WorldWideScience

Sample records for berkelium phosphates

  1. New berkelium isotope: 242Bk

    International Nuclear Information System (INIS)

    A new isotope of berkelium, 242Bk, was produced with a cross section of approx. 10 μb in reactions of boron on uranium and nitrogen on thorium. It decays by electron capture with a half-life of 7 +- 1.3 minutes. The branching ratio for this isotope for alpha decay is less than 1% and that for spontaneous fission is less than 0.03%. 2 figures, 2 tables

  2. Characterization of berkelium(III) dipicolinate and borate compounds in solution and the solid state.

    Science.gov (United States)

    Silver, Mark A; Cary, Samantha K; Johnson, Jason A; Baumbach, Ryan E; Arico, Alexandra A; Luckey, Morgan; Urban, Matthew; Wang, Jamie C; Polinski, Matthew J; Chemey, Alexander; Liu, Guokui; Chen, Kuan-Wen; Van Cleve, Shelley M; Marsh, Matthew L; Eaton, Teresa M; van de Burgt, Lambertus J; Gray, Ashley L; Hobart, David E; Hanson, Kenneth; Maron, Laurent; Gendron, Frédéric; Autschbach, Jochen; Speldrich, Manfred; Kögerler, Paul; Yang, Ping; Braley, Jenifer; Albrecht-Schmitt, Thomas E

    2016-08-26

    Berkelium is positioned at a crucial location in the actinide series between the inherently stable half-filled 5f(7) configuration of curium and the abrupt transition in chemical behavior created by the onset of a metastable divalent state that starts at californium. However, the mere 320-day half-life of berkelium's only available isotope, (249)Bk, has hindered in-depth studies of the element's coordination chemistry. Herein, we report the synthesis and detailed solid-state and solution-phase characterization of a berkelium coordination complex, Bk(III)tris(dipicolinate), as well as a chemically distinct Bk(III) borate material for comparison. We demonstrate that berkelium's complexation is analogous to that of californium. However, from a range of spectroscopic techniques and quantum mechanical calculations, it is clear that spin-orbit coupling contributes significantly to berkelium's multiconfigurational ground state. PMID:27563098

  3. Extraction of tetravalent berkelium and cerium by aliquate-336-S-NO3 quaternary ammonium salt

    International Nuclear Information System (INIS)

    Extraction of tetravalent berkelium and cerium by aliquate-336-S-NO3 quaternary ammonium salt from nitric acid solutions is investigated. The effect of concentrations of nitric acid and extracting agent, nature of an oxidant (potassium bromate, potassium bichromate, mixture of AgNO3 and (NH4)2S2O8) and solvent on the distribution coefficient of berkelium(4) and cerium(4) is studied. It is established that solutions of aliquate-336-S-NO3 in carbon tetrachloride and dichloroethane extract quantitatively tetravalent berkelium from 10-12 M nitric acid solutions and cerium - from 1-10 M nitric acid solutions containing potassium bichromate as an oxidant. It is shown that the value of distribution coefficient for berkelium and cerium depends on the nature of an oxidant and extracting agent concentration. It is established that in the case of extraction by quaternary ammonium salt with one berkelium(4) mole four aliquate-336-SNO3 moles are associated and 1.5-1.6 mole of extracting agent are associated with one cerium(4) mole. It permits to make a conclusion that stoichiometry of extraction reactions by quaternary ammonium salt is not the same for tetravalent berkelium and cerium. It is shown that trivalent transplutonium and rare earth elements are not practically extracted by aliquate-336-S-NO3 from nitric acid solutions

  4. Phosphate sensing

    OpenAIRE

    Bergwitz, Clemens; Jüppner, Harald

    2011-01-01

    Human phosphate homeostasis is regulated at the level of intestinal absorption of phosphate from the diet, release of phosphate through bone resorption, and renal phosphate excretion and involves the actions of parathyroid hormone (PTH), 1,25-dihydroxy-vitamin D (1,25-(OH)2-D), and fibroblast growth factor 23 (FGF23) to maintain circulating phosphate levels within a narrow normal range, which is essential for numerous cellular functions, for the growth of tissues and for bone mineralization. ...

  5. Sodium Phosphate

    Science.gov (United States)

    Sodium phosphate is used in adults 18 years of age or older to empty the colon (large intestine, bowel) ... view of the walls of the colon. Sodium phosphate is in a class of medications called saline ...

  6. Phosphate salts

    Science.gov (United States)

    ... levels that are too high, and for preventing kidney stones. They are also taken for treating osteomalacia (often ... But intravenous phosphate salts should not be used. Kidney stones (nephrolithiasis). Taking potassium phosphate by mouth might help ...

  7. Phosphate salts

    Science.gov (United States)

    ... for children 9-18 years of age. Phosphate salts are POSSIBLY UNSAFE if the amount of phosphate consumed (expressed as phosphorous) exceeds the tolerable upper intake level (UL). The ULs are 3 grams per day for children 1-8 years; and 4 grams per day ...

  8. Intestinal Phosphate Transport

    OpenAIRE

    Sabbagh, Yves; Giral, Hector; Caldas, Yupanqui; Levi, Moshe; Schiavi, Susan C.

    2011-01-01

    Phosphate is absorbed in the small intestine by at least two distinct mechanisms: paracellular phosphate transport which is dependent on passive diffusion and active transport which occurs through the sodium-dependent phosphate co-transporters. Despite evidence emerging for other ions, regulation of the phosphate specific paracellular pathways remains largely unexplored. In contrast, there is a growing body of evidence that active transport through the sodium-dependent phosphate co-transporte...

  9. Uranium from phosphate ores

    International Nuclear Information System (INIS)

    The following topics are described briefly: the way phosphate fertilizers are made; how uranium is recovered in the phosphate industry; and how to detect covert uranium recovery operations in a phsophate plant

  10. Glucose-6-phosphate dehydrogenase

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003671.htm Glucose-6-phosphate dehydrogenase test To use the sharing features on this page, please enable JavaScript. Glucose-6-phosphate dehydrogenase (G6PD) is a type of ...

  11. Chloroquine Phosphate Oral

    Science.gov (United States)

    Chloroquine phosphate is in a class of drugs called antimalarials and amebicides. It is used to prevent and treat ... Chloroquine phosphate comes as a tablet to take by mouth. For prevention of malaria in adults, one dose is ...

  12. Sodium to phosphate ratios

    International Nuclear Information System (INIS)

    Phosphate chemistry is widely used in fossil-fired utility boilers and many of these phosphate programs use the sodium to phosphate ratio as the controlling parameter. This paper steps through the fundamental chemical analyses to determine a systems Na/PO4 ratio. A mathematical equation is introduced to simply calculate the ratio using the pH and phosphate concentration. This equation is also used to build graphs to chart the boiler's phosphate chemistry. By looking at the dynamic nature of the chemistry, boiler health can be determined. (orig.)

  13. Phosphate, inositol and polyphosphates.

    Science.gov (United States)

    Livermore, Thomas M; Azevedo, Cristina; Kolozsvari, Bernadett; Wilson, Miranda S C; Saiardi, Adolfo

    2016-02-15

    Eukaryotic cells have ubiquitously utilized the myo-inositol backbone to generate a diverse array of signalling molecules. This is achieved by arranging phosphate groups around the six-carbon inositol ring. There is virtually no biological process that does not take advantage of the uniquely variable architecture of phosphorylated inositol. In inositol biology, phosphates are able to form three distinct covalent bonds: phosphoester, phosphodiester and phosphoanhydride bonds, with each providing different properties. The phosphoester bond links phosphate groups to the inositol ring, the variable arrangement of which forms the basis of the signalling capacity of the inositol phosphates. Phosphate groups can also form the structural bridge between myo-inositol and diacylglycerol through the phosphodiester bond. The resulting lipid-bound inositol phosphates, or phosphoinositides, further expand the signalling potential of this family of molecules. Finally, inositol is also notable for its ability to host more phosphates than it has carbons. These unusual organic molecules are commonly referred to as the inositol pyrophosphates (PP-IPs), due to the presence of high-energy phosphoanhydride bonds (pyro- or diphospho-). PP-IPs themselves constitute a varied family of molecules with one or more pyrophosphate moiety/ies located around the inositol. Considering the relationship between phosphate and inositol, it is no surprise that members of the inositol phosphate family also regulate cellular phosphate homoeostasis. Notably, the PP-IPs play a fundamental role in controlling the metabolism of the ancient polymeric form of phosphate, inorganic polyphosphate (polyP). Here we explore the intimate links between phosphate, inositol phosphates and polyP, speculating on the evolution of these relationships. PMID:26862212

  14. Phosphate metabolism and vitamin D

    OpenAIRE

    Fukumoto, Seiji

    2014-01-01

    Phosphate plays many essential roles in our body. To accomplish these functions, serum phosphate needs to be maintained in a certain range. Serum phosphate level is regulated by intestinal phosphate absorption, renal phosphate handling and equilibrium of extracellular phosphate with that in bone or intracellular fluid. Several hormones such as parathyroid hormone, 1,25-dihydroxyvitamin D (1,25(OH)2D) and fibroblast growth factor 23 (FGF23) regulate serum phosphate by modulating intestinal pho...

  15. Radioactivity of phosphate mineral products

    OpenAIRE

    Mitrović Branislava; Vitorović Gordana; Stojanović Mirjana; Vitorović Duško

    2011-01-01

    The phosphate industry is one of the biggest polluters of the environment with uranium. Different products are derived after processing phosphoric ore, such as mineral and phosphate fertilizers and phosphate mineral supplements (dicalcium-and monocalcium phosphate) for animal feeding. Phosphate mineral additives used in animal food may contain a high activity of uranium. Research in this study should provide an answer to the extent in which phosphate minera...

  16. PHOSPHATE MANAGEMENT: FY2010 RESULTS OF PHOSPHATE PRECIPITATION TESTS

    Energy Technology Data Exchange (ETDEWEB)

    Hay, M.; King, W.

    2011-04-04

    The Phosphate Management program seeks to develop treatment options for caustic phosphate solutions resulting from the caustic leaching of the bismuth phosphate sludge. The SRNL subtask investigated the precipitation of phosphate salts from caustic solutions through addition of fluoride and by crystallization. The scoping tests examined the: precipitation of phosphate by the addition of sodium fluoride to form the sodium fluorophosphate double salt, Na{sub 7}F(PO{sub 4}){sub 2} {center_dot} 19H{sub 2}O, crystallization of phosphate by reducing the temperature of saturated phosphate solutions, and combinations of precipitation and crystallization. A simplified leachate simulant was used in the study produced by dissolving sodium phosphate in 1 M to 3.5 M sodium hydroxide solutions. The results show that all three processes; precipitation with sodium fluoride, crystallization, and combined precipitation/crystallization can be effective for removing large amounts of phosphate from solution. The combined process of precipitation/crystallization showed >90% removal of phosphate at all hydroxide concentrations when cooling a non-saturated phosphate solution from 65 C to 25 C. Based on the measured solubility of sodium phosphate, pH adjustment/caustic addition will also remove large amounts of phosphate from solution (>80%). For all three processes, the phosphate concentration in the caustic solution must be managed to keep the phosphate from becoming too concentrated and thereby potentially forming a solid mass of sodium phosphate after an effective phosphate removal process.

  17. Metal-phosphate binders

    Science.gov (United States)

    Howe, Beth Ann [Lewistown, IL; Chaps-Cabrera, Jesus Guadalupe [Coahuila, MX

    2009-05-12

    A metal-phosphate binder is provided. The binder may include an aqueous phosphoric acid solution, a metal-cation donor including a metal other than aluminum, an aluminum-cation donor, and a non-carbohydrate electron donor.

  18. Dysregulation of phosphate metabolism and conditions associated with phosphate toxicity

    OpenAIRE

    Brown, Ronald B; Razzaque, Mohammed S

    2015-01-01

    Phosphate homeostasis is coordinated and regulated by complex cross-organ talk through delicate hormonal networks. Parathyroid hormone (PTH), secreted in response to low serum calcium, has an important role in maintaining phosphate homeostasis by influencing renal synthesis of 1,25-dihydroxyvitamin D, thereby increasing intestinal phosphate absorption. Moreover, PTH can increase phosphate efflux from bone and contribute to renal phosphate homeostasis through phosphaturic effects. In addition,...

  19. Uranium from phosphate ores

    International Nuclear Information System (INIS)

    Phosphate rock, the major raw material for phosphate fertilizers, contains uranium that can be recovered when the rock is processed. This makes it possible to produce uranium in a country that has no uranium ore deposits. The author briefly describes the way that phosphate fertilizers are made, how uranium is recovered in the phosphate industry, and how to detect uranium recovery operations in a phosphate plant. Uranium recovery from the wet-process phosphoric acid involves three unit operations: (1) pretreatment to prepare the acid; (2) solvent extraction to concentrate the uranium; (3) post treatment to insure that the acid returning to the acid plant will not be harmful downstream. There are 3 extractants that are capable of extracting uranium from phosphoric acid. The pyro or OPPA process uses a pyrophosphoric acid that is prepared on site by reacting an organic alcohol (usually capryl alcohol) with phosphorous pentoxide. The DEPA-TOPO process uses a mixture of di(2-ethylhexyl)phosphoric acid (DEPA) and trioctyl phosphine oxide (TOPO). The components can be bought separately or as a mixture. The OPAP process uses octylphenyl acid phosphate, a commercially available mixture of mono- and dioctylphenyl phosphoric acids. All three extractants are dissolved in kerosene-type diluents for process use

  20. Phosphate taxis in Pseudomonas aeruginosa.

    OpenAIRE

    Kato, J.; Ito, A.; Nikata, T; Ohtake, H

    1992-01-01

    Pseudomonas aeruginosa was shown to be attracted to phosphate. The chemotactic response was induced by phosphate starvation. The specificity of chemoreceptors for phosphate was high so that no other tested phosphorus compounds elicited a chemotactic response as strong as that elicited by phosphate. Competition experiments showed that the chemoreceptors for phosphate appeared to be different from those for the common amino acids. Mutants constitutive for alkaline phosphatase showed the chemota...

  1. Genetic disorders of phosphate regulation

    OpenAIRE

    Gattineni, Jyothsna; Baum, Michel

    2012-01-01

    Regulation of phosphate homeostasis is critical for many biological processes, and both hypophosphatemia and hyperphosphatemia can have adverse clinical consequences. Only a very small percentage (1%) of total body phosphate is present in the extracellular fluid, which is measured by routine laboratory assays and does not reflect total body phosphate stores. Phosphate is absorbed from the gastrointestinal tract via the transcellular route [sodium phosphate cotransporter 2b (NaPi2b)] and acros...

  2. Uranium production from phosphates

    International Nuclear Information System (INIS)

    According to estimates of the world's uranium consumption, exploitation of most rich sources is expected by the 1980's. Forecasts show that the rate of uranium consumption will increase towards the end of the century. It is therefore desirable to exploit poor sources not yet in use. In the near future, the most reasonable source for developing uranium is phosphate rock. Uranium reserves in phosphates are estimated at a few million tons. Production of uranium from phosphates is as a by-product of phosphate rock processing and phosphoric acid production; it will then be possible to save the costs incurred in crushing and dissolving the rock when calculating uranium production costs. Estimates show that the U.S. wastes about 3,000 tons of uranium per annum in phosphoric acid based fertilisers. Studies have also been carried out in France, Yugoslavia and India. In Israel, during the 1950's, a small plant was operated in Haifa by 'Chemical and Phosphates'. Uranium processes have also been developed by linking with the extraction processes at Arad. Currently there is almost no activity on this subject because there are no large phosphoric acid plants which would enable production to take place on a reasonable scale. Discussions are taking place about the installation of a plant for phosphoric acid production utilising the 'wet process', producing 200 to 250,000 tons P2O5 per annum. It is necessary to combine these facilities with uranium production plant. (author)

  3. Phosphate Mines, Jordan

    Science.gov (United States)

    2008-01-01

    Jordan's leading industry and export commodities are phosphate and potash, ranked in the top three in the world. These are used to make fertilizer. The Jordan Phosphate Mines Company is the sole producer, having started operations in 1935. In addition to mining activities, the company produces phosphoric acid (for fertilizers, detergents, pharmaceuticals), diammonium phosphate (for fertilizer), sulphuric acid (many uses), and aluminum fluoride (a catalyst to make aluminum and magnesium). The image covers an area of 27.5 x 49.4 km, was acquired on September 17, 2005, and is located near 30.8 degrees north latitude, 36.1 degrees east longitude. The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  4. Research on Uncrystallized Phosphating Film

    Institute of Scientific and Technical Information of China (English)

    TANG En-jun; XING Ze-kuan

    2004-01-01

    This article excogitated a kind of uncrystallized phosphating film bears wearing capacity goodly by adding Ca2 + in normal phosphating solution. This technology is very useful to protect steel parts working in oil from abrasion.

  5. Glucose-6-phosphate dehydrogenase deficiency

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000528.htm Glucose-6-phosphate dehydrogenase deficiency To use the sharing features on this page, please enable JavaScript. Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a condition ...

  6. Anilinium dihydrogen phosphate

    Czech Academy of Sciences Publication Activity Database

    Kaman, Ondřej; Smrčok, L.; Gyepes, R.; Havlíček, D.

    2012-01-01

    Roč. 68, č. 2 (2012), "o57"-"o60". ISSN 0108-2701 Institutional research plan: CEZ:AV0Z10100521 Keywords : anilinium * dihydrogen phosphate * crystal structure * hydrogen bonds Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.492, year: 2012 http://scripts.iucr.org/cgi-bin/paper?S0108270111054874

  7. 21 CFR 184.1434 - Magnesium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Magnesium phosphate. 184.1434 Section 184.1434 Food... Specific Substances Affirmed as GRAS § 184.1434 Magnesium phosphate. (a) Magnesium phosphate includes both magnesium phosphate, dibasic, and magnesium phosphate, tribasic. Magnesium phosphate, dibasic...

  8. Calcium Phosphate Biomaterials: An Update

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Current calcium phosphate (CaP) biomaterials for bone repair, substitution, augmentation and regeneration include hydroxyapatite ( HA ) from synthetic or biologic origin, beta-tricalcium phosphate ( β-TCP ) , biphasic calcium phosphate (BCP), and are available as granules, porous blocks, components of composites (CaP/polymer) cements, and as coatings on orthopedic and dental implants. Experimental calcium phosphate biomaterials include CO3- and F-substituted apatites, Mg-and Zn-substituted β-TCP, calcium phosphate glasses. This paper is a brief review of the different types of CaP biomaterials and their properties such as bioactivity, osteoconductivity, osteoinductivity.

  9. Biomediated continuous release phosphate fertilizer

    Science.gov (United States)

    Goldstein, Alan H.; Rogers, Robert D.

    1999-01-01

    A composition is disclosed for providing phosphate fertilizer to the root zone of plants. The composition comprises a microorganism capable of producing and secreting a solubilization agent, a carbon source for providing raw material for the microorganism to convert into the solubilization agent, and rock phosphate ore for providing a source of insoluble phosphate that is solubilized by the solubilization agent and released as soluble phosphate. The composition is provided in a physical form, such as a granule, that retains the microorganism, carbon source, and rock phosphate ore, but permits water and soluble phosphate to diffuse into the soil. A method of using the composition for providing phosphate fertilizer to plants is also disclosed.

  10. Layered metal uranyl phosphates

    International Nuclear Information System (INIS)

    HUO2PO4·4H2O (HUP) forms a laminar intercalate with butylamine, c = 29.30(5) angstrom, which accepts cationic metals in exchange for the n-butylammonium ions. Hydrated uranyl metal phosphates M(UO2PO4)2·nH2O (M=Mn,Co,Ni,Cu,Zn,Cd) are obtained by ionic exchange and were studied by thermal analysis and X-ray diffraction. The tetragonal structures of all these product compounds are derived from HUP. The diffuse electronic reflectance spectra of every sample show characteristic UO22+ absorption bands. In the spectra of the Co, Ni and Cu phosphates there are other bands in the 500-800 nm zone compatible with their observed aquocation transitions

  11. Dysregulation of phosphate metabolism and conditions associated with phosphate toxicity.

    Science.gov (United States)

    Brown, Ronald B; Razzaque, Mohammed S

    2015-01-01

    Phosphate homeostasis is coordinated and regulated by complex cross-organ talk through delicate hormonal networks. Parathyroid hormone (PTH), secreted in response to low serum calcium, has an important role in maintaining phosphate homeostasis by influencing renal synthesis of 1,25-dihydroxyvitamin D, thereby increasing intestinal phosphate absorption. Moreover, PTH can increase phosphate efflux from bone and contribute to renal phosphate homeostasis through phosphaturic effects. In addition, PTH can induce skeletal synthesis of another potent phosphaturic hormone, fibroblast growth factor 23 (FGF23), which is able to inhibit renal tubular phosphate reabsorption, thereby increasing urinary phosphate excretion. FGF23 can also fine-tune vitamin D homeostasis by suppressing renal expression of 1-alpha hydroxylase (1α(OH)ase). This review briefly discusses how FGF23, by forming a bone-kidney axis, regulates phosphate homeostasis, and how its dysregulation can lead to phosphate toxicity that induces widespread tissue injury. We also provide evidence to explain how phosphate toxicity related to dietary phosphorus overload may facilitate incidence of noncommunicable diseases including kidney disease, cardiovascular disease, cancers and skeletal disorders. PMID:26131357

  12. A vacuolar phosphate transporter essential for phosphate homeostasis in Arabidopsis

    OpenAIRE

    Liu, Jinlong; Yang, Lei; Luan, Mingda; Wang, Yuan; Zhang, Chi; Zhang, Bin; Shi, Jisen; Zhao, Fu-Geng; Lan, Wenzhi; Luan, Sheng

    2015-01-01

    Phosphate is an essential nutrient for plant growth, and inorganic phosphate (Pi) is stored largely in the vacuole of plant cells. Thus, vacuolar Pi maintains homeostasis of cytosolic Pi to ensure an optimal Pi supply for plants under variable Pi status in the soil. This study uncovered in Arabidopsis a vacuolar phosphate transporter, VPT1, that mediates vacuolar Pi sequestration. Lack of VPT1 caused growth defects under both low-Pi and high-Pi conditions, implicating VPT1 in plant adaptation...

  13. Pyridoxal phosphate-dependent neonatal epileptic encephalopathy

    OpenAIRE

    Bagci, S.; Zschocke, J.; Hoffmann, G F; Bast, T.; Klepper, J; Müller, A.; Heep, A; Bartmann, P.; Franz, A R

    2009-01-01

    Pyridox(am)ine-5′-phosphate oxidase converts pyridoxine phosphate and pyridoxamine phosphate to pyridoxal phosphate, a cofactor in many metabolic reactions, including neurotransmitter synthesis. A family with a mutation in the pyridox(am)ine-5′-phosphate oxidase gene presenting with neonatal seizures unresponsive to pyridoxine and anticonvulsant treatment but responsive to pyridoxal phosphate is described. Pyridoxal phosphate should be considered in neonatal epileptic encephalopathy unrespons...

  14. Integrated assessment of the phosphate industry

    International Nuclear Information System (INIS)

    The phosphate industry in the United States includes three major activities, namely, mining and milling of phosphate rock, phosphate product manufacture, and phosphate product use. Phosphatic materials contain uranium, thorium, and their decay products in greater than background amounts. This assessment of the radiological impacts associated with the redistribution of radioactive components of phosphate materials may provide insight into the effects of uranium extraction from phosphate materials for use in the nuclear fuel cycle

  15. Phosphate Test 2.0

    OpenAIRE

    Stalder, Etienne; Zumbuehl, Andreas

    2014-01-01

    The accurate measurement of the phosphate content of a liposomal suspension is important when working with differential scanning calorimetry. Standard phosphate tests date back several decades and require extended hands-on time. Here, we present a rapid version of a phosphate test taking advantage of microwave-assisted chemical digestion and multiwell plate reading technology allowing for the fast and accurate testing of many samples in parallel.

  16. Structural classification of phosphate glasses

    International Nuclear Information System (INIS)

    A structural classification of phosphate glasses is proposed. Following types of phosphate glasses are distinguished: discontinuous polymeric structure glasses (phosphate and mixed chains and rings containing glasses), continuous spatial network structure glasses (ultraphosphate and mixed network glasses) and non-polymeric structure glasses (oxide-halide and halide glasses, stuffed with ortho- and pyrophosphate-like groups). Type of the structure determines in a considerable degree the relation between glass composition and properties. (author). 25 refs

  17. Inositol phosphates in the environment.

    OpenAIRE

    Turner, Benjamin L.; Papházy, Michael J; Haygarth, Philip M.; McKelvie, Ian D

    2002-01-01

    The inositol phosphates are a group of organic phosphorus compounds found widely in the natural environment, but that represent the greatest gap in our understanding of the global phosphorus cycle. They exist as inositols in various states of phosphorylation (bound to between one and six phosphate groups) and isomeric forms (e.g. myo, D-chiro, scyllo, neo), although myo-inositol hexakisphosphate is by far the most prevalent form in nature. In terrestrial environments, inositol phosphates are ...

  18. 21 CFR 137.175 - Phosphated flour.

    Science.gov (United States)

    2010-04-01

    ... Related Products § 137.175 Phosphated flour. Phosphated flour, phosphated white flour, and phosphated wheat flour, conform to the definition and standard of identity, and are subject to the requirements for... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Phosphated flour. 137.175 Section 137.175 Food...

  19. Triphenyl phosphate allergy from spectacle frames

    DEFF Research Database (Denmark)

    Carlsen, L; Andersen, K E; Egsgaard, Helge;

    1986-01-01

    A case of triphenyl phosphate allergy from spectacle frames is reported. Patch tests with analytical grade triphenyl phosphate, tri-m-cresyl phosphate, and tri-p-cresyl phosphate in the concentrations 5%, 0.5% and 0.05% pet. showed positive reactions to 0.05% triphenyl phosphate and 0.5% tri-m-cr...

  20. Light weight phosphate cements

    Science.gov (United States)

    Wagh, Arun S.; Natarajan, Ramkumar,; Kahn, David

    2010-03-09

    A sealant having a specific gravity in the range of from about 0.7 to about 1.6 for heavy oil and/or coal bed methane fields is disclosed. The sealant has a binder including an oxide or hydroxide of Al or of Fe and a phosphoric acid solution. The binder may have MgO or an oxide of Fe and/or an acid phosphate. The binder is present from about 20 to about 50% by weight of the sealant with a lightweight additive present in the range of from about 1 to about 10% by weight of said sealant, a filler, and water sufficient to provide chemically bound water present in the range of from about 9 to about 36% by weight of the sealant when set. A porous ceramic is also disclosed.

  1. Copper scandium zirconium phosphate

    DEFF Research Database (Denmark)

    Bond, Andrew David; Warner, Terence Edwin

    2013-01-01

    The title compound, with nominal formula Cu(2)ScZr(PO(4))(3), has a beige coloration and displays fast Cu(+) cation conduction at elevated temperatures. It adopts a NASICON-type structure in the space group R3c. The examined crystal was an obverse-reverse twin with approximately equal twin...... components. The [Sc(III)Zr(IV)(PO(4))(3)](2-) framework is composed of corner-sharing Sc/ZrO(6) octahedra and PO(4) tetrahedra. The Sc and Zr atoms are disordered on one atomic site on a crystallographic threefold axis. The P atom of the phosphate group lies on a crystallographic twofold axis. Nonframework...... Cu(+) cations occupy three positions. Two of the Cu(+) positions generate an approximately circular distribution around a site of 3 symmetry, referred to as the M1 site in the NASICON-type structure. The other Cu(+) position is situated close to the twofold symmetric M2 site, displaced...

  2. Phosphate transport and sensing in Saccharomyces cerevisiae.

    OpenAIRE

    Wykoff, D D; O'Shea, E K

    2001-01-01

    Cellular metabolism depends on the appropriate concentration of intracellular inorganic phosphate; however, little is known about how phosphate concentrations are sensed. The similarity of Pho84p, a high-affinity phosphate transporter in Saccharomyces cerevisiae, to the glucose sensors Snf3p and Rgt2p has led to the hypothesis that Pho84p is an inorganic phosphate sensor. Furthermore, pho84Delta strains have defects in phosphate signaling; they constitutively express PHO5, a phosphate starvat...

  3. Genetic Determinants of Phosphate Response in Drosophila

    OpenAIRE

    Clemens Bergwitz; Wee, Mark J.; Sumi Sinha; Joanne Huang; Charles DeRobertis; Mensah, Lawrence B.; Jonathan Cohen; Adam Friedman; Meghana Kulkarni; Yanhui Hu; Arunachalam Vinayagam; Michael Schnall-Levin; Bonnie Berger; Perkins, Lizabeth A.; Mohr, Stephanie E.

    2012-01-01

    Phosphate is required for many important cellular processes and having too little phosphate or too much can cause disease and reduce life span in humans. However, the mechanisms underlying homeostatic control of extracellular phosphate levels and cellular effects of phosphate are poorly understood. Here, we establish Drosophila melanogaster as a model system for the study of phosphate effects. We found that Drosophila larval development depends on the availability of phosphate in the medium. ...

  4. Genetic Determinants of Phosphate Response in Drosophila

    OpenAIRE

    Bergwitz, Clemens; Wee, Mark J.; Sinha, Sumi; Huang, Joanne Hyunjung; DeRobertis, Charles; Mensah, Lawrence; Cohen, Jonathan Brewer; Friedman, Adam Amiel Laufer; Kulkarni, Meghana; Hu, Yanhui; Vinayagam, Arunachalam; Schnall-Levin, Michael; Berger, Bonnie; Perkins, Lizabeth A; Mohr, Stephanie

    2013-01-01

    Phosphate is required for many important cellular processes and having too little phosphate or too much can cause disease and reduce life span in humans. However, the mechanisms underlying homeostatic control of extracellular phosphate levels and cellular effects of phosphate are poorly understood. Here, we establish Drosophila melanogaster as a model system for the study of phosphate effects. We found that Drosophila larval development depends on the availability of phosphate in the medium. ...

  5. Triphenyl phosphate allergy from spectacle frames

    DEFF Research Database (Denmark)

    Carlsen, Lars; Andersen, Klaus E.; Egsgaard, Helge

    1986-01-01

    A case of triphenyl phosphate allergy from spectacle frames is reported. Patch tests with analytical grade triphenyl phosphate, tri-m-cresyl phosphate, and tri-p-cresyl phosphate in the concentrations 5%, 0.5% and 0.05% pet. showed positive reactions to 0.05% triphenyl phosphate and 0.5% tri......-m-cresyl phosphate, but no reaction to tri-p-cresyl phosphate. Gas chromatography of the tricresyl phosphate 5% pet. patch test material supplied from Trolab showed that it contained a mixture of a wide range of triaryl phosphates, including 0.08% triphenyl phosphate which is above the threshold for detecting...... triphenyl phosphate allergy in our patient....

  6. Uranium leaching from phosphate rock

    International Nuclear Information System (INIS)

    Uranium in phosphate rock was removed by means of alkaline leach solutions. Ammonium carbonate/bicarbonate solution produced a very stable uranyl carbonate compound which was separated by centrifugation. Radiometric analysis showed that about 40% of uranium was solubilized and it can be recuperated. This process could be used before the manufacture of phosphatic fertilizers and the final products would contain smaller uranium quantities. (author). 8 refs., 4 figs

  7. 21 CFR 520.823 - Erythromycin phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Erythromycin phosphate. 520.823 Section 520.823... DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.823 Erythromycin phosphate. (a) Specifications. Erythromycin phosphate is the phosphate salt of the antibiotic substance...

  8. 21 CFR 573.320 - Diammonium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Diammonium phosphate. 573.320 Section 573.320 Food... Additive Listing § 573.320 Diammonium phosphate. The food additive diammonium phosphate may be safely used... crude protein from diammonium phosphate, adequate directions for use and a prominent statement,...

  9. Non-phosphate degradation products of tributyl phosphate

    International Nuclear Information System (INIS)

    Tributyl phosphate(TBP) was compulsively degraded with nitric acid and/or uranium nitrate at elevated temperature around 105 degrees C. Experimental results indicates major non-phosphate degradation products are butyl nitrate (C4H9NO3), propionic acid (C2H5COOH), acetic acid (CH3COOH), butyric acid (C3H7COOH) and butyl alcohol (C4H9OH) in ascending order of quantity. Degrading rate in uranium free system is less than that in uranium coexisting system. Carboxylic acids were not produced in uranium free system, and only acetic acid was identified in case of without supplying nitric acid from aqueous phase. Moreover, from the experimental study on the reactivity of each non-phosphate product with nitric acid, carboxylic acids were identified as byproducts of butyl alcohol and butyl nitrate, and each carboxylic acid was stable in these degrading conditions. Finally, butyl alcohol is considered as one of intermediate products to butyl nitrate and carboxylic acids. From this study, the non-phosphate degradation products of TBP is identified and the degrading reaction pass is proposed. Extraction behavior of each non-phosphate product and reactivity of degraded TBP are also elucidated

  10. Uranium endowments in phosphate rock

    International Nuclear Information System (INIS)

    This study seeks to identify and specify the components that make up the prospects of U recovery from phosphate rock. A systems approach is taken. The assessment includes i) reviewing past recovery experience and lessons learned; ii) identifying factors that determine recovery; and iii) establishing a contemporary evaluation of U endowments in phosphate rock reserves, as well as the available and recoverable amounts from phosphate rock and phosphoric acid production. We find that in the past, recovery did not fulfill its potential and that the breakup of the Soviet Union worsened then-favorable recovery market conditions in the 1990s. We find that an estimated 5.7 million tU may be recoverable from phosphate rock reserves. In 2010, the recoverable tU from phosphate rock and phosphoric acid production may have been 15,000 tU and 11,000 tU, respectively. This could have filled the world U supply-demand gap for nuclear energy production. The results suggest that the U.S., Morocco, Tunisia, and Russia would be particularly well-suited to recover U, taking infrastructural considerations into account. We demonstrate future research needs, as well as sustainability orientations. We conclude that in order to promote investment and production, it seems necessary to establish long-term contracts at guaranteed prices, ensuring profitability for phosphoric acid producers. - Highlights: • We identify components that underlie the recovery of uranium from phosphate rock. • We estimate that 11,000 tU may have been recoverable from phosphoric acid in 2010. • Recovery is a resource conservation and environmental pollution control strategy. • To ensure investment in recovery technology, profitability needs to be secured

  11. Uranium endowments in phosphate rock

    Energy Technology Data Exchange (ETDEWEB)

    Ulrich, Andrea E., E-mail: andrea.ulrich@env.ethz.ch [Institute for Environmental Decisions (IED), Natural and Social Science Interface, ETH Zurich Universitässtrasse 22, 8092 Zurich (Switzerland); Institute for Agricultural Sciences, Plant Nutrition, ETH Zurich, Eschikon 33, 8315 Lindau (Switzerland); Schnug, Ewald, E-mail: e.schnug@tu-braunschweig.de [Department of Life Sciences, Technical University of Braunschweig, Pockelsstraße 14, D-38106 Braunschweig (Germany); Prasser, Horst-Michael, E-mail: prasser@lke.mavt.ethz.ch [Institute of Energy Technology, Laboratory of Nuclear Energy Systems, ETH Zurich, Sonneggstrasse 3, 8092 Zurich (Switzerland); Frossard, Emmanuel, E-mail: emmanuel.frossard@usys.ethz.ch [Institute for Agricultural Sciences, Plant Nutrition, ETH Zurich, Eschikon 33, 8315 Lindau (Switzerland)

    2014-04-01

    This study seeks to identify and specify the components that make up the prospects of U recovery from phosphate rock. A systems approach is taken. The assessment includes i) reviewing past recovery experience and lessons learned; ii) identifying factors that determine recovery; and iii) establishing a contemporary evaluation of U endowments in phosphate rock reserves, as well as the available and recoverable amounts from phosphate rock and phosphoric acid production. We find that in the past, recovery did not fulfill its potential and that the breakup of the Soviet Union worsened then-favorable recovery market conditions in the 1990s. We find that an estimated 5.7 million tU may be recoverable from phosphate rock reserves. In 2010, the recoverable tU from phosphate rock and phosphoric acid production may have been 15,000 tU and 11,000 tU, respectively. This could have filled the world U supply-demand gap for nuclear energy production. The results suggest that the U.S., Morocco, Tunisia, and Russia would be particularly well-suited to recover U, taking infrastructural considerations into account. We demonstrate future research needs, as well as sustainability orientations. We conclude that in order to promote investment and production, it seems necessary to establish long-term contracts at guaranteed prices, ensuring profitability for phosphoric acid producers. - Highlights: • We identify components that underlie the recovery of uranium from phosphate rock. • We estimate that 11,000 tU may have been recoverable from phosphoric acid in 2010. • Recovery is a resource conservation and environmental pollution control strategy. • To ensure investment in recovery technology, profitability needs to be secured.

  12. Phosphorus release from phosphate rock and iron phosphate by low-molecular-weight organic acids

    Institute of Scientific and Technical Information of China (English)

    XU Ren-kou; ZHU Yong-guan; David Chittleborough

    2004-01-01

    Low-molecular-weight(LMW) organic acids widely exist in soils, particularly in the rhizosphere. A series of batch experiments were carried out to investigate the phosphorus release from rock phosphate and iron phosphate by Iow-molecular-weight organic acids.Results showed that citric acid had the highest capacity to solubilize P from both rock and iron phosphate. P solubilization from rock phosphate and iron phosphate resulted in net proton consumption. P release from rock phosphate was positively correlated with the pKa values. P release from iron phosphate was positively correlated with Fe-organic acid stability constants except for aromatic acids, but was not correlated with PKa. Increase in the concentrations of organic acids enhanced P solubilization from both rock and iron phosphate almost linearrly. Addition of phenolic compounds further increased the P release from iron phosphate. Initial solution pH had much more substantial effect on P release from rock phosphate than from iron phosphate.

  13. Photorelease of phosphates: Mild methods for protecting phosphate derivatives

    Directory of Open Access Journals (Sweden)

    Sanjeewa N. Senadheera

    2014-08-01

    Full Text Available We have developed a new photoremovable protecting group for caging phosphates in the near UV. Diethyl 2-(4-hydroxy-1-naphthyl-2-oxoethyl phosphate (14a quantitatively releases diethyl phosphate upon irradiation in aq MeOH or aq MeCN at 350 nm, with quantum efficiencies ranging from 0.021 to 0.067 depending on the solvent composition. The deprotection reactions originate from the triplet excited state, are robust under ambient conditions and can be carried on to 100% conversion. Similar results were found with diethyl 2-(4-methoxy-1-naphthyl-2-oxoethyl phosphate (14b, although it was significantly less efficient compared with 14a. A key step in the deprotection reaction in aq MeOH is considered to be a Favorskii rearrangement of the naphthyl ketone motif of 14a,b to naphthylacetate esters 25 and 26. Disruption of the ketone-naphthyl ring conjugation significantly shifts the photoproduct absorption away from the effective incident wavelength for decaging of 14, driving the reaction to completion. The Favorskii rearrangement does not occur in aqueous acetonitrile although diethyl phosphate is released. Other substitution patterns on the naphthyl or quinolin-5-yl core, such as the 2,6-naphthyl 10 or 8-benzyloxyquinolin-5-yl 24 platforms, also do not rearrange by aryl migration upon photolysis and, therefore, do not proceed to completion. The 2,6-naphthyl ketone platform instead remains intact whereas the quinolin-5-yl ketone fragments to a much more complex, highly absorbing reaction mixture that competes for the incident light.

  14. Glucose-6-Phosphate Dehydrogenase Deficiency Overview

    Science.gov (United States)

    ... Drugs GARD Information Navigator FAQs About Rare Diseases Glucose-6-phosphate dehydrogenase deficiency Title Other Names: G6PD ... G6PD deficiency Categories: Newborn Screening Summary Summary Listen Glucose 6 phosphate dehydrogenase (G6PD) deficiency is a hereditary ...

  15. Glucose-6-Phosphate Dehydrogenase Deficiency Overview

    Science.gov (United States)

    ... Information Center (GARD) Print friendly version Glucose-6-phosphate dehydrogenase deficiency Table of Contents Overview Symptoms Cause ... National Institutes of Health. Overview Listen Glucose 6 phosphate dehydrogenase (G6PD) deficiency is a hereditary condition in ...

  16. Sorption properties of tantalum phosphate

    International Nuclear Information System (INIS)

    The sorption properties of tantalum phosphate prepared from solution containing fluoride ions were studied using radioactivity measurements of trace constituents. It was found that this compound is a typical cation exchanger with the capacity of up to 1.6 mmolxg-1 in neutral solution. (author)

  17. 21 CFR 184.1301 - Ferric phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ferric phosphate. 184.1301 Section 184.1301 Food... Specific Substances Affirmed as GRAS § 184.1301 Ferric phosphate. (a) Ferric phosphate (ferric orthophosphate, iron (III) phosphate, FePO4·xH2O, CAS Reg. No. 10045-86-0) is an odorless, yellowish-white...

  18. Biphasic calcium phosphate in periapical surgery

    OpenAIRE

    Suneelkumar, Chinni; Datta, Krithika; Manali R Srinivasan; Kumar, Sampath T

    2008-01-01

    Calcium phosphate ceramics like hydroxyapatite and β -tricalcium phosphate (β -TCP) possess mineral composition that closely resembles that of the bone. They can be good bone substitutes due to their excellent biocompatibility. Biphasic calcium phosphate is a bone substitute which is a mixture of hydroxyapatite and β -tricalcium phosphate in fixed ratios. Studies have demonstrated the osteoconductive potential of this composition. This paper highlights the clinical use of biphasic calcium pho...

  19. 21 CFR 582.5434 - Magnesium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Magnesium phosphate. 582.5434 Section 582.5434 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5434 Magnesium phosphate. (a) Product. Magnesium phosphate (di- and tribasic)....

  20. 21 CFR 182.6290 - Disodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Disodium phosphate. 182.6290 Section 182.6290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... phosphate. (a) Product. Disodium phosphate. (b) Conditions of use. This substance is generally recognized...

  1. 21 CFR 582.1217 - Calcium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Calcium phosphate. 582.1217 Section 582.1217 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1217 Calcium phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic)....

  2. 21 CFR 182.8778 - Sodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium phosphate. 182.8778 Section 182.8778 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... phosphate. (a) Product. Sodium phosphate (mono-, di-, and tribasic). (b) Conditions of use. This...

  3. 21 CFR 582.5778 - Sodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium phosphate. 582.5778 Section 582.5778 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5778 Sodium phosphate. (a) Product. Sodium phosphate (mono-, di-, and tribasic)....

  4. 21 CFR 182.1217 - Calcium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Calcium phosphate. 182.1217 Section 182.1217 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Substances § 182.1217 Calcium phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic)....

  5. 21 CFR 582.6778 - Sodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium phosphate. 582.6778 Section 582.6778 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Sodium phosphate. (a) Product. Sodium phosphate (mono-, di-, and tribasic). (b) Conditions of use....

  6. 21 CFR 182.6285 - Dipotassium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Dipotassium phosphate. 182.6285 Section 182.6285 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD... Dipotassium phosphate. (a) Product. Dipotassium phosphate. (b) Conditions of use. This substance is...

  7. 21 CFR 582.1141 - Ammonium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ammonium phosphate. 582.1141 Section 582.1141 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1141 Ammonium phosphate. (a) Product. Ammonium phosphate (mono- and dibasic). (b)...

  8. 21 CFR 182.8217 - Calcium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Calcium phosphate. 182.8217 Section 182.8217 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic). (b) Conditions of use. This...

  9. 40 CFR 721.5995 - Polyalkyl phosphate.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Polyalkyl phosphate. 721.5995 Section... Substances § 721.5995 Polyalkyl phosphate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a polyalkyl phosphate (PMN P-95-1772)...

  10. 21 CFR 182.6778 - Sodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium phosphate. 182.6778 Section 182.6778 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... phosphate. (a) Product. Sodium phosphate (mono-, di-, and tribasic). (b) Conditions of use. This...

  11. 21 CFR 582.1778 - Sodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium phosphate. 582.1778 Section 582.1778 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1778 Sodium phosphate. (a) Product. Sodium phosphate (mono-, di-, and tribasic)....

  12. 21 CFR 182.1778 - Sodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium phosphate. 182.1778 Section 182.1778 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Substances § 182.1778 Sodium phosphate. (a) Product. Sodium phosphate (mono-, di-, and tribasic)....

  13. 21 CFR 582.6285 - Dipotassium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Dipotassium phosphate. 582.6285 Section 582.6285 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Dipotassium phosphate. (a) Product. Dipotassium phosphate. (b) Conditions of use. This substance is...

  14. 21 CFR 582.6290 - Disodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Disodium phosphate. 582.6290 Section 582.6290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Disodium phosphate. (a) Product. Disodium phosphate. (b) Conditions of use. This substance is...

  15. 21 CFR 582.5301 - Ferric phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ferric phosphate. 582.5301 Section 582.5301 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5301 Ferric phosphate. (a) Product. Ferric phosphate. (b) Conditions of use....

  16. 21 CFR 582.5217 - Calcium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Calcium phosphate. 582.5217 Section 582.5217 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5217 Calcium phosphate. (a) Product. Calcium phosphate (mono-, di-, and tribasic)....

  17. Phosphate analogues in the dissection of mechanism.

    OpenAIRE

    Heidi J. Korhonen; Conway, Louis P.; Hodgson, David R. W.

    2014-01-01

    Phosphoryl group transfer is central to genetic replication, cellular signalling and many metabolic processes. Understanding the mechanisms of phosphorylation and phosphate ester and anhydride cleavage is key to efforts towards biotechnological and biomedical exploitation of phosphate-handling enzymes. Analogues of phosphate esters and anhydrides are indispensable tools, alongside protein mutagenesis and computational methods, for the dissection of phosphoryl transfer mechanisms. Hydrolysable...

  18. Evidence for a signaling axis by which intestinal phosphate rapidly modulates renal phosphate reabsorption

    OpenAIRE

    Berndt, Theresa; Thomas, Leslie F.; Craig, Theodore A.; Sommer, Stacy; Li, Xujian; Bergstralh, Eric J.; Kumar, Rajiv

    2007-01-01

    The mechanisms by which phosphorus homeostasis is preserved in mammals are not completely understood. We demonstrate the presence of a mechanism by which the intestine detects the presence of increased dietary phosphate and rapidly increases renal phosphate excretion. The mechanism is of physiological relevance because it maintains plasma phosphate concentrations in the normal range after ingestion of a phosphate-containing meal. When inorganic phosphate is infused into the duodenum, there is...

  19. Nanoporous sorbent material as an oral phosphate binder and for aqueous phosphate, chromate, and arsenate removal

    OpenAIRE

    Sangvanich, Thanapon; Ngamcherdtrakul, Worapol; Lee, Richard; Morry, Jingga; Castro, David; Fryxell, Glen E.; Yantasee, Wassana

    2014-01-01

    Phosphate removal is both biologically and environmentally important. Biologically, hyperphosphatemia is a critical condition in end-stage chronic kidney disease patients. Patients with hyperphosphatemia are treated long-term with oral phosphate binders to prevent phosphate absorption to the body by capturing phosphate in the gastrointestinal (GI) tract followed by fecal excretion. Environmentally, phosphate levels in natural water resources must be regulated according to limits set forth by ...

