha-Acharya, K. L.; Blanter, Sofya I.; Groenendijk, Dirk J.; Buscema, Michele; Steele, Gary A.; Alvarez, J. V.; Zandbergen, Henny W.; Palacios, J. J.; van der Zant, Herre S. J.

    2014-09-01

    Isolation and characterization of mechanically exfoliated black phosphorus flakes with a thickness down to two single-layers is presented. A modification of the mechanical exfoliation method, which provides higher yield of atomically thin flakes than conventional mechanical exfoliation, has been developed. We present general guidelines to determine the number of layers using optical microscopy, Raman spectroscopy and transmission electron microscopy (TEM) in a fast and reliable way. Moreover, we demonstrate that the exfoliated flakes are highly crystalline and that they are stable even in free-standing form through Raman spectroscopy and TEM measurements. A strong thickness dependence of the band structure is found by density functional theory (DFT) calculations. The exciton binding energy, within an effective mass approximation, is also calculated for different number of layers. Our computational results for the optical gap are consistent with preliminary photoluminescence results on thin flakes. Finally, we study the environmental stability of black phosphorus flakes finding that the flakes are very hydrophilic and that long term exposure to air moisture etches black phosphorus away. Nonetheless, we demonstrate that the aging of the flakes is slow enough to allow fabrication of field-effect transistors with strong ambipolar behavior. DFT calculations also give us insight into the water-induced changes of the structural and electronic properties of black phosphorus.

  4. Phosphorus uptake into algal biofilms in a lowland chalk river

    Microsoft Academic Search

    H. P Jarvie; C Neal; A Warwick; J White; M Neal; H. D Wickham; L. K Hill; M. C Andrews

    2002-01-01

    This paper examines the growth and uptake of phosphorus into algal biofilms in the River Kennet, a lowland chalk (Cretaceous-age) stream in southern England. Algal biofilms were grown on artificial plastic substrates (templates) placed (i) on the riverbed and (ii) within the mid-water column. Experiments were set up to examine differences in growth rates of newly colonising biofilms compared with

  5. REVIEW PAPER Diversity in phosphorus mobilisation and uptake

    E-print Network

    Paris-Sud XI, Université de

    be taken up as inorganic orthophosphate (Pi), either as H2PO4 - or HPO4 2- , depending on the pH of soil concentrations in free Pi, soil may contain high levels of phosphorus that are not directly available to plant inorganic orthophosphate (Pi) concentrations, soil may contain high total P contents, as insoluble mineral P

  6. Phosphorus Cycling in Tropical Forests Growing on Highly Weathered Soils

    E-print Network

    Cleveland, Cory

    soil orders (Gelisols; Palm et al. 2007), seven are common in tropical forests: Alfisols, EntisolsChapter 14 Phosphorus Cycling in Tropical Forests Growing on Highly Weathered Soils Sasha C. Reed introduced a model describing patterns of soil phospho- rus (P) pools and availability during ecosystem

  7. Pools and distributions of soil phosphorus in China

    Microsoft Academic Search

    Chi Zhang; Hanqin Tian; Jiyuan Liu; Shaoqiang Wang; Mingliang Liu; Shufen Pan; Xuezheng Shi

    2005-01-01

    We have investigated the pools and distributions of soil phosphorus (P) in the top 50 cm of soil in China by using a combination of total and available P information from more than 2400 soil profiles and a map of soil types at a resolution of 1:1,000,000. Our estimates indicate that the average total P density and available P density

  8. Total Phosphorus Mass Balance Models for the Lower Boise River

    USGS Multimedia Gallery

    USGS hydrologic technician Alvin Sablan calibrates an acoustic Doppler current profiler before collecting a discharge measurement on the Boise River near Caldwell, Idaho. The discharge measurement and other data were used to develop total phosphorus mass balance models for the lower Boise River. The...

