Detection of Forgeries of Dutch and Flemish Paintings of the XVII-XVIII Centuries by means of Spectroscopic Techniques

NASA Astrophysics Data System (ADS)

Shabunya-Klyachkovskaya, E. V.; Kiris, V. V.; Shimko, A. N.; Belkov, M. V.; Raikov, S. N.

2014-01-01

Results of spectroscopic examinations of three paintings that by the formal and stylistic features can be attributed to the Dutch and Flemish schools of the XVII-XVIIIth centuries were presented. It was supposed that one of the paintings was created by David Teniers the Younger. The signature ″L. de Moni″ was found on the paint layer of another painting. Inorganic art pigments including those of the XIXth century were identified using laser-induced breakdown spectroscopy. Fourier-transform IR spectroscopy was used to determine the paint binders, which allowed the lower limits of the creation time of these artworks to be defined. Results of a microscopic examination of the stratigraphic structure revealed that the creation technology of these artworks differed from that of Dutch and Flemish artists of the XVII-XVIIIth centuries. Thus, all three investigated paintings were XXth century stylistic forgeries of Dutch and Flemish paintings of the XVI-XVIIIth centuries.

Phytoplankton in the ocean use non-phosphorus lipids in response to phosphorus scarcity.

PubMed

Van Mooy, Benjamin A S; Fredricks, Helen F; Pedler, Byron E; Dyhrman, Sonya T; Karl, David M; Koblízek, Michal; Lomas, Michael W; Mincer, Tracy J; Moore, Lisa R; Moutin, Thierry; Rappé, Michael S; Webb, Eric A

2009-03-05

Phosphorus is an obligate requirement for the growth of all organisms; major biochemical reservoirs of phosphorus in marine plankton include nucleic acids and phospholipids. However, eukaryotic phytoplankton and cyanobacteria (that is, 'phytoplankton' collectively) have the ability to decrease their cellular phosphorus content when phosphorus in their environment is scarce. The biochemical mechanisms that allow phytoplankton to limit their phosphorus demand and still maintain growth are largely unknown. Here we show that phytoplankton, in regions of oligotrophic ocean where phosphate is scarce, reduce their cellular phosphorus requirements by substituting non-phosphorus membrane lipids for phospholipids. In the Sargasso Sea, where phosphate concentrations were less than 10 nmol l-1, we found that only 1.3 +/- 0.6% of phosphate uptake was used for phospholipid synthesis; in contrast, in the South Pacific subtropical gyre, where phosphate was greater than 100 nmol l-1, plankton used 17 6% (ref. 6). Examination of the planktonic membrane lipids at these two locations showed that classes of sulphur- and nitrogen-containing membrane lipids, which are devoid of phosphorus, were more abundant in the Sargasso Sea than in the South Pacific. Furthermore, these non-phosphorus, 'substitute lipids' were dominant in phosphorus-limited cultures of all of the phytoplankton species we examined. In contrast, the marine heterotrophic bacteria we examined contained no substitute lipids and only phospholipids. Thus heterotrophic bacteria, which compete with phytoplankton for nutrients in oligotrophic regions like the Sargasso Sea, appear to have a biochemical phosphorus requirement that phytoplankton avoid by using substitute lipids. Our results suggest that phospholipid substitutions are fundamental biochemical mechanisms that allow phytoplankton to maintain growth in the face of phosphorus limitation.

CXBN-2 CubeSat – ELaNa XVII

NASA Image and Video Library

2016-12-08

The Cosmic X-Ray Background NanoSat-2 (CXBN-2) CubeSat Mission developed by Morehead State University and its partners the Keldysh Institute (Moscow, Russia), the Maysville Community and Technical College (Morehead, KY) and KYSpace LLC (Lexington, KY) will increase the precision of measurements of the Cosmic X-Ray Background in the 30-50 keV range to a precision of <5%, thereby constraining models that attempt to explain the relative contribution of proposed sources lending insight into the underlying physics of the early universe. The mission addresses a fundamental science question that is central to our understanding of the structure, origin, and evolution of the universe by potentially lending insight into both the high-energy background radiation and into the evolution of primordial galaxies. Launched by NASA’s CubeSat Launch Initiative NET April 18, 2017 ELaNa XVII mission on the seventh Orbital-ATK Cygnus Commercial Resupply Services (OA-7) to the International Space Station and deployed on tbd.

Indicators: Phosphorus

EPA Pesticide Factsheets

Phosphorus, like nitrogen, is a critical nutrient required for all life. Phosphate (PO4), which plays major roles in the formation of DNA, cellular energy, and cell membranes (and plant cell walls). Too much phosphorus can create water quality problems.

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

Rethinking early Earth phosphorus geochemistry.

PubMed

Pasek, Matthew A

2008-01-22

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 (HPO(3)(2-)), 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.

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.

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...

Complete genome sequence of a genotype XVII Newcastle disease virus, isolated from an apparently healthy domestic duck in Nigeria

USDA-ARS?s Scientific Manuscript database

The first complete genome sequence of a strain of Newcastle disease virus (NDV) of genotype XVII is described here. A velogenic strain (duck/Nigeria/903/KUDU-113/1992) was isolated from an apparently healthy free-roaming domestic duck sampled in Kuru, Nigeria, in 1992. Phylogenetic analysis of the f...

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

USGS Publications Warehouse

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

2011-01-01

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 <5 to >70 µmol · g-1. Deposition is highly focused, with ~70% 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.

Measurement of the Radiative Decay of the Longest-Lived Level in the Fe XVII Spectrum

NASA Astrophysics Data System (ADS)

Brown, Gregory V.; Beiersdorfer, Peter; Träbert, Elmar

2014-08-01

The Fe XVII emission spectrum comprises several very prominent X-ray lines that play an important role in the study of many astrophysical objects. Among the Fe XVII X-ray lines, those emanating from a 3s level, i.e., lines 3F, 3G, and M2, invariably appear too strong compared to the lines emanating from a 3d level, i.e., lines 3C and 3D, when compared to theory. Two of the four 3s levels are metastable, which means they have a rather long radiative decay time compared to collisional processes. The decay rate of the 2p^53s J=2 level has recently been measured at the Livermore EBIT facility [J. R. Crespo López-Urrutia and P. Beiersdorfer, ApJ 721, 576 (2010)], and the scatter of predictions by a factor of 1.7 has been reduced to a measurement uncertainty of merely a few percent. Even longer-lived is the J=0 level of the same 2p^53s configuration. Theory predicts an exclusive magnetic dipole decay to the lowest J=1 level of the same 2p^53s configuration, i.e. to the upper level of line 3G. There appear to be fewer predictions for this rate than for the rates associated with the other Fe XVII levels. Various calculations yield a decay rate near 16 000 s-1 for this level (or a level lifetime near 63 µs). If this value is correct, electron-impact collisions affect line ratios tied to this level at densities between about 10^10 cm-3 and 10^13 cm-3, that is, exactly at many coronal densities of present interest. We have used the Livermore EBIT facility to measure the M1 decay rate of the 2p^53s J=0 level. We find a value commensurate with the value predicted by the Flexible Atomic Code.Work performed under auspices of U.S. D.o.E. by DE-AC52-07NA27344 and supported by NASA's APRA progam under Interagency Agreement NNG13WF991.

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...

Use of annual phosphorus loss estimator (APLE) model to evaluate a phosphorus index

USDA-ARS?s Scientific Manuscript database

Maryland’s Phosphorus Site Index (MD-PSI) has been used to guide management decisions to minimize the potential for phosphorus (P) loss from agricultural fields in Maryland since 2002. The index was recently revised and renamed the University of Maryland Phosphorus Management Tool (UM-PMT), and the...

Dietary Phosphorus Intake and the Kidney

PubMed Central

Chang, Alex R.; Anderson, Cheryl

2017-01-01

Although phosphorus is an essential nutrient required for multiple physiological functions, recent research raises concerns that high phosphorus intake could have detrimental effects on health. Phosphorus is abundant in the food supply of developed countries, occurring naturally in protein-rich foods and as an additive in processed foods. High phosphorus intake can cause vascular and renal calcification, renal tubular injury, and premature death in multiple animal models. Small studies in human suggest that high phosphorus intake may result in positive phosphorus balance and correlate with renal calcification and albuminuria. Although serum phosphorus is strongly associated with cardiovascular disease, progression of kidney disease, and death, limited data exist linking high phosphorus intake directly to adverse clinical outcomes. Further prospective studies are needed to determine whether phosphorus intake is a modifiable risk factor for kidney disease. PMID:28613982

Phosphorus speciation by coupled HPLC-ICPMS: low level determination of reduced phosphorus in natural materials

NASA Astrophysics Data System (ADS)

Atlas, Zachary; Pasek, Matthew; Sampson, Jacqueline

2015-04-01

Phosphorus is a geologically important minor element in the Earth's crust commonly found as relatively insoluble apatite. This constraint causes phosphorus to be a key limiting nutrient in biologic processes. Despite this, phosphorus plays a direct role in the formation of DNA, RNA and other cellular materials. Recent works suggest that since reduced phosphorus is considerably more soluble than oxidized phosphorus that it was integrally involved in the development of life on the early Earth and may continue to play a role in biologic productivity to this day. This work examines a new method for quantification and identification of reduced phosphorus as well as applications to the speciation of organo-phosphates separated by coupled HPLC - ICP-MS. We show that reduced phosphorus species (P1+, P3+ and P5+) are cleanly separated in the HPLC and coupled with the ICPMS reaction cell, using oxygen as a reaction gas to effectively convert elemental P to P-O. Analysis at M/Z= 47 producing lower background and flatter baseline chromatography than analyses performed at M/Z = 31. Results suggest very low detection limits (0.05 μM) for P species analyzed as P-O. Additionally we show that this technique has potential to speciate at least 5 other forms of phosphorus compounds. We verified the efficacy of method on numerous materials including leached Archean rocks, suburban retention pond waters, blood and urine samples and most samples show small but detectible levels of reduced phosphorus and or organo-phaospates. This finding in nearly all substances analyzed supports the assumption that the redox processing of phosphorus has played a significant role throughout the history of the Earth and it's presence in the present environment is nearly ubiquitous with the reduced oxidation state phosphorus compounds, phosphite and hypophosphite, potentially acting as significant constituents in the anaerobic environment.

Virtual phosphorus ore requirement of Japanese economy.

PubMed

Matsubae, Kazuyo; Kajiyama, Jun; Hiraki, Takehito; Nagasaka, Tetsuya

2011-08-01

Phosphorus is indispensable for agricultural production. Hence, the consumption of imported food indirectly implies the import of phosphorus resources. The global consumption of agricultural products depends on a small number of ore-producing countries. For sustainable management of phosphorus resources, the global supply and demand network should be clarified. In this study, we propose the virtual phosphorus ore requirement as a new indicator of the direct and indirect phosphorus requirements for our society. The virtual phosphorus ore requirement indicates the direct and indirect demands for phosphorus ore transformed into agricultural products and fertilizer. In this study, the virtual phosphorus ore requirement was evaluated for the Japanese economy in 2005. Importantly, the results show that our society requires twice as much phosphorus ore as the domestic demand for fertilizer production. The phosphorus contained in "eaten" agricultural products was only 12% of virtual phosphorus ore requirement. Copyright © 2011 Elsevier Ltd. All rights reserved.

Phosphorus poisoning in waterfowl

USGS Publications Warehouse

Coburn, D.R.; DeWitt, J.B.; Derby, J.V.; 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.

Phosphorus oxide gate dielectric for black phosphorus field effect transistors

NASA Astrophysics Data System (ADS)

Dickerson, W.; Tayari, V.; Fakih, I.; Korinek, A.; Caporali, M.; Serrano-Ruiz, M.; Peruzzini, M.; Heun, S.; Botton, G. A.; Szkopek, T.

2018-04-01

The environmental stability of the layered semiconductor black phosphorus (bP) remains a challenge. Passivation of the bP surface with phosphorus oxide, POx, grown by a reactive ion etch with oxygen plasma is known to improve photoluminescence efficiency of exfoliated bP flakes. We apply phosphorus oxide passivation in the fabrication of bP field effect transistors using a gate stack consisting of a POx layer grown by reactive ion etching followed by atomic layer deposition of Al2O3. We observe room temperature top-gate mobilities of 115 cm2 V-1 s-1 in ambient conditions, which we attribute to the low defect density of the bP/POx interface.

Evolution of the global phosphorus cycle.

PubMed

Reinhard, Christopher T; Planavsky, Noah J; Gill, Benjamin C; Ozaki, Kazumi; Robbins, Leslie J; Lyons, Timothy W; Fischer, Woodward W; Wang, Chunjiang; Cole, Devon B; Konhauser, Kurt O

2017-01-19

The macronutrient phosphorus is thought to limit primary productivity in the oceans on geological timescales. Although there has been a sustained effort to reconstruct the dynamics of the phosphorus cycle over the past 3.5 billion years, it remains uncertain whether phosphorus limitation persisted throughout Earth's history and therefore whether the phosphorus cycle has consistently modulated biospheric productivity and ocean-atmosphere oxygen levels over time. Here we present a compilation of phosphorus abundances in marine sedimentary rocks spanning the past 3.5 billion years. We find evidence for relatively low authigenic phosphorus burial in shallow marine environments until about 800 to 700 million years ago. Our interpretation of the database leads us to propose that limited marginal phosphorus burial before that time was linked to phosphorus biolimitation, resulting in elemental stoichiometries in primary producers that diverged strongly from the Redfield ratio (the atomic ratio of carbon, nitrogen and phosphorus found in phytoplankton). We place our phosphorus record in a quantitative biogeochemical model framework and find that a combination of enhanced phosphorus scavenging in anoxic, iron-rich oceans and a nutrient-based bistability in atmospheric oxygen levels could have resulted in a stable low-oxygen world. The combination of these factors may explain the protracted oxygenation of Earth's surface over the last 3.5 billion years of Earth history. However, our analysis also suggests that a fundamental shift in the phosphorus cycle may have occurred during the late Proterozoic eon (between 800 and 635 million years ago), coincident with a previously inferred shift in marine redox states, severe perturbations to Earth's climate system, and the emergence of animals.

Phosphorus cycling. Major role of planktonic phosphate reduction in the marine phosphorus redox cycle.

PubMed

Van Mooy, B A S; Krupke, A; Dyhrman, S T; Fredricks, H F; Frischkorn, K R; Ossolinski, J E; Repeta, D J; Rouco, M; Seewald, J D; Sylva, S P

2015-05-15

Phosphorus in the +5 oxidation state (i.e., phosphate) is the most abundant form of phosphorus in the global ocean. An enigmatic pool of dissolved phosphonate molecules, with phosphorus in the +3 oxidation state, is also ubiquitous; however, cycling of phosphorus between oxidation states has remained poorly constrained. Using simple incubation and chromatography approaches, we measured the rate of the chemical reduction of phosphate to P(III) compounds in the western tropical North Atlantic Ocean. Colonial nitrogen-fixing cyanobacteria in surface waters played a critical role in phosphate reduction, but other classes of plankton, including potentially deep-water archaea, were also involved. These data are consistent with marine geochemical evidence and microbial genomic information, which together suggest the existence of a vast oceanic phosphorus redox cycle. Copyright © 2015, American Association for the Advancement of Science.

Peak phosphorus - peak food? The need to close the phosphorus cycle.

PubMed

Rhodes, Christopher J

2013-01-01

The peak in the world production of phosphorus has been predicted to occur in 2033, based on world reserves of rock phosphate (URR) reckoned at around 24,000 million tonnes (Mt), with around 18,000 Mt remaining. This figure was reckoned-up to 71,000 Mt, by the USGS, in 2012, but a production maximum during the present century is still highly probable. There are complex issues over what the demand will be for phosphorus in the future, as measured against a rising population (from 7 billion to over 9 billion in 2050), and a greater per capita demand for fertiliser to grow more grain, in part to feed animals and meet a rising demand for meat by a human species that is not merely more populous but more affluent. As a counterweight to this, we may expect that greater efficiencies in the use of phosphorus - including recycling from farms and of human and animal waste - will reduce the per capita demand for phosphate rock. The unseen game changer is peak oil, since phosphate is mined and recovered using machinery powered by liquid fuels refined from crude oil. Hence, peak oil and peak phosphorus might appear as conjoined twins. There is no unequivocal case that we can afford to ignore the likelihood of a supply-demand gap for phosphorus occurring sometime this century, and it would be perilous to do so.

Response of Sugarcane in a Red Ultisol to Phosphorus Rates, Phosphorus Sources, and Filter Cake

PubMed Central

Prado, Renato de Mello; Campos, Cid Naudi Silva; Rosatto Moda, Leandro; de Lima Vasconcelos, Ricardo; Pizauro Júnior, João Martins

2015-01-01

We evaluated the effect of phosphorus application rates from various sources and in the presence or absence of filter cake on soil phosphorus, plant phosphorus, changes in acid phosphatase activity, and sugarcane productivity grown in Eutrophic Red Ultisol. Three P sources were used (triple superphosphate, Araxa rock phosphate, and Bayovar rock phosphate) and four application rates (0, 90, 180, and 360 kg ha−1 of P2O5) in the presence or absence of filter cake (7.5 t ha−1, dry basis). The soil P, the accumulated plant P, the leaf acid phosphatase activity and straw, the stalk productivity, the concentration of soluble solids in the juice (Brix), the juice sucrose content (Pol), and the purity were the parameters evaluated. We found that P applications increased levels of soil, leaf, and juice phosphorus and led to higher phosphorus accumulation and greater stalk and straw productivity. These levels were highest in the presence of filter cake. Acid phosphatase activity decreased with increasing plant phosphorus concentration. Phosphate fertilization did not show effect on sugarcane technological quality. We concluded that P application, regardless of source, improved phosphorus nutrition and increased productivity in sugarcane and, when associated with filter cake, reduced the need for mineral fertilizer. PMID:26078993

SIPCAn (Separation, Isolation, Purification, Characterization, and Analysis): A One-Term, Integrated Project for the Undergraduate Organic Laboratory

ERIC Educational Resources Information Center

Dintzner, Matthew R.; Kinzie, Charles R.; Pulkrabek, Kimberly A.; Arena, Anthony F.

2011-01-01

SIPCAn, an acronym for separation, isolation, purification, characterization, and analysis, is presented as a one-term, integrated project for the first-term undergraduate organic laboratory course. Students are assigned two mixtures of unknown organic compounds--a mixture of two liquid compounds and a mixture of two solid compounds--at the…

Energy and phosphorus recovery from black water.

PubMed

de Graaff, M S; Temmink, H; Zeeman, G; Buisman, C J N

2011-01-01

Source-separated black water (BW) (toilet water) containing 38% of the organic material and 68% of the phosphorus in the total household waste (water) stream including kitchen waste, is a potential source for energy and phosphorus recovery. The energy recovered, in the form of electricity and heat, is more than sufficient for anaerobic treatment, nitrogen removal and phosphorus recovery. The phosphorus balance of an upflow anaerobic sludge blanket reactor treating concentrated BW showed a phosphorus conservation of 61% in the anaerobic effluent. Precipitation of phosphate as struvite from this stream resulted in a recovery of 0.22 kgP/p/y, representing 10% of the artificial phosphorus fertiliser production in the world. The remaining part of the phosphorus ended up in the anaerobic sludge, mainly due to precipitation (39%). Low dilution and a high pH favour the accumulation of phosphorus in the anaerobic sludge and this sludge could be used as a phosphorus-enriched organic fertiliser, provided that it is safe regarding heavy metals, pathogens and micro-pollutants.

Phosphorus and Nutrition in Chronic Kidney Disease

PubMed Central

González-Parra, Emilio; Gracia-Iguacel, Carolina; Egido, Jesús; Ortiz, Alberto

2012-01-01

Patients with renal impairment progressively lose the ability to excrete phosphorus. Decreased glomerular filtration of phosphorus is initially compensated by decreased tubular reabsorption, regulated by PTH and FGF23, maintaining normal serum phosphorus concentrations. There is a close relationship between protein and phosphorus intake. In chronic renal disease, a low dietary protein content slows the progression of kidney disease, especially in patients with proteinuria and decreases the supply of phosphorus, which has been directly related with progression of kidney disease and with patient survival. However, not all animal proteins and vegetables have the same proportion of phosphorus in their composition. Adequate labeling of food requires showing the phosphorus-to-protein ratio. The diet in patients with advanced-stage CKD has been controversial, because a diet with too low protein content can favor malnutrition and increase morbidity and mortality. Phosphorus binders lower serum phosphorus and also FGF23 levels, without decreasing diet protein content. But the interaction between intestinal dysbacteriosis in dialysis patients, phosphate binder efficacy, and patient tolerance to the binder could reduce their efficiency. PMID:22701173

Development of a Phosphorus-Eutrophication Management Strategy for Vermont: Evaluations Available Phosphorus Loads.

DTIC Science & Technology

1985-11-01

1980). " J . V. DePinto, T . C. Young, J . S. Bonner, and P. W. Rodgers, "Microbial Recycling of Phytoplankton Phosphorus," Canadian Journal of...algal growth, 97 9 3 S. C. Chapra, H. D. Wicke, T . M. Heidtke, "Effectiveness of Treatment to Meet Phosphorus Objectives in the Great Lakes," J . Water...Conference on Management Strategies for Phosphorus in the Environment (Selper Ltd., London, 1985.) 1 0 4 G. F. Lee, et al. (1980). 105 T . C. Young and J . V

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Renyu; Trzynadlowski, Bart; Dunham, Scott T.

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 getteringmore » 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.« less

PHOSPHORUS RECOVERY FROM SEWAGE

EPA Science Inventory

Phosphorus is a growth limiting nutrient that is mined from rock ore, refined, used in fertilizers, and discharged to the environment through municipal sewage. The impacts of phosphorus discharge include severe eutrophication of fresh water bodies. The future sustainable use of...

Estimation of phosphorus flux in rivers during flooding.

PubMed

Chen, Yen-Chang; Liu, Jih-Hung; Kuo, Jan-Tai; Lin, Cheng-Fang

2013-07-01

Reservoirs in Taiwan are inundated with nutrients that result in algal growth, and thus also reservoir eutrophication. Controlling the phosphorus load has always been the most crucial issue for maintaining reservoir water quality. Numerous agricultural activities, especially the production of tea in riparian areas, are conducted in watersheds in Taiwan. Nutrients from such activities, including phosphorus, are typically flushed into rivers during flooding, when over 90% of the yearly total amount of phosphorous enters reservoirs. Excessive or enhanced soil erosion from rainstorms can dramatically increase the river sediment load and the amount of particulate phosphorus flushed into rivers. When flow rates are high, particulate phosphorus is the dominant form of phosphorus, but sediment and discharge measurements are difficult during flooding, which makes estimating phosphorus flux in rivers difficult. This study determines total amounts of phosphorus transport by measuring flood discharge and phosphorous levels during flooding. Changes in particulate phosphorus, dissolved phosphorus, and their adsorption behavior during a 24-h period are analyzed owing to the fact that the time for particulate phosphorus adsorption and desorption approaching equilibrium is about 16 h. Erosion of the reservoir watershed was caused by adsorption and desorption of suspended solids in the river, a process which can be summarily described using the Lagmuir isotherm. A method for estimating the phosphorus flux in the Daiyujay Creek during Typhoon Bilis in 2006 is presented in this study. Both sediment and phosphorus are affected by the drastic discharge during flooding. Water quality data were collected during two flood events, flood in June 9, 2006 and Typhoon Bilis, to show the concentrations of suspended solids and total phosphorus during floods are much higher than normal stages. Therefore, the drastic changes of total phosphorus, particulate phosphorus, and dissolved phosphorus in

Potential Impact of Dietary Choices on Phosphorus Recycling and Global Phosphorus Footprints: The Case of the Average Australian City

PubMed Central

Metson, Geneviève S.; Cordell, Dana; Ridoutt, Brad

2016-01-01

Changes in human diets, population increases, farming practices, and globalized food chains have led to dramatic increases in the demand for phosphorus fertilizers. Long-term food security and water quality are, however, threatened by such increased phosphorus consumption, because the world’s main source, phosphate rock, is an increasingly scarce resource. At the same time, losses of phosphorus from farms and cities have caused widespread water pollution. As one of the major factors contributing to increased phosphorus demand, dietary choices can play a key role in changing our resource consumption pathway. Importantly, the effects of dietary choices on phosphorus management are twofold: First, dietary choices affect a person or region’s “phosphorus footprint” – the magnitude of mined phosphate required to meet food demand. Second, dietary choices affect the magnitude of phosphorus content in human excreta and hence the recycling- and pollution-potential of phosphorus in sanitation systems. When considering options and impacts of interventions at the city scale (e.g., potential for recycling), dietary changes may be undervalued as a solution toward phosphorus sustainability. For example, in an average Australian city, a vegetable-based diet could marginally increase phosphorus in human excreta (an 8% increase). However, such a shift could simultaneously dramatically decrease the mined phosphate required to meet the city resident’s annual food demand by 72%. Taking a multi-scalar perspective is therefore key to fully exploring dietary choices as one of the tools for sustainable phosphorus management. PMID:27617261

Studies on the phosphorus requirement and proper calcium/phosphorus ratio in the diet of the black sea bream ( Sparus macrocephalus)

NASA Astrophysics Data System (ADS)

Liu, Jingke; Li, Maotang; Wang, Keling; Wang, Xincheng; Liu, Jianking

1993-06-01

An expriment on the phosphorus requirement and the proper Ca/P ratio in the diet of the black sea bream using the phosphorus gradient method (with casein as basic diet, sodium dihydrogen phosphate as source of phosphorus, and calcium lactate as source of calcium) showed that growth was greatly affected by the diet's phosphorus content and Ca/P ratio. Inadequate phosphorus in the diet resulted in slow growth and poor food conversion ratio (FCR). Analyses of the fish body showed it contained a high level of lipid but a low level of moisture, ash, calcium and phosphorus. The optimal values of phosphorus and Ca/P ratio in the black sea bream diet are 0.68% and 1∶2 respectively. Phosphorus in excess of this optimum value resulted in slow growth or even death. The results of this experiment clearly indicated that phosphorus is the principal mineral additive affecting black sea bream growth.

Speciation of Phosphorus by coupled HPLC-ICPMS: Application for quantification of reduced forms of phosphorus in rocks and natural waters.

NASA Astrophysics Data System (ADS)

Atlas, Z. D.; Pasek, M. A.; Sampson, J.

2014-12-01

Phosphorus is a geologically important element making up approximately 0.12 % of the Earth's crust. It is commonly found as relatively insoluble apatite and this causes phosphorus to be a limiting nutrient in biologic processes. Despite this, phosphorus is a key element in DNA, RNA and other cellular materials. Recent works suggest that reduced phosphorus played a substantial role in the development of life on the early Earth. Reduced phosphorus is considerably more soluble than oxidized phosphorus, and reduced phosphorus may continue to play a role in biologic productivity. This study examines a new methodology for quantification of reduced phosphorus separated by coupled HPLC - ICP-MS. We show that phosphorus species (P1+, P3+ and P5+) are cleanly separated in the HPLC and coupled with the ICP-MS reaction cell (using O2 gas) effectively convert elemental P to P-O producing lower background and flatter baseline chromatography. Results suggest very low detection limits (0.05 mM) for P species analyzed as P-O at M/Z = 47. Additionally this technique has potential to speciate at least 5 other metastable forms of phosphorus. We verified this method on numerous materials including leached Archean rocks to suburban retention pond waters and many samples show small but detectible levels of reduced phosphorus. These data highlight a significant role of redox processing of phosphorus throughout the history of the Earth, with the reduced oxidation state phosphorus compounds, phosphite and hypophosphite, potentially acting as significant constituents in the anaerobic environment.

Redistribution of phosphorus during Ni0.9Pt0.1-based silicide formation on phosphorus implanted Si substrates

NASA Astrophysics Data System (ADS)

Lemang, M.; Rodriguez, Ph.; Nemouchi, F.; Juhel, M.; Grégoire, M.; Mangelinck, D.

2018-02-01

Phosphorus diffusion and its distribution during the solid-state reactions between Ni0.9Pt0.1 and implanted Si substrates are studied. Silicidation is achieved through a first rapid thermal annealing followed by a selective etching and a direct surface annealing. The redistribution of phosphorus in silicide layers is investigated after the first annealing for different temperatures and after the second annealing. Phosphorus concentration profiles obtained thanks to time of flight secondary ion mass spectrometry and atom probe tomography characterizations for partial and total reactions of the deposited 7 nm thick Ni0.9Pt0.1 film are presented. Phosphorus segregation is observed at the Ni0.9Pt0.1 surface and at Ni2Si interfaces during Ni2Si formation and at the NiSi surface and the NiSi/Si interface after NiSi formation. The phosphorus is evidenced in low concentrations in the Ni2Si and NiSi layers. Once NiSi is formed, a bump in the phosphorus concentration is highlighted in the NiSi layer before the NiSi/Si interface. Based on these profiles, a model for the phosphorus redistribution is proposed to match this bump to the former Ni2Si/Si interface. It also aims to bind the phosphorus segregation and its low concentration in different silicides to a low solubility of phosphorus in Ni2Si and in NiSi and a fast diffusion of phosphorus at their grain boundaries. This model is also substantiated by a simulation using a finite difference method in one dimension.

PREFACE: XVII International Scientific Conference ''RESHETNEV READINGS''

NASA Astrophysics Data System (ADS)

2015-01-01

The International Scientific Conference ''RESHETNEV READINGS'' is dedicated to the memory of Mikhail Reshetnev, an outstanding scientist, chief-constructor of space-rocket systems and communication satellites. The current volume represents selected proceedings of the main conference materials which were published by XVII International Scientific Conference ''RESHETNEV READINGS'' held on November 12 - 14, 2013. Plenary sessions, round tables and forums will be attended by famous scientists, developers and designers representing the space technology sector, as well as professionals and experts in the IT industry. A number of outstanding academic figures expressed their interest in an event of such a level including Jaures Alferov, Vice-president of the Russian Academy of Sciences (RAS), Academician of RAS, Nobel laureate, Dirk Bochar, General Secretary of the European Federation of National Engineering Associates (FEANI), Prof. Yuri Gulyaev, Academician of RAS, Member of the Presidium of RAS, President of the International Union of Scientific and Engineering Associations, Director of the Institute of Radio Engineering and Electronics of RAS, as well as rectors of the largest universities in Russia, chief executives of well-known research enterprises and representatives of big businesses. We would like to thank our main sponsors such as JSC ''Reshetnev Information Satellite Systems'', JSC ''Krasnoyarsk Engineering Plant'', Central Design Bureau ''Geophysics'', Krasnoyarsk Region Authorities. These enterprises and companies are leading ones in the aerospace branch. It is a great pleasure to cooperate and train specialists for them.

Phosphorus K4 Crystal: A New Stable Allotrope

PubMed Central

Liu, Jie; Zhang, Shunhong; Guo, Yaguang; Wang, Qian

2016-01-01

The intriguing properties of phosphorene motivate scientists to further explore the structures and properties of phosphorus materials. Here, we report a new allotrope named K4 phosphorus composed of three-coordinated phosphorus atoms in non-layered structure which is not only dynamically and mechanically stable, but also possesses thermal stability comparable to that of the orthorhombic black phosphorus (A17). Due to its unique configuration, K4 phosphorus exhibits exceptional properties: it possesses a band gap of 1.54 eV which is much larger than that of black phosphorus (0.30 eV), and it is stiffer than black phosphorus. The band gap of the newly predicted phase can be effectively tuned by appling hydrostastic pressure. In addition, K4 phosphorus exibits a good light absorption in visible and near ultraviolet region. These findings add additional features to the phosphorus family with new potential applications in nanoelectronics and nanomechanics. PMID:27857232

Comprehensive Utilization of Iron and Phosphorus from High-Phosphorus Refractory Iron Ore

NASA Astrophysics Data System (ADS)

Sun, Yongsheng; Zhang, Qi; Han, Yuexin; Gao, Peng; Li, Guofeng

2018-02-01

An innovative process of coal-based reduction followed by magnetic separation and dephosphorization was developed to simultaneously recover iron and phosphorus from one typical high-phosphorus refractory iron ore. The experimental results showed that the iron minerals in iron ore were reduced to metallic iron during the coal-based reduction and the phosphorus was enriched in the metallic iron phase. The CaO-SiO2-FeO-Al2O3 slag system was used in the dephosphorization of metallic iron. A hot metal of 99.17% Fe and 0.10% P was produced with Fe recovery of 84.41%. Meanwhile, a dephosphorization slag of 5.72% P was obtained with P recovery of 67.23%. The contents of impurities in hot metal were very low, and it could be used as feedstock for steelmaking after a secondary refining. Phosphorus in the dephosphorization slag mainly existed in the form of a 5CaO·P2O5·SiO2 solid solution where the P2O5 content is 13.10%. At a slag particle size of 20.7 μm (90% passing), 94.54% of the P2O5 could be solubilized in citric acid, indicating the slag met the feedstock requirements in phosphate fertilizer production. Consequently, the proposed process achieved simultaneous Fe and P recovery, paving the way to comprehensive utilization of high-phosphorus refractory iron ore.

Phosphorus recovery from wastes

USDA-ARS?s Scientific Manuscript database

Phosphorus (P) is an important macro-nutrient essential for all living organisms and phosphate rock is the main raw material for all inorganic P fertilizers. It is expected that there will be a P peak and resulting P fertilizer shortage in near future. In general, phosphorus use efficiency is low a...

Do soils loose phosphorus with dissolved organic matter?

NASA Astrophysics Data System (ADS)

Kaiser, K.; Brödlin, D.; Hagedorn, F.

2014-12-01

During ecosystem development and soil formation, primary mineral sources of phosphorus are becoming increasingly depleted. Inorganic phosphorus forms tend to be bound strongly to or within secondary minerals, thus, are hardly available to plants and are not leached from soil. What about organic forms of phosphorus? Since rarely studied, little is known on the composition, mobility, and bioavailability of dissolved organic phosphorus. There is some evidence that plant-derived compounds, such as phytate, bind strongly to minerals as well, while microbial compounds, such as nucleotides and nucleic acids, may represent more mobile fractions of soil phosphorus. In some weakly developed, shallow soils, leaching losses of phosphorus seem to be governed by mobile organic forms. Consequently, much of the phosphorus losses observed during initial stages of ecosystem development may be due to the leaching of dissolved organic matter. However, the potentially mobile microbial compounds are enzymatically hydrolysable. Forest ecosystems on developed soils already depleted in easily available inorganic phosphorus are characterized by rapid recycling of organic phosphors. That can reduce the production of soluble forms of organic phosphorus as well as increase the enzymatic hydrolysis and subsequent plant uptake of phosphorus bound within dissolved organic matter. This work aims at giving an outlook to the potential role of dissolved organic matter in the cycling of phosphorus within developing forest ecosystems, based on literature evidence and first results of ongoing research.

Visualizing Alternative Phosphorus Scenarios for Future Food Security

PubMed Central

Neset, Tina-Simone; Cordell, Dana; Mohr, Steve; VanRiper, Froggi; White, Stuart

2016-01-01

The impact of global phosphorus scarcity on food security has increasingly been the focus of scientific studies over the past decade. However, systematic analyses of alternative futures for phosphorus supply and demand throughout the food system are still rare and provide limited inclusion of key stakeholders. Addressing global phosphorus scarcity requires an integrated approach exploring potential demand reduction as well as recycling opportunities. This implies recovering phosphorus from multiple sources, such as food waste, manure, and excreta, as well as exploring novel opportunities to reduce the long-term demand for phosphorus in food production such as changing diets. Presently, there is a lack of stakeholder and scientific consensus around priority measures. To therefore enable exploration of multiple pathways and facilitate a stakeholder dialog on the technical, behavioral, and institutional changes required to meet long-term future phosphorus demand, this paper introduces an interactive web-based tool, designed for visualizing global phosphorus scenarios in real time. The interactive global phosphorus scenario tool builds on several demand and supply side measures that can be selected and manipulated interactively by the user. It provides a platform to facilitate stakeholder dialog to plan for a soft landing and identify a suite of concrete priority options, such as investing in agricultural phosphorus use efficiency, or renewable fertilizers derived from phosphorus recovered from wastewater and food waste, to determine how phosphorus demand to meet future food security could be attained on a global scale in 2040 and 2070. This paper presents four example scenarios, including (1) the potential of full recovery of human excreta, (2) the challenge of a potential increase in non-food phosphorus demand, (3) the potential of decreased animal product consumption, and (4) the potential decrease in phosphorus demand from increased efficiency and yield gains in

Visualizing Alternative Phosphorus Scenarios for Future Food Security.

PubMed

Neset, Tina-Simone; Cordell, Dana; Mohr, Steve; VanRiper, Froggi; White, Stuart

2016-01-01

The impact of global phosphorus scarcity on food security has increasingly been the focus of scientific studies over the past decade. However, systematic analyses of alternative futures for phosphorus supply and demand throughout the food system are still rare and provide limited inclusion of key stakeholders. Addressing global phosphorus scarcity requires an integrated approach exploring potential demand reduction as well as recycling opportunities. This implies recovering phosphorus from multiple sources, such as food waste, manure, and excreta, as well as exploring novel opportunities to reduce the long-term demand for phosphorus in food production such as changing diets. Presently, there is a lack of stakeholder and scientific consensus around priority measures. To therefore enable exploration of multiple pathways and facilitate a stakeholder dialog on the technical, behavioral, and institutional changes required to meet long-term future phosphorus demand, this paper introduces an interactive web-based tool, designed for visualizing global phosphorus scenarios in real time. The interactive global phosphorus scenario tool builds on several demand and supply side measures that can be selected and manipulated interactively by the user. It provides a platform to facilitate stakeholder dialog to plan for a soft landing and identify a suite of concrete priority options, such as investing in agricultural phosphorus use efficiency, or renewable fertilizers derived from phosphorus recovered from wastewater and food waste, to determine how phosphorus demand to meet future food security could be attained on a global scale in 2040 and 2070. This paper presents four example scenarios, including (1) the potential of full recovery of human excreta, (2) the challenge of a potential increase in non-food phosphorus demand, (3) the potential of decreased animal product consumption, and (4) the potential decrease in phosphorus demand from increased efficiency and yield gains in

Proposed biokinetic model for phosphorus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leggett, Richard Wayne

2014-06-04

This paper reviews data related to the biokinetics of phosphorus in the human body and proposes a biokinetic model for systemic phosphorus for use in updated International Commission on Radiological Protection (ICRP) guidance on occupational intake of radionuclides. Compared with the ICRP s current occupational model for phosphorus (Publication 68, 1994) the proposed model provides a more realistic description of the paths of movement of phosphorus in the body and improved consistency with experimental, medical, and environmental data on the time-dependent distribution and retention of phosphorus following uptake to blood. For acute uptake of 32P to blood, the proposed modelmore » yields roughly a 50% decrease in dose estimates for bone surface and red marrow and a 6-fold increase in estimates for liver and kidney compared with the biokinetic model of Publication 68 (applying Publication 68 dosimetric models in both sets of calculations). For acute uptake of 33P to blood, the proposed model yields roughly a 50% increase in dose estimates for bone surface and red marrow and a 7-fold increase in estimates for liver and kidney compared with the model of Publication 68.« less

21 CFR 862.1580 - Phosphorus (inorganic) test system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Phosphorus (inorganic) test system. 862.1580... Systems § 862.1580 Phosphorus (inorganic) test system. (a) Identification. A phosphorus (inorganic) test system is a device intended to measure inorganic phosphorus in serum, plasma, and urine. Measurements of...

21 CFR 862.1580 - Phosphorus (inorganic) test system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Phosphorus (inorganic) test system. 862.1580... Systems § 862.1580 Phosphorus (inorganic) test system. (a) Identification. A phosphorus (inorganic) test system is a device intended to measure inorganic phosphorus in serum, plasma, and urine. Measurements of...

Yellow phosphorus-induced Brugada phenocopy.

PubMed

Dharanipradab, Mayakrishnan; Viswanathan, Stalin; Kumar, Gokula Raman; Krishnamurthy, Vijayalatchumy; Stanley, Daphene Divya

Metallic phosphides (of aluminum and phosphide) and yellow phosphorus are commonly used rodenticide compounds in developing countries. Toxicity of yellow phosphorus mostly pertains to the liver, kidney, heart, pancreas and the brain. Cardiotoxicity with associated Brugada ECG pattern has been reported only in poisoning with metallic phosphides. Brugada phenocopy and hepatic dysfunction were observed in a 29-year-old male following yellow phosphorus consumption. He had both type 1 (day1) and type 2 (day2) Brugada patterns in the electrocardiogram, which resolved spontaneously by the third day without hemodynamic compromise. Toxins such as aluminum and zinc phosphide have been reported to induce Brugada ECG patterns due to the generation of phosphine. We report the first case of yellow phosphorus-related Brugada phenocopy, without hemodynamic compromise or malignant arrhythmia. Copyright © 2017 Elsevier Inc. All rights reserved.

The phosphorus cost of agricultural intensification in the tropics.

PubMed

Roy, Eric D; Richards, Peter D; Martinelli, Luiz A; Coletta, Luciana Della; Lins, Silvia Rafaela Machado; Vazquez, Felipe Ferraz; Willig, Edwin; Spera, Stephanie A; VanWey, Leah K; Porder, Stephen

2016-04-18

Agricultural intensification in the tropics is one way to meet rising global food demand in coming decades(1,2). Although this strategy can potentially spare land from conversion to agriculture(3), it relies on large material inputs. Here we quantify one such material cost, the phosphorus fertilizer required to intensify global crop production atop phosphorus-fixing soils and achieve yields similar to productive temperate agriculture. Phosphorus-fixing soils occur mainly in the tropics, and render added phosphorus less available to crops(4,5). We estimate that intensification of the 8-12% of global croplands overlying phosphorus-fixing soils in 2005 would require 1-4 Tg P yr(-1) to overcome phosphorus fixation, equivalent to 8-25% of global inorganic phosphorus fertilizer consumption that year. This imposed phosphorus 'tax' is in addition to phosphorus added to soils and subsequently harvested in crops, and doubles (2-7 Tg P yr(-1)) for scenarios of cropland extent in 2050(6). Our estimates are informed by local-, state- and national-scale investigations in Brazil, where, more than any other tropical country, low-yielding agriculture has been replaced by intensive production. In the 11 major Brazilian agricultural states, the surplus of added inorganic fertilizer phosphorus retained by soils post harvest is strongly correlated with the fraction of cropland overlying phosphorus-fixing soils (r(2) = 0.84, p < 0.001). Our interviews with 49 farmers in the Brazilian state of Mato Grosso, which produces 8% of the world's soybeans mostly on phosphorus-fixing soils, suggest this phosphorus surplus is required even after three decades of high phosphorus inputs. Our findings in Brazil highlight the need for better understanding of long-term soil phosphorus fixation elsewhere in the tropics. Strategies beyond liming, which is currently widespread in Brazil, are needed to reduce phosphorus retention by phosphorus-fixing soils to better manage the Earth

Novel Alleles of Phosphorus-Starvation Tolerance 1 Gene (PSTOL1) from Oryza rufipogon Confers High Phosphorus Uptake Efficiency

PubMed Central

Neelam, Kumari; Thakur, Shiwali; Neha; Yadav, Inderjit S.; Kumar, Kishor; Dhaliwal, Salwinder S.; Singh, Kuldeep

2017-01-01

Limited phosphorus availability in the soil is one of the major constraints to the growth and productivity of rice across Asian, African and South American countries, where 50% of the rice is grown under rain-fed systems on poor and problematic soils. With an aim to determine novel alleles for enhanced phosphorus uptake efficiency in wild species germplasm of rice Oryza rufipogon, we investigated phosphorus uptake1 (Pup1) locus with 11 previously reported SSR markers and sequence characterized the phosphorus-starvation tolerance 1 (PSTOL1) gene. In the present study, we screened 182 accessions of O. rufipogon along with Vandana as a positive control with SSR markers. From the analysis, it was inferred that all of the O. rufipogon accessions undertaken in this study had an insertion of 90 kb region, including Pup1-K46, a diagnostic marker for PSTOL1, however, it was absent among O. sativa cv. PR114, PR121, and PR122. The complete PSTOL1 gene was also sequenced in 67 representative accessions of O. rufipogon and Vandana as a positive control. From comparative sequence analysis, 53 mutations (52 SNPs and 1 nonsense mutation) were found in the PSTOL1 coding region, of which 28 were missense mutations and 10 corresponded to changes in the amino acid polarity. These 53 mutations correspond to 17 haplotypes, of these 6 were shared and 11 were scored only once. A major shared haplotype was observed among 44 accessions of O. rufipogon along with Vandana and Kasalath. Out of 17 haplotypes, accessions representing 8 haplotypes were grown under the phosphorus-deficient conditions in hydroponics for 60 days. Significant differences were observed in the root length and weight among all the genotypes when grown under phosphorus deficiency conditions as compared to the phosphorus sufficient conditions. The O. rufipogon accession IRGC 106506 from Laos performed significantly better, with 2.5 times higher root weight and phosphorus content as compared to the positive control Vandana

Novel Alleles of Phosphorus-Starvation Tolerance 1 Gene (PSTOL1) from Oryza rufipogon Confers High Phosphorus Uptake Efficiency.

PubMed

Neelam, Kumari; Thakur, Shiwali; Neha; Yadav, Inderjit S; Kumar, Kishor; Dhaliwal, Salwinder S; Singh, Kuldeep

2017-01-01

Limited phosphorus availability in the soil is one of the major constraints to the growth and productivity of rice across Asian, African and South American countries, where 50% of the rice is grown under rain-fed systems on poor and problematic soils. With an aim to determine novel alleles for enhanced phosphorus uptake efficiency in wild species germplasm of rice Oryza rufipogon , we investigated phosphorus uptake1 ( Pup1 ) locus with 11 previously reported SSR markers and sequence characterized the phosphorus-starvation tolerance 1 ( PSTOL1 ) gene. In the present study, we screened 182 accessions of O. rufipogon along with Vandana as a positive control with SSR markers. From the analysis, it was inferred that all of the O. rufipogon accessions undertaken in this study had an insertion of 90 kb region, including Pup1 -K46, a diagnostic marker for PSTOL1 , however, it was absent among O. sativa cv. PR114, PR121, and PR122. The complete PSTOL1 gene was also sequenced in 67 representative accessions of O. rufipogon and Vandana as a positive control. From comparative sequence analysis, 53 mutations (52 SNPs and 1 nonsense mutation) were found in the PSTOL1 coding region, of which 28 were missense mutations and 10 corresponded to changes in the amino acid polarity. These 53 mutations correspond to 17 haplotypes, of these 6 were shared and 11 were scored only once. A major shared haplotype was observed among 44 accessions of O. rufipogon along with Vandana and Kasalath. Out of 17 haplotypes, accessions representing 8 haplotypes were grown under the phosphorus-deficient conditions in hydroponics for 60 days. Significant differences were observed in the root length and weight among all the genotypes when grown under phosphorus deficiency conditions as compared to the phosphorus sufficient conditions. The O. rufipogon accession IRGC 106506 from Laos performed significantly better, with 2.5 times higher root weight and phosphorus content as compared to the positive control

Guiding phosphorus stewardship for multiple ecosystem services

USDA-ARS?s Scientific Manuscript database

Phosphorus is vital to agricultural production and water quality regulation. While the role of phosphorus in agriculture and water quality has been studied for decades, the benefits of sustainable phosphorus use and management for society due to its downstream impacts on multiple ecosystem services...

Benthic phosphorus regeneration in the Potomac River Estuary

USGS Publications Warehouse

Callender, E.

1982-01-01

The flux of dissolved reactive phosphate from Potomac riverine and estuarine sediments is controlled by processes occurring at the water-sediment interface and within surficial sediment. In situ benthic fluxes (0.1 to 2.0 mmoles m-2 day-1) are generally five to ten times higher than calculated diffusive fluxes (0.020 to 0.30 mmoles m-2 day-1). The discrepancy between the two flux estimates is greatest in the transition zone (river mile 50 to 70) and is attributd to macrofaunal irrigation. Both in situ and diffusive fluxes of dissolved reactive phosphate from Potomac tidal river sediments are low while those from anoxic lower estuarine sediments are high. The net accumulation rate of phosphorus in benthic sediment exhibits an inverse pattern. Thus a large fraction of phosphorus is retained by Potomac tidal river sediments, which contain a surficial oxidized layer and oligochaete worms tolerant of low oxygen conditions, and a large fraction of phosphorus is released from anoxic lower estuary sediments. Tidal river sediment pore waters are in equilibrium with amorphous Fe (OH)3 while lower estuary pore waters are significantly undersaturated with respect to this phase. Benthic regeneration of dissolved reactive phosphorus is sufficient to supply all the phosphorus requirements for net primary production in the lower tidal river and transition-zone waters of the Potomac River Estuary. Benthic regeneration supplies approximately 25% as much phosphorus as inputs from sewage treatment plants and 10% of all phosphorus inputs to the tidal Potomac River. When all available point source phosphorus data are put into a steady-state conservation of mass model and reasonable coefficients for uptake of dissolved phosphorus, remineralization of particulate phosphorus, and sedimentation of particulate phosphorus are used in the model, a reasonably accurate simulation of dissolved and particulate phosphorus in the water column is obtained for the summer of 1980. ?? 1982 Dr W. Junk

The New Nordic Diet: phosphorus content and absorption.

PubMed

Salomo, Louise; Poulsen, Sanne K; Rix, Marianne; Kamper, Anne-Lise; Larsen, Thomas M; Astrup, Arne

2016-04-01

High phosphorus content in the diet may have adverse effect on cardiovascular health. We investigated whether the New Nordic Diet (NND), based mainly on local, organic and less processed food and large amounts of fruit, vegetables, wholegrain and fish, versus an Average Danish Diet (ADD) would reduce the phosphorus load due to less phosphorus-containing food additives, animal protein and more plant-based proteins. Phosphorus and creatinine were measured in plasma and urine at baseline, week 12 and week 26 in 132 centrally obese subjects with normal renal function as part of a post hoc analysis of data acquired from a 26-week controlled trial. We used the fractional phosphorus excretion as a measurement of phosphorus absorption. Mean baseline fractional phosphorus excretion was 20.9 ± 6.6 % in the NND group (n = 82) and 20.8 ± 5.5 % in the ADD group (n = 50) and was decreased by 2.8 ± 5.1 and 3.1 ± 5.4 %, respectively, (p = 0.6) at week 26. At week 26, the mean change in plasma phosphorus was 0.04 ± 0.12 mmol/L in the NND group and -0.03 ± 0.13 mmol/L in the ADD group (p = 0.001). Mean baseline phosphorus intake was 1950 ± 16 mg/10 MJ in the NND group and 1968 ± 22 mg/10 MJ in the ADD group and decreased less in the NND compared to the ADD (67 ± 36 mg/10 MJ and -266 ± 45 mg/day, respectively, p < 0.298). Contrary to expectations, the NND had a high phosphorus intake and did not decrease the fractional phosphorus excretion compared with ADD. Further modifications of the diet are needed in order to make this food concept beneficial regarding phosphorus absorption.

49 CFR 173.188 - White or yellow phosphorus.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false White or yellow phosphorus. 173.188 Section 173... Class 7 § 173.188 White or yellow phosphorus. Phosphorus, white or yellow, when offered for... pound) of phosphorus with screw-top closures; or (2) Steel drums (1A1) not over 250 L (66 gallons...

49 CFR 173.188 - White or yellow phosphorus.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 2 2011-10-01 2011-10-01 false White or yellow phosphorus. 173.188 Section 173... Class 7 § 173.188 White or yellow phosphorus. Phosphorus, white or yellow, when offered for... pound) of phosphorus with screw-top closures; or (2) Steel drums (1A1) not over 250 L (66 gallons...

Relative coronal abundances derived from X-ray observations 3: The effect of cascades on the relative intensity of Fe (XVII) line fluxes, and a revised iron abundance

NASA Technical Reports Server (NTRS)

Walker, A. B. C., Jr.; Rugge, H. R.; Weiss, K.

1974-01-01

Permitted lines in the optically thin coronal X-ray spectrum were analyzed to find the distribution of coronal material, as a function of temperature, without special assumptions concerning coronal conditions. The resonance lines of N, O, Ne, Na, Mg, Al, Si, S, and Ar which dominate the quiet coronal spectrum below 25A were observed. Coronal models were constructed and the relative abundances of these elements were determined. The intensity in the lines of the 2p-3d transitions near 15A was used in conjunction with these coronal models, with the assumption of coronal excitation, to determine the Fe XVII abundance. The relative intensities of the 2p-3d Fe XVII lines observed in the corona agreed with theoretical prediction. Using a more complete theoretical model, and higher resolution observations, a revised calculation of iron abundance relative to hydrogen of 0.000026 was made.

Biomass recycling and Earth’s early phosphorus cycle

PubMed Central

Kipp, Michael A.; Stüeken, Eva E.

2017-01-01

Phosphorus sets the pace of marine biological productivity on geological time scales. Recent estimates of Precambrian phosphorus levels suggest a severe deficit of this macronutrient, with the depletion attributed to scavenging by iron minerals. We propose that the size of the marine phosphorus reservoir was instead constrained by muted liberation of phosphorus during the remineralization of biomass. In the modern ocean, most biomass-bound phosphorus gets aerobically recycled; but a dearth of oxidizing power in Earth’s early oceans would have limited the stoichiometric capacity for remineralization, particularly during the Archean. The resulting low phosphorus concentrations would have substantially hampered primary productivity, contributing to the delayed rise of atmospheric oxygen. PMID:29202032

Development of the nowcasting system for the XVII Asiad at Korea Meteorological Administration

NASA Astrophysics Data System (ADS)

Park, Kyungjeen; Kim, Juwon; Jang, Taekyu; Hwang, Seung On; Park, Yunho; Kim, Yoonjae; Park, Seonjoo; Joo, Sangwon; Noh, Hae Mi

2014-05-01

The XVII Asiad, known as the 2014 Asian game, is the largest sporting event in Asia. It will be held in Incheon, South Korea from September 19 to October 4, with 437 events in 36 sports. To support this game, Korea Meteorological Administration developed Incheon Data Assimilation and Prediction System (IDAPS) for nowcasting and very short range forecasts. The domain is centered at Incheon city and covers the central region of the Korean peninsula and adjacent seas. It repeats analysis and forecast processes with 1 hour cycling interval. IDAPS has approximately 1 km horizontal resolution with 324 x 360 grids and 70 vertical layers. Three dimensional variational data assimilation is applied to assimilate AWS, windprofiler, buoy, sonde, aircraft, scatwinds, rain rate, and radar products. The details of IDAPS and the experiment results will be given during the conference.

Impact of Fish Farming on Phosphorus in Reservoir Sediments

PubMed Central

Jia, Binyang; Tang, Ya; Tian, Liyan; Franz, Leander; Alewell, Christine; Huang, Jen-How

2015-01-01

Fish farming has seriously influenced the aquatic environment in Sancha reservoir in SW China since 1985 and has been strongly restricted since 2005. Thus, phosphorus speciation in a sediment core dated between 1945 and 2010 at cm-resolution and in surface sediments from Sancha reservoir may allow us track how fish farming impacts phosphorus dynamics in lake sediments. Fish farming shifts the major binding forms of phosphorus in sediments from organic to residual phosphorus, which mostly originated from fish feed. Sorption to metal oxides and association with organic matters are important mechanisms for phosphorus immobilisation with low fish farming activities, whereas calcium-bound phosphorous had an essential contribution to sediment phosphorus increases under intensive fish framing. Notwithstanding the shifting, the aforementioned phosphorus fractions are usually inert in the lake environment, therefore changing phosphorus mobility little. The use of fish feed and water-purification reagents, the most important additives for fish farming, introduce not only phosphorus but also large amounts of sand-sized minerals such as quartz into the lake, to which phosphorus weakly sorbs. The sand-sized minerals as additional sorbents increase the pool of easily mobilisable phosphorus in sediments, which will slow down the recovery of reservoir water due to its rapid re-mobilisation. PMID:26577441

Sustainable use of phosphorus: a finite resource.

PubMed

Scholz, Roland W; Ulrich, Andrea E; Eilittä, Marjatta; Roy, Amit

2013-09-01

Phosphorus is an essential element of life and of the modern agricultural system. Today, science, policy, agro-industry and other stakeholder groups are increasingly concerned about the sustainable use of this resource, given the dissipative nature of phosphorus and difficulties in assessing, evaluating, and coping with phosphorus pollution in aquatic and terrestrial systems. We argue that predictions about a forthcoming peak, followed by a quick reduction (i.e., physical phosphate rock scarcity) are unreasoned and stress that access to phosphorus (economic scarcity) is already, and may increasingly become critical, in particular for smallholders farmers in different parts of the world. The paper elaborates on the design, development, goals and cutting-edge contributions of a global transdisciplinary process (i.e. mutual learning between science and society including multiple stakeholders) on the understanding of potential contributions and risks related to the current mode of using phosphorus on multiple scales (Global TraPs). While taking a global and comprehensive view on the whole phosphorus-supply chain, Global TraPs organizes and integrates multiple transdisciplinary case studies to better answer questions which inform sustainable future phosphorus use. Its major goals are to contribute to four issues central to sustainable resource management: i) long-term management of biogeochemical cycles, in particular the challenge of closing the phosphorus cycle, ii) achieving food security, iii) avoiding environmental pollution and iv) sustainability learning on a global level by transdisciplinary processes. Copyright © 2013 Elsevier B.V. All rights reserved.

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. Crown Copyright © 2010. Published by Elsevier B.V. All rights reserved.

Transformation of apatite phosphorus and non-apatite inorganic phosphorus during incineration of sewage sludge.