  20. Phosphate uptake kinetics by Acinetobacter isolates.

    Science.gov (United States)

    Pauli, A S; Kaitala, S

    1997-02-01

    Acinetobacter isolates from activated sludge treatment plants of forest industry were used as model organisms for polyphosphate accumulating bacteria to study excess phosphate uptake by the overplus phenomenon as well as luxury uptake of phosphate during growth. The initial, rapid phosphate uptake by the phosphorus-starved Acinetobacter isolates (the overplus phenomenon) followed the Michaelis-Menten model (maximum initial phosphate uptake rate 29 mg P g(-1) dry mass (DM) h(-1), half-saturation constant for excess phosphate uptake 17 mg P L(-1)). During the rapid uptake no growth was observed, but most cells contained polyphosphate granules. Also growth and luxury uptake of phosphate could be modeled with the Michaelis-Menten equation (maximum phosphate uptake rate 3.7-12 mg P g(-1) DM h(-1), half-saturation constant for growth 0.47-6.0 mg P L(-1), maximum specific growth rate 0.15-0.55 h(-1)). PMID:18633985

  1. Calcium phosphate in catheter encrustation.

    Science.gov (United States)

    Cox, A J; Harries, J E; Hukins, D W; Kennedy, A P; Sutton, T M

    1987-02-01

    Encrusted catheters from nine female patients were the source of samples of deposits which were examined by X-ray diffraction, atomic absorption spectroscopy, infra-red spectroscopy and extended X-ray absorption fine structure (EXAFS) spectroscopy. In eight samples the only crystalline phase which could be clearly distinguished by X-ray diffraction was ammonium magnesium orthophosphate hexahydrate, NH4MgPO4 X 6H2O, which occurs naturally as the mineral struvite. However, atomic absorption spectroscopy revealed an appreciable concentration of calcium in all samples. Calcium phosphates have previously been detected in catheter deposits. Infra-red and EXAFS spectra were consistent with the calcium phosphate being present as a poorly crystalline hydroxyapatite. Thus the deposits appear to consist of a mixture of crystalline struvite and a form of hydroxyapatite which is not fully crystalline. PMID:3030487

  2. Phosphate fertilizers’ domestic price movement in Vietnam

    Directory of Open Access Journals (Sweden)

    Tuan Trong Luu

    2010-04-01

    Full Text Available This research analyses long-run and short-run co-movements among the three variables “international prices,” “domestic prices,” and “import prices” of phosphate fertilizers using co-integration test, Granger causality test, and VEC model. The findings revealed that the domestic phosphate fertilizer market in Vietnam has well integrated into the international phosphate market since shifts in the domestic phosphate fertilizer price have been in long-run equilibrium with those in the international phosphate fertilizer price. Furthermore, changes in the domestic phosphate fertilizer price were brisker than those in the import price and were uncorrelated with the import prices.

  3. Insight into biological phosphate recovery from sewage.

    Science.gov (United States)

    Ye, Yuanyao; Ngo, Huu Hao; Guo, Wenshan; Liu, Yiwen; Zhang, Xinbo; Guo, Jianbo; Ni, Bing-Jie; Chang, Soon Woong; Nguyen, Dinh Duc

    2016-10-01

    The world's increasing population means that more food production is required. A more sustainable supply of fertilizers mainly consisting of phosphate is needed. Due to the rising consumption of scarce resources and limited natural supply of phosphate, the recovery of phosphate and their re-use has potentially high market value. Sewage has high potential to recover a large amount of phosphate in a circular economy approach. This paper focuses on utilization of biological process integrated with various subsequent processes to concentrate and recycle phosphate which are derived from liquid and sludge phases. The phosphate accumulation and recovery are discussed in terms of mechanism and governing parameters, recovery efficiency, application at plant-scale and economy. PMID:27434305

  4. Application of Calcium Phosphate Materials in Dentistry

    Directory of Open Access Journals (Sweden)

    Jabr S. Al-Sanabani

    2013-01-01

    Full Text Available Calcium phosphate materials are similar to bone in composition and in having bioactive and osteoconductive properties. Calcium phosphate materials in different forms, as cements, composites, and coatings, are used in many medical and dental applications. This paper reviews the applications of these materials in dentistry. It presents a brief history, dental applications, and methods for improving their mechanical properties. Notable research is highlighted regarding (1 application of calcium phosphate into various fields in dentistry; (2 improving mechanical properties of calcium phosphate; (3 biomimetic process and functionally graded materials. This paper deals with most common types of the calcium phosphate materials such as hydroxyapatite and tricalcium phosphate which are currently used in dental and medical fields.

  5. Glucose 6 phosphate dehydrogenase deficiency Review

    OpenAIRE

    Şaşmaz, İlgen

    2009-01-01

    Glucose 6 phosphate dehydrogenase G6PD is the first enzyme of the pentose phosphate pathway providing reducing power to all cells in the form of reduced form of nicotinamide adenine dinucleotide phosphate G6PD deficiency is the most common human enzyme defect being present in more than 400 million people worldwide G6PD deficiency is an X linked hereditary genetic defect caused by mutations in the G6PD gene Clinical presentations include acute hemolytic anemia chronic hemolytic anemia neonatal...

  6. Alpha Klotho and phosphate homeostasis

    OpenAIRE

    Bian, Ao; Xing, Changying; Hu, Ming Chang

    2014-01-01

    The Klotho family consists of three single-pass transmembrane proteins—αKlotho, βKlotho and γKlotho. Each of them combines with fibroblast growth factor (FGF) receptors (FGFRs) to form receptor complexes for various FGF’s. αKlotho is a co-receptor for physiological FGF23 signaling and appears essential for FGF23-mediated regulation of mineral metabolism. αKlotho protein also plays a FGF23-independent role in phosphate homeostasis. Animal experimental studies and clinical observations have dem...

  7. Heterophase synthesis of phosphates of tetravalent metals

    International Nuclear Information System (INIS)

    The conditions have been found for producing dense amorphous phosphates of zirconium, titanium, cerium, and crystalline acid orthophosphates of zirconium from different acidocompounds of these elements and orthophosphoric acid. Thermal stability of synthesized phosphates has been studied within a temperature range 20-1200 deg C. An effect has been established of the initial compound on their dispersity, structure and ion-exchange properties. Infrared absorption spectra of phosphates have been studied in a range 400-4000 cm-1. It has been shown that the method of heterophase reactions makes it possible to reduce considerably the duration of synthesis of the phosphates and consumption of the reagents

  8. Iron-based phosphate binders: do they offer advantages over currently available phosphate binders?

    OpenAIRE

    Negri, Armando Luis; Ureña Torres, Pablo Antonio

    2014-01-01

    Increased cardiovascular morbidity and mortality has been associated with the hyperphosphatemia seen in patients with end-stage chronic kidney disease (CKD). Oral phosphate binders are prescribed in these patients to prevent intestinal absorption of dietary phosphate and reduce serum phosphate. In prospective observational cohorts they have shown to decrease all-cause and cardiovascular mortality risk. Different problems have been associated with currently available phosphate binders as posit...

  9. Phosphate transporters and their function.

    Science.gov (United States)

    Biber, Jürg; Hernando, Nati; Forster, Ian

    2013-01-01

    Plasma phosphate concentration is maintained within a relatively narrow range by control of renal reabsorption of filtered inorganic phosphate (P(i)). P(i) reabsorption is a transcellular process that occurs along the proximal tubule. P(i) flux at the apical (luminal) brush border membrane represents the rate-limiting step and is mediated by three Na(+)-dependent P(i) cotransporters (members of the SLC34 and SLC20 families). The putative proteins responsible for basolateral P(i) flux have not been identified. The transport mechanism of the two kidney-specific SLC34 proteins (NaPi-IIa and NaPi-IIc) and of the ubiquitously expressed SLC20 protein (PiT-2) has been studied by heterologous expression to reveal important differences in kinetics, stoichiometry, and substrate specificity. Studies on the regulation of the abundance of the respective proteins highlight significant differences in the temporal responses to various hormonal and nonhormonal factors that can influence P(i) homeostasis. The phenotypes of mice deficient in NaPi-IIa and NaPi-IIc indicate that NaPi-IIa is responsible for most P(i) renal reabsorption. In contrast, in the human kidney, NaPi-IIc appears to have a relatively greater role. The physiological relevance of PiT-2 to P(i) reabsorption remains to be elucidated. PMID:23398154

  10. Stable Development of Phosphate Fertilizer Sector

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ The rapid growth of China's economy in recent years gave rise to a sound external environment for the development of the phosphate fertilizer industry. With quite a few state agricultural incentives, the initiative of farmers in grain production is much higher, and consumption of phosphate fertilizers has increased constantly.

  11. Thermal stability of phosphate coatings on steel

    Directory of Open Access Journals (Sweden)

    P. Pokorny

    2015-07-01

    Full Text Available The work was validated thermal stability of zinc, manganese and tri-cations phosphate coatings on steel, made from commercial phosphating bath type Pragofos. Thermogravimetric data dehydration of scholzite, phosphophylite and hureaulite coatings in the temperature range 160 °C – 400 °C define the conditions for applying paints with higher firing temperature or thermal spraying ceramic coatings.

  12. Electrochemical phosphate recovery from nanofiltration concentrates

    NARCIS (Netherlands)

    Kappel, C.; Yasadi, K.; Temmink, B.G.; Metz, S.J.; Kemperman, A.J.B.; Nijmeijer, K.; Zwijnenburg, A.; Witkamp, G.J.; Rijnaarts, H.

    2013-01-01

    The high total phosphorus content of raw domestic wastewater with its significant eutrophication potential offers an excellent possibility for phosphate recovery. Continuous recirculation of NF concentrate to an MBR and simultaneous phosphate recovery from the NF concentrate can be applied to produc

  13. Adsorption of Phosphate on Variable Charge Soils

    Institute of Scientific and Technical Information of China (English)

    HUGUO-SONG; ZHUZU-XIANG; 等

    1992-01-01

    The study about the adsorption of phosphate on four variable charge soils and some minerals revealed that two stage adsorption appeared in the adsorption isothems of phosphate on 4 soils and there was a maximum adsorption on Al-oxide-typed surfaces between pH 3.5 to pH 5.5 as suspension pH changed from 2 to 9,but the adsorption amount of phosphate decreased continually as pH rose on Fe-oxide typed surfaces.The adsorption amount of phosphate and the maximum phosphate adsorption pH decreased in the order of yellow-red soil> lateritic red soil> red soil> paddy soil,which was coincided with the content order of amorphous Al oxide.The removement of organic matter and Fe oxide made the maximum phosphate adsorption pH rise from 4.0 to 5.0 and 4.5,respectively.The desorption curves with pH of four soils showed that phosphate desorbed least at pH 5.Generally the desorption was contrary to the adsorption with pH changing.There was a good accordance between adsorption or desorption and the concentration of Al in the suspension.The possible mechanisms of phosphate adsorption are discussed.

  14. Radiological impact of use of phosphatic fertilizers

    International Nuclear Information System (INIS)

    Samples of rock phosphate from various sources used for producing phosphate fertilizers of different types of N, P, NPK and by product gypsum were procured from twenty one fertilizer plants. Radio active counts were recorded. Strategies have been suggested to use fertilizers in a more eco-friendly way. (author). 10 refs., 3 tabs

  15. Thermal stability of phosphated coatings on steels

    Czech Academy of Sciences Publication Activity Database

    Brožek, Vlastimil; Pokorný, P.; Szelag, P.; Cinert, Jakub

    Zagreb: Croatian Metallurgical Society (CMS), 2014 - (Mamuzić, I.). s. 405 ISBN N. [International Symposium of Croatian Metallurgical Society SHMD 2014/11./. 22.06.2014-26.06.2014, Šibenik] Institutional support: RVO:61389021 Keywords : steel phosphating * phosphate coatings * plasma spraying * ceramic coatings * corrosion resistance * bond strength of coatings Subject RIV: CA - Inorganic Chemistry

  16. Genetics Home Reference: pyridoxal 5'-phosphate-dependent epilepsy

    Science.gov (United States)

    ... 5'-phosphate-dependent epilepsy pyridoxal 5'-phosphate-dependent epilepsy Enable Javascript to view the expand/collapse boxes. ... All Close All Description Pyridoxal 5'-phosphate-dependent epilepsy is a condition that involves seizures beginning soon ...

  17. Phosphate Biomineralization of Cambrian Microorganisms

    Science.gov (United States)

    McKay, David S.; Rozanov, Alexei Yu.; Hoover, Richard B.; Westall, Frances

    1998-01-01

    As part of a long term study of biological markers (biomarkers), we are documenting a variety of features which reflect the previous presence of living organisms. As we study meteorites and samples returned from Mars, our main clue to recognizing possible microbial material may be the presence of biomarkers rather than the organisms themselves. One class of biomarkers consists of biominerals which have either been precipitated directly by microorganisms, or whose precipitation has been influenced by the organisms. Such microbe-mediated mineral formation may include important clues to the size, shape, and environment of the microorganisms. The process of fossilization or mineralization can cause major changes in morphologies and textures of the original organisms. The study of fossilized terrestrial organisms can help provide insight into the interpretation of mineral biomarkers. This paper describes the results of investigations of microfossils in Cambrian phosphate-rich rocks (phosphorites) that were found in Khubsugul, Northern Mongolia.

  18. Dominant oceanic bacteria secure phosphate using a large extracellular buffer

    OpenAIRE

    M. V. Zubkov; Martin, A. P.; Hartmann, M.; C. Grob; Scanlan, D. J.

    2015-01-01

    The ubiquitous SAR11 and Prochlorococcus bacteria manage to maintain a sufficient supply of phosphate in phosphate-poor surface waters of the North Atlantic subtropical gyre. Furthermore, it seems that their phosphate uptake may counter-intuitively be lower in more productive tropical waters, as if their cellular demand for phosphate decreases there. By flow sorting 33P-phosphate-pulsed 32P-phosphate-chased cells, we demonstrate that both Prochlorococcus and SAR11 cells exploit an extracellul...

  19. Phosphate transport and arsenate resistance in the cyanobacterium Anabaena variabilis.

    OpenAIRE

    Thiel, T.

    1988-01-01

    Cells of the cyanobacterium Anabaena variabilis starved for phosphate for 3 days took up phosphate at about 100 times the rate of unstarved cells. Kinetic data suggested that a new transport system had been induced by starvation for phosphate. The inducible phosphate transport system was quickly repressed by addition of Pi. Phosphate-starved cells were more sensitive to the toxic effects of arsenate than were unstarved cells, but phosphate could alleviate some of the toxicity. Arsenate was a ...

  20. Sonochemical precipitation of amorphous uranium phosphates from trialkyl phosphate solutions and their thermal conversion to UP2O7

    Czech Academy of Sciences Publication Activity Database

    Doroshenko, I.; Žurková, J.; Moravec, Z.; Bezdička, Petr; Pinkas, J.

    2015-01-01

    Roč. 26, SEP (2015), s. 157-162. ISSN 1350-4177 Institutional support: RVO:61388980 Keywords : Uranium * Phosphates * Sonochemistry * Nuclear waste * Trimethyl phosphate * Triethyl phosphate Subject RIV: CA - Inorganic Chemistry Impact factor: 4.321, year: 2014

  1. Solid state NMR study calcium phosphate ceramics

    International Nuclear Information System (INIS)

    High-resolution 31P and 1H NMR spectra at 40 and 121 MHz 31P and 300 MHz 1H of synthetic and biological samples of calcium phosphates have been obtained by magic angle spinning (MAS) at spinning speeds up to 6.5 kHz, and high power proton decoupling. The samples include crystalline hydroxyapatite, a deficient hydroxyapatite characterized by a Ca/P atomic ratio of 1.5, a poorly crystallized hydroxyapatite, monetite, brushite, octacalcium phosphate, β-tricalcium phosphate and rabbit femoral bone. The interactions between nuclei in unlike structures and the mobility of acid protons are discussed. (author). 11 refs.; 2 figs.; 1 tab

  2. [Adsorption of Phosphate by Lanthanum Hydroxide/Natural Zeolite Composites from Low Concentration Phosphate Solution].

    Science.gov (United States)

    Lin, Jian-wei; Wang, Hong; Zhan, Yan-hui; Chen, Dong-mei

    2016-01-15

    A series of composites of lanthanum hydroxide/natural zeolite ( La( OH) 3/NZ composites) were prepared by co-precipitation method, and these composites were used as adsorbents to remove phosphate from aqueous solution. The phosphate adsorption capacities of different composites prepared with different precipitated pH values were compared in batch mode. The adsorption characteristics of phosphate from aqueous solution on the La(OH)3/NZ composite prepared with the precipitated pH value of 11 was investigated using batch experiments. The results showed that the La(OH)3/NZ composite prepared with the precipitated pH values of 5-7 and 13 had a low adsorption capacity for phosphate in aqueous solution, while the La( OH) 3/NZ composites prepared with the precipitated pH values of 9-12 exhibited much higher phosphate adsorption capacity. The phosphate adsorption capacity of the La (OH)3/NZ composite increased with the increase of the precipitated pH value from 9 to 11, but remained basically unchanged with the increase of the precipitated pH value from 11 to 12. The equilibrium adsorption data of phosphate from aqueous solution on the La ( OH ) 3/NZ composite prepared with the precipitated pH value of 11 could be described by the Langmuir isotherm model with the predicted maximum phosphate adsorption of 44 mg x g(-1) (phosphate solution pH 7 and 30 degrees C). The kinetic data of phosphate adsorption from low concentration phosphate solution on the La(OH)3/NZ composite prepared with the precipitated pH value of 11 well followed a pseudo-second-order model. The presence of Cl- and SO4(2-) in low concentration phosphate solution had no negative effect on phosphate adsorption onto the La(OH)3/NZ composite prepared with the precipitated pH value of 11, while the presence of HCO3- slightly inhibited the adsorption of phosphate. Coexisting humic acid had a negative effect on the adsorption of phosphate at low concentration on the La(OH)3/NZ composite prepared with the

  3. Biological Removal of Phosphate Using Phosphate Solubilizing Bacterial Consortium from Synthetic Wastewater: A Laboratory Scale

    OpenAIRE

    Dipak Paul; Sankar Narayan Sinha

    2015-01-01

    Biological phosphate removal is an important process having gained worldwide attention and widely used for removing phosphorus from wastewater. The present investigation was aimed to screen the efficient phosphate solubilizing bacterial isolates and used to remove phosphate from synthetic wastewater under shaking flasks conditions. Pseudomonas sp. JPSB12, Enterobacter sp. TPSB20, Flavobacterium sp. TPSB23 and mixed bacterial consortium (Pseudomonas sp. JPSB12+Enterobacter sp. TPSB20+Flavobact...

  4. Performance of pineapple slips inoculated with diazotrophic phosphate-solubilizing bacteria and rock phosphate

    OpenAIRE

    Lílian Estrela Borges Baldotto; Marihus Altoé Baldotto; Fábio Lopes Olivares; Adriane Nunes de Souza

    2014-01-01

    Besides fixing N2, some diazotrophic bacteria or diazotrophs, also synthesize organic acids and are able to solubilize rock phosphates, increasing the availability of P for plants. The application of these bacteria to pineapple leaf axils in combination with rock phosphate could increase N and P availability for the crop, due to the bacterial activity of biological nitrogen fixation and phosphate solubilization. The objectives of this study were: (i) to select and characterize diazotrophs abl...

  5. Hydrolysis of pyridoxal-5'-phosphate in plasma in conditions with raised alkaline phosphate.

    OpenAIRE

    Anderson, B B; O'Brien, H.; Griffin, G E; Mollin, D. L.

    1980-01-01

    Hydrolysis of pyridoxal phosphate in plasma was demonstrated in patients with liver disease and other conditions with raised alkaline phosphatase, and this usually closely paralleled the alkaline phosphatase level, whether of liver or bone origin. The endogenous plasma pyridoxal phosphate was inversely related to the alkaline phosphatase, and plasma hydrolysis of pyridoxal phosphate may at least in part be responsible. Very large doses of vitamin B6 may be necessary to compensate for this hyd...

  6. Airborne radioactivity surveys for phosphate in Florida

    Science.gov (United States)

    Moxham, Robert M.

    1954-01-01

    Airborne radioactivity surveys totaling 5, 600 traverse miles were made in 10 areas in Florida, which were thought to be geologically favorable for deposits of uraniferous phosphate. Abnormal radioactivity was recorded in 8 of the 10 areas surveyed. The anomalies are located in Bradford, Clay, Columbia, DeSoto, Dixie, Lake, Marion, Orange, Sumter, Taylor, and Union Counties. Two of the anomalies were investigated briefly on the ground. One resulted from a deposit of river-pebble phosphate in the Peace River valley; the river-pebble samples contain an average of 0.013 percent equivalent uranium. The other anomaly resulted from outcrops of leached phosphatic rock containing as much as 0. 016 percent equivalent uranium. Several anomalies in other areas were recorded at or near localities where phosphate deposits have been reported.

  7. Phosphate coating on stainless steel 304 sensitized

    International Nuclear Information System (INIS)

    The stainless steel 304 can be sensitized when welding processes are applied, that causes the precipitation of chromium carbide in the grain limits, being promoted in this way the formation of galvanic cells and consequently the corrosion process. Using a phosphate coating is possible to retard the physiochemical damages that can to happen in the corrosion process. The stainless steel 304 substrate sensitized it is phosphate to base of Zn-Mn, in a immersion cell very hot. During the process was considered optimization values, for the characterization equipment of X-rays diffraction and scanning electron microscopy was used. The XRD technique confirmed the presence of the phases of manganese phosphate, zinc phosphate, as well as the phase of the stainless steel 304. When increasing the temperature from 60 to 90 C in the immersion process a homogeneous coating is obtained. (Author)

  8. Uranium recovery from phosphate rocks concentrated

    International Nuclear Information System (INIS)

    The reserves, geological data, chemical data and technical flowsheet from COPEBRAS and Goiasfertil ores are described, including the process of mining ore concentration. Samples of Goiasfertil ores are analysed by gravimetric analysis, for phosphate, and spectrofluorimetry for uranium. (author)

  9. Thermal stability of phosphate coatings on steel

    Czech Academy of Sciences Publication Activity Database

    Pokorný, P.; Szelag, P.; Novák, M.; Mastný, L.; Brožek, Vlastimil

    2015-01-01

    Roč. 54, č. 3 (2015), s. 489-492. ISSN 0543-5846 Institutional support: RVO:61389021 Keywords : Steel * phosphates * coatings * structure Subject RIV: CA - Inorganic Chemistry Impact factor: 0.959, year: 2014

  10. Enzyme activity in dialkyl phosphate ionic liquids

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, M.F.; Dunn, J.; Li, L.-L.; Handley-Pendleton, J. M.; van der lelie, D.; Wishart, J. F.

    2011-12-01

    The activity of four metagenomic enzymes and an enzyme cloned from the straw mushroom, Volvariellavolvacea were studied in the following ionic liquids, 1,3-dimethylimidazolium dimethyl phosphate, [mmim][dmp], 1-ethyl-3-methylimidazolium dimethyl phosphate, [emim][dmp], 1-ethyl-3-methylimidazolium diethyl phosphate, [emim][dep] and 1-ethyl-3-methylimidazolium acetate, [emim][OAc]. Activity was determined by analyzing the hydrolysis of para-nitrobenzene carbohydrate derivatives. In general, the enzymes were most active in the dimethyl phosphate ionic liquids, followed by acetate. Generally speaking, activity decreased sharply for concentrations of [emim][dep] above 10% v/v, while the other ionic liquids showed less impact on activity up to 20% v/v.

  11. Mannose 6-, fructose 1-, and fructose 6-phosphates inhibit human natural cell-mediated cytotoxicity.

    OpenAIRE

    Forbes, J T; Bretthauer, R. K.; Oeltmann, T N

    1981-01-01

    In vitro human natural cell-mediated cytotoxicity (NCMC) to K-562, Molt-4, and F-265 cells is inhibited in a dose-dependent manner by mannose 6-phosphate, fructose 1-phosphate and fructose 6-phosphate. This inhibition is not observed with mannose, glucose, fucose, glucose 6-phosphate, mannose 1-phosphate, galactose 1-phosphate, or galactose 6-phosphate. Preincubation of the effector cells, obtained from fresh whole blood, with mannose-6-phosphate, fructose-1-phosphate, or fructose-6-phosphate...

  12. Using phosphate supplementation to reverse hypophosphatemia and phosphate depletion in neurological disease and disturbance.

    Science.gov (United States)

    Håglin, Lena

    2016-06-01

    Hypophosphatemia (HP) with or without intracellular depletion of inorganic phosphate (Pi) and adenosine triphosphate has been associated with central and peripheral nervous system complications and can be observed in various diseases and conditions related to respiratory alkalosis, alcoholism (alcohol withdrawal), diabetic ketoacidosis, malnutrition, obesity, and parenteral and enteral nutrition. In addition, HP may explain serious muscular, neurological, and haematological disorders and may cause peripheral neuropathy with paresthesias and metabolic encephalopathy, resulting in confusion and seizures. The neuropathy may be improved quickly after proper phosphate replacement. Phosphate depletion has been corrected using potassium-phosphate infusion, a treatment that can restore consciousness. In severe ataxia and tetra paresis, complete recovery can occur after adequate replacement of phosphate. Patients with multiple risk factors, often with a chronic disease and severe HP that contribute to phosphate depletion, are at risk for neurologic alterations. To predict both risk and optimal phosphate replenishment requires assessing the nutritional status and risk for re-feeding hypophosphatemia. The strategy for correcting HP depends on the severity of the underlying disease and the goal for re-establishing a phosphate balance to limit the consequences of phosphate depletion. PMID:25909152

  13. Phosphate solubilizing bacteria around Indian peninsula

    Digital Repository Service at National Institute of Oceanography (India)

    DeSouza, M.J.B.D.; Nair, S.; Chandramohan, D.

    organic and combined inorganic compounds accumulated outside the cells as soluble reactive phosphorus (SRP), indicating an efficient regeneration of orthophosphate from various phosphorus compounds . The major forms of phosphorus are solubilized... to be the phosphate solubilizers. These solubilizers of inorganic phosphate were further screened for phosphatase production (mineralisa- tion)12 also. About 1 ml of culture suspension (1 cm cell O.D600 a = 0.1) was inoculated into 10 ml of 0.2 ?m filtered...

  14. Synthesis of Tetracalcium Phosphate at Reduced Temperatures

    OpenAIRE

    Gross, K; Rozīte, E

    2015-01-01

    Tetracalcium phosphate (TTCP) requires the highest synthesis temperatures of all the calcium phosphates, but now a new process is available at 400 oC lower than previously, at 900 oC. Instead of ball-milling reactants for a homogeneous mix, the reactants for solid-state synthesis were assembled in an amorphous phase. Heating produced hydroxyapatite, then oxyapatite and finally TTCP. Amorphous nanoparticles were synthesized and then heated in air or in vacuo. The sequence of solid-state rea...

  15. Novel phosphate glasses for bone regeneration applications

    OpenAIRE

    Burling, Luke Donald

    2006-01-01

    Phosphate glass with additions of sodium, magnesium and/or calcium were investigated for their potential to be used as the reinforcing phase in a completely degradable long fibre composite. Glasses were prepared from phosphate salts as opposed to oxides and melted under air in platinum/gold crucibles. The effect of cation addition on the material properties and biocompatibility was investigated. Glasses were characterised using a number of complimentary techniques, including: XRD, XPS, DSC...

  16. Kinetics of strontium sorption in calcium phosphate

    International Nuclear Information System (INIS)

    Kinetics of strontium sorption by highly dispersed solids: tricalcium phosphate (Ca3(PO4)2, TCP) and hydroxyapatite (Ca5(PO4)3)H, HAP) were investigated. Analysis of sorption data was made taking into consideration composition and morphology of ultra micro particles. Conclusion is that the isomorphous strontium impurity is structurally sensitive element for calcium phosphate. It was determined that the beginning of strontium desorption corresponds to the beginning of transformation of the TCP - HAP (author)

  17. Phosphate Inhibits Acetotrophic Methanogenesis on Rice Roots

    OpenAIRE

    Conrad, Ralf; Klose, Melanie; Claus, Peter

    2000-01-01

    The contribution of acetate- and H2/CO2-dependent methanogenesis to total CH4 production was determined in excised washed rice roots by radiolabeling, methyl fluoride inhibition, and stable carbon isotope fractionation. Addition of ≥20 mM phosphate inhibited methanogenesis, which then was exclusively from H2/CO2. Otherwise, acetate contributed about 50 to 60% of the total methanogenesis, demonstrating that phosphate specifically inhibited acetotrophic methanogens on rice roots.

  18. Electron transfer in dinucleoside phosphate anions

    International Nuclear Information System (INIS)

    The electron transfer reaction within various dinucleoside phosphate radical anions has been investigated by ESR spectroscopy and pulse radiolysis. In the ESR work electrons are produced by photolysis of K4Fe(CN)6 in a 12 M LiCl glass at 770K. Upon photobleaching the electrons react with the dinucleoside phosphate to form the anion radical. The anions of the four DNA nucleosides were also produced and their ESR spectra were appropriately weighted and summed by computer to simulate the spectra found for the dinucleoside phosphate anions. From the analysis the relative amounts of each of the nucleoside anions in the dinucleoside phosphate anion were determined. Evidence suggests the electron affinity of the pyrimidine bases are greater than the purine bases; however, the results are not sufficient to distinguish between the individual purine or pyrimidine. When dinucleoside phosphate anions containing thymidine are warmed, protonation occurs only on thymine to produce the well known ''thymyl'' spectrum. Pulse radiolysis experiments on individual nucleotides (TMP, dAMP), mixtures of these nucleotides and the dinucleoside phosphate, TdA, in aqueous solution at room temperature show that in the TdA anion electron transfer occurs from adenine to thymine, whereas no electron transfer is found for mixtures of individual nucleotides. Protonation is found to occur only on thymine in the TdA anion in agreement with the ESR results

  19. Phosphate rock costs, prices and resources interaction.

    Science.gov (United States)

    Mew, M C

    2016-01-15

    This article gives the author's views and opinions as someone who has spent his working life analyzing the international phosphate sector as an independent consultant. His career spanned two price hike events in the mid-1970's and in 2008, both of which sparked considerable popular and academic interest concerning adequacy of phosphate rock resources, the impact of rising mining costs and the ability of mankind to feed future populations. An analysis of phosphate rock production costs derived from two major industry studies performed in 1983 and 2013 shows that in nominal terms, global average cash production costs increased by 27% to $38 per tonne fob mine in the 30 year period. In real terms, the global average cost of production has fallen. Despite the lack of upward pressure from increasing costs, phosphate rock market prices have shown two major spikes in the 30 years to 2013, with periods of less volatility in between. These price spike events can be seen to be related to the escalating investment cost required by new mine capacity, and as such can be expected to be repeated in future. As such, phosphate rock price volatility is likely to have more impact on food prices than rising phosphate rock production costs. However, as mining costs rise, recycling of P will also become increasingly driven by economics rather than legislation. PMID:26412420

  20. Phosphate diabetes in patients with chronic fatigue syndrome.

    OpenAIRE

    Lorenzo, F.; Hargreaves, J.; Kakkar, V V

    1998-01-01

    Phosphate depletion is associated with neuromuscular dysfunction due to changes in mitochondrial respiration that result in a defect of intracellular oxidative metabolism. Phosphate diabetes causes phosphate depletion due to abnormal renal re-absorption of phosphate be the proximal renal tubule. Most of the symptoms presented by patients with phosphate diabetes such as myalgia, fatigue and mild depression, are also common in patients with chronic fatigue syndrome, but this differential diagno...

  1. Can features of phosphate toxicity appear in normophosphatemia?

    OpenAIRE

    Osuka, Satoko; Razzaque, Mohammed S.

    2012-01-01

    Phosphate is an indispensable nutrient for the formation of nucleic acids and the cell membrane. Adequate phosphate balance is a prerequisite for basic cellular functions ranging from energy metabolism to cell signaling. More than 85% of body phosphate is present in the bones and teeth. The remaining phosphate is distributed in various soft tissues, including skeletal muscle. A tiny amount, around 1% of total body phosphate, is distributed both in the extracellular fluids and within the cells...

  2. Phosphate separation and recovery from wastewater by novel electrodialysis.

    Science.gov (United States)

    Zhang, Yang; Desmidt, Evelyn; Van Looveren, Arnaud; Pinoy, Luc; Meesschaert, Boudewijn; Van der Bruggen, Bart

    2013-06-01

    Stimulated by the depletion of phosphate resources, phosphate recovery systems have been studied in recent years. The use of struvite reactors has proven to be an effective phosphate recovery process. However, the struvite reactor effluent still consists of an excessive amount of phosphate that cannot be recovered nor can be directly discharged. In this study, selectrodialysis (SED) was used to improve the efficiency of phosphate recovery from a struvite reactor: SED was implemented in such a way that phosphate from the effluent of an USAB (upflow anaerobic sludge blanket) reactor was transferred to the recycled effluent of a struvite reactor. Prior to the experiments, synthetic water with chloride and phosphate was used to characterize the efficiency of SED for phosphate separation. Results indicate that SED was successful in concentrating phosphate from the feed stream. The initial current efficiency reached 72%, with a satisfying (9 mmol L(-1)) phosphate concentration. In the experiments with the anaerobic effluent as the phosphate source for enrichment of the effluent of the struvite reactor, the phosphate flux was 16 mmol m(-2) h(-1). A cost evaluation shows that 1 kWh electricity can produce 60 g of phosphate by using a full scale stack, with a desalination rate of 95% on the feed wastewater. Finally, a struvite precipitation experiment shows that 93% of phosphate can be recovered. Thus, an integrated SED-struvite reactor process can be used to improve phosphate recovery from wastewater. PMID:23651001

  3. Relationship between Nitrite Reduction and Active Phosphate Uptake in the Phosphate-Accumulating Denitrifier Pseudomonas sp. Strain JR 12

    OpenAIRE

    Barak, Yoram; van Rijn, Jaap

    2000-01-01

    Phosphate uptake by the phosphate-accumulating denitrifier Pseudomonas sp. JR12 was examined with different combinations of electron and carbon donors and electron acceptors. Phosphate uptake in acetate-supplemented cells took place with either oxygen or nitrate but did not take place when nitrite served as the final electron acceptor. Furthermore, nitrite reduction rates by this denitrifier were shown to be significantly reduced in the presence of phosphate. Phosphate uptake assays in the pr...

  4. Solubilization of inorganic phosphate and production of organic acids by bacteria isolated from a Moroccan mineral phosphate deposit

    OpenAIRE

    Mardad, Illham; Serrano, Aurelio; Soukri, Abdelaziz

    2013-01-01

    Three efficient inorganic-phosphate solubilizing bacteria (PSB) were isolated from a phosphate rock deposit of a Moroccan mine. The phosphate solubilization index of these isolates, determined in National Botanical Research Institute's phosphate (NBRIP) medium supplemented with tribasic calcium phosphate, ranging from 2.8 to 4.4. The medium pH dropped from 7.0 to 3.5 units after growth under continuous agitation for seven days. PSB6, the most efficient PSB, closely related to Enterobacter hor...

  5. Conformation of lanthanides complexes of L-serine phosphate and ethanolamine phosphate in aqueous phase

    International Nuclear Information System (INIS)

    NMR paramagnetic shifts induced by rare earth cations lead to conformations of complexes in aqueous solution. A computer treatment is developped for complexes of L-serine phosphate and ethanolamine phosphate with lanthanides in acidic solution (pH=1 to 1.8). Angle and distance values are discussed with a hindered rotation about P-O1 bond

  6. Natural radioactivity in phosphate rock, phosphogypsum and phosphate fertilizers in Brazil

    International Nuclear Information System (INIS)

    Phosphate deposits are generally characterized by enhanced radionuclide concentrations compared to natural levels. The mining and processing of this phosphate ore redistribute radionuclides throughout the environment and introduce them into phosphoric acid and phosphogypsum. Phosphoric acid is the starting material for triple superphosphate (TSP), single superphosphate (SSP), monoammonium phosphate (MAP), diammonium phosphate (DAP), NPK fertilizers and di-calcium phosphate (DCP). Contents of natural radionuclides from thorium and uranium series, 226Ra, 210Pb and 228Ra, were measured in Brazilian igneous phosphate rock, phosphoric acid, phosphogypsum and phosphate fertilizer samples, using high-resolution gamma-spectrometry. Neutron activation analysis was used for the determination of U and Th in the same samples. The fertilizers samples which are derived directly from phosphoric acid, MAP and DAP, presented activity concentrations around the detection limits of the counting system for 226Ra (-1), for 228Ra (-1) and for 210Pb (-1). As for U and Th, the concentrations found in MAP and DAP are more significant, up to 374 and 250 Bq x kg-1, respectively. SSP, TSP and NPK, which are obtained by mixing phosphoric acid with different amounts of phosphate rock and NH3, presented higher concentrations of radionuclides, up to 871 Bq x kg-1 for 226Ra, 283 Bq x kg-1 for 228Ra, 1255 Bq x kg-1 for 210Pb, 413 Bq x kg-1 for U and 538 Bq x kg-1 for Th. (author)

  7. An autosomal glucose-6-phosphate dehydrogenase (hexose-6-phosphate dehydrogenase) polymorphism in human saliva.

    Science.gov (United States)

    Tan, S G; Ashton, G C

    1976-01-01

    Glucose-6-phosphate dehydrogenase (hexose-6-phosphate dehydrogenase) from human saliva has been demonstrated by the zymogram technique. Three phenotypes were found. Family and population studies suggested that these phenotypes are the products of an autosomal locus with two alleles Sgd-1 and Sgd-2. PMID:950237

  8. Biological Removal of Phosphate Using Phosphate Solubilizing Bacterial Consortium from Synthetic Wastewater: A Laboratory Scale

    Directory of Open Access Journals (Sweden)

    Dipak Paul

    2015-01-01

    Full Text Available Biological phosphate removal is an important process having gained worldwide attention and widely used for removing phosphorus from wastewater. The present investigation was aimed to screen the efficient phosphate solubilizing bacterial isolates and used to remove phosphate from synthetic wastewater under shaking flasks conditions. Pseudomonas sp. JPSB12, Enterobacter sp. TPSB20, Flavobacterium sp. TPSB23 and mixed bacterial consortium (Pseudomonas sp. JPSB12+Enterobacter sp. TPSB20+Flavobacterium sp. TPSB23 were used for the removal of phosphate. Among the individual strains, Enterobacter sp. TPSB20 was removed maximum phosphate (61.75% from synthetic wastewater in presence of glucose as a carbon source. The consortium was effectively removed phosphate (74.15-82.50% in the synthetic wastewater when compared to individual strains. The pH changes in culture medium with time and extracellular phosphatase activity (acid and alkaline were also investigated. The efficient removal of phosphate by the consortium may be due to the synergistic activity among the individual strains and phosphatase enzyme activity. The use of bacterial consortium in the remediation of phosphate contaminated aquatic environments has been discussed.

  9. Cloning and characterization of a glucose 6-phosphate/phosphate translocator from Oryza sativa

    Institute of Scientific and Technical Information of China (English)

    姜华武; 佃蔚敏; 刘非燕; 吴平

    2003-01-01

    Plastids of nongreen tissues import carbon as a source of biosynthetic pathways and energy, and glucose 6-phosphate is the preferred hexose phosphate taken up by nongreen plastids. A cDNA clone encoding glucose 6-phosphate/phosphate translocator (GPT) was isolated from a cDNA library of immature seeds of rice and named as OsGPT. The cDNA has one uninterrupted open reading frame encoding a 42 kDa polypeptide possessing transit peptide consisting of 70 amino acid residues. The OsGPT gene maps on chromosome 8 of rice and is linked to the quantitative trait locus for 1000-grain weight. The expression of OsGPT is mainly restricted to heterotrophic tissues. These results suggest that glucose 6-phosphate imported via GPT can be used for starch biosynthesis in rice nongreen plastids.

  10. Isolation and screening phosphate solubilizers from composts as biofertilizer

    International Nuclear Information System (INIS)

    Phosphate solubilizers are miroorganisms that able to solubilize insoluble inorganic phosphate compounds or hydrolyze organic phosphate to inorganic P. Therefore make the P to be available for plant and consequently enhance plant growth and yield. Recently, phosphate solubilizing microorganisms has been shown to play an important role in the biofertilizer industry. Fifty-one bacterial were isolated from eleven composts. Most of the phosphate solubilizers were isolated from natural farming composted compost and normal composting compost. This shows that both of these composts are more suitable to use for phosphate solubilizer isolation compare commercial composts. Fourteen of the isolates were found to be phosphate solubilizers. These isolates produced a clear zone on the phosphate agar plates, showing their potential as biofertilizer. AP3 was significantly produced the largest clear zone compared with other isolates. This indicates that isolate AP 3 could be a good phosphate solubilizer. Thus, their effectiveness in the greenhouse and field should be evaluated. (Author)

  11. Structural basis for phosphatidylinositol-phosphate biosynthesis

    Science.gov (United States)

    Clarke, Oliver B.; Tomasek, David; Jorge, Carla D.; Dufrisne, Meagan Belcher; Kim, Minah; Banerjee, Surajit; Rajashankar, Kanagalaghatta R.; Shapiro, Lawrence; Hendrickson, Wayne A.; Santos, Helena; Mancia, Filippo

    2015-10-01

    Phosphatidylinositol is critical for intracellular signalling and anchoring of carbohydrates and proteins to outer cellular membranes. The defining step in phosphatidylinositol biosynthesis is catalysed by CDP-alcohol phosphotransferases, transmembrane enzymes that use CDP-diacylglycerol as donor substrate for this reaction, and either inositol in eukaryotes or inositol phosphate in prokaryotes as the acceptor alcohol. Here we report the structures of a related enzyme, the phosphatidylinositol-phosphate synthase from Renibacterium salmoninarum, with and without bound CDP-diacylglycerol to 3.6 and 2.5 Å resolution, respectively. These structures reveal the location of the acceptor site, and the molecular determinants of substrate specificity and catalysis. Functional characterization of the 40%-identical ortholog from Mycobacterium tuberculosis, a potential target for the development of novel anti-tuberculosis drugs, supports the proposed mechanism of substrate binding and catalysis. This work therefore provides a structural and functional framework to understand the mechanism of phosphatidylinositol-phosphate biosynthesis.

  12. Phosphorylation of Kraft fibers with phosphate esters.

    Science.gov (United States)

    Shi, Ying; Belosinschi, Dan; Brouillette, François; Belfkira, Ahmed; Chabot, Bruno

    2014-06-15

    Phosphate esters, derived from two different long-chain aliphatic alcohols, were used as phosphorylating reagents for Kraft pulp fibers. High phosphorus contents and almost non-degraded fibers were obtained by following this pathway. The phosphorylation efficiency was influenced by the alkyl chain length of PEs since the phosphorus content in modified fibers was higher for the shorter chain reagent. Due to the heterogeneous reaction environment, the amount of grafted phosphorus was found to be almost three times higher at the surface than in the bulk of the fibers. Analyses also indicated that the phosphorus was bonded to fibers as a phosphate-like structure. Furthermore, the situation seemed to be different for the fiber surface where significant amounts of phosphorus were present in more complex structures like pyrophosphate or even oligo-phosphate. PMID:24721058

  13. Phosphate Phosphors for Solid-State Lighting

    CERN Document Server

    Shinde, Kartik N; Swart, H C; Park, Kyeongsoon

    2012-01-01

    The idea for this book arose out of the realization that, although excellent surveys and a phosphor handbook are available, there is no single source covering the area of phosphate based phosphors especially for lamp industry. Moreover, as this field gets only limited attention in most general books on luminescence, there is a clear need for a book in which attention is specifically directed toward this rapidly growing field of solid state lighting and its many applications. This book is aimed at providing a sound introduction to the synthesis and optical characterization of phosphate phosphor for undergraduate and graduate students as well as teachers and researchers. The book provides guidance through the multidisciplinary field of solid state lighting specially phosphate phosphors for beginners, scientists and engineers from universities, research organizations, and especially industry. In order to make it useful for a wide audience, both fundamentals and applications are discussed, together.

  14. Phosphates behaviours in conversion of FP chlorides

    International Nuclear Information System (INIS)

    The spent electrolyte of the pyroprocessing by metal electrorefining method should be considered for recycling after removal of fission products (FP) such as, alkali metals (AL), alkaline earth metals (ALE), and/or rare earth elements (REE), to reduce the volume of high-level radioactive waste. Among the various methods suggested for this purpose is precipitation by converting FP from chlorides to phosphates. Authors have been carrying out the theoretical analysis and experiment showing the behaviours of phosphate precipitates so as to estimate the feasibility of this method. From acquired results, it was found that AL except lithium and ALE are unlikely to form phosphate precipitates. However their conversion behaviours including REE were compatible with the theoretical analysis; in the case of LaPO4 as one of the REE precipitates, submicron-size particles could be observed while that of Li3PO4 was larger; the precipitates were apt to grow larger at higher temperature; etc.

  15. Removal of Phosphate from Aqueous Solution with Modified Bentonite

    Institute of Scientific and Technical Information of China (English)

    唐艳葵; 童张法; 魏光涛; 李仲民; 梁达文

    2006-01-01

    Bentonite combined with sawdust and other metallic compounds was used to remove phosphate from aqueous solutions in this study. The adsorption characteristics of phosphate on the modified bentonite were investigated, including the effects of temperature, adsorbent dosage, initial concentration of phosphate and pH on removal of phosphate by conducting a series of batch adsorption experiments. The results showed that 98% of phosphate removal rate was obtained since sawdust and bentonite used in this investigation were abundantly and locally available. It is concluded that modified bentonite is a relatively efficient, low cost and easily available adsorbent for the removal of phosphate from aqueous solutions.

  16. Performance of pineapple slips inoculated with diazotrophic phosphate-solubilizing bacteria and rock phosphate

    Directory of Open Access Journals (Sweden)

    Lílian Estrela Borges Baldotto

    2014-06-01

    Full Text Available Besides fixing N2, some diazotrophic bacteria or diazotrophs, also synthesize organic acids and are able to solubilize rock phosphates, increasing the availability of P for plants. The application of these bacteria to pineapple leaf axils in combination with rock phosphate could increase N and P availability for the crop, due to the bacterial activity of biological nitrogen fixation and phosphate solubilization. The objectives of this study were: (i to select and characterize diazotrophs able to solubilize phosphates in vitro and (ii evaluate the initial performance of the pineapple cultivars Imperial and Pérola in response to inoculation with selected bacteria in combination with rock phosphate. The experiments were conducted at Universidade Estadual do Norte Fluminense Darcy Ribeiro, in 2009. In the treatments with bacteria the leaf contents of N, P and K were higher than those of the controls, followed by an increase in plant growth. These results indicate that the combined application of diazotrophic phosphate-solubilizing bacteria Burkholderia together with Araxá rock phosphate can be used to improve the initial performance of pineapple slips.

  17. Phosphate starvation regulon of Salmonella typhimurium.

    OpenAIRE

    Foster, J. W.; Spector, M P

    1986-01-01

    Several phosphate-starvation-inducible (psi) genetic loci in Salmonella typhimurium were identified by fusing the lacZ gene to psi promoters by using the Mu d1 and Mu d1-8 bacteriophages. Although several different starvation conditions were examined, the psi loci responded solely to phosphate deprivation. A regulatory locus, psiR, was identified as controlling the psiC locus. The psiR locus did not affect the expression of the Escherichia coli phoA locus or any of the other psi loci described.

  18. Occupational Exposure in Ammonium Phosphate Fertilizer Plants

    International Nuclear Information System (INIS)

    Occupational exposures and activity concentrations have been assessed in two industrial plants producing mono-ammonium phosphate and di-ammonium phosphate fertilizers, located in south-western Spain. The annual effective doses received by the workers are below 1 mSv/a, with the contribution from external exposure being similar to that from internal exposure. The dose contribution from inhalation of dust has been estimated to be about 0.12 mSv/a, while the 222Rn concentrations inside the plants are of no concern. Consequently, no additional radiation protection measures need to be taken to protect the workers in these facilities. (author)

  19. Calcium phosphate ceramics in drug delivery

    Science.gov (United States)

    Bose, Susmita; Tarafder, Solaiman; Edgington, Joe; Bandyopadhyay, Amit

    2011-04-01

    Calcium phosphate (CaP) particulates, cements and scaffolds have attracted significant interest as drug delivery vehicles. CaP systems, including both hydroxyapaptite and tricalcium phosphates, possess variable stoichiometry, functionality and dissolution properties which make them suitable for cellular delivery. Their chemical similarity to bone and thus biocompatibility, as well as variable surface charge density contribute to their controlled release properties. Among specific research areas, nanoparticle size, morphology, surface area due to porosity, and chemistry controlled release kinetics are the most active. This article discusses CaP systems in their particulate, cements, and scaffold forms for drug, protein, and growth factor delivery toward orthopedic and dental applications.

  20. Potentially Prebiotic Syntheses of Condensed Phosphates

    Science.gov (United States)

    Keefe, Anthony D.; Miller, Stanley L.

    1996-01-01

    In view of the importance of a prebiotic source of high energy phosphates, we have investigated a number of potentially prebiotic processes to produce condensed phosphates from orthophosphate and cyclic trimetaphosphate from tripolyphosphate. The reagents investigated include polymerizing nitriles, acid anhydrides, lactones, hexamethylene tetramine and carbon suboxide. A number of these processes give substantial yields of pyrophosphate from orthophosphate and trimetaphosphate from tripolyphosphate. Although these reactions may have been applicable in local areas, they are not sufficiently robust to have been of importance in the prebiotic open ocean.