  9. PHOSPHORUS AVAILABILITY TO SUGARCANE IN HISTOSOLS UNDER PERIODIC FLOODING

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Subsidence of organic soils and phosphorus (P) release into surface water are two major issues facing agriculture in the Everglades Agricultural Area in south Florida. Raising the water table depth and periodic flooding may reduce the rate of oxidation of these soils. This study was conducted to qua...

  10. A TOOL FOR ASSESSING BMP EFFECTIVENESS FOR PHOSPHORUS POLLUTION CONTROL

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A Best Management Practice (BMP) assessment tool was developed as a part of an effort to address the phosphorus (P) pollution and associated eutrophication problem affecting the Cannonsville Reservoir, part of the New York City water supply system. P reaching the reservoir is thought to emanate fro...

  11. Dairy heifer diets, manure management, and runoff phosphorus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Manure application to cropland can contribute to runoff losses of phosphorus and eutrophication of surface waters. We conducted a series of three rainfall simulation experiments to assess the effects of dairy heifer diet P, manure incorporation, application rate, and soil test P on runoff P losses f...

  12. CHANGES IN MANURE EXTRACTABLE PHOSPHORUS WITH METAL ADDITION AND COMPOSTING

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High phosphorus content of manure reduces allowable application rate to fields. Manure treatments may reduce the soluble or extractable P and allow for higher application rates. Laboratory bench composter studies were conducted using poultry litter and poultry manure to determine changes in manure...

  13. Biochar effects on phosphorus pools in three soils from Minnesota

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This greenhouse study was set up to assess the changes in the soil phosphorus (P) pools of three soils used for agricultural production in Minnesota as a result of biochar application and crop nutrient uptake. The soils included: excessively well-drained Hubbard loamy sand; poorly drained, calcareou...

  14. Direct Speciation of Phosphorus in Alum-Amended Poultry Litter

    E-print Network

    Sparks, Donald L.

    surface complexes on aluminum hydroxide that had been formed by the hydrolysis of alum. However, a complex (PL) with aluminum sulfate (alum) has proven to be effective in reducing water-soluble phosphorus (P (aluminum sulfate hydrate) (7, 8). Alum has received particular interest in

  15. Phosphorus Sorption Characteristics of the Bronx River Bed Sediments

    Microsoft Academic Search

    J. Wang; H. K. Pant

    2007-01-01

    Phosphorus (P) is a major nutrient for plant growth, and it is often the primary limiting nutrient controlling algal blooms in aquatic and semi-aquatic systems. The Bronx River of New York City, NY, USA constitutes freshwater and coastal water systems, and the water quality of the systems is considered lower than the standard levels. Algal blooms and subsequent oxygen (O2)

  16. Phosphorus Losses from Agricultural Watersheds in the Mississippi Delta

    EPA Science Inventory

    High phosphorus (P) loss from agricultural fields has been an environmental concern because of potential water quality problems in streams and lakes. To better understand the process of P loss, rainfall, surface runoff, sediment, ortho-P and total P (TP) were measured (1996 to 2...

  17. AGRICULTURAL PHOSPHORUS AND THE ENVIRONMENT: CHALLENGING SCIENCE, PRACTICE AND POLICY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While phosphorus (P) is essential input for profitable crop and livestock agriculture, its loss in runoff accelerates eutrophication of receiving surface waters. Best Management Practices (BMPs) to mitigate P transfers to surface water must address specific agronomic, environmental and socio-econom...

  18. Reducing Erosion and Phosphorus Movement in Potato Systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil erosion and phosphorus (P) runoff can be severe in potato production systems in the Northeast U.S., which are characterized by intensive tillage, minimal ground cover, low crop residue return, and steep slopes. We used rainfall simulators in the greenhouse and field to assess sediment and P mov...