PubMed

Li, Rundong; Zhang, Ziheng; Li, Yanlong; Teng, Wenchao; Wang, Weiyun; Yang, Tianhua

2015-12-01

The recovery of phosphorus from incinerated sewage sludge ash (SSA) is assumed to be economical. Transformation from non-apatite inorganic phosphorus (NAIP) to apatite phosphorus (AP), which has a higher bioavailability and more extensive industrial applications, was studied at 750-950°C by sewage sludge incineration and model compound incineration with a calcium oxide (CaO) additive. Thermogravimetric differential scanning calorimetry analysis and X-ray diffraction measurements were used to analyze the reactions between NAIP with CaO and crystallized phases in SSA. High temperatures stimulated the volatilization of NAIP instead of AP. Sewage sludge incineration with CaO transformed NAIP into AP, and the percentage of AP from the total phosphorus reached 99% at 950°C. Aluminum phosphate reacted with CaO, forming Ca2P2O7 and Ca3(PO4)2 at 750-950°C. Reactions between iron phosphate and CaO occurred at lower temperatures, forming Ca(PO3)2 before reaching 850°C. Copyright © 2015 Elsevier Ltd. All rights reserved.

Phosphorus Fate and Dynamics in Greywater Biofiltration Systems.

PubMed

Fowdar, Harsha S; Hatt, Belinda E; Cresswell, Tom; Harrison, Jennifer J; Cook, Perran L M; Deletic, Ana

2017-02-21

Phosphorus, a critical environmental pollutant, is effectively removed from stormwater by biofiltration systems, mainly via sedimentation and straining. However, the fate of dissolved inflow phosphorus concentrations in these systems is unknown. Given the growing interest in using biofiltration systems to treat other polluted waters, for example greywater, such an understanding is imperative to optimize designs for successful long-term performance. A mass balance method and a radiotracer, 32 P (as H 3 PO 4 ), were used to investigate the partitioning of phosphorus (concentrations of 2.5-3.5 mg/L, >80% was in dissolved inorganic form) between the various biofilter components at the laboratory scale. Planted columns maintained a phosphorus removal efficiency of >95% over the 15-week study period. Plant storage was found to be the dominant phosphorus sink (64% on average). Approximately 60% of the phosphorus retained in the filter media was recovered in the top 0-6 cm. The 32 P tracer results indicate that adsorption is the immediate primary fate of dissolved phosphorus in the system (up to 57% of input P). Plant assimilation occurs at other times, potentially liberating sorption sites for processing of subsequent incoming phosphorus. Plants with high nutrient uptake capacities and the ability to efficiently extract soil phosphorus, for example Carex appressa, are, thus, recommended for use in greywater biofilters.

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.

Measurement of the radiative decay and energy of the metastable $${(2{s}^{2}2{p}_{1/2}^{5}3{s}_{1/2})}_{(J=0)}$$ level in Fe XVII

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beiersdorfer, P.; Lopez-Urrutia, J. R. Crespo; Trabert, E.

Measurements at the Livermore electron beam ion trap have been performed in order to infer the energy and the radiative lifetime of themore » $${(1{s}^{2}2{s}^{2}2{p}_{1/2}^{5}3{s}_{1/2})}_{J=0}$$ level in the Fe xvii spectrum. This is the longest-lived level in the neonlike iron ion, and its radiative decay produces the Fe xvii line at 1153 Å, feeding the population of the $${(1{s}^{2}2{s}^{2}2{p}_{3/2}^{5}3{s}_{1/2})}_{J=1}$$ upper level of one of the most prominent lines in the Fe xvii L-shell X-ray spectrum, commonly dubbed $3G$. In the presence of a strong ($$\\geqslant $$ few kG) magnetic field, the $${(1{s}^{2}2{s}^{2}2{p}_{1/2}^{5}3{s}_{1/2})}_{J=0}$$ level has a finite probability to decay directly to the $${(1{s}^{2}2{s}^{2}2{p}^{6})}_{J=0}$$ neonlike ground level via the emission of an L-shell X-ray. Our measurements allow us to observe this X-ray line in the Fe xvii L-shell spectrum and from it to infer the radiative rate for the magnetic dipole decay of the $${(1{s}^{2}2{s}^{2}2{p}_{1/2}^{5}3{s}_{1/2})}_{J=0}$$ level to the $${(1{s}^{2}2{s}^{2}2{p}_{3/2}^{5}3{s}_{1/2})}_{J=1}$$. Our result of $$(1.45\\pm 0.15)\\times {10}^{4}$$ s-1 is in agreement with predictions. We have also measured the wavelength of the associated X-ray line to be 16.804 ± 0.002 Å, which means that the line is displaced 1.20 ± 0.05 eV from the neighboring $${(2{s}^{2}2{p}_{1/2}^{5}3{s}_{1/2})}_{J=1}\\to {(2{s}^{2}2{p}^{6})}_{J=0}$$ transition, commonly labeled $3F$. Furthermore, from our measurement, we infer 5950570 ± 710 cm-1 for the energy of the $${(1{s}^{2}2{s}^{2}2{p}_{1/2}^{5}3{s}_{1/2})}_{J=0}$$ level.« less

Measurement of the radiative decay and energy of the metastable $${(2{s}^{2}2{p}_{1/2}^{5}3{s}_{1/2})}_{(J=0)}$$ level in Fe XVII

DOE PAGES

Beiersdorfer, P.; Lopez-Urrutia, J. R. Crespo; Trabert, E.

2016-01-20

Measurements at the Livermore electron beam ion trap have been performed in order to infer the energy and the radiative lifetime of themore » $${(1{s}^{2}2{s}^{2}2{p}_{1/2}^{5}3{s}_{1/2})}_{J=0}$$ level in the Fe xvii spectrum. This is the longest-lived level in the neonlike iron ion, and its radiative decay produces the Fe xvii line at 1153 Å, feeding the population of the $${(1{s}^{2}2{s}^{2}2{p}_{3/2}^{5}3{s}_{1/2})}_{J=1}$$ upper level of one of the most prominent lines in the Fe xvii L-shell X-ray spectrum, commonly dubbed $3G$. In the presence of a strong ($$\\geqslant $$ few kG) magnetic field, the $${(1{s}^{2}2{s}^{2}2{p}_{1/2}^{5}3{s}_{1/2})}_{J=0}$$ level has a finite probability to decay directly to the $${(1{s}^{2}2{s}^{2}2{p}^{6})}_{J=0}$$ neonlike ground level via the emission of an L-shell X-ray. Our measurements allow us to observe this X-ray line in the Fe xvii L-shell spectrum and from it to infer the radiative rate for the magnetic dipole decay of the $${(1{s}^{2}2{s}^{2}2{p}_{1/2}^{5}3{s}_{1/2})}_{J=0}$$ level to the $${(1{s}^{2}2{s}^{2}2{p}_{3/2}^{5}3{s}_{1/2})}_{J=1}$$. Our result of $$(1.45\\pm 0.15)\\times {10}^{4}$$ s-1 is in agreement with predictions. We have also measured the wavelength of the associated X-ray line to be 16.804 ± 0.002 Å, which means that the line is displaced 1.20 ± 0.05 eV from the neighboring $${(2{s}^{2}2{p}_{1/2}^{5}3{s}_{1/2})}_{J=1}\\to {(2{s}^{2}2{p}^{6})}_{J=0}$$ transition, commonly labeled $3F$. Furthermore, from our measurement, we infer 5950570 ± 710 cm-1 for the energy of the $${(1{s}^{2}2{s}^{2}2{p}_{1/2}^{5}3{s}_{1/2})}_{J=0}$$ level.« less

Sustainable Phosphorus Chemistry: A Silylphosphide Synthon for the Generation of Value-Added Phosphorus Chemicals.

PubMed

Slootweg, J Chris

2018-05-07

Avoiding white phosphorus: Cummins and Geeson have recently described the conversion of phosphoric acid into the novel bis(trichlorosilyl)phosphide anion, which serves as a key intermediate in the synthesis of organophosphines, hexafluorophosphate, and phosphine gas in a reaction sequence that does not rely on white phosphorus. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

40 CFR 422.20 - Applicability; description of the phosphorus consuming subcategory.

Code of Federal Regulations, 2011 CFR

2011-07-01

... phosphorus consuming subcategory. 422.20 Section 422.20 Protection of Environment ENVIRONMENTAL PROTECTION... Phosphorus Consuming Subcategory § 422.20 Applicability; description of the phosphorus consuming subcategory... manufacture of phosphoric acid, phosphorus pentoxide, phosphorus pentasulfide, phosphorus trichloride, and...

40 CFR 422.20 - Applicability; description of the phosphorus consuming subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... phosphorus consuming subcategory. 422.20 Section 422.20 Protection of Environment ENVIRONMENTAL PROTECTION... Phosphorus Consuming Subcategory § 422.20 Applicability; description of the phosphorus consuming subcategory... manufacture of phosphoric acid, phosphorus pentoxide, phosphorus pentasulfide, phosphorus trichloride, and...

Preliminary analysis of phosphorus flow in Hue Citadel.

PubMed

Anh, T N Q; Harada, H; Fujii, S; Anh, P N; Lieu, P K; Tanaka, S

2016-01-01

Characteristics of waste and wastewater management can affect material flows. Our research investigates the management of waste and wastewater in urban areas of developing countries and its effects on phosphorus flow based on a case study in Hue Citadel, Hue, Vietnam. One hundred households were interviewed to gain insight into domestic waste and wastewater management together with secondary data collection. Next, a phosphorus flow model was developed to quantify the phosphorus input and output in the area. The results showed that almost all wastewater generated in Hue Citadel was eventually discharged into water bodies and to the ground/groundwater. This led to most of the phosphorus output flowing into water bodies (41.2 kg P/(ha year)) and ground/groundwater (25.3 kg P/(ha year)). Sewage from the sewer system was the largest source of phosphorus loading into water bodies, while effluent from on-site sanitation systems was responsible for a major portion of phosphorus into the ground/groundwater. This elevated phosphorus loading is a serious issue in considering surface water and groundwater protection.

Soil Phosphorus and the Ecology of Tropical Forests

NASA Astrophysics Data System (ADS)

Turner, B. L.

2016-12-01

Phosphorus availability is commonly assumed to limit forest productivity on strongly weathered soils in the lowland tropics, but experimental evidence is scarce and equivocal. In this presentation I will explore the extent to which phosphorus influences the productivity and distribution of tree species in tropical forests. I will highlight the range of soils that occur in tropical forests and the associated variation in the amounts and forms of soil phosphorus. I will draw on data from a regional-scale network of forest dynamics plots in Panama to show that tree species distributions are determined primarily by dry season intensity and soil phosphorus availability. Finally, I will demonstrate that phosphorus limitation of tropical tree growth is widespread at the level of individual species, but is not observed at the community level in diverse forests due to species turnover across phosphorus gradients.

[Research advances in mechanism of high phosphorus use efficiency of plants].

PubMed

Ma, Xiangqing; Liang, Xia

2004-04-01

Phosphorus deficiency is one of the main factors influencing agricultural and forestry productions. Fertilization and soil improvement are the major measures to meet the demand of phosphorus for crops in traditional agriculture and forestry management. Recently, the plants with high phosphorus use efficiency have been discovered to replace the traditional measures to improve phosphorus use efficiency of crops. This paper reviewed the research advances in the morphological, physiological and genetics mechanisms of plants with high phosphorus use efficiency. There were three mechanisms for the plants with high phosphorus use efficiency to grow under phosphorus stress: (1) under low phosphorus stress, the root morphology would change (root system grew fast, root axes became small, the number and density of lateral root increased) and more photosynthesis products would transport from the crown to the root, (2) under low phosphorus stress, plant root exudation increased, mycorrhizae invaded into root system, the feature of root absorption kinetics changed, and the internal phosphorus cycling of plant reinforced to tolerate phosphorus deficiency, and (3) under long selection stress of low phosphorus, some plants would form the genetic properties of phosphorus nutrition that could exploit the hardly soluble phosphorus in the soil.

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

Effects of systematic nursing instruction on a low-phosphorus diet, serum phosphorus level and pruritus of patients on haemodialysis.

PubMed

Cheng, Ting-Yin; Tarng, Der-Cherng; Liao, Yuan-Mei; Lin, Pi-Chu

2017-02-01

To investigate the effectiveness of systematic nursing instruction on a low-phosphorus diet, serum phosphorus level and pruritus of haemodialysis patients. A high number of end-stage renal disease patients on haemodialysis are bothered by pruritus. Hyperphosphataemia was reported to be related to pruritus. An experimental design was applied. Ninety-four patients who received haemodialysis between September 2013 and December 2013 at a medical centre in Taipei, Taiwan, were recruited. An experimental group received individual systematic nursing instruction by the investigator through a nursing instruction pamphlet and reminder card for taking medication. A control group received traditional nursing instruction. The pruritus, blood phosphorus level and five-day diet records were evaluated before and after intervention. The experimental group had a low-phosphorus diet intake compared with the control group (p < 0·001). A significant difference in serum phosphorus level was observed between the experimental and control groups (p = 0·002). Incidence of pruritus was lower in the experimental group than in the control group (p < 0·001). A systematic nursing instruction included using a pamphlet, pictures and reminder cards, the patients' blood phosphorus levels decreased, the patients consumed more low-phosphorus food, and pruritus decreased. This study recommends that clinical nursing staff include systematic nursing instruction as a routine practice for dialysis patients. © 2016 John Wiley & Sons Ltd.

Soil phosphorus dynamics under sprinkler and furrow irrigation

USDA-ARS?s Scientific Manuscript database

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...

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

Management of Natural and Added Dietary Phosphorus Burden in Kidney Disease

PubMed Central

Cupisti, Adamasco; Kalantar-Zadeh, Kamyar

2018-01-01

Phosphorus retention occurs from higher dietary phosphorus intake relative to its renal excretion or dialysis removal. In the gastrointestinal tract the naturally existing organic phosphorus is only partially (~60%) absorbable; however, this absorption varies widely and is lower for plant-based phosphorus including phytate (<40%) and higher for foods enhanced with inorganic-phosphorus-containing preservatives (>80%). The latter phosphorus often remains unrecognized by patients and health care professionals, even though it is widely used in contemporary diets, in particular low-cost foods. In a non-enhanced mixed diet, the digestible phosphorus is closely correlated with total protein content, making protein-rich foods a main source of natural phosphorus. Phosphorus burden is more appropriately limited in pre-dialysis patients who are on low protein diets (~0.6 g/kg/day), whereas dialysis patients who require higher protein intake (~1.2 g/kg/day) are subject to a higher dietary phosphorus load. An effective and patient-friendly approach to reduce phosphorus intake without depriving patients of adequate proteins is to educate patients to avoid foods with high phosphorus relative to protein such as egg yolk and those with high amounts of phosphorus-based preservatives such as certain soft drinks and enhanced cheese and meat. Protein-rich foods should be prepared by boiling, which reduces phosphorus as well as sodium and potassium content, or by other types of cooking induced demineralization. The dose of phosphorus-binding therapy should be adjusted separately for the amount and absorbability of phosphorus in each meal. Dietician counselling to address the foregoing aspects of dietary phosphorus management is instrumental for achieving reduction of phosphorus load. PMID:23465504

phosphorus retention data and metadata

EPA Pesticide Factsheets

phosphorus retention in wetlands data and metadataThis dataset is associated with the following publication:Lane , C., and B. Autrey. Phosphorus retention of forested and emergent marsh depressional wetlands in differing land uses in Florida, USA. Wetlands Ecology and Management. Springer Science and Business Media B.V;Formerly Kluwer Academic Publishers B.V., GERMANY, 24(1): 45-60, (2016).

Electrically-inactive phosphorus re-distribution during low temperature annealing

NASA Astrophysics Data System (ADS)

Peral, Ana; Youssef, Amanda; Dastgheib-Shirazi, Amir; Akey, Austin; Peters, Ian Marius; Hahn, Giso; Buonassisi, Tonio; del Cañizo, Carlos

2018-04-01

An increased total dose of phosphorus (P dose) in the first 40 nm of a phosphorus diffused emitter has been measured after Low Temperature Annealing (LTA) at 700 °C using the Glow Discharge Optical Emission Spectrometry technique. This evidence has been observed in three versions of the same emitter containing different amounts of initial phosphorus. A stepwise chemical etching of a diffused phosphorus emitter has been carried out to prepare the three types of samples. The total P dose in the first 40 nm increases during annealing by 1.4 × 1015 cm-2 for the sample with the highly doped emitter, by 0.8 × 1015 cm-2 in the middle-doped emitter, and by 0.5 × 1015 cm-2 in the lowest-doped emitter. The presence of surface dislocations in the first few nanometers of the phosphorus emitter might play a role as preferential sites of local phosphorus gettering in phosphorus re-distribution, because the phosphorus gettering to the first 40 nm is lower when this region is etched stepwise. This total increase in phosphorus takes place even though the calculated electrically active phosphorus concentration shows a reduction, and the measured sheet resistance shows an increase after annealing at a low temperature. The reduced electrically active P dose is around 0.6 × 1015 cm-2 for all the emitters. This can be explained with phosphorus-atoms diffusing towards the surface during annealing, occupying electrically inactive configurations. An atomic-scale visual local analysis is carried out with needle-shaped samples of tens of nm in diameter containing a region of the highly doped emitter before and after LTA using Atom Probe Tomography, showing phosphorus precipitates of 10 nm and less before annealing and an increased density of larger precipitates after annealing (25 nm and less).

21 CFR 862.1580 - Phosphorus (inorganic) test system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Phosphorus (inorganic) test system. 862.1580... (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1580 Phosphorus (inorganic) test system. (a) Identification. A phosphorus (inorganic) test...

21 CFR 862.1580 - Phosphorus (inorganic) test system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Phosphorus (inorganic) test system. 862.1580... (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1580 Phosphorus (inorganic) test system. (a) Identification. A phosphorus (inorganic) test...

Ocean acidification: One potential driver of phosphorus eutrophication.

PubMed

Ge, Changzi; Chai, Yanchao; Wang, Haiqing; Kan, Manman

2017-02-15

Harmful algal blooms which may be limited by phosphorus outbreak increases currently and ocean acidification worsens presently, which implies that ocean acidification might lead to phosphorus eutrophication. To verify the hypothesis, oxic sediments were exposed to seawater with different pH 30days. If pH was 8.1 and 7.7, the total phosphorus (TP) content in sediments was 1.52±0.50 and 1.29±0.40mg/g. The inorganic phosphorus (IP) content in sediments exposed to seawater with pH8.1 and 7.7 was 1.39±0.10 and 1.06±0.20mg/g, respectively. The exchangeable phosphorus (Ex-P) content in sediments was 4.40±0.45 and 2.82±0.15μg/g, if seawater pH was 8.1 and 7.7. Ex-P and IP contents in oxic sediments were reduced by ocean acidification significantly (p<5%). The reduced phosphorus in sediments diffused into water, which implied that ocean acidification was one potential facilitator of phosphorus eutrophication in oxic conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Infrared fingerprints of few-layer black phosphorus

PubMed Central

Zhang, Guowei; Huang, Shenyang; Chaves, Andrey; Song, Chaoyu; Özçelik, V. Ongun; Low, Tony; Yan, Hugen

2017-01-01

Black phosphorus is an infrared layered material. Its bandgap complements other widely studied two-dimensional materials: zero-gap graphene and visible/near-infrared gap transition metal dichalcogenides. Although highly desirable, a comprehensive infrared characterization is still lacking. Here we report a systematic infrared study of mechanically exfoliated few-layer black phosphorus, with thickness ranging from 2 to 15 layers and photon energy spanning from 0.25 to 1.36 eV. Each few-layer black phosphorus exhibits a thickness-dependent unique infrared spectrum with a series of absorption resonances, which reveals the underlying electronic structure evolution and serves as its infrared fingerprints. Surprisingly, unexpected absorption features, which are associated with the forbidden optical transitions, have been observed. Furthermore, we unambiguously demonstrate that controllable uniaxial strain can be used as a convenient and effective approach to tune the electronic structure of few-layer black phosphorus. Our study paves the way for black phosphorus applications in infrared photonics and optoelectronics. PMID:28059084

Infrared fingerprints of few-layer black phosphorus.

PubMed

Zhang, Guowei; Huang, Shenyang; Chaves, Andrey; Song, Chaoyu; Özçelik, V Ongun; Low, Tony; Yan, Hugen

2017-01-06

Black phosphorus is an infrared layered material. Its bandgap complements other widely studied two-dimensional materials: zero-gap graphene and visible/near-infrared gap transition metal dichalcogenides. Although highly desirable, a comprehensive infrared characterization is still lacking. Here we report a systematic infrared study of mechanically exfoliated few-layer black phosphorus, with thickness ranging from 2 to 15 layers and photon energy spanning from 0.25 to 1.36 eV. Each few-layer black phosphorus exhibits a thickness-dependent unique infrared spectrum with a series of absorption resonances, which reveals the underlying electronic structure evolution and serves as its infrared fingerprints. Surprisingly, unexpected absorption features, which are associated with the forbidden optical transitions, have been observed. Furthermore, we unambiguously demonstrate that controllable uniaxial strain can be used as a convenient and effective approach to tune the electronic structure of few-layer black phosphorus. Our study paves the way for black phosphorus applications in infrared photonics and optoelectronics.

Phosphorus allotropes: Stability of black versus red phosphorus re-examined by means of the van der Waals inclusive density functional method

NASA Astrophysics Data System (ADS)

Aykol, Muratahan; Doak, Jeff W.; Wolverton, C.

2017-06-01

We evaluate the energetic stabilities of white, red, and black allotropes of phosphorus using density functional theory (DFT) and hybrid functional methods, van der Waals (vdW) corrections (DFT+vdW and hybrid+vdW), vdW density functionals, and random phase approximation (RPA). We find that stability of black phosphorus over red-V (i.e., the violet form) is not ubiquitous among these methods, and the calculated enthalpies for the reaction phosphorus (red-V)→phosphorus (black) are scattered between -20 and 40 meV/atom. With local density and generalized gradient approximations, and hybrid functionals, mean absolute errors (MAEs) in densities of P allotropes relative to experiments are found to be around 10%-25%, whereas with vdW-inclusive methods, MAEs in densities drop below ˜5 %. While the inconsistency among the density functional methods could not shed light on the stability puzzle of black versus red phosphorus, comparison of their accuracy in predicting densities and the supplementary RPA results on relative stabilities indicate that opposite to the common belief, black and red phosphorus are almost degenerate, or the red-V (violet) form of phosphorus might even be the ground state.

Phosphorus sorption-desorption and effects of temperature, pH and salinity on phosphorus sorption in marsh soils from coastal wetlands with different flooding conditions.

PubMed

Bai, Junhong; Ye, Xiaofei; Jia, Jia; Zhang, Guangliang; Zhao, Qingqing; Cui, Baoshan; Liu, Xinhui

2017-12-01

Wetland soils act as a sink or source of phosphorus (P) to the overlaying water due to phosphorus sorption-desorption processes. Litter information is available on sorption and desorption behaviors of phosphorus in coastal wetlands with different flooding conditions. Laboratory experiments were conducted to investigate phosphorus sorption-desorption processes, fractions of adsorbed phosphorus, and the effects of salinity, pH and temperature on phosphorus sorption on soils in tidal-flooding wetlands (TW), freshwater-flooding wetlands (FW) and seasonal-flooding wetlands (SW) in the Yellow River Delta. Our results showed that the freshly adsorbed phosphorus dominantly exists in Occluded-P and Fe/AlP and their percentages increased with increasing phosphorus adsorbed. Phosphorus sorption isotherms could be better described by the modified Langmuir model than by the modified Freundlich model. A binomial equation could be properly used to describe the effects of salinity, pH, and temperature on phosphorus sorption. Phosphorus sorption generally increased with increasing salinity, pH, and temperature at lower ranges, while decreased in excess of some threshold values. The maximum phosphorus sorption capacity (Q max ) was larger for FW soils (256 mg/kg) compared with TW (218 mg/kg) and SW soils (235 mg/kg) (p < 0.05). The percentage of phosphorus desorption (P des ) in the FW soils (7.5-63.5%) was much lower than those in TW (27.7-124.9%) and SW soils (19.2-108.5%). The initial soil organic matter, pH and the exchangeable Al, Fe and Cd contents were important factors influencing P sorption and desorption. The findings of this study indicate that freshwater restoration can contribute to controlling the eutrophication status of water bodies through increasing P sorption. Copyright © 2017 Elsevier Ltd. All rights reserved.

The study of Phosphorus distribution at Putrajaya Wetland

NASA Astrophysics Data System (ADS)

Mubin Zahari, Nazirul; Malek, Nur Farzana Fasiha Abdul; Fai, Chow Ming; Humaira Haron, Siti; Hafiz Zawawi, Mohd; Nazmi Ismail, Iszmir; Mohamad, Daud; Syamsir, Agusril; Sidek, Lariyah Mohd; Zakwan Ramli, Mohd; Ismail, Norfariza; Zubir Sapian, Ahmad; Noordin, Normaliza; Rahaman, Nurliyana Abdul; Muhamad, Yahzam; Mat Saman, Jarina

2018-04-01

This study is concerning phosphorus distribution in Putrajaya Wetland. Phosphorus is one of the important component in nutrients for living things be it aquatic or non – aquatic organisms. Total phosphorus (TP) results will give some information on the trophic status of surface water in water bodies. The focus of this study is to determine the total phosphorus concentration in Putrajaya Wetland which is in the inlet of the wetland then outlet of the wetland (Central Wetland Lake). The water sample is taken from Putrajaya Wetland and the test was conducted in the laboratory. The result from this study shows the results for total phosphorus according to month, sampling station and cells. Lowest total phosphate at the Central Wetland compare with all the wetland arms cells.

77 FR 46298 - Phosphorus Water Quality Standards for Florida Everglades

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-03

... Phosphorus Water Quality Standards for Florida Everglades AGENCY: Environmental Protection Agency (EPA... Quality Standards for Phosphorus in the Everglades Protection Area (Phosphorus Rule) and Florida's Amended... deficiencies in the Phosphorus Rule and EFA. EPA's disapproval, specific directions to the State, and this rule...

Seedling growth responses to phosphorus reflect adult distribution patterns of tropical trees.

PubMed

Zalamea, Paul-Camilo; Turner, Benjamin L; Winter, Klaus; Jones, F Andrew; Sarmiento, Carolina; Dalling, James W

2016-10-01

Soils influence tropical forest composition at regional scales. In Panama, data on tree communities and underlying soils indicate that species frequently show distributional associations to soil phosphorus. To understand how these associations arise, we combined a pot experiment to measure seedling responses of 15 pioneer species to phosphorus addition with an analysis of the phylogenetic structure of phosphorus associations of the entire tree community. Growth responses of pioneers to phosphorus addition revealed a clear tradeoff: species from high-phosphorus sites grew fastest in the phosphorus-addition treatment, while species from low-phosphorus sites grew fastest in the low-phosphorus treatment. Traits associated with growth performance remain unclear: biomass allocation, phosphatase activity and phosphorus-use efficiency did not correlate with phosphorus associations; however, phosphatase activity was most strongly down-regulated in response to phosphorus addition in species from high-phosphorus sites. Phylogenetic analysis indicated that pioneers occur more frequently in clades where phosphorus associations are overdispersed as compared with the overall tree community, suggesting that selection on phosphorus acquisition and use may be strongest for pioneer species with high phosphorus demand. Our results show that phosphorus-dependent growth rates provide an additional explanation for the regional distribution of tree species in Panama, and possibly elsewhere. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Phosphorus, a key to life on the primitive earth

NASA Technical Reports Server (NTRS)

Griffith, E. J.; Ponnamperuma, C.; Gabel, N. W.

1977-01-01

The phosphorus of the primitive earth was present as phosphates. It is strongly probable that a portion of the phosphate was present as condensed phosphates. The primitive earth was highly deficient in the total available phosphorus until a sufficient quantity of phosphorus weathered from the igneous rocks in which it was entrapped. Approximately three billion years were required for the seas to become saturated. Until this time passed the seas acted as a giant sink for phosphorus, diluting it to the extent that all forms of life were deprived of the vital nutrient. When the seas became saturated, the rate of turnover of the phosphorus increased rapidly. As the seas pulsated, they left the excess precipitate phosphorus as sedimentary rock in locally rich deposits on which life could thrive.

76 FR 38592 - Phosphorus Water Quality Standards for Florida Everglades

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-01

... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 131 [EPA-HQ-OW-2011-0515; FRL-9428-3] Phosphorus Water... Standards for Phosphorus in the Everglades Protection Area (Phosphorus Rule) and Florida's Amended... the Phosphorus Rule and EFA. EPA's disapproval, specific directions to the State, and today's proposed...

Recovery of phosphorus compounds from thermally-processed wastes

NASA Astrophysics Data System (ADS)

Czechowska-Kosacka, A.; Pawłowski, L.; Niedbala, G.; Cel, W.

2018-05-01

Depletion of phosphorus deposits is one of the most serious global problems, which may soon lead to a crisis in food production. It is estimated that if the current living standard is maintained, the available reserves will be depleted in 130 years. Considering the principle of sustainable development, searching for alternative phosphorus sources is extremely important. The work presented the results of the research on the possibility of utilizing wastes as a source of phosphorus. The studies were conducted on poultry manure. The physicochemical properties of phosporus-rich wastes were determined as well. The fertilizing properties of ashes from poultry manure combustion – obtained from different systems, i.e. caged and barn production. The assimilability of phosphorus from the obtained ashes was determined. Potential applications of phosphorus-rich ashes were proposed as well.

Doping-stabilized two-dimensional black phosphorus.

PubMed

Xuan, Xiaoyu; Zhang, Zhuhua; Guo, Wanlin

2018-05-03

Two-dimensional (2D) black phosphorus (BP) has attracted broad interests but remains to be synthesized. One of the issues lies in its large number of 2D allotropes with highly degenerate energies, especially 2D blue phosphorus. Here, we show that both nitrogen and hole-carrier doping can lift the energy degeneracy and locate 2D BP in a deep global energy minimum, while arsenic doping favours the formation of 2D blue phosphorus, attributed to a delicate interplay between s-p overlapping and repulsion of lone pairs. Chemically inert substrates, e.g. graphene and hexagonal boron nitride, can be synergic with carrier doping to stabilize the BP further over other 2D allotropes, while frequently used metal substrates severely reduce the stability of 2D BP. These results not only offer new insight into the structural stability of 2D phosphorus but also suggest a promising pathway towards the chemical synthesis of 2D BP.

Decay Properties of K-Vacancy States in Fe X-Fe XVII

NASA Technical Reports Server (NTRS)

Mendoza, C.; Kallman, T. R.; Bautista, M. A.; Palmeri, P.

2003-01-01

We report extensive calculations of the decay properties of fine-structure K-vacancy levels in Fe X-Fe XVII. A large set of level energies, wavelengths, radiative and Auger rates, and fluorescence yields has been computed using three different standard atomic codes, namely Cowan's HFR, AUTOSTRUCTURE and the Breit-Pauli R-matrix package. This multi-code approach is used to the study the effects of core relaxation, configuration interaction and the Breit interaction, and enables the estimate of statistical accuracy ratings. The Ksigma and KLL Auger widths have been found to be nearly independent of both the outer-electron configuration and electron occupancy keeping a constant ratio of 1.53 +/- 0.06. By comparing with previous theoretical and measured wavelengths, the accuracy of the present set is determined to be within 2 m Angstrom. Also, the good agreement found between the different radiative and Auger data sets that have been computed allow us to propose with confidence an accuracy rating of 20% for the line fluorescence yields greater than 0.01. Emission and absorption spectral features are predicted finding good correlation with measurements in both laboratory and astrophysical plasmas.

Calcium and phosphorus requirements of breeding bobwhite quail

USGS Publications Warehouse

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

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.

White phosphorus

Integrated Risk Information System (IRIS)

White phosphorus ; CASRN 7723 - 14 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic

The effects of phosphorus limitation on carbon metabolism in diatoms.

PubMed

Brembu, Tore; Mühlroth, Alice; Alipanah, Leila; Bones, Atle M

2017-09-05

Phosphorus is an essential element for life, serving as an integral component of nucleic acids, lipids and a diverse range of other metabolites. Concentrations of bioavailable phosphorus are low in many aquatic environments. Microalgae, including diatoms, apply physiological and molecular strategies such as phosphorus scavenging or recycling as well as adjusting cell growth in order to adapt to limiting phosphorus concentrations. Such strategies also involve adjustments of the carbon metabolism. Here, we review the effect of phosphorus limitation on carbon metabolism in diatoms. Two transcriptome studies are analysed in detail, supplemented by other transcriptome, proteome and metabolite data, to gain an overview of different pathways and their responses. Phosphorus, nitrogen and silicon limitation responses are compared, and similarities and differences discussed. We use the current knowledge to propose a suggestive model for the carbon flow in phosphorus-replete and phosphorus-limited diatom cells.This article is part of the themed issue 'The peculiar carbon metabolism in diatoms'. © 2017 The Authors.

The effects of phosphorus limitation on carbon metabolism in diatoms

PubMed Central

Alipanah, Leila

2017-01-01

Phosphorus is an essential element for life, serving as an integral component of nucleic acids, lipids and a diverse range of other metabolites. Concentrations of bioavailable phosphorus are low in many aquatic environments. Microalgae, including diatoms, apply physiological and molecular strategies such as phosphorus scavenging or recycling as well as adjusting cell growth in order to adapt to limiting phosphorus concentrations. Such strategies also involve adjustments of the carbon metabolism. Here, we review the effect of phosphorus limitation on carbon metabolism in diatoms. Two transcriptome studies are analysed in detail, supplemented by other transcriptome, proteome and metabolite data, to gain an overview of different pathways and their responses. Phosphorus, nitrogen and silicon limitation responses are compared, and similarities and differences discussed. We use the current knowledge to propose a suggestive model for the carbon flow in phosphorus-replete and phosphorus-limited diatom cells. This article is part of the themed issue ‘The peculiar carbon metabolism in diatoms’. PMID:28717016

Phosphorus adlayers on Platinum (110)

NASA Astrophysics Data System (ADS)

Heikkinen, Olli; Riihimäki, Ari; Sainio, Jani; Lahtinen, Jouko

2017-10-01

Platinum is a metal utilized in many applications. Its catalytic activity can be decreased due to chemical poisoning caused e.g. by phosphorus. To gain more understanding of its poisoning, we present a study of phosphorus adsorption on a platinum (110) single crystal surface. Using X-ray photoelectron spectroscopy, we have found that the adsorbate coverage saturates at around 3 monolayers. Annealing the phosphorus-covered platinum surface at 750 °C gives rise to three different ordered adlayer structures, with symmetries of 2 × 3, 11 × 4 and √{ 2} × 1 , from the lowest to the highest coverage, detected with low-energy electron diffraction. We have studied the sample topography with scanning tunnelling microscopy. We also present a tentative model for the observed structures and their evolution.

Phosphorus removal by electric arc furnace steel slag adsorption

NASA Astrophysics Data System (ADS)

Lim, J. W.; Lee, K. F.; Chong, Thomas S. Y.; Abdullah, L. C.; Razak, M. A.; Tezara, C.

2017-10-01

As to overcome the eutrophication in lakes and reservoirs which is resulted from excessive input of phosphorus due to rapid urbanization or uncontrolled agricultural activities, Electric Arc Furnace steel slag (EAFS), a steelmaking by-product, in which the disposal of this industrial waste considered economically unfavourable yet it’s physical and chemical properties exhibits high potential to be great P adsorbent. The objective of this study was to identify most suitable mathematical model in description of adsorption by using traditional batch experiment and to investigate the effect on Phosphorus removal efficiency and Phosphorus removal capacity by EAFS adsorption through variation of parameters such as pH, size of slag and initial concentration of Phosphorus. Result demonstrated that, Langmuir is suitable in describing Phosphorus removal mechanisms with the Maximum Adsorption Capacity, Q m of 0.166 mg/g and Langmuir Constant, KL of 0.03519 L/mg. As for effect studies, smaller size of adsorbent shows higher percentage (up to 37.8%) of Phosphorus removal compared to the larger size. Besides that, the experiment indicated a more acidic environment is favourable for Phosphorus removal and the amount of Phosphorus adsorbed at pH 3.0 was the highest. In addition, the adsorption capacity increases steadily as the initial Phosphorus concentration increases but it remained steady at 100mg P/L. Eventually, this study serves as better understanding on preliminary studies of P removal mechanisms by EAFS.

Phosphorus Moieties Make Polymers Less Flammable

NASA Technical Reports Server (NTRS)

Kourtides, D. A.; Mikroyannidis, J. A.

1992-01-01

Phosphorus incorporated into epoxies and polyamides via curing agent. According to report, use of 1-(di(2-chloroethoxyphosphinyl)methyl)-2,4- and -2,6-diaminobenzene (DCEPD) as curing agent for epoxies and polyamides makes these polymers more fire-retardant than corresponding polymers made with standard curing agents not containing phosphorus.

40 CFR 422.10 - Applicability; description of the phosphorus production subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... phosphorus production subcategory. 422.10 Section 422.10 Protection of Environment ENVIRONMENTAL PROTECTION... Phosphorus Production Subcategory § 422.10 Applicability; description of the phosphorus production... production of phosphorus and ferrophosphorus by smelting of phosphate ore. ...

40 CFR 422.10 - Applicability; description of the phosphorus production subcategory.

Code of Federal Regulations, 2011 CFR

2011-07-01

... phosphorus production subcategory. 422.10 Section 422.10 Protection of Environment ENVIRONMENTAL PROTECTION... Phosphorus Production Subcategory § 422.10 Applicability; description of the phosphorus production... production of phosphorus and ferrophosphorus by smelting of phosphate ore. ...

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. IWA Publishing 2008.

40 CFR 721.2752 - Epoxy resin containing phosphorus (generic).

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Epoxy resin containing phosphorus... Specific Chemical Substances § 721.2752 Epoxy resin containing phosphorus (generic). (a) Chemical substance... epoxy resin containing phosphorus (PMN P-00-912) is subject to reporting under this section for the...

40 CFR 721.2752 - Epoxy resin containing phosphorus (generic).

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Epoxy resin containing phosphorus... Specific Chemical Substances § 721.2752 Epoxy resin containing phosphorus (generic). (a) Chemical substance... epoxy resin containing phosphorus (PMN P-00-912) is subject to reporting under this section for the...

40 CFR 721.2752 - Epoxy resin containing phosphorus (generic).

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Epoxy resin containing phosphorus... Specific Chemical Substances § 721.2752 Epoxy resin containing phosphorus (generic). (a) Chemical substance... epoxy resin containing phosphorus (PMN P-00-912) is subject to reporting under this section for the...

40 CFR 721.2752 - Epoxy resin containing phosphorus (generic).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Epoxy resin containing phosphorus... Specific Chemical Substances § 721.2752 Epoxy resin containing phosphorus (generic). (a) Chemical substance... epoxy resin containing phosphorus (PMN P-00-912) is subject to reporting under this section for the...

40 CFR 721.2752 - Epoxy resin containing phosphorus (generic).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Epoxy resin containing phosphorus... Specific Chemical Substances § 721.2752 Epoxy resin containing phosphorus (generic). (a) Chemical substance... epoxy resin containing phosphorus (PMN P-00-912) is subject to reporting under this section for the...

Sustainable Phosphorus Loadings from Effective and Cost-Effective Phosphorus Management Around the Baltic Sea

PubMed Central

Bryhn, Andreas C.

2009-01-01

Nutrient over-enrichment of the Baltic Sea, accompanied by intensified algal blooms and decreasing water clarity, has aroused widespread concern in the surrounding countries during the last four decades. This work has used a well-tested dynamic mass-balance model to investigate which decrease in total phosphorus loading would be required to meet the environmental goal to restore the trophic state in the Baltic Sea to pre-1960s levels. Furthermore, the extent to which various abatement options may decrease the phosphorus loading in a cost-effective manner has been studied. Upgrading urban sewage treatment in the catchment could, alone or in combination with banning phosphates in detergents, be sufficient to meet the set environmental goal, at an estimated annual basin-wide cost of 0.21–0.43 billion euro. Such a plan would potentially decrease the total phosphorus loading to the Baltic Sea with 6,650–10,200 tonnes per year. PMID:19412551

Black phosphorus saturable absorber for ultrashort pulse generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sotor, J., E-mail: jaroslaw.sotor@pwr.edu.pl; Sobon, G.; Abramski, K. M.

Low-dimensional materials, due to their unique and versatile properties, are very interesting for numerous applications in electronics and optoelectronics. Recently rediscovered black phosphorus, with a graphite-like layered structure, can be effectively exfoliated up to the single atomic layer called phosphorene. Contrary to graphene, it possesses a direct band gap controllable by the number of stacked atomic layers. For those reasons, black phosphorus is now intensively investigated and can complement or replace graphene in various photonics and electronics applications. Here, we demonstrate that black phosphorus can serve as a broadband saturable absorber and can be used for ultrashort optical pulse generation.more » The mechanically exfoliated ∼300 nm thick layers of black phosphorus were transferred onto the fiber core, and under pulsed excitation at 1560 nm wavelength, its transmission increases by 4.6%. We have demonstrated that the saturable absorption of black phosphorus is polarization sensitive. The fabricated device was used to mode-lock an Er-doped fiber laser. The generated optical solitons with the 10.2 nm bandwidth and 272 fs duration were centered at 1550 nm. The obtained results unambiguously show that black phosphorus can be effectively used for ultrashort pulse generation with performances similar or even better than currently used graphene or carbon nanotubes. This application of black phosphorus proves its great potential to future practical use in photonics.« less

Monitoring to assess progress toward meeting the total maximum daily load for phosphorus in the Assabet River, Massachusetts: phosphorus loads, 2008 through 2010

USGS Publications Warehouse

Zimmerman, Marc J.; Savoie, Jennifer G.

2013-01-01

Wastewater discharges to the Assabet River contribute substantial amounts of phosphorus, which support accumulations of nuisance aquatic plants that are most evident in the river’s impounded reaches during the growing season. To restore the Assabet River’s water quality and aesthetics, the U.S. Environmental Protection Agency required the major wastewater-treatment plants in the drainage basin to reduce the amount of phosphorus discharged to the river by 2012. From October 2008 to December 2010, the U.S. Geological Survey, in cooperation with the Massachusetts Department of Environmental Protection and in support of the requirements of the Total Maximum Daily Load for Phosphorus, collected weekly flow-proportional, composite samples for analysis of concentrations of total phosphorus and orthophosphorus upstream and downstream from each of the Assabet River’s two largest impoundments: Hudson and Ben Smith. The purpose of this monitoring effort was to evaluate conditions in the river before enhanced treatment-plant technologies had effected reductions in phosphorus loads, thereby defining baseline conditions for comparison with conditions following the mandated load reductions. The locations of sampling sites with respect to the impoundments enabled examination of the impoundments’ effects on phosphorus sequestration and on the transformation of phosphorus between particulate and dissolved forms. The study evaluated the differences between loads upstream and downstream from the impoundments throughout the sampling period and compared differences during two seasonal periods of relevance to aquatic plants: April 1 through October 31, the growing season, and November 1 through March 31, the nongrowing season, when existing permit limits allowed average monthly wastewater-treatment-plant-effluent concentrations of 0.75 milligram per liter (growing season) or 1.0 milligram per liter (nongrowing season) for total phosphorus. At the four sampling sites during the

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.

Environmental Benefits and Burdens of Phosphorus Recovery from Municipal Wastewater.

PubMed

Bradford-Hartke, Zenah; Lane, Joe; Lant, Paul; Leslie, Gregory

2015-07-21

The environmental benefits and burdens of phosphorus recovery in four centralized and two decentralized municipal wastewater systems were compared using life cycle assessment (LCA). In centralized systems, phosphorus recovered as struvite from the solids dewatering liquid resulted in an environmental benefit except for the terrestrial ecotoxicity and freshwater eutrophication impact categories, with power and chemical use offset by operational savings and avoided fertilizer production. Chemical-based phosphorus recovery, however, generally required more resources than were offset by avoided fertilizers, resulting in a net environmental burden. In decentralized systems, phosphorus recovery via urine source separation reduced the global warming and ozone depletion potentials but increased terrestrial ecotoxicity and salinization potentials due to application of untreated urine to land. Overall, mineral depletion and eutrophication are well-documented arguments for phosphorus recovery; however, phosphorus recovery does not necessarily present a net environmental benefit. While avoided fertilizer production does reduce potential impacts, phosphorus recovery does not necessarily offset the resources consumed in the process. LCA results indicate that selection of an appropriate phosphorus recovery method should consider both local conditions and other environmental impacts, including global warming, ozone depletion, toxicity, and salinization, in addition to eutrophication and mineral depletion impacts.

The Galactic evolution of phosphorus

NASA Astrophysics Data System (ADS)

Caffau, E.; Bonifacio, P.; Faraggiana, R.; Steffen, M.

2011-08-01

Context. As a galaxy evolves, its chemical composition changes and the abundance ratios of different elements are powerful probes of the underlying evolutionary processes. Phosphorous is an element whose evolution has remained quite elusive until now, because it is difficult to detect in cool stars. The infrared weak P i lines of the multiplet 1, at 1050-1082 nm, are the most reliable indicators of the presence of phosphorus. The availability of CRIRES at VLT has permitted access to this wavelength range in stellar spectra. Aims: We attempt to measure the phosphorus abundance of twenty cool stars in the Galactic disk. Methods: The spectra are analysed with one-dimensional model-atmospheres computed in local thermodynamic equilibrium (LTE). The line formation computations are performed assuming LTE. Results: The ratio of phosphorus to iron behaves similarly to sulphur, increasing towards lower metallicity stars. Its ratio with respect to sulphur is roughly constant and slightly larger than solar, [P/S] = 0.10 ± 0.10. Conclusions: We succeed in taking an important step towards the understanding of the chemical evolution of phosphorus in the Galaxy. However, the observed rise in the P/Fe abundance ratio is steeper than predicted by Galactic chemical evolution model developed by Kobayashi and collaborators. Phosphorus appears to evolve differently from the light odd-Z elements sodium and aluminium. The constant value of [P/S] with metallicity implies that P production is insensitive to the neutron excess, thus processes other than neutron captures operate. We suggest that proton captures on 30Si and α captures on 27Al are possibilities to investigate. We see no clear distinction between our results for stars with planets and stars without any detected planet. Based on observations obtained with the CRIRES spectrograph at ESO-VLT Antu 8.2 m telescope at Paranal, Programme 386.D-0130, P.I. E. Caffau.

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.

[The constribution of Justyne Siegemundin, the midwife of the Brandenburg court, to the development of the obstetrics at XVII century].

PubMed

Kraśnianin, Elzbieta; Semczuk, Andrzej

2006-12-01

From the beginning of the world assisting during childbirth was and is the women's domain. On the evolution this profession composed of many famous midwifes. Into this group unquestionably we can count Justine Siegemundin (1636-1705), midwife-self-taught person. Her activity contributed to rise the obstetrics knowledge in XVII century. Justine Siegemundin, the midwife of the Brandenburg court, published in 1690 a book describing a surgical trick still bears her name today. It is called the "double hold"--"Gedoppelter Handgriff", or "Siegemundin-Handgriff". This book counts as on the most important milestones of obstetrics history.

First-principles study of the effect of phosphorus on nickel grain boundary

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Wenguan; Ren, Cuilan; Han, Han, E-mail: hanhan@sinap.ac.cn, E-mail: xuhongjie@sinap.ac.cn

2014-01-28

Based on first-principles quantum-mechanical calculations, the impurity-dopant effects of phosphorus on Σ5(012) symmetrical tilt grain boundary in nickel have been studied. The calculated binding energy suggests that phosphorus has a strong tendency to segregate to the grain boundary. Phosphorus forms strong and covalent-like bonding with nickel, which is beneficial to the grain boundary cohesion. However, a too high phosphorus content can result in a thin and fragile zone in the grain boundary, due to the repulsion between phosphorus atoms. As the concentration of phosphorus increases, the strength of the grain boundary increases first and then decreases. Obviously, there exists anmore » optimum concentration for phosphorus segregation, which is consistent with observed segregation behaviors of phosphorus in the grain boundary of nickel. This work is very helpful to understand the comprehensive effects of phosphorus.« less

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.

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.

Long-term accumulation and transport of anthropogenic phosphorus in three river basins

NASA Astrophysics Data System (ADS)

Powers, Stephen M.; Bruulsema, Thomas W.; Burt, Tim P.; Chan, Neng Iong; Elser, James J.; Haygarth, Philip M.; Howden, Nicholas J. K.; Jarvie, Helen P.; Lyu, Yang; Peterson, Heidi M.; Sharpley, Andrew N.; Shen, Jianbo; Worrall, Fred; Zhang, Fusuo

2016-05-01

Global food production depends on phosphorus. Phosphorus is broadly applied as fertilizer, but excess phosphorus contributes to eutrophication of surface water bodies and coastal ecosystems. Here we present an analysis of phosphorus fluxes in three large river basins, including published data on fertilizer, harvested crops, sewage, food waste and river fluxes. Our analyses reveal that the magnitude of phosphorus accumulation has varied greatly over the past 30-70 years in mixed agricultural-urban landscapes of the Thames Basin, UK, the Yangtze Basin, China, and the rural Maumee Basin, USA. Fluxes of phosphorus in fertilizer, harvested crops, food waste and sewage dominate over the river fluxes. Since the late 1990s, net exports from the Thames and Maumee Basins have exceeded inputs, suggesting net mobilization of the phosphorus pool accumulated in earlier decades. In contrast, the Yangtze Basin has consistently accumulated phosphorus since 1980. Infrastructure modifications such as sewage treatment and dams may explain more recent declines in total phosphorus fluxes from the Thames and Yangtze Rivers. We conclude that human-dominated river basins may undergo a prolonged but finite accumulation phase when phosphorus inputs exceed agricultural demand, and this accumulated phosphorus may continue to mobilize long after inputs decline.

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

Environmental and resource implications of phosphorus recovery from waste activated sludge.

PubMed

Sørensen, Birgitte Lilholt; Dall, Ole Leinikka; Habib, Komal

2015-11-01

Phosphorus is an essential mineral resource for the growth of crops and thus necessary to feed the ever increasing global population. The essentiality and irreplaceability of phosphorus in food production has raised the concerns regarding the long-term phosphorus availability and the resulting food supply issues in the future. Hence, the recovery of phosphorus from waste activated sludge and other waste streams is getting huge attention as a viable solution to tackle the potential availability issues of phosphorus in the future. This study explores the environmental implications of phosphorus recovery from waste activated sludge in Denmark and further elaborates on the potential availability or scarcity issue of phosphorus today and 2050. Life cycle assessment is used to assess the possibility of phosphorus recovery with little or no environmental impacts compared to the conventional mining. The phosphorus recovery method assessed in this study consists of drying process, and thermal gasification of the waste activated sludge followed by extraction of phosphorus from the ashes. Our results indicate that the environmental impacts of phosphorus recovery in an energy efficient process are comparable to the environmental effects from the re-use of waste activated sludge applied directly on farmland. Moreover, our findings conclude that the general recommendation according to the waste hierarchy, where re-use of the waste sludge on farmland is preferable to material and energy recovery, is wrong in this case. Especially when phosphorus is a critical resource due to its life threatening necessity, lack of substitution options and potential future supply risk originating due to the high level of global supply concentration. Copyright © 2015 Elsevier Ltd. All rights reserved.

Secondary poisoning of kestrels by white phosphorus

USGS Publications Warehouse

Sparling, D.W.; Federoff, N.E.

1997-01-01

Since 1982, extensive waterfowl mortality due to white phosphorus (P4) has been observed at Eagle River Flats, a tidal marsh near Anchorage, Alaska. Ducks and swans that ingest P4 pellets become lethargic and may display severe convulsions. Intoxicated waterfowl attract raptors and gulls that feed on dead or dying birds. To determine if avian predators can be affected by secondary poisoning, we fed American kestrels (Falco sparverius) 10-day-old domestic chickens that had been dosed with white phosphorus. Eight of 15 kestrels fed intact chicks with a pellet of P4 implanted in their crops died within seven days. Three of 15 kestrels fed chicks that had their upper digestive tracts removed to eliminate any pellets of white phosphorus also died. Hematocrit and hemoglobin in kestrels decreased whereas lactate dehydrogenaseL, glucose, and alanine aminotransferase levels in plasma increased with exposure to contaminated chicks. Histological examination of liver and kidneys showed that the incidence and severity of lesions increased when kestrels were fed contaminated chicks. White phosphorus residues were measurable in 87% of the kestrels dying on study and 20% of the survivors. This study shows that raptors can become intoxicated either by ingesting portions of digestive tracts containing white phosphorus pellets or by consuming tissues of P4 contaminated prey.

The Spatial-temperal Distribution of Phosphorus Species and the Main Factors Influencing on Phosphorus Transportation in Middle Reaches of the Yarlung Zangbo River, China

NASA Astrophysics Data System (ADS)

Pu, X.; An, R.; Li, R.; Huang, W.; Li, J.

2017-12-01

The objectives of the current study are to investigate the spatial, temperal variation of phisphorus (P) fraction in middle reaches of the Yarlung Zangbo River of China. Samples were collected in April (dry season), August (wet season), and Octber (normal season) along with the middle reaches from Lazi site to Nuxia sitewhich which is about 1000km long. Sequential extraction were applied to determine the forms of phosphorus in suspended particles and to assess the potential bioavailability of particulate P. The results indicated that the distribution of suspended particle size inflenced not only the total phosphorus concentration, but also the proportions of different forms of phosphorus. The exchangeable phosphorus (Ex-P), Fe-bound-P, Ca-bound-P were the most aboundant forms and the highest proportions of total P. The total P concentrations were closely relative to the concentration of suspended particles. According to the characteristics of suspended particles in the Yarlung Zangbo River, the relationship between the suspended particles size and species of phosphorus was established though statistical analysis. The Ex-P increased with the decreasing of suspended particulate size. The content of bioavailable particulate phosphorus varied greatly with the proportions of particulate size. In genral, the higher the proportion of smaller particle size, the higher the content of bioavailable phosphorus. The main factors which affect the phosphorus transportation in Yarlung Zangbo River had also been discussed.

Plant based phosphorus recovery from wastewater via algae and macrophytes.

PubMed

Shilton, Andrew N; Powell, Nicola; Guieysse, Benoit

2012-12-01

At present, resource recovery by irrigation of wastewater to plants is usually driven by the value of the water resource rather than phosphorus recovery. Expanded irrigation for increased phosphorus recovery may be expected as the scarcity and price of phosphorus increases, but providing the necessary treatment, storage and conveyance comes at significant expense. An alternative to taking the wastewater to the plants is instead to take the plants to the wastewater. Algal ponds and macrophyte wetlands are already in widespread use for wastewater treatment and if harvested, would require less than one-tenth of the area to recover phosphorus compared to terrestrial crops/pastures. This area could be further decreased if the phosphorus content of the macrophytes and algae biomass was tripled from 1% to 3% via luxury uptake. While this and many other opportunities for plant based recovery of phosphorus exist, e.g. offshore cultivation, much of this technology development is still in its infancy. Research that enhances our understanding of how to maximise phosphorus uptake and harvest yields; and further add value to the biomass for reuse would see the recovery of phosphorus via plants become an important solution in the future. Copyright © 2012 Elsevier Ltd. All rights reserved.

The prevalence of phosphorus-containing food additives in top-selling foods in grocery stores.

PubMed

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

2013-07-01

The objective of this study was 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. 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. Presence of phosphorus-containing food additives, phosphorus content. Forty-four percent 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 and baked goods (57%), soup (54%), and yogurt (51%) categories. Phosphorus additive-containing foods averaged 67 mg phosphorus/100 g more than matched nonadditive-containing foods (P = .03). Sample meals comprised mostly of phosphorus additive-containing foods had 736 mg more phosphorus per day compared with meals consisting of only additive-free foods. Phosphorus additive-free meals cost an average of $2.00 more per day. 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. Copyright © 2013 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

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

46 CFR 151.50-50 - Elemental phosphorus in water.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 5 2011-10-01 2011-10-01 false Elemental phosphorus in water. 151.50-50 Section 151.50... phosphorus in water. (a) Tanks shall be designed and tested for a head equivalent to the design lading of phosphorus and its water blanket extended to 8 feet above the tank top. In addition, tank design calculations...

46 CFR 151.50-50 - Elemental phosphorus in water.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 5 2010-10-01 2010-10-01 false Elemental phosphorus in water. 151.50-50 Section 151.50... phosphorus in water. (a) Tanks shall be designed and tested for a head equivalent to the design lading of phosphorus and its water blanket extended to 8 feet above the tank top. In addition, tank design calculations...

46 CFR 151.50-50 - Elemental phosphorus in water.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 5 2014-10-01 2014-10-01 false Elemental phosphorus in water. 151.50-50 Section 151.50... phosphorus in water. (a) Tanks shall be designed and tested for a head equivalent to the design lading of phosphorus and its water blanket extended to 8 feet above the tank top. In addition, tank design calculations...

46 CFR 151.50-50 - Elemental phosphorus in water.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 5 2013-10-01 2013-10-01 false Elemental phosphorus in water. 151.50-50 Section 151.50... phosphorus in water. (a) Tanks shall be designed and tested for a head equivalent to the design lading of phosphorus and its water blanket extended to 8 feet above the tank top. In addition, tank design calculations...

Factors effective on peritoneal phosphorus transport and clearance in peritoneal dialysis patients
.

PubMed

Cebeci, Egemen; Gursu, Meltem; Uzun, Sami; Karadag, Serhat; Kazancioglu, Rumeyza; Ozturk, Savas

2017-02-01

Transport characteristics of phosphorus are different from other small solutes that are evaluated in routine peritoneal equilibration test (PET) in peritoneal dialysis (PD) patients. We aimed to evaluate peritoneal phosphorus clearance and permeability, and their relationship with peritoneal membrane transport type and creatinine clearance as well as factors affecting peritoneal phosphorus clearance. 70 adult patients on a PD program were included in our study. Phosphorus transport status was classified according to dialysate/plasma (D/P) phosphorus at the 4^th hour of PET as slow transporter (< 0.47), slow-average transporter (0.47 - 0.56), fast-average transporter (0.57 - 0.67), and fast transporter (> 0.67). We evaluated the relationship of peritoneal phosphorus clearance and transport type with PD regime, phosphorus level, and presence of residual renal function in addition to investigating factors that are effective on peritoneal phosphorus clearance. D/P phosphorus and peritoneal phosphorus clearance were positively correlated with D/P creatinine and peritoneal creatinine clearance, respectively. Automated PD and continuous ambulatory PD patients were similar regarding phosphorus and creatinine clearances and transport status based on D/P phosphorus. The major determinant of peritoneal phosphorus clearance was anuria status. Anuric patients had higher dialysate volume (11.6 ± 3.0 L vs. 8.4 ± 2.1 L, p < 0.001) and therefore higher peritoneal phosphorus clearance (61.7 ± 15.1 L/week/1.73 m² vs. 48.4 ± 14.0 L/week/1.73 m², p = 0.001). Hyperphosphatemia was present in 40% and 11% of anuric patients and those with residual renal function, respectively (p = 0.005). Peritoneal phosphorus transport characteristics are similar to that of creatinine. Although increased dialysis dose may increase peritoneal phosphorus clearance, it may be insufficient to prevent hyperphosphatemia in anuric patients.
.