  1. Xenobiotic conjugation with phosphate - a metabolic rarity.

    Science.gov (United States)

    Mitchell, Stephen C

    2016-08-01

    1. Although not unknown, the conjugation of a xenobiotic with phosphate appears a rarity amongst the routes available for foreign compound metabolism. This is especially true in mammals and may be somewhat surprising as conjugation with sulphate, a seemingly similar moiety, is commonplace. 2. Information from the literature, where xenobiotic phosphate conjugates have been described or suggested, has been collated and presented in this article. By bringing together this diverse material, hopefully interest will be generated in this unusual xenobiotic reaction, and perhaps further research undertaken to better understand and delineate the reasons for its relative absence from the xenobiotic scene. PMID:26611118

  2. Synthesis and characterization of porous calcium phosphate

    International Nuclear Information System (INIS)

    The porous calcium phosphate was prepared by the continuous precipitation method using Ca(NO3)2.4H2O and NH4H2PO4 salts. The synthesized material was structurally and superficially characterized using the XRD, BET, IR TGA and SEM techniques. The obtained inorganic material was identified as calcium phosphate that presents a great specific area for what can be efficiently used as adsorbent material for adsorption studies in the radioactive wastes treatment present in aqueous solution. (Author)

  3. Evaluation of intestinal phosphate binding to improve the safety profile of oral sodium phosphate bowel cleansing.

    Directory of Open Access Journals (Sweden)

    Stef Robijn

    Full Text Available Prior to colonoscopy, bowel cleansing is performed for which frequently oral sodium phosphate (OSP is used. OSP results in significant hyperphosphatemia and cases of acute kidney injury (AKI referred to as acute phosphate nephropathy (APN; characterized by nephrocalcinosis are reported after OSP use, which led to a US-FDA warning. To improve the safety profile of OSP, it was evaluated whether the side-effects of OSP could be prevented with intestinal phosphate binders. Hereto a Wistar rat model of APN was developed. OSP administration (2 times 1.2 g phosphate by gavage with a 12h time interval induced bowel cleansing (severe diarrhea and significant hyperphosphatemia (21.79 ± 5.07 mg/dl 6h after the second OSP dose versus 8.44 ± 0.97 mg/dl at baseline. Concomitantly, serum PTH levels increased fivefold and FGF-23 levels showed a threefold increase, while serum calcium levels significantly decreased from 11.29 ± 0.53 mg/dl at baseline to 8.68 ± 0.79 mg/dl after OSP. OSP administration induced weaker NaPi-2a staining along the apical proximal tubular membrane. APN was induced: serum creatinine increased (1.5 times baseline and nephrocalcinosis developed (increased renal calcium and phosphate content and calcium phosphate deposits on Von Kossa stained kidney sections. Intestinal phosphate binding (lanthanum carbonate or aluminum hydroxide was not able to attenuate the OSP induced side-effects. In conclusion, a clinically relevant rat model of APN was developed. Animals showed increased serum phosphate levels similar to those reported in humans and developed APN. No evidence was found for an improved safety profile of OSP by using intestinal phosphate binders.

  4. Effect of aluminium phosphate as admixture on oxychloride cement

    Indian Academy of Sciences (India)

    M P S Chandrawat; R N Yadav

    2000-02-01

    The effect of admixing of aluminium phosphate on oxychloride cement in the matrix has been investigated. It is shown that aluminium phosphate retards the setting process of the cement and improves water-tightness.

  5. Durability of phosphate-selective CHEMFETs

    NARCIS (Netherlands)

    Wroblewski, Wojciech; Wojciechowski, Kamil; Dybko, Artur; Brzozka, Zbigniew; Egberink, Richard J.M.; Snellink-Ruel, Bianca H.M.; Reinhoudt, David N.

    2001-01-01

    Lipophilic uranyl salophenes derivatives I and II were used as ionophores in membranes of phosphate-selective CHEMFETs. High selectivity for H2PO4− over other anions was obtained for these sensors. The influence of the ionophore structure on the sensor durability was investigated. CHEMFETs based on

  6. Thermochemical investigations on uranyl phosphates and arsenates

    International Nuclear Information System (INIS)

    The results are described of a study of the thermochemical stability of anhydrous uranyl phosphates and arsenates. A number of aspects of chemical technological importance are indicated in detail. The synthesized anhydrous uranyl phosphates and arsenates were very hygroscopic, so that experiments on these compounds had to be carried out under moisture-free conditions. Further characterisation of these compounds are given, including a study of their thermal stabilities and phase relations. The uranyl phosphates reduced reversibly at temperatures of the order of 1100 to 16000C. This makes it possible to express their relative stabilities quantitatively, in terms of the oxygen pressures of the reduction reactions. The thermal decomposition of uranyl arsenates did not occur by reduction, as for the phosphates, but by giving off arsenic oxide vapour. The results of measurements of enthalpies of solution led to the determination of the enthalpies of formation, heat capacity and the standard entropies of the uranyl arsenates. The thermochemical functions at high-temperatures could consequently be calculated. Attention is paid to the possible formation of uranium arsenates, whose uranium has a valency lower than six, hitherto not reported in literature. It was not possible to prepare arsenates of tetravalent uranium. However, three new compounds were observed, one of these, UAsO5, was studied in some detail. (Auth.)

  7. Biodegradation of tert-butylphenyl diphenyl phosphate

    International Nuclear Information System (INIS)

    The biodegradation of tert-butylphenyl diphenyl phosphate (BPDP) was examined in microcosms containing sediment and water from five different ecosystems as part of studies to elucidate the environmental fate of phosphate ester flame retardants. Biodegradation of [14C]BPDP was monitored in the environmental microcosms by measuring the evolution of 14CO2. Over 37% of BPDP was mineralized after 8 weeks in microcosms from an ecosystem which had chronic exposure to agricultural chemicals. In contrast, only 1.7% of BPDP was degraded to 14CO2 in samples collected from a noncontaminated site. The exposure concentration of BPDP affected the percentage which was degraded to 14CO2 in microcosms from the two most active ecosystems. Mineralization was highest at a concentration of 0.1 mg of BPDP and was inhibited with 10- and 100-fold higher concentrations of BPDP. The authors observed adaptive increases in both microbial populations and phosphoesterase enzymes in some sediments acclimated to BPDP. Chemical analyses of the residues in the microcosms indicated undegraded BPDP and minor amounts of phenol, tert-butylphenol, diphenyl phosphate, and triphenyl phosphate as biodegradation products. These data suggest that the microbial degradation of BPDP results from at least three catabolic processes and is highest when low concentrations of BPDP are exposed to sediment microorganisms of eutrophic ecosystems which have high phosphotri- and diesterase activities and previous exposure to anthropogenic chemicals

  8. Three-dimensionally Perforated Calcium Phosphate Ceramics

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Porous calcium phosphate ceramics were produced by compression molding using a special mold followed by sintering. The porous calcium phosphate ceramics have three-dimensional and penetrated open pores380-400μm in diameter spaced at intervals of 200μm. The layers of the linear penetration pores alternately lay perpendicular to pore direction. The porosity was 59%-65% . The Ca/P molar ratios of the porous calcium phosphate ceramics range from 1.5 to 1.85. A binder containing methyl cellulose was most effective for preparing the powder compact among vinyl acetate, polyvinyl alcohol, starch, stearic acid, methyl cellulose and their mixtures. Stainless steel, polystyrene, nylon and bamboo were used as the long columnar male dies for the penetrated open pores. When polystyrene, nylon and bamboo were used as the long columnar male dies, the dies were burned out during the sintering process. Using stainless steel as the male dies with the removal of the dies before heat treatment resulted in a higher level of densification of the calcium phosphate ceramic.

  9. Thermochemical investigations on uranyl phosphates and arsenates

    International Nuclear Information System (INIS)

    Results are described of a study of the thermochemical stability of anhydrous phosphates and arsenates. The results of phase studies deal with compound formation and characterization, coexisting phases and limiting physical or chemical properties. The uranyl phosphates evolve oxygen at higher temperatures and the arsenates lose arsenic oxide vapour. These phenomena give the possibility to describe their thermodynamic stabilities. Thus oxygen pressures of uranyl phosphates have been measured using a static, non-isothermal method. Having made available the pure anhydrous compounds in the course of this investigation, molar thermodynamic quantities have been measured as well. These include standard enthalpies of formation from solution calorimetry and high-temperature heat-capacity functions derived from enthalpy increments measured. Some attention is given to compounds with uranium in valencies lower than six which have been met during the investigation. An evaluation is made of the thermodynamics of the compounds studied, to result in tabulized high-temperature thermodynamic functions. Relative stabilities within the systems are discussed and comparisons of the uranyl phosphates and the arsenates are made. (Auth.)

  10. TUCS/phosphate mineralization of actinides

    Energy Technology Data Exchange (ETDEWEB)

    Nash, K.L. [Argonne National Lab., IL (United States)

    1997-10-01

    This program has as its objective the development of a new technology that combines cation exchange and mineralization to reduce the concentration of heavy metals (in particular actinides) in groundwaters. The treatment regimen must be compatible with the groundwater and soil, potentially using groundwater/soil components to aid in the immobilization process. The delivery system (probably a water-soluble chelating agent) should first concentrate the radionuclides then release the precipitating anion, which forms thermodynamically stable mineral phases, either with the target metal ions alone or in combination with matrix cations. This approach should generate thermodynamically stable mineral phases resistant to weathering. The chelating agent should decompose spontaneously with time, release the mineralizing agent, and leave a residue that does not interfere with mineral formation. For the actinides, the ideal compound probably will release phosphate, as actinide phosphate mineral phases are among the least soluble species for these metals. The most promising means of delivering the precipitant would be to use a water-soluble, hydrolytically unstable complexant that functions in the initial stages as a cation exchanger to concentrate the metal ions. As it decomposes, the chelating agent releases phosphate to foster formation of crystalline mineral phases. Because it involves only the application of inexpensive reagents, the method of phosphate mineralization promises to be an economical alternative for in situ immobilization of radionuclides (actinides in particular). The method relies on the inherent (thermodynamic) stability of actinide mineral phases.

  11. Formation of plutonium phosphates in chloride melts

    Energy Technology Data Exchange (ETDEWEB)

    Burnaeva, A.A.; Kryukova, A.I.; Kazanstev, G' N.; Skiba, O.V.; Korshunov, I.A.

    1984-01-01

    Introduction of sodium- and potassium phosphates Na/sub 3/PO/sub 4/ and K/sub 3/PO/sub 4/ in the PuCl/sub 3/-NaCl, PuCl/sub 3/-KCl melts results in reduction of plutonium amount in the liquid phase. Low-soluble plutonium (3) phosphates, of assumed Na/sub 3/Pu/sub 2/ composition (PO/sub 4/)/sub 3/ are transported into the solid phase. Using the methods of radiographical and radiometric analyses the phases of plutonium phosphates separated by precipitation from chloride melt and also prepared from PuO/sub 2/ and NaH/sub 2/PO/sub 4/ at 1200 deg C are investigated. Their solubility in the NaCl-KCl melt and stability to these melts during a long-term contact, and also under the effect of CCl/sub 4/ are evaluated. The data are compared with similar data for thorium-, uranium-, americium-, curium-, zirconium-, rare earth phosphates.

  12. Iron phosphate glass containing simulated fast reactor waste: Characterization and comparison with pristine iron phosphate glass

    International Nuclear Information System (INIS)

    Detailed characterization was carried out on an iron phosphate glass waste form containing 20 wt.% of a simulated nuclear waste. High temperature viscosity measurement was carried out by the rotating spindle method. The Fe3+/Fe ratio and structure of this waste loaded iron phosphate glass was investigated using Mössbauer and Raman spectroscopy respectively. Specific heat measurement was carried out in the temperature range of 300–700 K using differential scanning calorimeter. Isoconversional kinetic analysis was employed to understand the crystallization behavior of the waste loaded iron phosphate glass. The glass forming ability and glass stability of the waste loaded glass were also evaluated. All the measured properties of the waste loaded glass were compared with the characteristics of pristine iron phosphate glass

  13. Transfer of Some Major and Trace Elements From Phosphate Rock to Super-Phosphate Fertilizers

    International Nuclear Information System (INIS)

    This study assesses the transfer of some major and trace elements from phosphate rock (PR) to single (SSP) and triple (TSP) superphosphate fertilizers. Samples from a fertilizer plant and local market were collected and analyzed using inductively coupled plasma spectrometer. Cluster analysis indicated that the inner-relationship among the concentration of the elements in PR, SSP, and TSP are different. Only one element (Mo) has concentration in SSP higher than phosphate rock. The production process of these two types of superphosphate leads to transfer higher portion of Mn, B, Cu, Mo, Sr, and V present in the phosphate rock to SSP than TSP. The potentially hazardous element Cd is also transmitted more to SSP than TSP, and Cr is equally transferred to both types. The mean elemental concentrations normalized to the percentage of P2O5 demonstrate that for most elements they are the higher concentrations in SSP are linked to the phosphate contents

  14. Removing and Recovering Phosphate from Poultry Wastewater Using Amorphous Ceramics

    OpenAIRE

    Youhui Xie; Qin Li; Xianzhi Zhao; Yi Luo; Yangming Wang; Xiangwei Peng; Qigui Wang; Jian Su; Yin Lu

    2014-01-01

    A novel and effective technique for phosphate from poultry wastewater was developed using amorphous ceramics. Amorphous ceramics, which showed high performance for phosphate removal and recovery from poultry wastewater, were synthesized using unlimitedly available, inexpensive materials such as silica fume and lime. Dissolved phosphate in poultry wastewater can be deposited as a solid on the surface of amorphous ceramics. Phosphate content on the surface of amorphous ceramics could reach 14.2...

  15. Akt2/PKBbeta-sensitive regulation of renal phosphate transport

    OpenAIRE

    Kempe, D S; Ackermann, T F; Boini, K M; Klaus, F; Umbach, A T; Dërmaku-Sopjani, M; Judenhofer, M S; Pichler, B J; Capuano, P.; Stange, G.; Wagner, C. A.; Birnbaum, M J; Pearce, D.; Föller, M; Lang, F.

    2010-01-01

    AIM: The protein kinase B (PKB)/Akt is known to stimulate the cellular uptake of glucose and amino acids. The kinase is expressed in proximal renal tubules. The present study explored the influence of Akt/PKB on renal tubular phosphate transport. METHODS: The renal phosphate transporter NaPi-IIa was expressed in Xenopus oocytes with or without PKB/Akt and Na(+) phosphate cotransport determined using dual electrode voltage clamp. Renal phosphate excretion was determined in Akt2/PKBbeta knockou...

  16. The stability mechanisms of an injectable calcium phosphate ceramic suspension.

    OpenAIRE

    Fatimi, Ahmed; Tassin, Jean-François; Axelos, Monique; Weiss, Pierre

    2010-01-01

    Calcium phosphate ceramics are widely used as bone substitutes in dentistry and orthopedic applications. For minimally invasive surgery an injectable calcium phosphate ceramic suspension (ICPCS) was developed. It consists in a biopolymer (hydroxypropylmethylcellulose: HPMC) as matrix and bioactive calcium phosphate ceramics (biphasic calcium phosphate: BCP) as fillers. The stability of the suspension is essential to this generation of "ready to use" injectable biomaterial. But, during storage...

  17. Biological Effects of Phosphate on Fibroblast-Like Synoviocytes

    OpenAIRE

    Yubo Sun; Mauerhan, David R.; Deepthi Chaturvedi; Hanley, Edward N; Gruber, Helen E.

    2012-01-01

    This study sought to examine the expression of genes implicated in phosphate transport and pathological calcification in osteoarthritis (OA) and rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS) and investigate the biological effects of phosphate. Results revealed that several genes, which were implicated in phosphate transport and pathological calcification, were differentially expressed in OA FLS and RA FLS. Phosphate stimulated the expression of matrix metalloproteinse-1, matrix...

  18. Substitution of calcium by strontium within selected calcium phosphates

    Science.gov (United States)

    Rokita, E.; Hermes, C.; Nolting, H.-F.; Ryczek, J.

    1993-06-01

    Sr incorporation in the molecules of amorphous calcium phosphate, apatitic tricalcium phosphate, hydroxyapatite, octacalcium phosphate and dicalcium phosphate dihydrate was investigated. The concentration of Sr ranged from 225 to 1010 μ g / g, i.e. it overlapped with the physiological range of Sr concentrations in human bone. The leading experimental technique was extended X-ray absorption fine structure (EXAFS) at the Sr K edge. Results of these studies demonstrated the following: (1) Sr incorporation in the calcium phosphates is compound-dependent, (2) the coordination of incorporated Sr atoms in the Ca-P molecules is similar to that of Ca atoms, but interatomic distances are ≈0.015 nm larger, (3) in apatitic tricalcium phosphate, hydroxyapatite and octacalcium phosphate lattices Sr atoms may occupy selected Ca sites, which was not the case for dicalcium phosphate dihydrate, (4) in the apatite lattice Sr atoms are coordinated by 6 PO 4 tetrahedrals and (5) EXAFS spectra at the K edge of the incorporated Sr may be used to distinguish the structures of amorphous calcium phosphate, dicalcium phosphate dihydrate as well as apatite and its derivatives (apatitic tricalcium phosphate, octacalcium phosphate).

  19. 21 CFR 182.6215 - Monobasic calcium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Monobasic calcium phosphate. 182.6215 Section 182.6215 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED....6215 Monobasic calcium phosphate. (a) Product. Monobasic calcium phosphate. (b) Conditions of use....

  20. 21 CFR 582.1781 - Sodium aluminum phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium aluminum phosphate. 582.1781 Section 582.1781 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Additives § 582.1781 Sodium aluminum phosphate. (a) Product. Sodium aluminum phosphate. (b) Conditions...

  1. 21 CFR 522.1883 - Prednisolone sodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Prednisolone sodium phosphate. 522.1883 Section... § 522.1883 Prednisolone sodium phosphate. (a) Specifications. Each milliliter of solution contains 20 milligrams (mg) prednisolone sodium phosphate (equivalent to 14.88 mg of prednisolone). (b) Sponsor. See...

  2. 21 CFR 182.1781 - Sodium aluminum phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium aluminum phosphate. 182.1781 Section 182.1781 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Food Substances § 182.1781 Sodium aluminum phosphate. (a) Product. Sodium aluminum phosphate....

  3. 21 CFR 182.6085 - Sodium acid phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium acid phosphate. 182.6085 Section 182.6085 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD... Sodium acid phosphate. (a) Product. Sodium acid phosphate. (b) Conditions of use. This substance...

  4. 21 CFR 582.6215 - Monobasic calcium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Monobasic calcium phosphate. 582.6215 Section 582.6215 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED....6215 Monobasic calcium phosphate. (a) Product. Monobasic calcium phosphate. (b) Conditions of use....

  5. 21 CFR 582.6085 - Sodium acid phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium acid phosphate. 582.6085 Section 582.6085 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Sodium acid phosphate. (a) Product. Sodium acid phosphate. (b) Conditions of use. This substance...

  6. Sodium-dependent phosphate transporters in osteoclast differentiation and function

    OpenAIRE

    Giuseppe Albano; Matthias Moor; Silvia Dolder; Mark Siegrist; Wagner, Carsten A.; Jürg Biber; Nati Hernando; Willy Hofstetter; Olivier Bonny; Fuster, Daniel G

    2015-01-01

    Osteoclasts are multinucleated bone degrading cells. Phosphate is an important constituent of mineralized bone and released in significant quantities during bone resorption. Molecular contributors to phosphate transport during the resorptive activity of osteoclasts have been controversially discussed. This study aimed at deciphering the role of sodium-dependent phosphate transporters during osteoclast differentiation and bone resorption. Our studies reveal RANKL-induced differential expressio...

  7. 21 CFR 582.5697 - Riboflavin-5-phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Riboflavin-5-phosphate. 582.5697 Section 582.5697 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5697 Riboflavin-5-phosphate. (a) Product. Riboflavin-5-phosphate. (b) Conditions of...

  8. Natural radioactivity in the environment: the Florida phosphate study

    International Nuclear Information System (INIS)

    Some topics discussed are: effects of phosphate mining on public health and the environment; concentrations of uranium and daughter products in phosphate ore; investigations of phosphate mining areas by the Florida Division of Health; development of an instrument for aerial survey of background radiation; evaluation of drinking water supplies; and use of waste products from mining operations for construction material

  9. 21 CFR 520.1804 - Piperazine phosphate capsules.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Piperazine phosphate capsules. 520.1804 Section... phosphate capsules. (a) Specifications. Each capsule contains 120, 300, or 600 milligrams of piperazine phosphate monohydrate. (b) Sponsor. See No. 051311 in § 510.600(c) of this chapter. (c) Conditions of...

  10. 21 CFR 520.2380f - Thiabendazole, piperazine phosphate powder.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Thiabendazole, piperazine phosphate powder. 520....2380f Thiabendazole, piperazine phosphate powder. (a) Specifications. Each ounce of water dispersible powder contains 6.67 grams of thiabendazole and 8.33 grams of piperazine (as piperazine phosphate)....

  11. 40 CFR 721.10046 - Polyaromatic amine phosphate (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Polyaromatic amine phosphate (generic... Specific Chemical Substances § 721.10046 Polyaromatic amine phosphate (generic). (a) Chemical substance and... amine phosphate (PMN P-02-747) is subject to reporting under this section for the significant new...

  12. 40 CFR 721.5980 - Dialkyl phosphorodithioate phosphate compounds.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Dialkyl phosphorodithioate phosphate... Specific Chemical Substances § 721.5980 Dialkyl phosphorodithioate phosphate compounds. (a) Chemical... as dialkyl phosphorodithioate phosphate compounds (P-90-1642 through 1649) are subject to...

  13. 21 CFR 522.1244 - Levamisole phosphate injection.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Levamisole phosphate injection. 522.1244 Section... § 522.1244 Levamisole phosphate injection. (a) Specifications. Each milliliter of sterile aqueous solution contains levamisole phosphate equivalent to 136.5 or 182 milligrams of levamisole...

  14. The Oxygen Isotopic Composition of Phosphate: A Tracer for Phosphate Sources and Cycling

    International Nuclear Information System (INIS)

    Phosphorus (P) is a limiting macro-nutrient for primary productivity and anthropogenic P-loading to aquatic ecosystems is one of the leading causes of eutrophication in many ecosystems throughout the world. Because P has only one stable isotope, traditional isotope techniques are not possible for tracing sources and cycling of P in aquatic systems. However, much of the P in nature is bonded to four oxygen (O) atoms as orthophosphate (PO43-). The P-O bonds in orthophosphate are strongly resistant to inorganic hydrolysis and do not exchange oxygen with water without biological mediation (enzyme-mediated recycling). Thus, the oxygen isotopic composition of dissolved inorganic phosphate (δ18Op) may be used as a tracer for phosphate sources and cycling in aquatic ecosystems. Recently, several studies have been conducted utilizing δ18Op as a tracer for phosphate sources and cycling in various aquatic environments. Specifically, work to date indicates that δ18Op is useful for determining sources of phosphate to aquatic systems if these sources have unique isotopic signatures and phosphate cycling within the system is limited compared to input fluxes. In addition, because various processes imprint specific fractionation effects, the δ18Op tracer can be utilized to determine the degree of phosphorous cycling and processing through the biomass. This chapter reviews several of these studies and discusses the potential to utilize the δ18Op of phosphate in rivers and streams. (author)

  15. Phosphate Rock Fertilizer in Acid Soil:Comparing Phosphate Extraction Methods for Measuring Dissolution

    Institute of Scientific and Technical Information of China (English)

    T.S.ANSUMANA-KAWA; WANGGUANGHUO

    1998-01-01

    Three phosphate extraction methods were used to investigate the dissolution,availability and transfo-mation of Kunyang phosphate rock(KPR) in two surface acid soils.Dissolution was determined by measuring the increase in the amounts of soluble and adsorbed inorganic phosphate fractions,and did not differ signifi-cantly among the three methods.Significant correlations were obtained among P fractions got by the three extraction methods.Dissolution continued until the end of the 90-day incubation period.At the end of the period,much of the applied phosphate recovered in both soils were in the Al- and Fe-P or in the hydroxide-and bicarbonate-extractable inorganic P fractions.The dissolution of KPR in the two soils was also similar: increased addition of phosphate rock resulted in decreased dissolution.The similarity in the order and extent of dissolution in the two soils was probably due to the similarity in each soil of several factors that are known to influence phosphate rock dissolution,namely low CEC,pH,P level,and base status;and high clay and free iron and aluminum oxide contents.The results suggested that KPR could be an aternative P source in the soils are not limiting.

  16. Microbial electrolysis cell accelerates phosphate remobilisation from iron phosphate contained in sewage sludge.

    Science.gov (United States)

    Fischer, Fabian; Zufferey, Géraldine; Sugnaux, Marc; Happe, Manuel

    2015-01-01

    Phosphate was remobilised from iron phosphate contained in digested sewage sludge using a bio-electric cell. A significant acceleration above former results was caused by strongly basic catholytes. For these experiments a dual chambered microbial electrolysis cell with a small cathode (40 mL) and an 80 times larger anode (2.5 L) was equipped with a platinum sputtered reticulated vitreous carbon cathode. Various applied voltages (0.2-6.0 V) generated moderate to strongly basic catholytes using artificial waste water with pH close to neutral. Phosphate from iron phosphate contained in digested sewage sludge was remobilised most effectively at pH ∼13 with up to 95% yield. Beside minor electrochemical reduction, hydroxyl substitution was the dominating remobilisation mechanism. Particle-fluid kinetics using the "shrinking core" model allowed us to determine the reaction controlling step. Reaction rates changed with temperature (15-40 °C) and an activation energy of Ea = 55 kJ mol(-1) was found. These analyses indicated chemical and physical reaction control, which is of interest for future scale-up work. Phosphate remobilisation rates increased significantly, yields doubled and recovered PO4(3-) concentrations increased four times using a task specific bio-electric system. The result is a sustainable process for decentralized phosphate mining and a green chemical base generator useful also for many other sustainable processing needs. PMID:25407335

  17. Phosphate and Vascular Calcification: Emerging Role of the Sodium-Dependent Phosphate Cotransporter PiT-1

    OpenAIRE

    Lau, Wei Ling; Festing, Maria H; Giachelli, Cecilia M.

    2010-01-01

    Elevated serum phosphate is a risk factor for vascular calcification and cardiovascular events in kidney disease as well as in the general population. Elevated phosphate levels drive vascular calcification, in part, by regulating vascular smooth muscle cell (VSMC) gene expression, function, and fate. The type III sodium-dependent phosphate cotransporter, PiT-1, is necessary for phosphate-induced VSMC osteochondrogenic phenotype change and calcification, and has recently been shown to have une...

  18. Ribose-5-Phosphate Biosynthesis in Methanocaldococcus jannaschii Occurs in the Absence of a Pentose-Phosphate Pathway

    OpenAIRE

    Grochowski, Laura L.; Xu, Huimin; White, Robert H.

    2005-01-01

    Recent work has raised a question as to the involvement of erythrose-4-phosphate, a product of the pentose phosphate pathway, in the metabolism of the methanogenic archaea (R. H. White, Biochemistry 43:7618-7627, 2004). To address the possible absence of erythrose-4-phosphate in Methanocaldococcus jannaschii, we have assayed cell extracts of this methanogen for the presence of this and other intermediates in the pentose phosphate pathway and have determined and compared the labeling patterns ...

  19. Purification and characterization of ribitol-5-phosphate and xylitol-5-phosphate dehydrogenases from strains of Lactobacillus casei.

    OpenAIRE

    Hausman, S Z; London, J

    1987-01-01

    A simple three-step procedure is described which yields electrophoretically homogeneous preparations of ribitol-5-phosphate dehydrogenase and xylitol-5-phosphate dehydrogenase. The former enzyme is a 115,000-molecular-weight protein composed of two subunits of identical size and is specific for its substrate, ribitol. The xylitol-5-phosphate dehydrogenase exists as a tetrameric protein with a molecular weight of 180,000; this enzyme oxidizes the phosphate esters of both xylitol and D-arabitol...

  20. Proton/Phosphate Stoichiometry in Uptake of Inorganic Phosphate by Cultured Cells of Catharanthus roseus (L.) G. Don

    Science.gov (United States)

    Sakano, Katsuhiro

    1990-01-01

    Upon absorption of phosphate, cultured cells of Catharanthus roseus (L.) G. Don caused a rapid alkalinization of the medium in which they were suspended. The alkalinization continued until the added phosphate was completely exhausted from the medium, at which time the pH of the medium started to drop sharply toward the original pH value. Phosphate exposure caused the pH of the medium to increase from pH 3.5 to values as high as 5.8, while the rate of phosphate uptake was constant throughout (10-17 micromoles per hour per gram fresh weight). This indicates that no apparent pH optimum exists for the phosphate uptake by the cultured cells. The amount of protons cotransported with phosphate was calculated from the observed pH change up to the maximum alkalinization and the titration curve of the cell suspension. Proton/phosphate transport stoichiometry ranged from less than unity to 4 according to the amount of phosphate applied. At low phosphate doses, the stoichiometries were close to 4, while at high phosphate doses, smaller stoichiometries were observed. This suggests that, at high phosphate doses, activation of the proton pump is induced by the longer lasting proton influx acidifying the cytoplasm. The increased H+ efflux due to the proton pump could partially compensate protons taken up via the proton-phosphate cotransport system. Thus, the H+/H2PO4− stoichiometry of the cotransport is most likely to be 4. PMID:16667491

  1. Glycochenodeoxycholic acid inhibits calcium phosphate precipitation in vitro by preventing the transformation of amorphous calcium phosphate to calcium hydroxyapatite.

    OpenAIRE

    Qiu, S M; Wen, G.; Hirakawa, N; Soloway, R D; Hong, N K; Crowther, R S

    1991-01-01

    Calcium hydroxyapatite can be a significant component of black pigment gallstones. Diverse molecules that bind calcium phosphate inhibit hydroxyapatite precipitation. Because glycine-conjugated bile acids, but not their taurine counterparts, bind calcium phosphate, we studied whether glycochenodeoxycholic acid inhibits calcium hydroxyapatite formation. Glycochenodeoxycholic acid (2 mM) totally inhibited transformation of amorphous calcium phosphate microprecipitates to macroscopic crystalline...

  2. Seed selections for crystallization of calcium phosphate for phosphorus recovery

    Institute of Scientific and Technical Information of China (English)

    SONG Yong-hui; Dietfried DONNERT; Ute BERG; Peter G. WEIDLER; Rolf NUEESCH

    2007-01-01

    Seed induces and promotes the crystallization of calcium phosphate, and acts as carrier of the recovered phosphorus (P). In order to select suitable seed for P recovery from wastewater, three seeds including Apatite (AP), Juraperle (JP) and phosphate-modified Juraperle (M-JP) were tested and compared. Batch and fixed-bed column experiments of seeded crystallization of calcium phosphate were undertaken by using synthetic wastewater with 10 mg/L P phosphate. It shows that AP has bad enduring property in the crystallization process, while JP has better performance for multiple uses, and M-JP is a hopeful seed for P recovery by crystallization of calcium phosphate.

  3. [Identification and determination of phosphates in dairy products].

    Science.gov (United States)

    Kirst, E

    1985-01-01

    This paper outlines the thin-layer chromatographic separation of condensed phosphates on polyamide-starch layers with subsequent digestion of the spots and photometric identification of the phosphates. With cheese and condensed milk the preparation of samples is carried out by isolation of the phosphate solution after protein precipitation by trichloroacetic acid. With pure phosphate solutions a recovery rate of 95.9% +/- 3.1% was established, whereas the recovery rate of added phosphate from processed cheese and condensed milk was 82.7% +/- 5.9%. PMID:4022105

  4. Prevention of radioactive contamination in the manufacture of phosphate fertilizers

    International Nuclear Information System (INIS)

    In this work was studied the separation of uranium from the phosphate rock to decrease the level of radioactivity in the phosphate fertilizers, this prevents the redistribution of uranium in the environment. The uranium leaching conditions from phosphate rock were estimated using alkaline solutions. The changes in the natural phosphate rock after leaching were studied. The amenability to separate the uranium from phosphate rock with ammonium carbonate / bicarbonate solution was determined. The uranium extraction was approximately 40%. The leaching conditions showed high selectivity for uranium without changes in the ore structure. The bulk ore was not dissolved. (Author)

  5. Zinc phosphating of 6061-Al alloy using REN as additive

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shenglin; ZHANG Xiaolin; ZHANG Mingming

    2008-01-01

    Zinc phosphate coating formed on 6061-Al alloy was studied with the help of electrochemical measurements, Fourier Transform Infrared (FTIR), and Scanning Electron Microscopy (SEM), after dipping it in phosphating solutions containing different concentrations of Rare Earth Nitrate (REN). REN, which acted as an accelerator in the phosphating solution, could catalyze the surface reaction and accelerate the phosphating process. REN mainly enabled the P in the phosphate coating to exist in the form of PO43- and promoted the hydrolysis of phosphatic acid in a liquid layer at the cathodes. This resulted in the evolution of H2 at the cathodes, which increased the local pH value and in turn drove the precipitation of the phosphate coating. Additionally, REN was adsorbed on the surface of the aluminum substrates to form a gel during the phosphating process. These gel particles were good crystal seeds, which helped to form phosphate crystal nuclei and possess the function of a nucleation agent that could decrease the phosphate crystal size. The corrosion resistance of the formed zinc phosphate coatings was improved.

  6. Characteristics of phosphate adsorption onto granulated coal ash in seawater.

    Science.gov (United States)

    Asaoka, Satoshi; Yamamoto, Tamiji

    2010-08-01

    The deterioration of sediments is a serious environmental problem. Controlling nutrient release fluxes from sediments is important to alleviating eutrophication and to reducing terrigenous nutrient loads. The purpose of this study was to evaluate the phosphate removal performance of granulated coal ash (GCA) from seawater, which is produced from coal thermal electric power generation. Batch experiments were carried out to investigate the removal kinetics of phosphate from seawater under both oxic and anoxic conditions. Phosphate was removed well from seawater under both oxic and anoxic conditions. The adsorption isotherm for phosphate revealed that GCA could remove phosphate effectively from seawater above a concentration of 1.7micromolL(-1). GCA can reduce the concentration of phosphate in seawater effectively under anoxic conditions where iron type adsorbents cannot be applied. Therefore, GCA could potentially be used to adsorb phosphate in the organically-enriched sediment, which generally occurs under highly reductive conditions. PMID:20403625

  7. Agronomic Effectiveness of Partially Acidulated Phosphate Rock

    Institute of Scientific and Technical Information of China (English)

    HENIAN-ZU; SUNQI-WEI

    1994-01-01

    Laboratorial incubation and field experiments were conducted on soils ranging in texture from sandy loam to clay and in pH from 3.6 to 9.0 to determine the agronomic effectiveness of single superphosphate (SSP).fused magnesium phosphate(FMP) and partially acidulated phosphate rock(PAPR) on 8 field crops.The results showed that the pattern of available P released from SSP was fixing-releasing-fixing-steady state,while that of PAPR was shortly fixing-slowly releasing-fixing steady state.And the PAPR,SSP and FMP were equally effective as judged by yield Puptake by phants and extractable P in soils after crop harvesting,The PAPR used as basal fertilizer was more effective than that as top dressing,and its residual effect was also obvious.

  8. Radiophotoluminescence from silver-doped phosphate glass

    International Nuclear Information System (INIS)

    Glass dosimeter utilizing radiophotoluminescence (RPL) is one of accumulation type solid state dosimeters, which is based on luminescence phenomenon of silver (Ag+ ions)-doped phosphate glass exposed to ionizing radiation. In this study, to clarify the emission mechanism of yellow and blue RPL peaks, optical properties of Ag+-doped glass, such as optical absorption spectrum, RPL excitation spectrum before and after X-ray irradiation as well as the lifetime of both RPL peaks are measured. From the results, we discuss the emission mechanism of yellow (peaked at 2.21 eV) and blue (peaked at 2.70 eV) RPL using a proposed energy band diagram for RPL emission and excitation in Ag+-doped phosphate glass. It is found that the radiative lifetime of blue RPL is three orders of magnitude faster than that of yellow RPL.

  9. Biomedical monitoring of phosphate removal by hemodialysis.

    Science.gov (United States)

    Michalec, Michał; Fiedoruk-Pogrebniak, Marta; Matuszkiewicz-Rowińska, Joanna; Tymecki, Łukasz; Koncki, Robert

    2016-07-15

    A compact flow analysis system for non-invasive, dialysate-side monitoring of phosphate removal in the course of clinical hemodialysis treatment is presented. The monitor is based on solenoid operated micro-pumps and extremely cheap optoelectronic flow-through detector allowing photometric determination of phosphate in spent dialysate using a molybdenum blue method. The monitor can operate in both, discrete and continuous modes of measurement. The analytical utility of monitor has been tested with samples of spent dialysate produced by artificial kidney in the course of real hemodialysis sessions. The results of monitoring are comparable with those obtained using reference off-line method recommended for clinical analysis. Additionally, the possibility of two-side (dialysate and blood) monitoring of hemodialysis treatments with optoelectronic flow-through detectors has been announced. PMID:27136282

  10. Aluminum phosphate ceramics for waste storage

    Science.gov (United States)

    Wagh, Arun; Maloney, Martin D

    2014-06-03

    The present disclosure describes solid waste forms and methods of processing waste. In one particular implementation, the invention provides a method of processing waste that may be particularly suitable for processing hazardous waste. In this method, a waste component is combined with an aluminum oxide and an acidic phosphate component in a slurry. A molar ratio of aluminum to phosphorus in the slurry is greater than one. Water in the slurry may be evaporated while mixing the slurry at a temperature of about 140-200.degree. C. The mixed slurry may be allowed to cure into a solid waste form. This solid waste form includes an anhydrous aluminum phosphate with at least a residual portion of the waste component bound therein.

  11. Calcium phosphate cements properties with polymers addition

    International Nuclear Information System (INIS)

    Calcium phosphate cements (CPC) have attracted great interest to use in orthopedics and dentistry as replacements for damaged parts of the skeletal system, showing good biocompatibility and osseointegration, allowing its use as bone graft. Several studies have shown that the addition of polymer additives have a strong influence on the cement properties. The low mechanical strength is the main obstacle to greater use of CPC as an implant material. The objective of this study was to evaluate properties of a cement based on α-tricalcium phosphate (α-TCP), added polymers. PVA (10%, 8%, 6%), sodium alginate (2%) and polyacrylate ammonia (3%), all in weight, were added to the synthesized α-TCP powder. The samples were molded and evaluated for density, porosity in vitro test (Simulated Body Fluid), crystalline phases and mechanical strength. The results show increased the mechanical properties of the cement when added these polymers

  12. Lithium Phosphate Glasses stabilized with Tungsten Oxide

    Czech Academy of Sciences Publication Activity Database

    Míka, M.; Mladonický, P.; Vondrák, Jiří; Stopka, Pavel; Klápště, Břetislav

    Brno: University of Technology Brno, 2002, s. 50-1-50-4. ISBN 80-214-2082-0. [Advanced Batteries and Accumulators /3./. Brno (CZ), 16.06.2002-20.06.2002] R&D Projects: GA AV ČR IAA4032002; GA ČR GA104/02/0731 Institutional research plan: CEZ:AV0Z4032918 Keywords : lithium phosphate * glass * tungsten oxide Subject RIV: CA - Inorganic Chemistry

  13. Structural basis for phosphatidylinositol-phosphate biosynthesis

    OpenAIRE

    Clarke, Oliver B.; Tomasek, David; Jorge, Carla D.; Dufrisne, Meagan Belcher; Kim, Minah; Banerjee, Surajit; Rajashankar, Kanagalaghatta R.; Shapiro, Lawrence; Hendrickson, Wayne A.; Santos, Helena; Mancia, Filippo

    2015-01-01

    Phosphatidylinositol is critical for intracellular signalling and anchoring of carbohydrates and proteins to outer cellular membranes. The defining step in phosphatidylinositol biosynthesis is catalysed by CDP-alcohol phosphotransferases, transmembrane enzymes that use CDP-diacylglycerol as donor substrate for this reaction, and either inositol in eukaryotes or inositol phosphate in prokaryotes as the acceptor alcohol. Here we report the structures of a related enzyme, the phosphatidylinosito...

  14. Controlling reaction specificity in pyridoxal phosphate enzymes

    OpenAIRE

    Michael D Toney

    2011-01-01

    Pyridoxal 5'-phosphate enzymes are ubiquitous in the nitrogen metabolism of all organisms. They catalyze a wide variety of reactions including racemization, transamination, decarboxylation, elimination, retro-aldol cleavage, Claisen condensation, and others on substrates containing an amino group, most commonly α-amino acids. The wide variety of reactions catalyzed by PLP enzymes is enabled by the ability of the covalent aldimine intermediate formed between substrate and PLP to stabilize carb...

  15. Roles of Sphingosine-1-Phosphate in Reproduction

    OpenAIRE

    Guo, Lei; Ou, Xianghong; Li, Hong; Han, Zhiming

    2014-01-01

    Sphingosine-1-phosphate (S1P) plays crucial roles in the regulation of cell growth, proliferation, differentiation, cell survival, migration, and angiogenesis. In the reproductive system, S1P protects mammalian germ cells from irradiation or chemotherapy-induced cell death in vivo and in vitro. Moreover, S1P could improve the survival rate of thawed ovary and transplanted ovary. Furthermore, S1P could improve the developmental potential of oocyte and preimplantation embryo. In conclusion, S1P...

  16. High density polyethylene and zirconium phosphate nanocomposites

    OpenAIRE

    Adan Santos Lino; Luis Claudio Mendes; Daniela de França da Silva; Olaf Malm

    2015-01-01

    Abstract Nanocomposite based on high density polyethylene (HDPE) and layered zirconium phosphate organically modified with octadecylamine (ZrPOct) was obtained through melt processing. The ZrPOct was synthesized by precipitation and modified by suspension and sonication procedures. The initial and maximum degradation temperatures (Tonset and Tmax) were increased. A slight decrease of crystallinity degree was detected. Reduction of elastic modulus and elongation at break were noticed. The lame...

  17. Phosphate valorization by dry chlorination route

    Directory of Open Access Journals (Sweden)

    Kanari N.

    2016-01-01

    Full Text Available This work deals with the extraction of phosphorus chlorinated compounds from phosphate materials using chlorination with gaseous chlorine. An industrial sample of dicalcium phosphate dihydrate, after transformation into calcium pyrophosphate (Ca2P2O7, is subjected to reactions with Cl2+CO+N2 and Cl2+C+N2 at temperatures ranging from 625 to 950°C using boat experiments. Gathering results of the thermodynamic predictions and TG/DT analysis with those of SEM and XRD examinations of the chlorinated residues allowed the interpretation of phenomena and reactions mechanism occurring during the calcium pyrophosphate carbochlorination. Reaction rate of Ca2P2O7 by Cl2+CO+N2 at 950°C is slowed down due to the formation of a CaCl2 liquid layer acting as a barrier for the diffusion of the reactive gases and further reaction progress. While, the carbochlorination with Cl2+C+N2 led to almost full chlorination of Ca2P2O7 at 750°C and the process proceeds with an apparent activation energy of about 104 kJ/mol between 625 and 750°C. Carbochlorination technique can be considered as an alternative and selective route for the valorization of low grade phosphates and for the phosphorus extraction from its bearing materials.

  18. Nano-porous calcium phosphate balls.

    Science.gov (United States)

    Kovach, Ildyko; Kosmella, Sabine; Prietzel, Claudia; Bagdahn, Christian; Koetz, Joachim

    2015-08-01

    By dropping a NaH2PO4·H2O precursor solution to a CaCl2 solution at 90°C under continuous stirring in presence of two biopolymers, i.e. gelatin (G) and chitosan (C), supramolecular calcium phosphate (CP) card house structures are formed. Light microscopic investigations in combination with scanning electron microscopy show that the GC-based flower-like structure is constructed from very thin CP platelets. Titration experiments indicate that H-bonding between both biopolymers is responsible for the synergistic effect in presence of both polymers. Gelatin-chitosan-water complexes play an important role with regard to supramolecular ordering. FTIR spectra in combination with powder X-ray diffraction show that after burning off all organic components (heating up >600°C) dicalcium and tricalcium phosphate crystallites are formed. From high resolution transmission electron microscopy (HR-TEM) it is obvious to conclude, that individual crystal platelets are dicalcium phosphates, which build up ball-like supramolecular structures. The results reveal that the GC guided crystal growth leads to nano-porous supramolecular structures, potentially attractive candidates for bone repair. PMID:26052107

  19. Fabrication and properties of terbium phosphate nanorods

    International Nuclear Information System (INIS)

    Recently, luminescent nanomaterials with one-dimensional (1D) structured form have been extensively investigated as fluorescent label agents in biology. Among them, 1D nanostructured terbium compounds (for example terbium phosphate) have attracted great attention due to their high-emission efficiency in water. In this report, terbium phosphate nanorods were successfully prepared by hydrothermal method in autoclave for the first time. This method is a simple one, which permits obtaining large-scale, uniform and pure product. The size of the rods can be controlled precisely. The nanorods have diameters from 15 to 50 nm, and lengths from 300 to 500 nm. Based on the effects of change of pH values to the size, crystalline structure and morphology of terbium phosphate nanorods, field emission scanning electron microscopy (FE-SEM) and x-ray diffraction (XRD) data of the as-synthesized samples have been elucidated. The photoluminescent (PL) spectra of TbPO4 nanorods have been measured at room temperature under ultraviolet excitation and show four high luminescence main peaks at 490, 545, 585 and 620 nm

  20. Phosphate phosphors for solid-state lighting

    Energy Technology Data Exchange (ETDEWEB)

    Shinde, Kartik N. [N.S. Science and Arts College, Bhadrawati (India). Dept. of Physics; Swart, H.C. [University of the Orange Free State, Bloemfontein (South Africa). Dept. of Physics; Dhoble, S.J. [R.T.M. Nagpur Univ. (India). Dept. of Physics; Park, Kyeongsoon [Sejong Univ., Seoul (Korea, Republic of). Faculty of Nanotechnology and Advanced Materials Engineering

    2012-07-01

    Essential information for students in researchers working towards new and more efficient solid-state lighting. Comprehensive survey based on the authors' long experience. Useful both for teaching and reference. The idea for this book arose out of the realization that, although excellent surveys and a phosphor handbook are available, there is no single source covering the area of phosphate based phosphors especially for lamp industry. Moreover, as this field gets only limited attention in most general books on luminescence, there is a clear need for a book in which attention is specifically directed toward this rapidly growing field of solid state lighting and its many applications. This book is aimed at providing a sound introduction to the synthesis and optical characterization of phosphate phosphor for undergraduate and graduate students as well as teachers and researchers. The book provides guidance through the multidisciplinary field of solid state lighting specially phosphate phosphors for beginners, scientists and engineers from universities, research organizations, and especially industry. In order to make it useful for a wide audience, both fundamentals and applications are discussed, together.