  19. Phosphorus recovery from wastewater by struvite crystallization: property of aggregates.

    PubMed

    Ye, Zhilong; Shen, Yin; Ye, Xin; Zhang, Zhaoji; Chen, Shaohua; Shi, Jianwen

    2014-05-01

    Struvite crystallization is a promising method to remove and recover phosphorus from wastewater to ease both the scarcity of phosphorus rock resources and water eutrophication worldwide. To date, although various kinds of reactor systems have been developed, supporting methods are required to control the struvite fines flushing out of the reactors. As an intrinsic property, aggregation is normally disregarded in the struvite crystallization process, although it is the key factor in final particle size and therefore guarantees phosphorus recovery efficiency. The present study developed a method to analyze the characteristics of struvite aggregates using fractal geometry, and the influence of operational parameters on struvite aggregation was evaluated. Due to its typical orthorhombic molecular structure, struvite particles are prone to crystallize into needle or rod shapes, and aggregate at the corners or edges of crystals. The determined fractal dimension (Dpf) of struvite aggregates was 1.52-1.31, with the corresponding range of equivalent diameter (d0.5) at 295.9-85.4 ?m. Aggregates formed in relatively low phosphorus concentrations (3.0-5.0 mmol/L) and mildly alkaline conditions (pH 9.0-9.5) displayed relatively compact structures, large aggregate sizes and high aggregation strength. Increasing pH values led to continuous decrease of aggregate sizes, while the variation of Dpf was insignificant. As to the aggregate evolution, fast growth in a short time followed by a long steady stage was observed. PMID:25079629

  20. Energy conservation and pollution abatement at phosphorus furnaces

    Microsoft Academic Search

    Barber

    1983-01-01

    A process and product of waste recovery at phosphorus furnaces is disclosed wherein small sized discrete particles of carbonaceous material or beneficiated phosphate ore are mixed with a mineral acid, an alkaline fluid and water, and the reacted mixture is tumbled in a horizontal cylinder at a temperature below that at which the carbonaceous material oxidizes to form agglomerates which

  1. COMMENT ON 'A MODEL FOR TOTAL PHOSPHORUS IN SAGINAW BAY'

    EPA Science Inventory

    The subject paper (Canale and Squire 1976) presents the results of the application of a steady-state mass balance model to chloride and total phosphorus data for Saginaw Bay in 1974. In this work, the steady-state model was shown to be inadequate for this system, except during st...

  2. Struvite precipitation and phosphorus removal using magnesium sacrificial anode.

    PubMed

    Kruk, Damian J; Elektorowicz, Maria; Oleszkiewicz, Jan A

    2014-04-01

    Struvite precipitation using magnesium sacrificial anode as the only source of magnesium is presented. High-purity magnesium alloy cast anode was found to be very effective in recovery of high-quality struvite from water solutions and from supernatant of fermented waste activated sludge from a wastewater treatment plant that does not practice enhanced biological phosphorus removal. Struvite purity was strongly dependent on the pH and the electric current density. Optimum pH of the 24 mM phosphorus and 46 mM ammonia solution (1:1.9 P:N ratio) was in the broad range between 7.5 and 9.3, with struvite purity exceeding 90%. Increasing the current density resulted in elevated struvite purity. No upper limits were observed in the studied current range of 0.05-0.2 A. Phosphorus removal rate was proportional to the current density and comparable for tests with water solutions and with the supernatant from fermented sludge. The highest P-removal rate achieved was 4.0 mg PO4-P cm(-2) h(-1) at electric current density of 45 A m(-2). Initial substrate concentrations affected the rate of phosphorus removal. The precipitated struvite accumulated in bulk liquid with significant portions attached to the anode surface from which regular detachment occurred. PMID:24387911

  3. Effects of urbanization on phosphorus flows in a residential system

    Microsoft Academic Search

    D. H. Waller

    A model represents, on an annual basis, water and nutrient flows into and through a residential system. Changing model parameters to represent alternative development patterns helps to illustrate the dramatic effects of urbanization on nutrient flows. Analysis of sources and magnitudes of phosphorous discharges from a 1-ha residential area suggests that vegetation is the principal source of phosphorus, and that

  4. Disorders of Calcium, Phosphorus, and Magnesium Metabolism in the Neonate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Approximately 98% of the calcium, 80% of the phosphorus, and 65% of the magnesium in the body are in the skeleton. These elements, often referred to as the "bone minerals" are also constituents of the intracellular and extracellular spaces. The metabolism of these bone minerals and mineralization of...