A Hierarchical Phosphorus Nanobarbed Nanowire Hybrid: Its Structure and Electrochemical Properties.

PubMed

Zhao, Dan; Li, Beibei; Zhang, Jinying; Li, Xin; Xiao, Dingbin; Fu, Chengcheng; Zhang, Lihui; Li, Zhihui; Li, Jun; Cao, Daxian; Niu, Chunming

2017-06-14

Nanostructured phosphorus-carbon composites are promising materials for Li-ion and Na-ion battery anodes. A hierarchical phosphorus hybrid, SiC@graphene@P, has been synthesized by the chemical vapor deposition of phosphorus on the surfaces of barbed nanowires, where the barbs are vertically grown graphene nanosheets and the cores are SiC nanowires. A temperature-gradient vaporization-condensation method has been used to remove the unhybridized phosphorus particles formed by homogeneous nucleation. The vertically grown barb shaped graphene nanosheets and a high concentration of edge carbon atoms induced a fibrous red phosphorus (f-RP) growth with its {001} planes in parallel to {002} planes of nanographene sheets and led to a strong interpenetrated interface interaction between phosphorus and the surfaces of graphene nanosheets. This hybridization has been demonstrated to significantly enhance the electrochemical performances of phosphorus.

Phosphorus Equilibria Among Mafic Silicate Phases

NASA Technical Reports Server (NTRS)

Berlin, Jana; Xirouchakis, Dimitris

2002-01-01

Phosphorus incorporation in major rock-forming silicate minerals has the following implications: (1) Reactions between phosphorus-hosting major silicates and accessory phosphates, which are also major trace element carriers, may control the stability of the latter and thus may affect the amount of phosphorus and other trace elements released to the coexisting melt or fluid phase. (2) Less of a phosphate mineral is needed to account for the bulk phosphorus of planetaty mantles. (3) During partial melting of mantle mineral assemblages or equilibrium fractional crystallization of basaltic magmas, and in the absence or prior to saturation with a phosphate mineral, silicate melts may become enriched in phosphorus, especially in the geochemically important low melt fraction regime, Although the small differences in the ionic radii of IVp5+, IVSi4+, and IV Al3+ makes phosphoms incorporation into crystalline silicates perhaps unsurprising, isostructural silicate and phosphate crystalline solids do not readily form solutions, e.g., (Fe, Mg)2SiO4 vs. LiMgPO4, SiO)2 VS. AlPO4. Nonetheless, there are reports of, poorly characterized silico-phosphate phases in angrites , 2-4 wt% P2O5 in olivine and pyroxene grains in pallasites and reduced terestrial basalts which are little understood but potentially useful, and up to 17 wt% P2O5 in olivine from ancient slags. However, such enrichments are rare and only underscore the likelihood of phosphoms incorporation in silicate minerals. The mechanisms that allow phosphorus to enter major rock-forming silicate minerals (e.g., Oliv, Px, Gt) remain little understood and the relevant data base is limited. Nonetheless, old and new high-pressure (5-10 GPa) experimental data suggest that P2O5 wt% decreases from silica-poor to silica-rich compositions or from orthosilicate to chain silicate structures (garnet > olivine > orthopyroxene) which implies that phosphorus incorporation in silicates is perhaps more structure-than site-specific. The

The comparison of phosphorus-nitrogen and sulfur-phosphorus-nitrogen on the anti-flammability and thermal degradation of cotton fabrics

USDA-ARS?s Scientific Manuscript database

The phosphorus-nitrogen (P-N) or sulfur (S) containing compounds are well known for their effectiveness as flame retardant additives for many polymeric systems. When either phosphorus or nitrogen is combined with sulfur, the new systems prove to be successful combinations. This research aims to le...

Patient-Reported Factors Associated With Poor Phosphorus Control in a Maintenance Hemodialysis Population.

PubMed

Joson, Cherriday G; Henry, Shayna L; Kim, Sue; Cheung, Mandy Y; Parab, Prajakta; Abcar, Antoine C; Jacobsen, Steven J; Morisky, Donald E; Sim, John J

2016-05-01

The purpose of this study was to determine the influence of patient-reported medication adherence and phosphorus-related knowledge on phosphorus control and pharmacy-reported adherence to phosphorus binding medication among patients on maintenance hemodialysis. Retrospective, cross-sectional cohort study. Seventy-nine hemodialysis patients (mean age 64.2 years, SD = 14 years; 46.8% female) in a stand-alone hemodialysis unit within an integrated learning healthcare system. Ten percent (10%) of subjects were Caucasian, 42% Latino, 19% African American, and 29% Asian. Forty-eight percent had diabetes; 72% had BMI ≥ 30. Inclusion criteria included the provision of survey data and having medication refill data available in the pharmacy system. 77.2% had mean phosphorus levels ≤ 5.5 mg/dL; 22.8% had mean phosphorus levels > 5.5 mg/dL. Subjects were administered the 8-item Morisky Medication Adherence Scale (MMAS-8) and also reported on their phosphorus-related knowledge. Phosphorus levels within an adequate range. The mean serum phosphorus level was 4.96 mg/dL (SD = 1.21). In the well-controlled group, mean phosphorus was 4.44 mg/dL (SD = 0.76). In the poorly controlled group, mean phosphorus was 6.69 mg/dL (SD = 0.74). A total of 61% of patients reported at least some unintentional medication nonadherence, and 48% reported intentional medication nonadherence. Phosphorus-specific knowledge was low, with just under half of patients reporting that they could not name two high-phosphorus foods or identify a phosphorus-related health risk. Phosphorus binder-related nonadherence was substantially higher in the uncontrolled than the controlled group. Adjusting for age, individuals with poorer self-reported binder adherence were less likely to have controlled phosphorus levels (odds ratio = 0.71, P = .06). Phosphorus-related non-adherence, but not low phosphorus-specific knowledge, was associated with poorer phosphorus control. Such findings provide important information

Phosphorus dendrimers and photodynamic therapy. Spectroscopic studies on two dendrimer-photosensitizer complexes: Cationic phosphorus dendrimer with rose bengal and anionic phosphorus dendrimer with methylene blue.

PubMed

Dabrzalska, Monika; Zablocka, Maria; Mignani, Serge; Majoral, Jean Pierre; Klajnert-Maculewicz, Barbara

2015-08-15

Dendrimers due to their unique architecture may play an important role in drug delivery systems including chemotherapy, gene therapy and recently, photodynamic therapy as well. We investigated two dendrimer-photosensitizer systems in context of potential use of these systems in photodynamic therapy. The mixtures of an anionic phosphorus dendrimer of the second generation and methylene blue were studied by UV-vis spectroscopy while that of a cationic phosphorus dendrimer (third generation) and rose bengal were investigated by spectrofluorimetric methods. Spectroscopic analysis of these two systems revealed the formation of dendrimer-photosensitizer complexes via electrostatic interactions as well as π stacking. The stoichiometry of the rose bengal-cationic dendrimer complex was estimated to be 7:1 and 9:1 for the methylene blue-anionic dendrimer complex. The results suggest that these polyanionic or polycationic phosphorus dendrimers can be promising candidates as carriers in photodynamic therapy. Copyright © 2015 Elsevier B.V. All rights reserved.

Phosphorus out-diffusion in laser molten silicon

DOE Office of Scientific and Technical Information (OSTI.GOV)

Köhler, J. R.; Eisele, S. J.

2015-04-14

Laser doping via liquid phase diffusion enables the formation of defect free pn junctions and a tailoring of diffusion profiles by varying the laser pulse energy density and the overlap of laser pulses. We irradiate phosphorus diffused 100 oriented p-type float zone silicon wafers with a 5 μm wide line focused 6.5 ns pulsed frequency doubled Nd:YVO{sub 4} laser beam, using a pulse to pulse overlap of 40%. By varying the number of laser scans N{sub s} = 1, 2, 5, 10, 20, 40 at constant pulse energy density H = 1.3 J/cm{sup 2} and H = 0.79 J/cm{sup 2} we examine the out-diffusion of phosphorus atoms performing secondary ionmore » mass spectroscopy concentration measurements. Phosphorus doping profiles are calculated by using a numerical simulation tool. The tool models laser induced melting and re-solidification of silicon as well as the out-diffusion of phosphorus atoms in liquid silicon during laser irradiation. We investigate the observed out-diffusion process by comparing simulations with experimental concentration measurements. The result is a pulse energy density independent phosphorus out-diffusion velocity v{sub out} = 9 ± 1 cm/s in liquid silicon, a partition coefficient of phosphorus 1 < k{sub p} < 1.1 and a diffusion coefficient D = 1.4(±0.2)cm{sup 2}/s × 10{sup −3 }× exp[−183 meV/(k{sub B}T)].« less

Vertical distribution of sediment phosphorus in Lake Hachirogata related to the effect of land reclamation on phosphorus accumulation.

PubMed

Jin, G; Onodera, S; Saito, M; Maruyama, Y; Hayakawa, A; Sato, T; Ota, Y; Aritomi, D

2016-01-13

The focus of this work is the change in sediment properties and chemical characteristics that occur after land reclamation projects. The results indicate a higher sedimentation rate in Lake Hachirogata after reclamation, with the rate increasing with proximity to the agricultural zone. In the west-side water samples, higher levels of dissolved total nitrogen and dissolved total phosphorus (DTP) were found in both surface and bottom waters. The increase in P (39-80%) was generally greater than that for N (12-16%), regarding the nutrient supply from reclaimed farmland in the western part of the lake. In the eastern part of the lake, the pore-water Cl - profile showed a decreasing vertical gradient in the sediment core. This indicates desalination of the lake water after construction of a sluice gate in 1961. In the western sediment-core sample, a uniform Cl - profile indicates the mixing of lake water and pore water after reclamation. Considering the sedimentation of P in the last 100 years, there is a trend of increasing accumulation of P and P-activities after the reclamation project. This appears to be an impact from change in the lake environment as a result of increased agricultural nutrients, desalination, and residence. A large amount of mobile phosphorus (42-72% of TP in the western core sample) trapped in sediment increases the risk of phosphorus release and intensification of algal blooms. High sediment phosphorus and phosphorus mobility should be considered a source of pollution in the coastal environment.

Phosphorus Utilization and Characterization of Excreta From Swine Fed Diets Containing A Variety of Cereal Grains Balanced For Total Phosphorus

USDA-ARS?s Scientific Manuscript database

Intrinsic phytase in swine feeds may alter phytate utilization and solubility of excreted phosphorus. Therefore, the objective of this experiment was to quantify changes in fecal phosphorus composition from swine fed various cereal grains with a range of phytate concentrations and endogenous phytase...

Monitoring to assess progress toward meeting the Assabet River, Massachusetts, phosphorus total maximum daily load - Aquatic macrophyte biomass and sediment-phosphorus flux

USGS Publications Warehouse

Zimmerman, Marc J.; Qian, Yu; Yong Q., Tian

2011-01-01

In 2004, the Total Maximum Daily Load (TMDL) for Total Phosphorus in the Assabet River, Massachusetts, was approved by the U.S. Environmental Protection Agency. The goal of the TMDL was to decrease the concentrations of the nutrient phosphorus to mitigate some of the instream ecological effects of eutrophication on the river; these effects were, for the most part, direct consequences of the excessive growth of aquatic macrophytes. The primary instrument effecting lower concentrations of phosphorus was to be strict control of phosphorus releases from four major wastewatertreatment plants in Westborough, Marlborough, Hudson, and Maynard, Massachusetts. The improvements to be achieved from implementing this control were lower concentrations of total and dissolved phosphorus in the river, a 50-percent reduction in aquatic-plant biomass, a 30-percent reduction in episodes of dissolved oxygen supersaturation, no low-flow dissolved oxygen concentrations less than 5.0 milligrams per liter, and a 90-percent reduction in sediment releases of phosphorus to the overlying water. In 2007, the U.S. Geological Survey, in cooperation with the Massachusetts Department of Environmental Protection, initiated studies to evaluate conditions in the Assabet River prior to the upgrading of wastewater-treatment plants to remove more phosphorus from their effluents. The studies, completed in 2008, implemented a visual monitoring plan to evaluate the extent and biomass of the floating macrophyte Lemna minor (commonly known as lesser duckweed) in five impoundments and evaluated the potential for phosphorus flux from sediments in impounded and free-flowing reaches of the river. Hydrologically, the two study years 2007 and 2008 were quite different. In 2007, summer streamflows, although low, were higher than average, and in 2008, the flows were generally higher than in 2007. Visually, the effects of these streamflow differences on the distribution of Lemna were obvious. In 2007, large amounts of

Sodium adsorption and diffusion on monolayer black phosphorus with intrinsic defects

NASA Astrophysics Data System (ADS)

Sun, Xiaoli; Wang, Zhiguo

2018-01-01

Monolayer black phosphorus is a potential anode material for rechargeable ion batteries. In this work, the effects of intrinsic defects including mono-vacancy (MV), di-vacancy, and Stone-Wales (SW) defects on the adsorption and diffusion of sodium on monolayer black phosphorus were investigated using first-principles calculations. The adsorption energies for sodium on monolayer black phosphorus are in the range of -1.80 to -0.56 eV, which is lower than the value of -0.48 eV for sodium adsorbed on pristine monolayer phosphorus. This indicates that these defects can enhance the adsorption of sodium on monolayer black phosphorus. The diffusivity of sodium on monolayer phosphorus with SW and MV defects is 2.35 × 10-4-3.36 × 10-6 cm2/s, and 7.38 × 10-5-1.48 × 10-9 cm2/s, respectively. Although these values are smaller than that of the pristine monolayer phosphorus at 7.38 × 10-5 cm2/s, defects are inevitably introduced during these fabrication processes. These diffusivity values are reasonable for defective monolayer phosphorus used as an effective anode for sodium ion batteries.

Interspecific variability in phosphorus-induced lipid remodelling among marine eukaryotic phytoplankton.

PubMed

Cañavate, José Pedro; Armada, Isabel; Hachero-Cruzado, Ismael

2017-01-01

The response of marine microalgal lipids to phosphorus is of central importance in phytoplankton ecology but remains poorly understood. We determined how taxonomically diverse microalgal species remodelled their lipid class profile in response to phosphorus availability and whether these changes coincided with those already known to occur in land plants and in the limited number of phytoplankton species for which data are available. The complete lipid class profile and specific lipid ratios influenced by phosphorus availability were quantified in two green microalgae and seven Chromalveolates exposed to phosphorus repletion, deprivation and replenishment. Lipid class cell quota changes in the two green microalgae resembled the currently described pattern of betaine lipids substituting for phospholipids under phosphorus depletion, whereas only two of the studied Chromalveolates showed this pattern. Sulpholipids counterbalanced phosphatidylglycerol only in Picochlorum atomus. In all other species, both lipids decreased simultaneously under phosphorus deprivation, although sulpholipids declined more slowly. Phosphorus deprivation always induced a decrease in digalactosyl-diacylglycerol. However, the ratio of digalactosyl-diacylglycerol to total phospholipids increased in eight species and remained unchanged in Isochrysis galbana. Marine phytoplankton seems to have evolved a diversified mechanism for remodelling its lipid class profile under the influence of phosphorus, with cryptophytes and particularly haptophytes exhibiting previously unobserved lipid responses to phosphorus. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Anaerobic fermentation combined with low-temperature thermal pretreatment for phosphorus-accumulating granular sludge: Release of carbon source and phosphorus as well as hydrogen production potential.

PubMed

Zou, Jinte; Li, Yongmei

2016-10-01

Releases of organic compounds and phosphorus from phosphorus-accumulating granular sludge (PGS) and phosphorus-accumulating flocculent sludge (PFS) during low-temperature thermal pretreatment and anaerobic fermentation were investigated. Meanwhile, biogas production potential and microbial community structures were explored. The results indicate that much more soluble chemical oxygen demand (SCOD) and phosphorus were released from PGS than from PFS via low-temperature thermal pretreatment because of the higher extracellular polymeric substances (EPS) content in PGS and higher ratio of phosphorus reserved in EPS. Furthermore, PGS contains more anaerobes and dead cells, resulting in much higher SCOD and volatile fatty acids release from PGS than those from PFS during fermentation. PGS fermentation facilitated the n-butyric acid production, and PGS exhibited the hydrogen production potential during fermentation due to the presence of hydrogen-producing bacteria. Therefore, anaerobic fermentation combined with low-temperature thermal pretreatment can facilitate the recovery of carbon and phosphorus as well as producing hydrogen from PGS. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of dietary phosphorus on the growth and body components of juvenile Synechogobius hasta

NASA Astrophysics Data System (ADS)

Luo, Zhi; Li, Xiaodong; Gong, Shiyuan; Xi, Wenqiu; Li, Yali

2009-03-01

The effect of dietary phosphorus on the growth and body components of juvenile Synechogobius hasta was determined. Different percentages of dietary phosphorus (0.63, 0.77, 0.93, 1.06, 1.22 and 1.36) were tested by feeding the fish (body weight, 15.81 g ± 0.32 g; 20 individuals each group; 3 groups each percentage) at a surplus of 5%-10% above satiation for 35 d. Dietary phosphorus did not significantly affect the specific growth rate, feed intake, feed conversion ratio and protein efficiency rate. Nitrogen retention was found to be the highest in fish fed the diet containing 1.06% of phosphorus; however, this was not significantly different from other diets. Fish fed the diet containing 0.93% of phosphorus showed the highest phosphorus retention; similar phosphorus retention rates were found in fish fed the diets containing 0.77% and 1.06% of phosphorus. Fish fed the diet containing the highest percentage of dietary phosphorus were found to contain the least whole body lipid, lower than fish fed other diets ( P<0.05). The protein content increased from 18.59% to 19.55% (although not significant) with the decrease of body lipid content ( P>0.05). The contents of the whole body ash, whole body phosphorus and vertebrae phosphorus increased with dietary phosphorus percentage up to 1.06 ( P<0.05), reaching a plateau after that. Dietary phosphorus did not significantly influence the muscle components (protein, lipid and moisture). Condition factor and hepatosomatic index were the highest in fish fed the diet containing 0.63% of dietary phosphorus; however, this was not significantly different from those of other diets. The second-order polynomial regression of phosphorus retention against dietary phosphorus identified a breakpoint at 0.88% of dietary phosphorus. However, the dietary requirement of phosphorus for maintaining maximum phosphorus storage determined by broken-line analysis of the contents of whole body phosphorus, and ash and vertebrae phosphorus was 1

Phosphorus Balance in Adolescent Girls and the Effect of Supplemental Dietary Calcium.

PubMed

Vorland, Colby J; Martin, Berdine R; Weaver, Connie M; Peacock, Munro; Gallant, Kathleen M Hill

2018-03-01

There are limited data on phosphorus balance and the effect of dietary calcium supplements on phosphorus balance in adolescents. The purpose of this study was to determine phosphorus balance and the effect of increasing dietary calcium intake with a supplement on net phosphorus absorption and balance in healthy adolescent girls. This study utilized stored urine, fecal, and diet samples from a previously conducted study that focused on calcium balance. Eleven healthy girls ages 11 to 14 years participated in a randomized crossover study, which consisted of two 3-week periods of a controlled diet with low (817 ± 19.5 mg/d) or high (1418 ± 11.1 mg/d) calcium, separated by a 1-week washout period. Phosphorus intake was controlled at the same level during both placebo and calcium supplementation (1435 ± 23.5 and 1453 ± 28.0 mg/d, respectively, p = 0.611). Mean phosphorus balance was positive by about 200 mg/d and was unaffected by the calcium supplement ( p = 0.826). Urinary phosphorus excretion was lower with the calcium supplement (535 ± 42 versus 649 ± 41 mg/d, p = 0.013), but fecal phosphorus and net phosphorus absorption were not significantly different between placebo and calcium supplement (553 ± 60 versus 678 ± 63 versus mg/d, p = 0.143; 876 ± 62 versus 774 ± 64 mg/d, p = 0.231, respectively). Dietary phosphorus underestimates using a nutrient database compared with the content measured chemically from meal composites by ~40%. These results show that phosphorus balance is positive in girls during adolescent growth and that a calcium dietary supplement to near the current recommended level does not affect phosphorus balance when phosphorus intake is at 1400 mg/d, a typical US intake level. © 2017 American Society for Bone and Mineral Research.

Global baseline data on phosphorus pollution of large lakes

NASA Astrophysics Data System (ADS)

Fink, Gabriel; Flörke, Martina; Alcamo, Joseph

2016-04-01

Lakes are exposed to harmful eutrophication which is the most concerning water quality issue on global scale. Eutrophication is caused by phosphorous pollution in most lakes. Hence, global consistent base line data on phosphorus loadings are needed to assess future sustainable development. We used the modeling framework WaterGAP3 to calculate present total phosphorus loadings to the world's largest lakes. Estimates of modeled total phosphorus (TP) loadings as well as the contributions of different sectors were successfully validated against measured data. Based on these findings, annual total phosphorus loadings to lakes were calculated for diffuse and point sources according to the different sectors domestic, manufacturing, urban surface runoff, agriculture and background for the time period 1990 to 2010. Our results show high phosphorus loadings into lakes in southern latitudes. On global average, industrial fertilizer is the main anthropogenic source while background loadings are low in comparison. Nevertheless, both features indicate a high potential to reduce the exposure to eutrophication in lakes which are faced with high phosphor inputs. The global average of TP loadings was 7% higher in the time period 2005-2010 than in the period 1990-1995. The global average in 2005-2010 results from an increase in TP loadings of 79% in South America, which was dampened by a decrease in Europe, North America, and Asia. Chinese lakes were exposed to massive increasing phosphorus loadings, too. Both increasing and decreasing trends are caused primarily by changing industrial fertilizer application rates. In conclusion, this study provides a consistent and model based synopsis of global trends and sources of phosphorus loadings to large lakes. The estimates of phosphorus pollution of lakes present a basis for assessing and managing the global eutrophication problem.

Reversible changes of the muscle cell in experimental phosphorus deficiency.

PubMed Central

Fuller, T J; Carter, N W; Barcenas, C; Knochel, J P

1976-01-01

Both animal and human studies suggest that either phosphorus depletion or hypophosphatemia might have an adverse effect on muscle function and composition. Recently a possible deleterious effect was noted in patients with chronic alcoholism. In this unexplained disease, a variety of toxic and nutritional disturbances could affect the muscle cell, thus obscuring the precise role of phosphorus. Accordingly, we examined eight conditioned dogs for the possibility that phosphorus deficiency per se might induce an abnormally low resting transmembrane electrical potential difference (Em) and alter the composition of the muscle cell. Eight conditioned dogs were fed a synthetic phosphorus-deficient but otherwise nutritionally adequate diet plus aluminum carbonate gel for a 28-day period followed by the same diet with phosphorus supplementation for an additional 28 days. Sequential measurements of Em and muscle composition were made at 0 and 28 days during depletion and again after phosphorus repletion. Serum inorganic phosphorus concentration (mg/100 ml) fell from 4.2 +/- 0.6 on day 0 t0 1.7 +/- 0.1 on day 28. Total muscle phosphorus content (mmol/100 g fat-free dry wt [FFDW]) fell from 28.5 +/- 1.8 on day 0 to 22.4 +/- 2.1 on day 28. During phosphorus depletion, average Em (-mV) fell from 92.6 +/- 4.2 to 77.9 +/- 4.1 mV (P less than 0.001). Muscle Na+ and Cl- content (meq/100 g FFDW) rose respectively from 11.8 +/- 3.2 to 17.2 +/- 2.8 (P less than 0.01) and from 8.4 +/- 1.4 to 12.7 +/- 2.0 (P less than 0.001). Total muscle water content rose from 331 +/- 12 to 353 +/- 20 g/100 FFDW (P less than 0.05). A slight, but nevertheless, significant drop in muscle potassium content, 43.7 +/- 2.0-39.7 +/- 2.2 meq/100 g FFDW (P less than 0.05) was also noted. After 4 wk of phosphorus repletion, all of these measurements returned toward control values. We conclude that moderate phosphorus depletion can induce reversible changes in skeletal muscle composition and transmembrane

A representation of the phosphorus cycle for ORCHIDEE (revision 4520)

NASA Astrophysics Data System (ADS)

Goll, Daniel S.; Vuichard, Nicolas; Maignan, Fabienne; Jornet-Puig, Albert; Sardans, Jordi; Violette, Aurelie; Peng, Shushi; Sun, Yan; Kvakic, Marko; Guimberteau, Matthieu; Guenet, Bertrand; Zaehle, Soenke; Penuelas, Josep; Janssens, Ivan; Ciais, Philippe

2017-10-01

Land surface models rarely incorporate the terrestrial phosphorus cycle and its interactions with the carbon cycle, despite the extensive scientific debate about the importance of nitrogen and phosphorus supply for future land carbon uptake. We describe a representation of the terrestrial phosphorus cycle for the ORCHIDEE land surface model, and evaluate it with data from nutrient manipulation experiments along a soil formation chronosequence in Hawaii. ORCHIDEE accounts for the influence of the nutritional state of vegetation on tissue nutrient concentrations, photosynthesis, plant growth, biomass allocation, biochemical (phosphatase-mediated) mineralization, and biological nitrogen fixation. Changes in the nutrient content (quality) of litter affect the carbon use efficiency of decomposition and in return the nutrient availability to vegetation. The model explicitly accounts for root zone depletion of phosphorus as a function of root phosphorus uptake and phosphorus transport from the soil to the root surface. The model captures the observed differences in the foliage stoichiometry of vegetation between an early (300-year) and a late (4.1 Myr) stage of soil development. The contrasting sensitivities of net primary productivity to the addition of either nitrogen, phosphorus, or both among sites are in general reproduced by the model. As observed, the model simulates a preferential stimulation of leaf level productivity when nitrogen stress is alleviated, while leaf level productivity and leaf area index are stimulated equally when phosphorus stress is alleviated. The nutrient use efficiencies in the model are lower than observed primarily due to biases in the nutrient content and turnover of woody biomass. We conclude that ORCHIDEE is able to reproduce the shift from nitrogen to phosphorus limited net primary productivity along the soil development chronosequence, as well as the contrasting responses of net primary productivity to nutrient addition.

Impact of Phosphorus-Based Food Additives on Bone and Mineral Metabolism.

PubMed

Gutiérrez, Orlando M; Luzuriaga-McPherson, Alexandra; Lin, Yiming; Gilbert, Linda C; Ha, Shin-Woo; Beck, George R

2015-11-01

Phosphorus-based food additives can substantially increase total phosphorus intake per day, but the effect of these additives on endocrine factors regulating bone and mineral metabolism is unclear. This study aimed to examine the effect of phosphorus additives on markers of bone and mineral metabolism. Design and Setting, and Participants: This was a feeding study of 10 healthy individuals fed a diet providing ∼1000 mg of phosphorus/d using foods known to be free of phosphorus additives for 1 week (low-additive diet), immediately followed by a diet containing identical food items; however, the foods contained phosphorus additives (additive-enhanced diet). Parallel studies were conducted in animals fed low- (0.2%) and high- (1.8%) phosphorus diets for 5 or 15 weeks. The changes in markers of mineral metabolism after each diet period were measured. Participants were 32 ± 8 years old, 30% male, and 70% black. The measured phosphorus content of the additive-enhanced diet was 606 ± 125 mg higher than the low-additive diet (P < .001). After 1 week of the low-additive diet, consuming the additive-enhanced diet for 1 week significantly increased circulating fibroblast growth factor 23 (FGF23), osteopontin, and osteocalcin concentrations by 23, 10, and 11%, respectively, and decreased mean sclerostin concentrations (P < .05 for all). Similarly, high-phosphorus diets in mice significantly increased blood FGF23, osteopontin and osteocalcin, lowered sclerostin, and decreased bone mineral density (P < .05 for all). The enhanced phosphorus content of processed foods can disturb bone and mineral metabolism in humans. The results of the animal studies suggest that this may compromise bone health.

Phosphorus Segregation in Meta-Rapidly Solidified Carbon Steels

NASA Astrophysics Data System (ADS)

Li, Na; Qiao, Jun; Zhang, Junwei; Sha, Minghong; Li, Shengli

2017-09-01

Twin-roll strip casters for near-net-shape manufacture of steels have received increased attention in the steel industry. Although negative segregation of phosphorus occurred in twin-roll strip casting (TRSC) steels in our prior work, its mechanism is still unclear. In this work, V-shaped molds were designed and used to simulate a meta-rapid solidification process without roll separating force during twin roll casting of carbon steels. Experimental results show that no obvious phosphorus segregation exist in the V-shaped mold casting (VMC) steels. By comparing TRSC and the VMC, it is proposed that the negative phosphorus segregation during TRSC results from phosphorus redistribution driven by recirculating and vortex flow in the molten pool. Meanwhile, solute atoms near the advancing interface are overtaken and incorporated into the solid because of the high solidification speed. The high rolling force could promote the negative segregation of alloying elements in TRSC.

Phosphorus loading to McGrath and Ellis ponds, Kennebec County, Maine

USGS Publications Warehouse

Nichols, Wallace J.; Sowles, J.W.; Lobao, J.J.

1984-01-01

McGrath and Ellis Ponds in south-central Maine have been identified as having nuisance algae blooms. In 1978, a cooperative study between the U.S. Geological Survey and the Maine Department Environmental Protection was begun to evaluate areas in which restoration effort would best improve water quality of the ponds. Streamflow and phosphorus data were collected from 28 tributaries to the ponds, April 1 through September 30, 1978 and 1979. Phosphorus yields from each tributary watershed were compared to determine their relative importance to the phosphorus budgets of the ponds. Three tributaries to the ponds were estimated to contribute 44 percent of the phosphorus load, yet drain only 22 percent of the watershed. Phosphorus input to the ponds likely would be most easily reduced by instituting phosphorus control practices in parts of the basin drained by the three tributaries. (USGS)

Phosphorus recovery from municipal and fertilizer wastewater: China's potential and perspective.

PubMed

Zhou, Kuangxin; Barjenbruch, Matthias; Kabbe, Christian; Inial, Goulven; Remy, Christian

2017-02-01

Phosphorus (P) is a limited resource, which can neither be synthesized nor substituted in its essential functions as nutrient. Currently explored and economically feasible global reserves may be depleted within generations. China is the largest phosphate fertilizer producing and consuming country in the world. China's municipal wastewater contains up to 293,163Mgyear of phosphorus, which equals approximately 5.5% of the chemical fertilizer phosphorus consumed in China. Phosphorus in wastewater can be seen not only as a source of pollution to be reduced, but also as a limited resource to be recovered. Based upon existing phosphorus-recovery technologies and the current wastewater infrastructure in China, three options for phosphorus recovery from sewage sludge, sludge ash and the fertilizer industry were analyzed according to the specific conditions in China. Copyright © 2016. Published by Elsevier B.V.

Linking soil phosphorus to dissolved phosphorus losses in the midwest

USDA-ARS?s Scientific Manuscript database

Harmful and nuisance algal blooms resulting from excess phosphorus (P) have placed agriculture in the spotlight of the water quality debate. Sixty-eight site years of P loading data from 36 fields in Ohio were used to see if a soil test P (STP) concentration could be identified that would permit P a...

Phosphorus ionization in silicon doped by self-assembled macromolecular monolayers

NASA Astrophysics Data System (ADS)

Wu, Haigang; Li, Ke; Gao, Xuejiao; Dan, Yaping

2017-10-01

Individual dopant atoms can be potentially controlled at large scale by the self-assembly of macromolecular dopant carriers. However, low concentration phosphorus dopants often suffer from a low ionization rate due to defects and impurities introduced by the carrier molecules. In this work, we demonstrated a nitrogen-free macromolecule doping technique and investigated the phosphorus ionization process by low temperature Hall effect measurements. It was found that the phosphorus dopants diffused into the silicon bulk are in nearly full ionization. However, the electrons ionized from the phosphorus dopants are mostly trapped by deep level defects that are likely carbon interstitials.

Phosphorus geochemistry of recent sediments in the South Basin of Lake Winnipeg

USGS Publications Warehouse

Mayer, T.; Simpson, S.L.; Thorleifson, L.H.; Lockhart, W.L.; Wilkinson, Philip M.

2006-01-01

Lake Winnipeg supports the largest commercial fishery on Canadian Prairies. It has been influenced by a variety of environmental forces and anthropogenic activities. To gain a better understanding of recent changes in nutrient status of the lake, it is important to reconstruct its previous history from sedimentary records. Lacustrine sediments are known to be an important sink of many dissolved and suspended substances, including phosphorus, hence, they provide a permanent historical record of changes occurring in the lake. These changes may be induced by natural factors or by anthropogenic activities in the watershed. Phosphorus profiles from dated sediment cores collected in 1999 and 1994 from the South Basin of Lake Winnipeg were investigated to determine phosphorus enrichment in recent sediments. To interpret the nutrient status and depositional conditions responsible for the trends in total phosphorus, three operationally defined forms of phosphorus (P) were determined: non-apatite inorganic P, apatite P, and organic P. Significant increases in sediment phosphorus concentrations were observed in the uppermost 20 cm of the cores and several anomalies were observed at depth. A doubling in total phosphorus relative to aluminum over the last fifty years is largely due to increases in the non-apatite inorganic fraction, suggesting that much of sedimentary phosphorus increase is attributable to changes in the nutrient status of the water column related to anthropogenic inputs. Organic phosphorus exhibits a subtle increase in the upper 20 cm of the gravity cores, likely due to increases in the primary productivity of the lake. Except for the slight increase in deeper sediments, apatite phosphorus, which is thought to be of detrital origin, remained fairly constant over the length of the cores. Anomalous spikes in phosphorus concentrations deeper in the cores, comprised mainly of the non-apatite inorganic phosphorus fraction, likely resulted from natural variation in

Potential role of ammoniagenesis in the hypocalciuric effect of phosphorus in rats.

PubMed

Cerklewski, F L

1995-02-01

Hypocalciuria associated with a high phosphorus intake is known to be both a parathyroid hormone and non-parathyroid hormone dependent event. The present study was designed to define the role that ammoniagenesis may play in the non-parathyroid hormone dependent pathway. Male rats, initially weighing 160 g, were fed a purified diet containing, in g/kg diet, a single level of protein (200) and variable inorganic phosphorus (1.8, 4.5, 9.0) for 20 days. Food intake and body weight were similar for the three groups. Significant inverse correlations were found for both urinary calcium and phosphorus and for urinary ammonia nitrogen and calcium excretion (r = -0.62, p < 0.01). Urinary ammonia nitrogen excretion was highly correlated with both phosphorus intake (r = 0.89, p < 0.001) and urinary phosphorus (r = 0.88, p < 0.001). Urinary urea nitrogen tended to vary inversely with phosphorus intake. High dietary phosphorus decreased the activity of glutamine synthetase and increased the activity of glutaminase I in kidney. Tying-up some of the hydrogen ions destined for excretion by phosphorus-stimulated ammoniagenesis could reduce the interfering effect of hydrogen ion on kidney calcium reabsorption and provide a mechanism to explain why phosphorus can have a direct positive impact upon tubular calcium reabsorption.

Seagrass-Mediated Phosphorus and Iron Solubilization in Tropical Sediments

PubMed Central

2017-01-01

Tropical seagrasses are nutrient-limited owing to the strong phosphorus fixation capacity of carbonate-rich sediments, yet they form densely vegetated, multispecies meadows in oligotrophic tropical waters. Using a novel combination of high-resolution, two-dimensional chemical imaging of O2, pH, iron, sulfide, calcium, and phosphorus, we found that tropical seagrasses are able to mobilize the essential nutrients iron and phosphorus in their rhizosphere via multiple biogeochemical pathways. We show that tropical seagrasses mobilize phosphorus and iron within their rhizosphere via plant-induced local acidification, leading to dissolution of carbonates and release of phosphate, and via local stimulation of microbial sulfide production, causing reduction of insoluble Fe(III) oxyhydroxides to dissolved Fe(II) with concomitant phosphate release into the rhizosphere porewater. These nutrient mobilization mechanisms have a direct link to seagrass-derived radial O2 loss and secretion of dissolved organic carbon from the below-ground tissue into the rhizosphere. Our demonstration of seagrass-derived rhizospheric phosphorus and iron mobilization explains why seagrasses are widely distributed in oligotrophic tropical waters. PMID:29149570

Electron Doping of Ultrathin Black Phosphorus with Cu Adatoms.

PubMed

Koenig, Steven P; Doganov, Rostislav A; Seixas, Leandro; Carvalho, Alexandra; Tan, Jun You; Watanabe, Kenji; Taniguchi, Takashi; Yakovlev, Nikolai; Castro Neto, Antonio H; Özyilmaz, Barbaros

2016-04-13

Few-layer black phosphorus is a monatomic two-dimensional crystal with a direct band gap that has high carrier mobility for both holes and electrons. Similarly to other layered atomic crystals, like graphene or layered transition metal dichalcogenides, the transport behavior of few-layer black phosphorus is sensitive to surface impurities, adsorbates, and adatoms. Here we study the effect of Cu adatoms onto few-layer black phosphorus by characterizing few-layer black phosphorus field effect devices and by performing first-principles calculations. We find that the addition of Cu adatoms can be used to controllably n-dope few layer black phosphorus, thereby lowering the threshold voltage for n-type conduction without degrading the transport properties. We demonstrate a scalable 2D material-based complementary inverter which utilizes a boron nitride gate dielectric, a graphite gate, and a single bP crystal for both the p- and n-channels. The inverter operates at matched input and output voltages, exhibits a gain of 46, and does not require different contact metals or local electrostatic gating.

Phosphorus-defect interactions during thermal annealing of ion implanted silicon

NASA Astrophysics Data System (ADS)

Keys, Patrick Henry

Ion implantation of dopant atoms into silicon generates nonequilibrium levels of crystal defects that can lead to the detrimental effects of transient enhanced diffusion (TED), incomplete dopant activation, and p-n junction leakage. In order to control these effects, it is vital to have a clear understanding of dopant-defect interactions and develop models that account for these interactions. This research focuses on experimentally investigating and modeling the clustering of phosphorus dopant atoms with silicon interstitials. Damage recovery of 40keV Si+ implants in phosphorus doped wells is experimentally analyzed. The effects of background phosphorus concentration, self implant dose, and anneal temperature are investigated. Phosphorus concentrations ranging from 2.0 x 1017 to 4.0 x 1019 cm-3 and Si+ doses ranging from 5.0 x 1013 cm-2 to 2.0 x 1014 cm-2 are studied during 650-800°C anneals. A dramatic reduction in the number of interstitials bound in {311} defects with increasing phosphorus background concentration is observed. It is suggested that the reduction of interstitials in {311} defects at high phosphorus concentrations is due to the formation of phosphorus-interstitial clusters (PICs). The critical concentration for clustering (approximately 1.0 x 1019 cm-3 at 750°C) is strongly temperature dependent and in close agreement with the kink concentration of phosphorus diffusion. Information gained from these "well experiments" is applied to the study of direct phosphorus implantation. An experimental study is conducted on 40keV phosphorus implanted to a dose of 1.0 x 1014 cm-2 during 650-800°C anneals. Electrically inactive PICs are shown to form at concentrations below the solid solubility limit due to high interstitial supersaturations. Data useful for developing a model to accurately predict phosphorus diffusion under nonequilibrium conditions are extracted from the experimental results. A cluster-mediated diffusion model is developed using the

The role of phosphorus in chemical evolution.

PubMed

Maciá, Enrique

2005-08-01

In this tutorial review we consider the role of phosphorus and its compounds within the context of chemical evolution in galaxies. Following an interdisciplinary approach we first discuss the position of P among the main biogenic elements by considering its relevance in most essential biochemical functions as well as its peculiar chemistry under different physicochemical conditions. Then we review the phosphorus distribution in different cosmic sites, such as terrestrial planets, interplanetary dust particles, cometary dust, planetary atmospheres and the interstellar medium (ISM). In this way we realize that this element is both scarce and ubiquitous in the universe. These features can be related to the complex nucleosynthesis of P nuclide in the cores of massive stars under explosive conditions favouring a wide distribution of this element through the ISM, where it would be ready to react with other available atoms. A general tendency towards more oxidized phosphorus compounds is clearly appreciated as chemical evolution proceeds from circumstellar and ISM materials to protoplanetary and planetary condensed matter phases. To conclude we discuss some possible routes allowing for the incorporation of phosphorus compounds of prebiotic interest during the earlier stages of solar system formation.

Osteophagia provide giraffes with phosphorus and calcium?

PubMed

Bredin, I P; Skinner, J D; Mitchell, G

2008-03-01

The daily requirement for calcium and phosphorus by giraffes to sustain the growth and maintenance of their skeletons is large. The source of sufficient calcium is browse. The source of necessary phosphorus is obscure, but it could be osteophagia, a frequently observed behaviour in giraffes. We have assessed whether bone ingested as a result of osteophagia can be digested in the rumen. Bone samples from cancellous (cervical vertebrae) and dense bones (metacarpal shaft) were immersed in the rumens of five sheep, for a period of up to 30 days, and the effect compared to immersion in distilled water and in artificial saliva for 30 days. Distilled water had no effect on the bones. Dense bone samples were softened by exposure to the saliva and rumen fluid, but did not lose either calcium or phosphorus. In saliva and rumen fluid the cancellous bone samples also softened, and their mass and volume decreased as a result of exposure to saliva, but in neither fluid did they lose significant amounts of calcium and phosphorus. We conclude that although saliva and rumen fluid can soften ingested bones, there is an insignificant digestion of bones in the rumen.

[Phosphorus removal characteristics by aerobic granules in normal molasses wastewater after anaerobic treatment].

PubMed

Wang, Shuo; Yu, Shui-Li; Shi, Wen-Xin; Bao, Rui-Ling; Yi, Xue-Song; Li, Jian-Zheng

2012-04-01

COD decreased obviously in normal molasses wastewater after anaerobic treatment, however, concentrations of nitrogen and phosphorus were still higher in the effluent which seriously damaged the ecological balance. In this study, aerobic granules cultivated in sequencing batch airlift reactor (SBAR) were carried out for treating the effluent; phosphorus removal processes and characteristics were discussed as well. The mean diameter of aerobic granules cultivated by multiple carbon sources (acetate, propionate and butyrate) was 1.7 mm. The average phosphorus removal efficiency was 90.9% and the level of phosphorus in effluent was only 1.3 mg x L(-1); TP released per COD consumed was 0.571 and the specific rate of TP released was 5.73 mg x (g x h)(-1). NO3(-) -N usage of phosphorus accumulating organisms (PAOs) improved during denitrifying process because the concentration of propionate and butyrate increased in multiple carbon sources which means the phosphorus uptake efficiency increased when per NO3(-) -N consumed. Phosphorus content represented a stronger correlation with magnesium, calcium and ferrum contents in aerobic granules and their extracellular polymeric substances (EPS), the phosphorus adsorption by EPS could enhance phosphorus removal. 61.9% of phosphorus accumulating organisms were denitrifying phosphorus accumulating organisms in aerobic granules and TP uptake per NO3(-) -N consumed was 1.14 which was higher than that of aerobic granules only cultivated by acetate.

Metabolism of nonparticulate phosphorus in an acid bog lake

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koenings, J. P.

1977-01-01

In North Gate Lake, an acid bog lake located on the northern Michigan-Wisconsin border, U.S.A., the algal nutrient inorganic phosphate (FRP) is not detectable by chemical means. Organic phosphorus (FUP) represents 100% of the detectable filterable phosphorus. The availability and cycling of this organic fraction are of considerable interest in regard to the primary productivity of this system. To clarify these relationships, the cycling of nonparticulate forms of phosphorus found in the epilimnion of this lake was studied.

High dietary phosphorus intake is associated with all-cause mortality: results from NHANES III.

PubMed

Chang, Alex R; Lazo, Mariana; Appel, Lawrence J; Gutiérrez, Orlando M; Grams, Morgan E

2014-02-01

Elevated serum phosphorus is associated with all-cause mortality, but little is known about risk associated with dietary phosphorus intake. We investigated the association between phosphorus intake and mortality in a prospective cohort of healthy US adults (NHANES III; 1998-1994). Study participants were 9686 nonpregnant adults aged 20-80 y without diabetes, cancer, or kidney or cardiovascular disease. Exposure to dietary phosphorus, which was assessed by using a 24-h dietary recall, was expressed as the absolute intake and phosphorus density (phosphorus intake divided by energy intake). All-cause and cardiovascular mortality was assessed through 31 December 2006. Median phosphorus intake was 1166 mg/d (IQR: 823-1610 mg/d); median phosphorus density was 0.58 mg/kcal (0.48-0.70 mg/kcal). Individuals who consumed more phosphorus-dense diets were older, were less often African American, and led healthier lifestyles (smoking, physical activity, and Healthy Eating Index). In analyses adjusted for demographics, cardiovascular risk factors, kidney function, and energy intake, higher phosphorus intake was associated with higher all-cause mortality in individuals who consumed >1400 mg/d [adjusted HR (95% CI): 2.23 (1.09, 4.5) per 1-unit increase in ln(phosphorus intake); P = 0.03]. At <1400 mg/d, there was no association. A similar association was seen between higher phosphorus density and all-cause mortality at a phosphorus density amount >0.35 mg/kcal [adjusted HR (95% CI): 2.27 (1.19, 4.33) per 0.1-mg/kcal increase in phosphorus density; P = 0.01]. At <0.35 mg/kcal (approximately the fifth percentile), lower phosphorus density was associated with increased mortality risk. Phosphorus density was associated with cardiovascular mortality [adjusted HR (95% CI): 3.39 (1.43, 8.02) per 0.1 mg/kcal at >0.35 mg/kcal; P = 0.01], whereas no association was shown in analyses with phosphorus intake. Results were similar by subgroups of diet quality and in analyses adjusted for sodium

Method of removing and detoxifying a phosphorus-based substance

DOEpatents

Vandegrift, George F.; Steindler, Martin J.

1989-01-01

A method of removing organic phosphorus-based poisonous substances from water contaminated therewith and of subsequently destroying the toxicity of the substance is disclosed. Initially, a water-immiscible organic is immobilized on a supported liquid membrane. Thereafter, the contaminated water is contacted with one side of the supported liquid membrane to selectively dissolve the phosphorus-based substance in the organic extractant. At the same time, the other side of the supported liquid membrane is contacted with a hydroxy-affording strong base to react the phosphorus-based substance dissolved by the organic extractant with a hydroxy ion. This forms a non-toxic reaction product in the base. The organic extractant can be a water-insoluble trialkyl amine, such as trilauryl amine. The phosphorus-based substance can be phosphoryl or a thiophosphoryl.

Phosphorus-containing nucleophiles in reactions with polyfluorinated organic compounds

NASA Astrophysics Data System (ADS)

Furin, Georgii G.

1993-03-01

The review presents a compilation of new expelimental data on the reactions of phosphorus-containing nucleophiles [triphenylphosphine, trialkylphosphines, trialkyl phosphites, phosphorus tris(diethylamide), etc.] with perfluorinated olefins and aromatic and heterocyclic compounds, leading to substances both with and without a phosphorus atom. It is shown that the interaction of phosphorus tris(diethylamide) and trialkylphosphines with organic polyfluoro-compounds and perfluoroolefins leads to the formation of phosphoranes, the decomposition of which is accompanied by the generation of aryl and alkenyl anions. The reactions of these anions with C-electrophiles and compounds containing mobile halogen atoms are examined. In addition, the pathways in the Arbuzov reaction involving a series of unsaturated perfluorinated compounds are analysed. Possible applications of these reactions in organic synthesis are demonstrated. The bibliography includes 120 references.

Pervasive phosphorus limitation of tree species but not communities in tropical forests

NASA Astrophysics Data System (ADS)

Turner, Benjamin L.; Brenes-Arguedas, Tania; Condit, Richard

2018-03-01

Phosphorus availability is widely assumed to limit primary productivity in tropical forests, but support for this paradigm is equivocal. Although biogeochemical theory predicts that phosphorus limitation should be prevalent on old, strongly weathered soils, experimental manipulations have failed to detect a consistent response to phosphorus addition in species-rich lowland tropical forests. Here we show, by quantifying the growth of 541 tropical tree species across a steep natural phosphorus gradient in Panama, that phosphorus limitation is widespread at the level of individual species and strengthens markedly below a threshold of two parts per million exchangeable soil phosphate. However, this pervasive species-specific phosphorus limitation does not translate into a community-wide response, because some species grow rapidly on infertile soils despite extremely low phosphorus availability. These results redefine our understanding of nutrient limitation in diverse plant communities and have important implications for attempts to predict the response of tropical forests to environmental change.

Psr1, a nuclear localized protein that regulates phosphorus metabolism in Chlamydomonas.

PubMed

Wykoff, D D; Grossman, A R; Weeks, D P; Usuda, H; Shimogawara, K

1999-12-21

Understanding the ways in which phosphorus metabolism is regulated in photosynthetic eukaryotes is critical for optimizing crop productivity and managing aquatic ecosystems in which phosphorus can be a major source of pollution. Here we describe a gene encoding a regulator of phosphorus metabolism, designated Psr1 (phosphorus starvation response), from a photosynthetic eukaryote. The Psr1 protein is critical for acclimation of the unicellular green alga Chlamydomonas reinhardtii to phosphorus starvation. The N-terminal half of Psr1 contains a region similar to myb DNA-binding domains and the C-terminal half possesses glutamine-rich sequences characteristic of transcriptional activators. The level of Psr1 increases at least 10-fold upon phosphate starvation, and immunocytochemical studies demonstrate that this protein is nuclear-localized under both nutrient-replete and phosphorus-starvation conditions. Finally, Psr1 and angiosperm proteins have domains that are similar, suggesting a possible role for Psr1 homologs in the control of phosphorus metabolism in vascular plants. With the identification of regulators such as Psr1 it may become possible to engineer photosynthetic organisms for more efficient utilization of phosphorus and to establish better practices for the management of agricultural lands and natural ecosystems.

Phosphorus-containing food additives and the accuracy of nutrient databases: implications for renal patients.

PubMed

Sullivan, Catherine M; Leon, Janeen B; Sehgal, Ashwini R

2007-09-01

Phosphorus-containing additives are increasingly being added to food products. We sought to determine the potential impact of these additives. We focused on chicken products as an example. We purchased a variety of chicken products, prepared them according to package directions, and performed laboratory analyses to determine their actual phosphorus content. We used ESHA Food Processor SQL Software (version 9.8, ESHA Research, Salem, OR) to determine the expected phosphorus content of each product. Of 38 chicken products, 35 (92%) had phosphorus-containing additives listed among their ingredients. For every category of chicken products containing additives, the actual phosphorus content was greater than the content expected from nutrient database. For example, actual phosphorus content exceeded expected phosphorus content by an average of 84 mg/100 g for breaded breast strips. There was also a great deal of variation within each category. For example, the difference between actual and expected phosphorus content ranged from 59-165 mg/100 g for breast patties. Two 100-g servings of additive-containing products contained, on average, 440 mg of phosphorus, or about half the total daily recommended intake for dialysis patients. Phosphorus-containing additives significantly increase the amount of phosphorus in chicken products. Available nutrient databases do not reflect this higher phosphorus content, and the variation between similar products makes it impossible for patients and dietitians to accurately estimate phosphorus content. We recommend that dialysis patients limit their intake of additive-containing products, and that the phosphorus content of food products be included on nutrition facts labels.

PHOSPHORUS CONTAINING FOOD ADDITIVES AND THE ACCURACY OF NUTRIENT DATABASES: IMPLICATIONS FOR RENAL PATIENTS

PubMed Central

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

2007-01-01

Objective Phosphorus containing additives are increasingly added to food products. We sought to determine the potential impact of these additives. We focused on chicken products as an example. Methods We purchased a variety of chicken products, prepared them according to package directions, and performed laboratory analyses to determine their actual phosphorus content. We used ESHA Food Processor SQL Software to determine the expected phosphorus content of each product. Results Of 38 chicken products, 35 (92%) had phosphorus containing additives listed among their ingredients. For every category of chicken products containing additives, the actual phosphorus content was greater than the content expected from nutrient database. For example, actual phosphorus content exceeded expected phosphorus content by an average of 84 mg/100g for breaded breast strips. There was also a great deal of variation within each category. For example, the difference between actual and expected phosphorus content ranged from 59 to 165 mg/100g for breast patties. Two 100 g servings of additive containing products contain an average of 440 mg of phosphorus, or about half the total daily recommended intake for dialysis patients. Conclusion Phosphorus containing additives significantly increase the amount of phosphorus in chicken products. Available nutrient databases do not reflect this higher phosphorus content, and the variation between similar products makes it impossible for patients and dietitians to accurately estimate phosphorus content. We recommend that dialysis patients limit their intake of additive containing products and that the phosphorus content of food products be included on nutrition facts labels. PMID:17720105

λ5-Phosphorus-Containing α-Diazo Compounds: A Valuable Tool for Accessing Phosphorus-Functionalized Molecules.

PubMed

Marinozzi, Maura; Pertusati, Fabrizio; Serpi, Michaela

2016-11-23

The compounds characterized by the presence of a λ 5 -phosphorus functionality at the α-position with respect to the diazo moiety, here referred to as λ 5 -phosphorus-containing α-diazo compounds (PCDCs), represent a vast class of extremely versatile reagents in organic chemistry and are particularly useful in the preparation of phosphonate- and phosphinoxide-functionalized molecules. Indeed, thanks to the high reactivity of the diazo moiety, PCDCs can be induced to undergo a wide variety of chemical transformations. Among them are carbon-hydrogen, as well as heteroatom-hydrogen insertion reactions, cyclopropanation, ylide formation, Wolff rearrangement, and cycloaddition reactions. PCDCs can be easily prepared from readily accessible precursors by a variety of different methods, such as diazotization, Bamford-Stevens-type elimination, and diazo transfer reactions. This evidence along with their relative stability and manageability make them appealing tools in organic synthesis. This Review aims to demonstrate the ongoing utility of PCDCs in the modern preparation of different classes of phosphorus-containing compounds, phosphonates, in particular. Furthermore, to address the lack of precedent collective papers, this Review also summarizes the methods for PCDCs preparation.

Red Phosphorus for Use in Screening Smoke Compositions

DTIC Science & Technology

1999-02-01

weight % paraffin oil, or mineral oil, or silicon oil, or 20 to 50 weight % pentaerithritol based on the nitrogen compound. Kaiser and Cadus (BASF)27...impregnated red phosphorus. Kaiser O and Cadus A BASF AG US 3,951,908 (1974) III References 28 Desensitised free-flowing red phosphorus. Wortmann J

Simulation of Nitrogen and Phosphorus Losses in Loess Landforms of Northern Iran

NASA Astrophysics Data System (ADS)

Kiani, F.; Behtarinejad, B.; Najafinejad, A.; Kaboli, R.

2018-02-01

Population growth, urban expansion and intensive agriculture and thus increased use of fertilizers aimed at increasing the production capacity cause extensive loss of nutrients such as nitrogen and phosphorus and lead to reduced quality of soil and water. Therefore, identification of nutrients in the soil and their potential are essential. The aim of this study was to evaluate the capability of the SWAT model in simulating runoff, sediment, and nitrogen and phosphorus losses in Tamer catchment. Runoff and sediment measured at Tamar gauging station were used to calibrate and validate the model. Simulated values were generally consistent with the data observed during calibration and validation period (0.6 < R 2 and 0.5 < NS). In the case of nitrogen loss, the model performed an almost good simulation (0.6 < R 2 and 0.47 < NS), but phosphorus simulation yielded better results (0.76 < R 2 and 0.66 < NS). The results showed that cultivated lands had higher loss of nitrogen and phosphorus than other types of land use. Among the various forms of nitrogen and phosphorus, the loss of organic nitrogen and nitrate and soluble phosphorus and mineral phosphorus attached to the sediments showed the greatest sensitivity to the type of land use. Results also showed that the average nutrient loss caused by erosion in this catchment, was 6.99 kg/ha for nitrogen, 0.35 kg/ha for nitrate, 1.3 kg/ha for organic phosphorus, 0.015 kg/ha for soluble phosphorus, and 0.45 kg/ha for mineral phosphorus.

Pressure-induced zigzag phosphorus chain and superconductivity in boron monophosphide.

PubMed

Zhang, Xinyu; Qin, Jiaqian; Liu, Hanyu; Zhang, Shiliang; Ma, Mingzhen; Luo, Wei; Liu, Riping; Ahuja, Rajeev

2015-03-04

We report on the prediction of the zinc-blende structure BP into a novel C2/m phase from 113 to 208 GPa which possesses zigzag phosphorus chain structure, followed by another P42/mnm structure above 208 GPa above using the particle-swarm search method. Strong electron-phonon coupling λ in compressed BP is found, in particular for C2/m phase with the zigzag phosphorus chain, which has the highest λ (0.56-0.61) value among them, leading to its high superconducting critical temperature Tc (9.4 K-11.5 K), which is comparable with the 4.5 K to 13 K value of black phosphorus phase I (orthorhombic, Cmca). This is the first system in the boron phosphides which shows superconductivity from the present theoretical calculations. Our results show that pressure-induced zigzag phosphorus chain in BP exhibit higher superconducting temperature TC, opening a new route to search and design new superconductor materials with zigzag phosphorus chains.

Transport properties of ultrathin black phosphorus on hexagonal boron nitride

DOE Office of Scientific and Technical Information (OSTI.GOV)

Doganov, Rostislav A.; Özyilmaz, Barbaros; Department of Physics, National University of Singapore, 2 Science Drive 3, 117542 Singapore

2015-02-23

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 SiO{sub 2} 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 explainmore » 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 SiO{sub 2} substrates and reduces the hysteresis at room temperature.« less

Modeling of phosphorus fluxes produced by wild fires at watershed scales.