  1. Phosphate adsorption on lanthanum loaded biochar.

    Science.gov (United States)

    Wang, Zhanghong; Shen, Dekui; Shen, Fei; Li, Tianyu

    2016-05-01

    To attain a low-cost and high-efficient phosphate adsorbent, lanthanum (La) loaded biochar (La-BC) prepared by a chemical precipitation method was developed. La-BC and its pristine biochar (CK-BC) were comparatively characterized using zeta potential, BET surface area, scanning electron microscopy/energy dispersive spectrometer (SEM-EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR). The adsorption ability and the mechanisms during adsorption process for the La-BC samples were also investigated. La loaded on the surface of biochar can be termed as La-composites (such as LaOOH, LaONO3 and La(OH)3), leading to the decrease of negative charge and surface area of biochar. La-BC exhibited the high adsorption capacity to phosphate compared to CK-BC. Adsorption isotherm and adsorption kinetic studies showed that the Langmuir isotherm and second order model could well describe the adsorption process of La-BC, indicating that the adsorption was dominated by a homogeneous and chemical process. The calculated maximum adsorption capacity was as high as 46.37 mg g(-1) (computed in P). Thermodynamic analysis revealed that the adsorption was spontaneous and endothermic. SEM, XRD, XPS and FT-IR analysis suggested that the multi-adsorption mechanisms including precipitation, ligand exchange and complexation interactions can be evidenced during the phosphate adsorption process by La-composites in La-BC. PMID:26871732

  2. Fabrications of zinc-releasing biocement combining zinc calcium phosphate to calcium phosphate cement.

    Science.gov (United States)

    Horiuchi, Shinya; Hiasa, Masahiro; Yasue, Akihiro; Sekine, Kazumitsu; Hamada, Kenichi; Asaoka, Kenzo; Tanaka, Eiji

    2014-01-01

    Recently, zinc-releasing bioceramics have been the focus of much attention owing to their bone-forming ability. Thus, some types of zinc-containing calcium phosphate (e.g., zinc-doped tricalcium phosphate and zinc-substituted hydroxyapatite) are examined and their osteoblastic cell responses determined. In this investigation, we studied the effects of zinc calcium phosphate (ZCP) derived from zinc phosphate incorporated into calcium phosphate cement (CPC) in terms of its setting reaction and MC3T3-E1 osteoblast-like cell responses. Compositional analysis by powder X-ray diffraction analysis revealed that HAP crystals were precipitated in the CPC containing 10 or 30wt% ZCP after successfully hardening. However, the crystal growth observed by scanning electron microscopy was delayed in the presence of additional ZCP. These findings indicate that the additional zinc inhibits crystal growth and the conversion of CPC to the HAP crystals. The proliferation of the cells and alkaline phosphatase (ALP) activity were enhanced when 10wt% ZCP was added to CPC. Taken together, ZCP added CPC at an appropriate fraction has a potent promotional effect on bone substitute biomaterials. PMID:24090874

  3. The effect of rock phosphates on the content of mineral phosphate forms in Sod-podzolic soils

    International Nuclear Information System (INIS)

    The dynamics of content and changes in the mineral forms of phosphates as a result from the application of rock phosphates (RP) from the Polpino deposit to a Sod-podzolic soil was studied. Thirty days after phosphate rock application to soil, up to 59.2% of all phosphates were in the form of sparingly soluble Ca phosphates. After 200 days, only 36.5% of local RP remained in the original form. The process of P conversion from RP was accompanied by the formation of Ca, Mg, Fe, and Al phosphates. The extent, to which phosphate was mobile, was determined by RP dissolution rates and time of contact with soil. Significant differences in the available soil P values determined by chemical, radiochemical and greenhouse methods were found. (author)

  4. Proton transport properties of tin phosphate, chromotropic acid anchored onto tin phosphate and tin phenyl phosphonate

    Indian Academy of Sciences (India)

    Chithra Sumej; P P Sharmila; Nisha J Tharayil; S Suma

    2013-02-01

    Tin (IV) phosphates of the class of tetravalent metal acid (TMA) salts have been synthesized by sol–gel method. The functionalized materials of tin (IV) phosphate (SnP) like chromotropic acid anchored tin phosphate (SnPCA) and tin phenyl phosphonate (SnPP) were also synthesized. These materials have been characterized for elemental analysis (ICP–AES), thermal analysis, X-ray analysis and FTIR spectroscopy. Chemical resistivity of these materials has been accessed in acidic, basic and organic solvent media. The proton present in the structural hydroxyl groups indicates good potential for TMA salts to exhibit solid-state proton conduction. The transport properties of these materials have been explored by measuring specific proton conductance at different temperatures. Based on the specific conduction data and Arrhenius plots, a suitable mechanism has been proposed.

  5. A safer disposal of hazardous phosphate coating sludge by formation of an amorphous calcium phosphate matrix.

    Science.gov (United States)

    Navarro-Blasco, I; Duran, A; Pérez-Nicolás, M; Fernández, J M; Sirera, R; Alvarez, J I

    2015-08-15

    Phosphate coating hazardous wastes originated from the automotive industry were efficiently encapsulated by an acid-base reaction between phosphates present in the sludge and calcium aluminate cement, yielding very inert and stable monolithic blocks of amorphous calcium phosphate (ACP). Two different compositions of industrial sludge were characterized and loaded in ratios ranging from 10 to 50 wt.%. Setting times and compressive strengths were recorded to establish the feasibility of this method to achieve a good handling and a safe landfilling of these samples. Short solidification periods were found and leaching tests showed an excellent retention for toxic metals (Zn, Ni, Cu, Cr and Mn) and for organic matter. Retentions over 99.9% for Zn and Mn were observed even for loadings as high as 50 wt.% of the wastes. The formation of ACP phase of low porosity and high stability accounted for the effective immobilization of the hazardous components of the wastes. PMID:26024992

  6. Research and engineering assessment of biological solubilization of phosphate

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, R.D.; McIlwain, M.E.; Losinski, S.J.; Taylor, D.D.

    1993-03-01

    This research and engineering assessment examined a microbial phosphate solubilization process as a method of recovering phosphate from phosphorus containing ore compared to the existing wet acid and electric arc methods. A total of 860 microbial isolates, collected from a range of natural environments were tested for their ability to solubilize phosphate from rock phosphate. A bacterium (Pseudomonas cepacia) was selected for extensive characterization and evaluation of the mechanism of phosphate solubilization and of process engineering parameters necessary to recover phosphate from rock phosphate. These studies found that concentration of hydrogen ion and production of organic acids arising from oxidation of the carbon source facilitated microbial solubilization of both pure chemical insoluble phosphate compounds and phosphate rock. Genetic studies found that phosphate solubilization was linked to an enzyme system (glucose dehydrogenase). Process-related studies found that a critical solids density of 1% by weight (ore to liquid) was necessary for optimal solubilization. An engineering analysis evaluated the cost and energy requirements for a 2 million ton per year sized plant, whose size was selected to be comparable to existing wet acid plants.

  7. Identification and functional reconstitution of phosphate: sugar phosphate antiport of Staphylococcus aureus

    International Nuclear Information System (INIS)

    Resting cells of Staphylococcus aureus displayed a phosphate (Pi) exchange that was induced by growth with glucose 6-phosphate (G6P) or sn-glycerol 3-phosphate (G3P). Pi-loaded membrane vesicles from these cells accumulated 32Pi, 2-deoxyglucose 6-phosphate (2DG6P) or G3P by an electroneutral exchange that required no external source of energy. On the other hand, when vesicles were loaded with morpholinopropane sulfonic acid (MOPS), only transport of 32Pi (and L-histidine) was observed, and in that case transport depended on addition of an oxidizable substrate (DL-lactate). In such MOPS-loaded vesicles, accumulation of the organic phosphates, 2DG6P and G3P, could not be observed until vesicles were preincubated with both Pi and DL-lactate to establish an internal pool of Pi. This trans effect demonstrates that movement of 2DG6P or G3P is based on an antiport (exchange) with internal Pi. Reconstitution of membrane protein allowed a quantitative analysis of Pi-linked exchange. Pi-loaded proteoliposomes and membrane vesicles had comparable activities for the homologous 32Pi: Pi exchange (Kt's of 2.2 and 1.4 mM; Vmax's of 180 and 83 nmol Pi/min per mg protein), indicating that the exchange reaction was recovered intact in the artificial system. Other work showed that heterologous exchange from either G6P- or G3P-grown cells had a preference for 2DG6P (Kt = 27 microM) over G3P (Kt = 1.3 mM) and Pi (Kt = 2.2 mM), suggesting that the same antiporter was induced in both cases. We conclude that 32Pi: Pi exchange exhibited by resting cells reflects operation of an antiporter with high specificity for sugar 6-phosphate

  8. Effectiveness of a rock phosphate solubilizing fungus to increase soil solution phosphate impaired by the soil phosphate sorption capacity

    Directory of Open Access Journals (Sweden)

    Nelson Walter Osorio Vega

    2015-06-01

    Full Text Available Available phosphate (P deficiency in tropical soils has been recognized as a major factor that limits soil quality and plant performance. To overcome this, it is necessary to add high amounts of soluble P-fertilizers; however, this is inefficient and costly. Alternatively, rock phosphates (RP can be used, but their low reactivity limits their use. Phosphate solubilizing microorganisms (PSM can enhance RP dissolution and, thus, improve the RP agronomic effectiveness as fertilizer. Nonetheless, their effectiveness may be impaired by the soil P fixation capacity. An experiment was carried out to assess the in vitro effectiveness of the fungus Mortierella sp. to dissolve RP in an axenic culture medium and, thus, enhance the solution P concentration in the presence of aliquots of soils with contrasting P fixation capacity. The results showed that the fungus was capable of lowering the medium pH from 7.7 to 3.0 and, thus, dissolving the RP. The presence of soil aliquots in the medium controlled the effectiveness of the fungus to increase the concentration of the soluble P. In the presence of soils with a low or medium P sorption capacity, the concentration of the soluble P was high (63.8-146.6 mg L-1 in comparison with the inoculated (soilless treatment (50.0 mg L-1 and the uninoculated control (0.7 mg L-1. By contrast, with very-high P fixing soil aliquots, the concentration of the soluble P was very low (3.6-33.1 mg L-1; in addition, in these soils, the fungus immobilized more P into its mycelia than in soils with a low or medium P fixation capacity. The capacity of a soil to fix P seems to be a good predictor for the effectiveness of this fungus to increase the soluble P concentration via RP dissolution.

  9. Meal phosphate variability does not support fixed dose phosphate binder schedules for patients treated with peritoneal dialysis: a prospective cohort study

    OpenAIRE

    Leung, Simon; McCormick, Brendan; Wagner, Jessica; Biyani, Mohan; Lavoie, Susan; Imtiaz, Rameez; Zimmerman, Deborah

    2015-01-01

    Background Removal of phosphate by peritoneal dialysis is insufficient to maintain normal serum phosphate levels such that most patients must take phosphate binders with their meals. However, phosphate ‘counting’ is complicated and many patients are simply prescribed a specific dose of phosphate binders with each meal. Therefore, our primary objective was to assess the variability in meal phosphate content to determine the appropriateness of this approach. Methods In this prospective cohort s...

  10. X-ray study of double phosphates of sodium-zirconium-phosphate family

    International Nuclear Information System (INIS)

    MnM24(PO4)3 titanium, zirconium and hafnium phosphates where M-Li, Na, K, Rb, Cs (n=1) and M-Mg, Ca, Sr, Ba (n=0.5), are prepared. Crystallographic features are generalized. Regular variations of unit cell parameters in series of synthesized phases crystallizing within R3c-D3d6 symmetry group trigonal crystal system are shown. Isostructure of M1M24(PO4)3 and M0.52M24(PO4)3 series phosphates is determined

  11. The aluminum phosphate zone in the Peace River area, land-pebble phosphate field, Florida

    Science.gov (United States)

    Cathcart, James B.

    1953-01-01

    The Peace River area, comprising T. 30 and 31 S., R. 24 and 25 E., contains a thicker and more persistent aluminum phosphate zone, and one that is higher in P2O5 and uranium content than is known elsewhere in the land-pebble phosphate district. This report has been prepared to bring together all of the information on the aluminum phosphate zone in the area where the first plant to treat this material will probably be located. The area may be divided into three physiographic units, (1) the ridge, (2) the flatwoods, and (3) the valley. Maps showing distribution and grade of the aluminum phosphate zone indicate that the zone is thin or absent in the ridge unit, thickest and most persistent, and of the best grade in P2O5 and uranium in the flatwoods unit, and absent or very low in grade in the valley unit. Maps of thickness and of chemical composition show that even in favorable areas there are places where the aluminum phosphate zone is missing or of questionable economic importance. The distribution maps also show that areas of high P2O5 and high uranium content coincide closely. Areas containing thick aluminum phosphate material usually have high uranium and P2O5 contents. It is estimated that an average of 13,000 tons per day of aluminum phosphate material might be mined from this area. This figure is based on the probable amount of time, per year, that mining would be in favorable ground. When all mines in the area are in favorable ground, the tonnage per day might be about 23,000 tons. Tonnages of aluminum phosphate material have been computed for about 36 percent of the area of T. 30 S., R. 25 E., and for 18 percent of the area of T. 31 S., R. 25 E. The total inferred tonnage is about 150,000,000 short tons, with an average grade of 0.012 percent U3O8.

  12. Integrated assessment of the phosphate industry. [Radiological impact of uranium extraction

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, M.T.; Cotter, S.J.

    1980-05-01

    The phosphate industry in the United States includes three major activities, namely, mining and milling of phosphate rock, phosphate product manufacture, and phosphate product use. Phosphatic materials contain uranium, thorium, and their decay products in greater than background amounts. This assessment of the radiological impacts associated with the redistribution of radioactive components of phosphate materials may provide insight into the effects of uranium extraction from phosphate materials for use in the nuclear fuel cycle.

  13. Plant tissue hybrid electrode for determination of phosphate and fluoride

    Energy Technology Data Exchange (ETDEWEB)

    Schubert, F.; Renneberg, R.; Scheller, F.W.; Kirstein, L.

    1984-08-01

    A biosensor for inorganic phosphate and fluoride has been developed by coupling a potato (Solanum tuberosum) tissue slice and immobilized glucose oxidase with a Clark oxygen electrode. Measurement is based on the inhibition by either ion of potato acid phosphates catalyzed glucose 6-phosphate hydrolysis. The precision is 1.7% and 6.5% and the lower detection limit 2.5 X 10/sup -5/ M and 1 X 10/sup -4/ M for phosphate and fluoride, respectively. For phosphate determination the hybrid sensor is stable for 28 days or 300 assays. With a higher limit of detection the sensor can be applied in a commercial enzyme electrode based device. Its application for phosphate determination in fertilizer and urine samples is described.

  14. Carbon Mineralization Using Phosphate and Silicate Ions

    Science.gov (United States)

    Gokturk, H.

    2013-12-01

    Carbon dioxide (CO2) reduction from combustion of fossil fuels has become an urgent concern for the society due to marked increase in weather related natural disasters and other negative consequences of global warming. CO2 is a highly stable molecule which does not readily interact with other neutral molecules. However it is more responsive to ions due to charge versus quadrupole interaction [1-2]. Ions can be created by dissolving a salt in water and then aerosolizing the solution. This approach gives CO2 molecules a chance to interact with the hydrated salt ions over the large surface area of the aerosol. Ion containing aerosols exist in nature, an example being sea spray particles generated by breaking waves. Such particles contain singly and doubly charged salt ions including Na+, Cl-, Mg++ and SO4--. Depending on the proximity of CO2 to the ion, interaction energy can be significantly higher than the thermal energy of the aerosol. For example, an interaction energy of 0.6 eV is obtained with the sulfate (SO4--) ion when CO2 is the nearest neighbor [2]. In this research interaction between CO2 and ions which carry higher charges are investigated. The molecules selected for the study are triply charged phosphate (PO4---) ions and quadruply charged silicate (SiO4----) ions. Examples of salts which contain such molecules are potassium phosphate (K3PO4) and sodium orthosilicate (Na4SiO4). The research has been carried out with first principle quantum mechanical calculations using the Density Functional Theory method with B3LYP functional and Pople type basis sets augmented with polarization and diffuse functions. Atomic models consist of the selected ions surrounded by water and CO2 molecules. Similar to the results obtained with singly and doubly charged ions [1-2], phosphate and silicate ions attract CO2 molecules. Energy of interaction between the ion and CO2 is 1.6 eV for the phosphate ion and 3.3 eV for the silicate ion. Hence one can expect that the selected

  15. Preparation and Characterization of Porous Calcium Phosphate Bioceramics

    Institute of Scientific and Technical Information of China (English)

    Honglian Dai; Xinyu Wang; Yinchao Han; Xin Jiang; Shipu Li

    2011-01-01

    β-tricalcium phosphate (β-TCP) powder and Na2O-CaO-MgO-P2O5 glass binder were synthesized and mixed, and then the biodegradable porous calcium phosphate ceramics were successfully prepared by foaming and sintering at 850℃. The as-prepared ceramics possess a high porosity with partial three-dimension interconnected macro- and micro-pores. As in vitro experiment testified, the calcium phosphate ceramics (CPCs) has good degradability.

  16. Effect of phosphate on lipid metabolism in Fusarium oxysporum

    OpenAIRE

    J. S. Arneja

    2014-01-01

    The effect of different phosphate levels in the growth medium on lipid metabolism in Fusarium oxysporum, was studied. An increase in the phosphate level led on to an increase in the phosphorus content of the mycelium, as well as in that of total lipids. However, higher phosphate concentrations, had no profound effect on the total lipid percentage. Among phospholipid compounds phosphatidic acid (PA) and phosphatidyl inositol were the most susceptible while phisphatidyl choline (PC) was found t...

  17. Investigation of Structural Mimetics of Natural Phosphate Ion Binding Motifs

    OpenAIRE

    Evgeny A. Kataev; Tatiana A. Shumilova

    2015-01-01

    Phosphates are ubiquitous in biology and nearly half of all proteins interact with their partners by means of recognition of phosphate residues. Therefore, a better understanding of the phosphate ion binding by peptidic structures is highly desirable. Two new receptors have been designed and synthesized and their anion binding properties in an acetonitrile solution have been determined. The structure of hosts mimics a part of the kinase active site that is responsible for the recognition of ...

  18. Plant growth promotion induced by phosphate solubilizing endophytic Pseudomonas isolates

    OpenAIRE

    Oteino, Nicholas; Lally, Richard D.; Kiwanuka, Samuel; Lloyd, Andrew; Ryan, David; Germaine, Kieran J.; Dowling, David N.

    2015-01-01

    The use of plant growth promoting bacterial inoculants as live microbial biofertilizers provides a promising alternative to chemical fertilizers and pesticides. Inorganic phosphate solubilization is one of the major mechanisms of plant growth promotion by plant associated bacteria. This involves bacteria releasing organic acids into the soil which solubilize the phosphate complexes converting them into ortho-phosphate which is available for plant up-take and utilization. The study presented h...

  19. Investigation of Wear Coefficient of Manganese Phosphate Coated Tool Steel

    OpenAIRE

    S. Ilaiyavel; Venkatesan, A.

    2013-01-01

    In recent years the properties of the coating in terms of wear resistance is of paramount importance in order to prevent the formation of severe damages. In this study, Wear coefficient of uncoated, Manganese Phosphate coated, Manganese Phosphate coated with oil lubricant, Heat treated Manganese Phosphate coated with oil lubricant on AISI D2 steels was investigated using Archard’s equation. The wear tests were performed in a pin on disk apparatus as per ASTM G-99 Standard. The volumetric wear...

  20. Truth and consequences of sphingosine-1-phosphate lyase

    OpenAIRE

    Aguilar, Ana; Saba, Julie D.

    2011-01-01

    Sphingosine phosphate lyase (SPL) is an intracellular enzyme responsible for the irreversible catabolism of the lipid signaling molecule sphingosine-1-phosphate (S1P). SPL catalyzes the cleavage of S1P resulting in the formation of hexadecenal and ethanolamine phosphate. S1P functions as a ligand for a family of ubiquitously expressed G protein-coupled receptors that mediate autocrine and paracrine signals controlling cell migration, proliferation and programmed cell death pathways. S1P has a...

  1. Na-Gd phosphate glasses for scintillators

    Czech Academy of Sciences Publication Activity Database

    Nitsch, Karel; Cihlář, Antonín; Rodová, Miroslava

    Bratislava: x, 2005 - (Koman, M.; Mikloš, D.), s. 56 ISBN 80-89088-42-2. [Development of Materials Science in Research and Education - DMS -RE 2005 /15./. Kežmarské Žĺaby (SK), 05.09.2005-09.09.2005] R&D Projects: GA AV ČR IAA2010304 Institutional research plan: CEZ:AV0Z10100521 Keywords : Ce-doped Na-Gd phosphate glasses * radioluminescence * thermal properties Subject RIV: BM - Solid Matter Physics ; Magnetism

  2. Biogenesis of the mitochondrial phosphate carrier

    OpenAIRE

    Zara, Vincenzo; Rassow, Joachim; Wachter, Elmar; Tropschug, Maximilian; Palmieri, Ferdinando; Neupert, Walter; Pfanner, Nikolaus

    1991-01-01

    The mitochondrial phosphate carrier (PiC) is a member of the family of inner-membrane carrier proteins which are generally synthesized without a cleavable presequence. Surprisingly, the cDNA sequences of bovine and rat PiC suggested the existence of an amino-terminal extension sequence in the precursor of PiC. By expressing PiC in vitro, we found that PiC is indeed synthesized as a larger precursor. This precursor was imported and proteolytically processed by mitochondria, whereby the correct...

  3. Characterisation of Erbium Doped Phosphate Glass

    International Nuclear Information System (INIS)

    A series of erbium doped phosphate glass has been successfully fabricated, and the determination of their density and luminescence properties has been carried out. It is particularly interesting to study the effect of modifying oxides to the properties of the glass. The glass density reduces with the increasing content of Na2O. The emission spectra from luminescence spectroscopy resolved six emission peaks from the excitation wavelength of 336.8 nm (3.69 eV). The emission of 4F7/2 gives two emission peaks, where the peak near 482 nm shows a higher intensity and the peak near 491 nm gives a weak emission spectra.

  4. Crystal structure of L-alanine phosphate

    International Nuclear Information System (INIS)

    The crystal structure of L-alanine phosphate (C3O2NH7 · H3PO4) is determined by the single-crystal diffraction technique; a 11.918(1) A, b = 9.117(1) A, c = 7.285(1) A, γ = 104.7(1) deg., space group P21, and Z = 4. The amino group of the alanine is protonated by the hydrogen atom of the phosphoric acid. Pairs of H2PO-4 hydrogen-bonded ions are packed into layers alternating with layers of alanine molecules in the crystal. No hydrogen bonds are formed immediately between the alanine molecules

  5. Interactions between organic amendments and phosphate fertilizers modify phosphate sorption processes in an acid soil

    Energy Technology Data Exchange (ETDEWEB)

    Sckefe, C.R.; Patti, A.F.; Clune, T.S.; Jackson, W.R. [Rutherglen Center, Rutherglen, Vic. (Australia)

    2008-07-15

    To determine how organic amendments and phosphate fertilizers interact to modify P sorption processes, three phosphate fertilizers were applied to lignite- and compost-amended acid soil and incubated for either 3 or 26 days. The fertilizers applied were potassium dihydrogen phosphate, triple superphosphate, and diammonium phosphate (DAP). After 3 days of incubation, sorption of all three P sources was decreased in the lignite-amended treatments, whereas P sorption was increased in the compost-amended treatments. Increased incubation time (26 days) resulted in significantly decreased P sorption when DAP was added to lignite-amended treatments. Addition of triple superphosphate increased P sorption in lignite- and compost-amended treatments and decreased solution pH compared with DAP application. In addition to the effect of P source, differences in P sorption between the lignite- and compost-amended treatments were driven by differences in solution chemistry, predominantly solution pH and cation dynamics. Soil amendment and fertilizer addition also increased microbial activity in the incubation systems, as measured by carbon dioxide respiration. It is proposed that the combination of lignite and DAP may contribute to decreased P sorption in acid soils, with the positive effects likely caused by both chemical and biological processes, including the formation of soluble organic-metal complexes.

  6. The potential of phosphate solubilizing bacteria isolated from sugarcane wastes for solubilizing phosphate

    Directory of Open Access Journals (Sweden)

    Atekan

    2014-07-01

    Full Text Available Most of P in agricultural soils is in unavailable forms for plant growth. Phosphate solubilizing bacteria can increase soil P availability. This study was aimed to isolate phosphate solubilizing bacteria from sugarcane waste compost and to test ability of the isolated bacterial to dissolve phosphate. The bacteria were isolated from three types of sugarcane waste, i.e. filter cake compost, bagasse compost, and a mixture of filter cake + bagasse + trash biomass compost. The potential colony was further purified by the Pikovskaya method on selective media. Eight isolates of phosphate solubilizing bacteria were obtained from all wasted studied. Amongst them, T-K5 and T-K6 isolates were superior in dissolving P from Ca3(PO42 in the media studied. The two isolates were able to solubilize P with solubilizing index of 1.75 and 1.67 for T-K5 and T-K6, respectively. Quantitatively, T-K6 isolate showed the highest P solubilization (0.74 mg / L, followed by T-K5 isolate (0.56 mg / L, while the lowest P solubilization (0.41 mg / L was observed for T-K4 isolate. The increase of soluble P was not always followed by the decrease in pH.

  7. Phosphate acquisition efficiency and phosphate starvation tolerance locus (PSTOL1) in rice

    Indian Academy of Sciences (India)

    Arijit Mukherjee; Sutanu Sarkar; Amrita Sankar Chakraborty; Roshan Yelne; Vinay Kavishetty; Tirthankar Biswas; N. Mandal; Somnath Bhattacharyya

    2014-12-01

    Phosphate availability is a major factor limiting tillering, grain filling vis-à-vis productivity of rice. Rice is often cultivated in soil like red and lateritic or acid, with low soluble phosphate content. To identify the best genotype suitable for these types of soils, P acquisition efficiency was estimated from 108 genotypes. Gobindabhog, Tulaipanji, Radhunipagal and Raghusail accumulated almost equal amounts of phosphate even when they were grown on P-sufficient soil. Here, we have reported the presence as well as the expression of a previously characterized rice gene, phosphate starvation tolerance locus (PSTOL1) in a set of selected genotypes. Two of four genotypes did not show any detectable expression but carried the gene. One mega cultivar, Swarna did not possess this gene but showed high P-deficiency tolerance ability. Increase of root biomass, not length, in P-limiting situations might be considered as one of the selecting criteria at the seedling stage. Neither the presence of PSTOL1 gene nor its closely-linked SSR RM1261, showed any association with P-deficiency tolerance among the 108 genotypes. Not only this, but the presence of PSTOL1 in recombinant inbred line (RIL) developed from a cross between Gobindabhog and Satabdi, also did not show any linkage with P-deficiency tolerance ability. Thus, before considering PSTOL1 gene in MAB, its expression and role in P-deficiency tolerance in the donor parent must be ascertained.

  8. REMOVAL OF PHOSPHATES FROM WATER BY PILLARED RECTORITE

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The presence of trace phosphates in treated wastewater from municipalities and industries is often responsible for eutrophication problems in lakes, rivers, and other water bodies. In this paper,we report the removal of PO43- from water by using a pillared rectorite that we synthesized recently. The results show that cross-linking can significantly increase the adsorbing capacity of Na-rectorite for phosphates. The pH, the concentrations of F, NH4+ and COD are main factors, which affect the results for pillared rectorite to adsorb phosphates from water. The OH-, and F- ions decrease the capacity to adsorb phosphates, while the COD and NH4+ ions increase it.

  9. Biomineralization of iron phosphate nanoparticles in yeast cells

    International Nuclear Information System (INIS)

    Amorphous iron phosphate nanoparticles mineralized in yeast cells are studied by transmission electron microscopy, Fourier transform infrared spectrograph and micro electrophoresis. Iron phosphate nanoparticles in yeast cells show uniform morphology with extensive surface roughness and disperse well. The size distribution of iron phosphate is about 50-200 nm. Fourier transform infrared spectroscopy (FT-IR) is used to analyze the chemical bond linkages between iron phosphate nanoparticles with protein macromolecules in yeast cells. The mechanism of biomineralization was simply discussed by chemical bonds and surface charges.

  10. Pathogenic Mineralization of Calcium Phosphate on Human Heart Valves

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    When calcium phosphate forms in soft tissues such as blood vessels and heart valves, it causes disease. The abnormal formation of calcium phosphate is called pathogenic mineralization or pathogenic calcification. Cases of rheumatic heart disease (RHD) always occur with fibrotic and calcified tissue of heart valve. In this article, samples taken from calcified human heart valves were studied. The characterization was performed by scanning electronic micrascope, X-ray Diffraction and transmission electron microscopy with selective diffraction patterns. It is found for the first time that calcium phosphate grains existing in the calcified human heart valves contain octacalcium phosphate (OCP).

  11. Naturally occurring radionuclides in soil around phosphate fertilizer industry

    International Nuclear Information System (INIS)

    Fertilizers containing phosphate have been used worldwide in increasing quantities in order to replenish natural nutrients, which are being continuously taken off from the soil due to farming activities. Phosphate rocks together with potassium ores and nitrogenous compounds are the main raw materials used for fertilizer industrial production. Rock phosphate ore processing and disposal of phosphogypsum contribute to enhance levels of natural radionuclides in the environment. The objective of this study is to estimate the concentration of naturally occurring radionuclides such as 210Po, 238U, 232Th, 226Ra and 40K in soil samples collected around a phosphate fertilizer plant. (author)

  12. Crystal structure of the phosphate-binding protein (PBP-1) of an ABC-type phosphate transporter from Clostridium perfringens

    OpenAIRE

    Gonzalez, Daniel; Richez, Magali; Bergonzi, Celine; Chabriere, Eric; Elias, Mikael

    2014-01-01

    Phosphate limitation is an important environmental stress that affects the metabolism of various organisms and, in particular, can trigger the virulence of numerous bacterial pathogens. Clostridium perfringens, a human pathogen, is one of the most common causes of enteritis necroticans, gas gangrene and food poisoning. Here, we focused on the high affinity phosphate-binding protein (PBP-1) of an ABC-type transporter, responsible for cellular phosphate uptake. We report the crystal structure (...

  13. Characterization of phosphate solubilizing bacteria isolated from Pb contaminated soils and their potential for dissolving tricalcium phosphate

    OpenAIRE

    L.E. Susilowati; Syekhfani

    2014-01-01

    Phosphorus solubilizing bacteria (PSB) enhances P availability in soils through dissolving inorganic P pools. The characteristics of PSB and the potential of three Pb tolerant phosphate solubilizing rhizobacteria, i.e. Pseudomonassp, Bacillus sp., and Actinomycites sp. were evaluated. PSB were isolated from soil samples contaminated with 300 and 500 mg Pb/kg after incubation for 30 days. Phosphate solubilizing bacteria were screened on for phosphate solubilisation ability in Pikovskaya agar m...

  14. Leishmanial phosphatase hydrolyzes phosphoproteins and inositol phosphates

    International Nuclear Information System (INIS)

    An extensively purified preparation of the predominant, tartrate-resistant acid phosphatase (ACP) from the external surface of Leishmania donovani promastigotes form catalyzes the dephosphorylation of several phosphoproteins; these include: pyruvate kinase, phosphorylase kinase and histones. However, the protein phosphatase activity of ACP is very low compared with that of other protein phosphates known to be involved in regulating various metabolic pathways. 32P-labelled inositoltriphosphate (IP3), a well-established second messenger derived from phosphatidylinositol-4,5-diphosphate (PIP2), was a substrate for the leishmanial acid phosphatase; incubation of the IP3 preparation with 13.2 milliunits (1 unit equals 1 μmol 4-methylumbelliferyl phosphate (MUP) cleaved per min at pH 5.5) of ACP at pH 5.5 for 4 hr resulted in hydrolysis of 75% of the radiolabelled substrate resulting in a mixture of inositoldiphosphate and inositolmonophosphate. In addition PIP2 was hydrolyzed rapidly by ACP at pH 5.5 (V/sub max/, 71 units/mg protein; k/sub m/, 4.16 μM). In contrast, to MUP which is hydrolzyed most rapidly at pH 5.5, PIP2 hydrolysis was optimal at pH 6.8. These observations raise the possibility that ACP could play a role in the host-phagocyte interaction by degrading the precursor of the second messenger, PIP2 or the second messenger itself, IP3

  15. Elemental analysis of Egyptian phosphate fertilizer components.

    Science.gov (United States)

    El-Bahi, S M; El-Dine, N Walley; El-Shershaby, A; Sroor, A

    2004-03-01

    The accumulation of certain elements in vitally important media such as water, soil, and food is undesirable from the medical point of view. It is clear that the fertilizers vary widely in their heavy metals and uranium content. A shielded high purity germanium HPGe detector has been used to measure the natural concentration of 238U, 232Th, and 40K activities in the phosphate fertilizer and its components collected from Abu-Zaabal fertilizers and chemical industries in Egypt. The concentration ranges were 134.97-681.11 Bq kg(-1), 125.23-239.26 Bq kg(-1), and 446.11-882.45 Bq kg(-1) for 238U, 232Th, and 40K, respectively. The absorbed dose rate and external hazard index were found to be from 177.14 to 445.90 nGy h(-1) and 1.03 to 2.71 nGy y(-1), respectively. The concentrations of 22 elements (Be, Na, Mg, Si, P, S, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Zr, Mo, Cd, Ba) in the samples under investigation were determined by inductively coupled plasma optical-emission spectrometry (ICP-OES). The results for the input raw materials (rock phosphate, limestone and sulfur) and the output product as final fertilizer are presented and discussed. PMID:14982231

  16. Erythritol feeds the pentose phosphate pathway via three new isomerases leading to D-erythrose-4-phosphate in Brucella.

    Science.gov (United States)

    Barbier, Thibault; Collard, François; Zúñiga-Ripa, Amaia; Moriyón, Ignacio; Godard, Thibault; Becker, Judith; Wittmann, Christoph; Van Schaftingen, Emile; Letesson, Jean-Jacques

    2014-12-16

    Erythritol is an important nutrient for several α-2 Proteobacteria, including N2-fixing plant endosymbionts and Brucella, a worldwide pathogen that finds this four-carbon polyol in genital tissues. Erythritol metabolism involves phosphorylation to L-erythritol-4-phosphate by the kinase EryA and oxidation of the latter to L-3-tetrulose 4-phosphate by the dehydrogenase EryB. It is accepted that further steps involve oxidation by the putative dehydrogenase EryC and subsequent decarboxylation to yield triose-phosphates. Accordingly, growth on erythritol as the sole C source should require aldolase and fructose-1,6-bisphosphatase to produce essential hexose-6-monophosphate. However, we observed that a mutant devoid of fructose-1,6-bisphosphatases grew normally on erythritol and that EryC, which was assumed to be a dehydrogenase, actually belongs to the xylose isomerase superfamily. Moreover, we found that TpiA2 and RpiB, distant homologs of triose phosphate isomerase and ribose 5-phosphate isomerase B, were necessary, as previously shown for Rhizobium. By using purified recombinant enzymes, we demonstrated that L-3-tetrulose-4-phosphate was converted to D-erythrose 4-phosphate through three previously unknown isomerization reactions catalyzed by EryC (tetrulose-4-phosphate racemase), TpiA2 (D-3-tetrulose-4-phosphate isomerase; renamed EryH), and RpiB (D-erythrose-4-phosphate isomerase; renamed EryI), a pathway fully consistent with the isotopomer distribution of the erythrose-4-phosphate-derived amino acids phenylalanine and tyrosine obtained from bacteria grown on (13)C-labeled erythritol. D-erythrose-4-phosphate is then converted by enzymes of the pentose phosphate pathway to glyceraldehyde 3-phosphate and fructose 6-phosphate, thus bypassing fructose-1,6-bisphosphatase. This is the first description to our knowledge of a route feeding carbohydrate metabolism exclusively via D-erythrose 4-phosphate, a pathway that may provide clues to the preferential metabolism of

  17. The effect of different phosphate ion concentrations and ph of the phosphate buffer on lipase bioproduction by rhizopus oligosporus

    International Nuclear Information System (INIS)

    In the present investigation, we report the effect of phosphate ion concentration and different ph of the phosphate buffer (as diluent) on lipase bioproduction by Rhizopus oligosporus. For this purpose, solid state fermentation was employed. Different agricultural by-products such as wheat bran, rice husk, almond meal, soybean meal and sunflower meal were used as substrate. The maximum lipase activity (72.60 U/g) was observed with the almond meal. Addition of phosphate ions (K/sub 2/HPO/sub 4/) influenced the lipase production. The ph of the phosphate buffer (7.0) was found to be effective for higher yield of lipase. (author)

  18. Standard characterization of phosphate rock samples from the FAO/IAEA phosphate project

    International Nuclear Information System (INIS)

    Phosphate rocks (PR) are phosphate-bearing minerals that vary widely in their inherent characteristics and consequently their agronomic potential. In the framework of a FAO/IAEA networked research project, the evaluation of the agronomic effectiveness of natural and modified PR products under a variety of soil climate and crop management conditions was carried out. The characterization of phosphate rocks is the first and essential step in evaluating their suitability for direct application. If several PR sources are utilized, standardized methods should be used for comparison purposes to determine their agronomic potential. This paper describes the standard characterization of phosphate rock products utilized in the project, in particular the mineralogical and crystallographic analyses, physical analyses, chemical composition and solubility in conventional reagents. A total of 28 phosphate rock samples from 15 countries were collected and analyzed in specialized laboratories. The data on mineralogy, chemical composition and solubility in conventional reagents are closely interrelated. An arbitrary classification of the reactivity of the PR samples was made based on the solubility indices in conventional reagents. On another hand, the results of the crystallographic parameters, calculated indices of absolute solubility, specific surface and porosity reflect the variability of the physical state and the sample pre-conditioning treatment of the analyzed products. A proper characterization of phosphate rock samples should provide the maximum of basic information that can be obtained in a cost-effective manner in normal chemical laboratories. Based on the results of this characterization, the following determinations are recommended: a description of the sample, major elemental (total P, Ca, Mg) composition, solubility in conventional reagents (neutral ammonium citrate, citric and formic acid) and particle size analysis. The classification of PR samples for direct

  19. Osteogenecity of octacalcium phosphate coatings applied on porous metal implants

    NARCIS (Netherlands)

    Barrere, Florence; Valk, van der Chantal M.; Dalmeijer, Remco A.J.; Meijer, Gert; Blitterswijk, van Clemens A.; Groot, de Klaas; Layrolle, Pierre

    2003-01-01

    The biomimetic route allows the homogeneous deposition of calcium phosphate (Ca-P) coatings on porous implants by immersion in simulated physiologic solution. In addition, various Ca-P phases, such as octacalcium phosphate (OCP) or bone-like carbonated apatite (BCA), which are stable only at low tem

  20. The Vale de Abrutiga uranium phosphates mine, central Portugal

    OpenAIRE

    Pinto, Marina M. S. Cabral; Silva, Maria M. V. G.

    2007-01-01

    A brief summary about the composition and origins of the U deposit is present. The mineralization is composed by secondary uranium phosphates (saleeite and meta-saleeite). The precipitation was probably the main responsible factor for U retention within the quartz veins leading to the uranium phosphate mineralization of Vale de Abrutiga.

  1. Phosphate retention by soil in relation to waste disposal

    NARCIS (Netherlands)

    Beek, J.

    1979-01-01

    The disposal of large amounts of domestic sewage water and liquid manure, both containing dissolved phosphates, is often problematic. Discharge of these into (shallow and standing) surface waters is highly undesirable, as phosphate is considered to be one of the prime causes of eutrophication. If, o

  2. Corrosion resistance of phosphated steels with plasma sprayed ceramic coatings

    Czech Academy of Sciences Publication Activity Database

    Brožek, Vlastimil; Mastný, L.; Pokorný, P.

    Zagreb: Croatian Metallurgical Society (CMS), 2014 - (Mamuzić, I.). s. 401 ISBN N. [International Symposium of Croatian Metallurgical Society SHMD 2014/11./. 22.06.2014-26.06.2014, Šibenik] Institutional support: RVO:61389021 Keywords : steel phosphating * phosphate coatings * plasma spraying * ceramic coatings * corrosion resistance * bond strength of coatings Subject RIV: CA - Inorganic Chemistry

  3. Intercalation chemistry of layered vanadyl phosphate: a review

    Czech Academy of Sciences Publication Activity Database

    Beneš, L.; Melánová, Klára; Svoboda, Jan; Zima, Vítězslav

    2012-01-01

    Roč. 73, 1-4 (2012), 33-53. ISSN 0923-0750 Institutional research plan: CEZ:AV0Z40500505 Keywords : vanadyl phosphate * intercalation * layered phosphates Subject RIV: CA - Inorganic Chemistry Impact factor: 1.399, year: 2012

  4. Silver(I) sorption on zirconium phosphate ion exchangers

    International Nuclear Information System (INIS)

    This article is devoted to silver sorption on zirconium phosphate ion exchangers. Thus, the sorption of silver from nitrate and ammoniac solutions on three component ion exchangers is studied. Influence of ph on sorption of zirconium phosphates is studied as well.

  5. Metal Phosphates as Intermediate Temperature Proton Conducting Electrolytes

    DEFF Research Database (Denmark)

    Huang, Yunjie; Li, Q.F.; Pan, Chao;

    2012-01-01

    A series of metal phosphates were synthesized and screened as potential proton conductor electrolytes for fuel cells and electrolysers operational at intermediate temperatures. Among the selected, niobium and bismuth phosphates exhibited a proton conductivity of 10-2 and 10-7 S cm-1, respectively...

  6. Effect of humic substances on the precipitation of calcium phosphate

    Institute of Scientific and Technical Information of China (English)

    SONG Yong-hui; Hermann H. HAHN; Erhard HOFFMANN; Peter G. WEIDLER

    2006-01-01

    For phosphorus (P) recovery from wastewater, the effect of humic substances (HS) on the precipitation of calcium phosphate was studied. Batch experiments of calcium phosphate precipitation were undertaken with synthetic water that contained 20 mg/L phosphate (as P) and 20 mg/L HS (as dissolved organic carbon, DOC) at a constant pH value in the range of 8.0-10.0. The concentration variations of phosphate, calcium (Ca) and HS were measured in the precipitation process; the crystalline state and compositions of the precipitates were analysed by powder X-ray diffraction (XRD) and chemical methods, respectively. It showed that at solution pH 8.0, the precipitation rate and removal efficiency of phosphate were greatly reduced by HS, but at solution pH ≥9.0,the effect of HS was very small. The Ca consumption for the precipitation of phosphate increased when HS was added; HS was also removed from solution with the precipitation of calcium phosphate. At solution pH 8.0 and HS concentrations ≤ 3.5 mg/L, and at pH ≥ 9.0 and HS concentrations ≤ 10 mg/L, the final precipitates were proved to be hydroxyapatite (HAP) by XRD. The increases of solution pH value and initial Ca/P ratio helped reduce the influence of HS on the precipitation of phosphate.

  7. 40 CFR 721.6005 - Rare earth phosphate (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Rare earth phosphate (generic). 721... Substances § 721.6005 Rare earth phosphate (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as rare earth phophate (PMNs...

  8. Mercury stabilization in chemically bonded phosphate ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Wagh, A. S.; Singh, D.; Jeong, S. Y.

    2000-04-04

    Mercury stabilization and solidification is a significant challenge for conventional stabilization technologies. This is because of the stringent regulatory limits on leaching of its stabilized products. In a conventional cement stabilization process, Hg is converted at high pH to its hydroxide, which is not a very insoluble compound; hence the preferred route for Hg sulfidation to convert it into insoluble cinnabar (HgS). Unfortunately, efficient formation of this compound is pH-dependent. At a high pH, one obtains a more soluble Hg sulfate, in a very low pH range, insufficient immobilization occurs because of the escape of hydrogen sulfide, while efficient formation of HgS occurs only in a moderately acidic region. Thus, the pH range of 4 to 8 is where stabilization with Chemically Bonded Phosphate Ceramics (CBPC) is carried out. This paper discusses the authors experience on bench-scale stabilization of various US Department of Energy (DOE) waste streams containing Hg in the CBPC process. This process was developed to treat DOE's mixed waste streams. It is a room-temperature-setting process based on an acid-base reaction between magnesium oxide and monopotassium phosphate solution that forms a dense ceramic within hours. For Hg stabilization, addition of a small amount (< 1 wt.%) of Na{sub 2}S or K{sub 2}S is sufficient in the binder composition. Here the Toxicity Characteristic Leaching Procedure (TCLP) results on CBPC waste forms of surrogate waste streams representing secondary Hg containing wastes such as combustion residues and Delphi DETOX{trademark} residues are presented. The results show that although the current limit on leaching of Hg is 0.2 mg/L, the results from the CBPC waste forms are at least one order lower than this stringent limit. Encouraged by these results on surrogate wastes, they treated actual low-level Hg-containing mixed waste from their facility at Idaho. TCLP results on this waste are presented here. The efficient stabilization

  9. Mercury stabilization in chemically bonded phosphate ceramics

    International Nuclear Information System (INIS)

    Mercury stabilization and solidification is a significant challenge for conventional stabilization technologies. This is because of the stringent regulatory limits on leaching of its stabilized products. In a conventional cement stabilization process, Hg is converted at high pH to its hydroxide, which is not a very insoluble compound; hence the preferred route for Hg sulfidation to convert it into insoluble cinnabar (HgS). Unfortunately, efficient formation of this compound is pH-dependent. At a high pH, one obtains a more soluble Hg sulfate, in a very low pH range, insufficient immobilization occurs because of the escape of hydrogen sulfide, while efficient formation of HgS occurs only in a moderately acidic region. Thus, the pH range of 4 to 8 is where stabilization with Chemically Bonded Phosphate Ceramics (CBPC) is carried out. This paper discusses the authors experience on bench-scale stabilization of various US Department of Energy (DOE) waste streams containing Hg in the CBPC process. This process was developed to treat DOE's mixed waste streams. It is a room-temperature-setting process based on an acid-base reaction between magnesium oxide and monopotassium phosphate solution that forms a dense ceramic within hours. For Hg stabilization, addition of a small amount (2S or K2S is sufficient in the binder composition. Here the Toxicity Characteristic Leaching Procedure (TCLP) results on CBPC waste forms of surrogate waste streams representing secondary Hg containing wastes such as combustion residues and Delphi DETOXtrademark residues are presented. The results show that although the current limit on leaching of Hg is 0.2 mg/L, the results from the CBPC waste forms are at least one order lower than this stringent limit. Encouraged by these results on surrogate wastes, they treated actual low-level Hg-containing mixed waste from their facility at Idaho. TCLP results on this waste are presented here. The efficient stabilization in all these cases is attributed

  10. Occupational dose from natural radionuclides in phosphate fertilizers

    International Nuclear Information System (INIS)

    In this investigation the occupational exposure of single persons due to the gamma radiation of the natural radionuclides in rock phosphates and phosphate fertilizers and their contribution to the population dose in the FRG has been determined. The exposure rates in the working fields production, transport, loading and storage of rock phosphates and phosphate fertilizers and due to their application in agriculture have been measured by means of scintillation dose rate meters or LiF-thermoluminescence dosemeters or have been estimated from specific activities. This investigation shows that an occupational radiation exposure of individuals may occur which corresponds to the mean terrestrial radiation exposure in the FRG. The contribution of the occupational collective doses due to phosphates to the population dose, however, is negligibly small. (orig.)

  11. Cathodic phosphate coating containing nano zinc particles on magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A technology for preparation of a cathodic phosphate coating mainly containing nano metallic zinc particles and phosphate compounds on magnesium alloy was developed.The influence of cathodic current density on the microstructure of the cathodic phosphate coating Was investigated.The results show that the crystals of the coating are finer and the microstructures of the outer surface of the coatings are zigzag at the cathodic density of 0.2-0.5 A/dm2.The content of nano metallic zinc particles in the coating decreases with the increase of the thickness of the coatings and tends to be zero when the coating thickness is 4.14 μm.The cathodic phosphate coating was applied to be a transition coating for improving the adhesion between the paints and the magnesium alloys.The formation mechanism of the cathodic phosphate coating was investigated as well.

  12. Isolation of phosphate solubiliser fungi from Araza rhizosphere

    International Nuclear Information System (INIS)

    Araza is an eatable plant, original from the Amazon region, which has been described as a promising species for commercialization (Quevedo 1995). This plant has high productivity even in low content phosphate soil but the presence of phosphate solubilizing microorganisms may contribute to increase this element availability. In this study we report the isolation and characterization of solubilizing fungi processed using the soil washing method, from soil samples were araza is cultivated at two regions in Guaviare, Colombia. Eighteen isolates of fungi capable of solubilizing phosphate were obtained from 2 different sources. The most important species that solubilized phosphate from calcium were Trichoderma aureoviride, Aspergillus aculeatus, Trichoderma strain 1 y Trichoderma strain 2 and for phosphate from iron: Aspergillus oryzae, Paecilomyces strain 3, Gongronella butleri and Fusarium oxysporum

  13. EFFECT OF SODIUM PHOSPHATES ON SELECTED FOOD GRADE BACTERIA

    Directory of Open Access Journals (Sweden)

    Stanislav Kráčmar

    2011-04-01

    Full Text Available The aim of this study was to examine the inhibitory effect in vitro of selected sodium phosphates (under the corporate names Hexa 68, Hexa 70, Trikrystal, FST, Pyro 52, KPS, Didi on selected gram-positive and gram-negative bacteria. Seven different concentrations of each phosphate were used. Sensitivity of the bacterial strains to phosphates was observed in broth supplemented with salts. In vitro was showed a negative effect of various phosphates on growth of selected gram-positive bacteria. Orthophosphates and diphosphates (pyrophosphates did not have significant inhibitory effect on tested bacteria at neutral pH. With the exception of phosphate Trikrystal has not been found in vitro significant inhibitory effects on gram-negative bacteria.doi:10.5219/141

  14. Injectable bioactive calcium-magnesium phosphate cement for bone regeneration

    International Nuclear Information System (INIS)

    Novel injectable and degradable calcium-magnesium phosphate cement (CMPC) with rapid-setting characteristic was developed by the introduction of magnesium phosphate cement (MPC) into calcium phosphate cement (CPC). The calcium-magnesium phosphate cement prepared under the optimum P/L ratio exhibited good injectability and desired workability. It could set within 10 min at 37 0C in 100% relative humidity and the compressive strength could reach 47 MPa after setting for 48 h, indicating that the prepared cement has relatively high initial mechanical strength. The results of in vitro degradation experiments demonstrated the good degradability of the injectable CMPC, and its degradation rate occurred significantly faster than that of pure CPC in simulated body fluid (SBF) solution. It can be concluded that the novel injectable calcium-magnesium phosphate cement is highly promising for a wide variety of clinical applications, especially for the development of minimally invasive techniques.