  5. Phosphorus Budget and Management Strategies for an Urban Wisconsin Lake

    Microsoft Academic Search

    William F. James; John W. Barko; Harry L. Eakin; Patrick W. Sorge

    2002-01-01

    Multiple external and internal phosphorus (P) sources to an urban lake, Half Moon Lake in Wisconsin, were examined during the summer of 1999 in order to develop management strategies for effective P control and reversal of eutrophication (Trophic State Index=74). Internal recycling of P accounted for 80% of the summer P budget of the lake. Flux of P from the

  6. COMPARISONS OF MODELS PREDICTING AMBIENT LAKE PHOSPHORUS CONCENTRATIONS

    EPA Science Inventory

    The Vollenweider, Dillon, and Larsen/Mercier models for predicting ambient lake phosphorus concentrations and classifying lakes by trophic state are compared in this report. The Dillon and Larsen/Mercier models gave comparable results in ranking 39 lakes relative to known ambient...

  7. Process for recovery of phosphorus from solid manure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Land application of manure in regions with intense confined livestock and poultry production is an environmental concern when land is limiting because it promotes soil phosphorus (P) surplus and potential pollution of water resources. Although manure can be moved off the farm, its transportation bec...

  8. Water quality remediation faces unprecedented challenges from ‘legacy phosphorus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural best management practices (BMPs) have been very successful at reducing phosphorus (P) losses at the edge-of-field, but there has often been disappointingly little improvement in downstream water quality and ecological services1. New evidence indicates that a major reason is the contin...

  9. 46 CFR 151.50-50 - Elemental phosphorus in water.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...vessel following cooling of the water above the cargo to a temperature...Coils in which steam or hot water is circulated to heat the cargo...bolted cover plates and gaskets resistant to the attack of phosphorus...During cargo transfer, a water hose shall be connected to...

  10. Absorption and storage of phosphorus by larval Manduca sexta

    Microsoft Academic Search

    H. Arthur Woods; Marc C. Perkins; James J. Elser; Jon F. Harrison

    2002-01-01

    The role of phosphorus (P) in numerous important biological structures, coupled with the observation that P-content of many insect foods is disproportionately low, suggests that P may be a critical nutrient for growing insects — however, the few studies examining the effects of dietary P on insect performance have generally found only weak relationships. This mismatch may be reconciled by

  11. MANURE SOURCE EFFECTS ON SOIL PHOSPHORUS FRACTIONS AND THEIR DISTRIBUTIONS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Manure can be applied to soils as a major source of nutrients such as phosphorus (P). The environmental chemistry and plant availability of applied P are influenced by the chemical forms of P in the solid phase. The objectives of this study were to determine the amounts, availability, and chemical f...

  12. Electric field induced gap modification in ultrathin blue phosphorus

    NASA Astrophysics Data System (ADS)

    Ghosh, Barun; Nahas, Suhas; Bhowmick, Somnath; Agarwal, Amit

    2015-03-01

    We investigate the possibility of band structure engineering in the recently predicted 2D layered form of blue phosphorus via an electric field (Ez) applied perpendicular to the layer(s). Using density functional theory, we study the effect of a transverse electric field in monolayer as well as three differently stacked bilayer structures of blue phosphorus. We find that for Ez>0.2 V/Å the direct energy gap at the ? point, which is much larger than the default indirect band gap of mono- and bilayer blue phosphorus, decreases linearly with the increasing electric field, becomes comparable to the default indirect band gap at Ez?0.45 (0.35 ) V/Å for monolayer (bilayers), and decreases further until the semiconductor to metal transition of 2D blue phosphorus takes place at Ez?0.7 (0.5 ) V/Å for monolayer (bilayers). Calculated values of the electron and hole effective masses along various high symmetry directions in the reciprocal lattice suggests that the mobility of charge carriers is also influenced by the applied electric field.