NASA Astrophysics Data System (ADS)

Matyjasik, M.; Hernandez, M.; Shaw, N.; Baker, M.; Fowles, M. T.; Cisney, T. A.; Jex, A. P.; Moisen, G.

2017-12-01

River runoff is one of the controlling processes in the terrestrial phosphorus cycle. Phosphorus is often a limiting factor in fresh water. One of the factors that has not been studied and modeled in detail is phosporus flux produced from forest wild fires. Phosphate released by weathering is quickly absorbed in soils. Forest wild fires expose barren soils to intensive erosion, thus releasing relatively large fluxes of phosphorus. Measurements from three control burn sites were used to correlate erosion with phosphorus fluxes. These results were used to model phosphorus fluxes from burned watersheds during a five year long period after fires occurred. Erosion in our model is simulated using a combination of two models: the WEPP (USDA Water Erosion Prediction Project) and the GeoWEPP (GIS-based Water Erosion Prediction Project). Erosion produced from forest disturbances is predicted for any watershed using hydrologic, soil, and meteorological data unique to the individual watersheds or individual slopes. The erosion results are modified for different textural soil classes and slope angles to model fluxes of phosphorus. The results of these models are calibrated using measured concentrations of phosphorus for three watersheds located in the Interior Western United States. The results will help the United States Forest Service manage phosporus fluxes in national forests.

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

... 1117-AA66 Chemical Mixtures Containing Listed Forms of Phosphorus and Change in Application Process... phosphorus, white phosphorus (also known as yellow phosphorus), or hypophosphorous acid and its salts (hereinafter ``regulated phosphorus'') that shall automatically qualify for exemption from the Controlled...

Utilizing Wetlands for Phosphorus Reduction in Great Lakes Watersheds: A Review of Available Literature Examining Soil Properties and Phosphorus Removal Efficiency

DTIC Science & Technology

2017-10-01

phosphorus inputs in a variety of agricultural and urban settings. However, maximizing the efficiency and benefits of wetlands for phosphorus reduction...39 Appendix B: Citations Related To P In Agricultural Landscapes...priority areas exhibiting high P export rates associated with agricultural and other land use practices (Figure 2). The GLRI Action Plan recommended

Carbanion-Accelerated Claisen Rearrangements Asymmetric Induction with Chiral Phosphorus-Stabilized Anions‡

PubMed Central

Denmark, Scott E.; Marlin, John E.; Rajendra, G.

2012-01-01

The carbanion-accelerated Claisen rearrangement has been extended to include phosphorus carbanion-stabilizing groups. The appropriately substituted allyl vinyl ethers are synthesized by the nucleophilic addition of allyloxides to phosphorus-substituted allenes, which are obtained in one step from simple starting materials. The phosphorus-stabilized, carbanion-accelerated Claisen rearrangements proceed rapidly at room temperature in high yield, and the rearrangements are highly site and stereoselective. The first examples of asymmetric induction in the Claisen rearrangement with chiral, phosphorus, anion-stabilizing groups are described. The observed asymmetric induction is highly dependent on the structure of the auxiliary and the metal counterion involved. Both internal and relative diastereoselectivity are high. A model for the observed sense of internal diastereoselectivity is proposed that is founded in the current understanding of the structure of phosphorus-stabilized anions. PMID:23101563

PHOSPHORUS-BEARING MOLECULES IN MASSIVE DENSE CORES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fontani, F.; Rivilla, V. M.; Caselli, P.

2016-05-10

Phosphorus is a crucial element for the development of life, but so far P-bearing molecules have been detected only in a few astrophysical objects; hence, its interstellar chemistry is almost totally unknown. Here, we show new detections of phosphorus nitride (PN) in a sample of dense cores in different evolutionary stages of the intermediate- and high-mass star formation process: starless, with protostellar objects, and with ultracompact H ii regions. All detected PN line widths are smaller than ≃5 km s{sup −1}, and they arise from regions associated with kinetic temperatures smaller than 100 K. Because the few previous detections reportedmore » in the literature are associated with warmer and more turbulent sources, the results of this work show that PN can arise from relatively quiescent and cold gas. This information is challenging for theoretical models that invoke either high desorption temperatures or grain sputtering from shocks to release phosphorus into the gas phase. Derived column densities are of the order of 10{sup 11–12} cm{sup −2}, marginally lower than the values derived in the few high-mass star-forming regions detected so far. New constraints on the abundance of phosphorus monoxide, the fundamental unit of biologically relevant molecules, are also given.« less

Recovery of high purity phosphorus from municipal wastewater secondary effluent by a high-speed adsorbent.

PubMed

Midorikawa, I; Aoki, H; Omori, A; Shimizu, T; Kawaguchi, Y; Kassai, K; Murakami, T

2008-01-01

High purity phosphorus was recovered from municipal wastewater secondary effluent as phosphate, using a newly developed phosphorus adsorption and recovery system. A high-speed adsorbent having a unique porous structure was used in this system. The secondary effluent, showing total phosphorus (TP) of 0.1-2.1 mg P/L, was passed through an adsorbent packed column at high space velocity (SV) of 15 h(-1). The TP of the treated water was as low as 0.02-0.04 mg P/L, indicating that 97% of phosphorus in the secondary effluent was removed. The removed phosphorus was desorbed from the adsorbent by passing a sodium hydroxide aqueous solution through the column. Calcium hydroxide was added to this solution to precipitate the phosphorus as calcium phosphate. This precipitate was neutralized with hydrochloric acid aqueous solution, washed with water, and then solid-liquid separation was performed for the phosphorus recovery. The main constituent of the recovered phosphorus was apatite-type calcium phosphate, with 16% phosphorus content, which matched that of high-grade phosphorus ore. The hazardous elements content of the recovered phosphorus was exceedingly low. Therefore the recovered phosphorus can be applied to an alternative for phosphorus ore, or to a phosphate fertilizer. IWA Publishing 2008.

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

Phosphorus and nitrogen regulate arbuscular mycorrhizal symbiosis in Petunia hybrida.

PubMed

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.

Nano-rod Ca-decorated sludge derived carbon for removal of phosphorus.

PubMed

Kong, Lingjun; Han, Meina; Shih, Kaimin; Su, Minhua; Diao, Zenghui; Long, Jianyou; Chen, Diyun; Hou, Li'an; Peng, Yan

2018-02-01

Recovering phosphorus (P) from waste streams takes the unique advantage in simultaneously addressing the crisis of eutrophication and the shortage of P resource. A novel calcium decorated sludge carbon (Ca-SC) was developed from dyeing industry wastewater treatment sludge by decorating calcium (Ca) to effectively adsorb phosphorus from solution. The X-ray diffraction (XRD) and Fourier transform infrared (FTIR) techniques were used to characterize the Ca-SCs, followed by isotherm and kinetic sorption experiments. A preferred design with CaCO 3 to sludge mass ratio of 1:2 was found to have a sorption capacity of 116.82 mg/g for phosphorus. This work reveals the crucial role of well-dispersed nano-rod calcium on the Ca-SC surface for the sorption of phosphorus. Moreover, the decoration of nano-rod calcium was found to further promote the uptake of phosphorus through the formation of hydroxylapatite (Ca 5 (PO 4 ) 3 (OH)). Thus, the development of decorated Ca-SC for sorption of phosphorus is very important in solving the P pollution and resource loss. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparison of phosphorus recovery from incineration and gasification sewage sludge ash.

PubMed

Parés Viader, Raimon; Jensen, Pernille Erland; Ottosen, Lisbeth M; Thomsen, Tobias P; Ahrenfeldt, Jesper; Hauggaard-Nielsen, Henrik

2017-03-01

Incineration of sewage sludge is a common practice in many western countries. Gasification is an attractive option because of its high energy efficiency and flexibility in the usage of the produced gas. However, they both unavoidably produce sewage sludge ashes, a material that is rich in phosphorus, but which is commonly landfilled or used in construction materials. With current uncertainty in phosphate rock supply, phosphorus recovery from sewage sludge ashes has become interesting. In the present work, ashes from incineration and gasification of the same sewage sludge were compared in terms of phosphorus extractability using electrodialytic (ED) methods. The results show that comparable recovery rates of phosphorus were achieved with a single ED step for incineration ashes and a sequential combination of two ED steps for gasification ashes, which was due to a higher influence of iron and/or aluminium in phosphorus solubility for the latter. A product with lower level of metallic impurities and comparable to wet process phosphoric acid was eventually obtained from gasification ashes. Thus, gasification becomes an interesting alternative to incineration also in terms of phosphorus separation.

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

Hydrologic and biogeochemical controls on phosphorus export from western Lake Erie tributaries

USDA-ARS?s Scientific Manuscript database

Understanding the processes controlling phosphorus (P) export from agricultural watersheds is essential for predicting and mitigating adverse environmental impacts. In this study, discharge, dissolved reactive phosphorus load, and total phosphorus load time series data (1975-2014) from two Lake Erie...

Phosphorus doped graphene by inductively coupled plasma and triphenylphosphine treatments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shin, Dong-Wook, E-mail: shindong37@skku.edu; Kim, Tae Sung; Yoo, Ji-Beom, E-mail: jbyoo@skku.edu

Highlights: • Substitution doping is a promising method for opening the energy band gap of graphene. • Substitution doping with phosphorus in the graphene lattice has numerous advantage such as high band gap, low formation energy, and high net charge density compared to nitrogen. • V{sub dirac} of Inductively coupled plasma (ICP) and triphenylphosphine (TPP) treated graphene was −57 V, which provided clear evidence of n-type doping. • Substitutional doping of graphene with phosphorus is verified by the XPS spectra of P 2p core level and EELS mapping of phosphorus. • The chemical bonding between P and graphene is verymore » stable for a long time in air (2 months). - Abstract: Graphene is considered a host material for various applications in next-generation electronic devices. However, despite its excellent properties, one of the most important issues to be solved as an electronic material is the creation of an energy band gap. Substitution doping is a promising method for opening the energy band gap of graphene. Herein, we demonstrate the substitutional doping of graphene with phosphorus using inductively coupled plasma (ICP) and triphenylphosphine (TPP) treatments. The electrical transfer characteristics of the phosphorus doped graphene field effect transistor (GFET) have a V{sub dirac} of ∼ − 54 V. The chemical bonding between P and C was clearly observed in XPS spectra, and uniform distribution of phosphorus within graphene domains was confirmed by EELS mapping. The capability for substitutional doping of graphene with phosphorus can significantly promote the development of graphene based electronic devices.« less

Soil phosphorus availability differences between sprinkler and furrow irrigation

USDA-ARS?s Scientific Manuscript database

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...

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.

Selenium toxicity in plants and its detoxification by phosphorus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, M.; Singh, N.

1978-11-01

A study was undertaken to determine selenium toxicity and the effect of phosphorus application on selenium in wheat (Triticum aestivum). Selenium in a compound was applied at 0, 2.5, 5, and 10 ppm to wheat in a greenhouse using sandy soil. Phosphorus in a compound was applied at 0, 50, and 100 ppm to the experimental plants. Sunflower (Helianthus annuus) was grown after wheat to determine the residual effect of selenium and phosphorus. Results indicated that high amounts (2.5 ppm and above) of added and residual selenium in soil decreased the growth of wheat and sunflower, decreased the absorption ofmore » zinc, copper, iron, manganese, sulfur, and nitrogen, and decreased the synthesis of nucleic acids, chlorophyll, and protein. The application of phosphorus decreased the harmful effects of selenium and increased all the above parameters. (3 graphs, 21 references, 4 tables)« less

Atomic and electronic structure of exfoliated black phosphorus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Ryan J.; Topsakal, Mehmet; Jeong, Jong Seok

2015-11-15

Black phosphorus, a layered two-dimensional crystal with tunable electronic properties and high hole mobility, is quickly emerging as a promising candidate for future electronic and photonic devices. Although theoretical studies using ab initio calculations have tried to predict its atomic and electronic structure, uncertainty in its fundamental properties due to a lack of clear experimental evidence continues to stymie our full understanding and application of this novel material. In this work, aberration-corrected scanning transmission electron microscopy and ab initio calculations are used to study the crystal structure of few-layer black phosphorus. Directly interpretable annular dark-field images provide a three-dimensional atomic-resolutionmore » view of this layered material in which its stacking order and all three lattice parameters can be unambiguously identified. In addition, electron energy-loss spectroscopy (EELS) is used to measure the conduction band density of states of black phosphorus, which agrees well with the results of density functional theory calculations performed for the experimentally determined crystal. Furthermore, experimental EELS measurements of interband transitions and surface plasmon excitations are also consistent with simulated results. Finally, the effects of oxidation on both the atomic and electronic structure of black phosphorus are analyzed to explain observed device degradation. The transformation of black phosphorus into amorphous PO{sub 3} or H{sub 3}PO{sub 3} during oxidation may ultimately be responsible for the degradation of devices exposed to atmosphere over time.« less

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

PubMed

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

2015-01-20

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.

Phosphorus Sorption Capacity of Gray Forest Soil as Dependent on Fertilization System

NASA Astrophysics Data System (ADS)

Rogova, O. B.; Kolobova, N. A.; Ivanov, A. L.

2018-05-01

In this paper, the results of the study of changes in the phosphorus sorption capacity of gray forest soils of Vladimir opolie under the impact of different fertilization systems are discussed. The quantitative parameters of the potential buffer capacity of soils for phosphorus (PBCP) and Langmuir sorption isotherms have been calculated. It is shown that the application of organic fertilizers results in a stronger decrease in PBCP than the application of mineral fertilizers. The portion of phosphorus of mineral compounds considerably increases, and the high content of available phosphates is maintained. In the variants with application of mineral phosphorus in combination with manure, the portions of organic and mineral phosphorus are at the level typical of unfertilized soils. The energy of phosphate bonds with the soil is minimal upon the application of a double rate of mineral phosphorus at the maximum capacity in relation to phosphate ions.

Electronic transport properties of suspended few-nm black phosphorus nanoribbons

NASA Astrophysics Data System (ADS)

Masih Das, Paul; Danda, Gopinath; Cupo, Andrew; Jothi Thiruraman, Priyanka; Meunier, Vincent; Drndic, Marija

Theoretical studies of few-nm wide black phosphorus nanoribbons have revealed highly tunable, width-dependent properties such as modulation of bandgap magnitude and carrier mobility. Due to the atmospheric instability of black phosphorus in the few-layer regime and a lack of suitable lithographic patterning techniques, these structures have yet to be reported. Here, we demonstrate the fabrication of few-nm wide and thick black phosphorus nanoribbons via in situ electron beam nanosculpting. We also present in situ orientation- and width-dependent two-terminal electronic transport measurements of these structures. These measurements yield valuable insight into the semiconducting properties of black phosphorus and its associated lower-dimensional nanostructures. NIH Grant R21HG007856, NSF Grant EFRI 2-DARE (EFRI-1542707).

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.

Reducing watershed scale phosphorus export through integrated management practices

USDA-ARS?s Scientific Manuscript database

Phosphorus losses from golf course have been documented and are comparable to losses from agriculture and urban areas. Integrated management practices are required to address the problem. An integrated management approach using filter socks and limiting the amount of phosphorus applied to the golf c...

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

USDA-ARS?s Scientific Manuscript database

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...

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

USDA-ARS?s Scientific Manuscript database

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...

Effect of phosphorus on biodiesel production from Scenedesmus obliquus under nitrogen-deficiency stress.

PubMed

Chu, Fei-Fei; Chu, Pei-Na; Shen, Xiao-Fei; Lam, Paul K S; Zeng, Raymond J

2014-01-01

In order to study the effect of phosphorus on biodiesel production from Scenedesmus obliquus especially under nitrogen deficiency conditions, six types of media with combinations of nitrogen repletion/depletion and phosphorus repletion/limitation/depletion were investigated in this study. It was found that nitrogen starvation compared to nitrogen repletion enhanced biodiesel productivity. Moreover, biodiesel productivity was further strengthened by varying the supply level of phosphorus from depletion, limitation, through to repletion. The maximum FAMEs productivity of 24.2 mg/L/day was obtained in nitrogen depletion with phosphorus repletion, which was two times higher than that in nutrient complete medium. More phosphorus was accumulated in cells under the nitrogen starvation with sufficient phosphorus condition, but no polyphosphate was formed. This study indicated that nitrogen starvation plus sufficient P supply might be the real "lipid trigger". Furthermore, results of the current study suggest a potential application for utilizing microalgae to combine phosphorus removal from wastewater with biodiesel production. Copyright © 2013 Elsevier Ltd. All rights reserved.

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.

[Effects of carbon sources, temperature and electron acceptors on biological phosphorus removal].

PubMed

Han, Yun; Xu, Song; Dong, Tao; Wang, Bin-Fan; Wang, Xian-Yao; Peng, Dang-Cong

2015-02-01

Effects of carbon sources, temperature and electron acceptors on phosphorus uptake and release were investigated in a pilot-scale oxidation ditch. Phosphorus uptake and release rates were measured with different carbon sources (domestic sewage, sodium acetate, glucose) at 25 degrees C. The results showed that the minimum phosphorus uptake and release rates of glucose were 5.12 mg x (g x h)(-1) and 6.43 mg x (g x h)(-1), respectively, and those of domestic sewage are similar to those of sodium acetate. Phosphorus uptake and release rates increased with the increase of temperature (12, 16, 20 and 25 degrees C) using sodium acetate as carbon sources. Anoxic phosphorus uptake rate decreased with added COD. Electron acceptors (oxygen, nitrate, nitrite) had significant effects on phosphorus uptake rate and their order was in accordance with oxygen > nitrate > nitrite. The mass ratio of anoxic P uptake and N consumption (P(uptake)/N (consumption)) of nitrate and nitrite were 0.96 and 0.65, respectively.

A Quantitative NMR Analysis of Phosphorus in Carbonaceous and Ordinary Chondrites

NASA Technical Reports Server (NTRS)

Pasek, M. A.; Smith, V. D.; Lauretta, D. S.

2004-01-01

Phosphorus is important in a number of biochemical molecules, from DNA to ATP. Early life may have depended on meteorites as a primary source of phosphorus as simple dissolution of crustal apatite may not produce the necessary concentration of phosphate. Phosphorus is found in several mineral phases in meteorites. Apatite and other Ca- and Mg phosphate minerals tend to be the dominant phosphorus reservoir in stony meteorites, whereas in more iron-rich or reduced meteorites, the phosphide minerals schreibersite, (Fe, Ni)3P, and perryite, (Ni, Fe)5(Si, P)2 are dominant. However, in CM chondrites that have experienced significant aqueous alteration, phosphorus has been detected in more exotic molecules. A series of phosphonic acids including methyl-, ethyl-, propyl- and butyl- phosphonic acids were observed by GC-MS in Murchison. Phosphorian sulfides are in Murchison and Murray. NMR spectrometry is capable of detecting multiple substances with one experiment, is non-destructive, and potentially quantitative, as discussed below. Despite these advantages, NMR spectrometry is infrequently applied to meteoritic studies due in large part to a lack of applicability to many compounds and the relatively high limit of detection requirements. Carbon-13 solid-state NMR has been applied to macromolecular carbon in Murchison. P-31 NMR has many advantages over aqueous carbon-13 NMR spectrometry. P-31 is the only isotope of phosphorus, and P-31 gives a signal approximately twice as strong as C-13. These two factors together with the relative abundances of carbon and phosphorus imply that phosphorus should give a signal approximately 20 as strong as carbon in a given sample. A discussion on the preparation of the quantitative standard and NMR studies are presented

Phosphorus doping a semiconductor particle

DOEpatents

Stevens, G.D.; Reynolds, J.S.

1999-07-20

A method of phosphorus doping a semiconductor particle using ammonium phosphate is disclosed. A p-doped silicon sphere is mixed with a diluted solution of ammonium phosphate having a predetermined concentration. These spheres are dried with the phosphorus then being diffused into the sphere to create either a shallow or deep p-n junction. A good PSG glass layer is formed on the surface of the sphere during the diffusion process. A subsequent segregation anneal process is utilized to strip metal impurities from near the p-n junction into the glass layer. A subsequent HF strip procedure is then utilized to removed the PSG layer. Ammonium phosphate is not a restricted chemical, is inexpensive, and does not pose any special shipping, handling, or disposal requirement. 1 fig.

Chromosomal location of traits associated with wheat seedling water and phosphorus use efficiency under different water and phosphorus stresses.

PubMed

Cao, Hong-Xing; Zhang, Zheng-Bin; Sun, Cheng-Xu; Shao, Hong-Bo; Song, Wei-Yi; Xu, Ping

2009-09-18

The objective of this study was to locate chromosomes for improving water and phosphorus-deficiency tolerance of wheat at the seedling stage. A set of Chinese Spring-Egyptian Red wheat substitution lines and their parent Chinese Spring (recipient) and Egyptian Red (donor) cultivars were measured to determine the chromosomal locations of genes controlling water use efficiency (WUE) and phosphorus use efficiency (PUE) under different water and phosphorus conditions. The results underlined that chromosomes 1A, 7A, 7B, and 3A showed higher leaf water use efficiency (WUE(l) = Pn/Tr; Pn = photosynthetic rate; Tr = transpiration rate) under W-P (Hoagland solution with 1/2P), -W-P (Hoagland solution with 1/2P and 10% PEG). Chromosomes 7A, 3D, 2B, 3B, and 4B may carry genes for positive effects on individual plant water use efficiency (WUE(p) = biomass/TWC; TWC = total water consumption) under WP (Hoagland solution), W-P and -W-P treatment. Chromosomes 7A and 7D carry genes for PUE enhancement under WP, -WP (Hoagland solution with 10% PEG) and W-P treatment. Chromosome 7A possibly has genes for controlling WUE and PUE simultaneously, which indicates that WUE and PUE may share the same genetic background. Phenotypic and genetic analysis of the investigated traits showed that photosynthetic rate (Pn) and transpiration rate (Tr), Tr and WUE(l) showed significant positive and negative correlations under WP, W-P, -WP and -W-P, W-P, -WP treatments, respectively. Dry mass (DM), WUE(P), PUT (phosphorus uptake) all showed significant positive correlation under WP, W-P and -WP treatment. PUE and phosphorus uptake (PUT = P uptake per plant) showed significant negative correlation under the four treatments. The results might provide useful information for improving WUE and PUE in wheat genetics.

Using extension phosphorus uptake research to improve Idaho's nutrient management planning program

USDA-ARS?s Scientific Manuscript database

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...

Major role of planktonic phosphate reduction in the marine phosphorus redox cycle

NASA Astrophysics Data System (ADS)

Van Mooy, B. A. S.; Krupke, A.; Dyhrman, S. T.; Fredricks, H. F.; Frischkorn, K. R.; Ossolinski, J. E.; Repeta, D. J.; Rouco, M.; Seewald, J. D.; Sylva, S. P.

2015-05-01

Phosphorus in the +5 oxidation state (i.e., phosphate) is the most abundant form of phosphorus in the global ocean. An enigmatic pool of dissolved phosphonate molecules, with phosphorus in the +3 oxidation state, is also ubiquitous; however, cycling of phosphorus between oxidation states has remained poorly constrained. Using simple incubation and chromatography approaches, we measured the rate of the chemical reduction of phosphate to P(III) compounds in the western tropical North Atlantic Ocean. Colonial nitrogen-fixing cyanobacteria in surface waters played a critical role in phosphate reduction, but other classes of plankton, including potentially deep-water archaea, were also involved. These data are consistent with marine geochemical evidence and microbial genomic information, which together suggest the existence of a vast oceanic phosphorus redox cycle.

New insights into phosphorus management in agriculture--A crop rotation approach.

PubMed

Łukowiak, Remigiusz; Grzebisz, Witold; Sassenrath, Gretchen F

2016-01-15

This manuscript presents research results examining phosphorus (P) management in a soil–plant system for three variables: i) internal resources of soil available phosphorus, ii) cropping sequence, and iii) external input of phosphorus (manure, fertilizers). The research was conducted in long-term cropping sequences with oilseed rape (10 rotations) and maize (six rotations) over three consecutive growing seasons (2004/2005, 2005/2006, and 2006/2007) in a production farm on soils originated from Albic Luvisols in Poland. The soil available phosphorus pool, measured as calcium chloride extractable P (CCE-P), constituted 28% to 67% of the total phosphorus input (PTI) to the soil–plant system in the spring. Oilseed rape and maize dominant cropping sequences showed a significant potential to utilize the CCE-P pool within the soil profile. Cropping sequences containing oilseed rape significantly affected the CCE-P pool, and in turn contributed to the P(TI). The P(TI) uptake use efficiency was 50% on average. Therefore, the CCE-P pool should be taken into account as an important component of a sound and reliable phosphorus balance. The instability of the yield prediction, based on the P(TI), was mainly due to an imbalanced management of both farmyard manure and phosphorus fertilizer. Oilseed rape plants provide a significant positive impact on the CCE-P pool after harvest, improving the productive stability of the entire cropping sequence. This phenomenon was documented by the P(TI) increase during wheat cultivation following oilseed rape. The Unit Phosphorus Uptake index also showed a higher stability in oilseed rape cropping systems compared to rotations based on maize. Cropping sequences are a primary factor impacting phosphorus management. Judicious implementation of crop rotations can improve soil P resources, efficiency of crop P use, and crop yield and yield stability. Use of cropping sequences can reduce the need for external P sources such as farmyard manure

Dissolved organic phosphorus (DOP) and its potential role for ecosystem nutrition

NASA Astrophysics Data System (ADS)

Brödlin, Dominik; Hagedorn, Frank; Kaiser, Klaus

2016-04-01

During ecosystem development and soil formation, primary mineral sources of phosphorus are becoming increasingly depleted. Inorganic phosphorus forms tend to be bound strongly to or within secondary minerals, thus, are hardly available to plants and are not leached from soil. What about organic forms of phosphorus? Since rarely studied, little is known about the fluxes of dissolved organic phosphorus (DOP) forms and their role in the P cycle. However, there is evidence that DOP is composed of some plant-derived organic phosphorus compounds, such as phytate, which are less mobile and prone to be sorbed to mineral surfaces, whereas microbial-derived compounds like nucleic acids and simple phospho-monoester may represent more mobile forms of soil phosphorus. In our study, we estimated fluxes, composition, and bioavailability of DOP along a gradient in phosphorus availability at five sites on silicate bedrock across Germany (Bad Brückenau, Conventwald, Vessertal, Mitterfels and Lüss) and at a calcareous site in Switzerland (Schänis). Soil solution was collected at 0 down to 60 to 150 cm soil depth at different intervals. Since most solutions had very low P concentrations (<0.05 mg total dissolved P/L), soil solutions had to be concentrated by freeze-drying for the enzymatic characterization of DOP. In order to test the potential bioavailability, we used an enzyme assay distinguishing between phytate-like P (phytate), diester-like P (nucleic acids), monoester-like P (glucose-6-phosphate), and pyrophosphate of bulk molybdate unreactive phosphorus (MUP). First results from the enzymatic assay indicated that monoester-like P and diester-like P were the most prominent form of the hydrolysable DOP constituents. In leachates from the organic layer, there was a high enzymatic activity for monoester-like P, indicating high recycling efficiency and rapid hydrolysis of labile DOP constituents. DOP was the dominating P form in soil solution at some of the sites, with a greater

Phosphorus Elimination at Sodium Silicate from Quartz Sand Roasted with Complexation using Chitosan-EDTA

NASA Astrophysics Data System (ADS)

Wahyuningsih, S.; Ramelan, A. H.; Suharty, N. S.; Handayani, M.; Firdiyono, F.; Sulistiyono, E.; Munawaroh, H.; Sari, P. P.; Kristiawan, Y. R.

2018-03-01

A phosphorus elimination from sodium silicate solution has been studied. Phosphorus elimination was performed by adding chitosan-EDTA to remove cation phosphorus. Characterization of chitosan-EDTA material was performed using FT-IR, while the decreasing level of phosphorus content was analyzed by quantitative analysis using spectrophotometer UV-Vis refers to SNI 06-6989-2004. The results showed that the content of the sodium silicate can be reduced up to 67.1% through Chitosan-EDTA complexation with phosphorus.

Effects of four different phosphorus-locking materials on sediment and water quality in Xi'an moat.

PubMed

Wang, Guanbai; Wang, Yi; Guo, Yu; Peng, Dangcong

2017-01-01

To lower phosphorus concentration in Xi'an moat, four different phosphorus-locking materials, namely, calcium nitrate, sponge-iron, fly ash, and silica alumina clay, were selected in this experiment to study their effects on water quality and sediment. Results of the continuous 68-day experiment showed that calcium nitrate was the most effective for controlling phosphorus concentration in overlying and interstitial water, where the efficiency of locking phosphorus was >97 and 90 %, respectively. Meanwhile, the addition of calcium nitrate caused Fe/Al-bound phosphorus (Fe/Al-P) content in sediment declining but Ca-bound phosphorus (Ca-P) and organic phosphorus (OP) content ascending. The phosphorus-locking efficiency of sponge-iron in overlying and interstitial water was >72 and 66 %, respectively. Meanwhile, the total phosphorus (TP), OP, Fe/Al-P, and Ca-P content in sediment increased by 33.8, 7.7, 23.1, and 23.1 %, respectively, implying that under the action of sponge-iron, the locked phosphorus in sediment was mainly inorganic form and the phosphorus-locking efficiency of sponge-iron could be stable and persistent. In addition, the phosphorus-locking efficiency of fly ash was transient and limited, let alone silica alumina clay had almost no capacity for phosphorus-locking efficiency. Therefore, calcium nitrate and sponge-iron were excellent phosphorus-locking agents to repair the seriously polluted water derived from an internal source.

Phosphorus runoff from incorporated and surface-applied liquid swine manure and phosphorus fertilizer.

PubMed

Daverede, I C; Kravchenko, A N; Hoeft, R G; Nafziger, E D; Bullock, D G; Warren, J J; Gonzini, L C

2004-01-01

Excessive fertilization with organic and/or inorganic P amendments to cropland increases the potential risk of P loss to surface waters. The objective of this study was to evaluate the effects of soil test P level, source, and application method of P amendments on P in runoff following soybean [Glycine max (L.) Merr.]. The treatments consisted of two rates of swine (Sus scrofa domestica) liquid manure surface-applied and injected, 54 kg P ha(-1) triple superphosphate (TSP) surface-applied and incorporated, and a control with and without chisel-plowing. Rainfall simulations were conducted one month (1MO) and six months (6MO) after P amendment application for 2 yr. Soil injection of swine manure compared with surface application resulted in runoff P concentration decreases of 93, 82, and 94%, and P load decreases of 99, 94, and 99% for dissolved reactive phosphorus (DRP), total phosphorus (TP), and algal-available phosphorus (AAP), respectively. Incorporation of TSP also reduced P concentration in runoff significantly. Runoff P concentration and load from incorporated amendments did not differ from the control. Factors most strongly related to P in runoff from the incorporated treatments included Bray P1 soil extraction value for DRP concentration, and Bray P1 and sediment content in runoff for AAP and TP concentration and load. Injecting manure and chisel-plowing inorganic fertilizer reduced runoff P losses, decreased runoff volumes, and increased the time to runoff, thus minimizing the potential risk of surface water contamination. After incorporating the P amendments, controlling erosion is the main target to minimize TP losses from agricultural soils.

Electrodeposition of amorphous ternary nickel-chromium-phosphorus alloy

DOEpatents

Guilinger, Terry R.

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.

Utilization of Glyphosate as Phosphate Source: Biochemistry and Genetics of Bacterial Carbon-Phosphorus Lyase

PubMed Central

Zechel, David L.; Jochimsen, Bjarne

2014-01-01

SUMMARY After several decades of use of glyphosate, the active ingredient in weed killers such as Roundup, in fields, forests, and gardens, the biochemical pathway of transformation of glyphosate phosphorus to a useful phosphorus source for microorganisms has been disclosed. Glyphosate is a member of a large group of chemicals, phosphonic acids or phosphonates, which are characterized by a carbon-phosphorus bond. This is in contrast to the general phosphorus compounds utilized and metabolized by microorganisms. Here phosphorus is found as phosphoric acid or phosphate ion, phosphoric acid esters, or phosphoric acid anhydrides. The latter compounds contain phosphorus that is bound only to oxygen. Hydrolytic, oxidative, and radical-based mechanisms for carbon-phosphorus bond cleavage have been described. This review deals with the radical-based mechanism employed by the carbon-phosphorus lyase of the carbon-phosphorus lyase pathway, which involves reactions for activation of phosphonate, carbon-phosphorus bond cleavage, and further chemical transformation before a useful phosphate ion is generated in a series of seven or eight enzyme-catalyzed reactions. The phn genes, encoding the enzymes for this pathway, are widespread among bacterial species. The processes are described with emphasis on glyphosate as a substrate. Additionally, the catabolism of glyphosate is intimately connected with that of aminomethylphosphonate, which is also treated in this review. Results of physiological and genetic analyses are combined with those of bioinformatics analyses. PMID:24600043

Stable black phosphorus quantum dots for alkali PH sensor

NASA Astrophysics Data System (ADS)

Guo, Weilan; Song, Haizeng; Yan, Shancheng

2018-01-01

Black phosphorus, as a new two-dimensional material has been widely used in sensors, photovoltaic devices, etc. However, thin layered black phosphorus chemically degrades rapidly under ambient and aqueous conditions, which hinders the application of it in the chemical sensors. In this work, stable black phosphorus quantum dots (BPQDs) in solution are successfully synthesized by functionalization with 4-nitrobenzene-diazonium (4-NBD). The stable BPQDs are investigated by TEM, AFM, Raman, and UV-absorption. As a potential application, the stable BPQDs are used as sensors in alkali solution, which exhibit outstanding performance. Our work paves the way towards a new application with BPQDs in solution.

Nature of phosphorus limitation in the ultraoligotrophic eastern Mediterranean.

PubMed

Thingstad, T F; Krom, M D; Mantoura, R F C; Flaten, G A F; Groom, S; Herut, B; Kress, N; Law, C S; Pasternak, A; Pitta, P; Psarra, S; Rassoulzadegan, F; Tanaka, T; Tselepides, A; Wassmann, P; Woodward, E M S; Riser, C Wexels; Zodiatis, G; Zohary, T

2005-08-12

Phosphate addition to surface waters of the ultraoligotrophic, phosphorus-starved eastern Mediterranean in a Lagrangian experiment caused unexpected ecosystem responses. The system exhibited a decline in chlorophyll and an increase in bacterial production and copepod egg abundance. Although nitrogen and phosphorus colimitation hindered phytoplankton growth, phosphorous may have been transferred through the microbial food web to copepods via two, not mutually exclusive, pathways: (i) bypass of the phytoplankton compartment by phosphorus uptake in heterotrophic bacteria and (ii) tunnelling, whereby phosphate luxury consumption rapidly shifts the stoichiometric composition of copepod prey. Copepods may thus be coupled to lower trophic levels through interactions not usually considered.

Nature of Phosphorus Limitation in the Ultraoligotrophic Eastern Mediterranean

NASA Astrophysics Data System (ADS)

Thingstad, T. F.; Krom, M. D.; Mantoura, R. F. C.; Flaten, G. A. F.; Groom, S.; Herut, B.; Kress, N.; Law, C. S.; Pasternak, A.; Pitta, P.; Psarra, S.; Rassoulzadegan, F.; Tanaka, T.; Tselepides, A.; Wassmann, P.; Woodward, E. M. S.; Riser, C. Wexels; Zodiatis, G.; Zohary, T.

2005-08-01

Phosphate addition to surface waters of the ultraoligotrophic, phosphorus-starved eastern Mediterranean in a Lagrangian experiment caused unexpected ecosystem responses. The system exhibited a decline in chlorophyll and an increase in bacterial production and copepod egg abundance. Although nitrogen and phosphorus colimitation hindered phytoplankton growth, phosphorous may have been transferred through the microbial food web to copepods via two, not mutually exclusive, pathways: (i) bypass of the phytoplankton compartment by phosphorus uptake in heterotrophic bacteria and (ii) tunnelling, whereby phosphate luxury consumption rapidly shifts the stoichiometric composition of copepod prey. Copepods may thus be coupled to lower trophic levels through interactions not usually considered.

Iron limitation of microbial phosphorus acquisition in the tropical North Atlantic

PubMed Central

Browning, T. J.; Achterberg, E. P.; Yong, J. C.; Rapp, I.; Utermann, C.; Engel, A.; Moore, C. M.

2017-01-01

In certain regions of the predominantly nitrogen limited ocean, microbes can become co-limited by phosphorus. Within such regions, a proportion of the dissolved organic phosphorus pool can be accessed by microbes employing a variety of alkaline phosphatase (APase) enzymes. In contrast to the PhoA family of APases that utilize zinc as a cofactor, the recent discovery of iron as a cofactor in the more widespread PhoX and PhoD implies the potential for a biochemically dependant interplay between oceanic zinc, iron and phosphorus cycles. Here we demonstrate enhanced natural community APase activity following iron amendment within the low zinc and moderately low iron Western North Atlantic. In contrast we find no evidence for trace metal limitation of APase activity beneath the Saharan dust plume in the Eastern Atlantic. Such intermittent iron limitation of microbial phosphorus acquisition provides an additional facet in the argument for iron controlling the coupling between oceanic nitrogen and phosphorus cycles. PMID:28524880

Hydrology and phosphorus transport simulation in a lowland polder by a coupled modeling system.

PubMed

Yan, Renhua; Huang, Jiacong; Li, Lingling; Gao, Junfeng

2017-08-01

Modeling the rain-runoff processes and phosphorus transport processes in lowland polders is critical in finding reasonable measures to alleviate the eutrophication problem of downstream rivers and lakes. This study develops a lowland Polder Hydrology and Phosphorus modeling System (PHPS) by coupling the WALRUS-paddy model and an improved phosphorus module of a Phosphorus Dynamic model for lowland Polder systems (PDP). It considers some important hydrological characteristics, such as groundwater-unsaturated zone coupling, groundwater-surface water feedback, human-controlled irrigation and discharge, and detailed physical and biochemical cycles of phosphorus in surface water. The application of the model in the Jianwei polder shows that the simulated phosphorus matches well with the measured values. The high precision of this model combined with its low input data requirement and efficient computation make it practical and easy to the water resources management of Chinese polders. Parameter sensitivity analysis demonstrates that K uptake , c Q2 , c W1 , and c Q1 exert a significant effect on the modeled results, whereas K resuspensionMax , K settling , and K mineralization have little effect on the modeled total phosphorus. Among the three types of uncertainties (i.e., parameter, initial condition, and forcing uncertainties), forcing uncertainty produces the strongest effect on the simulated phosphorus. Based on the analysis result of annual phosphorus balance when considering the high import from irrigation and fertilization, lowland polder is capable of retaining phosphorus and reducing phosphorus export to surrounding aquatic ecosystems because of their special hydrological regulation regime. Copyright © 2016 Elsevier Ltd. All rights reserved.

Potential phosphorus eutrophication mitigation strategy: Biochar carbon composition, thermal stability and pH influence phosphorus sorption.

PubMed

Ngatia, L W; Hsieh, Y P; Nemours, D; Fu, R; Taylor, R W

2017-08-01

Phosphorus (P) eutrophication is a major pollution problem globally, with unprecedented amount of P emanating from agricultural sources. But little is known about the optimization of soil-biochar P sorption capacity. The study objective was to determine how biochar feedstocks and pyrolysis conditions influences carbon (C) thermal stability, C composition and pH and in turn influence the phosphorus sorption optimization. Biochar was produced from switchgrass, kudzu and Chinese tallow at 200, 300, 400, 500, 550, 650,750 °C. Carbon thermal stability was determined by multi-element scanning thermal analysis (MESTA), C composition was determined using solid state 13 C NMR. Phosphorus sorption was determined using a mixture of 10% biochar and 90% sandy soil after incubation. Results indicate increased P sorption (P < 0.0001) and decreased P availability (P < 0.0001) with increasing biochar pyrolysis temperature. However, optimum P sorption was feedstock specific with switchgrass indicating P desorption between 200 and 550 °C. Phosphorus sorption was in the order of kudzu > switchgrass > Chinese tallow. Total C, C thermal stability, aromatic C and alkalinity increased with elevated pyrolysis temperature. Biochar alkalinity favored P sorption. There was a positive relationship between high thermal stable C and P sorption for Kudzu (r = 0.62; P = 0.0346) and Chinese tallow (r = 0.73; P = 0.0138). In conclusion, biochar has potential for P eutrophication mitigation, however, optimum biochar pyrolysis temperature for P sorption is feedstock specific and in some cases might be out of 300-500 °C temperature range commonly used for agronomic application. High thermal stable C dominated by aromatic C and alkaline pH seem to favor P sorption. Copyright © 2017 Elsevier Ltd. All rights reserved.

Physiologic volume of phosphorus during hemodialysis: predictions from a pseudo one-compartment model.

PubMed

Leypoldt, John K; Akonur, Alp; Agar, Baris U; Culleton, Bruce F

2012-10-01

The kinetics of plasma phosphorus concentrations during hemodialysis (HD) are complex and cannot be described by conventional one- or two-compartment kinetic models. It has recently been shown by others that the physiologic (or apparent distribution) volume for phosphorus (Vr-P) increases with increasing treatment time and shows a large variation among patients treated by thrice weekly and daily HD. Here, we describe the dependence of Vr-P on treatment time and predialysis plasma phosphorus concentration as predicted by a novel pseudo one-compartment model. The kinetics of plasma phosphorus during conventional and six times per week daily HD were simulated as a function of treatment time per session for various dialyzer phosphate clearances and patient-specific phosphorus mobilization clearances (K(M)). Vr-P normalized to extracellular volume from these simulations were reported and compared with previously published empirical findings. Simulated results were relatively independent of dialyzer phosphate clearance and treatment frequency. In contrast, Vr-P was strongly dependent on treatment time per session; the increase in Vr-P with treatment time was larger for higher values of K(M). Vr-P was inversely dependent on predialysis plasma phosphorus concentration. There was significant variation among predicted Vr-P values, depending largely on the value of K(M). We conclude that a pseudo one-compartment model can describe the empirical dependence of the physiologic volume of phosphorus on treatment time and predialysis plasma phosphorus concentration. Further, the variation in physiologic volume of phosphorus among HD patients is largely due to differences in patient-specific phosphorus mobilization clearance. © 2012 The Authors. Hemodialysis International © 2012 International Society for Hemodialysis.

Dietary egg whites for phosphorus control in maintenance haemodialysis patients: a pilot study.

PubMed

Taylor, Lynn M; Kalantar-Zadeh, Kamyar; Markewich, Theodore; Colman, Sara; Benner, Debbie; Sim, John J; Kovesdy, Csaba P

2011-03-01

High dietary protein intake is associated with greater survival in maintenance haemodialysis (MHD) patients. High-protein foods may increase dietary phosphorus burden, which is associated with increased mortality in these patients. Hypothesis is: an egg white based diet with low phosphorus to protein ratio (<1.4 mg/g) will lower serum phosphorus without deteriorating the nutritional status in MHD patients. We assessed serum phosphorus and albumin levels in MHD patients who agreed to ingest one meal per day with pasteurised liquid egg whites without phosphorus additives, as principal protein source. Thirteen otherwise stable MHD patients with serum phosphorus >4.0 mg/dl agreed to consume eight ounces (225 g) of pasteurised liquid egg whites one meal per day for six weeks. Recipes were suggested to improve diet variety. Thirteen participating patients included seven women, three African Americans and five diabetics. Twelve patients exhibited drop in serum phosphorus. Mean population fall in serum phosphorus was 0.94 mg/dl, i.e. from 5.58 ± 1.34 (mean ± SD) to 4.63 ± 1.18 (p = 0.003). Serum albumin showed an increase by 0.19 g/dl, i.e. from 4.02 ± 0.29 to 4.21 ± 0.36 g/dl (p = 0.014). Changes in phosphorus pill count were not statistically significant (p = 0.88). The egg white diet was well tolerated, and recipe variety appreciated. Pasteurised liquid egg whites may be an effective diet component lowering serum phosphorus without risking malnutrition. Controlled trials are indicated to examine egg white based dietary interventions in MHD patients at home or during haemodialysis treatment. © 2011 European Dialysis and Transplant Nurses Association/European Renal Care Association.

Oxidation of white phosphorus by peroxides in water

NASA Astrophysics Data System (ADS)

Abdreimova, R. R.; Akbaeva, D. N.; Polimbetova, G. S.

2017-10-01

A mixture of hypophosphorous, phosphorous, and phosphoric acids is formed during the anaerobic oxidation of white phosphorus by peroxides [ROOH; R = H, 3-ClC6H4CO, (CH3)3C] in water. The rate of reactions grows considerably upon adding nonpolar organic solvents. The activity series of peroxides and solvents are determined experimentally. NMR spectroscopy shows that the main product of the reaction is phosphorous acid, regardless of the nature of the peroxide and solvent. A radical mechanism of oxidation of white phosphorus by peroxides in water is proposed. It is initiated by the homolysis of peroxide with the formation of HO• radicals that are responsible for the homolytic opening of phosphoric tetrahedrons. Further oxidation and stages of the hydrolysis of intermediate phosphorus-containing compounds yield products of the reaction.

Nocturnal eating disturbs phosphorus excretion in young subjects: a randomized crossover trial.

PubMed

Sakuma, Masae; Noda, Saaya; Morimoto, Yuuka; Suzuki, Akitsu; Nishino, Kanaho; Ando, Sakiko; Umeda, Minako; Ishikawa, Makoto; Arai, Hidekazu

2015-10-08

Nocturnal eating have recently increased. Serum phosphorus levels and regulators of phosphorus have circadian variations, so it is suggested that the timing of eating may be important in controlling serum phosphorus levels. However, there have been no reports on the effects of nocturnal eating on phosphorus metabolism. The objective was to evaluate the effects of nocturnal eating on phosphorus metabolism. Fourteen healthy men participated in two experimental protocols with differing dinner times. The design of this study was a crossover study. The subjects were served test meals three times (breakfast; 07:30 h, lunch; 12:30 h, dinner; 17:30 or 22:30 h) a day. Blood and urine samples were collected to assess diurnal variation until the following morning. The following morning, fasting serum phosphorus levels in the late dinner group were markedly higher than those in the early dinner group (p < 0.001), although serum calcium levels were maintained at approximately constant levels throughout the day in both groups. Fluctuations in urinary calcium excretion were synchronized with the timing of dinner eating, however, fluctuations in urinary phosphorus excretion were not synchronized. Urinary phosphorus excretions at night were inhibited in the late dinner group. In the late dinner group, intact parathyroid hormone levels didn't decrease, and they were significantly higher in this group compared with the early dinner group at 20:00 h (p = 0.004). The following morning, fasting serum fibroblast growth factor 23 levels in the late dinner group had not changed, but those in the early dinner group were significantly increased (p = 0.003). Serum free fatty acid levels before dinner were significantly higher in the late dinner group compared with the early dinner group. Our results indicate that nocturnal eating inhibits phosphorus excretion. It is suggested that nocturnal eating should be abstained from to manage serum phosphorus levels to within an adequate

Removal and retention of phosphorus by periphyton from wastewater with high organic load.

PubMed

Cao, Jinxiang; Hong, Xiaoxing; Pei, Guofeng

2014-01-01

The total phosphorus (TP) removal efficiency from organic wastewater (pig farm and distillery wastewater) were estimated by using filamentous green algae (FGA) and benthic algal mats (BAM) treatment systems under laboratory conditions, and the contents of periphyton phosphorus fractions were determined by using a sequential extraction. The removal rates of TP reached 59-78% within the first 8 days of all treatment systems and could achieve average 80% during 30 day period, and the phosphorus removal rates by using BAM was higher than that of FGA. The ability of retention TP of periphyton enhanced gradually, the BAM TP contents were higher than that of FGA, the highest TP concentrations of BAM and FGA were 26.24 and 10.52 mg P g(-1)·dry weight. Inorganic phosphorus (IP) always exceeded 67.5% of TP, but the organic phosphorus fraction only made up less than 20% of TP. The calcium-binding phosphorus (Ca-P) was the dominant fraction and its relative contribution to TP was more than 40%. The TP was also strongly and positively correlated with the IP and Ca-P (p < 0.01) in periphyton. It showed that the periphyton had a potential ability of rapid phosphorus removing and remarkable retention from wastewater with high load phosphorus.

Phosphorus cycles of forest and upland grassland ecosystems and some effects of land management practices.

PubMed

Harrison, A F

The distribution of phosphorus capital and net annual transfers of phosphorus between the major components of two unfertilized phosphorus-deficient UK ecosystems, an oak--ash woodland in the Lake District and an Agrostis-Festuca grassland in Snowdonia (both on acid brown-earth soils), have been estimted in terms of kg P ha--1. In both ecosystems less than 3% of the phosphorus, totalling 1890 kg P ha--1 and 3040 kg P ha--1 for the woodland and grassland, respectively, is contained in the living biomass and half that is below ground level. Nearly all the phosphorus is in the soil matrix. Although the biomass phosphorus is mostly in the vegetation, the soil fauna and vegetation is slower (25%) than in the grassland vegetatation (208%). More than 85% of the net annual vegetation uptake of phosphorus from the soil is returned to the soil, mainly in organic debris, which in the grassland ecosystem is more than twice as rich in phosphorus (0.125% P) as in the woodland ecosystem (0.053% P). These concentrations are related to the rates of turnover (input/P content) of phosphorus in the litter layer on the soil surface; it is faster in the grassland (460%) than in the woodland (144%). In both cycles plant uptake of phosphorus largely depends on the release of phosphorus through decomposition of the organic matter returned to soil. In both the woodland and the grassland, the amount of cycling phosphorus is potentially reduced by its immobilization in tree and sheep production and in undecomposed organic matter accumulating in soil. It is assumed that the reductions are counterbalanced by the replenishment of cycling phosphorus by (i) some mineralization of organically bound phosphorus in the mineral soil, (ii) the income in rainfall and aerosols not being effectively lost in soil drainage waters and (iii) rock weathering. The effects of the growth of conifers and sheep grazing on the balance between decomposition and accumulation of organic matter returned to soil are

Quantitative evaluation of legacy phosphorus and its spatial distribution.

PubMed

Lou, Hezhen; Zhao, Changsen; Yang, Shengtian; Shi, Liuhua; Wang, Yue; Ren, Xiaoyu; Bai, Juan

2018-04-01

A phosphorus resource crisis threatens the security of global crop production, especially in developing countries like China and Brazil. Legacy phosphorus (legacy-P), which is left behind in agricultural soil by over-fertilization, can help address this issue as a new resource in the soil phosphorus pool. However, issues involved with calculating and defining the spatial distribution of legacy-P hinder its future utilization. To resolve these issues, this study applied remote sensing and ecohydrological modeling to precisely quantify legacy-P and define its spatial distribution in China's Sanjiang Plain from 2000 to 2014. The total legacy-P in the study area was calculated as 579,090 t with an annual average of 38,600 t; this comprises 51.83% of the phosphorus fertilizer applied annually. From 2000 to 2014, the annual amount of legacy-P increased by more than 3.42-fold, equivalent to a 2460-ton increase each year. The spatial distribution of legacy-P showed heterogeneity and agglomeration in this area, with peaks in cultivated land experiencing long-term agricultural development. This study supplies a new approach to finding legacy-P in soil as a precondition for future utilization. Once its spatial distribution is known, legacy-P can be better utilized in agriculture to help alleviate the phosphorus resource crisis. Copyright © 2018 Elsevier Ltd. All rights reserved.

Phosphorus removal characteristics in hydroxyapatite crystallization using converter slag.

PubMed

Kim, Eung-Ho; Hwang, Hwan-Kook; Yim, Soo-Bin

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 removal efficiencies of the batch reactor system were found to increase with increases in the iron and fluoride ion concentrations, and to decrease with increases in the alkalinity and magnesium ion concentration. A column reactor system for HAP crystallization using converter slag was found to achieve high, stable levels of phosphorus elimination: the average PO4-P removal efficiency over 414 days of operation was 90.4%, in which the effluent phosphorus concentration was maintained at less than 0.5 mg/L under the appropriate phosphorus crystallization conditions. The X-ray diffraction (XRD) patterns and Fourier transform infrared (FTIR) spectra of the crystalline material deposited on the seed particles exhibited peaks consistent with HAP. Scanning electron micrograph (SEM) images showed that finely distributed crystalline material was formed on the surfaces of the seed particles. Energy dispersive X-ray spectroscopy (EDS) mapping analysis revealed that the molar Ca/P composition ratio of the crystalline material was 1.72.

Contribution of Food Additives to Sodium and Phosphorus Content of Diets Rich in Processed Foods

PubMed Central

Carrigan, Anna; Klinger, Andrew; Choquette, Suzanne S.; Luzuriaga-McPherson, Alexandra; Bell, Emmy K.; Darnell, Betty; Gutiérrez, Orlando M.

2013-01-01

Objective Phosphorus-based food additives increase total phosphorus content of processed foods. However, the extent to which these additives augment total phosphorus intake per day is unclear. Design, setting, and measurements In order to examine the contribution of phosphorus-based food additives to the total phosphorus content of processed foods, separate four-day menus for a low-additive and additive-enhanced diet were developed using Nutrition Data System for Research (NDSR) software. The low-additive diet was designed to conform to United States Department of Agriculture guidelines for energy and phosphorus intake (~2,000 kcal per day and 900 mg of phosphorus per day) and contained minimally-processed foods. The additive-enhanced diet contained the same food items as the low-additive diet except that highly-processed foods were substituted for minimally-processed foods. Food items from both diets were collected, blended, and sent for measurement of energy and nutrient intake. Results Both the low-additive and additive-enhanced diet provided ~2,200 kcal, 700 mg of calcium and 3,000 mg of potassium per day on average. Measured sodium and phosphorus content standardized per 100 mg of food was higher each day of the additive-enhanced diet as compared to the low-additive. When averaged over the four menu days, measured phosphorus and sodium contents of the additive-enhanced diet were 606 ± 125 and 1,329 ± 642 mg higher than the low-additive diet, respectively, representing a 60% increase in total phosphorus and sodium content on average. When comparing the measured values of the additive-enhanced diet to NDSR-estimated values, there were no statistically significant differences in measured vs. estimated phosphorus contents. Conclusion Phosphorus and sodium additives in processed foods can substantially augment phosphorus and sodium intake, even in relatively healthy diets. Current dietary software may provide reasonable estimates of phosphorus content in

Relationship among Phosphorus Circulation Activity, Bacterial Biomass, pH, and Mineral Concentration in Agricultural Soil.

PubMed

Adhikari, Dinesh; Jiang, Tianyi; Kawagoe, Taiki; Kai, Takamitsu; Kubota, Kenzo; Araki, Kiwako S; Kubo, Motoki

2017-12-04

Improvement of phosphorus circulation in the soil is necessary to enhance phosphorus availability to plants. Phosphorus circulation activity is an index of soil's ability to supply soluble phosphorus from organic phosphorus in the soil solution. To understand the relationship among phosphorus circulation activity; bacterial biomass; pH; and Fe, Al, and Ca concentrations (described as mineral concentration in this paper) in agricultural soil, 232 soil samples from various agricultural fields were collected and analyzed. A weak relationship between phosphorus circulation activity and bacterial biomass was observed in all soil samples ( R ² = 0.25), and this relationship became significantly stronger at near-neutral pH (6.0-7.3; R ² = 0.67). No relationship between phosphorus circulation activity and bacterial biomass was observed at acidic (pH < 6.0) or alkaline (pH > 7.3) pH. A negative correlation between Fe and Al concentrations and phosphorus circulation activity was observed at acidic pH ( R ² = 0.72 and 0.73, respectively), as well as for Ca at alkaline pH ( R ² = 0.64). Therefore, bacterial biomass, pH, and mineral concentration should be considered together for activation of phosphorus circulation activity in the soil. A relationship model was proposed based on the effects of bacterial biomass and mineral concentration on phosphorus circulation activity. The suitable conditions of bacterial biomass, pH, and mineral concentration for phosphorus circulation activity could be estimated from the relationship model.

Overestimation of organic phosphorus in wetland soils by alkaline extraction and molybdate colorimetry.

PubMed

Turner, Benjamin L; Newman, Susan; Reddy, K Ramesh

2006-05-15

Accurate information on the chemical nature of soil phosphorus is essential for understanding its bioavailability and fate in wetland ecosystems. Solution phosphorus-31 nuclear magnetic resonance (31P NMR) spectroscopy was used to assess the conventional colorimetric procedure for phosphorus speciation in alkaline extracts of organic soils from the Florida Everglades. Molybdate colorimetry markedly overestimated organic phosphorus by between 30 and 54% compared to NMR spectroscopy. This was due in large part to the association of inorganic phosphate with organic matter, although the error was exacerbated in some samples by the presence of pyrophosphate, an inorganic polyphosphate that is not detected by colorimetry. The results have important implications for our understanding of phosphorus biogeochemistry in wetlands and suggest that alkaline extraction and solution 31p NMR spectroscopy is the only accurate method for quantifying organic phosphorus in wetland soils.