  15. Bioavailabilty of deposit phosphates in animal feeding

    International Nuclear Information System (INIS)

    In order to evaluate the growth, the absorption and the dynamics of phosphorus and calcium phosphates of high fluorine content , triple superphosphates (TSP) and two sedimentary phosphates Riecito (RIO) and Monte Fresco (MONTE) vs dicalcium phosphate (DICAL), they were carried out two experiments with sheep. In the first one, with a duration of 360 days, the group (six animals) consumed DICAL, and at the 330 day of feeding it was divided in two groups, one under the same treatment and to the other one it was added 500 ppm of fluorine like NaF (DICAL+F). In this experiment the growth was evaluated, and at the end of the period, it was determined the phosphorus and calcium absorption and kinetics, the retention of fluorine in different sources, as well as the bony mineralization. In the second experiment, with a duration of 30 days, the phosphorus absorption and kinetics, as and the retention of fluorine in the sources under study, were determined. In both experiments, for the dynamic studies it was used the isotopic dilution technique, by means of the dosage, through jugular injection, of 200 uCi 32P and, for via oral, 200 uCi 45Ca. The weight gained (g / animal /day ) was 75, 87, 56 and 53 for DICAL, RIO, MONTE and TSP, respectively, with significant differences (P'0.05) in favor of DICAL and RIO. The true absorption of phosphorus (%), for the fed animals during 30 and 360 days, respectively, was 73 and 76 for DICAL, 40 and 57 for RIO, 36 and 57 for MONTE and, 79 and 71 for TSP, being significantly higher (P'0.05), for both periods, the values of DICAL and TSP. The evaluation of 12 months of absorption of RIVER and MONTE was higher than during the period of 30 days. The absorption of calcium at the 362 days was higher for DICAL and RIO in relation to MONTE and TSP. The addition of fluorine during 30 days didn't affect the calcium and phosphorus absorption. The run time to reach the maximum level of specific activity of calcium in blood was higher for RIO, MONTE and

  16. Radiation exposure levels in phosphate mining activities

    International Nuclear Information System (INIS)

    Radon, radon daughter concentration and gamma ray exposure rate were measured at different places in the phosphate mining areas of Syria. The grab sampling method was used. For radon measurements, discrete air samples without progeny were collected over short periods of time, whereas daughters were collected on filter paper. A three-count procedure was used for the measurement of radon daughter concentrations to improve accuracy. The measurements were carried out at 37 locations selected in the mines, factories, offices and homes in the mining area. The sampling was repeated monthly for a full calendar year. Workers and their families were classified in different categories according to the nature of their jobs. The doses were estimated using proper occupancy factors. The dose equivalent from radon daughters varies from 1 mSv.y-1 to a maximum of 10 mSv.y-1. Radon concentrations vary from 100 Bq.m-3 to several hundreds. (author)

  17. Thermal Decomposition of Nitrated Tributyl Phosphate

    International Nuclear Information System (INIS)

    Contact between tributyl phosphate and aqueous solutions of nitric acid and/or heavy metal nitrate salts at elevated temperatures can lead to exothermic reactions of explosive violence. Even though such operations have been routinely performed safely for decades as an intrinsic part of the Purex separation processes, several so-called ''red oil'' explosions are known to have occurred in the United States, Canada, and the former Soviet Union. The most recent red oil explosion occurred at the Tomsk-7 separations facility in Siberia, in April 1993. That explosion destroyed part of the unreinforced masonry walls of the canyon-type building in which the process was housed, and allowed the release of a significant quantity of radioactive material

  18. New light on phosphate transfer from triesters.

    Science.gov (United States)

    Kirby, Anthony J; Mora, José R; Nome, Faruk

    2013-01-01

    The reactivity of triesters is discussed in the general context of phosphate transfer, as usually studied for the reactions of mono- and diesters. Systematic work has typically concentrated on the Linear Free Energy Relationships measuring the dependence of reactivity on the nucleophile and the leaving group, but new results indicate that it can depend equally strongly on the two non-leaving (sometimes known as spectator) groups. This conclusion is supported by first results from theoretical calculations: which also predict that a two-step mechanism can be favored over a concerted S(N)2(P) mechanism even for reactions involving leaving groups as good as p-nitrophenolate. This article is part of a Special Issue entitled: Chemistry and mechanism of phosphatases, diesterases and triesterases. PMID:22575086

  19. Antiferroelectric films of deuterated betaine phosphate

    Science.gov (United States)

    Balashova, E. V.; Krichevtsov, B. B.; Svinarev, F. B.; Zaitseva, N. V.

    2016-07-01

    Thin films of partially deuterated betaine phosphate have been grown by the evaporation on Al2O3(110) and NdGaO3(001) substrates with a preliminarily deposited structure of interdigitated electrodes. The grown films have a polycrystalline block structure with characteristic dimensions of blocks of the order of 0.1-1.5 mm. The degree of deuteration of the films D varies in the range of 20-50%. It has been found that, at the antiferroelectric phase transition temperature T c afe = 100-114 K, the fabricated structures exhibit an anomaly of the electrical capacitance C, which is not accompanied by a change in the dielectric loss tangent tanδ. The strong-signal dielectric response is characterized by the appearance of a ferroelectric nonlinearity at temperatures T > T c afe , which is transformed into an antiferroelectric nonlinearity at T diagram has been constructed.

  20. Study of some properties of zirconium phosphate

    International Nuclear Information System (INIS)

    Zirconium phosphate has been studied with a view to using it as an ion exchanger: the first objective was to develop a method of preparation easy to apply and also reproducible. To this end, several tests were carried out varying the molar ratios of phosphorus and of zirconium. Some physical properties such as the diffraction of X-rays were examined. The work then involved certain chemical properties, particularly the percentages of free water and structural water given by the loss on calcination, the Karl-Fisher method and the weight losses by thermogravimetry. Finally an attempts was made to apply the exchanger to the separation of alkaline ions. The static tests showed that the order of fixation of these ions was Cs+ > Rb+ >> K+ > Na+. Tests with columns showed that Na+ and K+ were easily separable, as was the Rb+-Cs+ mixture, this last pair being fairly difficult to dissociate. (author)

  1. Use of phosphate rocks for sustainable agriculture

    International Nuclear Information System (INIS)

    This publication deals with the direct application of phosphate rock (PR) sources to agriculture. Phosphorus (P) is an essential plant nutrient and its deficiency restricts crop yields severely. Tropical and subtropical soils are predominantly acidic, and often extremely P deficient with high P-sorption (fixation) capacities. Therefore, substantial P inputs are required for optimum plant growth and adequate food and fibre production. Manufactured water-soluble P fertilizers such as superphosphates are commonly recommended to correct P deficiencies, but most developing countries import these fertilizers, which are often in limited supply and represent a major outlay for resource-poor farmers. In addition, intensification of agricultural production in these countries necessitates the addition of P not only to increase crop production but also to improve soil P status in order to avoid further soil degradation. Hence, it is imperative to explore alternative P sources. Under certain soil and climate conditions, the direct application of PR, especially where available locally, has proved to be an agronomically and economically sound alternative to the more expensive superphosphates. PR deposits occur worldwide, but few are mined (for use mainly as raw materials to manufacture water-soluble P fertilizers). The Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture initiated a Coordinated Research Project called 'The use of nuclear and related techniques for evaluating the agronomic effectiveness of phosphatic fertilizers, in particular rock phosphates'. This was implemented by institutes of developing and industrialized countries from 1993 to 1998. The results obtained yielded new information on: chemistry of soil P; tests for available soil P; phosphate nutrition of crops; agronomic effectiveness of PR products; and P fertilizer recommendations with particular emphasis on PR use. Within the framework of the integrated plant nutrition systems promoted by

  2. Atomic-level characterization of transport cycle thermodynamics in the glycerol-3-phosphate:phosphate antiporter

    Science.gov (United States)

    Moradi, Mahmoud; Enkavi, Giray; Tajkhorshid, Emad

    2015-09-01

    Membrane transporters actively translocate their substrate by undergoing large-scale structural transitions between inward- (IF) and outward-facing (OF) states (`alternating-access' mechanism). Despite extensive structural studies, atomic-level mechanistic details of such structural transitions, and as importantly, their coupling to chemical events supplying the energy, remain amongst the most elusive aspects of the function of these proteins. Here we present a quantitative, atomic-level description of the functional thermodynamic cycle for the glycerol-3-phosphate:phosphate antiporter GlpT by using a novel approach in reconstructing the free energy landscape governing the IFOF transition along a cyclic transition pathway involving both apo and substrate-bound states. Our results provide a fully atomic description of the complete transport process, offering a structural model for the alternating-access mechanism and substantiating the close coupling between global structural transitions and local chemical events.

  3. Study of the tributyl phosphate - 30% dodecane solvent; Etude du solvant phosphate tributylique - 30 % dodecane

    Energy Technology Data Exchange (ETDEWEB)

    Leroy, P. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses. Centre d' Etudes Nucleaires, 92 (France)

    1967-07-01

    This study, originating mainly from a literature survey, gives the principal chemical and physical features of the tributyl-phosphate (TBP) agent diluted at 30 volumes per cent in dodecane. The mixture is a very commonly used extractant in nuclear fuel processing. In this paper, the main following points are reported: -) the components (TBP and diluents) -) the TBP-diluents systems (non-loaded), -) the TBP-diluents-water systems, -) TBP-diluents-water-nitric acid systems, and -) industrial solvents. (author) [French] Cette etude, d'origine bibliographique, regroupe les caracteristiques physico-chimiques essentielles du phosphate tributylique (TBP) dilue a 30% en volume dans du dodecane. Ce melange constitue un agent d'extraction tres utilise dans le traitement des combustibles nucleaires. Les principaux points traites sont les suivants: -) les constituants (TBP et diluants), -) les systemes TBP-diluants non charges, -) les systemes TBP-diluants-eau, -) les systemes TBP-diluants-eau-acide nitrique, et -) les solvants industriels. (auteur)

  4. Chemistry of tetravalent actinides phosphates. The thorium phosphate-diphosphate as immobilisation matrix of actinides

    International Nuclear Information System (INIS)

    The author presents in this document its scientific works from 1992 to 2001, in order to obtain the enabling to manage scientific and chemical researches at the university Paris Sud Orsay. The first part gives an abstract of the thesis on the characterizations, lixiviation and synthesis of uranium and thorium based phosphate matrix in the framework of the search for a ceramic material usable in the radioactive waste storage. The second part presents briefly the researches realized at the CEA, devoted to a reliable, independent and accurate measure of some isotopes activity. The last part presents the abstracts of researches activities from 1996 to 2001 on the tetravalent actinides phosphates chemistry, the sintering of PDT and solid solutions of PDTU and the kinetic and thermodynamical studies of the PDT dissolution. Many references and some publication in full text are provided. (A.L.B.)

  5. Exposure from an igneous phosphate mine operation

    International Nuclear Information System (INIS)

    The International Atomic Energy Agency Safety Series 115 and European Union Council Directive 96/29/EURATOM have changed the profile of radiation protection completely, increasing the regulatory awareness of natural radiation and the industries involved. Three major industries have been identified in terms of their scope and the materials handled as industries requiring further attention. They are the oil and gas industry, the zircon industry and the phosphate and fertilizer industry. The phosphate and associated fertilizer industry has an added complication, because it has two distinct sources of raw material, i.e. being of igneous or sedimentary origin. The sedimentary material has a dominant 238U series, with activities ranging from 1 Bq/g per isotope to as high as 5.7 Bq/g per isotope, but with negligible 232Th content. The igneous material of the Phalaborwa Complex has fairly low levels of 238U and its associated daughters, (less than 0.15 Bq/g per isotope), but with elevated levels of 232Th when compared with the sedimentary material. This paper will focus on the mining operations of an igneous source located in South Africa. The mine involved received a nuclear authorization in 1993 in terms of the Nuclear Energy Act, No 131 of 1993 and in the following years completed both occupational and public risk assessments as required by the authorization. This paper places emphasis on the public risk assessment completed in 1999 and the results of the subsequent routine monitoring programme, and expands on some of the practical problems the company had to deal with. The public risk assessment was conducted in an integrated manner, assessing doses to members of the public via the atmospheric, aquatic and secondary pathways by the Nuclear Energy Corporation of South Africa and the subsequent routine monitoring programme results evaluated and reported to the regulator by the company itself. Finally, a brief description of the current monitoring programme is given, with

  6. Ribose 5-Phosphate Isomerase B Knockdown Compromises Trypanosoma brucei Bloodstream Form Infectivity

    OpenAIRE

    Inês Loureiro; Joana Faria; Christine Clayton; Sandra Macedo-Ribeiro; Nuno Santarém; Nilanjan Roy; Anabela Cordeiro-da-Siva; Joana Tavares

    2015-01-01

    Ribose 5-phosphate isomerase is an enzyme involved in the non-oxidative branch of the pentose phosphate pathway, and catalyzes the inter-conversion of D-ribose 5-phosphate and D-ribulose 5-phosphate. Trypanosomatids, including the agent of African sleeping sickness namely Trypanosoma brucei, have a type B ribose-5-phosphate isomerase. This enzyme is absent from humans, which have a structurally unrelated ribose 5-phosphate isomerase type A, and therefore has been proposed as an attractive dru...

  7. Influence of phosphate supply on teichoic acid and teichuronic acid content of Bacillus subtilis cell walls.

    OpenAIRE

    Lang, W K; Glassey, K; Archibald, A R

    1982-01-01

    Bacillus subtilis 168 was grown in chemostat culture in fully defined media containing a constant concentration of magnesium and concentrations of phosphate that varied from those giving phosphate-limited growth to those in which phosphate was present in excess and magnesium was limiting. Phosphate-limited bacteria were deficient in wall teichoic acid and contained less than half as much cellular phosphate as did bacteria grown in excess of phosphate. Approximately 70% of the additional phosp...

  8. A phosphate-centric paradigm for pathophysiology and therapy of chronic kidney disease

    OpenAIRE

    Kuro-o, Makoto

    2013-01-01

    Extracellular phosphate is toxic to the cell at high concentrations. When the phosphate level is increased in the blood by impaired urinary phosphate excretion, premature aging ensues. When the phosphate level is increased in the urine by dietary phosphate overload, this may lead to kidney damage (tubular injury and interstitial fibrosis). Extracellular phosphate exerts its cytotoxicity when it forms insoluble nanoparticles with calcium and fetuin-A, referred to as calciprotein particles (CPP...

  9. Metal sulfide and rare-earth phosphate nanostructures and methods of making same

    Energy Technology Data Exchange (ETDEWEB)

    Wong, Stanislaus; Zhang, Fen

    2016-06-28

    The present invention provides a method of producing a crystalline rare earth phosphate nanostructure. The method comprising: providing a rare earth metal precursor solution and providing a phosphate precursor solution; placing a porous membrane between the metal precursor solution and the phosphate precursor solution, wherein metal cations of the metal precursor solution and phosphate ions of the phosphate precursor solution react, thereby producing a crystalline rare earth metal phosphate nanostructure.

  10. SPX1 is a phosphate-dependent inhibitor of PHOSPHATE STARVATION RESPONSE 1 in Arabidopsis

    OpenAIRE

    M.I. Puga; Mateos, I; R. Charukesi; Wang, Z.; Franco-Zorrilla, J.M.; Lorenzo, L; M.L. Irigoyen; Masiero, S; Bustos, R.; Rodríguez, J.; A. Leyva; V. Rubio; Sommer, H.; J. Paz-Ares

    2014-01-01

    When P levels are low, plants activate an array of adaptive responses to increase efficient acquisition and use of phosphate (Pi), the form in which P is preferentially absorbed, and to protect themselves from Pi starvation stress. Considerable progress has been made recently in dissecting the plant Pi starvation signaling pathway. Nonetheless, little is known as to how Pi levels are perceived by plants. Here, we identify the nuclear protein SPX1 as a Pi-dependent inhibitor of DNA binding by ...

  11. A phosphate-starvation-inducible outermembrane protein of Pseudomonas fluorescens Ag1 as an immunological phosphate-starvation marker

    DEFF Research Database (Denmark)

    Leopold, Kristine; Jacobsen, Susanne; Nybroe, Ole

    1997-01-01

    cell permeabilization was adapted to visualize cell-specificexpression of Psi1 in P. fluorescens exposed to limiting amounts of phosphate. This approach should be useful for further exploration of Psi1 as a marker to study the availability of phosphate to P. fluorescens in natural environments....

  12. Multiple independent fusions of glucose-6-phosphate dehydrogenase with enzymes in the pentose phosphate pathway.

    Directory of Open Access Journals (Sweden)

    Nicholas A Stover

    Full Text Available Fusions of the first two enzymes in the pentose phosphate pathway, glucose-6-phosphate dehydrogenase (G6PD and 6-phosphogluconolactonase (6PGL, have been previously described in two distant clades, chordates and species of the malarial parasite Plasmodium. We have analyzed genome and expressed sequence data from a variety of organisms to identify the origins of these gene fusion events. Based on the orientation of the domains and range of species in which homologs can be found, the fusions appear to have occurred independently, near the base of the metazoan and apicomplexan lineages. Only one of the two metazoan paralogs of G6PD is fused, showing that the fusion occurred after a duplication event, which we have traced back to an ancestor of choanoflagellates and metazoans. The Plasmodium genes are known to contain a functionally important insertion that is not seen in the other apicomplexan fusions, highlighting this as a unique characteristic of this group. Surprisingly, our search revealed two additional fusion events, one that combined 6PGL and G6PD in an ancestor of the protozoan parasites Trichomonas and Giardia, and another fusing G6PD with phosphogluconate dehydrogenase (6PGD in a species of diatoms. This study extends the range of species known to contain fusions in the pentose phosphate pathway to many new medically and economically important organisms.

  13. Viscosity and crystallization mechanism of cesium loaded iron phosphate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, Kitheri, E-mail: joskit@igcar.gov.in [Chemistry Group, IGCAR, Kalpakkam 603 102 (India); Kutty, K.V. Govindan [Chemistry Group, IGCAR, Kalpakkam 603 102 (India); Goswami, M.C. [National Metallurgical Laboratory, Jamshedpur 831 007 (India); Rao, P.R. Vasudeva [Chemistry Group, IGCAR, Kalpakkam 603 102 (India)

    2014-07-01

    Highlights: • Melt viscosity of cesium loaded iron phosphate glasses is measured and reported for the first time. • Viscosity – temperature followed Arrhenius model. • Activation energy of viscous flow is strongly correlated to glass transition temperature of the glasses. • Process of crystallization of cesium loaded glass by approximation-free kinetic method to understand the mechanism. • Cesium loaded IPG and IPG shows bulk crystallization mechanism. - Abstract: This paper describes the melt viscosity behaviour and the crystallization mechanism of a series of iron phosphate glasses. High temperature viscosity measurements were carried out on pristine iron phosphate glass and a series of cesium loaded iron phosphate glasses in order to understand the effect of addition of Cs{sub 2}O on viscosity of iron phosphate glasses. Activation energy of viscous flow was estimated from the experimental data by applying Arrhenius model of viscosity–temperature relationship. Activation energy of viscous flow is observed to be strongly correlated to glass transition temperature of these glasses. Fragility of iron phosphate and cesium loaded iron phosphate glass systems were also evaluated in region of high temperature. Crystallization of these glasses was studied using thermal analysis techniques. Temperature integral approximation free method was utilized to evaluate the kinetic parameters such as activation energy of crystallization (E{sub c}) and Avrami exponent (n). The value of Avrami exponent ‘n’ obtained showed that the glasses under present study crystallize via bulk crystallization mechanism, i.e., nucleation and three dimensional growth.

  14. Viscosity and crystallization mechanism of cesium loaded iron phosphate glasses

    International Nuclear Information System (INIS)

    Highlights: • Melt viscosity of cesium loaded iron phosphate glasses is measured and reported for the first time. • Viscosity – temperature followed Arrhenius model. • Activation energy of viscous flow is strongly correlated to glass transition temperature of the glasses. • Process of crystallization of cesium loaded glass by approximation-free kinetic method to understand the mechanism. • Cesium loaded IPG and IPG shows bulk crystallization mechanism. - Abstract: This paper describes the melt viscosity behaviour and the crystallization mechanism of a series of iron phosphate glasses. High temperature viscosity measurements were carried out on pristine iron phosphate glass and a series of cesium loaded iron phosphate glasses in order to understand the effect of addition of Cs2O on viscosity of iron phosphate glasses. Activation energy of viscous flow was estimated from the experimental data by applying Arrhenius model of viscosity–temperature relationship. Activation energy of viscous flow is observed to be strongly correlated to glass transition temperature of these glasses. Fragility of iron phosphate and cesium loaded iron phosphate glass systems were also evaluated in region of high temperature. Crystallization of these glasses was studied using thermal analysis techniques. Temperature integral approximation free method was utilized to evaluate the kinetic parameters such as activation energy of crystallization (Ec) and Avrami exponent (n). The value of Avrami exponent ‘n’ obtained showed that the glasses under present study crystallize via bulk crystallization mechanism, i.e., nucleation and three dimensional growth

  15. Diversity of Phosphate-Dissolving Microorganisms in Corn Rhizosphere

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xiao-rong; LIN Qi-mei; LI Bao-guo

    2003-01-01

    Rhizosphere and nonrhizopshere soils were sampled during corn growth. Total, inorganic phosphate-dissolving and lecithin-mineralizing bacteria, fungi and actinomyctes were determined by plate counting method. Generally, the rhizosphere soil contained around 5 to 100 times more of these bacteria and fungi than the non-rhizosphere soil. However, the actinomycetes in the rhizosphere soil were significantly lower than those in the non-rhizosphere soil. The numbers of these microorganisms didnt significantly change during corn growth in the soils. However, the proportion of the phosphate-dissolving microorganisms in the total changed markedly during corn growth. Generally there were much higher percentages of phosphate-dissolving bacteria and phosphate-dissolving fungi in the rhizosphere soil than the nonrhizosphere soil. More than 90% of the fungi in rhizosphere dissolved inorganic phosphate at the seedling period, but this proportion declined to 20 %at the harvesting time. The community of phosphate-dissolving microorganisms also changed during corn growth. Bacillus was dominant in the nonrhizosphere soil. However, in the rhizosphere, Pseudomonas and Enterobacter became predominant. Penicillium and Streptomyces were the main fungi and actinomycetes capable of dissolving phosphate.

  16. Phosphate solubilization characteristics of efficient nitrogen fixing soil Azotobacter strains.

    Directory of Open Access Journals (Sweden)

    Rahim Nosrati

    2014-08-01

    Full Text Available Azotobacter is a diazotroph bacterium reported to possess various plant growth-promoting characteristics.The aim of this study was to isolate Azotobacter strains capable of fixing nitrogen and effectively hydrolyzing both organic and inorganic Pi compounds.In this study, soil samples collected from a diverse range of slightly alkaline soil types were screened for Azotobacter isolates. The inorganic and organic phosphate solubilization potentials of twenty competent phosphate solubilizing Azotobacter isolates were assessed.Variations were noted in the solubilization potentials.Three isolates, identified as Azotobacter vinelandii strains O2, O4 and O6, were able to fix atmospheric N2 effectively. The nitrogenase activity of these isolates ranged between 158.6 and 326.4 C2H4h(-1vial(-1 (ethylene. Bacterial growth rates and phosphate solubilization activities were measured quantitatively under various environmental conditions. A close association was evident between phosphate solubilizing ability and growth rate as an indicator of active metabolism. All three phosphate solubilizing bacteria (PSB were able to withstand temperature as high as 45°C, high concentration of NaCl (upto 5% and a wide range of initial pH from 5 to 10 while hydrolyzing phosphate compounds actively.Azotobacter vinelandii strains O2, O4 and O6 are superior candidates for biofertilizers that may result in the reduction of chemical nitrogen and phosphate fertilizers leading to increase crop production.

  17. Phosphate Removal by Anion Binding on Functionalized Nanoporous Sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Chouyyok, Wilaiwan; Wiacek, Robert J.; Pattamakomsan, Kanda; Sangvanich, Thanapon; Grudzien, Rafal M.; Fryxell, Glen E.; Yantasee, Wasanna

    2010-03-26

    Phosphate was captured from aqueous solutions by cationic metal-EDA complexes anchored inside mesoporous silica MCM-41 supports (Cu(II)-EDA-SAMMS and Fe(III)-EDA-SAMMS). Fe-EDA-SAMMS was more effective at capturing phosphate than the Cu-EDA-SAMMS and was further studied for matrix effects (e.g., pH, ionic strength, and competing anions) and sorption performance (e.g., capacity and rate). The adsorption of phosphate was highly pH dependent; it increased with increasing pH from 1.0 to 6.5, and decreased above pH 6.5. The adsorption was affected by high ionic strength (0.1 M of NaCl). In the presence of 1000-fold molar excess of chloride and nitrate anions, phosphate removal by Fe-EDA-SAMMS was not affected. Slight, moderate and large impacts were seen with bicarbonate, sulfate and citrate anions, respectively. The phosphate adsorption data on Fe-EDA-SAMMS agreed well with the Langmuir model with the estimated maximum capacity of 43.3 mg/g. The material displayed rapid sorption rate (99% of phosphate removal within 1 min) and lowering the phosphate content to ~ 10 µg/L of phosphorus, which is lower than the EPA’s established freshwater contaminant level for phosphorous (20 µg/L).

  18. Iron Phosphate Glass Development and Demonstration (AJHM and CCIM)

    International Nuclear Information System (INIS)

    Iron phosphate glasses retain high concentrations of some waste components that are difficult to dissolve into borosilicate melts - Sulfates, phosphates, heavy metals (Cr, Bi, Mo) and halides (F, Cl). This translates into significant increases in waste loading (WL) or reduced canister counts for specific waste streams. Programmatic objectives are: (1) Develop phosphate glass systems at high waste loadings for Hanford LAW and other DOE HLWs (Hanford and INL); (2) Develop and demonstrate a process flowsheet for implementation of phosphate based glasses in melters (JHM or AJHM) similar to those currently employed at Hanford - Determine if an alternative melter (e.g., CCIM) could be used; (3) Determine potential benefits and costs for implementation of iron phosphate glasses into WTP; and (4) Begin the effort to qualify LAW-based iron phosphate glasses for disposal on site at Hanford. FY10 activities primarily focused on developing iron phosphate glasses for Hanford LAW immobilization. Iron phosphate glasses have been shown to retain high concentrations of some waste components that are difficult to dissolve into borosilicate melts - Sulfates, phosphates, heavy metals (Cr, Bi, Mo) and halides (F, Cl). FeP glasses may offer significant increases in waste loading (reduced canister counts) for specific waste streams. EM-31 FeP Team has developed an integrated program to assess the impact of implementing the FeP glass system on Hanford LAW/HLW vitrification facilities: (a) Glass formulation and optimization → high WLs for various waste streams, Hanford AZ-102 LAW primary focus of FY10; (b) Systems analysis → glass volumes or mass; (c) WTP flowsheet impacts → storage and transport issues; and (d) Long-term performance → support PA.

  19. Transformation of Phosphate Fertilizers with Different Solubilities in Calcareous Soils

    Institute of Scientific and Technical Information of China (English)

    JIANGBAI-FAN; GUYI-CHU; 等

    1993-01-01

    In this research work,the authors,using the recently developed method of fractionating the forms of inorganic phosphorus in calcareous soils,have studied the transformation processes of inorgnic phosphorus in three different phosphate fertilizers,i.e.,superphosphate,diammonium phosphate and calcium magnesium phyosphate,being commonly used in China,during a period of 3 years after their application to calcareous soils,and based on the experimental results obtained,some problems in current use of phosphate fertilizers are discussed.

  20. Iron phosphate materials as cathodes for lithium batteries

    CERN Document Server

    Prosini, Pier Paolo

    2011-01-01

    ""Iron Phosphate Materials as Cathodes for Lithium Batteries"" describes the synthesis and the chemical-physical characteristics of iron phosphates, and presents methods of making LiFePO4 a suitable cathode material for lithium-ion batteries. The author studies carbon's ability to increase conductivity and to decrease material grain size, as well as investigating the electrochemical behaviour of the materials obtained. ""Iron Phosphate Materials as Cathodes for Lithium Batteries"" also proposes a model to explain lithium insertion/extraction in LiFePO4 and to predict voltage profiles at variou

  1. Amine-intercalated α-zirconium phosphates as lubricant additives

    International Nuclear Information System (INIS)

    In this study, three types of amines intercalated α-zirconium phosphate nanosheets with different interspaces were synthesized and examined as lubricant additives to a mineral oil. Results from tribological experiments illustrated that these additives improved lubricating performance. Results of rheological experiments showed that the viscosity of the mineral oil was effectively reduced with the addition of α-zirconium phosphate nanosheets. The two-dimensional structure, with larger interspaces, resulting from amine intercalation, exhibited improved effectiveness in reducing viscosity. This study demonstrates that the nanosheet structure of α-zirconium phosphates is effective in friction reduction. The manufacture of lubricants with tailored viscosity is possible by using different intercalators

  2. Renal Phosphate Wasting in the Absence of Adenylyl Cyclase 6

    OpenAIRE

    Fenton, Robert A; Murray, Fiona; Dominguez Rieg, Jessica A.; Tang, Tong; Levi, Moshe; Rieg, Timo

    2014-01-01

    Parathyroid hormone (PTH) and fibroblast growth factor 23 (FGF-23) enhance phosphate excretion by the proximal tubule of the kidney by retrieval of the sodium-dependent phosphate transporters (Npt2a and Npt2c) from the apical plasma membrane. PTH activates adenylyl cyclase (AC) through PTH 1 receptors and stimulates the cAMP/PKA signaling pathway. However, the precise role and isoform(s) of AC in phosphate homeostasis are not known. We report here that mice lacking AC6 (AC6−/−) have increased...

  3. Effect of Phosphate on the Oxidation of Hydroxysulfate Green Rust

    Science.gov (United States)

    Benali, Omar; Abdelmoula, Mustapha; Génin, Jean.-Marie R.

    2005-04-01

    During Hydroxysulfate green rust GR(SO42) oxidation, lepidocrocite and goethite were formed. The oxidation of GR(SO42-) in the presence of phosphate ions, also involved the formation of poorly crystallized lepidocrocite but not that of goethite. The dissolution of lepidocrocite is inhibited by adsorption of phosphate ions as confirmed by X-ray photoelectron spectroscopy. The formation of the poorly crystallized protective layer against corrosion is effectively due to the phosphate ions which adsorb on the surface of lepidocrocite, and prevents it to turn into a well crystallized oxide.

  4. Fluorescence sensor for sequential detection of zinc and phosphate ions.

    Science.gov (United States)

    An, Miran; Kim, Bo-Yeon; Seo, Hansol; Helal, Aasif; Kim, Hong-Seok

    2016-12-01

    A new, highly selective turn-on fluorescent chemosensor based on 2-(2'-tosylamidophenyl)thiazole (1) for the detection of zinc and phosphate ions in ethanol was synthesized and characterized. Sensor 1 showed a high selectivity for zinc compared to other cations and sequentially detected hydrogen pyrophosphate and hydrogen phosphate. The fluorescence mechanism can be explained by two different mechanisms: (i) the inhibition of excited-state intramolecular proton transfer (ESIPT) and (ii) chelation-induced enhanced fluorescence by binding with Zn(2+). The sequential detection of phosphate anions was achieved by the quenching and subsequent revival of ESIPT. PMID:27343439

  5. [Isolation and identification of a novel phosphate-dissolving strain P21].

    Science.gov (United States)

    Yang, Hui; Fan, Bingquan; Gong, Mingbo; Li, Quanxia

    2008-01-01

    Phosphate-dissolving microorganisms can be applied for better use of insoluble phosphorus as fertilizer., A phosphate-dissolving strain P21 was isolated from soil samples in China. The isolate was identified as Erwinia herbicola var. ananas, based on its 16Sr DNA sequence and physiological characteristics. Its activity was measured in solid media as well as liquid media using different phosphate sources including tricalium phosphate, hydroxyapatite, ferric phosphate, aluminium phosphate, zinc phosphate, and rock phosphates. E. herbicola could strongly dissolve 1206.20 mg tricalium phosphate and 529.67 mg hydroxyapatite in per liter liquid media. The strain showed high phosphate-dissolving ability for rock phosphates from Jinning and Kunyang in Yunnan province, Yaan in Sichuan province and Jinping in Jiangsu province with the capacity of 6.64 mg, 78.46 mg, 67.07 mg and 65.24 mg soluble phosphate respectively per liter medium, whereas the phosphate-dissolving ability to the rest of the eight rock phosphates was weak. According to the experiments, the phosphate-dissolving ability of E. herbicola was specific to different rock phosphates, and phosphate-dissolving ability of E. herbicola was not directly related to pH reduction of liquid media. PMID:18338576

  6. [Screening, identification and phosphate-solubilizing characteristics of Rahnella sp. phosphate-solubilizing bacteria in calcareous soil].

    Science.gov (United States)

    Qiao, Zhi-wei; Hong, Jian-ping; Xie, Ying-he; Li, Lin-xuan

    2013-08-01

    Several strains of phosphate-solubilizing bacteria were isolated and screened from the crop rhizosphere of calcareous soil in Shanxi Province of China. After repeated isolation and purification, the strain W25 with strong phosphate-solubilizing activity was obtained, and identified as Rahnella sp., based on the morphological, physiological and biochemical properties and the analysis of 16S rRNA gene sequence. Further studies on the W25 showed that the maximum phosphate-solubilizing capability of the W25 on tricalium phosphate, aluminum phosphate and ferric phosphate reached 385.5, 110.4 and 216.6 mg x L(-1), respectively. In the liquid culture with aluminum phosphate and ferric phosphate, the solubilized phosphorous by the W25 was significantly negatively correlated with the liquid pH, with the correlation coefficient being 0.56 and 0.81, respectively. Among the carbon and nitrogen sources, glucose and ammonium nitrate were the optimum for the solubilization of tricalium phosphate by W25. The utilization of carbon source was in the order of glucose > lactose > sucrose > mannitose > starch, and that of nitrogen source was in the order of ammonium nitrate > ammonium chloride > ammonium sulfate > potassium nitrate > sodium nitrate. Different nitrogen sources had greater effects on the production of organic acids by W25. Formic acid and acetic acid would be produced when the nitrogen source was NH4+, oxalic acid and succinic acid would be produced when the nitrogen source was NO3(-), and citric acid would be extra produced when the ammonium nitrate was used as the nitrogen source. PMID:24380351

  7. Glucose 6 phosphate dehydrogenase deficiency in adults

    International Nuclear Information System (INIS)

    Objective: To determine the frequency of glucose-6-phosphate dehydrogenase (G6PD) deficiency in adults presented with anemia. Subjects and Methods: Eighteen months admission data was reviewed for G6PD deficiency as a cause of anemia. Anemia was defined by world health organization (WHO) criteria as haemoglobin less than 11.3 gm%. G6PD activity was measured by Sigma dye decolorisation method. All patients were screened for complications of hemolysis and its possible cause. Patients with more than 13 years of age were included in the study. Results: Out of 3600 patients admitted, 1440 were found anaemic and 49 as G6PD deficient. So the frequency of G6PD deficiency in anaemic patients was 3.4% and the overall frequency is 1.36%. G6PD deficiency among males and females was three and six percent respectively. Antimalarials and antibiotics containing sulphonamide group were the most common precipitating factors for hemolysis. Anemia and jaundice were the most common presentations while malaria was the most common associated disease. Acute renal failure was the most severe complication occurring in five patients with two deaths. Conclusion: G6PD deficiency is a fairly common cause of anemia with medicine as common precipitating factor for hemolysis. Such complications can be avoided with early recognition of the disease and avoiding indiscriminate use of medicine. (author)

  8. Formation and actions of inositol phosphates

    International Nuclear Information System (INIS)

    A wide variety of hormone and neurotransmitter receptors mediate control of cell function through activation of a phosphodiesteratic breakdown of polyphosphoinositides. In electrically permeabilized pancreatic acinar cells, non-hydrolyzable derivatives of GTP can activate this phosphodiesterase, and potentiate the action of hormones. This suggests receptor coupling to the enzyme probably involves a guanine nucleotide-dependent regulatory protein analogous to the ones involved in regulating adenylate cyclase. The water-soluble product of this reaction inositol-1,4,5-tris-phosphate [(1,4,5)IP3], signals Ca2+ release from a fraction of the endoplasmic reticulum which, in the liver, constitutes about 40% of the non-mitochondrial Ca2+ accumulating activity. By using a high specific activity 32P-labelled (1,4,5)IP3, a specific and saturable binding site for (1,4,5)IP3 can be demonstrated. Binding of (1,4,5)IP3 and (2,4,5)IP3 to this site is well correlated with the Ca2+-releasing actions of these molecules. This may indicate that the actions of (1,4,5)IP3 are mediated by a specific receptor on the endo- plasmic reticulum. The emptying of the sensitive Ca2+-pool in the endoplasmic reticulum by (1,4,5)IP3 may secondarily signal the influx of Ca2+ from the extracellular space

  9. Mercury stabilization in chemically bonded phosphate ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Wagh, Arun S.; Jeong, Seung-Young; Singh, Dileep

    1997-07-01

    We have investigated mercury stabilization in chemically bonded phosphate ceramic (CBPC) using four surrogate waste streams that represent U.S. Department of Energy (DOE) ash, soil, and two secondary waste streams resulting from the destruction of DOE`s high-organic wastes by the DETOX{sup SM} Wet Oxidation Process. Hg content in the waste streams was 0.1 to 0.5 wt.% (added as soluble salts). Sulfidation of Hg and its concurrent stabilization in the CBPC matrix yielded highly nonleachable waste forms. The Toxicity Characteristic Leaching Procedure showed that leaching levels were well below the U.S. Environmental Protection Agency`s regulatory limits. The American Nuclear Society`s ANS 16.1 immersion test also gave very high leaching indices, indicating excellent retention of the contaminants. In particular, leaching levels of Hg in the ash waste form were below the measurement detection limit in neutral and alkaline water, negligibly low but measureable in the first 72 h of leaching in acid water, and below the detection limit after that. These studies indicate that the waste forms are stable in a wide range of chemical environments during storage. 9 refs., 5 tabs.

  10. Mercury stabilization in chemically bonded phosphate ceramics

    International Nuclear Information System (INIS)

    We have investigated mercury stabilization in chemically bonded phosphate ceramic (CBPC) using four surrogate waste streams that represent U.S. Department of Energy (DOE) ash, soil, and two secondary waste streams resulting from the destruction of DOE's high-organic wastes by the DETOXSM Wet Oxidation Process. Hg content in the waste streams was 0.1 to 0.5 wt.% (added as soluble salts). Sulfidation of Hg and its concurrent stabilization in the CBPC matrix yielded highly nonleachable waste forms. The Toxicity Characteristic Leaching Procedure showed that leaching levels were well below the U.S. Environmental Protection Agency's regulatory limits. The American Nuclear Society's ANS 16.1 immersion test also gave very high leaching indices, indicating excellent retention of the contaminants. In particular, leaching levels of Hg in the ash waste form were below the measurement detection limit in neutral and alkaline water, negligibly low but measureable in the first 72 h of leaching in acid water, and below the detection limit after that. These studies indicate that the waste forms are stable in a wide range of chemical environments during storage. 9 refs., 5 tabs

  11. Sphingosine-1-Phosphate Signaling in Endothelial Disorders.

    Science.gov (United States)

    Sanchez, Teresa

    2016-06-01

    Numerous preclinical studies indicate that sustained endothelial activation significantly contributes to tissue edema, perpetuates the inflammatory response, and exacerbates tissue injury ultimately resulting in organ failure. However, no specific therapies aimed at restoring endothelial function are available as yet. Sphingosine-1-phosphate (S1P) is emerging as a potent modulator of endothelial function and endothelial responses to injury. Recent studies indicate that S1PR are attractive targets to treat not only disorders of the arterial endothelium but also microvascular dysfunction caused by ischemic or inflammatory injury. In this article, we will review the current knowledge of the role of S1P and its receptors in endothelial function in health and disease, and we will discuss the therapeutic potential of targeting S1PR not only for disorders of the arterial endothelium but also the microvasculature. The therapeutic targeting of S1PR in the endothelium could help to bridge the gap between biomedical research in vascular biology and clinical practice. PMID:27115142

  12. Thermoluminescence in calcium phosphate doped with samarium

    International Nuclear Information System (INIS)

    Calcium phosphate is a main constitutional substance of human bones and teeth, and it seems worthwhile to investigate the thermoluminescence (TL) characteristics after X-ray irradiation at room temperature. It has been reported that there are two crystal modifications for the corresponding compounds, one rhombohedral and the other having a monoclinic lattice (α- and β-phase, respectively), and α-Ca3(PO4)2 is produced by heating the β-phase. However, it was rather difficult to get the former phase completely 100% from the latter only by heating. With the TL glow curves used for dosimetry it is generally required that a main isolated glow peak should be located at rather high-temperature regions, in order to avoid fading during the keeping of the irradiated materials at room temperature. It is the purpose of the present work to obtain a stable TL dosimeter peak by using β-Ca3(PO4)2, the raw material of which can be obtained directly from any chemical company. According to our preliminary experiments doping various activators into the β-Ca3(PO4)2, it was found that the addition of Sm2O3 into the raw material gives rise to a satisfactory result, and in this paper we describe the case in detail. (Author)

  13. [Sphingosine-1-phosphate--molecular maestro].

    Science.gov (United States)

    Salata, Daria; Budkowska, Marta; Dołegowska, Barbara

    2012-01-01

    Sphingosine-1-phosphate (S1P), which is a bioactive lipid from the family of sphingolipids is synthesized i.e. by platelates and stored in erythrocytes. The effects of this compound on the cells are connected with the presence of specific receptors on their surface (S1P1-S1P5). S1P acts upon, i.e, hematopoetic and nervous cells, having influencing their migration, adhesion, differentation and survival. This molecule plays mediator role in inflammatory responses, angiogenesis and wound healing. In contrast to spingosine and ceramid, S1P counteracts apoptosis. Recent studies have shown that S1P is a factor, which participates in the process of release stem cells from bone marrow to peripherial blood. Cell and tissue damaged, stress, physical exercise and some drugs have influence on the numbers of stem cells. The research on S1P as the main chemotactic factor for stem cells may have substantial impact on the development of regenerative medicine. PMID:23373414

  14. Separation of tributyl phosphate from degraded solvents

    International Nuclear Information System (INIS)

    A solvent extraction method is described for the recovery of tributyl phosphate (TBP) from degraded process solvents. The method involves the separation of TBP and shell solT(SST) from 30% TBP/SSP mixture by thorium nitrate extraction leading to the formation of a heavy phase (third phase) which contains essentially TBP. The equilibrium experiments revealed that by utilizing thorium feeds of concentrations above 525 g/L in water at 1:1 ratio, a 30% TBP/SST mixture can be effectively separated into TBP and SST fractions with light SST phase having about 3% TBP. Using single stage mixer settler experiments, the feasibility of continuous separation of the three phases was assessed. Since there is a tendency for the degraded products of the diluent to seek the TBP phase, additional treatment steps would be necessary for their removal if the TBP is to be reused. Activated charcoal was investigated for this purpose. If purification of the TBP is not envisaged the volume of the organic waste generated in processing plants could be reduced by separating the diluent and TBP and only the TBP could be sent as concentrated waste. (author)

  15. Hypoxia, therapeutic resistance, and sphingosine 1-phosphate.

    Science.gov (United States)

    Cuvillier, Olivier; Ader, Isabelle; Bouquerel, Pierre; Brizuela, Leyre; Gstalder, Cécile; Malavaud, Bernard

    2013-01-01

    Hypoxia, defined as a poor oxygenation, has been long recognized as a hallmark of solid tumors and a negative prognostic factor for response to therapeutics and survival of patients. Cancer cells have evolved biochemical mechanisms that allow them to react and adapt to hypoxia. At the cellular level, this adaptation is under the control of two related transcription factors, HIF-1 and HIF-2 (hypoxia-inducible factor), that respond rapidly to decreased oxygen levels to activate the expression of a broad range of genes promoting neoangiogenesis, glycolysis, metastasis, increased tumor growth, and resistance to treatments. Recent studies have identified the sphingosine kinase 1/sphingosine 1-phosphate (SphK1/S1P) signaling pathway-which elicits various cellular processes including cell proliferation, cell survival, or angiogenesis-as a new regulator of HIF-1 or HIF-2 activity. In this review, we will focus on how the inhibition/neutralization of the SphK1/S1P signaling could be exploited for cancer therapy. PMID:23290779

  16. Dissolution kinetics of calcium phosphate coatings.

    Science.gov (United States)

    Burke, E M; Lucas, L C

    1998-01-01

    Plasma spray and high velocity oxy-fuel (HVOF) techniques produce coatings with varying composition and amounts of amorphous and crystalline phases. For coatings containing greater amorphous phases, a higher release of calcium ions is evident when samples are placed in Hank's calcium-free balanced salt solutions. Calcium is released from the amorphous phases in the coating, a conclusion that is supported by x-ray powder diffraction (XRD) results. Ion beam sputtering and RF magnetron sputtering under lower energy conditions produce amorphous coatings that will dissolve in a very short time period. When heat treated, crystalline phases are produced in the coatings. Heat-treated coatings are significantly more stable than the amorphous coatings. The dissolution rates of both amorphous and crystalline coatings produced by RF magnetron sputtering have been measured under constant solution conditions at pH 6.50. No reprecipitation is possible under these conditions. The amorphous coating dissolved at a significantly higher rate than the heat-treated coating. Reprecipitation of calcium phosphate onto amorphous coatings is possible in a physiological pH solution. Under these conditions, the dissolution rate of the amorphous coating is four times slower than at the pH 6.50 conditions. PMID:10196809

  17. Intercalation of lactones into vanadyl phosphate

    Science.gov (United States)

    Melánová, Klára; Beneš, Ludvík; Svoboda, Jan; Zima, Vítězslav

    2006-05-01

    Intercalates of vanadyl phosphate with α-methyl-γ-butyrolactone, γ-valerolactone, γ-caprolactone, δ-valerolactone, and ɛ-caprolactone were prepared by a displacement reaction of ethanol-intercalated VOPO4. As follows from the results of elemental analyses and thermogravimetry, intercalates contain about one molecule of the guest per formula unit. The diffractograms of the intercalates show a series of sharp (001) reflections, (200) reflection and some (hkl) lines with low intensity. The tetragonal lattice parameters of the intercalates were calculated. Both δ-valerolactone and ɛ-caprolactone intercalates are stable in air. The intercalates of lactones with side aliphatic chains are less stable. The CO stretching vibration in IR spectra of the intercalates prepared was shifted to lower wavenumbers in comparison with spectra of the pure guests, indicating that lactones are anchored to the host layers by their carbonyl oxygen. Analogously to the arrangement of γ-butyrolactone, also arrangement of molecules of other lactones in the interlayer space of the host layers was proposed.

  18. Phosphate Barriers for Immobilization of Uranium Plumes

    Energy Technology Data Exchange (ETDEWEB)

    Burns, Peter C.

    2004-12-01

    Uranium contamination of the subsurface remains a persistent problem plaguing remedial design at sites across the U.S. that were involved with production, handling, storage, milling, and reprocessing of uranium for both civilian and defense related purposes. Remediation efforts to date have relied upon excavation, pump-and-treat, or passive remediation barriers (PRB?s) to remove or attenuate uranium mobility. Documented cases convincingly demonstrate that excavation and pump-and-treat methods are ineffective for a number of highly contaminated sites. There is growing concern that use of conventional PRB?s, such as zero-valent iron, may be a temporary solution to a problem that will persist for thousands of years. Alternatives to the standard treatment methods are therefore warranted. The core objective of our research is to demonstrate that a phosphorus amendment strategy will result in a reduction of dissolved uranium to below the proposed drinking water standard. Our hypothesis is that long-chain sodium polyphosphate compounds forestall precipitation of sparingly soluble uranyl phosphate compounds, which is paramount to preventing fouling of wells at the point of injection.

  19. Phosphate Barriers for Immobilization of Uranium Plumes

    Energy Technology Data Exchange (ETDEWEB)

    Icenhower, Jonathan P.; Burns, Peter C.