  13. Soil controls of phosphorus runoff: management barriers and opportunities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The persistent problem of eutrophication, the biological enrichment of surface waters akin to aging, has produced a vast literature on soil phosphorus (P) effects on runoff water quality. This paper considers the mechanisms controlling soil P transfers from agricultural soils to runoff waters, highl...

  14. Carbon, nitrogen, and phosphorus transport by world rivers

    Microsoft Academic Search

    M. Meybeck

    1982-01-01

    The various forms (dissolved and particulate, organic and inorganic) of carbon, nitrogen, and phosphorus in world rivers are reviewed from literature data. Natural levels are based mainly on major rivers for the subarctic and tropical zones which are still unpolluted and on smaller streams for the temperate zone. Atmospheric fallout is also reviewed. Natural contents of dissolved organic carbon (DOC)

  15. Module for phosphorus separation and recycling from liquid manures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A method has been developed to extract and concentrate soluble phosphates from livestock wastewater. The research was conducted over a 10-year period and went from initial bench studies and discovery, to pilot module development, to full-scale demonstrations of the phosphorus (P) module in swine fa...

  16. Sediment Phosphorus Release at Beaver Reservoir, Northwest Arkansas, USA, 20022003

    E-print Network

    Chaubey, Indrajeet

    Sediment Phosphorus Release at Beaver Reservoir, Northwest Arkansas, USA, 2002­2003: A Preliminary- ditions from intact sediment cores collected at Beaver Reservoir, northwest Arkansas, (2) evaluate, and (3) compare external and internal P loads to Beaver Reservoir. Six intact sediment cores were

  17. MANAGING PHOSPHORUS IN AGRICULTURE AND PROTECTING THE ENVIRONMENT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Inputs of phosphorus (P) are essential for profitable crop and livestock agriculture. However, its export in watershed runoff can accelerate the eutrophication of receiving fresh waters. The rapid growth and intensification of crop and livestock farming in many areas has created regional imbalances...

  18. Phosphorus budget-basin relationships for Lake Okeechobee tributary basins

    Microsoft Academic Search

    C. F. Boggess; E. G. Flaig; R. C. Fluck

    1995-01-01

    Accelerated cultural eutrophication of Lake Okeechobee, FL by excessive phosphorus (P) loading has generated a need to determine P sources and sinks in the watershed. Average annual P budgets were estimated for each of the 19 tributary basins in the northern Lake Okeechobee watershed for the period 1985–1989. Net P imports were estimated based on P usage by land use

  19. Fertilizer Effectiveness of Phosphorus Recovered from Broiler Litter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) can be recovered from broiler litter using a new process (‘quick wash’). However, limited information is available on the beneficial reuse of this P product as plant fertilizer. The objective of this study was to determine the agronomic effectiveness of this P material. A 7-wk greenho...

  20. Ceratophyllum demersum – phosphorus interactions in nutrient enriched aquaria

    Microsoft Academic Search

    Paola Lombardo; G. Dennis Cooke

    2003-01-01

    High macrophyte density in shallow lakes is often associated with clear water, especially when the non-rooted, submerged angiosperm Ceratophyllum demersum is dominant. Lack of true roots and high surface area:volume ratio suggest that nutrient uptake from the water column by C. demersum may be high. Therefore, possible competition for nutrients, including phosphorus (P), could contribute to phytoplankton inhibition.

  1. FGD gypsum filters remove soluble phosphorus from agricultural drainage waters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Decades of chicken litter applications has led to phosphorus (P) levels up to ten times the agronomic optimum in soils of the Delmarva Peninsula. This legacy P is a major source of P entering drainage ditches that eventually empty into the Chesapeake Bay. A Flue Gas Desulfurization (FGD) gypsum ditc...