Examining the proportion of dietary phosphorus from plants, animals and food additives excreted in urine

PubMed Central

St-Jules, David E; Jagannathan, Ram; Gutekunst, Lisa; Kalantar-Zadeh, Kamyar; Sevick, Mary Ann

2016-01-01

Phosphorus bioavailability is an emerging topic of interest in the field of renal nutrition that has important research and clinical implications. Estimates of phosphorus bioavailability, based on digestibility, indicate that bioavailability of phosphorus increases from plants to animals to food additives. In this commentary, we examined the proportion of dietary phosphorus from plants, animals and food additives excreted in urine from four controlled feeding studies conducted in healthy adults and patients with chronic kidney disease. As expected, a smaller proportion of phosphorus from plant foods was excreted in urine compared to animal foods. However, contrary to expectations, phosphorus from food additives appeared to be incompletely absorbed. The apparent discrepancy between digestibility of phosphorus additives and the proportion excreted in urine suggests a need for human balance studies to determine the bioavailability of different sources of phosphorus. PMID:27810171

Phosphorus content in three physical fractions of typical Chernozem

NASA Astrophysics Data System (ADS)

Kotelnikova, Anna; Egorova, Zoya; Sushkov, Nikolai; Matveeva, Natalia; Fastovets, Ilya; Rogova, Olga; Volkov, Dmitriy

2017-04-01

The widespread use of fertilizers makes it necessary to study not only the content but also the forms of occurrence of nutrients in soil, as well as the phase in which nutrients are transferred. These characteristics determine the availability of chemical elements for plants, but remain insufficiently studied. In this work we attempted to gain insight into the distribution of organo-mineral fractions in agriculturally used Chernozem from Voronezh (Russia) and the distribution of phosphorus - one of the most important nutrient elements - in this type of soil. We compared the distributions of phosphorus in physical fractions of the soil in 3 experimental groups: the control group (without fertilizers), the group fertilized with 1 dose of NPK, and the group fertilized with 2 doses of NPK. The soil was sampled during the period of treatment with fertilizers and during the period of aftereffect (4 years after the last application of fertilizers). In order to analyze organo-mineral fractions, we used size-density fractionation to separate the soil samples into three physical fractions: clay-associated fraction with particle size < 1μm (CF), light fraction with particle density < 2.0 g cm-3 (LF), and residual fraction > 2.0 g cm-3 (RF). Total phosphorus content (TPC) in the fractions was determined with Agilent 5100 ICP-AES spectrometer. To compare groups, simultaneous confidence intervals were computed from pooled variance estimators in ANOVA, and Fisher's LSD test was used. We showed that during the period of treatment with fertilizers LF increased proportionally to the dose of fertilizers, and a simultaneous reduction in RF was observed. During the period of aftereffect, the content of these fractions tended to the control value. The increase of LF may indicate increasing availability of nutrients, since this fraction is likely to participate in biological cycles. The analysis of TPC in fractions suggested that during the period of treatment with fertilizers most of

Covalent functionalized black phosphorus quantum dots

NASA Astrophysics Data System (ADS)

Scotognella, Francesco; Kriegel, Ilka; Sassolini, Simone

2018-01-01

Black phosphorus (BP) nanostructures enable a new strategy to tune the electronic and optical properties of this atomically thin material. In this paper we show, via density functional theory calculations, the possibility to modify the optical properties of BP quantum dots via covalent functionalization. The quantum dot selected in this study has chemical formula P24H12 and has been covalent functionalized with one or more benzene rings or anthracene. The effect of functionalization is highlighted in the absorption spectra, where a red shift of the absorption is noticeable. The shift can be ascribed to an electron delocalization in the black phosphorus/organic molecule nanostructure.

Black phosphorus ink formulation for inkjet printing of optoelectronics and photonics.

PubMed

Hu, Guohua; Albrow-Owen, Tom; Jin, Xinxin; Ali, Ayaz; Hu, Yuwei; Howe, Richard C T; Shehzad, Khurram; Yang, Zongyin; Zhu, Xuekun; Woodward, Robert I; Wu, Tien-Chun; Jussila, Henri; Wu, Jiang-Bin; Peng, Peng; Tan, Ping-Heng; Sun, Zhipei; Kelleher, Edmund J R; Zhang, Meng; Xu, Yang; Hasan, Tawfique

2017-08-17

Black phosphorus is a two-dimensional material of great interest, in part because of its high carrier mobility and thickness dependent direct bandgap. However, its instability under ambient conditions limits material deposition options for device fabrication. Here we show a black phosphorus ink that can be reliably inkjet printed, enabling scalable development of optoelectronic and photonic devices. Our binder-free ink suppresses coffee ring formation through induced recirculating Marangoni flow, and supports excellent consistency (< 2% variation) and spatial uniformity (< 3.4% variation), without substrate pre-treatment. Due to rapid ink drying (< 10 s at < 60 °C), printing causes minimal oxidation. Following encapsulation, the printed black phosphorus is stable against long-term (> 30 days) oxidation. We demonstrate printed black phosphorus as a passive switch for ultrafast lasers, stable against intense irradiation, and as a visible to near-infrared photodetector with high responsivities. Our work highlights the promise of this material as a functional ink platform for printed devices.Atomically thin black phosphorus shows promise for optoelectronics and photonics, yet its instability under environmental conditions and the lack of well-established large-area synthesis protocols hinder its applications. Here, the authors demonstrate a stable black phosphorus ink suitable for printed ultrafast lasers and photodetectors.

Mapping watershed potential to contribute phosphorus from geologic materials to receiving streams, southeastern United States

USGS Publications Warehouse

Terziotti, Silvia; Hoos, Anne B.; Harned, Douglas; Garcia, Ana Maria

2010-01-01

As part of the southeastern United States SPARROW (SPAtially Referenced Regressions On Watershed attributes) water-quality model implementation, the U.S. Geological Survey created a dataset to characterize the contribution of phosphorus to streams from weathering and erosion of surficial geologic materials. SPARROW provides estimates of total nitrogen and phosphorus loads in surface waters from point and nonpoint sources. The characterization of the contribution of phosphorus from geologic materials is important to help separate the effects of natural or background sources of phosphorus from anthropogenic sources of phosphorus, such as municipal wastewater or agricultural practices. The potential of a watershed to contribute phosphorus from naturally occurring geologic materials to streams was characterized by using geochemical data from bed-sediment samples collected from first-order streams in relatively undisturbed watersheds as part of the multiyear U.S. Geological Survey National Geochemical Survey. The spatial pattern of bed-sediment phosphorus concentration is offered as a tool to represent the best available information at the regional scale. One issue may weaken the use of bed-sediment phosphorus concentration as a surrogate for the potential for geologic materials in the watershed to contribute to instream levels of phosphorus-an unknown part of the variability in bed-sediment phosphorus concentration may be due to the rates of net deposition and processing of phosphorus in the streambed rather than to variability in the potential of the watershed's geologic materials to contribute phosphorus to the stream. Two additional datasets were created to represent the potential of a watershed to contribute phosphorus from geologic materials disturbed by mining activities from active mines and inactive mines.

Effects of atmospheric reactive phosphorus deposition on phosphorus transport in a subtropical watershed: A Chinese case study.

PubMed

Gao, Yang; Hao, Zhuo; Yang, Tiantian; He, Nianpeng; Wen, Xuefa; Yu, Guirui

2017-07-01

Atmospheric phosphorus (P) deposition is not only an important external macronutrient source for aquatic ecosystems but also a major cause of high export coefficient (EC) values. However, there are limited numbers of studies in the literature that focus on estimating the deposition flux of reactive P (P r ). The aim of this study is to estimate the P r deposition on the Xiangxi River watershed, and therefore, provide a comprehensive understanding about the P r deposition on subtropical watersheds in China. Results have shown that maximal P r deposition fluxes reached 12 kg km -2 in our selected subtropical watershed. Furthermore, we found out the particulate phosphorus (PP) were dominating the total P r deposition in the Xiangxi River watershed. According to our experiments, certain forms of P r deposition were associated with high correlation coefficients with respect to the variation of rainfall intensity. Results also demonstrated that the dissolved organic phosphorus (DOP) and soluble reactive phosphorus (SRP) via wet deposition had large influences on the DOP and SRP concentrations in runoff, while the PO 4 -P and PP via wet deposition only affected PO 4 -P and PP loads through runoff discharge. Our experiments also shown that most parts of the P r in runoff water was derived from rainfall and its magnitudes varied with land types. Results suggested that during the dry season, the P r wet deposition not only was an important source for the P r transport driven by runoff, but also was one of the most important influencing factors that dominated the P r transport in subtropical watersheds. Copyright © 2017 Elsevier Ltd. All rights reserved.

Large magnetoresistance and Hall effect in paramagnetic black phosphorus synthesized from red phosphorus

NASA Astrophysics Data System (ADS)

Jiang, X. H.; Xiong, F.; Zhang, X. W.; Hua, Z. H.; Wang, Z. H.; Yang, S. G.

2018-05-01

Black phosphorus (BP) is an important material, which can be used in the fabrication of phosphorene. In this manuscript, a systematic study was described on the high-pressure synthesis of BP from red phosphorus. For physical characterization, the bulk BP was synthesized under the high pressure of 1.6 GPa and high temperature of 700 °C for 2 h. X-ray diffraction and Raman studies illustrated the formation of high-quality pure phase pleomorphic BP. A nonlinear Hall effect was observed in the BP sample. Magnetoresistance (MR) in the bulk BP reached 90% at 40 K, and positive-to-negative crossover in MR was measured. A paramagnetic feature was found in the prepared bulk BP, and the MR results were attributed to the combination of the effect of classical resistor network and magnetic polaron. The conduction tensors were analyzed by a two-band model to determine the carrier concentration and mobility at several temperatures.

[Soil Phosphorus Forms and Leaching Risk in a Typically Agricultural Catchment of Hefei Suburban].

PubMed

Fan, Hui-hui; Li, Ru-zhong; Pei, Ting-ting; Zhang, Rui-gang

2016-01-15

To investigate the soil phosphorus forms and leaching risk in a typically agricultural catchment of Ershibu River in Hefei Suburban, Chaohu Lake basin, 132 surface soil samples were collected from the catchment area. The spatial distribution of total phosphorus (TP) and bio-available phosphorus (Bio-P), and the spatial variability of soil available phosphorus (Olsen-P) and easy desorption phosphorus (CaCl2-P) were analyzed using the Kriging technology of AreGIS after speciation analysis of soil phosphorus. Moreover, the enrichment level of soil phosphorus was studied, and the phosphorus leaching risk was evaluated through determining the leaching threshold value of soil phosphorus. The results showed that the samples with high contents of TP and Bio-P mainly located in the upstream of the left tributary and on the right side of local area where two tributaries converged. The enrichment rates of soil phosphorus forms were arranged as follows: Ca-P (15.01) > OP (4.16) > TP (3. 42) > IP (2.94) > Ex-P (2.76) > Fe/Al-P (2.43) > Olsen-P (2.34). The critical value of Olsen-P leaching was 18.388 mg x kg(-1), and the leaching samples with values higher than the threshold value accounted for 16.6% of total samples. Generally, the high-risk areas mainly occurred in the upstream of the left tributary, the middle of the right tributary and the local area of the downstream of the area where two tributaries converged.

Steady state phosphorus mass balance model during hemodialysis based on a pseudo one-compartment kinetic model.

PubMed

Leypoldt, John K; Agar, Baris U; Akonur, Alp; Gellens, Mary E; Culleton, Bruce F

2012-11-01

Mathematical models of phosphorus kinetics and mass balance during hemodialysis are in early development. We describe a theoretical phosphorus steady state mass balance model during hemodialysis based on a novel pseudo one-compartment kinetic model. The steady state mass balance model accounted for net intestinal absorption of phosphorus and phosphorus removal by both dialysis and residual kidney function. Analytical mathematical solutions were derived to describe time-dependent intradialytic and interdialytic serum phosphorus concentrations assuming hemodialysis treatments were performed symmetrically throughout a week. Results from the steady state phosphorus mass balance model are described for thrice weekly hemodialysis treatment prescriptions only. The analysis predicts 1) a minimal impact of dialyzer phosphorus clearance on predialysis serum phosphorus concentration using modern, conventional hemodialysis technology, 2) variability in the postdialysis-to-predialysis phosphorus concentration ratio due to differences in patient-specific phosphorus mobilization, and 3) the importance of treatment time in determining the predialysis serum phosphorus concentration. We conclude that a steady state phosphorus mass balance model can be developed based on a pseudo one-compartment kinetic model and that predictions from this model are consistent with previous clinical observations. The predictions from this mass balance model are theoretical and hypothesis-generating only; additional prospective clinical studies will be required for model confirmation.

Reducing sediment and phosphorus in tributary waters with alum and polyacrylamide.

PubMed

Mason, L B; Amrhein, C; Goodson, C C; Matsumoto, M R; Anderson, M A

2005-01-01

The Salton Sea is the largest inland water body in California, covering an area of 980 km(2). Inflow to the Salton Sea (1.6 km(3) yr(-1)) is predominately nutrient-rich agricultural wastewater, which has led to eutrophication. Because internal phosphorus release from the bottom sediments is comparatively low and external phosphorus loading to the Salton Sea is high, reduction of tributary phosphorus is expected to reduce algal blooms, increase dissolved oxygen, and reduce odors. Removing both dissolved phosphorus and phosphorus-laden sediment from agricultural drainage water (ADW) should decrease eutrophication. Both alum and polyacrylamide (PAM) are commonly used in wastewater treatment to remove phosphorus and sediment and were tested for use in tributary waters. Laboratory jar tests determined PAM effectiveness (2 mg L(-1)) for turbidity reduction as cationic > anionic = nonionic. Although cationic PAM was the most effective at reducing turbidity at higher speeds, there was no observed difference between the neutral and anionic PAMs at velocity gradients of 18 to 45 s(-1). Alum (4 mg L(-1) Al) reduced turbidity in low energy systems (velocity gradients < 10 s(-1)) by 95% and was necessary to reduce soluble phosphorus, which comprises 47 to 100% of the total P concentration in the tributaries. When PAM was added with alum, the anionic PAM became ineffective in aiding flocculation. The nonionic PAM (2 mg L(-1)) + alum (4 mg L(-1) Al) is recommended to reduce suspended solids in higher energy systems and reduce soluble P by 93%.

Examining the Proportion of Dietary Phosphorus From Plants, Animals, and Food Additives Excreted in Urine.

PubMed

St-Jules, David E; Jagannathan, Ram; Gutekunst, Lisa; Kalantar-Zadeh, Kamyar; Sevick, Mary Ann

2017-03-01

Phosphorus bioavailability is an emerging topic of interest in the field of renal nutrition that has important research and clinical implications. Estimates of phosphorus bioavailability, based on digestibility, indicate that bioavailability of phosphorus increases from plants to animals to food additives. In this commentary, we examined the proportion of dietary phosphorus from plants, animals, and food additives excreted in urine from four controlled-feeding studies conducted in healthy adults and patients with chronic kidney disease. As expected, a smaller proportion of phosphorus from plant foods was excreted in urine compared to animal foods. However, contrary to expectations, phosphorus from food additives appeared to be incompletely absorbed. The apparent discrepancy between digestibility of phosphorus additives and the proportion excreted in urine suggests a need for human balance studies to determine the bioavailability of different sources of phosphorus. Copyright © 2016 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

46 CFR 151.50-50 - Elemental phosphorus in water.

Code of Federal Regulations, 2012 CFR

2012-10-01

.... (b) When a water displacement method of discharge is used, pressure vessel type cargo tanks, designed... 46 Shipping 5 2012-10-01 2012-10-01 false Elemental phosphorus in water. 151.50-50 Section 151.50... phosphorus in water. (a) Tanks shall be designed and tested for a head equivalent to the design lading of...

Strain-Modulated Bandgap and Piezo-Resistive Effect in Black Phosphorus Field-Effect Transistors

NASA Astrophysics Data System (ADS)

Zhang, Zuocheng; Li, Likai; Horng, Jason; Wang, Nai Zhou; Yang, Fangyuan; Yu, Yijun; Zhang, Yu; Chen, Guorui; Watanabe, Kenji; Taniguchi, Takashi; Chen, Xian Hui; Wang, Feng; Zhang, Yuanbo

2017-10-01

Energy bandgap largely determines the optical and electronic properties of a semiconductor. Variable bandgap therefore makes versatile functionality possible in a single material. In layered material black phosphorus, the bandgap can be modulated by the number of layers; as a result, few-layer black phosphorus has discrete bandgap values that are relevant for opto-electronic applications in the spectral range from red, in monolayer, to mid-infrared in the bulk limit. Here, we further demonstrate continuous bandgap modulation by mechanical strain applied through flexible substrates. The strain-modulated bandgap significantly alters the charge transport in black phosphorus at room temperature; we for the first time observe a large piezo-resistive effect in black phosphorus field-effect transistors (FETs). The effect opens up opportunities for future development of electro-mechanical transducers based on black phosphorus, and we demonstrate strain gauges constructed from black phosphorus thin crystals.

The effects of cosmic particle radiation on pocket mice aboard Apollo XVII: XII. Results of examination of the calvarium, brain, and meninges.

PubMed

Haymaker, W; Zeman, W; Turnbill, C E; Clayton, R K; Bailey, O T; Samorajski, T; Vogel, F S; Lloyd, B; Cruty, M R; Benton, E V; Kraft, L M

1975-04-01

Tissue reactions were found around the monitor (dosimeter) assemblies that had been implanted beneath the scalp of the five pocket mice that flew on Apollo XVII. Mitosis in the dentate gyrus of the hippocampal formation was considerably reduced in comparison with that in control animals. Otherwise the brain tissue as well as the menings in the flight animals appeared unaltered. Since the animals were exposed primarily to high Z-high energy (HZE) cosmic ray particles at the lower end of the high LET spectrum, the lack of changes in the brain cannot be taken as evidence that the brain will suffer no damage from the heavier HZE particles on prolonged manned missions.

Assembly of Ring-Shaped Phosphorus within Carbon Nanotube Nanoreactors.

PubMed

Zhang, Jinying; Zhao, Dan; Xiao, Dingbin; Ma, Chuansheng; Du, Hongchu; Li, Xin; Zhang, Lihui; Huang, Jialiang; Huang, Hongyang; Jia, Chun-Lin; Tománek, David; Niu, Chunming

2017-02-06

A phosphorus allotrope that has not been observed so far, ring-shaped phosphorus consisting of alternate P 8 and P 2 structural units, has been assembled inside multi-walled carbon nanotube nanoreactors with inner diameters of 5-8 nm by a chemical vapor transport and reaction of red phosphorus at 500 °C. The ring-shaped nanostructures with surrounding graphene walls are stable under ambient conditions. The nanostructures were characterized by high-resolution transmission electron microscopy, scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy, Raman scattering, attenuated total reflectance Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Laboratory Studies Of Astrophysically-interesting Phosphorus-bearing Molecules

NASA Astrophysics Data System (ADS)

Ziurys, Lucy M.; Halfen, D. T.; Sun, M.; Clouthier, D. J.

2009-05-01

Over the past year, there has been a renewed interest in the presence of phosphorus-containing molecules in the interstellar medium. Recent observations have increased the number of known interstellar phosphorus-bearing species from two (PN, CP) to six with the identification of HCP, CCP, and PH3 in the carbon-rich circumstellar shell of IRC+10216 and PO in the oxygen-rich envelope of VY Canis Majoris. More species of this type may be present in the ISM, but laboratory rest frequencies, necessary for such detections, are not generally known for many potential molecules. To fill in this gap, we have been conducting measurements of the pure rotational spectra of phosphorus-containing molecules of astrophysical interest, using both millimeter/submm direct absorption and Fourier transform microwave (FTMW) spectroscopy. We have developed a new phosphorus source for this purpose. These methods cover the frequency ranges 65-850 GHz and 4-40 GHz, respectively. Our recent study of the CCP radical (X2Πr) using both of these techniques has resulted in its identification in IRC+10216. Rotational spectra of other molecules such as PCN, HPS, and CH3PH2 have been recorded. We will report on these species and additional new laboratory developments

Phosphorus Concentrations in Stream-Water and Reference Samples - An Assessment of Laboratory Comparability

USGS Publications Warehouse

McHale, Michael R.; McChesney, Dennis

2007-01-01

In 2003, a study was conducted to evaluate the accuracy and precision of 10 laboratories that analyze water-quality samples for phosphorus concentrations in the Catskill Mountain region of New York State. Many environmental studies in this region rely on data from these different laboratories for water-quality analyses, and the data may be used in watershed modeling and management decisions. Therefore, it is important to determine whether the data reported by these laboratories are of comparable accuracy and precision. Each laboratory was sent 12 samples for triplicate analysis for total phosphorus, total dissolved phosphorus, and soluble reactive phosphorus. Eight of these laboratories reported results that met comparability criteria for all samples; the remaining two laboratories met comparability criteria for only about half of the analyses. Neither the analytical method used nor the sample concentration ranges appeared to affect the comparability of results. The laboratories whose results were comparable gave consistently comparable results throughout the concentration range analyzed, and the differences among methods did not diminish comparability. All laboratories had high data precision as indicated by sample triplicate results. In addition, the laboratories consistently reported total phosphorus values greater than total dissolved phosphorus values, and total dissolved phosphorus values greater than soluble reactive phosphorus values, as would be expected. The results of this study emphasize the importance of regular laboratory participation in sample-exchange programs.

Interactions between Microcystis aeruginosa and coexisting amoxicillin contaminant at different phosphorus levels.

PubMed

Liu, Ying; Chen, Shi; Chen, Xiao; Zhang, Jian; Gao, Baoyu

2015-10-30

Microcystis aeruginosa was cultured with 0.05-5 mg L(-1) of phosphorus and exposed to 200-500 ng L(-1) of amoxicillin for seven days. Amoxicillin presented no significant effect (p>0.05) on the growth of M. aeruginosa at phosphorus levels of 0.05 and 0.2 mg L(-1), but stimulated algal growth as a hormesis effect at phosphorus levels of 1 and 5 mg L(-1). Phosphorus and amoxicillin affected the contents of chlorophyll-a, adenosine triphosphate (ATP) and malondialdehyde, the expression of psbA and rbcL, as well as the activities of adenosinetriphosphatase and glutathione S-transferase in similar manners, but regulated the production and release of microcystins and the activities of superoxide dismutase and peroxidase in different ways. Increased photosynthesis activity was related with the ATP consumption for the stress response to amoxicillin, and the stress response was enhanced as the phosphorus concentration increased. The biodegradation of amoxicillin by M. aeruginosa increased from 11.5% to 28.2% as the phosphorus concentration increased. Coexisting amoxicillin aggravated M. aeruginosa pollution by increasing cell density and concentration of microcystins, while M. aeruginosa alleviated amoxicillin pollution via biodegradation. The interactions between M. aeruginosa and amoxicillin were significantly regulated by phosphorus (p<0.05) and led to a complicated situation of combined pollution. Copyright © 2015 Elsevier B.V. All rights reserved.

Phosphorus Loadings to the World's Largest Lakes: Sources and Trends

NASA Astrophysics Data System (ADS)

Fink, Gabriel; Alcamo, Joseph; Flörke, Martina; Reder, Klara

2018-04-01

Eutrophication is a major water quality issue in lakes worldwide and is principally caused by the loadings of phosphorus from catchment areas. It follows that to develop strategies to mitigate eutrophication, we must have a good understanding of the amount, sources, and trends of phosphorus pollution. This paper provides the first consistent and harmonious estimates of current phosphorus loadings to the world's largest 100 lakes, along with the sources of these loadings and their trends. These estimates provide a perspective on the extent of lake eutrophication worldwide, as well as potential input to the evaluation and management of eutrophication in these lakes. We take a modeling approach and apply the WorldQual model for these estimates. The advantage of this approach is that it allows us to fill in large gaps in observational data. From the analysis, we find that about 66 of the 100 lakes are located in developing countries and their catchments have a much larger average phosphorus yield than the lake catchments in developed countries (11.1 versus 0.7 kg TP km-2 year-1). Second, the main source of phosphorus to the examined lakes is inorganic fertilizer (47% of total). Third, between 2005-2010 and 1990-1994, phosphorus pollution increased at 50 out of 100 lakes. Sixty percent of lakes with increasing pollution are in developing countries. P pollution changed primarily due to changing P fertilizer use. In conclusion, we show that the risk of P-stimulated eutrophication is higher in developing countries.

Water Quality, Hydrology, and Simulated Response to Changes in Phosphorus Loading of Butternut Lake, Price and Ashland Counties, Wisconsin, with Special Emphasis on the Effects of Internal Phosphorus Loading in a Polymictic Lake

USGS Publications Warehouse

Robertson, Dale M.; Rose, William J.

2008-01-01

Butternut Lake is a 393-hectare, eutrophic to hypereutrophic lake in northcentral Wisconsin. After only minor improvements in water quality were observed following several actions taken to reduce the nutrient inputs to the lake, a detailed study was conducted from 2002 to 2007 by the U.S. Geological Survey to better understand how the lake functions. The goals of this study were to describe the water quality and hydrology of the lake, quantify external and internal sources of phosphorus, and determine the effects of past and future changes in phosphorus inputs on the water quality of the lake. Since the early 1970s, the water quality of Butternut Lake has changed little in response to nutrient reductions from the watershed. The largest changes were in near-surface total phosphorus concentrations: August concentrations decreased from about 0.09 milligrams per liter (mg/L) to about 0.05 mg/L, but average summer concentrations decreased only from about 0.055-0.060 mg/L to about 0.045 mg/L. Since the early 1970s, only small changes were observed in chlorophyll a concentrations and water clarity (Secchi depths). All major water and phosphorus sources, including the internal release of phosphorus from the sediments (internal loading), were measured directly, and minor sources were estimated to construct detailed water and phosphorus budgets for the lake during monitoring years (MY) 2003 and 2004. During these years, Butternut Creek, Spiller Creek, direct precipitation, small tributaries and near-lake drainage area, and ground water contributed about 62, 20, 8, 7, and 3 percent of the inflow, respectively. The average annual load of phosphorus to the lake was 2,540 kilograms (kg), of which 1,590 kg came from external sources (63 percent) and 945 kg came from the sediments in the lake (37 percent). Of the total external sources, Butternut Creek, Spiller Creek, small tributaries and near-lake drainage area, septic systems, precipitation, and ground water contributed about

Contribution of food additives to sodium and phosphorus content of diets rich in processed foods.

PubMed

Carrigan, Anna; Klinger, Andrew; Choquette, Suzanne S; Luzuriaga-McPherson, Alexandra; Bell, Emmy K; Darnell, Betty; Gutiérrez, Orlando M

2014-01-01

Phosphorus-based food additives increase the total phosphorus content of processed foods. However, the extent to which these additives augment total phosphorus intake per day is unclear. To examine the contribution of phosphorus-based food additives to the total phosphorus content of processed foods, separate 4-day menus for a low-additive and additive-enhanced diet were developed using Nutrition Data System for Research (NDSR) software. The low-additive diet was designed to conform to U.S. Department of Agriculture guidelines for energy and phosphorus intake (∼2,000 kcal/day and 900 mg of phosphorus per day), and it contained minimally processed foods. The additive-enhanced diet contained the same food items as the low-additive diet except that highly processed foods were substituted for minimally processed foods. Food items from both diets were collected, blended, and sent for measurement of energy and nutrient intake. The low-additive and additive-enhanced diet provided approximately 2,200 kcal, 700 mg of calcium, and 3,000 mg of potassium per day on average. Measured sodium and phosphorus content standardized per 100 mg of food was higher each day of the additive-enhanced diet as compared with the low-additive diet. When averaged over the 4 menu days, the measured phosphorus and sodium contents of the additive-enhanced diet were 606 ± 125 and 1,329 ± 642 mg higher than the low-additive diet, respectively, representing a 60% increase in total phosphorus and sodium content on average. When comparing the measured values of the additive-enhanced diet to NDSR-estimated values, there were no statistically significant differences in measured versus estimated phosphorus contents. Phosphorus and sodium additives in processed foods can substantially augment phosphorus and sodium intake, even in relatively healthy diets. Current dietary software may provide reasonable estimates of the phosphorus content in processed foods. Copyright © 2014 National Kidney

Phosphorus sorption on marine carbonate sediment: phosphonate as model organic compounds.

PubMed

Huang, Xiao-Lan; Zhang, Jia-Zhong

2011-11-01

Organophosphonate, characterized by the presence of a stable, covalent, carbon to phosphorus (C-P) bond, is a group of synthetic or biogenic organophosphorus compounds. The fate of these organic phosphorus compounds in the environment is not well studied. This study presents the first investigation on the sorption of phosphorus (P) in the presence of two model phosphonate compounds, 2-aminothylphosphonoic acid (2-AEP) and phosphonoformic acid (PFA), on marine carbonate sediments. In contrast to other organic P compounds, no significant inorganic phosphate exchange was observed in seawater. P was found to adsorb on the sediment only in the presence of PFA, not 2-AEP. This indicated that sorption of P from phosphonate on marine sediment was compound specific. Compared with inorganic phosphate sorption on the same sediments, P sorption from organic phosphorus is much less in the marine environment. Further study is needed to understand the potential role of the organophosphonate compounds in biogeochemical cycle of phosphorus in the environment. Copyright © 2011 Elsevier Ltd. All rights reserved.

Anisotropic in-plane thermal conductivity observed in few-layer black phosphorus

PubMed Central

Luo, Zhe; Maassen, Jesse; Deng, Yexin; Du, Yuchen; Garrelts, Richard P.; Lundstrom, Mark S; Ye, Peide D.; Xu, Xianfan

2015-01-01

Black phosphorus has been revisited recently as a new two-dimensional material showing potential applications in electronics and optoelectronics. Here we report the anisotropic in-plane thermal conductivity of suspended few-layer black phosphorus measured by micro-Raman spectroscopy. The armchair and zigzag thermal conductivities are ∼20 and ∼40 W m−1 K−1 for black phosphorus films thicker than 15 nm, respectively, and decrease to ∼10 and ∼20 W m−1 K−1 as the film thickness is reduced, exhibiting significant anisotropy. The thermal conductivity anisotropic ratio is found to be ∼2 for thick black phosphorus films and drops to ∼1.5 for the thinnest 9.5-nm-thick film. Theoretical modelling reveals that the observed anisotropy is primarily related to the anisotropic phonon dispersion, whereas the intrinsic phonon scattering rates are found to be similar along the armchair and zigzag directions. Surface scattering in the black phosphorus films is shown to strongly suppress the contribution of long mean-free-path acoustic phonons. PMID:26472191

Increasing dietary phosphorus intake from food additives: potential for negative impact on bone health.

PubMed

Takeda, Eiji; Yamamoto, Hironori; Yamanaka-Okumura, Hisami; Taketani, Yutaka

2014-01-01

It is important to consider whether habitual high phosphorus intake adversely affects bone health, because phosphorus intake has been increasing, whereas calcium intake has been decreasing in dietary patterns. A higher total habitual dietary phosphorus intake has been associated with higher serum parathyroid hormone (PTH) and lower serum calcium concentrations in healthy individuals. Higher serum PTH concentrations have been shown in those who consume foods with phosphorus additives. These findings suggest that long-term dietary phosphorus loads and long-term hyperphosphatemia may have important negative effects on bone health. In contrast, PTH concentrations did not increase as a result of high dietary phosphorus intake when phosphorus was provided with adequate amounts of calcium. Intake of foods with a ratio of calcium to phosphorus close to that found in dairy products led to positive effects on bone health. Several randomized controlled trials have shown positive relations between dairy intake and bone mineral density. In our loading test with a low-calcium, high-phosphorus lunch provided to healthy young men, serum PTH concentrations showed peaks at 1 and 6 h, and serum fibroblast growth factor 23 (FGF23) concentrations increased significantly at 8 h after the meal. In contrast, the high-calcium, high-phosphorus meal suppressed the second PTH and FGF23 elevations until 8 h after the meal. This implies that adequate dietary calcium intake is needed to overcome the interfering effects of high phosphorus intake on PTH and FGF23 secretion. FGF23 acts on the parathyroid gland to decrease PTH mRNA and PTH secretion in rats with normal kidney function. However, increased serum FGF23 is an early alteration of mineral metabolism in chronic kidney disease, causing secondary hyperthyroidism, and implying resistance of the parathyroid gland to the action of FGF23 in chronic kidney disease. These findings suggest that long-term high-phosphorus diets may impair bone health

Estimating Legacy Soil Phosphorus Impacts on Phosphorus Loss in The Chesapeake Bay Watershed

USDA-ARS?s Scientific Manuscript database

Agricultural nutrient management is an issue due to phosphorus (P) loss from fields and water quality degradation. This is especially true in watersheds where a history of P application in excess of crop needs has resulted in elevated soil P (legacy P). As practices and policy are implemented in suc...

Competition between Free-Floating Plants Is Strongly Driven by Previously Experienced Phosphorus Concentrations in the Water Column.

PubMed

Peeters, Edwin T H M; Neefjes, Rozemarijn E M; Zuidam, Bastiaan G van

2016-01-01

Nutrients can determine the outcome of the competition between different floating plant species. The response of floating plants to current phosphorus levels may be affected by previously experienced phosphorus concentrations because some species have the ability to store excess phosphorus for later use. This might have an impact on their competition. Here, we investigate the effect of previous and actual phosphorus concentrations on the growth rate of free-floating plant species (Azolla filiculoides, Lemna minor/gibba and Ricciocarpus natans)and the effect of phosphorus history on the competition between L. minor/gibba and A. filiculoides and between L. minor/gibba and R. natans. As expected, plant growth was lower when previously kept at low instead of high phosphorus concentrations. Growth of L. minor/gibba and A. filiculoides with a phosphorus rich history was comparable for low and high actual phosphorus concentrations, however, internal phosphorus concentrations were significantly lower with low actual phosphorus concentration. This indicates that both species perform luxury phosphorus uptake. Furthermore, internal P concentration in Azolla and Lemna increased within two weeks after a period of P deficit without a strong increase in growth. A. filiculoides in a mixture with L. minor/gibba grew faster than its monoculture. Morphological differences may explain why A. filiculoides outcompeted L. minor/gibba and these differences may be induced by phosphorus concentrations in the past. Growth of L. minor/gibba was only reduced by the presence of A. filiculoides with a high phosphorus history. Growth of L. minor/gibba and R. natans in mixtures was positively affected only when they had a high phosphorus history themselves and their competitor a low phosphorus history. These observations clearly indicate that phosphorus history of competing plants is important for understanding the outcome of the competition. Therefore, actual and previously experienced phosphorus

Mathematical Modeling of Nitrous Oxide Production during Denitrifying Phosphorus Removal Process.

PubMed

Liu, Yiwen; Peng, Lai; Chen, Xueming; Ni, Bing-Jie

2015-07-21

A denitrifying phosphorus removal process undergoes frequent alternating anaerobic/anoxic conditions to achieve phosphate release and uptake, during which microbial internal storage polymers (e.g., Polyhydroxyalkanoate (PHA)) could be produced and consumed dynamically. The PHA turnovers play important roles in nitrous oxide (N2O) accumulation during the denitrifying phosphorus removal process. In this work, a mathematical model is developed to describe N2O dynamics and the key role of PHA consumption on N2O accumulation during the denitrifying phosphorus removal process for the first time. In this model, the four-step anoxic storage of polyphosphate and four-step anoxic growth on PHA using nitrate, nitrite, nitric oxide (NO), and N2O consecutively by denitrifying polyphosphate accumulating organisms (DPAOs) are taken into account for describing all potential N2O accumulation steps in the denitrifying phosphorus removal process. The developed model is successfully applied to reproduce experimental data on N2O production obtained from four independent denitrifying phosphorus removal study reports with different experimental conditions. The model satisfactorily describes the N2O accumulation, nitrogen reduction, phosphate release and uptake, and PHA dynamics for all systems, suggesting the validity and applicability of the model. The results indicated a substantial role of PHA consumption in N2O accumulation due to the relatively low N2O reduction rate by using PHA during denitrifying phosphorus removal.

Carbon-hydrogen to carbon-phosphorus transformations.

PubMed

Montchamp, Jean-Luc

2015-01-01

Literature published between 2008 and 2013 concerning the functionalization of carbon-hydrogen into carbon-phosphorus bonds is surveyed. The chapter is organized by reaction mechanism. The majority of methods still proceed via deprotonation of C-H into C-M (M=Li, Na, etc.) followed by reaction with a phosphorus electrophile P-X, where X is usually chlorine. A few examples of electrophilic aromatic substitution and related processes have also been reported, although this approach has not yet been developed significantly. Over the past 5 years a rapidly growing family of reactions includes transition metal "C-H activation" and formally related radical-based processes has been developed. The latter processes offer exciting prospects for the synthesis of organophosphorus compounds.

Phosphorus and groundwater: Establishing links between agricultural use and transport to streams

USGS Publications Warehouse

Domagalski, Joseph L.; Johnson, Henry

2012-01-01

Leaching of applied fertilizer and surface runoff of phosphorus from the soil can contribute to excess growth of algae in downstream water bodies, a condition known as eutrophication. Excessive amounts of algae in eutrophic water bodies can cause large daily changes in the amount of dissolved oxygen in the water because oxygen concentrations tend to be high during daylight hours as a result of photosynthetic activity but then decrease at night. Low concentrations of dissolved oxygen can stress or kill sensitive species living in the water. This study examined concentrations and movement of phosphorus in the soils and groundwater in five agricultural settings across the United States characterized by differences in soil geochemistry, climate, irrigation usage, and cropping systems to assess potential phosphorus movement in the soil and groundwater under common agricultural conditions. The study design included assessment of a variety of agricultural practices, especially cropping patterns and irrigation, so that the factors that contribute to phosphorus movement to groundwater, or sequestration of the phosphorus to soil could be compared and examined. This type of information could potentially be used to formulate best management practices to limit the transport of phosphorus from the agricultural fields.

Bioimpacts of dialyzer variety on phosphorus level in Iranian hemodialysis patients

PubMed Central

Pezeshgi, Aiyoub; Moharrami, Bahareh; Kolifarhood, Goodarz; Sadeghi, Alireza; Asadi-Khiavi, Masoud

2016-01-01

Introduction: Cardiovascular events are the major cause of death in patients with chronic renal failure. About half of dialysis patients because of reduced phosphorus clearance have hyperphosphatemia. Hyperphosphatemia and following secondary hyperparathyroidism lead to some cardiovascular changes. Hemodialysis (HD) partly removes phosphorus during each dialysis session. Objectives: Presented study was designed to evaluate dialyzer variation effect on phosphorus level as a prognostic factor after dialysis using. Materials and Methods: Six kinds of dialyzer were used for dialysis; low flux (LF) dialyzer (F7 and F8), high flux (HF) dialyzer (F70 and F80) and finally hollow-fiber dialyzers including polyethersulfone (PES) 130 HF and polysulfone (PS) 13 LF. Fifty-seven patients were divided into 6 matched groups included three groups of 10 people and 3 groups of 9 persons in groups: A (F70), B (F80), C (F7), D (F8), E (PES 130 HF) and F (PS 13 LF). Patients were treated for one month with these dialyzers. At the end of the month, blood samples were taken again for phosphorus level before dialysis handling. Results: The mean pre-dialysis serum phosphorus was 5.03, 5.4, 5.2, 4.6, 4.95 and 5.1 mg/dl and the mean phosphorus was 5.43, 5.01, 4.9, 4.18, 4.17 and 5.3 mg/dl after one month of dialysis, respectively in groups A to F without any statistically differences between pre- and after one month dialysis values respectively. Discussion: The findings indicate dialyzer type in the control of serum phosphorus has not been effective in the short-term HD. We suggest a study with more duration time. PMID:27471742

Bioimpacts of dialyzer variety on phosphorus level in Iranian hemodialysis patients.

PubMed

Pezeshgi, Aiyoub; Moharrami, Bahareh; Kolifarhood, Goodarz; Sadeghi, Alireza; Asadi-Khiavi, Masoud

2016-01-01

Cardiovascular events are the major cause of death in patients with chronic renal failure. About half of dialysis patients because of reduced phosphorus clearance have hyperphosphatemia. Hyperphosphatemia and following secondary hyperparathyroidism lead to some cardiovascular changes. Hemodialysis (HD) partly removes phosphorus during each dialysis session. Presented study was designed to evaluate dialyzer variation effect on phosphorus level as a prognostic factor after dialysis using. Six kinds of dialyzer were used for dialysis; low flux (LF) dialyzer (F7 and F8), high flux (HF) dialyzer (F70 and F80) and finally hollow-fiber dialyzers including polyethersulfone (PES) 130 HF and polysulfone (PS) 13 LF. Fifty-seven patients were divided into 6 matched groups included three groups of 10 people and 3 groups of 9 persons in groups: A (F70), B (F80), C (F7), D (F8), E (PES 130 HF) and F (PS 13 LF). Patients were treated for one month with these dialyzers. At the end of the month, blood samples were taken again for phosphorus level before dialysis handling. The mean pre-dialysis serum phosphorus was 5.03, 5.4, 5.2, 4.6, 4.95 and 5.1 mg/dl and the mean phosphorus was 5.43, 5.01, 4.9, 4.18, 4.17 and 5.3 mg/dl after one month of dialysis, respectively in groups A to F without any statistically differences between pre- and after one month dialysis values respectively. The findings indicate dialyzer type in the control of serum phosphorus has not been effective in the short-term HD. We suggest a study with more duration time.

Optimization of enhanced biological phosphorus removal after periods of low loading.

PubMed

Miyake, Haruo; Morgenroth, Eberhard

2005-01-01

Enhanced biological phosphorus removal is a well-established technology for the treatment of municipal wastewater. However, increased effluent phosphorus concentrations have been reported after periods (days) of low organic loading. The purpose of this study was to evaluate different operating strategies to prevent discharge of effluent after such low-loading periods. Mechanisms leading to these operational problems have been related to the reduction of polyphosphate-accumulating organisms (PAOs) and their storage compounds (polyhydroxy alkanoates [PHA]). Increased effluent phosphorus concentrations can be the result of an imbalance between influent loading and PAOs in the system and an imbalance between phosphorus release and uptake rates. The following operating conditions were tested in their ability to prevent a reduction of PHA and of overall biomass during low organic loading conditions: (a) unchanged operation, (b) reduced aeration time, (c) reduced sludge wastage, and (d) combination of reduced aeration time and reduced sludge wastage. Experiments were performed in a laboratory-scale anaerobic-aerobic sequencing batch reactor, using acetate as the carbon source. Without operational adjustments, phosphorus-release rates decreased during low-loading periods but recovered rapidly. Phosphorus-uptake rates also decreased, and the recovery typically required several days to increase to normal levels. The combination of reduced aeration time and reduced sludge wastage allowed the maintenance of constant levels of both PHA and overall biomass. A mathematical model was used to explain the influence of the tested operating conditions on PAO and PHA concentrations. While experimental results were in general agreement with model predictions, the kinetic expression for phosphorus uptake deviated significantly for the first 24 hours after low-loading conditions. Mechanisms leading to these deviations need to be further investigated.

Missisquoi Bay Phosphorus Model Addendum

EPA Pesticide Factsheets

This technical memorandum provides results of an extended load reduction simulation. The memorandum serves as an addendum to the main Missisquoi Bay Phosphorus Mass Balance Model report prepared for the Lake Champlain Basin Program by LimnoTech in 2012

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

USDA-ARS?s Scientific Manuscript database

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...

Superconductivity in two-dimensional phosphorus carbide (β0-PC).

PubMed

Wang, Bao-Tian; Liu, Peng-Fei; Bo, Tao; Yin, Wen; Eriksson, Olle; Zhao, Jijun; Wang, Fangwei

2018-05-09

Two-dimensional (2D) boron has been predicted to show superconductivity. However, intrinsic 2D carbon and phosphorus have not been reported to be superconductors, which has inspired us to study the superconductivity of their mixture. Here we performed first-principles calculations for the electronic structure, phonon dispersion, and electron-phonon coupling of the metallic phosphorus carbide monolayer, β0-PC. The results show that it is an intrinsic phonon-mediated superconductor, with an estimated superconducting temperature Tc of ∼13 K. The main contribution to the electron-phonon coupling is from the out-of-plane vibrations of phosphorus. A Kohn anomaly on the first acoustic branch is observed. The superconducting related physical quantities are found to be tunable by applying strain or by carrier doping.

Influence of phosphorus on the tensile stress strain curves in copper

NASA Astrophysics Data System (ADS)

Sandström, Rolf

2016-03-01

Copper canisters are planned to be used for final disposal of spent nuclear fuel in Sweden. The canisters will be exposed to slow plastic straining over extensive periods of time. To be able to predict the mechanical properties a range of basic models have previously been developed for copper with and without phosphorus (Cu-OFP, Cu-OF). Already with the small amount of phosphorus added in the canisters (60 wt. ppm) dramatic improvements in the measured creep strength and the creep ductility are found. The basic models are further developed in the present paper. The influence of phosphorus on slow strain rate tests is analysed. It is shown that the main effect of phosphorus is that it prevents brittle rupture, which is modelled by taking creep cavitation into account.

[Relation between distribution of phosphorus form in the sediment of typical urban shallow lakes and eutrophication].

PubMed

Wang, Chao; Zou, Li-Min; Wang, Pei-Fang; Lin, Zhi-Ping

2008-05-01

The forms of phosphorus in the surface sediments were extracted and determined sequentially with ethylene dinitrilo tetracetic acid (EDTA) technique in three urban shallow lakes: Lake Xuanwu, Lake Mochou and Lake Daming. The results showed that the iron and calcium-bound phosphate, about accounting for 80%, were the main forms of total phosphorus. The contents of iron bound phosphate in Lake Xuanwu and Lake Mochou were higher than that of Lake Daming, reaching 30%-40%. The organic phosphorus existed mainly in the form of alkali extractable phosphorus, while the contents of acid extractable organic phosphorus were low. However, the proportion of acid extractable organic phosphorus to the total phosphorus can indicate the degree of lake eutrophication.

Effects of diet and body size on phosphorus utilization of Liza haematocheila T. & S.

NASA Astrophysics Data System (ADS)

Kang, Bin; Xian, Weiwei; Wu, Yunfei

2008-05-01

A 21-d laboratory experiment was conducted to study, the phosphorus (P) utilization of two different diets by redlip mullet Liza haematocheila T. & S. Sand-filtered water in salinity 30 and temperature 25°C was used. Twenty-nine fish individuals were divided into three groups: 11 to group 1 (G1) fed on diet 1, 11 to group 2 (G2) fed on diet 2, and 7 to contrast group. Diet 1 was a commercial feed, more valuable in nutrition than diet 2 that similar to natural detritus. The results show the intake phosphorus (IP) of G1 was significantly higher than that of G2, and both increased linearly with body size at a certain amount of diet. The retention phosphorus (RP) in fish of G1 was lower than G2. The relationship between retention phosphorus and body size was positive and stronger in G2. Significant difference in faecal phosphorus (FP) was found between G1 and G2. Body size significantly impacted the excretion phosphorus (EP) in G1 but G2. The loss of intake phosphorus in G1 was 10.83-20.27 mg per g fish weight gain, higher than that in G2 for 6.63-9.56. Of the phosphorus, about 10% was allocated into growth, 50% in faeces, and the rest lost in excretion. The main part of phosphorus was lost in faeces but excretion. The phosphorus budget of the fish could be described as 100IP = 7.40RP + 47.39FP + 36.63EP (Diet 1) or 100IP = 11.93RP + 56.64FP + 21.76EP (Diet 2).

Review of Phosphorus Control Measures in the United States and Their Effects on Water Quality

USGS Publications Warehouse

Litke, David W.

1999-01-01

Historical information on phosphorus loadings to the environment and the effect on water quality are summarized in this report, which was produced as part of the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program. Phosphorus is a water-quality constituent of concern because it is often the limiting nutrient responsible for accelerated eutrophication in water bodies. Phosphorus inputs to the environment have increased since 1950 as the use of phosphate fertilizer, manure, and phosphate laundry detergent increased; however, the manufacture of phosphate detergent for household laundry was ended voluntarily in about 1994 after many States had established phosphate detergent bans. Total phosphorus concentrations in raw wastewater effluent contained about 3 milligrams per liter of total phosphorus during the 1940's, increased to about 11 milligrams per liter at the height of phosphate detergent use (1970), and have currently declined to about 5 milligrams per liter. However, in some cases, tertiary wastewater treatment still is needed to effectively improve water quality of streams. Downward trends in phosphorus concentrations since 1970 have been identified in many streams, but median total phosphorus concentrations still exceed the recommended limit of 0.1 milligram per liter across much of the Nation. Data from the NAWQA Program are representative of a variety of phosphorus-control measures, and, therefore, may be used to evaluate the effects of various control strategies. Current areas of concern include: evaluation of the effects of increased manure loadings of phosphorus on soil phosphorus and, subsequently, on ground water and subsurface runoff; determination of point-source and nonpoint-source components of phosphorus loads by geographic modeling and hydrologic separation techniques; and development of methods or indices to evaluate nutrient impairment in streams and rivers to serve as a basis for developing phosphorus criteria or

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.

Inorganic nanotubes and fullerenes . Structure and properties of hypothetical phosphorus fullerenes

NASA Astrophysics Data System (ADS)

Seifert, G.; Heine, T.; Fowler, P. W.

The possibility of stable non-carbon fullerenes is discussed for the case of phosphorus fullerene-like cage structures. On the basis of Density Functional Tight Binding calculations it is shown that many such cages correspond to metastable structures, but with increasing nuclearity become less stable with respect to separate molecular P4 units. Stability rules, known for carbon fullerenes, such as the ``isolated pentagon rule'', do not reflect the different electronic and steric requirements of the phosphorus atom. The computational results tend to rule out phosphorus fullerenes.

Toxicity of acid mine pit lake water remediated with limestone and phosphorus.

PubMed

Neil, Luke L; McCullough, Clint D; Lund, Mark A; Evans, Louis H; Tsvetnenko, Yuri

2009-11-01

Pit lakes are increasingly common worldwide and have potential to provide many benefits. However, lake water toxicity may require remediation before beneficial end uses can be realised. Three treatments to remediate AMD (pH approximately 4.8) pit lake water containing elevated concentrations of Al and Zn from Collie, Western Australia were tested in mesocosms. Treatments were: (a) limestone neutralisation (L), (b) phosphorus amendment (P), and (c) combined limestone neutralisation and phosphorus amendment (L+P). Laboratory bioassays with Ceriodaphnia cf. dubia, Chlorella protothecoides and Tetrahymena thermophila assessed remediation. Limestone neutralisation increased pH and reduced heavy metal concentrations by 98% (Al) to 14% (Mg), removing toxicity to the three test species within 2 months. Phosphorus amendment removed toxicity after 6 months of treatment. However, phosphorus amendment to prior limestone neutralisation failed to reduce toxicity more than limestone neutralisation alone. Low concentrations of both phosphorus and nitrogen appear to limit phytoplankton population growth in all treatments.

Toxicity of acid mine pit lake water remediated with limestone and phosphorus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neil, L.L.; McCullough, C.D.; Lund, M.A.

2009-11-15

Pit lakes are increasingly common worldwide and have potential to provide many benefits. However, lake water toxicity may require remediation before beneficial end uses can be realised. Three treatments to remediate AMD (pH similar to 4.8) pit lake water containing elevated concentrations of Al and Zn from Collie, Western Australia were tested in mesocosms. Treatments were: (a) limestone neutralisation (L), (b) phosphorus amendment (P), and c) combined limestone neutralisation and phosphorus amendment (L+P). Laboratory bioassays with Ceriodaphnia cf. dubia, Chlorella protothecoides and Tetrahymena thermophila assessed remediation. Limestone neutralisation increased pH and reduced heavy metal concentrations by 98% (Al) to 14%more » (Mg), removing toxicity to the three test species within 2 months. Phosphorus amendment removed toxicity after 6 months of treatment. However, phosphorus amendment to prior limestone neutralisation failed to reduce toxicity more than limestone neutralisation alone. Low concentrations of both phosphorus and nitrogen appear to limit phytoplankton population growth in all treatments.« less

A regional modeling framework of phosphorus sources and transport in streams of the southeastern United States

USGS Publications Warehouse

Garcia, Ana Maria.; Hoos, Anne B.; Terziotti, Silvia

2011-01-01

We applied the SPARROW model to estimate phosphorus transport from catchments to stream reaches and subsequent delivery to major receiving water bodies in the Southeastern United States (U.S.). We show that six source variables and five land-to-water transport variables are significant (p < 0.05) in explaining 67% of the variability in long-term log-transformed mean annual phosphorus yields. Three land-to-water variables are a subset of landscape characteristics that have been used as transport factors in phosphorus indices developed by state agencies and are identified through experimental research as influencing land-to-water phosphorus transport at field and plot scales. Two land-to-water variables – soil organic matter and soil pH – are associated with phosphorus sorption, a significant finding given that most state-developed phosphorus indices do not explicitly contain variables for sorption processes. Our findings for Southeastern U.S. streams emphasize the importance of accounting for phosphorus present in the soil profile to predict attainable instream water quality. Regional estimates of phosphorus associated with soil-parent rock were highly significant in explaining instream phosphorus yield variability. Model predictions associate 31% of phosphorus delivered to receiving water bodies to geology and the highest total phosphorus yields in the Southeast were catchments with already high background levels that have been impacted by human activity.

Use of solid phosphorus fractionation data to evaluate phosphorus release from waste activated sludge.

PubMed

Pokhrel, S P; Milke, M W; Bello-Mendoza, R; Buitrón, G; Thiele, J

2018-06-01

Waste activated sludge (WAS) can become an important source of phosphorus (P). P speciation was examined under anaerobic conditions, with different pH (4, 6 and 8) and temperatures (10, 20 and 35 °C). Aqueous P was measured and an extraction protocol was used to find three solid phosphorus fractions. A pH of 4 and a temperature of 35 °C gave a maximum of 51% of total P solubilized in 22 days with 50% of total P solubilized in 7 days. Batch tests indicate that little pH depression is needed to release non-apatite inorganic P (including microbial polyphosphate), while a pH of 4 rather than 6 will release more apatite inorganic P, and that organic P is relatively more difficult to release from WAS. Fractionation analysis of P in WAS can aid in design of more efficient methods for P recovery from WAS. Copyright © 2018 Elsevier Ltd. All rights reserved.

Competition between Free-Floating Plants Is Strongly Driven by Previously Experienced Phosphorus Concentrations in the Water Column

PubMed Central

Peeters, Edwin T. H. M.; Neefjes, Rozemarijn E. M.; van Zuidam, Bastiaan G.

2016-01-01

Nutrients can determine the outcome of the competition between different floating plant species. The response of floating plants to current phosphorus levels may be affected by previously experienced phosphorus concentrations because some species have the ability to store excess phosphorus for later use. This might have an impact on their competition. Here, we investigate the effect of previous and actual phosphorus concentrations on the growth rate of free-floating plant species (Azolla filiculoides, Lemna minor/gibba and Ricciocarpus natans)and the effect of phosphorus history on the competition between L. minor/gibba and A. filiculoides and between L. minor/gibba and R. natans. As expected, plant growth was lower when previously kept at low instead of high phosphorus concentrations. Growth of L. minor/gibba and A. filiculoides with a phosphorus rich history was comparable for low and high actual phosphorus concentrations, however, internal phosphorus concentrations were significantly lower with low actual phosphorus concentration. This indicates that both species perform luxury phosphorus uptake. Furthermore, internal P concentration in Azolla and Lemna increased within two weeks after a period of P deficit without a strong increase in growth. A. filiculoides in a mixture with L. minor/gibba grew faster than its monoculture. Morphological differences may explain why A. filiculoides outcompeted L. minor/gibba and these differences may be induced by phosphorus concentrations in the past. Growth of L. minor/gibba was only reduced by the presence of A. filiculoides with a high phosphorus history. Growth of L. minor/gibba and R. natans in mixtures was positively affected only when they had a high phosphorus history themselves and their competitor a low phosphorus history. These observations clearly indicate that phosphorus history of competing plants is important for understanding the outcome of the competition. Therefore, actual and previously experienced phosphorus

Phosphorus in sediment in the Kent Park Lake watershed, Johnson County, Iowa, 2014–15

USGS Publications Warehouse

Kalkhoff, Stephen J.

2016-07-12

Phosphorus data were collected from the Kent Park Lake watershed in Johnson County, Iowa, in 2014 and 2015 to obtain information to assist in the management of the water quality in the lake. Phosphorus concentrations were measured for sediment from several ponds in the watershed and sediment deposited in the lake. The first set of samples was collected in 2014 to understand phosphorus in several potential sources to the lake and the spatial variability in lake sediments. Phosphorus concentrations ranged from 68 to 380 milligrams per kilogram in lake sediment and from 57 to 220 milligrams per kilogram in sedimentation and dredge spoil ponds. Additional samples were collected in 2015 to determine how phosphorus concentrations vary with depth in the lake sediment. Phosphorus concentrations generally decreased with increasing depth within the lake sediment. In 2015, total phosphorus concentrations in lake sediment ranged from 50 to 340 milligrams per kilogram.

Effect of Polyphosphate-accumulating Organisms on Phosphorus Mobility in Variably Saturated Sand Columns

NASA Astrophysics Data System (ADS)

Stockton, M.; Rojas, C.; Regan, J. M.; Saia, S. M.; Buda, A. R.; Carrick, H. J.; Walter, M. T.

2016-12-01

Excessive application of phosphorus-containing fertilizer along with incomplete knowledge about the factors affecting phosphorus transport and mobility has allowed for a growing number of cases of eutrophication in water bodies. Previous research on enhanced biological phosphorus removal (EBPR) systems used in wastewater treatment plants (WWTPs) has identified polyphosphate-accumulating organisms (PAOs) that are known to accumulate and release phosphorus depending on aerobic/anaerobic conditions. Under anaerobic conditions, intracellular polyphosphate (poly-P) bodies are hydrolyzed releasing phosphate, while under aerobic conditions phosphate is taken up and poly-P inclusions are reformed. The presence of PAOs outside of WWTPs has been shown, but their potential impact on phosphorus mobility in other contexts is not as well known. To study that potential impact, sand columns were subjected to alternating cycles of saturation and unsaturation to mimic variably saturated soils and the resultant anaerobic and aerobic conditions that select for PAOs in a WWTP. Pore water samples collected from sterile control columns and columns inoculated with PAOs from a WWTP were compared during each cycle to monitor changes in dissolved inorganic phosphate and total phosphorus concentrations. In addition, continuous redox data were collected to confirm reducing conditions developed during periods of saturation. Sand particles will be subjected to FISH and DAPI staining to visualize PAOs using probes developed for PAOs in EBPR processes and to determine if changes in intracellular poly-P are detectable between the two cycles in the inoculated columns. Studying the effects of PAOs on phosphorus mobility in these controlled column experiments can contribute to understanding phosphorus retention and release by naturally occurring PAOs in terrestrial system, which ultimately can improve the development of management practices that mitigate phosphorus pollution of water bodies.