    2005-06-01

    Uranium contamination of the subsurface remains a persistent problem plaguing remedial design at sites across the U.S. that were involved with production, handling, storage, milling, and reprocessing of uranium for both civilian and defense related purposes. Remediation efforts to date have relied upon excavation, pump-and-treat, or passive remediation barriers (PRB?s) to remove or attenuate uranium mobility. Documented cases convincingly demonstrate that excavation and pump-and-treat methods are ineffective for a number of highly contaminated sites. There is growing concern that use of conventional PRB's, such as zero-valent iron, may be a temporary solution to a problem that will persist for thousands of years. Alternatives to the standard treatment methods are therefore warranted. The core objective of our research is to demonstrate that a phosphorous amendment strategy will result in a reduction of dissolved uranium to below the proposed drinking water standard. Our hypothesis is that long-chain sodium polyphosphate compounds forestall precipitation of sparingly soluble uranyl phosphate compounds, which is paramount to preventing fouling of wells at the point of injection.

  20. Significance of Some Soil Amendments and Phosphate Dissolving Bacteria to Enhance the Availability of Phosphate in Calcareous Soil

    OpenAIRE

    Khalil, Ahmed A.

    2013-01-01

    A field experiment was carried-out on a private farm at the Salah El-Din village, El-Bostan district, Nobaria, El-Behera Governorate, Egypt. The aim of this study was to evaluate the best combination of rock phosphate (RP), sulphur (S), organic manure, and phosphate dissolving bacteria (PDB) inoculation to enhance the availability of phosphorous from rock phosphate and their effects on yield of broad bean plants (cv. Luz doe Otono L.). It was found that either sulphur application or PDB inocu...

  1. A phosphate-starvation-inducible outermembrane protein of Pseudomonas fluorescens Ag1 as an immunological phosphate-starvation marker

    DEFF Research Database (Denmark)

    Leopold, Kristine; Jacobsen, Susanne; Nybroe, Ole

    1997-01-01

    A phosphate-starvation-inducible outer-membrane protein of Pseudomonas fluorescens Ag1, expressed at phosphate concentrations below0.08-0.13 mM, was purified and characterized. The purification method involved separation of outer-membrane proteins by SDS-PAGE andextraction of the protein from...... nitrocellulose or PVDF membranes after electrotransfer of proteins to the membranes. The N-terminal amino acidsequence of the purified protein, called Psi1, did not show homology to any known proteins, and in contrast to the phosphate-specific porin OprP ofP. aeruginosa its mobility in SDS-PAGE was not affected...

  2. Aqueous deposition of calcium phosphates and silicate substituted calcium phosphates on magnesium alloys

    International Nuclear Information System (INIS)

    Attempts were made to deposit homogeneous films of calcium phosphates (CaPs) on two magnesium alloy systems, AZ31 and Mg–4Y, through an aqueous phosphating bath method. The deposition of silicate substituted CaPs by this aqueous method was also explored as silicate substitution is believed to increase the bioactivity of CaPs. The effect of doped and undoped coatings on the in vitro degradation and bioactivity of both alloy systems was studied. FTIR and EDX confirmed the deposition of Ca, P, and Si on both alloys and the coatings appeared to consist primarily biphasic mixtures of hydroxyapatite and β-TCP. These largely inhomogeneous coatings, as observed by SEM, were not shown to have any significant effect on maintaining the physiological pH of the culture medium in comparison to the uncoated samples, as the pH remained approximately in the 8.4–8.7 range. Interestingly, despite similar pH profiles between the coated and uncoated samples, CaP coatings affected the degradation of both alloys. These doped and undoped calcium phosphate coatings were observed to decrease the degradation of AZ31 whereas they increased the degradation of Mg–4Y. In vitro studies on cell attachment using MC3T3-E1 mouse osteoblasts showed that between the uncoated alloys, Mg–4Y appeared to be the more biocompatible of the two. Silicate substituted CaP coatings were observed to increase the cell attachment on AZ31 compared to bare and undoped CaPs coated samples, but did not have as great of an effect on increasing cell attachment on Mg–4Y.

  3. Iron-phosphate-based chemically bonded phosphate ceramics for mixed waste stabilization

    International Nuclear Information System (INIS)

    In an effort to develop chemically bonded phosphate ceramics for mixed waste stabilization, a collaborative project to develop iron-phosphate based ceramics has been initiated between Argonne National Laboratory and the V. G. Khlopin Radium Institute in St. Petersburg, Russia. The starter powders are oxides of iron that are generated as inexpensive byproduct materials in the iron and steel industry. They contain iron oxides as a mixture of magnetite (Fe3O4) and haematite (Fe2O3). In this initial phase of this project, both of these compounds were investigated independently. Each was reacted with phosphoric acid solution to form iron phosphate ceramics. In the case of magnetite, the reaction was rapid. Adding ash as the waste component containing hazardous contaminants resulted in a dense and hard ceramic rich in glassy phase. On the other hand, the reaction of phosphoric acid solution with a mixture of haematite and ash waste contaminated with cesium and americium was too slow. Samples had to be molded under pressure. They were cured for 2-3 weeks and then hardened by heating at 350 degrees C for 3 h. The resulting ceramics in both cases were subjected to physical tests for measurement of density, open porosity, compression strength, phase analyses using X-ray diffraction and differential thermal analysis, and leaching tests using toxicity characteristic leaching procedure (TCLP) and ANS 16.1 with 7 days of leaching. Using the preliminary information obtained from these tests, we evaluated these materials for stabilization of Department of Energy's mixed waste streams

  4. Analysis of serum phosphate control and phosphate binder utilization in incident hemodialysis patients

    OpenAIRE

    Gibson, Fernando

    2014-01-01

    Kimberly F Farrand,1 J Brian Copley,1 Jamie Heise,1 Moshe Fridman,2 Michael S Keith,1 Lynne Poole3 1Shire, Wayne, PA, USA; 2AMF Consulting, Los Angeles, CA, USA; 3Shire, Basingstoke, UK Abstract: The purpose of this study was to conduct a retrospective analysis of serum phosphate level variability in patients new to hemodialysis (HD) and to identify patient characteristics associated with this variability. The medical records of 47,742 incident HD patients attending US outpatient dialysis ce...

  5. Hierarchical bismuth phosphate microspheres with high photocatalytic performance

    Energy Technology Data Exchange (ETDEWEB)

    Pei, Lizhai; Wei, Tian; Lin, Nan; Yu, Haiyun [Anhui University of Technology, Ma' anshan (China). Key Laboratory of Materials Science and Processing of Anhui Province

    2016-05-15

    Hierarchical bismuth phosphate microspheres have been prepared by a simple hydrothermal process with polyvinyl pyrrolidone. Scanning electron microscopy observations show that the hierarchical bismuth phosphate microspheres consist of nanosheets with a thickness of about 30 nm. The diameter of the microspheres is about 1 - 3 μm. X-ray diffraction analysis shows that the microspheres are comprised of triclinic Bi{sub 23}P{sub 4}O{sub 44.5} phase. The formation of the hierarchical microspheres depends on polyvinyl pyrrolidone concentration, hydrothermal temperature and reaction time. Gentian violet acts as the pollutant model for investigating the photocatalytic activity of the hierarchical bismuth phosphate microspheres under ultraviolet-visible light irradiation. Irradiation time, dosage of the hierarchical microspheres and initial gentian violet concentration on the photocatalytic efficiency are also discussed. The hierarchical bismuth phosphate microspheres show good photocatalytic performance for gentian violet removal in aqueous solution.

  6. Phosphate bonded ceramics as candidate final-waste-form materials

    International Nuclear Information System (INIS)

    Room-temperature setting phosphate-bonded ceramics were studied as candidate materials for stabilization of DOE low-level problem mixed wastes which cannot be treated by other established stabilization techniques. Phosphates of Mg, Mg-Na, Al and Zr were studied to stabilize ash surrogate waste containing RCRA metals as nitrates and RCRA organics. We show that for a typical loading of 35 wt.% of the ash waste, the phosphate ceramics pass the TCLP test. The waste forms have high compression strength exceeding ASTM recommendations for final waste forms. Detailed X-ray diffraction studies and differential thermal analyses of the waste forms show evidence of chemical reaction of the waste with phosphoric acid and the host matrix. The SEM studies show evidence of physical bonding. The excellent performance in the leaching tests is attributed to a chemical solidification and physical as well as chemical bonding of ash wastes in these phosphate ceramics

  7. Investigation of Wear Coefficient of Manganese Phosphate Coated Tool Steel

    Directory of Open Access Journals (Sweden)

    S. Ilaiyavel

    2013-03-01

    Full Text Available In recent years the properties of the coating in terms of wear resistance is of paramount importance in order to prevent the formation of severe damages. In this study, Wear coefficient of uncoated, Manganese Phosphate coated, Manganese Phosphate coated with oil lubricant, Heat treated Manganese Phosphate coated with oil lubricant on AISI D2 steels was investigated using Archard’s equation. The wear tests were performed in a pin on disk apparatus as per ASTM G-99 Standard. The volumetric wear loss and wear coefficient were evaluated through pin on disc test using a sliding velocity of 3.0 m/s under normal load of 40 N and controlled condition of temperature and humidity. Based on the results of the wear test, the Heat treated Manganese Phosphate with oil lubricant exhibited the lowest average wear coefficient and the lowest wear loss under 40 N load.

  8. Biomineralization of uraninite and uranyl phosphate controlled by organic acids

    International Nuclear Information System (INIS)

    Biomineralization of uraninite (UO2) and uranyl phosphate minerals are both able to decrease the mobility of uranium in the environment. We examined biomineralization of UO2 and uranyl phosphate by Shewanella putrefaciens in the basic medium containing lactate as an electron donor, β- glycerolphosphate as a phosphorous source, and uranyl nitrate in the absence and presence of weak or strong complexing organic acids (WCOA or SCOA) under an anaerobic condition. In the basic medium, only biomineralization of UO2 was observed because of rapid reduction of U(VI). Biomineralization of UO2 and uranyl phosphate occurred in the media with WCOA, however the no biomineralization was occurred in the presence of SCOA. It is thought that formation of stable U(VI)-, and U(IV)- organic complexes prevents the biomineralization. These finding suggest that coexisting organic acids control the biomineralization of UO2 and uranyl phosphate minerals by microorganisms. (author)

  9. Determination of the relative efficiencies of phosphatic fertilisers

    International Nuclear Information System (INIS)

    A pot experiment was conducted to determine the relative efficiency of phosphate of three sources (triple superphosphate, dicalcium phosphate, and rock phosphate) applied in thee levels (0,200 and 40 ppm) to loamy and clay loam soils. Solution of KH2PO4 contained 10 ppm P labelled with 32P added to all treatments. The plants were grown in growth room for 63 days then harvested. The plant materials were oven dried, grounded and wet digested for chemical and radiochemical analysis. The data indicated P fertilizers, P rates and soil textures caused significant effects on dry matter yield, P-content, total-P, fertiliser yield, % derived from soil fertiliser, and A-value at 0.05 probability level. Triple superphosphate was found to surpass the other P sources. Rock phosphate showed little effect on barley production

  10. Effect of Phosphate on Zinc Transport in Lou Soil

    Institute of Scientific and Technical Information of China (English)

    LUJIALONG; DONGLINGIAO; 等

    1998-01-01

    A study on the transport characteristics of zinc in lou soil with phosphate at different concentrations was carried out by the method of step input.The effects of phosphate and temperature on zinc transport were studied through analysing the diffusion-dipsersion coefficients(D) and the retardation factor(R) obtained by the program CXTFIT.The results showed that D decreased and R increased with increasig concentration of phosphate so that iv was difficult for zinc to break through the soil column,and zinc stopped to break through the column at high temperature.One order equation,double constant equation and the Elovich equation were all suitable for the escription of zinc dynamics.Effects of phosphate and temperature on zinc transport were further confirmed by the analysis on pseudo-thermodynamic parameters of zinc transport.

  11. Studies of natural radioactivity of some Egyptian rock phosphates

    International Nuclear Information System (INIS)

    226Ra, 235U, 232Th and 40K activity concentrations (Bq/kg) in some Egyptian phosphate samples have been measured using HPGe gamma spectrometer. Also their radium equivalent activities were calculated and discussed. (author)

  12. 3D printing of octacalcium phosphate bone substitutes

    Directory of Open Access Journals (Sweden)

    Vladimir S. Komlev

    2015-06-01

    Full Text Available Biocompatible calcium phosphate ceramic grafts are able of supporting new bone formation in appropriate environment. The major limitation of these materials usage for medical implants is the absence of accessible methods for their patient-specific fabrication. 3D printing methodology is an excellent approach to overcome the limitation supporting effective and fast fabrication of individual complex bone substitutes. Here we proposed a relatively simple route for 3D printing of octacalcium phosphates in complexly shaped structures by the combination of inkjet printing with post-treatment methodology. The printed octacalcium phosphate blocks were further implanted in the developed cranial bone defect followed by histological evaluation. The obtained result confirmed the potential of the developed octacalcium phosphates bone substitutes, which allowed 2.5-time reducing of defect’s diameter at 6.5 months in a region where native bone repair is extremely inefficient.

  13. Phosphate overload accelerates vascular aging in uremic patients

    Directory of Open Access Journals (Sweden)

    Diego Brancaccio

    2006-05-01

    Full Text Available Vascular calcification is a very common event in patients affected by diabetes and chronic kidney disease (CKD. Recently, it has been well documented that abnormalities in mineral and bone metabolism in CKD patients are associated with increased morbidity and mortality. Elevated serum phosphate and calcium-phosphate product levels play an important role in the pathogenesis of vascular mineralization in uremic patients and also appear to be associated with increased cardiovascular mortality. Together with classical passive precipitation of calciumphosphate in soft tissues, during the last decade it has been demonstrated that inorganic phosphate may cause extraskeletal calcification directly through a real “ossification” of the tunica media in the vasculature of CKD patients. Therefore, control of phosphate retention is now an even more crucial target of treatment in patients affected by chronic kidney disease.

  14. Investigation of the benzotriazole as addictive for carbon steel phosphating

    International Nuclear Information System (INIS)

    This work studied the viability of substitution of sodium nitrite (NaNO2) for benzotriazole (BTAH) in the zinc phosphate bath (PZn+NaNO2) for phosphating of carbon steel (SAE 1010). The characterization of the samples was carried out by Scanning Electron Microscopy, Optical Microscopy and X-ray diffraction. The chemical composition was evaluated by Energy Dispersive Spectroscopy. The corrosion behavior of the samples was investigated by Open Circuit Potential, Electrochemical Impedance Spectroscopy and Anodic Potentiodynamic Polarization Curves in a 0.5 mol L-1 NaCl electrolyte. The experimental results showed that the phosphate layer obtained in the solution with benzotriazole (PZn+BTAH) presented better corrosion resistance properties than that obtained in sodium nitrite. The results demonstrated that the sodium nitrite NaNO2 can be replaced by benzotriazole (BTAH) in zinc phosphate baths. (author)

  15. Calculation of dynamics of silver sorption by zirconium phosphate

    International Nuclear Information System (INIS)

    The experimental and calculation data on kinetics and dynamics of silver ions sorption by zirconium phosphate are considered in present article. The evaluation of sorption process in dynamic conditions is carried out.

  16. Genetics Home Reference: carbamoyl phosphate synthetase I deficiency

    Science.gov (United States)

    Skip to main content Your Guide to Understanding Genetic Conditions Enable Javascript for addthis links to activate. ... Conditions Genes Chromosomes & mtDNA Resources Help Me Understand Genetics Home Health Conditions carbamoyl phosphate synthetase I deficiency ...

  17. Characterization of cement calcium phosphate for use dental

    International Nuclear Information System (INIS)

    Calcium phosphates are interesting biological and medical attention due to its occurrence in different animal species and humans. Ceramics based on calcium phosphate in the form of implants or porous particulate materials, have proven to be suitable replacements for bone tissue when they are only subjected to small mechanical stresses. Was obtained research laboratory DEMA/UFCG a calcium phosphate phase. The goal is to characterize the material by X-ray diffraction (XRD) in order to analyze what the phases and infrared spectroscopy (FTIR) to identify the absorption bands of the bonding characteristic. Was identified by XRD phase present in the sample is hydroxyapatite Ca/P 1.67. In infrared spectroscopy has absorption bands characteristic of the phosphate group at 1032 cm1 region. (author)

  18. The Antimicrobial Action of Silver Halides in Calcium Phosphate

    OpenAIRE

    Kalniņa, D; Gross, K; Onufrijevs, P.; Daukšta, E; Nikolajeva, V; Stankeviciute, Z; Kareiva, A.

    2015-01-01

    Silver halides represent a yet unexplored avenue for imparting antimicrobial activity to calcium phosphates. Negtively charged silver halide colloids (AgI, AgBr and AgCl) were added to synthesized amorphous calcium phosphate. Concurrent melting of silver halides and crystallization to carbonated apatite at 700 oC increased the silver halide surface area available to bacteria and formed a lower solubility apatite. The effect of the matrix solubility on antimicrobial response could ...

  19. A review paper on biomimetic calcium phosphate coatings

    OpenAIRE

    Lin, X.; De Groot,, P.A.J.; Wang, D.; Hu, Q; Wismeijer, D.; Liu, Y

    2015-01-01

    Biomimetic calcium phosphate coatings have been developed for bone regeneration and repair because of their biocompatibility, osteoconductivity, and easy preparation. They can be rendered osteoinductive by incorporating an osteogenic agent, such as bone morphogenetic protein 2 (BMP-2), into the crystalline lattice work in physiological situations. The biomimetic calcium phosphate coating enables a controlled, slow and local release of BMP-2 when it undergoes cell mediated coating degradation ...

  20. Calcium phosphate mineralization is widely applied in crustacean mandibles

    OpenAIRE

    Shmuel Bentov; Aflalo, Eliahu D.; Jenny Tynyakov; Lilah Glazer; Amir Sagi

    2016-01-01

    Crustaceans, like most mineralized invertebrates, adopted calcium carbonate mineralization for bulk skeleton reinforcement. Here, we show that a major part of the crustacean class Malacostraca (which includes lobsters, crayfishes, prawns and shrimps) shifted toward the formation of calcium phosphate as the main mineral at specified locations of the mandibular teeth. In these structures, calcium phosphate is not merely co-precipitated with the bulk calcium carbonate but rather creates speciali...

  1. Study of electrochemical phosphate conversion coating of metallic surfaces

    International Nuclear Information System (INIS)

    After an overview on phosphate conversion coating processes, on models of iron electrochemical dissolution, on the passivation phenomenon, and on the phosphate conversion coating treatment, this research thesis reports a detailed study of this last process. The author presents the experimental method, reports the study of this process and of passivation under constant polarization. He reports the use of various techniques and conditions: chrono-amperometry, chrono-potentiometry, cyclic volt-amperometry

  2. Phosphate vibrations probe local electric fields and hydration in biomolecules

    OpenAIRE

    Nicholas M Levinson; Bolte, Erin E.; Miller, Carrie S.; Corcelli, Steven A.; Boxer, Steven G.

    2011-01-01

    The role of electric fields in important biological processes like binding and catalysis has been studied almost exclusively by computational methods. Experimental measurements of the local electric field in macromolecules are possible using suitably calibrated vibrational probes. Here we demonstrate that the vibrational transitions of phosphate groups are highly sensitive to an electric field and quantify that sensitivity, allowing local electric field measurements to be made in phosphate-co...

  3. Phosphate vibrations probe local electric fields and hydration in biomolecules

    Science.gov (United States)

    Levinson, Nicholas M.; Bolte, Erin E.; Miller, Carrie S.

    2011-01-01

    The role of electric fields in important biological processes like binding and catalysis has been studied almost exclusively by computational methods. Experimental measurements of the local electric field in macromolecules are possible using suitably calibrated vibrational probes. Here we demonstrate that the vibrational transitions of phosphate groups are highly sensitive to an electric field and quantify that sensitivity, allowing local electric field measurements to be made in phosphate-containing biological systems without chemical modification. PMID:21809829

  4. The recovery of uranium and the lanthanides from phosphate rock

    International Nuclear Information System (INIS)

    A process is proposed for the treatment of phosphate rock for the recovery of uranium and the lanthanides. The process is based on the use of nitric acid for leaching the rock, the use of common reagents for the recovery of fluorine and the removal of radium, and the use of organic solvent for the recovery of uranium and the lanthanides. The process assures the production of phosphatic fertilizers without polluting the environment with radioactive material

  5. A yeast expression system for human galactose-1-phosphate uridylyltransferase.

    OpenAIRE

    Fridovich-Keil, J L; Jinks-Robertson, S

    1993-01-01

    Galactose-1-phosphate uridylyltransferase (GALT) (UTP: alpha-D-hexose-1-phosphate uridylyltransferase, EC 2.7.7.10) is an essential enzyme of the Leloir pathway of galactose metabolism. Mutations in human GALT are associated with the potentially lethal disorder galactosemia, which affects 1 in 30,000-60,000 live-born infants. Although a number of base substitutions have been identified in the GALT alleles of galactosemia patients, the detailed biochemical impact of these mutations on GALT enz...

  6. Mars-relevant phosphate minerals and implications for Martian habitability

    Science.gov (United States)

    Adcock, Christopher T.

    This dissertation is comprised of three studies focused on martian phosphate availability, with an introductory chapter introducing and linking the three studies. Chapter two is on the subject of merrillite synthesis. Merrillite is an extraterrestrial Ca-phosphate mineral similar to the mineral whitlockite and is found as a dominant primary phosphate mineral in martian meteorites. The chapter includes methods of whitlockite and merrillite synthesis as well as a detailed characterization of the produced minerals and a mechanism by which charge balance can be maintained when merrillite is synthesized through dehydrogenation of whitlockite. Chapter three presents the results of kinetic and thermodynamic studies on the Mars-relevant minerals chlorapatite and merrillite, as well as the more terrestrially-relevant minerals whitlockite and fluorapatite. The results of these studies indicate that the dominant primary Ca-phosphate minerals on Mars possess higher solubilities that could lead to more than twice the phosphate concentration in solution. Dissolution rates for the Mars-relevant minerals derived in the study, when combined with the higher martian phosphorus abundance, could result in phosphate release rates of up to 45x faster for a given set of aqueous conditions on Mars when compared to Earth. The implications of the results for past or present martian habitability are discussed. In Chapter four, reactive transport modeling was applied to investigate the transport and mobility of phosphate under martian conditions. The kinetic and thermodynamic data derived in Chapter three were combined with Mars mission data, results from an investigation of Mars analog basalts at Craters of the Moon National Monument in Idaho, and previously published data to inform a reactive transport code and model dissolution profiles measured by Mars Exploration Rover (MER) Spirit in Wishstone class rocks. The modeling results suggest phosphate release into near-neutral waters occurred

  7. Phosphate binding therapy in dialysis patients: focus on lanthanum carbonate

    Directory of Open Access Journals (Sweden)

    Ismail A Mohammed

    2008-11-01

    Full Text Available Ismail A Mohammed, Alastair J HutchisonManchester Institute of Nephrology and Transplantation, Manchester Royal Infirmary, Oxford Road, Manchester, UKAbstract: Hyperphosphatemia is an inevitable consequence of end stage chronic kidney disease and is present in the majority of dialysis patients. Recent observational data has associated hyperphosphatemia with increased cardiovascular mortality among dialysis patients. Dietary restriction of phosphate and current dialysis prescription practices are not enough to maintain serum phosphate levels within the recommended range so that the majority of dialysis patients require oral phosphate binders. Unfortunately, conventional phosphate binders are not reliably effective and are associated with a range of limitations and side effects. Aluminium-containing agents are highly efficient but no longer widely used because of well established and proven toxicity. Calcium based salts are inexpensive, effective and most widely used but there is now concern about their association with hypercalcemia and vascular calcification. Sevelamer hydrochloride is associated with fewer adverse effects, but a large pill burden and high cost are limiting factors to its wider use. In addition, the efficacy of sevelamer as a monotherapy in lowering phosphate to target levels in severe hyperphosphatemia remains debatable. Lanthanum carbonate is a promising new non-aluminium, calcium-free phosphate binder. Preclinical and clinical studies have demonstrated a good safety profile, and it appears well tolerated and effective in reducing phosphate levels in dialysis patients. Its identified adverse events are apparently mild to moderate in severity and mostly GI related. It appears to be effective as a monotherapy, with a reduced pill burden, but like sevelamer, it is significantly more expensive than calcium-based binders. Data on its safety profile over 6 years of treatment are now available.Keywords: hyperphosphatemia, lanthanum

  8. Phosphate recovery using calcium zeolite in ultrafiltration pilot plant

    OpenAIRE

    La Rotonda Ferrer, Pablo

    2015-01-01

    One of the most important ecological problems is the eutrophication, this process consist in the uncontrolled growing of algae and phytoplankton, which can destroy entire aquatic ecosystems. The reason of this process is the excess of nutrients, as for example, phosphate coming from human activities. This project focus on the study of synthetic zeolites capacity to absorb phosphate from wastewater. Zeolites are porous minerals of the alumina-silicates family with high capacity ...

  9. Amorphous calcium phosphate composites with improved mechanical properties

    OpenAIRE

    O’Donnell, J.N.R.; Antonucci, J.M.; Skrtic, D.

    2006-01-01

    Hybridized zirconium amorphous calcium phosphate (ACP)-filled methacrylate composites make good calcium and phosphate releasing materials for anti-demineralizing/remineralizing applications with low mechanical demands. The objective of this study was to assess the effect of the particle size of the filler on the mechanical properties of these composites. Photo-curable resins were formulated from ethoxylated bisphenol A dimethacrylate, triethylene glycol dimethacrylate, 2-hydroxyethyl methacry...

  10. Calcium phosphate-based ceramic and composite materials for medicine

    International Nuclear Information System (INIS)

    The topical problems in chemistry and technology of materials based on calcium phosphates aimed at both the replacement of damaged bone tissue and its regeneration are discussed. Specific features of the synthesis of nanocrystalline powders and the fabrication of ceramic implants are described. Advances in the development of porous scaffolds from resorbable and osteoconductive calcium phosphates and of hybrid composites that form the basis of bone tissue engineering are considered.

  11. Interplay between genetic regulation of phosphate homeostasis and bacterial virulence

    OpenAIRE

    Chekabab, Samuel Mohammed; Harel, Josée; Dozois, Charles M.

    2014-01-01

    Bacterial pathogens, including those of humans, animals, and plants, encounter phosphate (Pi)-limiting or Pi-rich environments in the host, depending on the site of infection. The environmental Pi-concentration results in modulation of expression of the Pho regulon that allows bacteria to regulate phosphate assimilation pathways accordingly. In many cases, modulation of Pho regulon expression also results in concomitant changes in virulence phenotypes. Under Pi-limiting conditions, bacteria u...

  12. VIBRATIONAL RELAXATION ON HYDROGEN BONDING IN DINUCLEOSIDE PHOSPHATE

    OpenAIRE

    Yoshii, Giichi

    1983-01-01

    The specific interactions between bases, which depend on the dinucleoside phosphate conformations, were studied in terms of the vibrational dynamics of hydrogen-bonding. The hydrogen-bond stretching vibrations of the nucleotide complexes and dinucleoside phosphates were observed in the polycrystalline state by the Raman spectroscopy. The vibrational dynamics were investigated by measuring the line broadenings of hydrogen-bonding vibration observed in near 100cm^. The half band-widths of vibra...

  13. Active site geometry of glucose-1-phosphate uridylyltransferase

    OpenAIRE

    Thoden, James B.; Holden, Hazel M.

    2007-01-01

    Glucose-1-phosphate uridylyltransferase, or UGPase, catalyzes the production of UDP-glucose from glucose-1-phosphate and UTP. Because of the biological role of UDP-glucose in glycogen synthesis and in the formation of glycolipids, glycoproteins, and proteoglycans, the enzyme is widespread in nature. Recently this laboratory reported the three-dimensional structure of UGPase from Escherichia coli. While the initial X-ray analysis revealed the overall fold of the enzyme, details concerning its ...

  14. Study of Phosphating Process for Artillery Pipes Subjected to Mechanical Self-shrinkage with Mandrel

    Directory of Open Access Journals (Sweden)

    Ioan Ciorba

    2013-05-01

    Full Text Available This paper present the results of a study that was made to establish the optimal parameters of phosphating process for artillery pipes. The optimal parameters that were determined after analysis are: the temperature of phosphating solution respectively the holding time in the phosphate bathroom to obtain a maximum thickness of phosphate layer.

  15. Chemoenzymatic synthesis of 1-deaza-pyridoxal 5’-phosphate

    OpenAIRE

    Griswold, Wait R.; Toney, Michael D.

    2010-01-01

    The first synthesis of 1-deaza-pyridoxal 5’-phosphate (2-formyl-3-hydroxy-4-methylbenzyl phosphate) is described. The chemoenzymatic approach described here is a reliable route to this important isosteric pyridoxal phosphate analogue. This work enables elucidation of the role of the pyridine nitrogen in pyridoxal 5’-phosphate dependent enzymes.

  16. Effect of Phosphate Concentration on Production of Tetrodotoxin by Alteromonas tetraodonis

    OpenAIRE

    Gallacher, Susan; Birkbeck, T.H.

    1993-01-01

    Tetrodotoxin production by Alteromonas tetraodonis occurred during the stationary phase of growth and was regulated by phosphate concentration; toxin production was repressed if phosphate was added at the onset of stationary phase and was over 100-fold greater in phosphate-limited cultures than in cultures in which phosphate was not limiting.

  17. Phosphate availability in the soil-root system: integration of oxide surface chemistry, transport and uptake.

    NARCIS (Netherlands)

    Geelhoed, J.S.

    1998-01-01

    A study is presented on the adsorption of phosphate on goethite, the interaction of phosphate with other adsorbing ions at the goethite surface, and the resulting availability of phosphate to plants. The plant-availability of sorbed phosphate was determined from phosphorus uptake of plants growing o

  18. International symposium on cellular and molecular biology of phosphate and phosphorylated compounds in microorganisms: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-12-31

    This report contains the abstracts of papers presented at the conference. Attention is focused on the following topics: regulation of phosphate metabolism in bacteria; structure-function of alkaline phosphatase; regulation of phosphate metabolism in yeast; transport of phosphate and phosphorylated compounds; and phosphate regulation in pathogenesis and secondary metabolism.

  19. Immobilization of fission products in phosphate ceramic waste forms

    International Nuclear Information System (INIS)

    Chemically bonded phosphate ceramics (CBPCs) have several advantages that make them ideal candidates for containing radioactive and hazardous wastes. In general, phosphates have high solid-solution capacities for incorporating radionuclides, as evidenced by several phosphates (e.g., monazites and apatites) that are natural analogs of radioactive and rare-earth elements. The phosphates have high radiation stability, are refractory, and will not degrade in the presence of internal heating by fission products. Dense and hard CBPCs can be fabricated inexpensively and at low temperature by acid-base reactions between an inorganic oxide/hydroxide powder and either phosphoric acid or an acid-phosphate solution. The resulting phosphates are extremely insoluble in aqueous media and have excellent long-term durability. CBPCs offer the dual stabilization mechanisms of chemical fixation and physical encapsulation, resulting in superior waste forms. The goal of this task is develop and demonstrate the feasibility of CBPCs for S/S of wastes containing fission products. The focus of this work is to develop a low-temperature CBPC immobilization system for eluted 99Tc wastes from sorption processes

  20. Synthesis and Characterization of Metal Phosphates for Photocatalytic Applications

    KAUST Repository

    Al-Sabban, Bedour

    2012-07-01

    Solar energy is the most abundant efficient and important source of renewable energy. The objective of this study is to develop highly efficient visible light responsive photocatalysts for overall water splitting. This is done by using silver or copper containing materials. Phosphate compounds have caught much attention due to their rigid structure, thermal stability and resistance to chemical attacks. Solid phosphates can be prepared by direct solid-state reaction between metal cations and phosphate anions at high temperatures. Double metal phosphates of the Nasion-type structure had shown further technological importance. It has been reported that well-crystallized double metal phosphate particles have excellent ordering and cationic conduction channels in the Nasicon framework. In this study, several Nasion-type structured materials have been synthesized by solid-state method (e.g. CuTi2(PO4)3 and AgTi2(PO4)3) heated up under different temperatures (400–1100C) in N2 or air atmosphere. These materials were characterized by XRD, SEM, DR-UV-Vis spectroscopy and tested for photocatalytic applications. A new method for direct synthesis of photoelectrode on Ti Plate had been demonstrated. Further investigations on controlling the size and morphology for better performance of single and double metal phosphates will be done.

  1. Immobilization of fission products in phosphate ceramic waste forms

    Energy Technology Data Exchange (ETDEWEB)

    Singh, D.; Wagh, A. [Argonne National Lab., IL (United States)

    1997-10-01

    Chemically bonded phosphate ceramics (CBPCs) have several advantages that make them ideal candidates for containing radioactive and hazardous wastes. In general, phosphates have high solid-solution capacities for incorporating radionuclides, as evidenced by several phosphates (e.g., monazites and apatites) that are natural analogs of radioactive and rare-earth elements. The phosphates have high radiation stability, are refractory, and will not degrade in the presence of internal heating by fission products. Dense and hard CBPCs can be fabricated inexpensively and at low temperature by acid-base reactions between an inorganic oxide/hydroxide powder and either phosphoric acid or an acid-phosphate solution. The resulting phosphates are extremely insoluble in aqueous media and have excellent long-term durability. CBPCs offer the dual stabilization mechanisms of chemical fixation and physical encapsulation, resulting in superior waste forms. The goal of this task is develop and demonstrate the feasibility of CBPCs for S/S of wastes containing fission products. The focus of this work is to develop a low-temperature CBPC immobilization system for eluted {sup 99}Tc wastes from sorption processes.

  2. Effect of phosphate supplementation on oxygen delivery at high altitude

    Science.gov (United States)

    Jain, S. C.; Singh, M. V.; Rawal, S. B.; Sharma, V. M.; Divekar, H. M.; Tyagi, A. K.; Panwar, M. R.; Swamy, Y. V.

    1987-09-01

    In the present communication, effect of low doses of phosphate supplementation on short-term high altitude adaptation has been examined. Studies were carried out in 36 healthy, male, sea-level residents divided in a double blind fashion into drug and placebo treated groups. 3.2 mmol of phosphate were given orally to each subject of the drug treated group once a day for 4 days on arrival at an altitude of 3,500 m. Sequential studies were done in the subjects in both groups on the 3rd, 7th, 14th and 21st day of their altitude stay. Haemoglobin, haematocrit, erythrocyte and reticulocyte counts increased to the similar extent in both groups. Blood pH, pO2 and adenosine tri-phosphate (ATP) did not differ between the two groups. On 3rd day of the altitude stay, inorganic phosphate and 2,3-diphosphoglycerate (2,3 DPG) levels in the drug treated group increased significantly as compared to the placebo group. No significant difference in inorganic phosphate and 2,3 DPG was observed later on in the two groups. Psychological and clinical tests also indicated that the drug treated subjects felt better as compared to the placebo treated subjects. The present study suggests that low doses of phosphate increases circulating 2,3-DPG concentration which in turn brings about beneficial effect towards short term high altitude adaptation.

  3. Removal of phosphate by mesoporous ZrO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Liu Honglei; Sun Xiaofei; Yin Chengqing [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 10085 (China); Hu Chun [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 10085 (China)], E-mail: huchun@rcees.ac.cn

    2008-03-01

    A type of mesoporous ZrO{sub 2} was synthesized and its phosphate removal potential was investigated in this study. The adsorption isotherm, pH effect, ionic strength effect and desorption were examined in batch experiments. The adsorption data fitted well to the Langmuir model with which the maximum P adsorption capacity was estimated to be 29.71 mg P/g. The amount of phosphate adsorbed increased rapidly in the first 5 h and slowly towards the end of the run, suggesting the possible monolayer coverage of phosphate ions on the surface of the adsorbent. The phosphate adsorption tended to increase with a decrease of pH and an increase of ionic strength. A phosphate desorbability of approximately 60% was observed with 0.5 M NaOH, which indicated a relatively strong bonding between the adsorbed PO{sub 4}{sup 3-} and the sorptive sites on the surface of the adsorbent. The immobilization of phosphate probably occurs by the mechanisms of ion exchange and physicochemical attraction. Due to its high adsorption capacity, this type of Zirconium oxide has the potential for application to control phosphorus pollution.

  4. Sphingosine-1 phosphate prevents ethanol-induced corneal epithelial apoptosis

    Directory of Open Access Journals (Sweden)

    Pierre Fournie

    2012-01-01

    Full Text Available Background: Apoptosis is a programmed cell death in multicellular organisms, found in a wide variety of conditions, including inflammatory process, everywhere in the body, including the cornea and conjunctiva. Aim: To evaluate the effect of a new topical formulation of sphingosine-1 phosphate on preventing apoptosis of the corneal epithelium. Setting: Medical University. Materials and Methods: We tested several formulations suitable for topical application. Twenty-five rabbits were distributed among five groups. Group 1 comprised the controls. In Group 2, 20% ethanol was applied topically for 20 seconds; in Group 3, 50 μM topical sphingosine-1 phosphate was applied 2 hours prior to 20% ethanol application. In Group 4, 200 μM topical sphingosine-1 phosphate was applied 2 hours before the 20% ethanol application. In Group 5, only 200 μM topical sphingosine-1 phosphate was applied. Apoptosis was evaluated using the terminal deoxynucleotidyl transferase biotin-dUTP Nick End Labeling (TUNEL assay. Pairwise comparisons were performed using t-tests with Scheffe′s correction. Data were analyzed using STATA 9.0 statistical software. Results: A suspension of sphingosine-1 phosphate in the presence of Montanox 80 was stable and could be formulated without sonication. Epithelial apoptosis was detected only in Groups 2 and 3. Conclusion: Sphingosine-1 phosphate can prevent ethanol-induced apoptosis in the corneal epithelium of rabbits.

  5. Phosphate binders in chronic kidney disease: a systematic review of recent data.

    Science.gov (United States)

    Floege, Jürgen

    2016-06-01

    Hyperphosphatemia is common in chronic kidney disease (CKD) and is treated by dietary measures, dialysis techniques and/or phosphate binders. For the present review PubMed was searched for new publications on phosphate binders appearing between January 2010 and October 2015. This review summarizes the latest information on non-pharmacological measures and their problems in lowering phosphate in CKD patients, effects of phosphate binders on morbidity and mortality, adherence to phosphate binder therapy as well as new information on specific aspects of the various phosphate binders on the market: calcium acetate, calcium carbonate, magnesium-containing phosphate binders, polymeric phosphate binders (sevelamer, bixalomer, colestilan), lanthanum carbonate, ferric citrate, sucroferric oxyhydroxide, aluminum-containing phosphate binders, and new compounds in development. The review also briefly covers the emerging field of drugs targeting intestinal phosphate transporters. PMID:26800972

  6. Overexpression, crystallization and preliminary X-ray analysis of xylulose-5-phosphate/fructose-6-phosphate phosphoketolase from Bifidobacterium breve

    International Nuclear Information System (INIS)

    Xylulose-5-phosphate/fructose-6-phosphate phosphoketolase from B. breve was overexpressed and crystallized. The crystals belonged to the tetragonal space group I422 and diffracted to beyond 1.7 Å resolution. The xylulose-5-phosphate/fructose-6-phosphate phosphoketolase gene from Bifidobacterium breve was cloned and overexpressed in Escherichia coli. The enzyme was purified to homogeneity and crystallized by the sitting-drop vapour-diffusion method. Crystals were obtained at 293 K using 0.05 mM thiamine diphosphate, 0.25 mM MgCl2, 24%(w/v) PEG 6000 and 0.1 M Bicine pH 9.0. The crystals belonged to the tetragonal space group I422, with unit-cell parameters a = b = 174.8, c = 163.8 Å, and diffracted to beyond 1.7 Å resolution

  7. Use of osmolytes during solubilization and reconstitution of phosphate: sugar phosphate antiport from bacteria

    International Nuclear Information System (INIS)

    Phosphate:2-deoxyglucose 6-phosphate (Pi:2DG6P) antiport was extracted from Streptococcus lactis or Staphylococcus aureus with 1.1% octylglucoside in the presence of 0.37% E. coli lipid and reconstituted by detergent dilution. Because previous work suggested inactivation at an early stage, the authors introduced protein stabilants during solubilization. When 20% glycerol was used, proteoliposomes showed a 20-fold increase in 32Pi transport. This enhanced recovery required phospholipid plus glycerol, and was found only when both were added together with the detergent. Glycerol protection yielded proteoliposomes in which antiporters retained their normal kinetic properties, and Pi exchange by the streptococcal example gave a maximal rate (200-400 nmol/min per mg protein) and a turnover number (30-50/s) which suggested that inactivation had been avoided. Further study showed that 20% glycerol could be replaced by equally high concentrations of compounds classified as osmolytes polyols (erythritol, xylitol, sorbitol), sugars (glucose, trehalose) and certain amino acids (glycine, proline, but not valine). The authors suggest that osmolytes may be used to fully stabilize chemiosmotic transporters during reconstitution

  8. Recovery of uranium from 30 vol % tributyl phosphate solvents containing dibutyl phosphate

    International Nuclear Information System (INIS)

    A number of solid sorbents were tested for the removal of uranium and dibutyl phosphate (DBP) from 30% tributyl phosphate (TBP) solvent. The desired clean uranium product can be obtained either by removing the DBP, leaving the uranium in the solvent for subsequent stripping, or by removing the uranium, leaving the DBP in the solvent for subsequent treatment. The tests performed show that it is relatively easy to preferentially remove uranium from solvents containing uranium and DBP, but quite difficult to remove DBP preferentially. The current methods could be used by removing the uranium (as by a cation exchange resin) and then using either an anion exchange resin in the hydroxyl form or a conventional treatment with a basic solution to remove the DBP. Treatment of a solvent with a cation exchange resin could be useful for recovery of valuable metals from solvents containing DBP and might be used to remove cations before scrubbing a solvent with a basic solution to minimize emulsion formation. 6 refs., 9 figs

  9. Use of osmolytes during solubilization and reconstitution of phosphate: sugar phosphate antiport from bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Ambudkar, S.V.; Sonna, L.A.; Maloney, P.C.

    1986-05-01

    Phosphate:2-deoxyglucose 6-phosphate (Pi:2DG6P) antiport was extracted from Streptococcus lactis or Staphylococcus aureus with 1.1% octylglucoside in the presence of 0.37% E. coli lipid and reconstituted by detergent dilution. Because previous work suggested inactivation at an early stage, the authors introduced protein stabilants during solubilization. When 20% glycerol was used, proteoliposomes showed a 20-fold increase in /sup 32/Pi transport. This enhanced recovery required phospholipid plus glycerol, and was found only when both were added together with the detergent. Glycerol protection yielded proteoliposomes in which antiporters retained their normal kinetic properties, and Pi exchange by the streptococcal example gave a maximal rate (200-400 nmol/min per mg protein) and a turnover number (30-50/s) which suggested that inactivation had been avoided. Further study showed that 20% glycerol could be replaced by equally high concentrations of compounds classified as osmolytes polyols (erythritol, xylitol, sorbitol), sugars (glucose, trehalose) and certain amino acids (glycine, proline, but not valine). The authors suggest that osmolytes may be used to fully stabilize chemiosmotic transporters during reconstitution.

  10. Phosphate retention in an agricultural stream using experimental additions of phosphate

    Science.gov (United States)

    Macrae, M. L.; English, M. C.; Schiff, S. L.; Stone, M. A.

    2003-12-01

    In-stream experiments involving additions of phosphate were conducted to determine the soluble reactive phosphorus (SRP) retention potential of a perennial first-order stream that drains a 2·7 km2 agricultural catchment in southern Ontario. SRP retention was determined in relation to highly elevated SRP concentrations under low flow conditions. Point source treatments of phosphate were added to three reaches of this stream during two time periods when baseline SRP concentrations were notably different (early summer and early autumn). The reaches selected varied with respect to streambed shape and gradient, direction of groundwater flow, and channel vegetation type and density. One of the three experimental stream reaches was dredged between the two sampling periods, so that all vegetation and the top 25 cm of sediments were removed.SRP retention in the stream ranged from 0·8 to 24·1 µg m-2 s-1. Dredging the stream sediments did not alter the ability of the stream to remove SRP from the water column. SRP retention over the experimental reaches was generally 5-10% of the elevated concentration (0·7-4·2 mg l-1, a factor of 8-53 above pre-experiment conditions), although low-flow conditions in the stream were conducive to retention by stream sediments. Copyright

  11. Fabrication of Phosphate Cement with High Integrity

    International Nuclear Information System (INIS)

    As the development of industrial society has accelerated, hazardous wastes are generated as well. According to the 1986 statistics of U.S.A, each person made 40 tons of waste in America that year. Treatment of radioactive waste is one of the most important and serious problems related to waste treatments, because its radioactivity and decaying heat have harmful effects to human and environment for a long time. Nuclear developed countries have used conventional method of treatment such as vitrification or cementation in order to stabilize and solidify radioactive waste. Although the former guarantees the formation of high leaching resistant and durable waste form, it requires several hundred (or even more than one thousand) temperature to melt glass frit. This process generates secondary waste volatilized, as well as being non-economical. Cement technology played a role of immobilizing low and middle class wastes. It has advantages of low temperature setting, low cost, easy process, etc. The alkalinity of ordinary cement, however, constrains the utility of cement to the solidification of alkaline waste. In addition, leachability and mechanical strength of cements are not quite appropriate for the stabilization of high level waste. In this regard, chemically bonded phosphate cement(CBPC), which sets by an acid-base reaction, is a potentially expectable material for immobilization of radioactive waste. CBPC not only sets at room temperature, but also encapsulates various isotopes chemically. The performance of CBPC can be enhanced by the addition of fly ash, sand, wollastonite, etc. This study aims at fabricating the CBPC containing fly ash with high integrity. Morphology, microstructure, and compressive strength are evaluated using SEM, and digital compressing machine

  12. Fabrication of Phosphate Cement with High Integrity

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jae Hwan; Lee, Chang Hwa; Heo, Cheol Min; Jeon, Min Ku; Kang, Kweon Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-05-15

    As the development of industrial society has accelerated, hazardous wastes are generated as well. According to the 1986 statistics of U.S.A, each person made 40 tons of waste in America that year. Treatment of radioactive waste is one of the most important and serious problems related to waste treatments, because its radioactivity and decaying heat have harmful effects to human and environment for a long time. Nuclear developed countries have used conventional method of treatment such as vitrification or cementation in order to stabilize and solidify radioactive waste. Although the former guarantees the formation of high leaching resistant and durable waste form, it requires several hundred (or even more than one thousand) temperature to melt glass frit. This process generates secondary waste volatilized, as well as being non-economical. Cement technology played a role of immobilizing low and middle class wastes. It has advantages of low temperature setting, low cost, easy process, etc. The alkalinity of ordinary cement, however, constrains the utility of cement to the solidification of alkaline waste. In addition, leachability and mechanical strength of cements are not quite appropriate for the stabilization of high level waste. In this regard, chemically bonded phosphate cement(CBPC), which sets by an acid-base reaction, is a potentially expectable material for immobilization of radioactive waste. CBPC not only sets at room temperature, but also encapsulates various isotopes chemically. The performance of CBPC can be enhanced by the addition of fly ash, sand, wollastonite, etc. This study aims at fabricating the CBPC containing fly ash with high integrity. Morphology, microstructure, and compressive strength are evaluated using SEM, and digital compressing machine

  13. Uranium recovery from phosphates in Romania

    International Nuclear Information System (INIS)

    The history of laboratory and pilot-scale research work carried out in Romania is reviewed. Based on this work, three industrial-scale uranium recovery units have been built adjacent to the existing plants that produce phosphoric acid for fertilizer production. The process described uses solvent extraction for recovering uranium from phosphoric acid (sulfuric acid attack) and from phosphonitric acid (nitric acid attack). The extractant used is either a DEPA-TOPO mixture or a mixture of DEPA-TBP. The method selected for the industrial-scale units is a ''one-cycle, extraction-stripping process'' that differs from the ''two-cycle, extraction stripping process'' developed by the Oak Ridge National Laboratory (ORNL). In the ''one-cycle method'' both uranium and the rare earths are co-extracted and then selectively stripped by techniques that simultaneously produce precipitates. The first stripping operation selectively recovers a rare earth precipitate. Uranium is obtained from the second-stage stripping operation as ''green cake'' (a fluoride of U4+), which can be readily transformed to high purity UFO6. The treated phosphoric acid produces a triple superphosphate (TSP) of low radioactivity and diammonium phosphate (DAP) of no radioactivity. Three uranium recovery plants have been built adjacent to the existing phosphoric acid plants and are to be put into operation soon. Each plant can produce approximately 30 tonnes per year of uranium. The technology for conversion of the ''green cake'' to nuclear grade diuranate has also been finalized. Estimates indicate tha the ''one-cycle extraction-stripping process'' has a lower capital investment cost than the ''two-cycle extraction-stripping process'', and the projected operating costs are 25-30 US$/kg of U. (author). 8 refs, 2 figs

  14. Distinct generation, pharmacology, and distribution of sphingosine 1-phosphate and dihydro-sphingosine 1-phosphate in human neural progenitor cells

    Science.gov (United States)

    In-vivo and in-vitro studies suggest a crucial role for Sphingosine 1-phosphate (S1P) and its receptors in the development of the nervous system. Dihydrosphingosine 1-phosphate (dhS1P), a reduced form of S1P, is an active ligand at S1P receptors, but the pharmacology and physiology of dhS1P has not...