  2. REDUCING MANURE PHOSPHORUS SOLUBILITY WITH ALUM AND COAL COMBUSTION BYPRODUCTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Animal manures contain large amounts of soluble phosphorus (P). This P is prone to runoff losses when manure is surface applied, contributing to water quality decline and eutrophication of streams and rivers. Here we report the efficacy of alum and three coal combustion byproducts in reducing P so...

  3. CALCIUM AND PHOSPHORUS METABOLISM IN SHEEP G.D. BRAITHWAITE

    E-print Network

    Paris-Sud XI, Université de

    CALCIUM AND PHOSPHORUS METABOLISM IN SHEEP G.D. BRAITHWAITE National Institute for Research of vitamin D, has been used successfully in dairy cows to prevent post-parturient hypocalcaemia and reduce and duration of its effect on the various processes of Ca and P metabolism has now been studied in the sheep

  4. PRODUCTION AND FEEDING STRATEGIES FOR PHOSPHORUS MANAGEMENT ON DAIRY FARMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The long-term accumulation of soil phosphorus (P) is becoming an important concern on some watersheds heavily populated with dairy farms. Management changes in crop production and feeding may be useful in reducing this accumulation of excess P, but farm profitability must be maintained or improved t...

  5. The environmentally-sound management of agricultural phosphorus

    Microsoft Academic Search

    Andrew N. Sharpley; Paul J. A. Withers

    1994-01-01

    Freshwater eutrophication is often accelerated by increased phosphorus (P) inputs, a greater share of which now come from agricultural nonpoint sources than two decades ago. Maintenance of soil P at levels sufficient for crop needs is an essential part of sustainable agriculture. However, in areas of intensive crop and livestock production in Europe and the U.S.A., P has accumulated in

  6. Phosphorus Containing Flame Retardants and Their Textile Applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this paper, we discuss the new challenge phosphorus containing flame retardant compounds and the properties for covalently bonded cotton’s surface. We showed the design, synthesis, and characterization of (2-methyl-oxiranylmethyl)-phosphonic acid dimethyl ester and [2-(dimethoxy-phosphorylmethyl)...

  7. Phosphorus fate, management and modeling in artificially drained systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) losses in agricultural drainage waters, both surface and subsurface, are much more common than once recognized and are among the most difficult form of non-point source pollution to mitigate. Major advances have been made in understanding the mechanisms of P transport and in testing a...

  8. Aquacultural Engineering 23 (2000) 315332 Reactive nitrogen and phosphorus removal

    E-print Network

    Rubloff, Gary W.

    Aquacultural Engineering 23 (2000) 315­332 Reactive nitrogen and phosphorus removal from aquaculture wastewater effluents using polymer hydrogels Dimitri R. Kioussis a , Fredrick W. Wheaton b , Peter - ), and orthophosphate (PO4 3- ) nutrient anions from the aquaculture wastewater. The hydrogels were prepared

  9. Development of phosphorus fertilizer recommendations for tomato on an oxisol

    Microsoft Academic Search

    J. R. Magalhaes; F. C. Rodrigues; P. E. F. Rossi; G. E. Wilcox; F. L. I. M. Silva

    1986-01-01

    A procedure to determine phosphorus fertilizer recommendations for tomato growing on oxisol soils was studied with 23 experimental trials in Brazil involving three phases of study. In the first phase a wide range of P contents in the soil were established and the second experimental phase was carried out on each established level of P in the soil. A square