Gate induced monolayer behavior in twisted bilayer black phosphorus

NASA Astrophysics Data System (ADS)

Sevik, Cem; Wallbank, John R.; Gülseren, Oğuz; Peeters, François M.; Çakır, Deniz

2017-09-01

Optical and electronic properties of black phosphorus strongly depend on the number of layers and type of stacking. Using first-principles calculations within the framework of density functional theory, we investigate the electronic properties of bilayer black phosphorus with an interlayer twist angle of 90°. These calculations are complemented with a simple k\\centerdot p model which is able to capture most of the low energy features and is valid for arbitrary twist angles. The electronic spectrum of 90° twisted bilayer black phosphorus is found to be x-y isotropic in contrast to the monolayer. However x-y anisotropy, and a partial return to monolayer-like behavior, particularly in the valence band, can be induced by an external out-of-plane electric field. Moreover, the preferred hole effective mass can be rotated by 90° simply by changing the direction of the applied electric field. In particular, a + 0.4 (-0.4) V {{{\\mathringA}}-1} out-of-plane electric field results in a  ˜60% increase in the hole effective mass along the \\mathbf{y} (\\mathbf{x} ) axis and enhances the m\\mathbf{y}\\ast/m\\mathbf{x}\\ast (m\\mathbf{x}\\ast/m\\mathbf{y}\\ast ) ratio as much as by a factor of 40. Our DFT and k\\centerdot p simulations clearly indicate that the twist angle in combination with an appropriate gate voltage is a novel way to tune the electronic and optical properties of bilayer phosphorus and it gives us a new degree of freedom to engineer the properties of black phosphorus based devices.

Edge-of-field evaluation of the Ohio phosphorus risk index

USDA-ARS?s Scientific Manuscript database

The Phosphorus Index (PI) has been the cornerstone for phosphorus (P)-based management and planning over the past twenty years; yet, field-scale evaluation of many state PIs has been limited. In this study, measured P loads in surface runoff and tile discharge from 40 agricultural fields in Ohio wit...

Phosphorus recovery from pig manure solids prior to land application

USDA-ARS?s Scientific Manuscript database

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 ...

The Iron Project & Iron Opacity Project: Updates on Photoionization, Electron-Ion Recombination of Fe XVII and Ca XV

NASA Astrophysics Data System (ADS)

Eissner, W.; Nahar, S.; Pradhan, A.; Hala, H.; Zhao, L.; Bailey, J.

2016-05-01

We have carried out converged close coupling (CCC) calculations for photoionization of Ne-like Fe XVII and demonstrate orders-of-magnitude enhancements in cross section due to successive core excitations. Convergence criteria are: (i) inclusion of sufficient number of residual ion Fe XVIII core states and (ii) high-resolution of myriad autoionizing resonances. We discuss verification of the conventional oscillator strength sum-rule in limited energy regions for bound-free plasma opacity. We will also report preliminary results from a larger R-matrix calculations of photoionization cross sections and electron-ion recombination rates of Ca XV where Rydberg series of resonances are included for core excitations to 28 states of n=2,3 complexes in contrast to previous 7 states of n=2 complex. The new results show existence of high-peak resonances of n=3 complex and enhanced background in high energy photoionization and a corresponding enhancement in the recombination in the high temperature region. Partial support: NSF, DOE, Ohio Supercomputer Center.

p-type doping by platinum diffusion in low phosphorus doped silicon

NASA Astrophysics Data System (ADS)

Ventura, L.; Pichaud, B.; Vervisch, W.; Lanois, F.

2003-07-01

In this work we show that the cooling rate following a platinum diffusion strongly influences the electrical conductivity in weakly phosphorus doped silicon. Diffusions were performed at the temperature of 910 °C in the range of 8 32 hours in 0.6, 30, and 60 Ωrm cm phosphorus doped silicon samples. Spreading resistance profile analyses clearly show an n-type to p-type conversion under the surface when samples are cooled slowly. On the other hand, a compensation of the phosphorus donors can only be observed when samples are quenched. One Pt related acceptor deep level at 0.43 eV from the valence band is assumed to be at the origin of the type conversion mechanism. Its concentration increases by lowering the applied cooling rate. A complex formation with fast species such as interstitial Pt atoms or intrinsic point defects is expected. In 0.6 Ωrm cm phosphorus doped silicon, no acceptor deep level in the lower band gap is detected by DLTS measurement. This removes the opportunity of a pairing between phosphorus and platinum and suggests the possibility of a Fermi level controlled complex formation.

Effects of ZnO nanoparticles on wastewater biological nitrogen and phosphorus removal.

PubMed

Zheng, Xiong; Wu, Rui; Chen, Yinguang

2011-04-01

With the increasing utilization of nanomaterials, zinc oxide nanoparticles (ZnO NPs) have been reported to induce adverse effects on human health and aquatic organisms. However, the potential impacts of ZnO NPs on wastewater nitrogen and phosphorus removal with an activated sludge process are unknown. In this paper, short-term exposure experiments were conducted to determine whether ZnO NPs caused adverse impacts on biological nitrogen and phosphorus removal in the unacclimated anaerobic-low dissolved oxygen sequencing batch reactor. Compared with the absence of ZnO NPs, the presence of 10 and 50 mg/L of ZnO NPs decreased total nitrogen removal efficiencies from 81.5% to 75.6% and 70.8%, respectively. The corresponding effluent phosphorus concentrations increased from nondetectable to 10.3 and 16.5 mg/L, respectively, which were higher than the influent phosphorus (9.8 mg/L), suggesting that higher concentration of ZnO NPs induced the loss of normal phosphorus removal. It was found that the inhibition of nitrogen and phosphorus removal induced by higher concentrations of ZnO NPs was due to the release of zinc ions from ZnO NPs dissolution and increase of reactive oxygen species (ROS) production, which caused inhibitory effect on polyphosphate-accumulating organisms and decreased nitrate reductase, exopolyphosphatase, and polyphosphate kinase activities.

Penguins significantly increased phosphine formation and phosphorus contribution in maritime Antarctic soils.

PubMed

Zhu, Renbin; Wang, Qing; Ding, Wei; Wang, Can; Hou, Lijun; Ma, Dawei

2014-11-14

Most studies on phosphorus cycle in the natural environment focused on phosphates, with limited data available for the reduced phosphine (PH3). In this paper, matrix-bound phosphine (MBP), gaseous phosphine fluxes and phosphorus fractions in the soils were investigated from a penguin colony, a seal colony and the adjacent animal-lacking tundra and background sites. The MBP levels (mean 200.3 ng kg(-1)) in penguin colony soils were much higher than those in seal colony soils, animal-lacking tundra soils and the background soils. Field PH3 flux observation and laboratory incubation experiments confirmed that penguin colony soils produced much higher PH3 emissions than seal colony soils and animal-lacking tundra soils. Overall high MBP levels and PH3 emissions were modulated by soil biogeochemical processes associated with penguin activities: sufficient supply of the nutrients phosphorus, nitrogen, and organic carbon from penguin guano, high soil bacterial abundance and phosphatase activity. It was proposed that organic or inorganic phosphorus compounds from penguin guano or seal excreta could be reduced to PH3 in the Antarctic soils through the bacterial activity. Our results indicated that penguin activity significantly increased soil phosphine formation and phosphorus contribution, thus played an important role in phosphorus cycle in terrestrial ecosystems of maritime Antarctica.

Penguins significantly increased phosphine formation and phosphorus contribution in maritime Antarctic soils

PubMed Central

Zhu, Renbin; Wang, Qing; Ding, Wei; Wang, Can; Hou, Lijun; Ma, Dawei

2014-01-01

Most studies on phosphorus cycle in the natural environment focused on phosphates, with limited data available for the reduced phosphine (PH3). In this paper, matrix-bound phosphine (MBP), gaseous phosphine fluxes and phosphorus fractions in the soils were investigated from a penguin colony, a seal colony and the adjacent animal-lacking tundra and background sites. The MBP levels (mean 200.3 ng kg−1) in penguin colony soils were much higher than those in seal colony soils, animal-lacking tundra soils and the background soils. Field PH3 flux observation and laboratory incubation experiments confirmed that penguin colony soils produced much higher PH3 emissions than seal colony soils and animal-lacking tundra soils. Overall high MBP levels and PH3 emissions were modulated by soil biogeochemical processes associated with penguin activities: sufficient supply of the nutrients phosphorus, nitrogen, and organic carbon from penguin guano, high soil bacterial abundance and phosphatase activity. It was proposed that organic or inorganic phosphorus compounds from penguin guano or seal excreta could be reduced to PH3 in the Antarctic soils through the bacterial activity. Our results indicated that penguin activity significantly increased soil phosphine formation and phosphorus contribution, thus played an important role in phosphorus cycle in terrestrial ecosystems of maritime Antarctica. PMID:25394572

Encapsulation and Polymerization of White Phosphorus Inside Single-Wall Carbon Nanotubes.

PubMed

Hart, Martin; White, Edward R; Chen, Ji; McGilvery, Catriona M; Pickard, Chris J; Michaelides, Angelos; Sella, Andrea; Shaffer, Milo S P; Salzmann, Christoph G

2017-07-03

Elemental phosphorus displays an impressive number of allotropes with highly diverse chemical and physical properties. White phosphorus has now been filled into single-wall carbon nanotubes (SWCNTs) from the liquid and thereby stabilized against the highly exothermic reaction with atmospheric oxygen. The encapsulated tetraphosphorus molecules were visualized with transmission electron microscopy, but found to convert readily into chain structures inside the SWCNT "nanoreactors". The energies of the possible chain structures were determined computationally, highlighting a delicate balance between the extent of polymerization and the SWCNT diameter. Experimentally, a single-stranded zig-zag chain of phosphorus atoms was observed, which is the lowest energy structure at small confinement diameters. These one-dimensional chains provide a glimpse into the very first steps of the transformation from white to red phosphorus. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Trends in phosphorus loading to the western basin of Lake ...

EPA Pesticide Factsheets

Dave Dolan spent much of his career computing and compiling phosphorus loads to the Great Lakes. None of his work in this area has been more valuable than his continued load estimates to Lake Erie, which has allowed us to unambiguously interpret the cyanobacteria blooms and hypoxia development in the lake. To help understand the re-occurrence of cyanobacteria blooms in the Western Basin of Lake Erie, we have examined the phosphorus loading to the Western Basin over the past 15 years. Furthermore, we have examined the relative contributions from various tributaries and the Detroit River. On an annual basis the total phosphorus load has not exhibited a trend, other than being well correlated with flow from major tributaries. However, the dissolved reactive phosphorus (DRP) load has trended upward, returning to levels observed in the mid-1970s. This increase has largely been attributed to the increase in flow-weighted DRP concentration in the Maumee River. Over the period, about half of the phosphorus load comes from the Maumee River with the other half coming from the Detroit River; other tributaries contribute much small amounts to the load. Seasonal analysis shows the highest percentage of the load occurs in the spring during high flow events. We are very grateful to our friend Dave for making this type of analysis possible not applicable

Review on the preparation and modified technologies of microencapsulated red phosphorus

NASA Astrophysics Data System (ADS)

Cheng, Chen; Du, Shiguo; Yan, Jun

2017-10-01

Coated by a compact shell structure, pristine red phosphorus transforms into microcapsule red phosphorus (MCRP) with lower PH3 emission and improved compatibility with polymer matrix. Diverse kinds of microcapsule red phosphorus are classified by shell material, i.e.organic shell material MCRP, inorganic shell material MCRP and composite shell material MCRP. Furthermore, the modified technology to make up deficiencies of MCRP is also introduced in the lecture. Aiming at the existing microencapsulation craft, a more harmless and high-efficiency process should be presented, and ultrafine MCRP is also urgent to be prepared.

Total Phosphorus Loads for Selected Tributaries to Sebago Lake, Maine

USGS Publications Warehouse

Hodgkins, Glenn A.

2001-01-01

The streamflow and water-quality datacollection networks of the Portland Water District (PWD) and the U.S. Geological Survey (USGS) as of February 2000 were analyzed in terms of their applicability for estimating total phosphorus loads for selected tributaries to Sebago Lake in southern Maine. The long-term unit-area mean annual flows for the Songo River and for small, ungaged tributaries are similar to the long-term unit-area mean annual flows for the Crooked River and other gaged tributaries to Sebago Lake, based on a regression equation that estimates mean annual streamflows in Maine. Unit-area peak streamflows of Sebago Lake tributaries can be quite different, based on a regression equation that estimates peak streamflows for Maine. Crooked River had a statistically significant positive relation (Kendall's Tau test, p=0.0004) between streamflow and total phosphorus concentration. Panther Run had a statistically significant negative relation (p=0.0015). Significant positive relations may indicate contributions from nonpoint sources or sediment resuspension, whereas significant negative relations may indicate dilution of point sources. Total phosphorus concentrations were significantly larger in the Crooked River than in the Songo River (Wilcoxon rank-sum test, p<0.0001). Evidence was insufficient, however, to indicate that phosphorus concentrations from medium-sized drainage basins, at a significance level of 0.05, were different from each other or that concentrations in small-sized drainage basins were different from each other (Kruskal-Wallis test, p= 0.0980, 0.1265). All large- and medium-sized drainage basins were sampled for total phosphorus approximately monthly. Although not all small drainage basins were sampled, they may be well represented by the small drainage basins that were sampled. If the tributaries gaged by PWD had adequate streamflow data, the current PWD tributary monitoring program would probably produce total phosphorus loading data that

Phosphorus Concentrations, Loads, and Yields in the Illinois River Basin, Arkansas and Oklahoma, 1997-2001

USGS Publications Warehouse

Pickup, Barbara E.; Andrews, William J.; Haggard, Brian E.; Green, W. Reed

2003-01-01

The Illinois River and tributaries, Flint Creek and the Baron Fork, are designated scenic rivers in Oklahoma. Recent phosphorus increases in streams in the basin have resulted in the growth of excess algae, which have limited the aesthetic benefits of water bodies in the basin, especially the Illinois River and Lake Tenkiller. The Oklahoma Water Resources Board has established a standard for total phosphorus not to exceed the 30- day geometric mean concentration of 0.037 milligram per liter in Oklahoma Scenic Rivers. Data from water-quality samples from 1997 to 2001 were used to summarize phosphorus concentrations and estimate phosphorus loads, yields, and flowweighted concentrations in the Illinois River basin. Phosphorus concentrations in the Illinois River basin generally were significantly greater in runoff-event samples than in base-flow samples. Phosphorus concentrations generally decreased with increasing base flow, from dilution, and increased with runoff, possibly because of phosphorus resuspension, stream bank erosion, and the addition of phosphorus from nonpoint sources. Estimated mean annual phosphorus loads were greater at the Illinois River stations than at Flint Creek and the Baron Fork. Loads appeared to generally increase with time during 1997-2001 at all stations, but this increase might be partly attributable to the beginning of runoff-event sampling in the basin in July 1999. Base-flow loads at stations on the Illinois River were about 10 times greater than those on the Baron Fork and 5 times greater than those on Flint Creek. Runoff components of the annual total phosphorus load ranged from 58.7 to 96.8 percent from 1997-2001. Base-flow and runoff loads were generally greatest in spring (March through May) or summer (June through August), and were least in fall (September through November). Total yields of phosphorus ranged from 107 to 797 pounds per year per square mile. Greatest yields were at Flint Creek near Kansas (365 to 797 pounds per

A Regional Modeling Framework of Phosphorus Sources and Transport in Streams of the Southeastern United States

USGS Publications Warehouse

Garcia, A.M.; Hoos, A.B.; Terziotti, S.

2011-01-01

We applied the SPARROW model to estimate phosphorus transport from catchments to stream reaches and subsequent delivery to major receiving water bodies in the Southeastern United States (U.S.). We show that six source variables and five land-to-water transport variables are significant (p<0.05) in explaining 67% of the variability in long-term log-transformed mean annual phosphorus yields. Three land-to-water variables are a subset of landscape characteristics that have been used as transport factors in phosphorus indices developed by state agencies and are identified through experimental research as influencing land-to-water phosphorus transport at field and plot scales. Two land-to-water variables - soil organic matter and soil pH - are associated with phosphorus sorption, a significant finding given that most state-developed phosphorus indices do not explicitly contain variables for sorption processes. Our findings for Southeastern U.S. streams emphasize the importance of accounting for phosphorus present in the soil profile to predict attainable instream water quality. Regional estimates of phosphorus associated with soil-parent rock were highly significant in explaining instream phosphorus yield variability. Model predictions associate 31% of phosphorus delivered to receiving water bodies to geology and the highest total phosphorus yields in the Southeast were catchments with already high background levels that have been impacted by human activity. ?? 2011 American Water Resources Association. This article is a US Government work and is in the public domain in the USA.

Biochar as phosphorus transporter to support the closure of the phosphorus cycle

NASA Astrophysics Data System (ADS)

Soja, Gerhard; Jagerhofer, Reinhard; Fristak, Vladimir; Pfeifer, Christoph

2017-04-01

Waste materials rich in phosphorus could partly substitute rock phosphate-based mineral fertilizers. As rock phosphate is listed as critical raw material, measures for increasing the recovery rate of phosphorus and for closing the phosphorus cycle are required. However, direct use of the waste materials as fertilizers are frequently not possible because of legal constraints, adverse side effects because of co-occurring contaminants or hygienic concerns. So this study had the objective to test the appropriateness of carbonizing P-rich residues that can be used as secondary P resources for producing P fertilizers. The resulting biochar or hydrochar products should be tested for the bioavailability of P for plant uptake. Feedstock materials tested as secondary P resources were chicken manure, animal bone flour, sewage sludge, and digestates. These materials were either pyrolyzed at different temperatures, partly with different chemical modifications, or hydrothermally carbonized. The biochar and hydrochar products were analyzed for their total and available P concentrations, and the plant bioavailability was determined with a standardized plant growth test with rye (Neubauer-test). The results showed that biochar produced from a mixture of chicken manure and saw dust was equivalent to a standard phosphate fertilizer (superphosphate) with respect to P available for plant uptake. For most materials, a pyrolysis temperature of 400 °C was slightly more beneficial for P availability than 500 °C. Pyrolytic carbonization mostly was more supportive for plant growth than hydrothermal carbonization of the tested feedstocks. For some feedstocks the addition of sodium carbonate improved the P uptake of the plants without affecting the biomass production. The results show that P-rich waste materials used as secondary resources for carbonization can effectively contribute to increased P recovery, savings in the use of mineral phosphate fertilizers and reduced P loads to non

Phosphorus mobility among sediments, water and cyanobacteria enhanced by cyanobacteria blooms in eutrophic Lake Dianchi.

PubMed

Cao, Xin; Wang, Yiqi; He, Jian; Luo, Xingzhang; Zheng, Zheng

2016-12-01

This study was focused on the phosphorus mobility among sediments, water and cyanobacteria in eutrophic Lake Dianchi. Four conditions lake water, water and algae, water and sediments, and three objects together were conducted to investigate the effects of cyanobacteria growth on the migration and transformation of phosphorus. Results showed a persistent correlation between the development of cyanobacterial blooms and the increase of soluble reactive phosphorus (SRP) in the lake water under the condition of three objects together. Time-course assays measuring different forms of phosphorus in sediments indicated that inorganic phosphorus (IP) and NaOH-P were relatively more easier to migrate out of sediment to the water and cyanobacteria. Further studies on phosphorus mobility showed that up to 70.2% of the released phosphorus could be absorbed by cyanobacteria, indicating that sediment is a major source of phosphorus when external loading is reduced. Time-course assays also showed that the development of cyanobacterial blooms promoted an increase in pH and a decrease in the redox potential of the lake water. The structure of the microbial communities in sediments was also significantly changed, revealed a great impaction of cyanobacterial blooms on the microbial communities in sediments, which may contribute to phosphorus release. Our study simulated the cyanobacterial blooms of Lake Dianchi and revealed that the cyanobacterial blooms is a driving force for phosphorus mobility among sediments, water and cyanobacteria. The outbreak of algal blooms caused deterioration in water quality. The P in the sediments represented a significant supply for the growth of cyanobacteria. Copyright © 2016 Elsevier Ltd. All rights reserved.

Nitrogen and phosphorus removed from a subsurface flow multi-stage filtration system purifying agricultural runoff.

PubMed

Zhao, Yaqi; Huang, Lei; Chen, Yucheng

2018-07-01

Agricultural nonpoint source pollution has been increasingly serious in China since the 1990s. The main causes were excessive inputs of nitrogen fertilizer and pesticides. A multi-stage filtration system was built to test the purification efficiencies and removal characteristics of nitrogen and phosphorus when treating agricultural runoff. Simulated runoff pollution was prepared by using river water as source water based on the monitoring of local agricultural runoff. Experimental study had been performed from September to November 2013, adopting 12 h for flooding and 12 h for drying. The results showed that the system was made adaptive to variation of inflow quality and quantity, and had good removal for dissolved total nitrogen, total nitrogen, dissolved total phosphorus (DTP), and total phosphorus, and the average removal rate was 27%, 36%, 32%, and 48%, respectively. Except nitrate ([Formula: see text]), other forms of nitrogen and phosphorus all decreased with the increase of stages. Nitrogen was removed mainly in particle form the first stage, and mostly removed in dissolved form the second and third stage. Phosphorus was removed mainly in particulate during the first two stages, but the removal of particulate phosphorus and DTP were almost the same in the last stage. An approximate logarithmic relationship between removal loading and influent loading to nitrogen and phosphorus was noted in the experimental system, and the correlation coefficient was 0.78-0.94. [Formula: see text]: ammonium; [Formula: see text]: nitrite; [Formula: see text]: nitrate; DTN: dissolved total nitrogen; TN: total nitrogen; DTP: dissolved total phosphorus; TP: total phosphorus; PN: particulate nitrogen; PP: particulate phosphorus.

Changes in total phosphorus concentration in the Red River of the North Basin, 1970-2012

USGS Publications Warehouse

Ryberg, Karen R.; Akyüz, F. Adnan; Lin, Wei

2015-01-01

The Red River of the North drains much of eastern North Dakota and northwestern Minnesota and flows north into Manitoba, Canada, ultimately into Lake Winnipeg; therefore, water quality is an International concern. With increased runoff in the past few decades, phosphorus flux (the amount of phosphorus transported by the river) has increased. This is a concern, especially with respect to Lake Winnipeg, an important inland fishery and recreational destination. There is pressure at the State and International levels to reduce phosphorus flux, an expensive proposition. Depending on the method (controlling sources, settling ponds, buffer strips), control of phosphorus flux is not always effective during spring runoff. This work represents a first step in developing a causal model for phosphorus flux by examining available data and changes in concentration over time. Total phosphorus concentration data for the Red River at Emerson, Manitoba, and at Fargo, North Dakota-Moorhead, Minnesota, were summarized and then analyzed using WRTDS (Weighted Regressions on Time, Discharge, and Season) to describe total phosphorus changes over time in two analysis periods: 1970-1993 and 1993-2012. Total phosphorus concentration increased in the first period at Emerson, Manitoba, indicating phosphorus was likely being transported to streams during runoff events. A very different pattern occurred at Fargo-Moorhead with declines in concentration, except at high discharge. While concentration continually changes, during the second period it decreased during spring runoff at Emerson and Fargo-Moorhead and during the growing season at Fargo-Moorhead, perhaps because of improved agricultural practices and declines in some uses of phosphorus.

Anticancer copper(II) phosphorus dendrimers are potent proapoptotic Bax activators.

PubMed

Mignani, Serge; El Brahmi, Nabil; Eloy, Laure; Poupon, Joel; Nicolas, Valérie; Steinmetz, Anke; El Kazzouli, Said; Bousmina, Mosto M; Blanchard-Desce, Mireille; Caminade, Anne-Marie; Majoral, Jean-Pierre; Cresteil, Thierry

2017-05-26

A multivalent phosphorus dendrimer 1G 3 and its corresponding Cu-complex, 1G 3 -Cu have been recently identified as agents retaining high antiproliferative potency. This antiproliferative capacity was preserved in cell lines overexpressing the efflux pump ABC B1, whereas cross-resistance was observed in ovarian cancer cell lines resistant to cisplatin. Theoretical 3D models were constructed: the dendrimers appear as irregularly shaped disk-like nano-objects of about 22 Å thickness and 49 Å diameter, which accumulated in cells after penetration by endocytosis. To get insight in their mode of action, cell death pathways have been examined in human cancer cell lines: early apoptosis was followed by secondary necrosis after multivalent phosphorus dendrimers exposure. The multivalent plain phosphorus dendrimer 1G 3 moderately activated caspase-3 activity, in contrast with the multivalent Cu-conjugated phosphorus dendrimer 1G 3 -Cu which strikingly reduced the caspase-3 content and activity. This decrease of caspase activity is not related to the presence of copper, since inorganic copper has no or little effect on caspase-3. Conversely the potent apoptosis activation could be related to a noticeable translocation of Bax to the mitochondria, resulting in the release of AIF into the cytosol, its translocation to the nucleus and a severe DNA fragmentation, without alteration of the cell cycle. The multivalent Cu-conjugated phosphorus dendrimer is more efficient than its non-complexed analog to activate this pathway in close relationship with the higher antiproliferative potency. Therefore, this multivalent Cu-conjugated phosphorus dendrimer 1G 3 -Cu can be considered as a new and promising first-in-class antiproliferative agent with a distinctive mode of action, inducing apoptosis tumor cell death through Bax activation pathway. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Usefulness of Mehlich-3 test in the monitoring of phosphorus dispersion from Polish arable soils.

PubMed

Szara, Ewa; Sosulski, Tomasz; Szymańska, Magdalena; Szyszkowska, Katarzyna

2018-04-19

A considerable area of soils with low abundance of plant-available phosphorus and relatively low consumption of phosphorus fertilisers recorded in Poland over the last 20-25 years suggests that the dispersion of phosphates from arable soils in Poland can be low. The literature, however, provides reports on a considerable share of Polish agriculture in phosphorus pollution of Baltic Sea waters. The literature provides no data concerning phosphorus sorption parameters of arable soils in Poland. Due to this, the study involved the analysis of sorption properties: 1-point phosphorus sorption index (PSI) and degree of phosphorus saturation, based on molar ratio P, Al, and Fe determined by the Mehlich-3 method (DPS-1 M3  = P / (Al + Fe) and DPS-2 M3  = P / Al), 59 soils representing the main types of texture of soils in Poland, characterised by variable content of plant-available phosphorus by Egner-Riehm DL, organic carbon, and soil pH. The obtained results suggest that the soil texture has a lower effect on sorption properties (PSI) than the degree of acidification. Sorption parameters of soils increased with soil acidification as a result of an increase in the content of Al and Fe extracted by the Mehlich-3 extract in strongly acidified soils. An important finding of our study was evidencing that within the same class of abundance in plant-available phosphorus, the soils varied in the degree of phosphorus saturation and content of active phosphorus. This suggests the possibility of losses of phosphorus even from soils with low abundance of the component provided they are characterised by a high value of parameters DPS-1 M3 and DPS-2 M3 .

Prevalence of Phosphorus-Based Additives in the Australian Food Supply: A Challenge for Dietary Education?

PubMed

McCutcheon, Jemma; Campbell, Katrina; Ferguson, Maree; Day, Sarah; Rossi, Megan

2015-09-01

Phosphorus-based food additives may pose a significant risk in chronic kidney disease given the link between hyperphosphatemia and cardiovascular disease. The objective of the study was to determine the prevalence of phosphorus-based food additives in best-selling processed grocery products and to establish how they were reported on food labels. A data set of 3000 best-selling grocery items in Australia across 15 food and beverage categories was obtained for the 12 months ending December 2013 produced by the Nielsen Company's Homescan database. The nutrition labels of the products were reviewed in store for phosphorus additives. The type of additive, total number of additives, and method of reporting (written out in words or as an E number) were recorded. Presence of phosphorus-based food additives, number of phosphorus-based food additives per product, and the reporting method of additives on product ingredient lists. Phosphorus-based additives were identified in 44% of food and beverages reviewed. Additives were particularly common in the categories of small goods (96%), bakery goods (93%), frozen meals (75%), prepared foods (70%), and biscuits (65%). A total of 19 different phosphorus additives were identified across the reviewed products. From the items containing phosphorus additives, there was a median (minimum-maximum) of 2 (1-7) additives per product. Additives by E number (81%) was the most common method of reporting. Phosphorus-based food additives are common in the Australian food supply. This suggests that prioritizing phosphorus additive education may be an important strategy in the dietary management of hyperphosphatemia. Further research to establish a database of food items containing phosphorus-based additives is warranted. Copyright © 2015 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Phosphorus Control in DRI-EAF Steelmaking: Thermodynamics, Effect of Alumina, and Process Modeling

NASA Astrophysics Data System (ADS)

Tayeb, Mohammed A.

Flexibility in raw materials, the lower natural gas prices, and the increased use of nonconventional Electric Arc Furnace (EAF) steelmaking using up to 100% Direct Reduced Iron (DRI) have prompted a renewed interest in better control of phosphorus. Iron ore and DRI have higher phosphorus and silica compared to scrap. Although significant work has been done on understanding the partitioning of phosphorus between slag and metal for slags with chemistries relevant to those used in the Basic Oxygen Furnace (BOF), there is little reported work on slag chemistries corresponding to that in the EAF when DRI is used (EAF-DRI). In the current research, phosphorus equilibria between molten Fe-P alloys and CaO-SiO2-Al2O3-P 2O5-FeO-MgOsaturated slag system were investigated. An equilibrium correlation for phosphorus partition as a function of slag composition and temperature has been developed and resulted in better predictions compared with those proposed by earlier workers. As well, it is suitable for both BOF and EAF slags and includes coefficients for silica and alumina, unlike previous correlations. Low amounts of Al2O3 are present in EAF and BOF slags, but no appreciable work has been carried out to study the effect of alumina on the phosphorus partition. When DRI is used, the Al2O 3 contents can also be much higher. The data from this work indicates that there is significant reduction in Lp as the alumina fraction in the slag increases. The observed effect of alumina is attributed to its acidity, which contributes to the reduction of the phosphorus capacity of the slag by lowering the activities of iron oxide and calcium oxide. This in turn lowers the activity of oxygen and oxygen ions needed for phosphorus partition to the slag phase. Alumina in such situation is believed to elongate the silicate slag structure by forming [AlO45-]-tetrahedra. However, it is apparent that for higher alumina, lower silica slags the behavior of alumina changes and dephosphorization would

Increasing Dietary Phosphorus Intake from Food Additives: Potential for Negative Impact on Bone Health123

PubMed Central

Takeda, Eiji; Yamamoto, Hironori; Yamanaka-Okumura, Hisami; Taketani, Yutaka

2014-01-01

It is important to consider whether habitual high phosphorus intake adversely affects bone health, because phosphorus intake has been increasing, whereas calcium intake has been decreasing in dietary patterns. A higher total habitual dietary phosphorus intake has been associated with higher serum parathyroid hormone (PTH) and lower serum calcium concentrations in healthy individuals. Higher serum PTH concentrations have been shown in those who consume foods with phosphorus additives. These findings suggest that long-term dietary phosphorus loads and long-term hyperphosphatemia may have important negative effects on bone health. In contrast, PTH concentrations did not increase as a result of high dietary phosphorus intake when phosphorus was provided with adequate amounts of calcium. Intake of foods with a ratio of calcium to phosphorus close to that found in dairy products led to positive effects on bone health. Several randomized controlled trials have shown positive relations between dairy intake and bone mineral density. In our loading test with a low-calcium, high-phosphorus lunch provided to healthy young men, serum PTH concentrations showed peaks at 1 and 6 h, and serum fibroblast growth factor 23 (FGF23) concentrations increased significantly at 8 h after the meal. In contrast, the high-calcium, high-phosphorus meal suppressed the second PTH and FGF23 elevations until 8 h after the meal. This implies that adequate dietary calcium intake is needed to overcome the interfering effects of high phosphorus intake on PTH and FGF23 secretion. FGF23 acts on the parathyroid gland to decrease PTH mRNA and PTH secretion in rats with normal kidney function. However, increased serum FGF23 is an early alteration of mineral metabolism in chronic kidney disease, causing secondary hyperthyroidism, and implying resistance of the parathyroid gland to the action of FGF23 in chronic kidney disease. These findings suggest that long-term high-phosphorus diets may impair bone health

Where is the Phosphorus in Cometary Volatiles?

NASA Astrophysics Data System (ADS)

Boice, Daniel C.; de Almeida, Amaury

2015-08-01

Phosphorus is a key element in all living organisms but its role in life's origin is not well understood. Phosphorus-bearing compounds have been observed in space, are ubiquitous in meteorites in small quantities, and have been detected as part of the dust component in comets Halley and Wild 2. However, searches for P-bearing species in the gas phase in cometary comae have been unsuccessful. We present results of the first quantitative study of P-bearing molecules in comets to identify likely species containing phosphorus. We found reaction pathways of gas-phase and photolytic chemistry for simple P-bearing molecules likely to be found in comets and important for prebiotic chemistry. We hope to aid future searches for this important element, especially the Rosetta Mission to Comet 67P/Churyumov-Gerasimenko, possibly shedding light on issues of comet formation (time and place) and understanding prebiotic to biotic evolution of life.Acknowledgements: We greatly appreciate support from the NSF Planetary Astronomy Program under Grant No. 0908529 and the Instituto de Astronomia, Geofísica e Ciências Atmosféricas at the University of São Paulo.

Effects of phase-feeding dietary phosphorus on survival, growth, and processing characteristics of rainbow trout Oncorhynchus mykiss

USGS Publications Warehouse

Lellis, W.A.; Barrows, F.T.; Hardy, R.W.

2004-01-01

A factorial experiment involving eight diets and three feeding periods was conducted to determine the minimal level of dietary phosphorus required to maintain survival, growth, and processing characteristics of post-juvenile rainbow trout. Trout were reared to an average size of 200, 300, or 400 g using a commercial feed (1.20% P), then allotted by triplicate groups of nine fish to one of seven experimental diets containing logarithmic increments of dietary phosphorus (0.15%%, 0.21%, 0.30%, 0.42%, 0.60%, 0.85%, and 1.20% P) or a commercial trout feed (1.20% P). At an average weight of 550 g, fish were transported to a commercial processing plant, mechanically filleted, and evaluated for quality. Fish survival and weight gain increased quadratically with increased dietary phosphorus for fish started on treatment at 200 and 300 g, but were similar among all fish started at 400 g. Phosphorus retention decreased with increasing dietary phosphorus level, from approximately 88% in groups fed diets containing 0.21% phosphorus to between 23% and 32% in groups fed diets containing 0.85% phosphorus. Calculated phosphorus losses increased as dietary phosphorus levels increased, from a low of approximately 0.4 g phosphorus kg-1 fish weight gain to between 9.5 and 13 g phosphorus kg-1 fish weight gain at the highest dietary phosphorus level. Dietary phosphorus did not affect carcass moisture, protein, lipid, or ash, but carcass phosphorus increased with increased dietary phosphorus among fish started on treatment at 200 and 300 g. There were no differences among any treatment group in carcass dressing or finishing percentage, or visual or textural appeal. The results indicate that available phosphorus levels can be reduced in rainbow trout diets to 0.60% at 200 g, to 0.30% at 300 g, or to 0.15% at 400 g live weight without loss in production or product quality in fish harvested at 550 g. Using these phase-feeding strategies would reduce the amount of phosphorus fed to the fish

The burning issue of white phosphorus: a case report and review of the literature.

PubMed

Aviv, Uri; Kornhaber, Rachel; Harats, Moti; Haik, Josef

2017-01-01

Burns from white phosphorus are rare and remain a challenge for clinicians. White phosphorus burns are often associated with smaller surface areas and high morbidity rates. Classed as a chemical burn, white phosphorus is used for military purposes and within industry, for the manufacture of fireworks and agricultural products. In this report, we discuss the case of a 40 years old female who sustained 2% Total Body Surface Area partial to full thickness burns from white phosphorus. The burns were treated conservatively with mafenide acetate on the medial calf and dorsum of foot and Flaminal Forte was used for the palmar region. The patient was discharged 22 days after admission and followed up in the outpatient clinic. Despite the use of pressure garments, hypertrophic scarring began to develop on the dorsum of her right foot. During peacetime, white phosphorus possess a significant danger to civilians. Awareness of the unique nature of white phosphorus among military burn clinicians should be emphasized.

Factors affecting phosphorus transport at a conventionally-farmed site in Lancaster County, Pennsylvania, 1992-95

USGS Publications Warehouse

Galeone, Daniel G.

1996-01-01

The U.S. Geological Survey and the Bureau of Land and Water Conservation of the Pennsylvania Department of Environmental Protection conducted a cooperative study to determine the effects of manure application and antecedent soil-phosphorus concentrations on the transport of phosphorus from the soil of a typical farm site in Lancaster County, Pa., from September 1992 to March 1995. The relation between concentrations of soil phosphorus and phosphorus transport needs to be identified because excessive phosphorus concentrations in surface-water bodies promote eutrophication.The objective of the study was to quantify and determine the significance of chemical, physical, and hydrologic factors that affected phosphorus transport. Three study plots less than 1 acre in size were tilled and planted in silage corn. Phosphorus in the form of liquid swine and dairy manure was injected to a depth of 6-8 inches on two of the three study plots in May 1993 and May 1994. Plot 1 received no inputs of phosphorus from manure while plots 2 and 3 received an average of 56 and 126 kilograms of phosphorus per acre, respectively, from the two manure applications. No other fertilizer was applied to any of the study plots. From March 30, 1993, through December 31, 1993, and March 10, 1994, through August 31, 1994 (the study period), phosphorus and selected cations were measured in precipitation, manure, soil, surface runoff, subsurface flow (at 18 inches below land surface), and corn plants before harvest. All storm events that yielded surface runoff and subsurface flow were sampled. Surface runoff was analyzed for dissolved (filtered through a 0.45-micron filter) and total concentrations. Subsurface flow was only analyzed for dissolved constituents. Laboratory soil-flask experiments and geochemical modeling were conducted to determine the maximum phosphate retention capacity of sampled soils after manure applications and primary mineralogic controls in the soils that affect phosphate

Continental-scale increase in stream and lake phosphorus ...

EPA Pesticide Factsheets

Phosphorus (P) is one of two nutrients that most commonly limit the productivity of freshwater ecosystems. Widespread increases in stream and lake total phosphorus (TP) concentrations over the period 2000-2014 were identified through periodic probability surveys of thousands of water bodies in the conterminous U.S. The increases were most notable in sites where TP was initially low (e.g., less than 10 µg L-1); an analysis of sites with relatively undisturbed watersheds suggests median annual TP increases of +2.0 µg L-1 yr-1 for streams (2000 to 2014) and +1.7 µg L-1 yr-1 for lakes (2007 to 2012). Because increasing TP is observed in relatively undeveloped catchments, expected mechanisms of accelerated TP delivery to aquatic habitats, such as runoff from agriculture, stormwater and wastewater, are unlikely explanations for the observed increase over time. We examine other possible drivers, such as changes in hydrology and atmospheric deposition, and conclude that increased atmospheric delivery of P to these minimally-disturbed lakes and streams, especially through dust—an increasingly important but poorly studied source of P—is the mechanism best supported by the data and worthy of further study. Phosphorus has long been regarded as the most important nutrient controlling the eutrophication of freshwater lakes and streams. This paper describes widespread increases in stream and lake total phosphorus (TP) concentrations over the period 2000-2014 that were

The biogeochemistry of phosphorus across an alpine topographic/snow gradient

Treesearch

M. I. Litaor; T. R. Seastedt; M. D. Walker; M. Carbone; A. Townsend

2005-01-01

Phosphorus (P) availability has generally been assumed to be the limiting or co-limiting factor for plant growth in alpine environments. To test this assumption, the biogeochemistry of phosphorus (P) along an alpine topographic/snow gradient located on Niwot Ridge, Colorado Front Range was studied in the context of P limitation for plant growth. We measured the various...

Increasing phosphorus recovery from dewatering centrate in microbial electrolysis cells.

PubMed

Yuan, Pengyi; Kim, Younggy

2017-01-01

Microbial electrolysis cells (MECs) use bioelectrochemical reactions to remove organic contaminants at the bioanode and produce hydrogen gas at the cathode. High local pH conditions near the cathode can also be utilized to produce struvite from nutrient-rich wastewater. This beneficial aspect was investigated using lab-scale MECs fed with dewatering centrate collected at a local wastewater treatment plant. The main objective was to improve phosphorus recovery by examining various cathode configurations and electric current conditions. The stainless steel mesh (SSM) cathode was relatively inefficient to achieve complete phosphorus recovery because struvite crystals were smaller (a few to tens of micrometers) than the open space between mesh wires (80 µm). As a result, the use of multiple pieces of SSM also showed a limited improvement in the phosphorus recovery up to only 68% with 5 SSM pieces. Readily available organic substrates were not sufficient in the dewatering centrate, resulting in relatively low electric current density (mostly below 0.2 A/m 2 ). The slow electrode reaction did not provide sufficiently high pH conditions near the cathode for complete recovery of phosphorus as struvite. Based on these findings, additional experiments were conducted using stainless steel foil (SSF) as the cathode and acetate (12 mM) as an additional organic substrate for exoelectrogens at the bioanode. With the high electric current (>2 A/m 2 ), a thick layer of struvite crystals was formed on the SSF cathode. The phosphorus recovery increased to 96% with the increasing MEC operation time from 1 to 7 days. With the high phosphorus recovery, estimated energy requirement was relatively low at 13.8 kWh (with acetate) and 0.30 kWh (without acetate) to produce 1 kg struvite from dewatering centrate. For efficient phosphorus recovery from real wastewater, a foil-type cathode is recommended to avoid potential losses of small struvite crystals. Also, presence of readily

Strain-Modulated Bandgap and Piezo-Resistive Effect in Black Phosphorus Field-Effect Transistors.

PubMed

Zhang, Zuocheng; Li, Likai; Horng, Jason; Wang, Nai Zhou; Yang, Fangyuan; Yu, Yijun; Zhang, Yu; Chen, Guorui; Watanabe, Kenji; Taniguchi, Takashi; Chen, Xian Hui; Wang, Feng; Zhang, Yuanbo

2017-10-11

Energy bandgap largely determines the optical and electronic properties of a semiconductor. Variable bandgap therefore makes versatile functionality possible in a single material. In layered material black phosphorus, the bandgap can be modulated by the number of layers; as a result, few-layer black phosphorus has discrete bandgap values that are relevant for optoelectronic applications in the spectral range from red, in monolayer, to mid-infrared in the bulk limit. Here, we further demonstrate continuous bandgap modulation by mechanical strain applied through flexible substrates. The strain-modulated bandgap significantly alters the density of thermally activated carriers; we for the first time observe a large piezo-resistive effect in black phosphorus field-effect transistors (FETs) at room temperature. The effect opens up opportunities for future development of electromechanical transducers based on black phosphorus, and we demonstrate an ultrasensitive strain gauge constructed from black phosphorus thin crystals.

Denitrifying woodchip bioreactor and phosphorus filter pairing to minimize pollution swapping

USDA-ARS?s Scientific Manuscript database

Pairing denitrifying woodchip bioreactors and phosphorus-sorbing filters provides a unique, engineered approach for dual nutrient removal from waters impaired with both nitrogen (N) and phosphorus (P). This column study aimed to test placement of two P-filter media (acid mine drainage treatment resi...

Molecular weight distribution of phosphorus fraction of aquatic dissolved organic matter.

PubMed

Ged, Evan C; Boyer, Treavor H

2013-05-01

This study characterized dissolved organic phosphorus (DOP) that is discharged from the Everglades Agricultural Area as part of the larger pool of aquatic dissolved organic matter (DOM). Whole water samples collected at the Everglades stormwater treat area 1 West (STA-1 W) were fractionated using a batch ultrafiltration method to separate organic compounds based on apparent molecular weight (AMW). Each AMW fraction of DOM was characterized for phosphorus, carbon, nitrogen, UV absorbance, and fluorescence. The DOP content of the Everglades water matrix was characteristically variable constituting 4-56% of total phosphorus (TP) and demonstrated no correlation with dissolved organic carbon (DOC). Measured values for DOP exceeded 14μgL(-1) in four out of five sampling dates making phosphorus load reductions problematic for the stormwater treatment areas (STAs), which target inorganic phosphorus and have a goal of 10μgL(-1) as TP. The molecular weight distributions revealed 40% of DOP is high molecular weight, aromatic-rich DOM. The results of this research are expected to be of interest to environmental chemists, environmental engineers, and water resources managers because DOP presents a major obstacle to achieving TP levels <10μgL(-1). Copyright © 2013 Elsevier Ltd. All rights reserved.

Enhanced visible light photocatalytic property of red phosphorus via surface roughening

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Weibing, E-mail: lwbing@qust.edu.cn; Yue, Jiguang; Hua, Fangxia

Highlights: • Photocatalytic RhB degradation of red phosphorus was studied for the first time. • Surface rough can increase the photocatalysis reaction active sites. • Surface rough red phosphorus possesses high photocatalytic performance. • Surface rough red phosphorus has high industrial application value. - Abstract: Red phosphorus with rough surface (SRP) was prepared by catalyst-assisted hydrothermal synthesis using Co{sup 2+} catalyst. The photocatalytic Rhodamine B (RhB) degradation of red phosphorus (RP) and SRP was studied for the first time in this work. Rough surface can enhance the dye adsorption ability of RP. About 75% RhB was absorbed by SRP aftermore » 30-min adsorption in 100 ml RhB solution with concentration of 10 mg l{sup −1} in dark. After only 10 min of illumination by visible light, more than 95% RhB was degraded, indicating that SRP has a great application potential in the area of photocatalysis. The photocatalytic RhB degradation properties of RP are much weaker than those of SRP. The increase of the number of the active sites for the photocatalytic reactions, the electron mobility and the lifetime of the photogenerated electrons cause the significant improvement of the photocatalytic performance of SRP based on the experimental results obtained.« less

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…

High Serum Phosphorus Level Is Associated with Left Ventricular Diastolic Dysfunction in Peritoneal Dialysis Patients.

PubMed

Ye, Min; Tian, Na; Liu, Yanqiu; Li, Wei; Lin, Hong; Fan, Rui; Li, Cuiling; Liu, Donghong; Yao, Fengjuan

We initiated this study to explore the relationships of serum phosphorus level with left ventricular ultrasound features and diastolic function in peritoneal dialysis (PD) patients. 174 patients with end-stage renal disease (ESRD) receiving PD were enrolled in this retrospective observational study. Conventional echocardiography examination and tissue Doppler imaging (TDI) were performed in each patient. Clinical information and laboratory data were also collected. Analyses of echocardiographic features were performed according to phosphorus quartiles groups. And multivariate regression models were used to determine the association between serum phosphorus and Left ventricular diastolic dysfunction (LVDD). With the increase of serum phosphorus levels, patients on PD showed an increased tissue Doppler-derived E/e' ratio of lateral wall (P < 0.001), indicating a deterioration of left ventricular diastolic function. Steady growths of left atrium and left ventricular diameters as well as increase of left ventricular muscle mass were also observed across the increasing quartiles of phosphorus, while left ventricular ejection fraction remained normal. In a multivariate analysis, the regression coefficient for E/e' ratio in the highest phosphorus quartile was almost threefold higher relative to those in the lowest quartile group. And compared with patients in the lowest phosphorus quartile (<1.34 mmol/L) those in the highest phosphorus quartile (>1.95 mmol/L) had a more than fivefold increased odds of E/e' ratio >15. Our study showed an early impairment of left ventricular diastolic function in peritoneal dialysis patients. High serum phosphorus level was independently associated with greater risk of LVDD in these patients. Whether serum phosphorus will be a useful target for prevention or improvement of LVDD remains to be proved by further studies.

Self-Motivation Is Associated With Phosphorus Control in End-Stage Renal Disease.

PubMed

Umeukeje, Ebele M; Merighi, Joseph R; Browne, Teri; Victoroff, Jacquelyn N; Umanath, Kausik; Lewis, Julia B; Ikizler, T Alp; Wallston, Kenneth A; Cavanaugh, Kerri

2015-09-01

Hyperphosphatemia is common in end-stage renal disease and associates with mortality. Phosphate binders reduce serum phosphorus levels; however, adherence is often poor. This pilot study aims to assess patients' self-motivation to adhere to phosphate binders, its association with phosphorus control, and potential differences by race. Cross sectional design. Subjects were enrolled from one academic medical center dialysis practice from July to November 2012. Self-motivation to adhere to phosphate binders was assessed with the autonomous regulation (AR) scale (range: 1-7) and self-reported medication adherence with the Morisky Medication Adherence Scale. Linear regression models adjusting for age, sex, health literacy, and medication adherence were applied to determine associations with serum phosphorus level, including any evidence of interaction by race. Among 100 participants, mean age was 51 years (±15 years), 53% were male, 72% were non-white, 89% received hemodialysis, and mean serum phosphorus level was 5.7 ± 1.6 mg/dL. More than half (57%) reported the maximum AR score (7). Higher AR scores were noted in those reporting better health overall (P = .001) and those with higher health literacy (P = .01). AR score correlated with better medication adherence (r = 0.22; P = .02), and medication adherence was negatively associated with serum phosphorus (r = -0.40; P < .001). In subgroup analysis among non-whites, higher AR scores correlated with lower serum phosphorus (high vs lower AR score: 5.55 [1.5] vs 6.96 [2.2]; P = .01). Associations between AR score (β 95% confidence interval: -0.37 [-0.73 to -0.01]; P = .04), medication adherence (β 95% confidence interval: -0.25 [-0.42 to -0.07]; P = .01), and serum phosphorus persisted in adjusted analyses. Self-motivation was associated with phosphate binder adherence and phosphorus control, and this differed by race. Additional research is needed to determine if personalized, culturally sensitive strategies to

Determination of phosphorus in small amounts of protein samples by ICP-MS.

PubMed

Becker, J Sabine; Boulyga, Sergei F; Pickhardt, Carola; Becker, J; Buddrus, Stefan; Przybylski, Michael

2003-02-01

Inductively coupled plasma mass spectrometry (ICP-MS) is used for phosphorus determination in protein samples. A small amount of solid protein sample (down to 1 micro g) or digest (1-10 micro L) protein solution was denatured in nitric acid and hydrogen peroxide by closed-microvessel microwave digestion. Phosphorus determination was performed with an optimized analytical method using a double-focusing sector field inductively coupled plasma mass spectrometer (ICP-SFMS) and quadrupole-based ICP-MS (ICP-QMS). For quality control of phosphorus determination a certified reference material (CRM), single cell proteins (BCR 273) with a high phosphorus content of 26.8+/-0.4 mg g(-1), was analyzed. For studies on phosphorus determination in proteins while reducing the sample amount as low as possible the homogeneity of CRM BCR 273 was investigated. Relative standard deviation and measurement accuracy in ICP-QMS was within 2%, 3.5%, 11% and 12% when using CRM BCR 273 sample weights of 40 mg, 5 mg, 1 mg and 0.3 mg, respectively. The lowest possible sample weight for an accurate phosphorus analysis in protein samples by ICP-MS is discussed. The analytical method developed was applied for the analysis of homogeneous protein samples in very low amounts [1-100 micro g of solid protein sample, e.g. beta-casein or down to 1 micro L of protein or digest in solution (e.g., tau protein)]. A further reduction of the diluted protein solution volume was achieved by the application of flow injection in ICP-SFMS, which is discussed with reference to real protein digests after protein separation using 2D gel electrophoresis.The detection limits for phosphorus in biological samples were determined by ICP-SFMS down to the ng g(-1) level. The present work discusses the figure of merit for the determination of phosphorus in a small amount of protein sample with ICP-SFMS in comparison to ICP-QMS.

Influences of operational parameters on phosphorus removal in batch and continuous electrocoagulation process performance.

PubMed

Nguyen, Dinh Duc; Yoon, Yong Soo; Bui, Xuan Thanh; Kim, Sung Su; Chang, Soon Woong; Guo, Wenshan; Ngo, Huu Hao

2017-11-01

Performance of an electrocoagulation (EC) process in batch and continuous operating modes was thoroughly investigated and evaluated for enhancing wastewater phosphorus removal under various operating conditions, individually or combined with initial phosphorus concentration, wastewater conductivity, current density, and electrolysis times. The results revealed excellent phosphorus removal (72.7-100%) for both processes within 3-6 min of electrolysis, with relatively low energy requirements, i.e., less than 0.5 kWh/m 3 for treated wastewater. However, the removal efficiency of phosphorus in the continuous EC operation mode was better than that in batch mode within the scope of the study. Additionally, the rate and efficiency of phosphorus removal strongly depended on operational parameters, including wastewater conductivity, initial phosphorus concentration, current density, and electrolysis time. Based on experimental data, statistical model verification of the response surface methodology (RSM) (multiple factor optimization) was also established to provide further insights and accurately describe the interactive relationship between the process variables, thus optimizing the EC process performance. The EC process using iron electrodes is promising for improving wastewater phosphorus removal efficiency, and RSM can be a sustainable tool for predicting the performance of the EC process and explaining the influence of the process variables.

Discrete Organic Phosphorus Signatures are Evident in Pollutant Sources within a Lake Erie Tributary.

PubMed

Brooker, M R; Longnecker, K; Kujawinski, E B; Evert, M H; Mouser, P J

2018-06-19

Phosphorus loads are strongly associated with the severity of harmful algal blooms in Lake Erie, a Great Lake situated between the United States and Canada. Inorganic and total phosphorus measurements have historically been used to estimate nonpoint and point source contributions, from contributing watersheds with organic phosphorus often neglected. Here, we used ultrahigh resolution mass spectrometry to characterize the dissolved organic matter and specifically dissolved organic phosphorus composition of several nutrient pollutant source materials and aqueous samples in a Lake Erie tributary. We detected between 23 and 313 organic phosphorus formulas across our samples, with manure samples having greater abundance of phosphorus- and nitrogen containing compounds compared to other samples. Manures also were enriched in lipids and protein-like compounds. The greatest similarities were observed between the Sandusky River and wastewater treatment plant effluent (WWTP), or the Sandusky River and agricultural edge of field samples. These sample pairs shared 84% of organic compounds and 59-73% of P-containing organic compounds, respectively. This similarity suggests that agricultural and/or WWTP sources dominate the supply of organic phosphorus compounds to the river. We identify formulas shared between the river and pollutant sources that could serve as possible markers of source contamination in the tributary.

Species and distribution of inorganic and organic phosphorus in enhanced phosphorus removal aerobic granular sludge.

PubMed

Huang, Wenli; Huang, Weiwei; Li, Huifang; Lei, Zhongfang; Zhang, Zhenya; Tay, Joo Hwa; Lee, Duu-Jong

2015-10-01

The species and distribution of phosphorus (P) in an enhanced biological phosphorus removal (EBPR)-aerobic granular sludge (AGS) were fractionated and further analyzed. Results showed that microbial cells, extracellular polymeric substances (EPS) and mineral precipitates contributed about 73.7%, 17.6% and 5.3-6.4% to the total P (TP) of EBPR-AGS, respectively. Inorganic P (IP) species were orthophosphate, pyrophosphate and polyphosphate among which polyphosphate was the major P species in the AGS, cells and EPS. Monoester and diester phosphates were identified as the organic P (OP) species in the AGS and cells. Hydroxyapatite (Ca5(PO4)3OH) and calcium phosphate (Ca2(PO4)3) were the dominant P minerals accumulated in the core of the granules. Cells along with polyphosphate were mainly in the outer layer of AGS while EPS were distributed in the whole granules. Based on the above results, the distribution of IP and OP species in AGS has been conceived. Copyright © 2015 Elsevier Ltd. All rights reserved.

Phosphorus-supported ligands for the assembly of multimetal architectures.

PubMed

Chandrasekhar, Vadapalli; Murugesapandian, Balasubramanian

2009-08-18

Modeled after boron-based scorpionate ligands, acyclic and cyclic phosphorus-containing compounds possessing reactive groups can serve as excellent precursors for the assembly of novel phosphorus-supported ligands that can coordinate multiple sites. In such ligands, the phosphorus atom does not have any role in coordination but is used as a structural support to assemble one or more coordination platforms. In this Account, we describe the utility of inorganic heterocyclic rings such as cyclophosphazenes and carbophosphazenes as well as acyclic phosphorus-containing compounds such as (S)PCl(3), RP(O)Cl(2), and R(2)P(O)Cl for building such multisite coordination platforms. We can modulate the number and orientation of such coordination platforms through the choice of the phosphorus-containing precursor. This methodology is quite general and modular and allows the creation of well-defined libraries of multisite coordination ligands. Phosphorus-supported pyrazolyl ligands are quite useful for building multimetallic architectures. Some of these ligands are prone to P-N bond hydrolysis upon metalation, but we have exploited the P-N bond sensitivity to generate hydrolyzed ligands in situ, which are useful to build multimetal assemblies. In addition, the intimate relationship between small molecule cyclophosphazenes and the corresponding pendant cyclophosphazene-containing polymer systems facilitated our design of polymer-supported catalysts for phosphate ester hydrolysis, plasmid DNA modification, and C-C bond formation reactions. Phosphorus hydrazides containing reactive amine groups are ideal precursors for integration into more complex ligand systems. The ligand (S)P[N(Me)N=CH-C(6)H(4)-2-OH](3) (LH(3)) contains six coordination sites, and its coordination response depends upon the oxidation state of the metal ion employed. LH(3) reacts with divalent transition metal ions to afford neutral trimetallic derivatives L(2)M(3), where the three metal ions are arranged in a

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

... 1117-AA66 Chemical Mixtures Containing Listed Forms of Phosphorus and Change in Application Process... establish those chemical mixtures containing red phosphorus or hypophosphorous acid and its salts (hereinafter ``regulated phosphorus'') that shall automatically qualify for exemption from the [[Page 31825...

Calcium and phosphorus supplementation of human milk for preterm infants.