  15. Effect of casein phosphopeptide-amorphous calcium phosphate and acidulated phosphate fluoride gel on erosive enamel wear

    OpenAIRE

    Maryam HajeNorouz Ali Tehrani; Maryam Ghafournia; Pouran Samimi; Omid Savabi; Iman Parisay; Navid Askari; Seyed-Hossein Abtahi

    2011-01-01

    Background: Some studies have shown that casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and acidulated phosphate fluoride (APF) gel can protect teeth against erosion. The aim of this study was to assess whether CPP-ACP and fluoride could reduce enamel wear rates under erosive conditions simulating abrasion and acidic diet regimen. Materials and Methods: Enamel specimens consisted of 3 experimental groups (receiving CPP-ACP, APF or both) and a control group. Specimens were sub...

  16. Effect of casein phosphopeptide-amorphous calcium phosphate and acidulated phosphate fluoride gel on erosive enamel wear

    OpenAIRE

    Tehrani, Maryam HajeNorouz Ali; Ghafournia, Maryam; Samimi, Pouran; Savabi, Omid; Parisay, Iman; Askari, Navid; Abtahi, Seyed-Hossein

    2011-01-01

    Background: Some studies have shown that casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and acidulated phosphate fluoride (APF) gel can protect teeth against erosion. The aim of this study was to assess whether CPP-ACP and fluoride could reduce enamel wear rates under erosive conditions simulating abrasion and acidic diet regimen. Materials and Methods: Enamel specimens consisted of 3 experimental groups (receiving CPP-ACP, APF or both) and a control group. Specimens were subject...

  17. Ribose-5-Phosphate Isomerase Deficiency: New Inborn Error in the Pentose Phosphate Pathway Associated with a Slowly Progressive Leukoencephalopathy

    OpenAIRE

    Huck, Jojanneke H. J.; Verhoeven, Nanda M; Struys, Eduard A.; Salomons, Gajja S; Jakobs, Cornelis; van der Knaap, Marjo S.

    2004-01-01

    The present article describes the first patient with a deficiency of ribose-5-phosphate isomerase (RPI) (Enzyme Commission number 5.3.1.6) who presented with leukoencephalopathy and peripheral neuropathy. Proton magnetic resonance spectroscopy of the brain revealed highly elevated levels of the polyols ribitol and D-arabitol, which were subsequently also found in high concentrations in body fluids. Deficient activity of RPI, one of the pentose-phosphate-pathway (PPP) enzymes, was demonstrated...

  18. Comparative expression profiling reveals a role of the root apoplast in local phosphate response

    OpenAIRE

    Hoehenwarter, Wolfgang; Mönchgesang, Susann; Neumann, Steffen; Majovsky, Petra; Abel, Steffen; Jens MÜLLER

    2016-01-01

    Background Plant adaptation to limited phosphate availability comprises a wide range of responses to conserve and remobilize internal phosphate sources and to enhance phosphate acquisition. Vigorous restructuring of root system architecture provides a developmental strategy for topsoil exploration and phosphate scavenging. Changes in external phosphate availability are locally sensed at root tips and adjust root growth by modulating cell expansion and cell division. The functionally interacti...

  19. Salivary Phosphate-Binding Chewing Gum Reduces Hyperphosphatemia in Dialysis Patients

    OpenAIRE

    Savica, Vincenzo; Calò, Lorenzo A.; Monardo, Paolo; Davis, Paul A.; Granata, Antonio; Santoro, Domenico; Savica, Rodolfo; Musolino, Rosa; Comelli, Maria Cristina; Bellinghieri, Guido

    2009-01-01

    In uremic patients, hyperphosphatemia is associated with cardiovascular calcification and increased cardiovascular mortality. Despite the use of phosphate binders, only half of hemodialysis (HD) patients achieve recommended serum phosphate levels. A hyperphosphoric salivary content, which correlates linearly with serum phosphate, has been reported in HD patients. We hypothesized that binding salivary phosphate during periods of fasting in addition to using phosphate binders with meals could i...

  20. Intestinal Npt2b Plays a Major Role in Phosphate Absorption and Homeostasis

    OpenAIRE

    Sabbagh, Yves; O'Brien, Stephen P.; Song, Wenping; Boulanger, Joseph H; Stockmann, Adam; Arbeeny, Cynthia; Schiavi, Susan C.

    2009-01-01

    Intestinal phosphate absorption occurs through both a paracellular mechanism involving tight junctions and an active transcellular mechanism involving the type II sodium-dependent phosphate cotransporter NPT2b (SLC34a2). To define the contribution of NPT2b to total intestinal phosphate absorption, we generated an inducible conditional knockout mouse, Npt2b−/− (Npt2bfl/fl:Cre+/−). Npt2b−/− animals had increased fecal phosphate excretion and hypophosphaturia, but serum phosphate remained unchan...

  1. Benefits of Phosphate Rocks in Crop Production: Experience on Benchmark Tropical Soil Areas in Nigeria

    OpenAIRE

    Ezekiel Akinkunmi Akinrinde; Gabriel Olufemi Obigbesan

    2006-01-01

    Paucity of research information on the agronomic effectiveness of Nigerian phosphate rocks had until recently hindered their direct application by farmers. We have investigated the behaviour of some indigenous phosphate rocks (Ogun Phosphate Rock, ORP and Sokoto Phosphate Rock, SRP) under laboratory; greenhouse and field plot conditions. Their physico-chemical and mineralogical properties as well as phosphate release in strongly acidic and mildly acid soil types and different moisture regimes...

  2. Exploring plant factors for increasing phosphorus utilization from rock phosphates and native soil phosphates in acidic soils

    International Nuclear Information System (INIS)

    Six plant species with contrasting capacity in utilizing rock phosphates were compared with regard to their responses to phosphorus starvation in hydroponic cultures. Radish, buckwheat and oil rapeseed are known to have strong ability to use rock phosphates while ryegrass, wheat and sesbania are less efficient. Whereas other plants acidified their culture solution under P starvation (-P), radish plants make alkaline the solution. When neutralizing the pH of the solutions cultured with plants under either -P or + P conditions, solutions with P starved buckwheat, rapeseed, and radish had a higher ability to solubilize Al and Fe phosphates than did those cultured with sesbania, ryegrass and wheat. Characterization of organic ligands in the solutions identified that citrate and malate were the major organic anions exuded by rapeseed and radish. Besides citrate and malate, buckwheat exuded a large amount of tartrate under P starvation. In contrast, ryegrass, wheat and sesbania secreted only a limited amount of oxalic acid, regardless of P status. Changes in activities of phosphoenolpyruvate carboxylase, acid phosphatase, and nitrate reductase in these plants were also compared under P- sufficient or -deficient conditions. The results indicated that plant ability to use rock phosphates or soil phosphates is closely related to their responses toward P starvation. The diversity of P starvation responses was discussed in the context of co-evolution between plants and their environment. Approaches to use plant factors to enhance the effectiveness of rock phosphates were also discussed. (author)

  3. Characterization of phosphate solubilizing bacteria isolated from Pb contaminated soils and their potential for dissolving tricalcium phosphate

    Directory of Open Access Journals (Sweden)

    L.E. Susilowati

    2014-01-01

    Full Text Available Phosphorus solubilizing bacteria (PSB enhances P availability in soils through dissolving inorganic P pools. The characteristics of PSB and the potential of three Pb tolerant phosphate solubilizing rhizobacteria, i.e. Pseudomonassp, Bacillus sp., and Actinomycites sp. were evaluated. PSB were isolated from soil samples contaminated with 300 and 500 mg Pb/kg after incubation for 30 days. Phosphate solubilizing bacteria were screened on for phosphate solubilisation ability in Pikovskaya agar medium (PA. In addition, two of the three indentified PSB strains (Pseudomonas sp. and Bacillus sp. were characterized for their ability to solubilize tricalcium phosphate in Pikoskaya broth (PB and also were examined their growth during culture medium incubation. The isolates exhibited different phosphate solubilization index, ranging from 1.87 to 2.98. Pseudomonas sp. had the highest ability to solubilize tricalcium phosphate: 9.82 mg P/ L and 12.23 mg P/ L in Pikoskaya broth following the addition of 4 mg Pb/L and 2 mg /Pb L, respectively.

  4. Characterization of a calcium phosphate cement based on alpha-tricalcium phosphate obtained by wet precipitation process

    International Nuclear Information System (INIS)

    There are several systems of calcium phosphate cements being studied. Those based on alpha-tricalcium phosphate are of particular interest. After setting they produce calcium deficient hydroxyapatite similar to bone like hydroxyapatite. This work aims to obtain alpha-tricalcium phosphate powders by the wet precipitation process, using calcium nitrate and phosphoric acid as reagents. This powder was characterized by infrared spectroscopy, X-ray diffraction and particle size distribution. In order to prepare the calcium phosphate cement, the powder was mixed with an accelerator in an aqueous solution. The mechanical properties of the cement were assessed and it was evaluated by means of apparent density, X-ray diffraction and scanning electron microscopy. The described method produced crystalline alpha-tricalcium phosphate as the major phase. The calcium phosphate cement showed high values of compression strength (50 MPa). The soaking of the cement in a simulated body fluid (SBF) formed a layer of hydroxyapatite like crystals in the surface of the samples. (author)

  5. Salivary phosphate-binding chewing gum reduces hyperphosphatemia in dialysis patients.

    Science.gov (United States)

    Savica, Vincenzo; Calò, Lorenzo A; Monardo, Paolo; Davis, Paul A; Granata, Antonio; Santoro, Domenico; Savica, Rodolfo; Musolino, Rosa; Comelli, Maria Cristina; Bellinghieri, Guido

    2009-03-01

    In uremic patients, hyperphosphatemia is associated with cardiovascular calcification and increased cardiovascular mortality. Despite the use of phosphate binders, only half of hemodialysis (HD) patients achieve recommended serum phosphate levels. A hyperphosphoric salivary content, which correlates linearly with serum phosphate, has been reported in HD patients. We hypothesized that binding salivary phosphate during periods of fasting in addition to using phosphate binders with meals could improve the treatment of hyperphosphatemia. We assessed the phosphate-binding capacity of the natural polymer chitosan by (31)P nuclear magnetic resonance and established that 10 and 20% (wt/vol) middle viscosity chitosan solutions bind 30 and 50% of the phosphate contained in PBS, respectively. Thirteen HD patients with serum phosphate levels >6.0 mg/dl despite treatment with sevelamer hydrochloride chewed 20 mg of chitosan-loaded chewing gum twice daily for 2 wk at fast in addition to their prescribed phosphate-binding regimen. Salivary phosphate and serum phosphate significantly decreased during the first week of chewing; by the end of 2 wk, salivary phosphate decreased 55% from baseline (73.21 +/- 19.19 to 33.19 +/- 6.53; P chewing gum, whereas serum phosphate levels took 30 d to return to baseline. Parathyroid hormone and serum calcium concentrations were not affected by the gum. In conclusion, adding salivary phosphate binding to traditional phosphate binders could be a useful approach for improving treatment of hyperphosphatemia in HD patients. PMID:19020004

  6. Phosphate Solubilization Potentials of Rhizosphere Isolates from Central Anatolia (Turkey)

    Science.gov (United States)

    Ogut, M.; Er, F.

    2009-04-01

    Plant available-phosphorus (P) is usually low in Anatolian soils due mainly to the precipitation as calcium (Ca) and magnesium (Mg) phosphates in alkaline conditions. Phosphate solubilizing microorganisms (PSM) can enhance plant P-availability by dissolving the hardly soluble-P within the rhizosphere, which is the zone that surrounds the plant roots. PSM's can be used as seed- or soil-inocula to increase plant P-uptake and the overall growth. A total of 162 PSM's were isolated from the rhizosphere of wheat plants excavated from different fields located along a 75 km part of a highway in Turkey. The mean, the standart deviation, and the median for solubilized-P (ppm) in a 24 h culture in a tricalcium phosphate broth were 681, 427, and 400 for glucose; 358, 266, and 236 for sucrose; and 102, 117, and 50 for starch, respectively. There was not a linear relationship between the phosphate solubilized in the liquid cultures and the solubilization index obtained in the Pikovskaya's agar. Nine isolates representing both weak and strong solubilizers [Bacillus megaterium (5), Bacillus pumilis (1), Pseudomonas syringae pv. phaseolica (1), Pseudomonas fluorescens (1), Arthrobacter aurescens (1) as determined by the 16S rRNA gene sequence analysis] were further studied in a five day incubation. Pseudomonas syringae pv. phaseolica solubilized statistically (P<0.05) higher phosphate (409 ppm) than all the other strains did. There was not a statistically significant (P<0.05) difference in solubilized-P among the Bacillus strains. The pH of the medium fell to the levels between 4 and 5 from the initial neutrality. The phosphate solubilizing strains variably produced gluconic, 2-keto-D-gluconic, glycolic, acetic and butyric acids. The organic acids produced by these microorganisms seem to be the major source of phosphate solubilization in vitro.

  7. ISOLATION AND BIOCHEMICAL CHARACTERIZATION OF PHOSPHATE SOLUBILIZING MICROBES

    Directory of Open Access Journals (Sweden)

    MAHANTESH P AND PATIL CS

    2011-07-01

    Full Text Available Phosphorus (P is one of the essential macronutrients for plant growth and reproduction. Plants acquire Pfrom the soil solution as phosphate anions. However, phosphate anions are extremely reactive and may be immobilizedthrough precipitation with cations such as Ca2+, Mg2+, Fe3+ and Al3+, depending on the particular properties of thesoil and as a result, the phosphate is highly insoluble and unavailable to plants. Application of phosphate-solubilizingfungi (PSF has been added as fertilizer to increase P uptake and plant growth. The improvement of soil fertility is oneof the most common strategies to increase agricultural production. Maintaining high levels of available nitrogen (N andphosphorus (P, the two most limiting nutrients in soil, remains being a challenge.Major researches on biofertilizer have concentrated on understanding and improving N2 fixation. However, it is knownthat every aspect of the process of nodule formation is limited by the availability of P. Legumes like alfalfa and clovershow a high positive response to P supplementation (Gyaneshwar et al., 2002, but most of the supplemented Pbecome unavailable when its reacts with soil components.Many soil microorganisms are able to solubilize this unavailable P through their metabolic activities exudating organicacids, which directly dissolve the rock phosphate, or chelating calcium ions that release P to the solution. Production ofmicrobial metabolites results in a decrease in soil pH, which probably plays an important role in the solubilization (Abd-Alla, 1994.Phosphate solubilizing bacteria (PSB were isolated from the area around Bidar region and screened on the basis oftheir solubilization of inorganic tricalcium phosphate in liquid cultures. Ten strains that had higher solubilization potentialwere selected, and they characterized

  8. Characterization of iron phosphate glasses prepared by microwave heating

    International Nuclear Information System (INIS)

    Phosphate glasses have been investigated since the fifties, because they are relatively easy to prepare, have low melting temperatures (1000 deg C - 1200 deg C), and low glass transition. However, these glasses were very sensitive to humidity, showing a very low chemical durability. Iron phosphate glasses have been prepared by melting inorganic precursors in conventional electric furnaces and induction furnaces. By adding iron, phosphate glasses became chemical resistant and were thought to be used as nuclear waste forms or mechanical resistance fibers. The use of microwaves has been investigated because it makes possible a fast and homogeneous heating of the materials. Microwave promotes the self-heating of the material by the interaction of the external electromagnetic field with the molecules and ions of the material. Niobium phosphate glasses was also produced already through the heating of precursors in microwave ovens. Other glasses containing iron in theirs structure was produced by conventional furnaces and they had your structures analyzed. But even so, it was not still published synthesis of iron phosphate glasses starting from the melting of precursors materials in microwave ovens. In the present work mixtures of (NH4)2HPO4 and Fe3O4 or (NH4)2HPO4 and Fe2O3 were exposed to microwave energy with electromagnetic waves of 2,45 GHz. It was proposed that the absorption of this radiation for the material causes the heating from room temperature to melting temperature. The obtained iron phosphate glasses was analyzed by X-ray diffraction, Moessbauer spectroscopy, and Differential Thermal Analysis. Iron phosphate glasses were also produced in electrical furnaces for comparison. (author)

  9. Effect of dietary phosphate intake on the circadian rhythm of serum phosphate concentrations in chronic kidney disease: a crossover study1234

    OpenAIRE

    Ix, Joachim H.; Anderson, Cheryl AM; Smits, Gerard; Persky, Martha S.; Block, Geoffrey A.

    2014-01-01

    Background: Previous trials of binders in chronic kidney disease (CKD) stages 3–5 have shown only modest changes in serum phosphate but evaluated morning phosphate. It is unknown whether a circadian pattern of phosphate concentrations exists in CKD and is modifiable by dietary manipulation.

  10. METHOD FOR ELECTROCHEMICAL PHOSPHATING OF METAL SURFACES, PARTICULARLY STAINLESS STEEL, AND APPLICATION OF AN AQUEOUS PHOSPHATING SOLUTION FOR SUCH A METHOD

    DEFF Research Database (Denmark)

    1998-01-01

    A method for electrochemical phosphating of metal surfaces, particularly stainless steel, in connection with cold forming of metal workpieces, which method provides the cold formed work-piece with a lubricant after phosphating, involves an electrochemical phosphating through a cathodic process...

  11. Dynamic interplay between uranyl phosphate precipitation, sorption, and phase evolution

    International Nuclear Information System (INIS)

    Highlights: • In all experiments, final concentrations of uranium were lower than U.S. EPA standards. • U–P minerals more stable than chernikovite were slow to develop without sorption. • Heterogeneous nucleation was not observed. • U sorbs much more readily to the goethite than mica in the absence of phosphate. • Nucleation-growth-sorption cycles occur over weeks, not hours, at room temperature. - Abstract: Natural examples demonstrate uranyl-phosphate minerals can maintain extremely low levels of aqueous uranium in groundwaters due to their low solubility. Therefore, greater understanding of the geochemical factors leading to uranyl phosphate precipitation may lead to successful application of phosphate-based remediation methods. However, the solubility of uranyl phosphate phases varies over >3 orders of magnitude, with the most soluble phases typically observed in lab experiments. To understand the role of common soil/sediment mineral surfaces in the nucleation and transformation of uranyl phosphate minerals under environmentally relevant conditions, batch experiments were carried out with goethite and mica at pH 6 in mixed electrolyte solutions ranging from 1–800 μM U and 1–800 μM P. All experiments ended with uranium concentrations below the USEPA MCL for U, but with 2–3 orders of magnitude difference in uranium concentrations. Despite the presence of many cations that are well known to incorporate into less soluble autunite-group minerals, chernikovite rapidly precipitated in all experiments containing U and P, except for solutions with 1 μM U and 1 μM P that were calculated to be undersaturated. Textures of uranyl phosphates observed by AFM and TEM indicate that nucleation was homogenous and independent of the initial mineral content. Comparison of time-course U and P concentrations from the experiments with thermodynamic modeling of solution equilibria demonstrated that aqueous uranium concentrations in the experimental systems evolved

  12. Antimicrobial effects of silver zeolite, silver zirconium phosphate silicate and silver zirconium phosphate against oral microorganisms

    Institute of Scientific and Technical Information of China (English)

    Sirikamon Saengmee-anupharb; Toemsak Srikhirin; Boonyanit Thaweboon; Sroisiri Thaweboon; Taweechai Amornsakchai; Surachai Dechkunakorn; Theeralaksna Suddhasthira

    2013-01-01

    Objective: To evaluate the antimicrobial activities of silver inorganic materials, including silver zeolite (AgZ), silver zirconium phosphate silicate (AgZrPSi) and silver zirconium phosphate (AgZrP), against oral microorganisms. In line with this objective, the morphology and structure of each type of silver based powders were also investigated. Methods: The antimicrobial activities of AgZ, AgZrPSi and AgZrP were tested against Streptococcus mutans, Lactobacillus casei, Candidaalbicans and Staphylococcus aureus using disk diffusion assay as a screening test. The minimum inhibitory concentration (MIC) and minimum lethal concentration (MLC) were determined using the modified membrane method. Scanning electron microscope and X-ray diffraction were used to investigate the morphology and structure of these silver materials. Results: All forms of silver inorganic materials could inhibit the growth of all test microorganisms. The MIC of AgZ, AgZrPSi and AgZrP was 10.0 g/L whereas MLC ranged between 10.0-60.0 g/L. In terms of morphology and structure, AgZrPSi and AgZrP had smaller sized particles (1.5-3.0 µm) and more uniformly shaped than AgZ. Conclusions: Silver inorganic materials in the form of AgZ, AgZrPSi and AgZrP had antimicrobial effects against all test oral microorganisms and those activities may be influenced by the crystal structure of carriers. These results suggest that these silver materials may be useful metals applied to oral hygiene products to provide antimicrobial activity against oral infection.

  13. CHARACTERIZATION OF HIGH PHOSPHATE RADIOACTIVE TANK WASTE AND SIMULANT DEVELOPMENT

    International Nuclear Information System (INIS)

    A sample of high-level radioactive tank waste was characterized to provide a basis for developing a waste simulant. The simulant is required for engineered-scaled testing of pretreatment processes in a non-radiological facility. The waste material examined was derived from the bismuth phosphate process, which was the first industrial process implemented to separate plutonium from irradiated nuclear fuel. The bismuth phosphate sludge is a complex mixture rich in bismuth, iron, sodium, phosphorus, silicon, and uranium. The form of phosphorus in this particular tank waste material is of specific importance because that is the primary component (other than water-soluble sodium salts) that must be removed from the high-level waste solids by pretreatment. This work shows unequivocally that the phosphorus present in this waste material is not present as bismuth phosphate. Rather, the phosphorus appears to be incorporated mostly into an amorphous iron(III) phosphate species. The bismuth in the sludge solids is best described as bismuth ferrite, BiFeO3. Infrared spectral data, microscopy, and thermal analysis data are presented to support these conclusions. The behavior of phosphorus during caustic leaching of the bismuth phosphate sludge solids is also discussed.

  14. Spectroscopic properties of highly Nd-doped lead phosphate glass

    International Nuclear Information System (INIS)

    The spectroscopic characteristics of highly Nd3+-doped lead phosphate glasses (xNd:Pb3(PO4)2) have been investigated. The X-ray spectra show that the matrices are glassy up to 25 wt% of Nd3+ doping. From the Judd–Ofelt analysis we observe that while the Ω(2) parameter remains constant indicating that the 4fN and 4fN−15 d1 configurations are not affected by the Nd3+ doping, the behavior of both Ω(4) and Ω(6) changes for 15 wt% of Nd3+ doping. The reduction of the Ω(6) parameter is related to the increase of the covalence bonding between the ligands and the Nd3+ ions. At this particular concentration, the radiative lifetime has a four-fold enhancement. Such behaviors are likely to be related to a modification in the glass structure for high Nd3+ concentrations. - Graphical abstract: Highly doped lead-phosphate glass matrix, with nominal concentration of up to 25 wt%, maintain the spectroscopic properties without deterioration. The analysis concerning the point of view of Nd3+ ions showed that high concentrations only affects the rare earth electronic charge density distribution. - Highlights: • Spectroscopic characterization of Nd2O3 highly doped lead phosphate glasses. • Phosphate glass doped with Nd3+ for applications in photonic devices. • Judd–Ofelt analysis in phosphate glasses doped with Neodymium

  15. Characterisation of phosphate rocks at kurun mountain, Sudan

    International Nuclear Information System (INIS)

    This main objective of this study was to characterise some Sudanese phosphate raw materials collected from Jebel Kurun, located in the eastern part of Nuba Mountain, Western Sudan. The study also aimed to investigate the association between uranium and phosphate and to determine the concentration of some essential elements and trace elements in the phosphate rock. A total of 30 samples were collected from Karun's eastran mountains, near Abujibiha City and have been analyzed for the selected elements using x-ray fluorescence. The obtained results showed that the average concentration of elements was Ca (11.3) and Fe (1.7) as a percentage, while it was Cu (1617.7), Ni (258.4), Pb (185.9), Ti (27.62), V (3779.9), U (160.9), Zn (152.8) and Mn (776.3) in ppm. The average total phosphorus content (analyzed as PO5%) using UV-visible spectrometer was found to be 30.54%. This could be considered is acceptable percentage for phosphate to be 30.54%. This could be considered is acceptable percentage for phosphate to be used in industrial fertilizers and phosphoric acid production. The average total calcium carbonate was 15.7%. For the elements distribution, uranium found to be more concentrated in the summit of Jebel Kurun, and it displayed a correlation with lead. Furthermore, four groups of association have been noticed, based on elements concentrations.(Author)

  16. Decontamination of liquid radioactive waste by thorium phosphate

    International Nuclear Information System (INIS)

    In the field of the complete reexamination of the chemistry of thorium phosphate and of the improvement of the homogeneity of Thorium Phosphate Diphosphate (TPD, Th4(PO4)4P2O7) prepared at high temperature, several crystallized compounds were prepared as initial powdered precursors. Due to the very low solubility products associated to these phases, their use in the field of the efficient decontamination of high-level radioactive liquid waste containing actinides (An) was carefully considered. Two main processes (called 'oxalate' and 'hydrothermal' chemical routes) were developed through a new concept combining the decontamination of liquid waste and the immobilization of the actinides in a ceramic matrix (TPD). In phosphoric media ('hydrothermal route'), the key-precursor was the Thorium Phosphate Hydrogen Phosphate hydrate (Th2(PO4)2(HPO4). H2O, TPHP, solubility product log(KS,00) ∼ - 67). The replacement of thorium by other tetravalent actinides (U, Np, Pu) in the structure, leading to the preparation of Th2-x/2Anx/2(PO4)2(HPO4). H2O solid solutions, was examined. A second method was also considered in parallel to illustrate this concept using the more well-known precipitation of oxalate as the initial decontamination step. For this method, the final transformation to single phase TPD containing actinides was purchased by heating a mixture of phosphate ions with the oxalate precipitate at high temperature. (authors)

  17. Phosphate fertilizer impacts on glyphosate sorption by soil.

    Science.gov (United States)

    Munira, Sirajum; Farenhorst, Annemieke; Flaten, Don; Grant, Cynthia

    2016-06-01

    This research examined the impact of field-aged phosphate and cadmium (Cd) concentrations, and fresh phosphate co-applications, on glyphosate sorption by soil. Soil samples were collected in 2013 from research plots that had received, from 2002 to 2009, annual applications of mono ammonium phosphate (MAP) at 20, 40 and 80 kg P ha(-1) and from products containing 0.4, 70 or 210 mg Cd kg(-1) as an impurity. A series of batch equilibrium experiments were carried out to quantify the glyphosate sorption distribution constant, Kd. Extractable Cd concentrations in soil had no significant effect on glyphosate sorption. Glyphosate Kd values significantly decreased with increasing Olsen-P concentrations in soil, regardless of the pH conditions studied. Experiments repeated with a commercially available glyphosate formulation showed statistically similar results as the experiments performed with analytical-grade glyphosate. Co-applications of MAP with glyphosate also reduced the available sorption sites to retain glyphosate, but less so when soils already contain large amounts of phosphate. Glyphosate Kd values in soils ranged from 173 to 939 L kg(-1) under very strong to strongly acidic condition but the Kd was always glyphosate may become mobile by water in soils with high phosphate levels. Otherwise, glyphosate residues in agricultural soils are more likely to be transported off-site by wind and water-eroded sediments than by leaching or runoff. PMID:27035384

  18. New sunscreen materials based on amorphous cerium and titanium phosphate

    International Nuclear Information System (INIS)

    Cerium-titanium pyrophosphates Ce1-xTi xP2O7 (with x = 0, 0.50, and 1.0), which are novel phosphate materials developed as UV-shielding agents for use in cosmetics, were characterized by X-ray diffraction, X-ray fluorescent analysis, UV-vis reflectance, and Raman spectroscopy. Since the optical reflectance shifted to lower wavelengths by the crystallization of the phosphates and the stabilization of the amorphous state of the cerium-titanium pyrophosphates was carried out by doping niobium (Nb). Raman spectroscopic study of the phosphate showed that P-O-P bending and stretching modes decreased with the loading of Nb, accompanying with the formation of Nb-O stretching mode. Therefore, the increase in the amount of the non-bridging oxygen in the amorphous phosphate should be the reason for the inhibition of the crystallization. This stabilization is a significant improvement, which enables to apply these amorphous phosphates not only to cosmetics and paints, but also plastics and films

  19. Optimization of calcium phosphate fine ceramic powders preparation

    Science.gov (United States)

    Sezanova, K.; Tepavitcharova, S.; Rabadjieva, D.; Gergulova, R.; Ilieva, R.

    2013-12-01

    The effect of biomimetic synthesis method, reaction medium and further precursor treatments on the chemical and phase composition, crystal size and morphology of calcium phosphates was examined. Nanosized calcium phosphate precursors were biomimetically precipitated by the method of continuous precipitation in three types of reaction media at pH 8: (i) SBF as an inorganic electrolyte system; (ii) organic (glycerine) modified SBF (volume ratio of 1:1); (iii) polymer (10 g/l xanthan gum or 10 g/l guar gum) modified SBF (volume ratio of 1:1). After maturation (24 h) the samples were lyophilized, calcinated at 300°C for 3 hours, and washed with water, followed by new gelation, lyophilization and step-wise (200, 400, 600, 800, and 1000°C, each for 3 hours) sintering. The reaction medium influenced the chemical composition and particle size but not the morphology of the calcium phosphate powders. In all studied cases bi-phase calcium phosphate fine powders with well-shaped spherical grains, consisting of β-tricalcium phosphate (β-TCP) and hydroxyapatite (HA) with a Ca/P ratio of 1.3 - 1.6 were obtained. The SBF modifiers decreased the particle size of the product in the sequence guar gum ˜ xanthan gum < glycerin < SBF medium.

  20. Iron phosphate glass for immobilization of 99Tc

    International Nuclear Information System (INIS)

    Highlights: •99Tc (surrogated by Re) was immobilized in an iron phosphate glass. •∼1.1 mass% Re was retained, possibly dissolved, in the iron phosphate glass. •The 7-day PCT normalized release of Re was −2 g/m2. •Re concentration in the glass rapidly decreased with increasing melting temperature and duration. -- Abstract: Technetium-99 (99Tc) can bring serious environmental threats because of its long half-life (τ1/2 = ∼2.1 × 105 years), high fission yield (∼6%), and high solubility and mobility in the ground water. The high volatility makes it difficult to immobilize 99Tc in continuous melters vitrifying 99Tc-containing nuclear wastes in borosilicate glasses. This work explores a possibility of incorporating a high concentration of 99Tc, surrogated by the non-radioactive Re, in an iron phosphate glass by melting mixtures of iron phosphate glass frits with 1.5–6 mass% KReO4 at ∼1000 °C. The retention of Re achieved was ∼1.1 mass%. The normalized Re release by the 7-day Product Consistency Test was −2 g/m2. Surprisingly, the Re escaped from the melt within a short time of heating, especially when the temperature was increased. Therefore, 99Tc volatilization would still be a challenging task for its immobilization in iron phosphate glasses

  1. Amorphous calcium phosphate and its application in dentistry

    Directory of Open Access Journals (Sweden)

    Sun Wei-bin

    2011-07-01

    Full Text Available Abstract Amorphous Calcium Phosphate (ACP is an essential mineral phase formed in mineralized tissues and the first commercial product as artificial hydroxyapatite. ACP is unique among all forms of calcium phosphates in that it lacks long-range, periodic atomic scale order of crystalline calcium phosphates. The X-ray diffraction pattern is broad and diffuse with a maximum at 25 degree 2 theta, and no other different features compared with well-crystallized hydroxyapatite. Under electron microscopy, its morphological form is shown as small spheroidal particles in the scale of tenths nanometer. In aqueous media, ACP is easily transformed into crystalline phases such as octacalcium phosphate and apatite due to the growing of microcrystalline. It has been demonstrated that ACP has better osteoconductivity and biodegradability than tricalcium phosphate and hydroxyapatite in vivo. Moreover, it can increase alkaline phosphatase activities of mesoblasts, enhance cell proliferation and promote cell adhesion. The unique role of ACP during the formation of mineralized tissues makes it a promising candidate material for tissue repair and regeneration. ACP may also be a potential remineralizing agent in dental applications. Recently developed ACP-filled bioactive composites are believed to be effective anti-demineralizing/remineralizing agents for the preservation and repair of tooth structures. This review provides an overview of the development, structure, chemical composition, morphological characterization, phase transformation and biomedical application of ACP in dentistry.

  2. Inorganic phosphate inhibits sympathetic neurotransmission in canine saphenous veins

    International Nuclear Information System (INIS)

    Inorganic phosphate has been proposed as the initiator of metabolic vasodilatation in active skeletal muscle. The present study was primarily designed to determine if this substance has an inhibitory effect on adrenergic neurotransmission. Rings of canine saphenous veins were suspended for isometric tension recording in organ chambers. A comparison was made of the ability of inorganic phosphate (3 to 14 mM) to relax rings contracted to the same degree by electrical stimulation, exogenous norepinephrine, and prostaglandin F/sub 2α/. The relaxation during electrical stimulation was significantly greater at all concentrations of phosphate. In strips of saphenous veins previously incubated with [3H]norepinephrine, the depression of the contractile response caused by phosphate during electrical stimulated was accompanied by a significant reduction in the overflow of labeled neurotransmitter. Thus inorganic phosphate inhibits sympathetic neurotransmission and hence may have a key role in the sympatholysis in the active skeletal muscles during exercise. By contrast, in this preparation, it has a modest direct relaxing action on the vascular smooth muscle

  3. Occupational radiation exposure in the Florida phosphate industry

    International Nuclear Information System (INIS)

    Uranium and its decay series are associated with phosphate deposits; consequently, phosphate mining and chemical processing present the potential for exposure to 'technologically enhanced natural radiation'. Exposure to Florida phosphate workers was studied by determining the radium content of various materials in mining and processing and measuring gamma radiation, airborne short-lived radon progeny and airborne long-lived alpha radioactivity. Radiation exposures were generally within occupational limits and levels were sufficiently low to qualify most areas as non-restricted areas. However, several areas and operations were identified as potentially requiring restricted area procedures. Radium is concentrated in sediment and scale in phosphoric acid production tanks, filters, and piping, and it was recommended that special close-contact operations such as cleaning and maintenance in these areas be individually evaluated to determine the need for further survey and personnel monitoring. While airborne radon progeny concentrations were below permissible levels in well-ventilated rock-loading tunnels, high occupancy of poorly ventilated tunnels presents the opportunity for cumulative exposures on the order of occupational limits. Improved ventilation and continued surveillance were recommended for these tunnels and any other occupied spaces of limited ventilation containing significant inventories of phosphate rock or products. Airborne long-lived alpha radioactivity concentrations in selected dry rock and fertilizer handling operations prompted a recommendation of further surveillance and possible reduction of dustiness, decrease of occupancy and/or provision of respiratory protection. This work was performed under a contract from the Florida Phosphate Council. (author)

  4. Bypassing the Pentose Phosphate Pathway: Towards Modular Utilization of Xylose.

    Directory of Open Access Journals (Sweden)

    Kulika Chomvong

    Full Text Available The efficient use of hemicellulose in the plant cell wall is critical for the economic conversion of plant biomass to renewable fuels and chemicals. Previously, the yeast Saccharomyces cerevisiae has been engineered to convert the hemicellulose-derived pentose sugars xylose and arabinose to d-xylulose-5-phosphate for conversion via the pentose phosphate pathway (PPP. However, efficient pentose utilization requires PPP optimization and may interfere with its roles in NADPH and pentose production. Here, we developed an alternative xylose utilization pathway that largely bypasses the PPP. In the new pathway, d-xylulose is converted to d-xylulose-1-phosphate, a novel metabolite to S. cerevisiae, which is then cleaved to glycolaldehyde and dihydroxyacetone phosphate. This synthetic pathway served as a platform for the biosynthesis of ethanol and ethylene glycol. The use of d-xylulose-1-phosphate as an entry point for xylose metabolism opens the way for optimizing chemical conversion of pentose sugars in S. cerevisiae in a modular fashion.

  5. Development of chemically engineered porous metal oxides for phosphate removal

    International Nuclear Information System (INIS)

    In this study, the application of ordered mesoporous silica (OMS) doped with various metal oxides (Zr, Ti, Fe and Al) were studied for the removal of (ortho) phosphate ions from water by adsorption. The materials were characterized by means of N2 physisorption (BET), powder X-ray diffraction (PXRD) and transmission electron microscopy (TEM). The doped materials had surface areas between 600 and 700 m2 g-1 and exhibited pore sizes of 44-64 A. Phosphate adsorption was determined by measurement of the aqueous concentration of orthophosphate using ultraviolet-visible (UV-vis) spectroscopy before and after extraction. The effects of different metal oxide loading ratios, initial concentration of phosphate solution, temperature and pH effects on the efficiency of phosphate removal were investigated. The doped mesoporous materials were effective adsorbents of orthophosphate and up to 100% removal was observed under appropriate conditions. 'Back extracting' the phosphate from the doped silica (following water treatment) was also investigated and shown to have little adverse effect on the adsorbent.

  6. Bypassing the Pentose Phosphate Pathway: Towards Modular Utilization of Xylose

    Science.gov (United States)

    Chomvong, Kulika; Bauer, Stefan; Benjamin, Daniel I.; Li, Xin; Nomura, Daniel K.; Cate, Jamie H. D.

    2016-01-01

    The efficient use of hemicellulose in the plant cell wall is critical for the economic conversion of plant biomass to renewable fuels and chemicals. Previously, the yeast Saccharomyces cerevisiae has been engineered to convert the hemicellulose-derived pentose sugars xylose and arabinose to d-xylulose-5-phosphate for conversion via the pentose phosphate pathway (PPP). However, efficient pentose utilization requires PPP optimization and may interfere with its roles in NADPH and pentose production. Here, we developed an alternative xylose utilization pathway that largely bypasses the PPP. In the new pathway, d-xylulose is converted to d-xylulose-1-phosphate, a novel metabolite to S. cerevisiae, which is then cleaved to glycolaldehyde and dihydroxyacetone phosphate. This synthetic pathway served as a platform for the biosynthesis of ethanol and ethylene glycol. The use of d-xylulose-1-phosphate as an entry point for xylose metabolism opens the way for optimizing chemical conversion of pentose sugars in S. cerevisiae in a modular fashion. PMID:27336308

  7. Recovery of uranium from phosphatic rock and its derivatives

    International Nuclear Information System (INIS)

    The recovery of uranium present in the manufacture process of phosphoric acid and fertilizers has been one interesting field of study in chemistry. It is true that the recovery of uranium it is not very attractive from the commercial point of view, however the phosphatic fertilizers have an important amount of uranium which comes from the starting materials (phosphatic rock), therefore there must be many tons of uranium that are dispersed in the environmental together with the fertilizers used in agriculture every year. They are utilized for the enrichment of the nutrients which are exhausted in the soil. In this work, uranium was identified and quantified in the phosphatic rocks and in inorganic fertilizers using Gamma Spectroscopy, Neutron Activation Analysis, UV/Visible Spectrophotometry, Alpha Spectroscopy. On the other hand, it was done a correlation of the behaviour of uranium with inorganic elements present in the samples such as phosphorus, calcium and iron; which were determined by UV/Visible Spectrophotometry for phosphorus and Atomic Absorption Spectrometry for calcium and iron. The quantity of uranium found in the phosphatic rock, phosphoric acid and fertilizers was considerable (70-200 ppm). The adequate conditions for the recovery of 40% of total of uranium from the phosphatic rock with the addition of leaching solutions were stablished. (Author)

  8. Lar mountain phosphate ore processing using flotation approach

    International Nuclear Information System (INIS)

    The sample of Lar Mountain Phosphate deposit which is located in the southwest of Iran, was studied to upgrade its phosphate grade. The results obtained from mineralogical studies showed the presence of apatite, CaO, Al2O3, Fe2O3 and SiO2, in which carbonate was detected as the main gangue. Two sets of direct and reverse flotation tests were performed using samples from this deposit with 10% P2O5. In phosphate flotation (direct approach), the samples were conditioned with sodium silica, oleic acid-fuel oil and Armac T-fuel oil. The direct flotation at pH=9.2 yielded a product with 23.2% of P2O5 and 75.16% recovery. The reverse flotation tests were carried out at pH=5.2, with floating carbonate and pulp de-oiling, using H2SO4 and wash water, and phosphate was then floated from siliceous gangue. In the second sets of the reverse approach, depressing the phosphate and floating silica with Amines in natural pH were done. However the best concentrate assay was 31.2% P2O5 with a 71.12% recovery, which was obtained from reverse tests

  9. Investigation of calcium phosphate coatings for biomedical applications

    International Nuclear Information System (INIS)

    Calcium phosphate is the main constituent of our bone and tooth minerals. The use of this bioactive material for coating implant such as artificial joint prosthesis, therefore, can promote biological fixation and enhance biocompatibility. Our initial work has been focused on the evaluation of experimental conditions of coating preparation and the effects of post-deposition calcium phosphate coatings on stainless steel substrates. The coating layers were produced by the precipitation technique and coatings were carried out in sol-gel by the dipping method. For comparison purposes a wet method was used to obtain a fine calcium phosphate ceramic powder for fabrication of microcrystal suspension used as a coating material. Scanning electron microscopy (SEM), energy dispersive microanalysis (EDS), energy dispersive x-ray fluorescence (EDXRF) and x-ray diffraction (XRD) were used to characterise the morphology, chemical composition and structure of the coatings. The results showed that the dip coating of stainless steel substrates using viscous solutions lead to the formation of porous calcium phosphate layers. These results suggested that fabrication of bioactive calcium phosphate coatings using this route offers significant advantages over the currently used methods due to considerably lower temperature process involved and may produce better result for substrates with complex shapes

  10. New sunscreen materials based on amorphous cerium and titanium phosphate

    Energy Technology Data Exchange (ETDEWEB)

    Masui, Toshiyuki [Department of Applied Chemistry, Faculty of Engineering and Handai Frontier Research Center, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Hirai, Hidekazu [Department of Applied Chemistry, Faculty of Engineering and Handai Frontier Research Center, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Imanaka, Nobuhito [Department of Applied Chemistry, Faculty of Engineering and Handai Frontier Research Center, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan)]. E-mail: imanaka@chem.eng.osaka-u.ac.jp; Adachi, Gin-ya [Juri Institute for Environmental Science and Chemistry, College of Analytical Chemistry, 2-1-8 Temma, Kita-ku, Osaka 530-0043 (Japan)

    2006-02-09

    Cerium-titanium pyrophosphates Ce{sub 1-x}Ti {sub x}P{sub 2}O{sub 7} (with x = 0, 0.50, and 1.0), which are novel phosphate materials developed as UV-shielding agents for use in cosmetics, were characterized by X-ray diffraction, X-ray fluorescent analysis, UV-vis reflectance, and Raman spectroscopy. Since the optical reflectance shifted to lower wavelengths by the crystallization of the phosphates and the stabilization of the amorphous state of the cerium-titanium pyrophosphates was carried out by doping niobium (Nb). Raman spectroscopic study of the phosphate showed that P-O-P bending and stretching modes decreased with the loading of Nb, accompanying with the formation of Nb-O stretching mode. Therefore, the increase in the amount of the non-bridging oxygen in the amorphous phosphate should be the reason for the inhibition of the crystallization. This stabilization is a significant improvement, which enables to apply these amorphous phosphates not only to cosmetics and paints, but also plastics and films.

  11. Assessment of phosphate fertilizers ingredients and their impact on final products

    International Nuclear Information System (INIS)

    Heavy metals contents in raw materials used in phosphate ferthizer industry as well as phosphate products were determined. The samples were collected from abu-zabal phosphate factory in ElQalyobia governorate, Egypt. The samples include: rock phosphate gypsum, limestone, sulfur (as raw materials), sulfuric and phosphoric acids, mono phosphate (soft and granulate) and triple phosphate (as final products). The aim of this study was to determine the elemental pattern in phosphate ingrdient materials as well as the fertilizers produced. The results revealed that the main source of heavy metals in the produced phospate fertilizer is mainly due to the impurities in the long run due to the high application rate of phosphate fertilizer. Senitive heavy metals analytical technique should be employed to determine the heavy metals in the manufactured ingredients to minimize the use of contaminated ones in phosphate industry

  12. PHOSPHATE SOLUBILIZATION BY ALLOCHROMATIUM SP. GSKRLMBKU-01 ISOLATED FROM MARINE WATER OF VISAKHAPATNAM

    Directory of Open Access Journals (Sweden)

    Kadari Rajya Laxmi

    2015-05-01

    Full Text Available Mineral phosphate solu bilization activities by Allochromatium sp. GSKRLMBKU-01 on dicalcium and tricalcium phosphate was investigated. The biomass, di- a nd tricalcium phosphate solubilization increased with the progress of incubation period upto 8 th day and decreased with further incr emental incubation period. The highest solubility of dicalcium phosphate (558.0 ± 9.2 μg P/ml and tricalcium phosphate (568.0 ± 8.0 μg P/ml was recorded on 8 th day of incubation period. The maximum optical density of biomass of the bacterium on dicalcium and tricalcium phosphate was 1.389 ± 0.110 and 1.206 ± 0.108 respectively on 8 th day of incubation period. A positive correlation coefficient (r was recorded between growth, dicalcium phosphate(r=0.965 and tricalcium phosphate (r=0.786 solubilization.

  13. Mechanisms of phosphate removal from aqueous solution by blast furnace slag and steel furnace slag

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    We report the adsorption of phosphate and discuss the mechanisms of phosphate removal from aqueous solution by burst furnace slag (BFS) and steel furnace slag (SFS). The results show that the adsorption of phosphate on the slag was rapid and the majority of adsorption was completed in 5~10 min. The adsorption capacity of phosphate by the slag was reduced dramatically by acid treatment. The relative contribution of adsorption to the total removal of phosphate was 26%~28%. Phosphate adsorption on BFS and SFS follows the Freundlich isotherm, with the related constants ofk 6.372 and 1/n 1.739 for BFS, and ofk 1.705 and 1/n 1.718 for SFS. The pH and Ca2+ concentration were decreased with the addition of phosphate, suggesting the formation of calcium phosphate precipitation. At pH 2.93 and 6.93, phosphate was desorbed by about 36%~43% and 9%~11%, respectively.These results indicate that the P adsorption on the slag is not completely reversible and that the bond between the slag particles and adsorbed phosphate is strong. The X-ray diffraction (XRD) patterns of BFS and SFS before and after phosphate adsorption verify SFS is related to the formation of phosphate calcium precipitation and the adsorption on hydroxylated oxides. The results show that BFS and SFS removed phosphate nearly 100%, indicating they are promising adsorbents for the phosphate removal in wastewater treatment and pollution control.

  14. Natural radioactivity assessment of a phosphate fertilizer plant area

    Directory of Open Access Journals (Sweden)

    S.K. Sahu

    2014-01-01

    Full Text Available Rock phosphate ore processing and disposal of phosphogypsum contribute to enhanced levels of natural radionuclides in the environment. The concentration of naturally occurring radionuclides in soil, rock phosphate and phosphogypsum samples collected around a phosphate fertilizer plant were determined. Also the external background gamma levels were surveyed.238U, 232Th, 226Ra and 40K activities in soil samples were 21–674 Bq/kg, 11–44 Bq/kg, 22–683 Bq/kg and 51–295 Bq/kg respectively. The external background gamma radiation levels in the plant premises were ranging from 48 to 133 nGy/h.