  10. Optimizing Phosphorus and Potassium Fertilizer Recommendations using Spatial Uncertainty Assessments

    Microsoft Academic Search

    Eric Hedoin; Timothy Ray Ellsworth; Robert Hornbaker

    2007-01-01

    Variable?rate nutrient management relies on soil fertility maps, yet the associated uncertainty is typically ignored in developing recommendations. In this article, ordinary kriging (OK) and several alternatives that rely on local estimates of uncertainty derived via probability kriging (PK) are evaluated for developing phosphorus (P) and potassium (K) fertilizer recommendations, using soil data collected at two different intensities. A decision

  11. Endocrine regulation of calcium and phosphorus concentration in camel's milk.

    E-print Network

    Paris-Sud XI, Université de

    Endocrine regulation of calcium and phosphorus concentration in camel's milk. F Riad M Ben Goumi JCIAVHassan Il, Rabat, Maroc; 31NRA, Theix, France Some qualitative aspects of the milk of the dromedary suggest that the ability to produce milk of high nutritive value for offspring or for human beings during long periods

  12. Contributions of systematic tile drainage to watershed scale phosphorus transport

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) transport from agricultural fields continues be a focal point for addressing harmful algal blooms (HABs) and nuisance algae in freshwater systems throughout the world. In humid, poorly drained regions, attention has turned to P delivery through subsurface tile drainage. Research on th...

  13. Agronomic effectiveness of phosphorus materials recovered from manure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Land application of large amounts of manure from confined livestock facilities is an environmental concern often associated to excess phosphorus (P) in soils and potential pollution of water resources. Recovery of P from livestock manure is an attractive approach when on-farm application of manure i...

  14. Interactions between phosphorus deficiency and CO2 fertilization on cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) deficiency in acidic soils is a major limiting factor for crop production worldwide. A growth chamber experiment was conducted to study the limiting effect of P deficiency on cotton growth and photosynthesis (Pnet) on current and projected atmospheric carbon dioxide (CO2) concentratio...

  15. Phosphorus and calcium retention in serially harvested cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Data from 3 serial harvest trials were utilized to calculate phosphorus and calcium retention in cattle. Trial 1 evaluated three rates of gain during a growing period followed by a common finishing diet utilizing British crossbred steers. Four steers were harvested from each treatment following th...

  16. PRECIPITATION AND INACTIVATION OF PHOSPHORUS AS A LAKE RESTORATION TECHNIQUE

    EPA Science Inventory

    Many eutrophic lakes respond slowly following nutrient diversion because of long water retention times, and the recycling of phosphorus from sediments and other internal sources. Treatment of lakes with aluminum sulfate and/or sodium aluminate is a successful method for removing ...

  17. Phosphorus distribution in a soil fertilized with recovered manure phosphates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phosphorus (P) can be recovered in a concentrated form from livestock manure and poultry litter. A greenhouse study was conducted to evaluate the short-term leaching potential and plant availability of P from recovered P materials from liquid pig manure (SRP) and broiler litter (LRP) in a characteri...

  18. Method for recovery of phosphorus from animal wastewater

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A wastewater treatment process and systems were developed to extract and concentrate phosphates from livestock wastewater. The research was conducted over a 10-year period and went from initial bench studies to pilot module development to full-scale demonstrations of the phosphorus module on swine f...

  19. Conjugate and method for forming aminomethyl phosphorus conjugates

    SciTech Connect

    Katti, K.V.; Berning, D.E.; Volkert, W.A.; Ketring, A.R.; Churchill, R.

    1999-09-07

    A method of forming phosphine-amine conjugates includes reacting a hydroxymethyl phosphine group of an amine-free first molecule with at least one free amine group of a second molecule to covalently bond the first molecule with the second molecule through an aminomethyl phosphorus linkage and the conjugates formed thereby.

  20. Original article The release of phosphorus from heavily fertilized soils

    E-print Network

    Paris-Sud XI, Université de

    Original article The release of phosphorus from heavily fertilized soils to dilute electrolytes, accepted 12 March 1999) Abstract - Soils heavily fertilized with P can contribute to the enrichment of P different, heavily fertilized European soils. We studied: a) long-term P release under 'sta- tic' conditions