PubMed

Harding, Jane E; Wilson, Jess; Brown, Julie

2017-02-26

Preterm infants are born with low skeletal stores of calcium and phosphorus. Preterm human milk provides insufficient calcium and phosphorus to meet the estimated needs of preterm infants for adequate growth. Supplementation of human milk with calcium and phosphorus may improve growth and development of preterm infants. To determine whether addition of calcium and phosphorus supplements to human milk leads to improved growth and bone metabolism of preterm infants without significant adverse effects. We used the standard search strategy of the Cochrane Neonatal Review Group to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 3), MEDLINE via PubMed (1966 to 14 April 2016), Embase (1980 to 14 April 2016) and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to 14 April 2016). We also searched clinical trials databases (11 May 2016) and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials. Randomised and quasi-randomised trials comparing supplementation of human milk with calcium and/or phosphorus versus no supplementation in hospitalised preterm infants were eligible for inclusion in this review. Two review authors (JB, JW) independently extracted data and assessed trial quality using standard methods of the Cochrane Neonatal Review Group. We reported dichotomous data as risk ratios (RRs) and continuous data as mean differences (MDs) with 95% confidence intervals (CIs). We used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess the quality of evidence. This is an update of a 2001 review that identified no eligible trials. One trial including 40 infants met the inclusion criteria for this review. Using GRADE criteria, we judged the quality of the evidence as low owing to risk of bias (inadequate reporting of methods of randomisation, allocation concealment and/or blinding) and imprecision (wide confidence intervals and

Quantifying phosphorus levels in soils, plants, surface water, and shallow groundwater associated with bahiagrass-based pastures.

PubMed

Sigua, Gilbert C; Hubbard, Robert K; Coleman, Samuel W

2010-01-01

Recent assessments of water quality status have identified eutrophication as one of the major causes of water quality 'impairment' not only in the USA but also around the world. In most cases, eutrophication has accelerated by increased inputs of phosphorus due to intensification of crop and animal production systems since the early 1990 s. Despite substantial measurements using both laboratory and field techniques, little is known about the spatial and temporal variability of phosphorus dynamics across landscapes, especially in agricultural landscapes with cow-calf operations. Critical to determining environmental balance and accountability is an understanding of phosphorus excreted by animals, phosphorus removal by plants, acceptable losses of phosphorus within the manure management and crop production systems into soil and waters, and export of phosphorus off-farm. Further research effort on optimizing forage-based cow-calf operations to improve pasture sustainability and protect water quality is therefore warranted. We hypothesized that properly managed cow-calf operations in subtropical agroecosystem would not be major contributors to excess loads of phosphorus in surface and ground water. To verify our hypothesis, we examined the comparative concentrations of total phosphorus among soils, forage, surface water, and groundwater beneath bahiagrass-based pastures with cow-calf operations in central Florida, USA. Soil samples were collected at 0-20; 20-40, 40-60, and 60-100 cm across the landscape (top slope, middle slope, and bottom slope) of 8 ha pasture in the fall and spring of 2004 to 2006. Forage availability and phosphorus uptake of bahiagrass were also measured from the top slope, middle slope, and bottom slope. Bi-weekly (2004-2006) groundwater and surface water samples were taken from wells located at top slope, middle slope, and bottom slope, and from the runoff/seepage area. Concentrations of phosphorus in soils, forage, surface water, and shallow

Phosphorus Transport in Rivers.

DTIC Science & Technology

1978-11-01

be attributed to excessive nutrient inputs to the lake. These nutrients sti- mulate the phytoplankton (algae) growth which yields excess growth. The...phosphorus in relation to the restoration of Lake Erie. The various computational techniques presented herein aid in the understanding of total...as caused by the absorption on clay materials and by assimilation by periphyton . Other investigators have found correlations between flow and other

Dissolved organic phosphorus speciation in the waters of the Tamar estuary (SW England)

NASA Astrophysics Data System (ADS)

Monbet, Phil; McKelvie, Ian D.; Worsfold, Paul J.

2009-02-01

The speciation of dissolved organic phosphorus (DOP) in the temperate Tamar estuary of SW England is described. Eight stations from the riverine to marine end-members were sampled during four seasonal campaigns in 2007 and the DOP pool in the water column and sediment porewater was characterized and quantified using a flow injection manifold after sequential enzymatic hydrolysis. This enabled the enzymatically hydrolysable phosphorus (EHP) fraction and its component labile monoester phosphates, diester phosphates and a phytase-hydrolysable fraction that includes myo-inositol hexakisphosphate (phytic acid), to be determined and compared with the total DOP, dissolved reactive phosphorus (DRP) and total dissolved phosphorus (TDP) pools. The results showed that the DOP pool in the water column varied temporally and spatially within the estuary (1.1-22 μg L -1) and constituted 6-40% of TDP. The EHP fraction of DOP ranged from 1.1-15 μg L -1 and represented a significant and potentially bioavailable phosphorus fraction. Furthermore the spatial profiles of the three components of the EHP pool generally showed non-conservative behavior along the salinity gradient, with apparent internal estuarine sources. Porewater profiles followed broadly similar trends but were notably higher at the marine station throughout the year. In contrast to soil organic phosphorus profiles, the labile monoester phosphate fraction was the largest component, with diester phosphates also prevalent. Phytic acid concentrations were higher in the lower estuary, possibly due to salinity induced desorption processes. The EHP fraction is not commonly determined in aquatic systems due to the lack of a suitable measurement technique and the Tamar results reported here have important implications for phosphorus biogeochemistry, estuarine ecology and the development of efficient strategies for limiting the effects of phosphorus on water quality.

The detection of phosphorus in the tissue of bomb victims in Gaza.

PubMed

Thomsen, Jørgen L; Worm-Leonhard, Martin

2010-01-01

One of the authors went on a fact finding mission to Gaza immediately after the termination of the Israeli invasion. One of the allegations towards the invading Israeli army was the use of phosphorus bombs. The author was able to take samples of tissue from burn victims. Attempts were made to demonstrate the presence of phosphorus in the burn wounds. Using histology and Raman spectroscopy it was found with a high degree of probability that phosphorus was present, although it was not proven with absolute certainty.

Large improvement of phosphorus incorporation efficiency in n-type chemical vapor deposition of diamond

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ohtani, Ryota; Yamamoto, Takashi; Janssens, Stoffel D.

2014-12-08

Microwave plasma enhanced chemical vapor deposition is a promising way to generate n-type, e.g., phosphorus-doped, diamond layers for the fabrication of electronic components, which can operate at extreme conditions. However, a deeper understanding of the doping process is lacking and low phosphorus incorporation efficiencies are generally observed. In this work, it is shown that systematically changing the internal design of a non-commercial chemical vapor deposition chamber, used to grow diamond layers, leads to a large increase of the phosphorus doping efficiency in diamond, produced in this device, without compromising its electronic properties. Compared to the initial reactor design, the dopingmore » efficiency is about 100 times higher, reaching 10%, and for a very broad doping range, the doping efficiency remains highly constant. It is hypothesized that redesigning the deposition chamber generates a higher flow of active phosphorus species towards the substrate, thereby increasing phosphorus incorporation in diamond and reducing deposition of phosphorus species at reactor walls, which additionally reduces undesirable memory effects.« less

Phosphorus Flow Analysis for Food Production and Consumption

NASA Astrophysics Data System (ADS)

Matsubae, Kazuyo; Nakajima, Kenichi; Nansai, Keisuke; Nagasaka, Tetsuya

Phosphorus is present only as a trace element on the Earth, but is one of the important strategic resources for agricultural food production and for the chemical industry. Natural phosphate ore is traded worldwide, mainly as a raw material for fertilizer. Approximately 147 × 103 kt of phosphate ore was mined in the world during 2005. Of this, 24.7% (36.3 × 103 kt) was produced in the USA, 20.7% (30.4 × 103 kt) in China, and 17.1% (25.2 × 103 kt) in Morocco, while there are essentially no deposits of phosphate ore in Japan or the EU (USGS,2012). It is of concern that, due to growing world demand for fertilizers, deposits of high-grade phosphate ore could be exhausted within the next 100 years (Vaccari 2009), and the average price of the ore in 2008 was approximately doubled that in 2007. Concerning the restricted supplies of phosphorus resource, it is important to consider the quantity and availability of phosphorus resources that currently remain untapped.

Modelling of in-stream nitrogen and phosphorus concentrations using different sampling strategies for calibration data

NASA Astrophysics Data System (ADS)

Jomaa, Seifeddine; Jiang, Sanyuan; Yang, Xiaoqiang; Rode, Michael

2016-04-01

It is known that a good evaluation and prediction of surface water pollution is mainly limited by the monitoring strategy and the capability of the hydrological water quality model to reproduce the internal processes. To this end, a compromise sampling frequency, which can reflect the dynamical behaviour of leached nutrient fluxes responding to changes in land use, agriculture practices and point sources, and appropriate process-based water quality model are required. The objective of this study was to test the identification of hydrological water quality model parameters (nitrogen and phosphorus) under two different monitoring strategies: (1) regular grab-sampling approach and (2) regular grab-sampling with additional monitoring during the hydrological events using automatic samplers. First, the semi-distributed hydrological water quality HYPE (Hydrological Predictions for the Environment) model was successfully calibrated (1994-1998) for discharge (NSE = 0.86), nitrate-N (lowest NSE for nitrate-N load = 0.69), particulate phosphorus and soluble phosphorus in the Selke catchment (463 km2, central Germany) for the period 1994-1998 using regular grab-sampling approach (biweekly to monthly for nitrogen and phosphorus concentrations). Second, the model was successfully validated during the period 1999-2010 for discharge, nitrate-N, particulate-phosphorus and soluble-phosphorus (lowest NSE for soluble phosphorus load = 0.54). Results, showed that when additional sampling during the events with random grab-sampling approach was used (period 2011-2013), the hydrological model could reproduce only the nitrate-N and soluble phosphorus concentrations reasonably well. However, when additional sampling during the hydrological events was considered, the HYPE model could not represent the measured particulate phosphorus. This reflects the importance of suspended sediment during the hydrological events increasing the concentrations of particulate phosphorus. The HYPE model could

Phosphorus as indicator of magmatic olivine residence time, morphology and growth rate

NASA Astrophysics Data System (ADS)

Sobolev, Alexander; Batanova, Valentina

2015-04-01

Phosphorus is among of slowest elements by diffusion rate in silicate melts and crystals (e.g. Spandler et al, 2007). In the same time it is moderately incompatible to compatible with olivine (Brunet & Chazot, 2001; Grant & Kohn, 2013). This makes phosphorus valuable tracer of olivine crystallization in natural conditions. Indeed, it is shown that natural magmatic olivine crystals commonly posses strong and complicated zoning in phosphorus (Milman-Barris et al, 2008; Welsch et al, 2014). In this paper we intend to review phosphorus behavior in olivine in published experimental and natural olivine studies and present large set of new EPMA data on phosphorus zoning in olivine phenocrysts from MORBs, OIBs, komatiites and kimberlites. We will show that sharp olivine zones enriched in phosphorus by a factor of 10-20 over prediction by equilibrium partition may be due to formation of P-rich boundary layer on the interface of fast growing olivine. This is proved by finding of small-size (normally 10 mkm or less) exceptionally P-rich melt inclusions in olivine, which are otherwise similar in composition to typical melt. These observations could provide potential olivine growth speedometer. We will also demonstrate, that sharp zoning in phosphorus may provide valuable information on the residence time of olivine crystals in different environments: magma chambers and conduits as well as mantle sources. This study has been founded by Russian Science Foundation grant 14-17-00491. References: Spandler, et al, 2007, Nature, v. 447, p. 303-306; Brunet & Chazot, 2001, Chemical Geology, v. 176, p. 51-72; Grant & Kohn, 2013, American Mineralogist, v. 98, p. 1860-1869; Milman-Barris et al, 2008, Contr. Min. Petrol. v. 155, p.739-765; Welsch et al, 2014, Geology, v. 42, p.867-870.

Watershed nitrogen and phosphorus balance: The upper Potomac River basin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jaworski, N.A.; Groffman, P.M.; Keller, A.A.

1992-01-01

Nitrogen and phosphorus mass balances were estimated for the portion of the Potomac River basin watershed located above Washington, D.C. The total nitrogen (N) balance included seven input source terms, six sinks, and one 'change-in-storage' term, but was simplified to five input terms and three output terms. The phosphorus (P) baance had four input and three output terms. The estimated balances are based on watershed data from seven information sources. Major sources of nitrogen are animal waste and atmospheric deposition. The major sources of phosphorus are animal waste and fertilizer. The major sink for nitrogen is combined denitrification, volatilization, andmore » change-in-storage. The major sink for phosphorus is change-in-storage. River exports of N and P were 17% and 8%, respectively, of the total N and P inputs. Over 60% of the N and P were volatilized or stored. The major input and output terms on the budget are estimated from direct measurements, but the change-in-storage term is calculated by difference. The factors regulating retention and storage processes are discussed and research needs are identified.« less

Urban phosphorus sustainability: Systemically incorporating social, ecological, and technological factors into phosphorus flow analysis

Treesearch

Genevieve S. Metson; David M. Iwaniec; Lawrence A. Baker; Elena M. Bennett; Daniel L. Childers; Dana Cordell; Nancy B. Grimm; J. Morgan Grove; Daniel A. Nidzgorski; Stuart White

2015-01-01

Phosphorus (P) is an essential fertilizer for agricultural production but is also a potent aquatic pollutant. Current P management fails to adequately address both the issue of food security due to P scarcity and P pollution threats to water bodies. As centers of food consumption and waste production, cities transport and store much P and thus provide important...

Incorporating phosphorus cycling into global modeling efforts: a worthwhile, tractable endeavor

USGS Publications Warehouse

Reed, Sasha C.; Yang, Xiaojuan; Thornton, Peter E.

2015-01-01

Myriad field, laboratory, and modeling studies show that nutrient availability plays a fundamental role in regulating CO2 exchange between the Earth's biosphere and atmosphere, and in determining how carbon pools and fluxes respond to climatic change. Accordingly, global models that incorporate coupled climate–carbon cycle feedbacks made a significant advance with the introduction of a prognostic nitrogen cycle. Here we propose that incorporating phosphorus cycling represents an important next step in coupled climate–carbon cycling model development, particularly for lowland tropical forests where phosphorus availability is often presumed to limit primary production. We highlight challenges to including phosphorus in modeling efforts and provide suggestions for how to move forward.

Spatial-temporal variations of phosphorus fractions in surface water and suspended particles in the Daliao River Estuary, Northeast China.

PubMed

Zhang, Lei; Qin, Yanwen; Han, Chaonan; Cao, Wei; Ma, Yingqun; Shi, Yao; Liu, Zhichao; Yang, Chenchen

2016-08-01

The transport and storage of phosphorus in estuary is a complex biogeochemical process as the result of the convergence of fresh and saline water. The objective of the current study is to investigate the spatial-temporal variations of phosphorus fractions in surface water and suspended particles of Daliao River Estuary, China. Samples were collected in August (wet season) and November (dry season), 2013. The results showed that total particulate phosphorus (TPP) in water accounted for more than 50 % of the total phosphorus (TP). Meanwhile, in suspended particles, more than 62 % of particulate phosphorus was in the form of bioavailable phosphorus, including exchangeable phosphorus (Exc-P), extractable organic phosphorus (Exo-P), and iron-bound phosphorus (Fe-P), which meant that the potential impacts of bioavailable phosphorus in suspended particles on estuarine water environment cannot be ignored. There were significantly seasonal variations of phosphorus fractions in the Daliao River Estuary. The concentrations of phosphorus fractions in water in wet season were much lower than that in dry season because of the dilution effect of larger rainfall in wet season. In addition, spatial distribution characteristics of phosphorus fractions were also obvious. Due to terrigenous phosphorus input from the upstream of tidal reach and seawater dilution effect in coastal estuary, total dissolved phosphorus (TDP) concentrations in water gradually decreased from tidal reach to coastal estuary. However, the concentrations of TPP and TP in water and Exo-P in suspended particles presented spatial fluctuation, and these were greatly attributed to sediment re-suspension in coastal estuary.

High performance of nitrogen and phosphorus removal in an electrolysis-integrated biofilter.

PubMed

Gao, Y; Xie, Y W; Zhang, Q; Yu, Y X; Yang, L Y

A novel electrolysis-integrated biofilter system was developed in this study to evaluate the intensified removal of nitrogen and phosphorus from contaminated water. Two laboratory-scale biofilter systems were established, one with electrolysis (E-BF) and one without electrolysis (BF) as control. The dynamics of intensified nitrogen and phosphorus removal and the changes of inflow and outflow water qualities were also evaluated. The total nitrogen (TN) removal rate was 94.4% in our newly developed E-BF, but only 74.7% in the control BF. Ammonium removal rate was up to 95% in biofilters with or without electrolysis integration with an influent ammonium concentration of 40 mg/L, and the accumulation of nitrate and nitrite was much lower in the effluent of E-BF than that of BF. Thus electrolysis plays an important role in TN removal especially the nitrate and nitrite removal. Phosphorus removal was significantly enhanced, exceeding 90% in E-BF by chemical precipitation, physical adsorption, and flocculation of phosphorus because of the in situ formation of ferric ions by the anodizing of sacrificial iron anodes. Results from this study indicate that the electrolysis integrated biofilter is a promising solution for intensified nitrogen and phosphorus removal.

The rising star of 2D black phosphorus beyond graphene: synthesis, properties and electronic applications

NASA Astrophysics Data System (ADS)

Chen, Pengfei; Li, Neng; Chen, Xingzhu; Ong, Wee-Jun; Zhao, Xiujian

2018-01-01

Black phosphorus, which is a relatively rare allotrope of phosphorus, was first discovered by Bridgman in 1914. Since the advent of two-dimensional (2D) black phosphorus (which is known as phosphorene due to its resembling graphene sheets) in early 2014, research interest in the arena of black phosphorus was reignited in the scientific and technological communities. Henceforth, a myriad of research studies on this new member of the 2D world have been extensively emerged. Fascinatingly, 2D black phosphorus exhibits a distinctive wrinkled structure with the high hole mobility up to 1000 cm2 V-1 s-1, excellent mechanical properties, tunable band structures, anisotropic thermal, electrical and optical properties, thus leading to its marvelous prospects in device applications. This review firstly introduces the state-of-the-art development, structural properties and preparation routes of black phosphorus. In particular, anisotropy involved in mechanical properties, thermal conductivity, carrier transport as well as optical properties is comprehensively discussed. Apart from discussing the recent progress in black phosphorus which is applied to devices (i.e. field effect transistors and optoelectronic), the review also highlights the bottlenecks encountered by the society and finally casts an invigorating perspective and insightful outlook on the future direction of the next-generation 2D black phosphorus by harnessing its remarkable characteristics for energy production.

Antibody to fibroblast growth factor 23-peptide reduces excreta phosphorus of laying hens.

PubMed

Ren, Zhouzheng; Ebrahimi, Marziyeh; Bütz, Daniel E; Sand, Jordan M; Zhang, Keying; Cook, Mark E

2017-01-01

Novel strategies to minimize the excretion of phosphorus in swine and poultry are critical in minimizing environmental degradation. We have developed a synthetic peptide vaccine to produce autoantibodies to fibroblast growth factor 23 (FGF-23), a bone-derived hormone that blocks kidney phosphate resorption and indirectly reduces intestinal phosphate absorption. Single Comb White Leghorn laying hens, fed a standard diet (inorganic phosphorus, Pi = 0.4%), were immunized over the course of 4 weeks with either a FGF-23 peptide vaccine or adjuvant control (without FGF-23 peptide). At peak antibody titer to the peptide (week 5), 24-h excreta were collected and hens were blood sampled (represents 0.4% Pi treatment). Hens were then fed a 0.8% Pi diet and blood was sampled at 24 and 72 h and 24-h excreta were collected at 12 to 36 and 60 to 84 h (represents 0.8% Pi treatment). Increasing Pi from 0.4 to 0.8% increased (P < 0.05) percent excreta phosphorus, total 24-h phosphorus excretion, and plasma levels of FGF-23 and phosphate in either control or FGF-23 peptide vaccinated hens as early as the first sampling period. FGF-23 peptide vaccinated hens fed 0.4% Pi had reduced (P < 0.05) percent excreta phosphorus, total 24 h phosphorus excretion, and plasma levels of FGF-23 and iPTH, and increased (P < 0.05) plasma levels of phosphate and 1,25(OH) 2 D 3 when compared to control vaccinated hens fed 0.4% Pi. In the first collection period post 0.8% Pi feeding, FGF-23 peptide vaccinated hens had reduced (P < 0.05) plasma levels of FGF-23 and iPTH, and increased (P < 0.05) plasma levels of phosphate and 1,25(OH) 2 D 3 , and tended to have reduced percent excreta phosphorus (P = 0.085) and total 24 h phosphorus excretion (P = 0.078) when compared to control vaccinated hens. Results during the second collection period post 0.8% Pi feeding were similar to that at the first collection period. These results are the first to show that the inhibition of FGF-23 action by

Flow analysis techniques for phosphorus: an overview.

PubMed

Estela, José Manuel; Cerdà, Víctor

2005-04-15

A bibliographical review on the implementation and the results obtained in the use of different flow analytical techniques for the determination of phosphorus is carried out. The sources, occurrence and importance of phosphorus together with several aspects regarding the analysis and terminology used in the determination of this element are briefly described. A classification as well as a brief description of the basis, advantages and disadvantages of the different existing flow techniques, namely; segmented flow analysis (SFA), flow injection analysis (FIA), sequential injection analysis (SIA), all injection analysis (AIA), batch injection analysis (BIA), multicommutated FIA (MCFIA), multisyringe FIA (MSFIA) and multipumped FIA (MPFIA) is also carried out. The most relevant manuscripts regarding the analysis of phosphorus by means of flow techniques are herein classified according to the detection instrumental technique used with the aim to facilitate their study and obtain an overall scope. Finally, the analytical characteristics of numerous flow-methods reported in the literature are provided in the form of a table and their applicability to samples with different matrixes, namely water samples (marine, river, estuarine, waste, industrial, drinking, etc.), soils leachates, plant leaves, toothpaste, detergents, foodstuffs (wine, orange juice, milk), biological samples, sugars, fertilizer, hydroponic solutions, soils extracts and cyanobacterial biofilms are tabulated.

A brief history of phosphorus: from the philosopher's stone to nutrient recovery and reuse.

PubMed

Ashley, K; Cordell, D; Mavinic, D

2011-08-01

The element phosphorus has no substitute in sustaining all life and food production on our planet. Yet today's phosphorus use patterns have resulted in both a global environmental epidemic of eutrophication and led to a situation where the future availability of the world's main sources of phosphorus is uncertain. This paper examines the important history of human interference with the phosphorus cycle from initial discovery to present, highlighting key interrelated events and consequences of the Industrial Revolution, Sanitation Revolution and Green Revolution. Whilst these events led to profound advances in technology, public health and food production, they have fundamentally broken the global phosphorus cycle. It is clear a 'Fourth Revolution' is required to resolve this dilemma and ensure humanity can continue to feed itself into the future while protecting environmental and human health. Copyright © 2011 Elsevier Ltd. All rights reserved.

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 ...

Measurement of spin-flip probabilities for ultracold neutrons interacting with nickel phosphorus coated surfaces

DOE PAGES

Tang, Zhaowen; Adamek, Evan Robert; Brandt, Aaron; ...

2016-04-26

In this paper, we report a measurement of the spin-flip probabilities for ultracold neutrons interacting with surfaces coated with nickel phosphorus. For 50 μm thick nickel phosphorus coated on stainless steel, the spin-flip probability per bounce was found to be β NiP on SS = (3.3 +1.8, -5.6) X 10 -6. For 50 μm thick nickel phosphorus coated on aluminum, the spin-flip probability per bounce was found to be β NiP on Al = (3.6 +2.1, -5.9) X 10 -6. For the copper guide used as reference, the spin flip probability per bounce was found to be β Cu =more » (6.7 + 5.0, -2.5) X 10 -6. The results on the nickel phosphorus-coated surfaces may be interpreted as upper limits, yielding β NiP on SS < 6.2 X 10 -6 (90% C.L.) and β NiP on Al < 7.0 X 10 -6 (90% C.L.) for 50 μm thick nickel phosphorus coated on stainless steel and 50 μm thick nickel phosphorus coated on aluminum, respectively. Finally, nickel phosphorus coated stainless steel or aluminum provides a solution when low-cost, mechanically robust, and non-depolarizing UCN guides with a high Fermi potential are needed.« less

Effect of fire on phosphorus forms in Sphagnum moss and peat soils of ombrotrophic bogs.

PubMed

Wang, Guoping; Yu, Xiaofei; Bao, Kunshan; Xing, Wei; Gao, Chuanyu; Lin, Qianxin; Lu, Xianguo

2015-01-01

The effect of burning Sphagnum moss and peat on phosphorus forms was studied with controlled combustion in the laboratory. Two fire treatments, a light fire (250 °C) and a severe fire (600 °C), were performed in a muffle furnace with 1-h residence time to simulate the effects of different forest fire conditions. The results showed that fire burning Sphagnum moss and peat soils resulted in losses of organic phosphorus (Po), while inorganic phosphorus (Pi) concentrations increased. Burning significantly changed detailed phosphorus composition and availability, with severe fires destroying over 90% of organic phosphorus and increasing the availability of inorganic P by more than twofold. Our study suggest that, while decomposition processes in ombrotrophic bogs occur very slowly, rapid changes in the form and availability of phosphorus in vegetation and litter may occur as the result of forest fires on peat soils. Copyright © 2014 Elsevier Ltd. All rights reserved.

Phosphorus Availability, Phytoplankton Community Dynamics, and Taxon-Specific Phosphorus Status in the Gulf of Aqaba, Red Sea

NASA Astrophysics Data System (ADS)

Mackey, K. R.; Labiosa, R. G.; Calhoun, M.; Street, J. H.; Post, A. F.; Paytan, A.

2006-12-01

The relationships among phytoplankton taxon-specific phosphorus-status, phytoplankton community composition, and nutrient levels were assessed over three seasons in the Gulf of Aqaba, Red Sea. During summer and fall, stratified surface waters were depleted of nutrients and picophytoplankton populations comprised the majority of cells (80% and 88% respectively). In winter, surface nutrient concentrations were higher and larger phytoplankton were more abundant (63%). Cell specific alkaline phosphatase activity (APA) derived from enzyme labeled fluorescence was consistently low (less than 5%) in the picophytoplankton throughout the year, whereas larger cells expressed elevated APA during the summer and fall but less in the winter. A nutrient addition bioassay during the fall showed that, relative to control, APA was reduced by half in larger cells following addition of orthophosphate, whereas the APA of picophytoplankton remained low (less than 1%) across all treatments and the control. These results indicate that the most abundant phytoplankton are not limited by orthophosphate and only some subpopulations (particularly of larger cells) exhibit orthophosphate-limitation throughout the year. Our results indicate that orthophosphate availability influences phytoplankton ecology, correlating with shifts in phytoplankton community structure and the nutrient status of individual cells. The role of dissolved organic phosphorus as an important phosphorus source for marine phytoplankton in oligotrophic settings and the need for evaluating nutrient limitation at the taxa and/or single cell level (rather than inferring it from nutrient concentrations and ratios or bulk enzyme activity measurements) are highlighted.

Platelet adhesion on phosphorus-incorporated tetrahedral amorphous carbon films

NASA Astrophysics Data System (ADS)

Liu, Aiping; Zhu, Jiaqi; Liu, Meng; Dai, Zhifei; Han, Xiao; Han, Jiecai

2008-11-01

The haemocompatibility of phosphorus-incorporated tetrahedral amorphous carbon (ta-C:P) films, synthesized by filtered cathodic vacuum arc technique with PH 3 as the dopant source, was assessed by in vitro platelet adhesion tests. Results based on scanning electron microscopy and contact angle measurements reveal that phosphorus incorporation improves the wettability and blood compatibility of ta-C film. Our studies may provide a novel approach for the design and synthesis of doped ta-C films to repel platelet adhesion and reduce thrombosis risk.

Changes in phosphorus concentrations and loads in the Assabet River, Massachusetts, October 2008 through April 2014

USGS Publications Warehouse

Savoie, Jennifer G.; DeSimone, Leslie A.; Mullaney, John R.; Zimmerman, Marc J.; Waldron, Marcus C.

2016-10-24

Treated effluent discharged from municipal wastewater-treatment plants to the Assabet River in central Massachusetts includes phosphorus, which leads to increased growth of nuisance aquatic plants that decrease the river’s water quality and aesthetics in impounded reaches during the growing season. To improve the river’s water quality and aesthetics, the U.S. Environmental Protection Agency approved a total maximum daily load for phosphorus in 2004 that directed the wastewater-treatment plants to reduce the amount of total phosphorus discharged to the river by 2012. The permitted total phosphorus monthly average of 0.75 milligrams per liter during the aquatic plant growing season (April 1 through October 31) was reduced by the total maximum daily load to a target of 0.1 milligrams per liter by 2012, and the nongrowing-season limit was unchanged at 1.0 milligrams per liter.From October 2008 through April 2014, the U.S. Geological Survey, in cooperation with the Massachusetts Department of Environmental Protection, measured streamflow and collected weekly flow-proportional, composite samples of water from the Assabet River for analysis of concentrations of total phosphorus and orthophosphate. Streamflow and concentration data were used to estimate total phosphorus and orthophosphate loads in the river. The purpose of this monitoring effort was to evaluate phosphorus concentrations and loads in the river before, during, and after the wastewater-treatment-plant upgrades and to assess the effects of seasonal differences in permitted discharges. The locations of water-quality-monitoring stations, with respect to the Hudson and Ben Smith impoundments, enabled examination of effects of phosphorus entering and leaving the impoundments.Annual median concentrations of total phosphorus in wastewater-treatment plants were reduced by more than 80 percent with the plant upgrades. Measured instream annual median concentrations of total phosphorus in the Assabet River decreased

40 CFR Appendix A to Part 80 - Test for the Determination of Phosphorus in Gasoline

Code of Federal Regulations, 2011 CFR

2011-07-01

... Phosphorus in Gasoline A Appendix A to Part 80 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... 80—Test for the Determination of Phosphorus in Gasoline 1. Scope. 1.1 This method was developed for the determination of phosphorus generally present as pentavalent phosphate esters or salts, or both...

40 CFR Appendix A to Part 80 - Test for the Determination of Phosphorus in Gasoline

Code of Federal Regulations, 2010 CFR

2010-07-01

... Phosphorus in Gasoline A Appendix A to Part 80 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... 80—Test for the Determination of Phosphorus in Gasoline 1. Scope. 1.1 This method was developed for the determination of phosphorus generally present as pentavalent phosphate esters or salts, or both...

How Dietary Phosphorus Availability during Development Influences Condition and Life History Traits of the Cricket, Acheta domesticas

PubMed Central

Visanuvimol, Laksanavadee; Bertram, Susan M.

2011-01-01

Phosphorus is extremely limited in the environment, often being 10–20 times lower in plants than what invertebrate herbivores require. This mismatch between resource availability and resource need can profoundly influence herbivore life history traits and fitness. This study investigated how dietary phosphorus availability influenced invertebrate growth, development time, consumption, condition, and lifespan using juvenile European house crickets, Acheta domesticus L. (Orthoptera: Gryllidae). Crickets reared on high phosphorus diets ate more food, gained more weight, were in better condition at maturity, and contained more phosphorus, nitrogen, and carbon in their bodies at death than crickets reared on low phosphorus diets. There was also a trend for crickets reared on high phosphorus diets to become larger adults (interaction with weight prior to the start of the experiment). These findings can be added to the small but growing number of studies that reveal the importance of phosphorus to insect life history traits. Future research should explore the importance of dietary phosphorus availability relative to protein, lipid, and carbohydrate availability. PMID:21864157

Response of Douglas-fir seedlings to nitrogen, sulfur, and phosphorus fertilizers.

Treesearch

M.A. Radwan; J.S. Shumway

1985-01-01

Effects of nitrogen, sulfur, and phosphorus fertilizers on growth and nutrient content of Douglas-fir seedlings potted in Grove and Bunker forest soils were determined. Growth was primarily stimulated with nitrogen in the Grove soil and with phosphorus in the Bunker soil. Fertilization influenced nutrient levels in the seedlings. Growth results agree with observed...

Aluminum effects on uptake and metabolism of phosphorus by the Cyanobacterium Anabaena cylindrica

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pettersson, A.; Haellbom, L. Bergman, B.

Aluminum severely affects the growth of the cyanobacterium Anabaena cylindrica and induces symptoms indicating phosphorus starvation. Pre- or post-treating the cells with high (90 micromolar) phosphorus reduces the toxicity of aluminum compared to cells receiving a lower orthophosphate concentration. In this study aluminum (ranging from 9 to 36 micromolar) and phosphorus concentrations were chosen so that the precipitation of insoluble AlPO/sub 4/ never exceeded 10% of the total phosphate concentration. The uptake of /sup 32/P-phosphorus is not disturbed by aluminium either at high (100 micromolar) or low (10 micromolar) concentrations of phosphate. Also, the rapid accumulation of polyphosphate granules inmore » cells exposed to aluminum indicates that the incorporation of phosphate is not disturbed. However, a significant decrease in the mobilization of the polyphosphates is observed, as is a lowered activity of the enzyme acid phosphatase, in aluminum treated cells. We conclude that aluminum acts on the intracellular metabolism of phosphate, which eventually leads to phosphorus starvation rather than on its uptake in the cyanobacterium A. cylindrica.« less

Water hyacinth (Eichhornia crassipes) waste as an adsorbent for phosphorus removal from swine wastewater.

PubMed

Chen, Xi; Chen, Xiuxia; Wan, Xianwei; Weng, Boqi; Huang, Qin

2010-12-01

Both live plants and dried straw of water hyacinth were applied to a sequential treatment of swine wastewater for nitrogen and phosphorus reduction. In the facultative tank, the straw behaved as a kind of adsorbent toward phosphorus. Its phosphorus removal rate varied considerably with contact time between the straw and the influent. In the laboratory, the straw displayed a rapid total phosphorus reduction on a KH(2)PO(4) solution. The adsorption efficiency was about 36% upon saturation. At the same time, the water hyacinth straw in the facultative tank enhanced NH(3)-N removal efficiency as well. However, no adsorption was evident. This study demonstrated an economically feasible means to apply water hyacinth phosphorus straw for the swine wastewater treatment. The sequential system employed significantly reduced the land use, as compared to the wastewater stabilization pond treatment, for pollution amelioration of swine waste. 2010 Elsevier Ltd. All rights reserved.

A phosphorus-free anolyte to enhance coulombic efficiency of microbial fuel cells

NASA Astrophysics Data System (ADS)

Tang, Xinhua; Li, Haoran; Du, Zhuwei; Ng, How Yong

2014-12-01

In this study, a phosphorus-free anolyte is prepared by using bicarbonate to replace phosphate buffer for application in two chamber microbial fuel cells (MFCs). Optical density test and Bradford protein assay shows that this phosphorus-free anolyte effectively inhibits the growth and reproduction of microorganisms suspended in the solution and greatly reduces the suspended cell mass. As a result, it considerably enhances the coulombic efficiency (CE) of MFCs. When the acetate concentration is 11 mM, the CE of the MFC using the pH 7 phosphate-containing anolyte is 9.7% and the CE with the pH 8.3 phosphate-containing anolyte is 9.1%, while the CE of the MFC using the phosphorus-free anolyte (pH 8.3) achieves 26.6%. This study demonstrates that this phosphorus-free anolyte holds the potential to enhance the feasibility for practical applications of MFCs.

[Output characteristics of rainfall runoff phosphorus pollution from a typical small watershed in Yimeng mountainous area].

PubMed

Yu, Xing-xiu; Li, Zhen-wei; Liu, Qian-jin; Jing, Guang-hua

2012-08-01

Relationships between phosphorus pollutant concentrations and precipitation-runoff were analyzed by monitoring pollutant losses at outlets of the Menglianggu watershed in 2010. A typical small watershed was selected to examine the runoff and quality parameters such as total phosphorus (TP), particle phosphorus (PP), dissolve phosphorus (DP) and dissolve inorganic phosphorus (DIP) in rainfall-runoff of 10 rainfall events. Precipitation was above 2 mm for all the 10 rainfall events. The results showed that the peak of phosphorus concentrations occurred before the peak of water flows, whereas change processes of the phosphorus fluxes were consistent with that of the water flows and the phosphorus flux also have a strong linear relationship with the water flows. The minimums of the phosphorus concentrations in every 10 natural rainfall events have small differences with each other, but the maximum and EMCs of the phosphorus concentrations have significant differences with each rainfall event. This was mainly influenced by the precipitation, maximum rainfall intensity and mean rainfall intensity (EMCs) and was less influenced by rainfall duration. DP and TP were mainly composed of DIP and PP, respectively. There were no significant correlations between DIP/DP dynamic changes and rainfall characteristics, whereas significant correlations between PP/TP dynamic changes and maximum rainfall intensity were detected. The production of DIP, DP, AND TP were mainly influenced by the direct runoff (DR) and base flow (BF). The EMCs of DIP, DP, TP and the variations of DIP/DP were all found to have significant polynomial relationships with DR/TR., but the dynamic changes of PP/ TP and the EMCS of PP were less influenced by the DR/TR.

Low investment in sexual reproduction threatens plants adapted to phosphorus limitation.

PubMed

Fujita, Yuki; Venterink, Harry Olde; van Bodegom, Peter M; Douma, Jacob C; Heil, Gerrit W; Hölzel, Norbert; Jabłońska, Ewa; Kotowski, Wiktor; Okruszko, Tomasz; Pawlikowski, Paweł; de Ruiter, Peter C; Wassen, Martin J

2014-01-02

Plant species diversity in Eurasian wetlands and grasslands depends not only on productivity but also on the relative availability of nutrients, particularly of nitrogen and phosphorus. Here we show that the impacts of nitrogen:phosphorus stoichiometry on plant species richness can be explained by selected plant life-history traits, notably by plant investments in growth versus reproduction. In 599 Eurasian sites with herbaceous vegetation we examined the relationship between the local nutrient conditions and community-mean life-history traits. We found that compared with plants in nitrogen-limited communities, plants in phosphorus-limited communities invest little in sexual reproduction (for example, less investment in seed, shorter flowering period, longer lifespan) and have conservative leaf economy traits (that is, a low specific leaf area and a high leaf dry-matter content). Endangered species were more frequent in phosphorus-limited ecosystems and they too invested little in sexual reproduction. The results provide new insight into how plant adaptations to nutrient conditions can drive the distribution of plant species in natural ecosystems and can account for the vulnerability of endangered species.

Low investment in sexual reproduction threatens plants adapted to phosphorus limitation

NASA Astrophysics Data System (ADS)

Fujita, Yuki; Venterink, Harry Olde; van Bodegom, Peter M.; Douma, Jacob C.; Heil, Gerrit W.; Hölzel, Norbert; Jabłońska, Ewa; Kotowski, Wiktor; Okruszko, Tomasz; Pawlikowski, Paweł; de Ruiter, Peter C.; Wassen, Martin J.

2014-01-01

Plant species diversity in Eurasian wetlands and grasslands depends not only on productivity but also on the relative availability of nutrients, particularly of nitrogen and phosphorus. Here we show that the impacts of nitrogen:phosphorus stoichiometry on plant species richness can be explained by selected plant life-history traits, notably by plant investments in growth versus reproduction. In 599 Eurasian sites with herbaceous vegetation we examined the relationship between the local nutrient conditions and community-mean life-history traits. We found that compared with plants in nitrogen-limited communities, plants in phosphorus-limited communities invest little in sexual reproduction (for example, less investment in seed, shorter flowering period, longer lifespan) and have conservative leaf economy traits (that is, a low specific leaf area and a high leaf dry-matter content). Endangered species were more frequent in phosphorus-limited ecosystems and they too invested little in sexual reproduction. The results provide new insight into how plant adaptations to nutrient conditions can drive the distribution of plant species in natural ecosystems and can account for the vulnerability of endangered species.

Incorporating phosphorus cycling into global modeling efforts: a worthwhile, tractable endeavor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reed, Sasha C.; Yang, Xiaojuan; Thornton, Peter E.

2015-06-25

Myriad field, laboratory, and modeling studies show that nutrient availability plays a fundamental role in regulating CO 2 exchange between the Earth's biosphere and atmosphere, and in determining how carbon pools and fluxes respond to climatic change. Accordingly, global models that incorporate coupled climate-carbon cycle feedbacks made a significant advance with the introduction of a prognostic nitrogen cycle. Here we propose that incorporating phosphorus cycling represents an important next step in coupled climate-carbon cycling model development, particularly for lowland tropical forests where phosphorus availability is often presumed to limit primary production. We highlight challenges to including phosphorus in modeling effortsmore » and provide suggestions for how to move forward.« less

Phosphorus promotion and poisoning in zeolite-based materials: synthesis, characterisation and catalysis.

PubMed

van der Bij, Hendrik E; Weckhuysen, Bert M

2015-10-21

Phosphorus and microporous aluminosilicates, better known as zeolites, have a unique but poorly understood relationship. For example, phosphatation of the industrially important zeolite H-ZSM-5 is a well-known, relatively inexpensive and seemingly straightforward post-synthetic modification applied by the chemical industry not only to alter its hydrothermal stability and acidity, but also to increase its selectivity towards light olefins in hydrocarbon catalysis. On the other hand, phosphorus poisoning of zeolite-based catalysts, which are used for removing nitrogen oxides from exhaust fuels, poses a problem for their use in diesel engine catalysts. Despite the wide impact of phosphorus-zeolite chemistry, the exact physicochemical processes that take place require a more profound understanding. This review article provides the reader with a comprehensive and state-of-the-art overview of the academic literature, from the first reports in the late 1970s until the most recent studies. In the first part an in-depth analysis is undertaken, which will reveal universal physicochemical and structural effects of phosphorus-zeolite chemistry on the framework structure, accessibility, and strength of acid sites. The second part discusses the hydrothermal stability of zeolites and clarifies the promotional role that phosphorus plays. The third part of the review paper links the structural and physicochemical effects of phosphorus on zeolite materials with their catalytic performance in a variety of catalytic processes, including alkylation of aromatics, catalytic cracking, methanol-to-hydrocarbon processing, dehydration of bioalcohol, and ammonia selective catalytic reduction (SCR) of NOx. Based on these insights, we discuss potential applications and important directions for further research.

Spatial variation in sediment-water exchange of phosphorus in Florida Bay: AMP as a model organic compound.

PubMed

Huang, Xiao-Lan; Zhang, Jia-Zhong

2010-10-15

Dissolved organic phosphorus (DOP) has been recognized as dominant components in total dissolved phosphorus (TDP) pools in many coastal waters, and its exchange between sediment and water is an important process in biogeochemical cycle of phosphorus. Adenosine monophosphate (AMP) was employed as a model DOP compound to simulate phosphorus exchange across sediment-water interface in Florida Bay. The sorption data from 40 stations were fitted to a modified Freundlich equation and provided a detailed spatial distribution both of the sediment's zero equilibrium phosphorus concentration (EPC(0-T)) and of the distribution coefficient (K(d-T)) with respect to TDP. The K(d-T) was found to be a function of the index of phosphorus saturation (IPS), a molar ratio of the surface reactive phosphorus to the surface reactive iron oxide content in the sediment, across the entire bay. However, the EPC(0-T) was found to correlate to the contents of phosphorus in the eastern bay only. Sediment in the western bay might act as a source of the phosphorus in the exchange process due to their high EPC(0-T) and low K(d-T), whereas sediments in the eastern bay might act as a sink because of their low EPC(0-T) and high K(d-T). These results strongly support the hypothesis that both phosphorus and iron species in calcareous marine sediments play a critical role in governing the sediment-water exchange of both phosphate and DOP in the coastal and estuarine ecosystems.

Phosphorus diffusion gettering process of multicrystalline silicon using a sacrificial porous silicon layer

PubMed Central

2012-01-01

The aims of this work are to getter undesirable impurities from low-cost multicrystalline silicon (mc-Si) wafers and then enhance their electronic properties. We used an efficient process which consists of applying phosphorus diffusion into a sacrificial porous silicon (PS) layer in which the gettered impurities have been trapped after the heat treatment. As we have expected, after removing the phosphorus-rich PS layer, the electrical properties of the mc-Si wafers were significantly improved. The PS layers, realized on both sides of the mc-Si substrates, were formed by the stain-etching technique. The phosphorus treatment was achieved using a liquid POCl3-based source on both sides of the mc-Si wafers. The realized phosphorus/PS/Si/PS/phosphorus structures were annealed at a temperature ranging between 700°C and 950°C under a controlled O2 atmosphere, which allows phosphorus to diffuse throughout the PS layers and to getter eventual metal impurities towards the phosphorus-doped PS layer. The effect of this gettering procedure was investigated by means of internal quantum efficiency and the dark current–voltage (I-V) characteristics. The minority carrier lifetime measurements were made using a WTC-120 photoconductance lifetime tester. The serial resistance and the shunt resistance carried out from the dark I-V curves confirm this gettering-related solar cell improvement. It has been shown that the photovoltaic parameters of the gettered silicon solar cells were improved with regard to the ungettered one, which proves the beneficial effect of this gettering process on the conversion efficiency of the multicrystalline silicon solar cells. PMID:22846070

Anti-flammable properties of capable phosphorus-nitrogen containing triazine derivatives on cotton

USDA-ARS?s Scientific Manuscript database

Most of new phosphorus-nitrogen containing compounds were prepared by organic reactions of cyanuric chloride and phosphonates. They were characterized by analytical tools such as proton (1H), carbon (13C), and phosphorus (31P) nuclear magnetic resonance (NMR) spectroscopy and elemental analysis (EA)...

Thermal properties of wood reacted with a phosphorus pentoxide–amine system

Treesearch

Hong-Lin Lee; George C. Chen; Roger M. Rowell

2004-01-01

The objective of this research was to improve the fire-retardant properties of wood in one treatment using a phosphorus pentoxide–amine system. Phosphorus pentoxide and 16 amines including alkyl, halophenyl, and phenyl amines were compounded in N,N-dimethylformamide and the resulting solutions containing phosphoramides were reacted with wood. The characteristics of...

Reduction of Iodine by Phosphorus(I): Integration of the Rate Equation

ERIC Educational Resources Information Center

Kustin, Kenneth; Ross, Edward W.

2005-01-01

A. D. Mitchell's work on the phosphorus(I) reduction of the halogens and of mercury(II) and copper(II) chlorides is examined. A review of some salient characteristics of the Mitchell mechanism is presented, together with a discussion on how a student might benefit from a case study of the phosphorus(I) reduction of iodine or the similarly behaving…

From wastewater to fertilisers--Technical overview and critical review of European legislation governing phosphorus recycling.

PubMed

Hukari, Sirja; Hermann, Ludwig; Nättorp, Anders

2016-01-15

The present paper is based on an analysis of the EU legislation regulating phosphorus recovery and recycling from wastewater stream, in particular as fertiliser. To recover phosphorus, operators need to deal with market regulations, health and environment protection laws. Often, several permits and lengthy authorisation processes for both installation (e.g. environmental impact assessment) and the recovered phosphorus (e.g. End-of-Waste, REACH) are required. Exemptions to certain registration processes for recoverers are in place but rarely applied. National solutions are often needed. Emerging recovery and recycling sectors are affected by legislation in different ways: Wastewater treatment plants are obliged to remove phosphorus but may also recover it in low quantities for operational reasons. Permit processes allowing recovery and recycling operations next to water purification should thus be rationalised. In contrast, the fertiliser industry relies on legal quality requirements, ensuring their market reputation. For start-ups, raw-material sourcing and related legislation will be the key. Phosphorus recycling is governed by fragmented decision-making in regional administrations. Active regulatory support, such as recycling obligation or subsidies, is lacking. Legislation harmonisation, inclusion of recycled phosphorus in existing fertiliser regulations and support of new operators would speed up market penetration of novel technologies, reduce phosphorus losses and safeguard European quality standards.

Application of steel slag coated with sodium hydroxide to enhance precipitation-coagulation for phosphorus removal.

PubMed

Park, Taejun; Ampunan, Vanvimol; Maeng, Sungkyu; Chung, Eunhyea

2017-01-01

Phosphorus removal has been studied for decades to reduce the environmental impact of phosphorus in natural waterbodies. Slag has been applied for the phosphorus removal by several mechanisms. In this study, sodium hydroxide coating was applied on the slag surface to enhance the efficiency of precipitation-coagulation process. In the batch test, it was found that the capacity of the slag to maintain high pH decreases with increasing its exposure time to the aqueous solution. In the column test, the coarse-grained coated slag showed higher phosphorus removal efficiency than the fine-grained uncoated slag. The coated slag maintained pH higher than uncoated slag and, accordingly, the removal efficiency of phosphorus was higher. Especially, when pH was less than 8, the removal efficiency decreased significantly. However, coated slag provided an excess amount of aluminum and sodium. Thus, a return process to reuse aluminum and sodium as a coagulant was introduced. The return process yields longer lifespan of slag with higher phosphorus removal and lower concentration of cations in the effluent. With the return process, the phosphorus removal efficiency was kept higher than 60% until 150 bed volumes; meanwhile, the efficiency without return process became lower than 60% at 25 bed volumes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Phosphorus and nitrogen recycle following algal bio-crude production via continuous hydrothermal liquefaction

DOE PAGES

Edmundson, S.; Huesemann, M.; Kruk, R.; ...

2017-07-25

Phosphorus and nitrogen are essential components of microalgal growth media. Critical to a wide range of biochemical processes, they commonly limit primary productivity. Recycling elemental phosphorus and fixed nitrogen after fuel conversion via hydrothermal liquefaction (HTL) of algae biomass reduces the need for mined phosphorus and synthetic nitrogen resources. We used scenedesmus obliquus DOE 0152.Z and Chlorella sorokiniana DOE1412 as test organisms in assessing nutrient recycle of phosphorus from filtered solids collected downstream of the HTL reactor and nitrogen collected from the aqueous phase after gravimetric biocrude separation. Maximum specific growth rates were measured in growth media using HTL wastemore » as the sole source of either phosphorus or nitrogen and were compared to an algal growth medium control (BG-11). The maximum specific growth rate of both organisms in the recycled phosphorus medium were nearly identical to rates observed in the control medium. Both organisms showed significantly reduced growth rates in the recycled nitrogen medium. C. sorokiniana DOE1412 adapted after several days of exposure whereas S. obliquus DOE0152.Z exhibited poor adaptability to the recycled nitrogen medium. After adaptation, growth rates observed with C. sorokiniana DOE1412 in the recycled nitrogen medium were 3.02 (± 0.13) day -1, 89% of the control medium (3.40 ± 0.21). We further tested maximum specific growth rates of C. sorokiniana DOE1412 in a medium derived entirely from HTL byproducts, completely replacing all components including nitrogen and phosphorus. In this medium we observed rates of 2.70 ± 0.05 day -1, 79% of the control. By adding trace metals to this recycled medium we improved growth rates significantly to 3.10 ± 0.10, 91% of the control, which indicates a critical element is lost in the conversion process. Recycling elemental resources such as phosphorus and nitrogen from the HTL biofuel conversion process can provide a significant

Phosphorus and nitrogen recycle following algal bio-crude production via continuous hydrothermal liquefaction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edmundson, S.; Huesemann, M.; Kruk, R.

Phosphorus and nitrogen are essential components of microalgal growth media. Critical to a wide range of biochemical processes, they commonly limit primary productivity. Recycling elemental phosphorus and fixed nitrogen after fuel conversion via hydrothermal liquefaction (HTL) of algae biomass reduces the need for mined phosphorus and synthetic nitrogen resources. We used scenedesmus obliquus DOE 0152.Z and Chlorella sorokiniana DOE1412 as test organisms in assessing nutrient recycle of phosphorus from filtered solids collected downstream of the HTL reactor and nitrogen collected from the aqueous phase after gravimetric biocrude separation. Maximum specific growth rates were measured in growth media using HTL wastemore » as the sole source of either phosphorus or nitrogen and were compared to an algal growth medium control (BG-11). The maximum specific growth rate of both organisms in the recycled phosphorus medium were nearly identical to rates observed in the control medium. Both organisms showed significantly reduced growth rates in the recycled nitrogen medium. C. sorokiniana DOE1412 adapted after several days of exposure whereas S. obliquus DOE0152.Z exhibited poor adaptability to the recycled nitrogen medium. After adaptation, growth rates observed with C. sorokiniana DOE1412 in the recycled nitrogen medium were 3.02 (± 0.13) day -1, 89% of the control medium (3.40 ± 0.21). We further tested maximum specific growth rates of C. sorokiniana DOE1412 in a medium derived entirely from HTL byproducts, completely replacing all components including nitrogen and phosphorus. In this medium we observed rates of 2.70 ± 0.05 day -1, 79% of the control. By adding trace metals to this recycled medium we improved growth rates significantly to 3.10 ± 0.10, 91% of the control, which indicates a critical element is lost in the conversion process. Recycling elemental resources such as phosphorus and nitrogen from the HTL biofuel conversion process can provide a significant

Vegetarian compared with meat dietary protein source and phosphorus homeostasis in chronic kidney disease.

PubMed

Moe, Sharon M; Zidehsarai, Miriam P; Chambers, Mary A; Jackman, Lisa A; Radcliffe, J Scott; Trevino, Laurie L; Donahue, Susan E; Asplin, John R

2011-02-01

Patients with advanced chronic kidney disease (CKD) are in positive phosphorus balance, but phosphorus levels are maintained in the normal range through phosphaturia induced by increases in fibroblast growth factor-23 (FGF23) and parathyroid hormone (PTH). This provides the rationale for recommendations to restrict dietary phosphate intake to 800 mg/d. However, the protein source of the phosphate may also be important. We conducted a crossover trial in nine patients with a mean estimated GFR of 32 ml/min to directly compare vegetarian and meat diets with equivalent nutrients prepared by clinical research staff. During the last 24 hours of each 7-day diet period, subjects were hospitalized in a research center and urine and blood were frequently monitored. The results indicated that 1 week of a vegetarian diet led to lower serum phosphorus levels and decreased FGF23 levels. The inpatient stay demonstrated similar diurnal variation for blood phosphorus, calcium, PTH, and urine fractional excretion of phosphorus but significant differences between the vegetarian and meat diets. Finally, the 24-hour fractional excretion of phosphorus was highly correlated to a 2-hour fasting urine collection for the vegetarian diet but not the meat diet. In summary, this study demonstrates that the source of protein has a significant effect on phosphorus homeostasis in patients with CKD. Therefore, dietary counseling of patients with CKD must include information on not only the amount of phosphate but also the source of protein from which the phosphate derives.

Two-Dimensional Dirac Fermions Protected by Space-Time Inversion Symmetry in Black Phosphorus

NASA Astrophysics Data System (ADS)

Kim, Jimin; Baik, Seung Su; Jung, Sung Won; Sohn, Yeongsup; Ryu, Sae Hee; Choi, Hyoung Joon; Yang, Bohm-Jung; Kim, Keun Su

2017-12-01

We report the realization of novel symmetry-protected Dirac fermions in a surface-doped two-dimensional (2D) semiconductor, black phosphorus. The widely tunable band gap of black phosphorus by the surface Stark effect is employed to achieve a surprisingly large band inversion up to ˜0.6 eV . High-resolution angle-resolved photoemission spectra directly reveal the pair creation of Dirac points and their movement along the axis of the glide-mirror symmetry. Unlike graphene, the Dirac point of black phosphorus is stable, as protected by space-time inversion symmetry, even in the presence of spin-orbit coupling. Our results establish black phosphorus in the inverted regime as a simple model system of 2D symmetry-protected (topological) Dirac semimetals, offering an unprecedented opportunity for the discovery of 2D Weyl semimetals.

Nitrogen, phosphorus, organic carbon, and biochemical oxygen demand : in Florida surface waters, 1972

USGS Publications Warehouse

Kaufman, Matthew I.; Dysart, J.E.

1978-01-01

Water samples were collected during spring and autumn 1972 from about 100 surface-water sites in Florida. The samples were analyzed for the plant nutrients, nitrogen and phosphorus. In most waters, nitrogen concentrations are less than 2.0 milligrams per liter as nitrogen, and organic nitrogen is dominant. Median total nitrogen concentration for Florida surface waters is between 1.2 and 2.0 milligrams per liter as nitrogen. In samples from 85 percent of the sites, total nitrogen exceeded 0.6 milligrams per liter. Median total phosphorus concentration as phosphorus for Florida surface waters is between 0.05 and 0.1 milligrams per liter. The information will form a base useful to agencies concerned with setting concentration limits for nitrogen and phosphorus in industrial and sewage plant outfalls. (Woodard-USGS)

Managing phosphorus export from golf courses using industrial byproducts as filter materials

USDA-ARS?s Scientific Manuscript database

Golf courses, and in particular the tees, fairways, and putting greens, are vulnerable to loss of phosphorus (P) as dissolved reactive P (DRP) through sandy, porous grass rooting media and subsurface tile drainage. Excess levels of phosphorus (P) in surface waters promotes eutrophication, which in t...

Enhanced capacity of chemically bonded phosphorus/carbon composite as an anode material for potassium-ion batteries

NASA Astrophysics Data System (ADS)

Wu, Xuan; Zhao, Wei; Wang, Hong; Qi, Xiujun; Xing, Zheng; Zhuang, Quanchao; Ju, Zhicheng

2018-02-01

Potassium-ion batteries are attracting great attention as a promising alternative to lithium-ion batteries due to the abundance and low price of potassium. Herein, the phosphorus/carbon composite, obtained by a simple ball-milling of 20 wt% commercial red phosphorus and 80 wt% graphite, is studied as a novel anode for potassium-ion batteries. Considering the high theoretical specific capacity of phosphorus and formation of stable phosphorus-carbon bond, which can alleviate the volume expansion efficiently, the phosphorus/carbon composite exhibits a high charge capacity of 323.5 mA h g-1 after 50 cycles at a current density of 50 mA g-1 with moderate rate capability and cycling stability. By the X-ray diffraction analysis, the alloying-dealloying mechanism of phosphorus is proposed to form a KP phase. Meanwhile, prepotassiation treatment is conducted to improve the low initial coulomb efficiency.

Reactive phosphorus removal from aquaculture and poultry productions systems using polymeric hydrogels.

PubMed

Kofinas, Peter; Kioussis, Dimitri R

2003-01-15

This work reports on the features of a sorption processes for the ultimate removal and recovery of reactive phosphorus from aquaculture and poultry production wastewater effluents. The sorbent used was a cross-linked polyamine (PAA-HCl) polymeric hydrogel. The PAA-HCl hydrogels were prepared by chemically cross-linking aqueous solutions of linear PAA-HCl chains with epichlorohydrin (EPI). The phosphorus binding capacity of the gels was measured in standard aqueous solutions as a function of ionic strength. Equilibrium PO4(3-), loadings of 100 mg anion/g gel were obtained. The regeneration ability of the gels was demonstrated by release of the bound phosphorus anions upon washing with 1-2 M NaOH solution, providing opportunities to recover and reuse the gel over multiple cycles. The ionic polyamine gels have been demonstrated to be appropriate materials for treating poultry and aquaculture wastewater effluents. Upon treatment phosphorus anion concentrations were reduced to levels suitable for discharge into natural surface waters.

Effect of phosphorus deficiency on spectral reflectance and morphology of soybean plants

USGS Publications Warehouse

Milton, N.M.; Eiswerth, B.A.; Ager, C.M.

1991-01-01

Soybean plants were grown in hydroponic solutions having three concentration levels of phosphorus. Spectral reflectance changes included higher reflectance in the green and yellow portions of the electromagnetic spectrum in phosphorus-deficient plants and a difference in position of the long wavelength edge (the red edge) of the chlorophyll absorption band centered near 0.68 ??m. Plants having the least phosphorus in the growing medium did not show the normal shift of the red edge to longer wavelength which occurs as leaves mature. Shoot and root biomass were significantly lower in the phosphorus-deficient plants. These results are consistent with those obtained when soybean plants are dosed with elevated concentrations of metallic elements. We hypothesize that nutrient imbalances or anomalous metal concentrations in the soil set up physiological conditions at the soil/root interface that are responsible for the reflectance differences observed in laboratory and field studies of plants growing in substrates enriched in metallic elements. ?? 1991.

Interspecific competition effects on phosphorus accumulation by Hydrilla verticillata and Vallisneria natans.

PubMed

Zhang, Xiufeng; Liu, Zhengwen

2011-01-01

The competition between submersed plants has been recognized as an important factor influencing the structure of plant communities in shallow lakes. The ability of different species to take up and store nutrients from the surrounding ambience varies, and hence plant community structure might be expected to affect the cycling of nutrients in lake ecosystems. In this study, the uptake of phosphorus by Hydrilla verticillata and Vallisneria natans was studied and compared in monoculture and competitive mixed-culture plantings. Results showed that for both studied species the phosphorus concentrations of different tissues and of whole plants was unaffected by competition. However, the quantity of phosphorus accumulated by whole plants of H. verticillata was significantly higher in mixture culture than in monoculture, while that of V. natans was lower in the mixed culture. The results indicated that H. verticillata has a competitive advantage over V. natans, when the two species are grown in competition, and is able to accumulate a greater quantity of phosphorus.

Black silicon significantly enhances phosphorus diffusion gettering.

PubMed

Pasanen, Toni P; Laine, Hannu S; Vähänissi, Ville; Schön, Jonas; Savin, Hele

2018-01-31

Black silicon (b-Si) is currently being adopted by several fields of technology, and its potential has already been demonstrated in various applications. We show here that the increased surface area of b-Si, which has generally been considered as a drawback e.g. in applications that require efficient surface passivation, can be used as an advantage: it enhances gettering of deleterious metal impurities. We demonstrate experimentally that interstitial iron concentration in intentionally contaminated silicon wafers reduces from 1.7 × 10 13  cm -3 to less than 10 10  cm -3 via b-Si gettering coupled with phosphorus diffusion from a POCl 3 source. Simultaneously, the minority carrier lifetime increases from less than 2 μs of a contaminated wafer to more than 1.5 ms. A series of different low temperature anneals suggests segregation into the phosphorus-doped layer to be the main gettering mechanism, a notion which paves the way of adopting these results into predictive process simulators. This conclusion is supported by simulations which show that the b-Si needles are entirely heavily-doped with phosphorus after a typical POCl 3 diffusion process, promoting iron segregation. Potential benefits of enhanced gettering by b-Si include the possibility to use lower quality silicon in high-efficiency photovoltaic devices.

Phene Synergism between Root Hair Length and Basal Root Growth Angle for Phosphorus Acquisition1[OPEN

PubMed Central

Miguel, Magalhaes Amade

2015-01-01

Shallow basal root growth angle (BRGA) increases phosphorus acquisition efficiency by enhancing topsoil foraging because in most soils, phosphorus is concentrated in the topsoil. Root hair length and density (RHL/D) increase phosphorus acquisition by expanding the soil volume subject to phosphorus depletion through diffusion. We hypothesized that shallow BRGA and large RHL/D are synergetic for phosphorus acquisition, meaning that their combined effect is greater than the sum of their individual effects. To evaluate this hypothesis, phosphorus acquisition in the field in Mozambique was compared among recombinant inbred lines of common bean (Phaseolus vulgaris) having four distinct root phenotypes: long root hairs and shallow basal roots, long root hairs and deep basal roots, short root hairs and shallow basal roots, and short root hairs and deep basal roots. The results revealed substantial synergism between BRGA and RHL/D. Compared with short-haired, deep-rooted phenotypes, long root hairs increased shoot biomass under phosphorus stress by 89%, while shallow roots increased shoot biomass by 58%. Genotypes with both long root hairs and shallow roots had 298% greater biomass accumulation than short-haired, deep-rooted phenotypes. Therefore, the utility of shallow basal roots and long root hairs for phosphorus acquisition in combination is twice as large as their additive effects. We conclude that the anatomical phene of long, dense root hairs and the architectural phene of shallower basal root growth are synergetic for phosphorus acquisition. Phene synergism may be common in plant biology and can have substantial importance for plant fitness, as shown here. PMID:25699587

Fig volatile compounds--a first comparative study.

PubMed

Grison-Pigé, Laure; Hossaert-McKey, Martine; Greeff, Jaco M; Bessière, Jean-Marie

2002-09-01

We analysed the compounds of volatile blends released by receptive figs of twenty Ficus species to attract their specific pollinating wasps. In all, 99 different compounds were identified. The compounds are mainly terpenoids, aliphatic compounds and products from the shikimic acid pathway. In each species blend, there are few major compounds, which are generally common among floral fragrances. Most species blends also include rare compounds, but generally their proportion in the blend is low. A possible basis for species-specificity of Ficus-wasp interactions is discussed in relation to the patterns of volatiles found in this interspecies comparison. Copyright 2002 Elsevier Science Ltd.

Phosphorus vertical migration in aquic brown soil and light chernozem under different phosphorous application rate: a soil column leaching experiment.

PubMed

Zhao, Muqiu; Chen, Xin; Shi, Yi; Zhou, Quanlai; Lu, Caiyan

2009-01-01

A soil column leaching experiment was conducted to study the vertical migration of phosphorus in aquic brown soil and light chernozem under different phosphorus fertilization rates. The results showed that total dissolved phosphorus concentration in the leachates from the two soils was nearly the same, but dissolved inorganic phosphorus concentration was obviously different. In all fertilization treatments, aquic brown soil had a higher content of phosphorus in calcium chloride extracts compared with light chernozem. But Olsen phosphorus content was higher at the soil depth beneath 0-20 cm, and increased with increasing phosphorus application rate.

Multiple myeloma on polycythemia vera following radioactive phosphorus therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

West, W.O.

1976-11-01

A 74-year-old white man with established polycythemia vera was treated with radioactive phosphorus after phlebotomies alone failed to control his disease. About 2/sup 3///sub 4/ years later he died of multiple myeloma. The mutagenic effect of radioactive phosphorus may have caused or possibly accelerated preexisting myeloma. Basic nonmalignant disease deserves careful consideration before radiation or radiomimetic agents are used. One might consider a probably less mutagenic drug such as hydroxyurea in patients with polycythemia vera when phlebotomy alone does not give good control of red cell mass and thrombocytosis.

Neuroelectric brain imaging during a real visit of a fine arts gallery: a neuroaesthetic study of XVII century Dutch painters.

PubMed

Babiloni, F; Cherubino, P; Graziani, I; Trettel, A; Infarinato, F; Picconi, D; Borghini, G; Maglione, A G; Mattia, D; Vecchiato, G

2013-01-01

Neuroaesthetic is a scientific discipline founded more than a decade ago and it refers to the study of the neural bases of beauty perception in art. The aim of this paper is to investigate the neuroelectrical correlates of brain activity of the observation of real paintings showed in a national fine arts gallery (Scuderie del Quirinale) in Rome, Italy. In fact, the present study was designed to examine how motivational factors as indexed by EEG asymmetry over the prefrontal cortex (relative activity of the left and right hemispheres) could be related to the experience of viewing a series of figurative paintings. The fine arts gallery was visited by a group of 25 subjects during an exhibition of the XVII century Dutch painters. Results suggested a strict correlation of the estimated EEG asymmetry with the verbal pleasantness scores reported by the subjects (p<0,05) and an inverse correlation of the perceived pleasantness with the observed painting's surface dimensions (p<0,002).

Photoabsorption study of Bacillus megaterium, DNA and Related Biological Materials in the Phosphorus K-edge Region

NASA Technical Reports Server (NTRS)

Frigo, Sean P.; McNulty,Ian; Richmond, Robert C.; Ehret, Charles F.

2003-01-01

We have measured the x-ray transmission spectra of several biologically related samples in the phosphorus K-edge absorption region. These include red phosphorus, hydrated sodium phosphate (Na3PO4 12 H2O), deoxyribonucleic acid (DNA), adenosinetriphosphate (ATP), diolylphosphatidyl choline (DOPC), and Bacillus megaterium spores. Red phosphorus essentially displays an edge-jump. All other spectra are similar in form and energy position, where each is dominated by a narrower, more intense first peak and a broader but less intense second peak. The corresponding K-edge absorption thresholds are shifted towards higher energy relative to that for red phosphorus, as expected for increasing degrees of phosphorus oxidation. The B.meguterium spectrum has aspects common to both the phosphate and DNA spectra and is therefore interpreted as a composite of spectra arising from DNA/RNA and phosphates within the spore. The B. megaterium spore spectrum provides needed information for resonant radiation damage studies in the phosphorus K-edge absorption region by identifying candidate photoexcitations. In addition, the absorption spectra will be useful in macromolecular crystallography studies employing anomalous dispersion effects at the phosphorus K-edge.

Photoabsorption Study of Bacillus megaterium, DNA and Related Biological Materials in the Phosphorus K-edge Region

NASA Technical Reports Server (NTRS)

Frigo, Sean P.; McNulty, Ian; Richmond, Robert C.; Ehret, Charles F.

2002-01-01

We have measured the x-ray transmission spectra of several biologically related samples in the phosphorus K-edge absorption region. These include elemental red phosphorus, hydrated sodium phosphate (Na3PO4.12H2O), deoxyribonucleic acid (DNA), adenosinetriphosphate (ATP), diolylphosphatidyl choline (DOPC), and Bacillus megaterium spores. Elemental red phosphorus essentially displays an edge-jump. All other spectra are similar in form and energy position. Each spectrum for these substances is dominated by a narrower, more intense first peak and a broader but less intense second peak. The corresponding K-edge absorption thresholds are shifted towards higher energy relative to that for elemental red phosphorus, as expected for increasing degrees of phosphorus oxidation. The B. megaterium spectrum has aspects common to both the phosphate and DNA spectra and is therefore interpreted as a composite of spectra arising from DNA/RNA and phosphates within the spore. The B. megaterium spore spectrum provides needed information for resonant radiation damage studies in the phosphorus K-edge absorption region by identifying candidate photoexcitations. In addition,the absorption spectra will be useful in macromolecular crystallography studies employing anomalous dispersion effects at the phosphorus K-edge.

Phosphorus storage and mobilization in coastal Phragmites wetlands: Influence of local-scale hydrodynamics

NASA Astrophysics Data System (ADS)

Karstens, Svenja; Buczko, Uwe; Glatzel, Stephan

2016-04-01

Coastal Phragmites wetlands are at the interface between terrestrial and aquatic ecosystems and are of paramount importance for nutrient regulation. They can act both as sinks and sources for phosphorus, depending on environmental conditions, sediment properties as well as on antecedent nutrient loading and sorption capacity of the sediments. The Darss-Zingst Bodden Chain is a shallow lagoon system at the German Baltic Sea coast with a long eutrophication history. It is lined almost at its entire length by reed wetlands. In order to elucidate under which conditions these wetlands act as sources or sinks for phosphorus, in-situ data of chemo-physical characteristics of water and sediment samples were combined with hydrodynamic measurements and laboratory experiments. Small-scale basin structures within the wetland serve as sinks for fine-grained particles rich in phosphorus, iron, manganese and organic matter. Without turbulent mixing the bottom water and the sediment surface lack replenishment of oxygen. During stagnant periods with low water level, low turbulence and thus low-oxygen conditions phosphorus from the sediments is released. But the sediments are capable of becoming sinks again once oxygen is resupplied. A thin oxic sediment surface layer rich in iron and manganese adsorbs phosphorus quickly. We demonstrate that sediments in coastal Phragmites wetlands can serve both as sources and sinks of soluble reactive phosphorus on a very short time-scale, depending on local-scale hydrodynamics and the state of the oxic-anoxic sediment interface.

Coral Skeletons Provide Historical Evidence of Phosphorus Runoff on the Great Barrier Reef

PubMed Central

Mallela, Jennie; Lewis, Stephen E.; Croke, Barry

2013-01-01

Recently, the inshore reefs of the Great Barrier Reef have declined rapidly because of deteriorating water quality. Increased catchment runoff is one potential culprit. The impacts of land-use on coral growth and reef health however are largely circumstantial due to limited long-term data on water quality and reef health. Here we use a 60 year coral core record to show that phosphorus contained in the skeletons (P/Ca) of long-lived, near-shore Porites corals on the Great Barrier Reef correlates with annual records of fertiliser application and particulate phosphorus loads in the adjacent catchment. Skeletal P/Ca also correlates with Ba/Ca, a proxy for fluvial sediment loading, again linking near-shore phosphorus records with river runoff. Coral core records suggest that phosphorus levels increased 8 fold between 1949 and 2008 with the greatest levels coinciding with periods of high fertiliser-phosphorus use. Periods of high P/Ca correspond with intense agricultural activity and increased fertiliser application in the river catchment following agricultural expansion and replanting after cyclone damage. Our results demonstrate how coral P/Ca records can be used to assess terrestrial nutrient loading of vulnerable near-shore reefs. PMID:24086606

Black phosphorus-monolayer MoS2 van der Waals heterojunction p-n diode.

PubMed

Deng, Yexin; Luo, Zhe; Conrad, Nathan J; Liu, Han; Gong, Yongji; Najmaei, Sina; Ajayan, Pulickel M; Lou, Jun; Xu, Xianfan; Ye, Peide D

2014-08-26

Phosphorene, a elemental 2D material, which is the monolayer of black phosphorus, has been mechanically exfoliated recently. In its bulk form, black phosphorus shows high carrier mobility (∼10,000 cm(2)/V·s) and a ∼0.3 eV direct band gap. Well-behaved p-type field-effect transistors with mobilities of up to 1000 cm(2)/V·s, as well as phototransistors, have been demonstrated on few-layer black phosphorus, showing its promise for electronics and optoelectronics applications due to its high hole mobility and thickness-dependent direct band gap. However, p–n junctions, the basic building blocks of modern electronic and optoelectronic devices, have not yet been realized based on black phosphorus. In this paper, we demonstrate a gate-tunable p–n diode based on a p-type black phosphorus/n-type monolayer MoS2 van der Waals p–n heterojunction. Upon illumination, these ultrathin p–n diodes show a maximum photodetection responsivity of 418 mA/W at the wavelength of 633 nm and photovoltaic energy conversion with an external quantum efficiency of 0.3%. These p–n diodes show promise for broad-band photodetection and solar energy harvesting.

Understanding of polyhydroxybutyrate production under carbon and phosphorus-limited growth conditions in non-axenic continuous culture.

PubMed

Cavaillé, Laëtitia; Albuquerque, Maria; Grousseau, Estelle; Lepeuple, Anne-Sophie; Uribelarrea, Jean-Louis; Hernandez-Raquet, Guillermina; Paul, Etienne

2016-02-01

In a waste into resource strategy, a selection of polyhydroxybutyrate (PHB)-accumulating organisms from activated sludge was achieved in an open continuous culture under acetic acid and phosphorus limitation. Once the microbial population was selected at a dilution rate (D), an increase in phosphorus limitation degree was applied in order to study the intracellular phosphorus plasticity of selected bacteria and the resulting capacity to produce PHB. Whatever D, all selected populations were able to produce PHB. At a D, the phosphorus availability determined the phosphorus-cell content which in turn fixed the amount of cell. All the remaining carbon was thus directed toward PHB. By decreasing D, microorganisms adapted more easily to higher phosphorus limitation leading to higher PHB content. A one-stage continuous reactor operated at D=0.023h(-)(1) gave reliable high PHB productivity with PHB content up to 80%. A two-stage reactor could ensure better productivity while allowing tuning product quality. Copyright © 2015 Elsevier Ltd. All rights reserved.

Vegetarian Compared with Meat Dietary Protein Source and Phosphorus Homeostasis in Chronic Kidney Disease

PubMed Central

Zidehsarai, Miriam P.; Chambers, Mary A.; Jackman, Lisa A.; Radcliffe, J. Scott; Trevino, Laurie L.; Donahue, Susan E.; Asplin, John R.

2011-01-01

Summary Background and objectives Patients with advanced chronic kidney disease (CKD) are in positive phosphorus balance, but phosphorus levels are maintained in the normal range through phosphaturia induced by increases in fibroblast growth factor-23 (FGF23) and parathyroid hormone (PTH). This provides the rationale for recommendations to restrict dietary phosphate intake to 800 mg/d. However, the protein source of the phosphate may also be important. Design, setting, participants, & measurements We conducted a crossover trial in nine patients with a mean estimated GFR of 32 ml/min to directly compare vegetarian and meat diets with equivalent nutrients prepared by clinical research staff. During the last 24 hours of each 7-day diet period, subjects were hospitalized in a research center and urine and blood were frequently monitored. Results The results indicated that 1 week of a vegetarian diet led to lower serum phosphorus levels and decreased FGF23 levels. The inpatient stay demonstrated similar diurnal variation for blood phosphorus, calcium, PTH, and urine fractional excretion of phosphorus but significant differences between the vegetarian and meat diets. Finally, the 24-hour fractional excretion of phosphorus was highly correlated to a 2-hour fasting urine collection for the vegetarian diet but not the meat diet. Conclusions In summary, this study demonstrates that the source of protein has a significant effect on phosphorus homeostasis in patients with CKD. Therefore, dietary counseling of patients with CKD must include information on not only the amount of phosphate but also the source of protein from which the phosphate derives. PMID:21183586

Interactions between calcium and phosphorus in the regulation of the production of fibroblast growth factor 23 in vivo

PubMed Central

Quinn, Stephen J.; Thomsen, Alex R. B.; Pang, Jian L.; Kantham, Lakshmi; Bräuner-Osborne, Hans; Pollak, Martin; Goltzman, David

2013-01-01

Calcium and phosphorus homeostasis are highly interrelated and share common regulatory hormones, including FGF23. However, little is known about calcium's role in the regulation of FGF23. We sought to investigate the regulatory roles of calcium and phosphorus in FGF23 production using genetic mouse models with targeted inactivation of PTH (PTH KO) or both PTH and the calcium-sensing receptor (CaSR; PTH-CaSR DKO). In wild-type, PTH KO, and PTH-CaSR DKO mice, elevation of either serum calcium or phosphorus by intraperitoneal injection increased serum FGF23 levels. In PTH KO and PTH-CaSR DKO mice, however, increases in serum phosphorus by dietary manipulation were accompanied by severe hypocalcemia, which appeared to blunt stimulation of FGF23 release. Increases in dietary phosphorus in PTH-CaSR DKO mice markedly decreased serum 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] despite no change in FGF23, suggesting direct regulation of 1,25(OH)2D3 synthesis by serum phosphorus. Calcium-mediated increases in serum FGF23 required a threshold level of serum phosphorus of about 5 mg/dl. Analogously, phosphorus-elicited increases in FGF23 were markedly blunted if serum calcium was less than 8 mg/dl. The best correlation between calcium and phosphorus and serum FGF23 was found between FGF23 and the calcium × phosphorus product. Since calcium stimulated FGF23 production in the PTH-CaSR DKO mice, this effect cannot be mediated by the full-length CaSR. Thus the regulation of FGF23 by both calcium and phosphorus appears to be fundamentally important in coordinating the serum levels of both mineral ions and ensuring that the calcium × phosphorus product remains within a physiological range. PMID:23233539

Phosphorus recovery as struvite from eutropic waters by XDA-7 resin.

PubMed

Li, Huanwen; Ye, Zhiping; Lin, Ying; Wang, Fengying

2012-01-01

Phosphorus releases into aquatic environment and its subsequent contribution to eutrophication have resulted in a widespread global pollution issue. However, phosphorus is a non-renewable source. The potential supplies of phosphorus are decreasing worldwide. Therefore, removal and recovery of phosphorus from the eutropic waters is important, emergent and necessary. In this research, experiments for recovering phosphate from eutropic waters by anion exchange combined with struvite precipitation were conducted. The results indicated that the prepared XDA-7 resin was an effective adsorbent for phosphate. The adsorption isotherm of XDA-7 resin was found to be a modified Freundlich type. The maximum phosphate adsorption (20.9 mg/g) occurred in the pH range of 6.0-8.0. Phosphate adsorbed on the XDA-7 resin was effectively desorbed with 8% NaCl solution, and the resin was able to be regenerated with 3% NaClO and 4% NaOH solutions. Phosphate desorbed from the resin was recovered as magnesium ammonium phosphate (struvite). The obtained struvite was analyzed by acid dissolution method, scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). The struvite precipitate was found to be 75.8% in purity, a high-value fertilizer.

Plasmonic Properties of Silicon Nanocrystals Doped with Boron and Phosphorus.

PubMed

Kramer, Nicolaas J; Schramke, Katelyn S; Kortshagen, Uwe R

2015-08-12

Degenerately doped silicon nanocrystals are appealing plasmonic materials due to silicon's low cost and low toxicity. While surface plasmonic resonances of boron-doped and phosphorus-doped silicon nanocrystals were recently observed, there currently is poor understanding of the effect of surface conditions on their plasmonic behavior. Here, we demonstrate that phosphorus-doped silicon nanocrystals exhibit a plasmon resonance immediately after their synthesis but may lose their plasmonic response with oxidation. In contrast, boron-doped nanocrystals initially do not exhibit plasmonic response but become plasmonically active through postsynthesis oxidation or annealing. We interpret these results in terms of substitutional doping being the dominant doping mechanism for phosphorus-doped silicon nanocrystals, with oxidation-induced defects trapping free electrons. The behavior of boron-doped silicon nanocrystals is more consistent with a strong contribution of surface doping. Importantly, boron-doped silicon nanocrystals exhibit air-stable plasmonic behavior over periods of more than a year.

Nitrogen and phosphorus removal in pilot-scale anaerobic-anoxic oxidation ditch system.

PubMed

Peng, Yongzhen; Hou, Hongxun; Wang, Shuying; Cui, Youwei; Zhiguo, Yuan

2008-01-01

To achieve high efficiency of nitrogen and phosphorus removal and to investigate the rule of simultaneous nitrification and denitrification phosphorus removal (SNDPR), a whole course of SNDPR damage and recovery was studied in a pilot-scale, anaerobic-anoxic oxidation ditch (OD), where the volumes of anaerobic zone, anoxic zone, and ditches zone of the OD system were 7, 21, and 280 L, respectively. The reactor was fed with municipal wastewater with a flow rate of 336 L/d. The concept of simultaneous nitrification and denitrification (SND) rate (r(SND)) was put forward to quantify SND. The results indicate that: (1) high nitrogen and phosphorus removal efficiencies were achieved during the stable SND phase, total nitrogen (TN) and total phosphate (TP) removal rates were 80% and 85%, respectively; (2) when the system was aerated excessively, the stability of SND was damaged, and r(SND) dropped from 80% to 20% or less; (3) the natural logarithm of the ratio of NO(x) to NH4+ in the effluent had a linear correlation to oxidation-reduction potential (ORP); (4) when NO3- was less than 6 mg/L, high phosphorus removal efficiency could be achieved; (5) denitrifying phosphorus removal (DNPR) could take place in the anaerobic-anoxic OD system. The major innovation was that the SND rate was devised and quantified.

Effects of conservation practices on phosphorus loss reduction from an Indiana agricultural watershed

USDA-ARS?s Scientific Manuscript database

Phosphorus losses from agricultural lands have caused serious eutrophication problems, particularly in Lake Erie. However, techniques that can effectively reduce total and soluble phosphorus losses from croplands and drainage channels can be difficult to implement and gauge. This modeling study was ...

Phosphorus removal from aqueous solution in parent and aluminum-modified eggshells: thermodynamics and kinetics, adsorption mechanism, and diffusion process.

PubMed

Guo, Ziyan; Li, Jiuhai; Guo, Zhaobing; Guo, Qingjun; Zhu, Bin

2017-06-01

Parent and aluminum-modified eggshells were prepared and characterized with X-ray diffraction, specific surface area measurements, infrared spectroscopy, zeta potential, and scanning electron microscope, respectively. Besides, phosphorus adsorptions in these two eggshells at different temperatures and solution pH were carried out to study adsorption thermodynamics and kinetics as well as the mechanisms of phosphorus adsorption and diffusion. The results indicated that high temperature was favorable for phosphorus adsorption in parent and aluminum-modified eggshells. Alkaline solution prompted phosphorus adsorption in parent eggshell, while the maximum adsorption amount was achievable at pH 4 in aluminum-modified eggshell. Adsorption isotherms of phosphorus in these eggshells could be well described by Langmuir and Freundlich models. Phosphorus adsorption amounts in aluminum-modified eggshell were markedly higher compared to those in parent eggshell. Adsorption heat indicated that phosphorus adsorption in parent eggshell was a typically physical adsorption process, while chemical adsorption mechanism of ion exchange between phosphorus and hydroxyl groups on the surface of eggshells was dominated in aluminum-modified eggshell. The time-resolved uptake curves showed phosphorus adsorption in aluminum-modified eggshell was significantly faster than that in parent eggshell. Moreover, there existed two clear steps in time-resolved uptake curves of phosphorus in parent eggshell. Based on pseudo-second order kinetic model and intraparticle diffusion model, we inferred more than one process affected phosphorus adsorption. The first process was the diffusion of phosphorus through water to external surface and the opening of pore channel in the eggshells, and the second process was mainly related to intraparticle diffusion.

Nucleophilic substitution at phosphorus centers (SN2@p).

PubMed

van Bochove, Marc A; Swart, Marcel; Bickelhaupt, F Matthias

2007-12-03

We have studied the characteristics of archetypal model systems for bimolecular nucleophilic substitution at phosphorus (SN2@P) and, for comparison, at carbon (SN2@C) and silicon (SN2@Si) centers. In our studies, we applied the generalized gradient approximation (GGA) of density functional theory (DFT) at the OLYP/TZ2P level. Our model systems cover nucleophilic substitution at carbon in X(-)+CH3Y (SN2@C), at silicon in X(-)+SiH3Y (SN2@Si), at tricoordinate phosphorus in X(-)+PH2Y (SN2@P3), and at tetracoordinate phosphorus in X(-)+POH2Y (SN2@P4). The main feature of going from SN2@C to SN2@P is the loss of the characteristic double-well potential energy surface (PES) involving a transition state [X--CH3--Y]- and the occurrence of a single-well PES with a stable transition complex, namely, [X--PH2--Y]- or [X--POH2--Y](-). The differences between SN2@P3 and SN2@P4 are relatively small. We explored both the symmetric and asymmetric (i.e. X, Y=Cl, OH) SN2 reactions in our model systems, the competition between backside and frontside pathways, and the dependence of the reactions on the conformation of the reactants. Furthermore, we studied the effect, on the symmetric and asymmetric SN2@P3 and S(N)2@P4 reactions, of replacing hydrogen substituents at the phosphorus centers by chlorine and fluorine in the model systems X(-)+PR2Y and X(-)+POR2Y, with R=Cl, F. An interesting phenomenon is the occurrence of a triple-well PES not only in the symmetric, but also in the asymmetric SN2@P4 reactions of X(-)+POCl2--Y.

Effect of phosphorus addition on the reductive transformation of pentachlorophenol (PCP) and iron reduction with microorganism involvement.

PubMed

Wang, Yongkui; Liu, Xianli; Huang, Jiexun; Xiao, Wensheng; Zhang, Jiaquan; Yin, Chunqin

2017-10-01

The transformation of phosphorus added to the soil environment has been proven to be influenced by the Fe biochemical process, which thereby may affect the transformation of organic chlorinated contaminants. However, the amount of related literatures regarding this topic is limited. This study aimed to determine the effects of phosphorus addition on pentachlorophenol (PCP) anaerobic transformation, iron reduction, and paddy soil microbial community structure. Results showed that the transformation of phosphorus, iron, and PCP were closely related to the microorganisms. Moreover, phosphorus addition significantly influenced PCP transformation and iron reduction, which promoted and inhibited these processes at low and high concentrations, respectively. Both the maximum reaction rate of PCP transformation and the maximum Fe(II) amount produced were obtained at 1 mmol/L phosphorus concentration. Among the various phosphorus species, dissolved P and NaOH-P considerably changed, whereas only slight changes were observed for the remaining phosphorus species. Microbial community structure analysis demonstrated that adding low concentration of phosphorus promoted the growth of Clostridium bowmanii, Clostridium hungatei, and Clostridium intestinale and Pseudomonas veronii. By contrast, high-concentration phosphorus inhibited growth of these microorganisms, similar to the curves of PCP transformation and iron reduction. These observations indicated that Clostridium and P. veronii, especially Clostridium, played a vital role in the transformation of related substances in the system. All these findings may serve as a reference for the complicated reactions among the multiple components of soils.

[Release and supplement of carbon, nitrogen and phosphorus from jellyfish (Nemopilema nomurai) decomposition in seawater].

PubMed

Qu, Chang-feng; Song, Jin-ming; Li, Ning; Li, Xue-gang; Yuan, Hua-mao; Duan, Li-qin

2016-01-01

Abstract: Jellyfish bloom has been increasing in Chinese seas and decomposition after jellyfish bloom has great influences on marine ecological environment. We conducted the incubation of Nemopilema nomurai decomposing to evaluate its effect on carbon, nitrogen and phosphorus recycling of water column by simulated experiments. The results showed that the processes of jellyfish decomposing represented a fast release of biogenic elements, and the release of carbon, nitrogen and phosphorus reached the maximum at the beginning of jellyfish decomposing. The release of biogenic elements from jellyfish decomposition was dominated by dissolved matter, which had a much higher level than particulate matter. The highest net release rates of dissolved organic carbon and particulate organic carbon reached (103.77 ± 12.60) and (1.52 ± 0.37) mg · kg⁻¹ · h⁻¹, respectively. The dissolved nitrogen was dominated by NH₄⁺-N during the whole incubation time, accounting for 69.6%-91.6% of total dissolved nitrogen, whereas the dissolved phosphorus was dominated by dissolved organic phosphorus during the initial stage of decomposition, being 63.9%-86.7% of total dissolved phosphorus and dominated by PO₄³⁻-P during the late stage of decomposition, being 50.4%-60.2%. On the contrary, the particulate nitrogen was mainly in particulate organic nitrogen, accounting for (88.6 ± 6.9) % of total particulate nitrogen, whereas the particulate phosphorus was mainly in particulate. inorganic phosphorus, accounting for (73.9 ±10.5) % of total particulate phosphorus. In addition, jellyfish decomposition decreased the C/N and increased the N/P of water column. These indicated that jellyfish decomposition could result in relative high carbon and nitrogen loads.

Development of a biologically based fertilizer, incorporating Bacillus megaterium A6, for improved phosphorus nutrition of oilseed rape.

PubMed

Hu, Xiaojia; Roberts, Daniel P; Xie, Lihua; Maul, Jude E; Yu, Changbing; Li, Yinshui; Zhang, Shujie; Liao, Xing

2013-04-01

Sustainable methods with diminished impact on the environment need to be developed for the production of oilseed rape in China and other regions of the world. A biological fertilizer consisting of Bacillus megaterium A6 cultured on oilseed rape meal improved oilseed rape seed yield (P < 0.0001) relative to the nontreated control in 2 greenhouse pot experiments using natural soil. This treatment resulted in slightly greater yield than oilseed rape meal without strain A6 in 1 of 2 experiments, suggesting a role for strain A6 in improving yield. Strain A6 was capable of solubilizing phosphorus from rock phosphate in liquid culture and produced enzymes capable of mineralizing organic phosphorus (acid phosphatase, phytase) in liquid culture and in the biological fertilizer. The biologically based fertilizer, containing strain A6, improved plant phosphorus nutrition in greenhouse pot experiments resulting in significantly greater available phosphorus in natural soil and in significantly greater plant phosphorus content relative to the nontreated control. Seed yield and available phosphorus in natural soil were significantly greater with a synthetic chemical fertilizer treatment, reduced in phosphorus content, than the biological fertilizer treatment, but a treatment containing the biological fertilizer combined with the synthetic fertilizer provided the significantly greatest seed yield, available phosphorus in natural soil, and plant phosphorus content. These results suggest that the biological fertilizer was capable of improving oilseed rape seed yield, at least in part, through the phosphorus-solubilizing activity of B. megaterium A6.

The impact of processing meat and fish products on phosphorus intake in chronic kidney disease patients.

PubMed

Lou-Arnal, Luis M; Caverni-Muñoz, Alberto; Arnaudas-Casanova, Laura; Vercet-Tormo, Antonio; Gimeno-Orna, José A; Sanz-París, Alejandro; Caramelo-Gutiérrez, Rocío; Alvarez-Lipe, Rafael; Sahdalá-Santana, Laura; Gracia-García, Olga; Luzón-Alonso, Marta

2013-11-13

The use of phosphate additives in meat and fish processing leads to a phosphorus overload that we cannot quantify through labelling or food composition tables. We analysed this increase by measuring phosphorus content in these products by spectrophotometry. We determined the phosphorus/protein ratio in fresh meat and fish products with varying degrees of processing by spectrophotometry (phosphorus) and the Kjeldahl method (proteins). We contrasted these results with those reflected in the food composition tables. The phosphorus/protein ratio was higher in processed meat products (15.83 mg/g) than in battered (11.04 mg/g) and frozen meat products (10.5mg/g), and was lower in fresh (8.41 mg/g) and refrigerated meat products (8.78 mg/g). Fresh white fish had a phosphorus/protein ratio of 8.58mg/g, while it increased by 22% (10.3mg/g) in frozen white fish and by 46% (12.54 mg/g) in battered fish. The information in the tables was poor and confusing, and no reference is made to the brands tested. Processing meat and fish products poses a serious obstacle to the reduction of phosphorus intake. The current regulatory framework does not assist us in the objective of reducing phosphorus additives, since it considers them safe for public consumption. Overcoming these barriers requires a coordinated effort to demonstrate that a high intake of these additives may be harmful to the general population and it should be more closely examined by regulators.

Land-use impact on selected forms of arsenic and phosphorus in soils of different functions

NASA Astrophysics Data System (ADS)

Plak, Andrzej; Bartmiński, Piotr; Dębicki, Ryszard

2017-10-01

The aim of the study was to assess the impact of technosols and geomechanically unchanged soils of the Lublin agglomeration on the concentrations of arsenic and phosphorus, and on selected forms of these elements. Arsenic and phosphorus concentrations were determined in the urban soils of Lublin (Poland), and the relationship between their degree of contamination and different types of land use was estimated. The samples collected were subjected to sequential analysis, using ammonium sulphate, acid ammonium phosphate, oxalate buffer (also with ascorbic acid) and aqua regia for arsenic, and ammonium chloride, sodium hydroxide, hydrochloric acid and aqua regia for phosphorus. The influence of the land use forms was observed in the study. The greatest amount of arsenic (19.62 mg kg-1) was found in the industrial soils of Lublin, while the greatest amount of phosphorus (580.4 mg kg-1) was observed in non-anthropogenic soils (mainly due to the natural accumulation processes of this element). Fractions of arsenic and phosphorus obtained during analysis showed strong differentiation. Amorphic and crystalline fractions of arsenic, bound with iron oxides, proved to have the highest share in the total arsenic pool. The same situation was noted for phosphorus.

An evaluation of the phosphorus storage capacity of an anaerobic/aerobic sequential batch biofilm reactor.

PubMed

Chiou, Ren-Jie; Yang, Yi-Rong

2008-07-01

The aim of this work was to assess the phosphorus storage capability of the polyphosphate (poly-P) accumulating organisms (PAO) in the biofilm using a sequential batch biofilm reactor (SBBR). In the anaerobic phase, the specific COD uptake rates increases from 0.05 to 0.22 (mg-COD/mg-biomass/h) as the initial COD increases and the main COD uptake activity occurs in the initial 30 min. The polyhydroxyalkanoates (PHAs) accumulation from 18 to 38 (mg-PHA/g-biomass) and phosphorus release from 20 to 60 (mg-P/L) share a similar trend. The adsorbed COD cannot be immediately transformed to PHAs. Since the PHAs' demand per released phosphorus is independent of the initial COD, the enhancement of the PHA accumulation would be of benefit to phosphorus release. The only requirement is to have an initial amount of substrate that will result in sufficient PHA accumulation (approximately 20 mg-PHA/g-biomass) for phosphorus release. During the aerobic phase, the aeration should not only provide sufficient dissolved oxygen, but should also enhance the mass transfer and the diffusion. In other words, the limitation to the phosphorus storage capability always occurs during the anaerobic phase, not the aerobic phase.

Investigation of nitrogen and phosphorus contents in water in the tributaries of Danjiangkou Reservoir

PubMed Central

Liu, Yan; Zhu, Yuanyuan; Qiao, Xiaocui; Chang, Sheng; Fu, Qing

2018-01-01

As part of the efforts to ensure adequate supply of quality water from Danjiangkou Reservoir to Beijing, surface water samples were taken from the tributaries of Danjiangkou Reservoir in the normal (May), flood (August) and dry (December) seasons of 2014, and characterized for nitrogen and phosphorus contents as specified in the applicable standards. Test results indicated that (i) the organic pollution in the Sihe and Shendinghe rivers was more serious than those in other tributaries, and the concentrations of nitrogen and phosphorus favoured the growth of most algae; (ii) total phosphorus (TP), total nitrogen (TN) and dissolved inorganic nitrogen (DIN) were in the forms of dissolved phosphorus (DTP), dissolved nitrogen (DTN) and nitrate nitrogen (NO3−-N), respectively, in these seasons; (iii) compared with nitrogen, phosphorus was more likely to block an overrun of phytoplankton; (iv) TN, TP, permanganate index (CODMn) and other ions were positively correlated. These findings are helpful for the government to develop effective measures to protect the source water in Danjingkou Reservoir from pollution. PMID:29410793

ENZYME DEGRADATION OF CHIRAL ORGANIC PHOSPHORUS INSECTICIDES

EPA Science Inventory

Chiral organic phosphorus pesticides (OPs) are expected to be biologically degraded enantioselectively by endogenous enzymes. Various chiral Ops were treated with the enzyme phosphotriesterase (PTE) obtained from partially purified extracts of Escherichia coli strain DH-5- carryi...

Reactive-transport simulation of phosphorus in the sewage plume at the Massachusetts Military Reservation, Cape Cod, Massachusetts

USGS Publications Warehouse

Parkhurst, David L.; Stollenwerk, Kenneth G.; Colman, John A.

2003-01-01

The subsurface transport of phosphorus introduced by the disposal of treated sewage effluent to ground-infiltration disposal beds at the Massachusetts Military Reservation on western Cape Cod was simulated with a three-dimensional reactive-transport model. The simulations were used to estimate the load of phosphorus transported to Ashumet Pond during operation of the sewage-treatment plant?from 1936 to 1995?and for 60 years following cessation of sewage disposal. The model accounted for spatial and temporal changes in water discharge from the sewage-treatment plant, ground-water flow, transport of associated chemical constituents, and a set of chemical reactions, including phosphorus sorption on aquifer materials, dissolution and precipitation of iron- and manganese-oxyhydroxide and iron phosphate minerals, organic carbon sorption and decomposition, cation sorption, and irreversible denitrification. The flow and transport in the aquifer were simulated by using parameters consistent with those used in previous flow models of this area of Cape Cod, except that numerical dispersion was much larger than the physical dispersion estimated in previous studies. Sorption parameters were fit to data derived from phosphorus sorption and desorption laboratory column experiments. Rates of organic carbon decomposition were adjusted to match the location of iron concentrations in an anoxic iron zone within the sewage plume. The sensitivity of the simulated load of phosphorus transported to Ashumet Pond was calculated for a variety of processes and input parameters. Model limitations included large uncertainties associated with the loading of the sewage beds, the flow system, and the chemistry and sorption characteristics in the aquifer. The results of current model simulations indicate a small load of phosphorus transported to Ashumet Pond during 1965?85, but this small load was particularly sensitive to model parameters that specify flow conditions and the chemical process by

Evaluating the efficiency of carbon utilisation via bioenergetics between biological aerobic and denitrifying phosphorus removal systems

PubMed Central

Jin, Zhan; He, Yin; Xu, Xuan; Zheng, Xiang-yong

2017-01-01

There are two biological systems available for removing phosphorus from waste water, conventional phosphorus removal (CPR) and denitrifying phosphorus removal (DPR) systems, and each is characterized by the type of sludge used in the process. In this study, we compared the characteristics associated with the efficiency of carbon utilization between CPR and DPR sludge using acetate as a carbon source. For DPR sludge, the heat emitted during the phosphorus release and phosphorus uptake processes were 45.79 kJ/mol e- and 84.09 kJ/mol e-, respectively. These values were about 2 fold higher than the corresponding values obtained for CPR sludge, suggesting that much of the energy obtained from the carbon source was emitted as heat. Further study revealed a smaller microbial mass within the DPR sludge compared to CPR sludge, as shown by a lower sludge yield coefficient (0.05 gVSS/g COD versus 0.36 gVSS/g COD), a result that was due to the lower energy capturing efficiency of DPR sludge according to bioenergetic analysis. Although the efficiency of anoxic phosphorus removal was only 39% the efficiency of aerobic phosphorus removal, the consumption of carbon by DPR sludge was reduced by 27.8% compared to CPR sludge through the coupling of denitrification with dephosphatation. PMID:29065157

Potential phosphorus eutrophication mitigation strategy: Biochar carbon composition, thermal stability and pH influence phosphorus sorption

Treesearch

L.W. Ngatia; Y.P. Hsieh; D. Nemours; R. Fu; R.W. Taylor

2017-01-01

Phosphorus (P) eutrophication is a major pollution problem globally, with unprecedented amount of P emanating from agricultural sources. But little is known about the optimization of soil-biochar P sorption capacity. The study objective was to determine how biochar feedstocks and pyrolysis conditions influences carbon (C) thermal stability, C composition and pH and in...

Phosphorus Concentrations, Loads, and Yields in the Illinois River Basin, Arkansas and Oklahoma, 2000-2004

USGS Publications Warehouse

Tortorelli, Robert L.; Pickup, Barbara E.

2006-01-01

The Illinois River and tributaries, Flint Creek and Baron Fork, are designated scenic rivers in Oklahoma. Recent phosphorus levels in streams in the basin have resulted in the growth of excess algae, which have limited the aesthetic benefits of water bodies in the basin, especially the Illinois River and Lake Tenkiller. The Oklahoma Water Resources Board has established a standard for total phosphorus not to exceed the 30-day geometric mean concentration of 0.037 milligram per liter in Oklahoma Scenic Rivers. The U.S. Geological Survey, in cooperation with the Oklahoma Water Resources Board, conducted an investigation to summarize phosphorus concentrations and provide estimates of phosphorus loads, yields, and flow-weighted concentrations in the Illinois River and tributaries from January 2000 through December 2004. Data from water-quality samples collected from 2000 to 2004 were used to summarize phosphorus concentrations and estimate phosphorus loads, yields, and mean flow-weighted concentrations in the Illinois River basin for three 3-year periods - 2000-2002, 2001-2003, and 2002-2004, to update a previous report that used data from water-quality samples from 1997 to 2001. This report provides information needed to advance knowledge of the regional hydrologic system and understanding of hydrologic processes, and provides hydrologic data and results useful to multiple parties for interstate compacts. Phosphorus concentrations in the Illinois River basin were significantly greater in runoff samples than in base-flow samples. Phosphorus concentrations generally decreased with increasing base flow, from dilution, and decreased in the downstream direction in the Illinois River from the Watts to Tahlequah stations. Phosphorus concentrations generally increased with runoff, possibly because of phosphorus resuspension, stream bank erosion, and the addition of phosphorus from nonpoint sources. Estimated mean annual phosphorus loads were greater at the Illinois River

Phosphorus in a ground-water contaminant plume discharging to Ashumet Pond, Cape Cod, Massachusetts, 1999

USGS Publications Warehouse

McCobb, Timothy D.; LeBlanc, Denis R.; Walter, Donald A.; Hess, Kathryn M.; Kent, Douglas B.; Smith, Richard L.

2003-01-01

The discharge of a plume of sewagecontaminated ground water emanating from the Massachusetts Military Reservation to Ashumet Pond on Cape Cod, Massachusetts, has caused concern about excessive loading of nutrients, particularly phosphorus, to the pond. The U.S. Air Force is considering remedial actions to mitigate potentially adverse effects on the ecological characteristics of the pond from continued phosphorus loading. Concentrations as great as 3 milligrams per liter of dissolved phosphorus (as P) are in ground water near the pond's shoreline; concentrations greater than 5 milligrams per liter of phosphorus are in ground water farther upgradient. Temporary drive-point wells were used to collect water samples from 2 feet below the pond bottom to delineate concentration distributions in the pore waters of the pond-bottom sediments. Measurements in the field of specific conductance and colorimetrically determined orthophosphate concentrations provided real-time data to guide the sampling. The contaminant plume discharges to the Fishermans Cove area of Ashumet Pond as evidenced by elevated levels of specific conductance and boron, which are chemically conservative indicators of the sewage-contaminated ground water. Concentrations of nonconservative species, such as dissolved phosphorus, manganese, nitrate, and ammonium, also were elevated above background levels in ground water discharging to the pond, but in spatially complex distributions that reflect their distributions in ground water upgradient of the pond. Phosphorus concentrations exceeded background levels (greater than 0.10 milligram per liter) in the pond-bottom pore water along 875 feet of shoreline. Greatest concentrations (greater than 2 milligrams per liter) occurred within 30 feet of the shore in an area about 225 feet long. Calculations of phosphorus flux in the aquifer upgradient of Ashumet Pond, as determined from water-flux estimates from a steady-state ground-water-flow model and phosphorus

Intensified nitrate and phosphorus removal in an electrolysis -integrated horizontal subsurface-flow constructed wetland.

PubMed

Gao, Y; Xie, Y W; Zhang, Q; Wang, A L; Yu, Y X; Yang, L Y

2017-01-01

A novel electrolysis-integrated horizontal subsurface-flow constructed wetland system (E-HFCWs) was developed for intensified removal of nitrogen and phosphorus contaminated water. The dynamics of nitrogen and phosphorus removal and that of main water qualities of inflow and outflow were also evaluated. The hydraulic retention time (HRT) greatly enhanced nitrate removal when the electrolysis current intensity was stabilized at 0.07 mA/cm 2 . When the HRT ranged from 2 h to 12 h, the removal rate of nitrate increased from 20% to 84%. Phosphorus (P) removal was also greatly enhanced-exceeding 90% when the HRT was longer than 4 h in the electrolysis-integrated HFCWs. This improved P removal is due to the in-situ formation of ferric ions by anodizing of sacrificial iron anodes, causing chemical precipitation, physical adsorption and flocculation of phosphorus. Thus, electrolysis plays an important role in nitrate and phosphorus removal. The diversity and communities of bacteria in the biofilm of substrate was established by the analysis of 16S rDNA gene sequences, and the biofilm was abundant with Comamonadaceae and Xanthomonadaceae bacteria in E-HFCWs. Test results illustrated that the electrolysis integrated with horizontal subsurface-flow constructed wetland is a feasible and effective technology for intensified nitrogen and phosphorus removal. Copyright © 2016. Published by Elsevier Ltd.

Enhanced biological phosphorus removal with different carbon sources.

PubMed

Shen, Nan; Zhou, Yan

2016-06-01

Enhanced biological phosphorus removal (EBPR) process is one of the most economical and sustainable methods for phosphorus removal from wastewater. However, the performance of EBPR can be affected by available carbon sources types in the wastewater that may induce different functional microbial communities in the process. Glycogen accumulating organisms (GAOs) and polyphosphate accumulating organisms (PAOs) are commonly found by coexisting in the EBPR process. Predominance of GAO population may lead to EBPR failure due to the competition on carbon source with PAO without contributing phosphorus removal. Carbon sources indeed play an important role in alteration of PAOs and GAOs in EBPR processes. Various types of carbon sources have been investigated for EBPR performance. Certain carbon sources tend to enrich specific groups of GAOs and/or PAOs. This review summarizes the types of carbon sources applied in EBPR systems and highlights the roles of these carbon sources in PAO and GAO competition. Both single (e.g., acetate, propionate, glucose, ethanol, and amino acid) and complex carbon sources (e.g., yeast extract, peptone, and mixed carbon sources) are discussed in this review. Meanwhile, the environmental friendly and economical carbon sources that are derived from waste materials, such as crude glycerol and wasted sludge, are also discussed and compared.

Phosphorus Chemistry in the Atmosphere of Jupiter: A Reassessment

NASA Astrophysics Data System (ADS)

Borunov, Sergei; Dorofeeva, Vera; Khodakovsky, Igor; Drossart, Pierre; Lellouch, Emmanuel; Encrenaz, Thérèse

1995-02-01

A new distribution of phosphorus compounds in the atmosphere of Jupiter is given, using revised values for the chemical constants. In contrast with previous works, it is shown that phosphine PH 3 remains the most abundant equilibrium gaseous compound even at the upper levels of Jupiter's troposphere. The observed PH 3 abundance is equal to the equilibrium value, at all temperatures above 535 K for solar P and O elemental abundances, and above 600 K for a reasonable range of P and O abundances. P 4O 6 does not take part in the phosphorus cycle on Jupiter.

Using the annual phosphorus loss estimator (APLE) model to evaluate the University of Maryland phosphorus management tool

USDA-ARS?s Scientific Manuscript database

Maryland’s phosphorus site index (PSI) has been used to guide management decisions to minimize the potential for P loss from agricultural fields in Maryland since the adoption of the Water Quality Improvement Act of 1998. The index was recently revised and renamed the University of Maryland Phospho...

Investigations into the chemical structure based selectivity of the microfabricated nitrogen-phosphorus detector

DOE PAGES

Brocato, Terisse A.; Hess, Ryan F.; Moorman, Matthew; ...

2015-10-28

The nitrogen and phosphorus atoms are constituents of some of the most toxic chemical vapors. Nitrogen-phosphorus gas chromatograph detectors (NPDs) rely on selective ionization of such compounds using ionization temperatures typically greater than 600 °C. NPDs have previously been reported to be 7*10 4× and 10 5× more sensitive for nitrogen and phosphorus, respectively, than for carbon. Presented here is an investigation of the structure-based selectivity of a microfabricated nitrogen-phosphorus detector (μNPD). The μNPD presented here is smaller than a dime and can be placed in a system that is 1/100th the size of a commercial NPD. Comparison of responsesmore » of such devices to homologous anilines (p-methoxyaniline, p-fluoroaniline, and aniline) revealed that detection selectivity, determined by the ratio of μNPD to nonselective flame ionization detector (FID) peak areas, is correlated with acid disassociation pK a values for the respective analine. Selectivity was determined to be greatest for p-methoxyaniline, followed by p-fluoroaniline, with aniline having the smallest response. The limit of detection for a nitrogen containing chemical, p-methoxyaniline, using the μNPD was determined to be 0.29 ng compared to 59 ng for a carbon chemical containing no nitrogen or phosphorus, 1,3,5-trimethybenzene. The μNPD presented here has increased detection for nitrogen and phosphorus compared to the FID and with a slight increase in detection of carbon compounds compared to commercial NPD's sensitivity to nitrogen and carbon.« less

Variation laws and release characteristics of phosphorus on surface sediment of Dongting Lake.

PubMed

Zhu, Guangrui; Yang, Ying

2018-05-01

The variation trend and growth rate of P were analyzed by the concentration of the phosphorus fraction on surface sediment of Dongting Lake from 2012 to 2016, to reveal the cumulative effect of P in the actual environment. Meanwhile, the adsorption kinetics and adsorption isotherm were employed to examine the P-release possibility of sediment, which predicts the yearly released sediment phosphorus in Dongting Lake. The actual growth rate of TP (Total Phosphorus) is 53 mg·(kg·year) -1 in East Dongting Lake, 39 mg·(kg·year) -1 in South Dongting Lake, and 29 mg·(kg·year) -1 in West Dongting Lake, while the sum of the phosphorus fraction growth rates has little difference from the rate of TP in sediments of the three areas of Dongting Lake. Furthermore, the Elovich model and the Langmuir crossover-type equations are established to present the adsorption characteristic of sediment in Dongting Lake; the result shows that the sediments play a source role for phosphorus in East and South Dongting Lake from zero equilibrium phosphorus concentration (EPC 0 ) in the present situation, but an adsorption effect on TP is shown in West Dongting Lake. When the conditions of environment change are ignored, the maximum P-sorption level in sediments of East Dongting Lake will reach in 2040 according to the actual growth rate of sediments, while that in West Dongting Lake and South Dongting Lake will be in 2046 and 2061, respectively.

Effects of dietary calcium, phosphorus and magnesium on intranephronic calculosis in rats.

PubMed

Woodward, J C; Jee, W S

1984-12-01

The effects of varying dietary levels of calcium, phosphorus and magnesium on the incidence and severity of intranephronic calculosis were studied. Renal calculi were induced by feeding female rats the AIN-76TM semipurified diet for 4 weeks. During this time period, dietary levels of 350, 450 or 550 mg calcium per 100 g diet did not influence the occurrence of urolithiasis. Increasing dietary magnesium levels from 50 to 350 mg was beneficial in preventing the occurrence of calculi if the diet contained 400 mg or less phosphorus. The protective effects of dietary magnesium were counteracted when dietary phosphorus levels were increased from 400 mg to 550 or 700 mg. If the dietary content of phosphorus and magnesium permitted the formation of renal calculi, the severity of the condition was also influenced by the dietary level of calcium. Some animal groups fed semipurified diets did not have microscopic or radiographic evidence of renal calculi but were found to have significantly elevated renal calcium values. It was suggested that these animals might be in a precalculus-forming state.

Plasmonic Resonance Enhanced Polarization-Sensitive Photodetection by Black Phosphorus in Near Infrared.

PubMed

Venuthurumilli, Prabhu K; Ye, Peide D; Xu, Xianfan

2018-05-22

Black phosphorus, a recently intensely investigated two-dimensional material, is promising for electronic and optoelectronic applications due to its higher mobility and thickness-dependent direct band gap. With its low direct band gap and anisotropic properties in nature, black phosphorus is also suitable for near-infrared polarization-sensitive photodetection. To enhance photoresponsivity of a black phosphorus based photodetector, we demonstrate two designs of plasmonic structures. In the first design, plasmonic bowtie antennas are used to increase the photocurrent, particularly in the armchair direction, where the optical absorption is higher than that in the zigzag direction. The simulated electric field distribution with bowtie structures shows enhanced optical absorption by localized surface plasmons. In the second design, bowtie apertures are used to enhance the inherent polarization selectivity of black phosphorus. A high photocurrent ratio (armchair to zigzag) of 8.7 is obtained. We choose a near-infrared wavelength of 1550 nm to demonstrate the photosensitivity enhancement and polarization selectivity, as it is useful for applications including telecommunication, remote sensing, biological imaging, and infrared polarimetry imaging.

Soil phosphorus heterogeneity promotes tree species diversity and phylogenetic clustering in a tropical seasonal rainforest.

PubMed

Xu, Wumei; Ci, Xiuqin; Song, Caiyun; He, Tianhua; Zhang, Wenfu; Li, Qiaoming; Li, Jie

2016-12-01

The niche theory predicts that environmental heterogeneity and species diversity are positively correlated in tropical forests, whereas the neutral theory suggests that stochastic processes are more important in determining species diversity. This study sought to investigate the effects of soil nutrient (nitrogen and phosphorus) heterogeneity on tree species diversity in the Xishuangbanna tropical seasonal rainforest in southwestern China. Thirty-nine plots of 400 m 2 (20 × 20 m) were randomly located in the Xishuangbanna tropical seasonal rainforest. Within each plot, soil nutrient (nitrogen and phosphorus) availability and heterogeneity, tree species diversity, and community phylogenetic structure were measured. Soil phosphorus heterogeneity and tree species diversity in each plot were positively correlated, while phosphorus availability and tree species diversity were not. The trees in plots with low soil phosphorus heterogeneity were phylogenetically overdispersed, while the phylogenetic structure of trees within the plots became clustered as heterogeneity increased. Neither nitrogen availability nor its heterogeneity was correlated to tree species diversity or the phylogenetic structure of trees within the plots. The interspecific competition in the forest plots with low soil phosphorus heterogeneity could lead to an overdispersed community. However, as heterogeneity increase, more closely related species may be able to coexist together and lead to a clustered community. Our results indicate that soil phosphorus heterogeneity significantly affects tree diversity in the Xishuangbanna tropical seasonal rainforest, suggesting that deterministic processes are dominant in this tropical forest assembly.

Transcriptome analysis of phosphorus stress responsiveness in the seedlings of Dongxiang wild rice (Oryza rufipogon Griff.).

PubMed

Deng, Qian-Wen; Luo, Xiang-Dong; Chen, Ya-Ling; Zhou, Yi; Zhang, Fan-Tao; Hu, Biao-Lin; Xie, Jian-Kun

2018-03-15