  15. Phosphate solubilizing ability of two Arctic Aspergillus niger strains

    Directory of Open Access Journals (Sweden)

    Shiv Mohan Singh,

    2011-06-01

    Full Text Available Many filamentous fungi were isolated from the soils of Ny-Ålesund, Spitsbergen, Svalbard, and were screened in vitro for their phosphate solubilizing ability. Two strains of Aspergillus niger showed good tricalcium phosphate (TCP solubilizing ability in Pikovskaya's medium. The TCP solubilization index was calculated at varying levels of pH and temperatures. The ability of Aspergillus niger strain-1 to solubilize and release inorganic-P was 285 µg ml–1, while Aspergillus niger strain-2 solubilized 262 µg ml–1 from 0.5% TCP after seven days. This is the first report of TCP solubilization by Arctic strains that may serve as very good phosphate solubilizers in the form of biofertilizer.

  16. Gain Characteristics of Er3+-Doped Phosphate Glass Fibres

    Institute of Scientific and Technical Information of China (English)

    XU Shan-Hui; YANG Zhong-Min; ZHANG Qin-Yuan; DENG Zai-De; JIANG Zhong-Hong

    2006-01-01

    @@ An erbium-doped phosphate glass fibre has been drawn by the rod-in-tube technique in our laboratory. The gain for the Er3+-doped phosphate glass fibre with different pump powers and with different input signal wavelengths is investigated. The 2.2-cm-long fibre, pumped by a single-mode 980-nm fibre-pigtailed laser diode, can provide a net gain per unit length greater than 1.8dB/cm. The pump threshold is about 50mW at the wavelength of 1534nm, and below 70mW at 1550nm. The gain linewidth of the Er3+-doped phosphate glass fibre is greater than 34 nm and can cover the C band in optical communication networks.

  17. Calcium-phosphate-osteopontin particles for caries control

    DEFF Research Database (Denmark)

    Schlafer, Sebastian; Birkedal, Henrik; Olsen, Jakob;

    2016-01-01

    Caries is caused by acid production in biofilms on dental surfaces. Preventing caries therefore involves control of microorganisms and/or the acid produced. Here, calcium-phosphate-osteopontin particles are presented as a new approach to caries control. The particles are made by co-precipitation ......Caries is caused by acid production in biofilms on dental surfaces. Preventing caries therefore involves control of microorganisms and/or the acid produced. Here, calcium-phosphate-osteopontin particles are presented as a new approach to caries control. The particles are made by co......, and the pH always remained above 5.5. Hence, calcium-phosphate-osteopontin particles show potential for applications in caries control....

  18. Formation of calcium phosphate mineral materialcontrolled by microemulsion

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In order to prepare calcium phosphate-based material with nano-structure and bioactivity, natural lecithin and n-tetradecane were used as the amphipile and the oil phase respectively, along with the water phase, to form a microemulsion template. Phosphate mineralization was induced and controlled by the microemulsion. The products, characterized by scanning electronic microscopy, infrared spectroscopy and X-ray diffraction analysis, are composed of lecithin and hydroxyapatite, and possess the nano-structure of sticks, balls and three-dimensional nets connected by tubes. These results show that the microemulsion can be used to control calcium phosphate mineralization for the preparation of biomimetic mineral materials with various nano-structures.

  19. Phosphate-intercalated Ca-Fe-layered double hydroxides: Crystal structure, bonding character, and release kinetics of phosphate

    Science.gov (United States)

    Woo, Myong A.; Woo Kim, Tae; Paek, Mi-Jeong; Ha, Hyung-Wook; Choy, Jin-Ho; Hwang, Seong-Ju

    2011-01-01

    The nitrate-form of Ca-Fe-layered double hydroxide (Ca-Fe-LDH) was synthesized via co-precipitation method, and its phosphate-intercalates were prepared by ion-exchange reaction. According to X-ray diffraction analysis, the Ca-Fe-LDH-NO 3- compound and its H 2PO 4--intercalate showed hexagonal layered structures, whereas the ion-exchange reaction with HPO 42- caused a frustration of the layer ordering of LDH. Fe K-edge X-ray absorption spectroscopy clearly demonstrated that the Ca-Fe-LDH lattice with trivalent iron ions was well-maintained after the ion-exchange with HPO 42- and H 2PO 4-. Under acidic conditions, phosphate ions were slowly released from the Ca-Fe-LDH lattice and the simultaneous release of hydroxide caused the neutralization of acidic media. Fitting analysis based on kinetic models indicated a heterogeneous diffusion process of phosphates and a distinct dependence of release rate on the charge of phosphates. This study strongly suggested that Ca-Fe-LDH is applicable as bifunctional vector for slow release of phosphate fertilizer and for the neutralization of acid soil.

  20. The EIS investigation of powder polyester coatings on phosphated low carbon steel: The effect of NaNO2 in the phosphating bath

    International Nuclear Information System (INIS)

    Highlights: → The effect of NaNO2 on surface morphology of iron-phosphate coatings were determined. → Better corrosion stability of polyester coating on phosphated steel without NaNO2. → EIS results and microscopic examinations correlate well with adhesion measurements. - Abstract: The effect of different type of iron-phosphate coatings on corrosion stability and adhesion characteristic of top powder polyester coating on steel was investigated. Iron-phosphate coatings were deposited on steel in the novel phosphating bath with or without NaNO2 as an accelerator. The corrosion stability of the powder polyester coating was evaluated by electrochemical impedance spectroscopy (EIS), adhesion by pull-off and NMP test, while surface morphology of phosphate coatings were investigated by atomic force microscopy (AFM). The adhesion and corrosion stability of powder polyester coatings were improved with pretreatment based on iron-phosphate coating deposited from NaNO2-free bath.

  1. Potential radiological impact of the phosphate industry on wildlife

    International Nuclear Information System (INIS)

    The activities of the phosphate industry may lead to enhanced levels of naturally occurring radioactivity in terrestrial and aquatic ecosystems. We performed a preliminary environmental risk assessment (ERA) of environmental contamination resulting from the activities of 5 phosphate fertiliser plants (located in Belgium, Spain, Syria, Egypt, Brazil), a phosphate-mine and a phosphate-export platform in a harbour (both located in Syria). These sites were selected because of the availability of information on concentrations of naturally occurring radionuclides in the surrounding environments. Assessments were generally performed considering highest environmental concentrations reported in the studies. The ERICA Tool, operating in a Tier 2 assessment mode, was used to predict radiation dose rates and associated risk to the selected reference organisms using the ERICA default parameter setting. Reference organisms were those assigned as default by the ERICA Tool. Potential impact is expressed as a best estimate risk quotient (RQ) based on a radiation screening value of 10 μGy h−1. If RQ ≤ 1, the environment is considered unlikely to be at risk and further radiological assessment is not deemed necessary. Except for one of the cases assessed, the best estimate RQ exceeded 1 for at least one of the reference organisms. Internal exposure covered for 90–100 % of the total dose. 226Ra or 210Po were generally the highest contributors to the dose. The aquatic ecosystems in the vicinity of the phosphate fertiliser plants in Tessenderlo (Belgium), Huelva (Spain), Goiás (Brazil) and the terrestrial environment around the phosphate mine in Palmyra (Syria) are the ecosystems predicted to be potentially most at risk. - Highlights: • The adjusted highlights Environmental radionuclide enrichment from P-industry warrants risk assessment. • 226Ra and 210Po are the most dose contributing radionuclides. • The total dose rate is strongly driven by the internal exposure.

  2. Conditions promoting and restraining agronomic effectiveness of water-insoluble phosphate sources, in particular phosphate rock (PR): I. Indices of phosphate rock use opportunity (PRUOIS) and of phosphate rock suitability for direct use (PRSIDU)

    International Nuclear Information System (INIS)

    Several issues of phosphate rock (PR) use are discussed in this paper. Maize for green fodder (Zea mays L) and ryegrass (Lolium multiflorum Lam.) were grown in 7 kg of dry soil and in small pots of 1.25 kg dry soil capacity, respectively, on several base unsaturated soils belonging to Hapludoll and Hapludalf soil groups. The amount of phosphate rock (PR) to apply was based on experimental data considering soil adsorbed acidity (Ah), humus content (H2 ), cation exchange capacity (T), sum of exchangeable bases (SEB) and mobile (easily soluble) phosphate content (PAL) in the soil. The factors were combined in a rock phosphate use, opportunity index of the soil (PRUOIS): PRUOIS=(Ah*H2*100)/SEB*100.0245*PAL Rock phosphate suitability for direct use was evaluated by means of the rate of PR-P dissolution (PRPRS) in a 0.6% ammonium heptamolybdate in 0.01M calcium chloride solution (ppm P) and by carbonate content (%CaCO3) in PR. Both of these parameters combined provided a phosphate rock suitability index for direct use (PRSIDU): PRSIDU [ppmP/min]=PRPRS*(1-0.03*CaCO3) Water insoluble P sources studied were PR from Kola-Russia, Morocco, Kneifiss-Siria, El Hassa-Jordan, Gafsa- Tunisia, North-Carolina (USA), and Arad-Israel. All PRs were compared with TSP applied at the same rate of P. Neither PRUOIS or PRSIDU considered separately could satisfactorily explain the variance of PR efficiency. An index obtained by multiplicative combination of PRUOIS x PRSIDU did correlate significantly with indices on the agronomic efficiency of PR. (author)

  3. Casein Phosphopeptide- Amorphous Calcium Phosphate in Dentistry: A Literature Review

    OpenAIRE

    KESKİN, Arş. Gör. Dt. Gül; GÜLER, Yrd. Doç. Dr. Çiğdem

    2013-01-01

    Casein is a phosphoprotein in bovine milk and accounts for almost 80 percent of its total protein. Casein fosfopeptit (CPP) is produced as a result of decomposition of casein with trypsin enzyme using a selective deposition method. CPP can remarkably stabilize calcium phosphate in a state-forming CPPamorphous calcium phosphate (ACP) complex. CPPACP is located in topical gels, sugar-free chewing gum and mint dragees at the present day. In this paper, the effectiveness of CPP-ACP and usage in d...

  4. Tin-phosphate glass anode for sodium ion batteries

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Honma

    2013-11-01

    Full Text Available The electrochemical property of tin-phosphate (designate as GSPO glass anode for the sodium ion battery was studied. During the first charge process, sodium ion diffused into GSPO glass matrix and due to the reduction of Sn2+ to Sn0 state sodiated tin metal nano-size particles are formed in oxide glass matrix. After the second cycle, we confirmed the steady reversible reaction ∼320 mAh/g at 0–1 V cutoff voltage condition by alloying process in NaxSn4. The tin-phosphate glass is a promising candidate of new anode active material that realizes high energy density sodium ion batteries.

  5. The radiological impact of the Belgian phosphate industry

    International Nuclear Information System (INIS)

    The Belgian phosphate industry processes huge amounts of phosphate ore (1.5 to 2 Mton/year) for a wide range of applications, the most important being the production of phosphoric acid, fertilizers and cattle food. Marine phosphate ores show high specific activities of the natural uranium decay series (usually indicated by Ra-226) (e.g. 1200 to 1500 Bq/kg for Moroccan ore). Ores of magmatic origin generally contain less of the uranium and more of the thorium decay series (up to 500 Bq/kg). These radionuclides turn up in by-products, residues or product streams depending on the processing method and the acid used for the acidulation of the phosphate rock. Sulfuric acid is the most widely used, but also hydrochloric acid and nitric acid are applied in Belgium. For Flanders, the northern part of Belgium, we already have a clear idea of the production processes and waste streams. The five Flemish phosphate plants, from 1920 to 2000, handled 54 million ton of phosphate ore containing 65 TBq of radium-226 and 2.7 TBq of thorium- 232. The total surface area of the phosphogypsum and calcium fluoride sludge deposits amounts to almost 300 ha. There is also environmental contamination along two small rivers receiving the waste waters of the hydrochloric production process: the Winterbeek (> 200 ha) and the Grote Laak (12 ha). The data on the impact of the phosphate industry in the Walloon provinces in Belgium is less complete. A large plant produced in 2004 0.8 Mton of phosphogypsum, valorizing about 70 % of the gypsum in building materials (plaster, cement), in fertilizers, and in other products such as paper. The remainder was stored on a local disposal site. The radiological impact of the Belgian phosphate industry on the local population will be discussed. At present most contaminated areas are still recognizable as waste deposits and inaccessible to the population. However as gypsum deposits and other contaminated areas quickly blend in with the landscape, it is

  6. Influence of glyphosate on the copper dissolution in phosphate buffer

    Science.gov (United States)

    Coutinho, C. F. B.; Silva, M. O.; Machado, S. A. S.; Mazo, L. H.

    2007-01-01

    The electrochemical behavior of copper microelectrode in phosphate buffer in the presence of glyphosate was investigated by electrochemical techniques. It was observed that the additions of glyphosate in the phosphate buffer increased the anodic current of copper microelectrode and the electrochemical dissolution was observed. This phenomenon could be associated with the Cu(II) complexation by glyphosate forming a soluble complex. Physical characterization of the surface showed that, in absence of glyphosate, an insoluble layer covered the copper surface; on the other hand, in presence of glyphosate, it was observed a corroded copper surface with the formation of glyphosate complex in solution.

  7. Vitrified chemically bonded phosphate ceramics for immobilization of radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Wagh, Arun S.

    2016-04-05

    A method of immobilizing a radioisotope and vitrified chemically bonded phosphate ceramic (CBPC) articles formed by the method are described. The method comprises combining a radioisotope-containing material, MgO, a source of phosphate, and optionally, a reducing agent, in water at a temperature of less than 100.degree. C. to form a slurry; curing the slurry to form a solid intermediate CBPC article comprising the radioisotope therefrom; comminuting the intermediate CBPC article, mixing the comminuted material with glass frits, and heating the mixture at a temperature in the range of about 900 to about 1500.degree. C. to form a vitrified CBPC article comprising the radioisotope immobilized therein.

  8. Chemically durable phosphate glasses and a method for their preparation

    Science.gov (United States)

    Day, D.E.; Wilder, J.A. Jr.

    The chemical durability of alkali phosphate glasses is improved by incorporation of up to 23 weight percent of nitrogen. A typical phosphate glass contains: 10 to 60 mole % of Li/sub 2/O, Na/sub 2/O or K/sub 2/O; 5 to 40 mole % of BaO or CaO; 0 to 1 to 10 mole % of Al/sub 2/O/sub 3/; and 40 to 70 mole % of P/sub 2/O/sub 5/. Nitrides, such as AlN, are the favored additives.

  9. The role of polycarboxylic acids in calcium phosphate mineralization.

    Science.gov (United States)

    Tsortos, Achilles; Nancollas, George H

    2002-06-01

    The role of two polyelectrolytes, poly-L-glutamate and poly-L-aspartate, in the growth of calcium phosphate crystal phases, has been investigated at constant supersaturation. Both molecules are strong inhibitors of HAP growth when present in the solution phase but also act as hydroxyapatite and (octacalcium phosphate)-like crystal nucleators when adsorbed on germanium surfaces. The structure of the polymers in solution is presented and various adsorption models are analyzed. A "train-loop" structure of these long, flexible chain polymers on the crystal surface is consistent with all the adsorption (experimental and theoretical), inhibition, and electrophoretic mobility results. PMID:16290647

  10. Calcium-phosphate-osteopontin particles for caries control

    DEFF Research Database (Denmark)

    Schlafer, Sebastian

    Oftentimes caries lesions develop in protected sites that are difficult to access by self-performed mechanical tooth cleaning. At present, there is a growing interest in chemical adjuncts to mechanical procedures of oral hygiene that aim at biofilm control rather than biofilm eradication. Calcium...... drops to 6 or below and release buffering phosphate ions that stabilize biofilm pH above the critical level for enamel dissolution. With that twofold approach, calcium-phosphate-osteopontin particles may make a relevant contribution to clinical caries control....

  11. Lanthanide carbonate-phosphate complexes of different ligands

    International Nuclear Information System (INIS)

    Previously undescribed carbonate-phosphate complexes of lanthanides (Ln) have been derived. Their optical and luminescent properties have been stUdied. It is shown that the lanthanide ions may form in solutions highly charged anions preferably corresponding to formulas: [NdCO3(PO4)3]8-, [HoCO3(PO4)3]8- and [Er(CO3)2(PO4)]10-. The stability constants (Ksub(st)) of the resulting heteroligand complexes have been determined. A new version of the luminescent method of determining the composition of carbonate-phosphate complexes of Eu is suggested

  12. A study of the inhibiton of copper corrosion by triethyl phosphate and triphenyl phosphate self-assembled monolayers

    Directory of Open Access Journals (Sweden)

    HOUYI MA

    2006-02-01

    Full Text Available Two kinds of phosphates, triethyl phosphate (TEP and triphenyl phosphate (TPP, were used to form self-assembled monolayers for the inhibition of the corrosion of copper in 0.2 mol dm–3 NaCl solution. Electrochemical impedance spectroscopy (EIS was applied to investigate the inhibition effects. The results showed that their inhibition ability first increased with increasing immersion time in ethanolic solutions of the corresponding compounds. However, when the immersion time was increased over some critical point, the inhibition effect decreased. For the same immersion time, the inhibition effect of the TPP monolayer was more pronounced than that of the TEP monolayer. Thus, ab initio calculations were used to interpret the relationship between the inhibition effects and the structures of the compounds.

  13. Nano zinc phosphate coatings for enhanced corrosion resistance of mild steel

    International Nuclear Information System (INIS)

    Highlights: • Nano zinc phosphate coating on mild steel was developed. • Nano zinc phosphate coatings on mild steel showed enhanced corrosion resistance. • The nano ZnO increases the number of nucleating sites for phosphating. • Faster attainment of steady state during nano zinc phosphating. - Abstract: Nano crystalline zinc phosphate coatings were developed on mild steel surface using nano zinc oxide particles. The chemical composition and morphology of the coatings were analyzed by X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The particles size of the nano zinc phosphate coating developed was also characterized by TEM analysis. Potentiodynamic polarization and electrochemical impedance studies were carried out in 3.5% NaCl solution. Significant variations in the coating weight, morphology and corrosion resistance were observed as nano ZnO concentrations were varied from 0.25 to 2 g/L in the phosphating baths. The results showed that nano ZnO particles in the phosphating solution yielded phosphate coatings of higher coating weight, greater surface coverage and enhanced corrosion resistance than the normal zinc phosphate coatings (developed using normal ZnO particles in the phosphating baths). Better corrosion resistance was observed for coatings derived from phosphating bath containing 1.5 g/L nano ZnO. The activation effect brought about by the nano ZnO reduces the amount of accelerator (NaNO2) required for phosphating

  14. Study on phosphating treatment of aluminum alloy: role of yttrium oxide

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shenglin

    2009-01-01

    Zinc phosphate coatings formed on 6061-Al alloy, after dipping in phosphating solutions containing different amounts of Y2O3(yttrium oxide), were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD) and electrochemical measurements. Significant variations in the morphology and corrosion resistance afforded by zinc phosphate coating were especially observed as Y2O3 in phosphating solution varied from 0 to 40 mg/L. The addition of Y2O3 changed the initial potential of the interface between aluminum alloy substrate and phosphating solution and increased the number of nucleation sites. The phosphate coating thereby was less porous structure and covered the surface of aluminum alloy completely within short phosphating time. Phosphate coating was mainly composed of Zn3(PO4)2-4H2O (hopeite) and AIPO4(aluminum phosphate). Y2O3, as an additive of phosphatization, accelerated precipitation and refined the gain size of phosphate coating. The corrosion resistance of zinc phosphate coating in 3% NaCl solution was improved as shown by po-larization measurement. In the present research, the optimal amount of Y2O3 was 10-20 mg/L, and the optimal phosphating time was 600 s.

  15. Magnesium substitution in the structure of orthopedic nanoparticles: A comparison between amorphous magnesium phosphates, calcium magnesium phosphates, and hydroxyapatites

    International Nuclear Information System (INIS)

    As biocompatible materials, magnesium phosphates have received a lot of attention for orthopedic applications. During the last decade multiple studies have shown advantages for magnesium phosphate such as lack of cytotoxicity, biocompatibility, strong mechanical properties, and high biodegradability. The present study investigates the role of Mg+2 and Ca+2 ions in the structure of magnesium phosphate and calcium phosphate nanoparticles. To directly compare the effect of Mg+2 and Ca+2 ions on structure of nanoparticles and their biological behavior, three groups of nanoparticles including amorphous magnesium phosphates (AMPs) which release Mg+2, calcium magnesium phosphates (CMPs) which release Mg+2 and Ca+2, and hydroxyapatites (HAs) which release Ca+2 were studied. SEM, TEM, XRD, and FTIR were used to evaluate the morphology, crystallinity, and chemical properties of the particles. AMP particles were homogeneous nanospheres, whereas CMPs were combinations of heterogeneous nanorods and nanospheres, and HAs which contained heterogeneous nanosphere particles. Cell compatibility was monitored in all groups to determine the cytotoxicity effect of particles on studied MC3T3-E1 preosteoblasts. AMPs showed significantly higher attachment rate than the HAs after 1 day and both AMPs and CMPs showed significantly higher proliferation rate when compared to HAs after 7 days. Gene expression level of osteoblastic markers ALP, COL I, OCN, OPN, RUNX2 were monitored and they were normalized to GAPDH housekeeping gene. Beta actin expression level was monitored as the second housekeeping gene to confirm the accuracy of results. In general, AMPs and CMPs showed higher expression level of osteoblastic genes after 7 days which can further confirm the stimulating role of Mg+2 and Ca+2 ions in increasing the proliferation rate, differentiation, and mineralization of MC3T3-E1 preosteoblasts. - Highlights: • Role of Mg2+ and Ca2+ ions in proliferation, and differentiation of

  16. Efficacy of a Phosphate-Charged Soil Material in Supplying Phosphate for Plant Growth in Soilless Root Media

    OpenAIRE

    Young-Mi Oh; Paul V. Nelson; Dean L. Hesterberg; Carl E. Niedziela

    2016-01-01

    A soil material high in crystalline Fe hydrous oxides and noncrystalline Al hydrous oxides collected from the Bw horizon of a Hemcross soil containing allophane from the state of Oregon was charged with phosphate-P at rates of 0, 2.2, and 6.5 mg·g−1, added to a soilless root medium at 5% and 10% by volume, and evaluated for its potential to supply phosphate at a low, stable concentration during 14 weeks of tomato (Solanum esculentum L.) seedling growth. Incorporation of the soil material impr...

  17. Phosphate uptake kinetics for four species of submerged freshwater macrophytes measured by a 33P phosphate radioisotope technique

    DEFF Research Database (Denmark)

    Christiansen, Nina Høj; Andersen, Frede Østergaard; Jensen, Henning S.

    2016-01-01

    Phosphate (Pi) uptake kinetics were determined in shoot and root tissues for four freshwater macrophyte species, Littorella uniflora, Potamogeton perfoliatus, Myriophyllum alterniflorum and Elodea canadensis, using a radioactive 33P phosphate technique. Collection of plant material in the...... oligotrophic softwater lake, Lake Hampen, Denmark, where Pi limits macrophyte growth, enabled us to characterize and compare the Pi uptake kinetics and competitive characteristics of the four species in a low level Pi environment. The maximum Pi uptake rates (Vmax), the half saturation constants (Km) together...

  18. Functional Characterization of UDP-Glucose:Undecaprenyl-Phosphate Glucose-1-Phosphate Transferases of Escherichia coli and Caulobacter crescentus

    OpenAIRE

    Patel, Kinnari B.; Toh, Evelyn; Fernandez, Ximena B.; Hanuszkiewicz, Anna; Hardy, Gail G.; Brun, Yves V.; Bernards, Mark A.; Valvano, Miguel A.

    2012-01-01

    Escherichia coli K-12 WcaJ and the Caulobacter crescentus HfsE, PssY, and PssZ enzymes are predicted to initiate the synthesis of colanic acid (CA) capsule and holdfast polysaccharide, respectively. These proteins belong to a prokaryotic family of membrane enzymes that catalyze the formation of a phosphoanhydride bond joining a hexose-1-phosphate with undecaprenyl phosphate (Und-P). In this study, in vivo complementation assays of an E. coli K-12 wcaJ mutant demonstrated that WcaJ and PssY ca...

  19. Radio phosphorus kinetics in the blood of sheep supplemented with dicalcium phosphate, mono ammonium phosphate, triple superphosphate and Tapira rock phosphate

    International Nuclear Information System (INIS)

    With the aim to study the kinetics of radio phosphorus (32 P) in the blood of animals supplemented with dicalcium phosphate (BIC), mono ammonium phosphate (MAP), triple superphosphate (SPT) and Tapira rock phosphate (TAP), 32 male sheep were kept in metabolic cages at the Animal Science Section / CENA - USP. Plasma was obtained by centrifugation and the specific activity, rate of disappearance and half life of 32 P in plasma were determined. In the red blood cells were determined the uptake rate of the radioisotope, the rate of disappearance and half life of 32 P up taken. It was observed a statistical significant difference (p32 P in the plasma and erythrocytes. The specific activity and half life of 32 P in the plasma were statistically different (p<0,10) among sheep receiving the different phosphorus sources; the same was observed in respect to the red blood cells. It was concluded that the supplemented phosphorus source given in the diet of sheep may affect the kinetics of the radio phosphorus in the blood after been intravenously injected. (author)

  20. Phosphate DIstribution and Movement in Soil—Root Interface Zone:Ⅲ.Dynamics

    Institute of Scientific and Technical Information of China (English)

    XUMING-GANG; ZHANGYI-PING; 等

    1995-01-01

    The depletion rate of phosphate in the soil-root interface zone increased along with growth and phosphate uptske of wheat or maize,which indicated that the phosphate distribution in soil near the root surface agreed well with the phosphate movement in rhizosphere and phosphate uptake by plant,The relative accumulation zone of phosphate within 0.5mm apart from the root surface developed at the 15th day or so after cultivating wheat or maize since the root phosphate secretion increased gradually in this stage.The phosphate distribution in the soil-root interface zone against the growing time(t)and the distance from the root plane(x) could be described by the non-linear regression equation with the third powers of x and t.

  1. Dynamics and diversity of phosphate mineralizing bacteria in the coral reefs of Gulf of Mannar

    Digital Repository Service at National Institute of Oceanography (India)

    Kannapiran, E.; Ravindran, J.

    Phosphatase Producing Bacteria (PPB) and Inorganic Phosphate Solubilizing Bacteria (IPSB) are important to reef nutrition. These microbes and phosphate concentration play a significant role in the productivity of coral reef ecosystems. A study...

  2. The Path of Carbon in Photosynthesis XIX. The Identification of Sucrose Phosphate in Sugar Beet Leaves

    Science.gov (United States)

    Buchanan, J. G.

    1952-09-01

    The recognition and characterization of a sucrose phosphate as an intermediate in sucrose by synthesis by green plants is described. A tentative structure for this phosphate is proposed and its mode of formation suggested.

  3. Phosphates nanoparticles doped with zinc and manganese for sunscreens

    International Nuclear Information System (INIS)

    The crescent number of skin cancer worldwide gives impulse to the development of sunscreen that can both prevent skin cancer and also permit gradual tanning. In this work, the synthesis of hydroxyapatite and tricalcium phosphate nanocrystalline powders was investigated in order to obtain materials with optical properties and appropriate size for sunscreen. Pure, Zn2+-doped and Mn2+-doped hydroxyapatite (HAP) and tricalcium phosphate (β-TCP) were produced by the wet precipitation process using diammonium phosphate, calcium nitrate, ammonium hydroxide, zinc nitrate and manganese nitrate as reagents. The pure and doped HAP precipitates were calcined at 500 deg. C for 1 h, while the β-TCP (pure and doped) were calcined at 800 deg. C for 2 h. The powder samples were characterized by X-ray diffraction (XRD), energy dispersive X-ray fluorescence (EDX), atomic force microscopy (AFM) and ultraviolet (UV)-vis spectroscopy. XRD and EDX showed the formation of the expected materials (HAP and β-TCP) without toxic components. AFM micrographs showed aggregated ellipsoidal particles with dimensions smaller than 120 nm. Optical absorption spectra showed that the calcium phosphate produced in this work absorbs in the UV region. The obtained materials presented structural, morphological and optical properties that allow their use as the active centers in sunscreens.

  4. Phosphate Remediation and Recovery using Iron Oxide-based Adsorbents

    Science.gov (United States)

    E33-modified sorbents for the removal of phosphate from lake water was investigated in this study. E33-modified sorbents were synthesized by coating with manganese and nanoparticles. Characterization was done by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-...

  5. The apolipoprotein m-sphingosine-1-phosphate axis

    DEFF Research Database (Denmark)

    Arkensteijn, Bas W C; Berbée, Jimmy F P; Rensen, Patrick C N;

    2013-01-01

    identified as a carrier of the bioactive lipid sphingosine-1-phosphate (S1P). S1P activates five different G-protein-coupled receptors, known as the S1P-receptors 1-5 and, hence, affects a wide range of biological processes, such as lymphocyte trafficking, angiogenesis, wound repair and even virus...

  6. Cellular response of Campylobacter jejuni to trisodium phosphate

    DEFF Research Database (Denmark)

    Riedel, Charlotte Tandrup; Cohn, M. T.; Stabler, R. A.;

    2012-01-01

    The highly alkaline compound trisodium phosphate (TSP) is used as an intervention to reduce the load of Campylobacter on poultry meat in U.S. poultry slaughter plants. The aim of the present study was to investigate the cellular responses of Campylobacter jejuni NCTC11168 when exposed to sublethal...

  7. Research of inhibitor properties of the modified polymeric phosphates

    Directory of Open Access Journals (Sweden)

    A. Rakhova

    2012-03-01

    Full Text Available Diversity of structures and properties of the functional dependence on the composition of polimernofosfatov allows their use as effective inhibitors of corrosion of steel. In this connection, systematic studies of the relationship between structure, composition and effectiveness of the protective phosphate inhibitory action.

  8. Calcium phosphate bioceramics prepared from wet chemically precipitated powders

    Directory of Open Access Journals (Sweden)

    Kristine Salma

    2010-03-01

    Full Text Available In this work calcium phosphates were synthesized by modified wet chemical precipitation route. Contrary to the conventional chemical precipitation route calcium hydroxide was homogenized with planetary mill. Milling calcium oxide and water in planetary ball mill as a first step of synthesis provides a highly dispersed calcium hydroxide suspension. The aim of this work was to study the influence of main processing parameters of wet chemical precipitation synthesis product and to control the morphology, phase and functional group composition and, consequently, thermal stability and microstructure of calcium phosphate bioceramics after thermal treatment. The results showed that it is possible to obtain calcium phosphates with different and reproducible phase compositions after thermal processing (hydroxyapatite [HAp], β-tricalcium phosphate [β-TCP] and HAp/β-TCP by modified wet-chemical precipitation route. The β-TCP phase content in sintered bioceramics samples is found to be highly dependent on the changes in technological parameters and it can be controlled with ending pH, synthesis temperature and thermal treatment. Pure, crystalline and highly thermally stable (up to 1300°C HAp bioceramics with homogenous grainy microstructure, grain size up to 200–250 nm and high open porosity can be successfully obtained by powder synthesized at elevated synthesis temperature of 70°C and stabilizing ending pH at 9.

  9. Adsorption of Phosphate on Goethite: An Undergraduate Research Laboratory Project

    Science.gov (United States)

    Tribe, Lorena; Barja, Beatriz C.

    2004-01-01

    A laboratory experiment on the adsorption of phosphate on goethite is presented, which also includes discussion on surface properties, interfaces, acid-base equilibrium, molecular structure and solid state chemistry. It was seen that many students were able to produce qualitatively correct results for a complex system of real interest and they…

  10. Synthesis and characterization of zirconium-doped calcium phosphate biomaterial

    International Nuclear Information System (INIS)

    A new synthesis route for the production of calcium phosphate biomaterial was developed by using organic di-(2-ethylhexyl) phosphoric acid (DEHPA) mixed with calcium hydroxide slurry. Unlike the conventional involving chemical precipitation process this new method involves a sol-gel process. Another advantage of this method is the starting material DEHPA can form strong bonding with many elements including zirconium and rare earths. This makes it suitable to be used as drug delivery material especially those involving bone related disease. It also improves the biomaterial strength with the presence of zirconium oxide phase. From XRD analysis, the result shows the present of HA, α-TCP and β-TCP. The addition of different rare elements on to the calcium phosphate will varies the amount of these three phases. SEM analysis was also performed to study the morphology of the calcium phosphate material. The presence of the rare earths on to the calcium phosphate was established by using the EDS technique. (Author)

  11. RPL in alpha particle irradiated Ag+-doped phosphate glass

    International Nuclear Information System (INIS)

    The objective of this study is to investigate the emission mechanism of radiophotoluminescence (RPL) in the Ag+-doped phosphate glass (glass dosimeter), which is now used as individual radiation dosimeter, because the emission mechanism of RPL in glass dosimeter has been not fully understood. We have investigated the assignments and characteristics of the X-ray induced color centers in the Ag+-doped phosphate glass up to now (Miyamoto et al., 2010). Optical properties such as optical absorption spectra related with alpha-particles and X-rays irradiation were measured for commercially available glass dosimeter. In this study optical properties such as optical absorption spectrum as a function of alpha-particles and X-rays irradiation were measured for commercially available glass dosimeter. Comparison of the RPL in Ag+-doped phosphate glass irradiated with alpha-particles and X-rays is discussed. - Highlights: • A Yellow and blue emission are included in the RPL of Ag+-doped phosphate glass. • The ratio of yellow and blue emission was different between alpha and X-ray irradiation. • RPL emission intensity increased in an atmosphere below room temperature

  12. Polyfluorinated alkyl phosphate ester surfactants - current knowledge and knowledge gaps

    DEFF Research Database (Denmark)

    Taxvig, Camilla; Rosenmai, Anna Kjerstine; Vinggaard, Anne Marie

    2014-01-01

    information on fluorochemicals. Polyfluorinated alkyl phosphate ester surfactants (PAPs) belong to the group of polyfluorinated alkyl surfactants. They have been detected in indoor dust and are widely used in food-contact materials, from which they have the ability to migrate into food. Toxicological data on...

  13. Catalytic Kinetic Spectrophotometric Method for Determination of Phosphate Ion

    Institute of Scientific and Technical Information of China (English)

    MITIC,Snezana; ZIVANOVIC,Valentina; OBRADOVIC,Mirjana; TOSIC,Snezana; PAVLOVIC,Aleksandra

    2007-01-01

    The kinetic method for the determination of phosphate microamounts was described.The developed method is based on catalytic effect of phosphate on sodium pyrogallol-5-sulphonate(PS)by dissolved oxygen.The reaction was followed spectrophotometrically by measuring the rate of change in the values of the absorbance of the oxidation product at 437 nm.The optimum reaction conditions are PS(0.44×10-3 mol·L-1)and HClO4(3.6×10-6mol·L-1)at 25℃.Following this procedure,phosphate can be determined with a linear calibration graph up to 0.23 μg·mL-1.The interference effect of several species was also investigated and it was found that the most common cations and anions did not interfere with the determination.The developed procedure was successfully applied to the determination of phosphate in natural waters and soil.

  14. Calcium and phosphate homeostasis: concerted interplay of new regulators.

    NARCIS (Netherlands)

    Renkema, K.Y.R.; Alexander, R.T.; Bindels, R.J.M.; Hoenderop, J.G.J.

    2008-01-01

    Calcium (Ca(2+)) and phosphate (P(i)) are essential to many vital physiological processes. Consequently the maintenance of Ca(2+) and P(i) homeostasis is essential to a healthy existence. This occurs through the concerted action of intestinal, renal, and skeletal regulatory mechanisms. Ca(2+) and P(

  15. Immobilization of fission products in phosphate ceramic waste forms

    International Nuclear Information System (INIS)

    The goal of this project is to develop and demonstrate the feasibility of a novel low-temperature solidification/stabilization (S/S) technology for immobilizing waste streams containing fission products such as cesium, strontium, and technetium in a chemically bonded phosphate ceramic. This technology can immobilize partitioned tank wastes and decontaminate waste streams containing volatile fission products

  16. Biomimetic calcium phosphate coatings on recombinant spider silk fibres

    Energy Technology Data Exchange (ETDEWEB)

    Yang Liang; Habibovic, Pamela; Van Blitterswijk, Clemens A [Department of Tissue Regeneration, University of Twente, PO Box 217, 7500 AE Enschede (Netherlands); Hedhammar, My; Johansson, Jan [Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, the Biomedical Centre, Box 575, 751 23 Uppsala (Sweden); Blom, Tobias; Leifer, Klaus [Department of Engineering Sciences, Uppsala University, Box 534, S-751 21 Uppsala (Sweden)

    2010-08-01

    Calcium phosphate ceramic coatings, applied on surfaces of metallic and polymeric biomaterials, can improve their performance in bone repair and regeneration. Spider silk is biocompatible, strong and elastic, and hence an attractive biomaterial for applications in connective tissue repair. Recently, artificial spider silk, with mechanical and structural characteristics similar to those of native spider silk, has been produced from recombinant minispidroins. In the present study, supersaturated simulated body fluid was used to deposit calcium phosphate coatings on recombinant spider silk fibres. The mineralization process was followed in time using scanning electron microscopy equipped with an energy dispersive x-ray (EDX) detector and Raman spectroscope. Focused ion beam technology was used to produce a cross section of a coated fibre, which was further analysed by EDX. Preliminary in vitro experiments using a culture of bone marrow-derived human mesenchymal stem cells (hMSCs) on coated fibres were also performed. This study showed that recombinant spider silk fibres were successfully coated with a homogeneous and thick crystalline calcium phosphate layer. In the course of the mineralization process from modified simulated body fluid, sodium chloride crystals were first deposited on the silk surface, followed by the deposition of a calcium phosphate layer. The coated silk fibres supported the attachment and growth of hMSCs.

  17. Working levels in the phosphate fertilizer plant in Croatia

    International Nuclear Information System (INIS)

    Phosphate rocks used for production of phosphate fertilizers contain various concentrations of radioactive elements. The principal radionuclides are from the 238U and 3Th decay series and 40K. In classic phosphoric acid process, concentrations of uranium and radium were disrupted, with uranium appearing primarily in the finished product (fertilizer) and radium favoring the gypsum. Since the activity mass concentrations of uranium and radium in phosphate fertilizers are several times higher than in average soil, they constitute an additional source of radiation exposure for workers and members of public. One of the source of exposure to the population in the vicinity of phosphate fertilizer plant (PFP) results from inhalation of radon daughters. For the reason the investigations of the hazards were undertaken in the fertilizer plant in Croatia, and the radon daughter concentrations in different atmospheres are discussed in this paper. Working levels were measured as 'grab samples' at several stations on-site and off-site of the PFP. The average mean values of working levels are presented. (author)

  18. Novel inhibitors of mitochondrial sn-glycerol 3-phosphate dehydrogenase.

    Directory of Open Access Journals (Sweden)

    Adam L Orr

    Full Text Available Mitochondrial sn-glycerol 3-phosphate dehydrogenase (mGPDH is a ubiquinone-linked enzyme in the mitochondrial inner membrane best characterized as part of the glycerol phosphate shuttle that transfers reducing equivalents from cytosolic NADH into the mitochondrial electron transport chain. Despite the widespread expression of mGPDH and the availability of mGPDH-null mice, the physiological role of this enzyme remains poorly defined in many tissues, likely because of compensatory pathways for cytosolic regeneration of NAD⁺ and mechanisms for glycerol phosphate metabolism. Here we describe a novel class of cell-permeant small-molecule inhibitors of mGPDH (iGP discovered through small-molecule screening. Structure-activity analysis identified a core benzimidazole-phenyl-succinamide structure as being essential to inhibition of mGPDH while modifications to the benzimidazole ring system modulated both potency and off-target effects. Live-cell imaging provided evidence that iGPs penetrate cellular membranes. Two compounds (iGP-1 and iGP-5 were characterized further to determine potency and selectivity and found to be mixed inhibitors with IC₅₀ and K(i values between ∼1-15 µM. These novel mGPDH inhibitors are unique tools to investigate the role of glycerol 3-phosphate metabolism in both isolated and intact systems.

  19. Rapid degradation of zinc oxide nanoparticles by phosphate ions

    Directory of Open Access Journals (Sweden)

    Rudolf Herrmann

    2014-11-01

    Full Text Available Zinc oxide nanoparticles are highly sensitive towards phosphate ions even at pH 7. Buffer solutions and cell culture media containing phosphate ions are able to destroy ZnO nanoparticles within a time span from less than one hour to one day. The driving force of the reaction is the formation of zinc phosphate of very low solubility. The morphology of the zinc oxide particles has only a minor influence on the kinetics of this reaction. Surface properties related to different production methods and the presence and absence of labelling with a perylene fluorescent dye are more important. Particles prepared under acidic conditions are more resistant than those obtained in basic or neutral reaction medium. Surprisingly, the presence of a SiO2 coating does not impede the degradation of the ZnO core. In contrast to phosphate ions, β-glycerophosphate does not damage the ZnO nanoparticles. These findings should be taken into account when assessing the biological effects or the toxicology of zinc oxide nanoparticles.

  20. Investigations on sodium tin phosphate and tin pyrophosphate glasses

    OpenAIRE

    Sobha, KC; Rao, KJ

    1995-01-01

    Glasses of the alkali tin phosphate system have been investigated. The infrared absorption and fluorescence spectra of the glasses have been examined. It is found that tin is present in both + 2 and + 4 oxidation states. Also tin ions occupy four- or six-coordinated sites in the glass.

  1. Alkylation of quinolines with trialkyl phosphates Pt. 3

    International Nuclear Information System (INIS)

    Intermolecular direct methyl transfer from the O-methyl group of N-methyl-4-methoxy-quinolinium quaternary salt to the ring nitrogen atom of 4-methoxyquinoline formed as intermediates in the alkylation reaction of 4-quinolone with trimethyl phosphate to N-methyl-4-quinolone was established by using tracer techniques. (author)

  2. Alkylation of quinolines with trialkyl phosphates Pt. 3. Isotopic studies

    Energy Technology Data Exchange (ETDEWEB)

    Dutka, F.; Marton, A.F.; Koemives, T. (Magyar Tudomanyos Akademia Koezponti Kemiai Kutato Intezete, Budapest); Frank, J. (CHINOIN Gyogyszer es Vegyeszeti Termekek Gyara Rt., Budapest (Hungary))

    1981-10-03

    Intermolecular direct methyl transfer from the O-methyl group of N-methyl-4-methoxy-quinolinium quaternary salt to the ring nitrogen atom of 4-methoxyquinoline formed as intermediates in the alkylation reaction of 4-quinolone with trimethyl phosphate to N-methyl-4-quinolone was established by using tracer techniques.

  3. RELEASE PAPER: CAN PHOSPHATE ESTERS BE AN ALTERNATIVE TO SILICONE?

    Directory of Open Access Journals (Sweden)

    Dan Belosinschi,

    2012-01-01

    Full Text Available Release paper is a special paper grade with one or both sides coated with non-sticking materials. Silicone is currently the only material used to produce release paper at the industrial level. Its remarkable properties and availability ensure product quality and sustainability of the industrial production. Meanwhile, the stability of silicone polymers raises serious environmental problems in terms of paper substrate recyclability. Studies are currently under way to evaluate the ability of phosphate esters as a new class of compounds capable of developing non-adhesive surface properties. This paper presents initial attempts to coat the paper with phosphate esters and to assess phosphate ester / fibrous substrate and phosphate ester / adhesive interactions. The results show that this class of compounds exhibits non-adhesive properties and, when coated on paper under certain conditions, can lead to a non-sticking surface. Despite the fact that there is a long way to achieve ester anchoring to surface fibers and to control the peeling force from an adhesive tape, preliminary results are encouraging.

  4. Mechanical properties of porous, electrosprayed calcium phosphate coatings

    NARCIS (Netherlands)

    Leeuwenburgh, S.C.G.; Wolke, J.G.C.; Lommen, L.; Pooters, T.; Schoonman, J.; Jansen, J.A.

    2006-01-01

    Mechanical properties of calcium phosphate coatings (CaP), deposited using the electrostatic spray deposition (ESD) technique, have been characterized using a range of analytical techniques, including tensile testing (ASTM C633), fatigue testing (ASTM E855), and scratch testing using blunt and sharp

  5. Biomimetic calcium phosphate coatings on recombinant spider silk fibres

    International Nuclear Information System (INIS)

    Calcium phosphate ceramic coatings, applied on surfaces of metallic and polymeric biomaterials, can improve their performance in bone repair and regeneration. Spider silk is biocompatible, strong and elastic, and hence an attractive biomaterial for applications in connective tissue repair. Recently, artificial spider silk, with mechanical and structural characteristics similar to those of native spider silk, has been produced from recombinant minispidroins. In the present study, supersaturated simulated body fluid was used to deposit calcium phosphate coatings on recombinant spider silk fibres. The mineralization process was followed in time using scanning electron microscopy equipped with an energy dispersive x-ray (EDX) detector and Raman spectroscope. Focused ion beam technology was used to produce a cross section of a coated fibre, which was further analysed by EDX. Preliminary in vitro experiments using a culture of bone marrow-derived human mesenchymal stem cells (hMSCs) on coated fibres were also performed. This study showed that recombinant spider silk fibres were successfully coated with a homogeneous and thick crystalline calcium phosphate layer. In the course of the mineralization process from modified simulated body fluid, sodium chloride crystals were first deposited on the silk surface, followed by the deposition of a calcium phosphate layer. The coated silk fibres supported the attachment and growth of hMSCs.

  6. Immobilization of fission products in phosphate ceramic waste forms

    International Nuclear Information System (INIS)

    Argonne National Laboratory (ANL) is developing chemically bonded phosphate ceramics (CBPCs) to treat low-level mixed wastes, particularly those containing volatiles and pyrophorics that cannot be treated by conventional thermal processes. This work was begun under ANL''s Laboratory Directed Research and Development funds, followed by further development with support from EM-50''s Mixed Waste Focus Area

  7. Bond strength of plasma sprayed ceramic coatings on phosphate steels

    Czech Academy of Sciences Publication Activity Database

    Pokorný, P.; Mastný, L.; Sýkora, V.; Pala, Zdeněk; Brožek, Vlastimil

    2015-01-01

    Roč. 54, č. 2 (2015), s. 411-414. ISSN 0543-5846 R&D Projects: GA ČR(CZ) GAP108/12/1872 Institutional support: RVO:61389021 Keywords : phosphating * plasma spraying * ceramic coatings * corrosion * bond strength Subject RIV: CA - Inorganic Chemistry Impact factor: 0.959, year: 2014

  8. Phosphate diester cleavage promoted by the novel artificial biomimetic agent

    Czech Academy of Sciences Publication Activity Database

    Bím, Daniel; Rulíšek, Lubomír; Hodačová, J.

    Praha: Czech Chemical Society, 2014. s. 51. [Liblice 2014. Advances in Organic, Bioorganic and Pharmaceutical Chemistry /49./. 07.11.2014-09.11.2014, Lázně Bělohrad] Institutional support: RVO:61388963 Keywords : phosphate diesters * bond cleavage Subject RIV: CF - Physical ; Theoretical Chemistry

  9. Casein Phosphopeptide-Amorphous Calcium Phosphate Nanocomplexes: A Structural Model.

    Science.gov (United States)

    Cross, Keith J; Huq, N Laila; Reynolds, Eric C

    2016-08-01

    Tryptic digestion of the calcium-sensitive caseins yields casein phosphopeptides (CPP) that contain clusters of phosphorylated seryl residues. The CPP stabilize calcium and phosphate ions through the formation of complexes. The calcium phosphate in these complexes is biologically available for intestinal absorption and remineralization of subsurface lesions in tooth enamel. We have studied the structure of the complexes formed by the CPP with calcium phosphate using a variety of nuclear magnetic resonance (NMR) techniques. Translational diffusion measurements indicated that the β-CN(1-25)-ACP nanocomplex has a hydrodynamic radius of 1.526 ± 0.044 nm at pH 6.0, which increases to 1.923 ± 0.082 nm at pH 9.0. (1)H NMR spectra were well resolved, and (3)JH(N)-H(α) measurements ranged from a low of 5.5 Hz to a high of 8.1 Hz. Total correlation spectroscopy and nuclear Overhauser effect spectroscopy spectra were acquired and sequentially assigned. Experiments described in this paper have allowed the development of a structural model of the β-CN(1-25)-amorphous calcium phosphate nanocomplex. PMID:27434168

  10. Radiological Evaluation of phosphate fertilizers used in Tunisia

    International Nuclear Information System (INIS)

    The need of control of natural radioactivity in the environment and the radiological impact of the use of chemical fertilizers has led us in this work to measure the natural radioactivity of the phosphate fertilizers in Tunisia. The distribution of various radionuclides during their manufacturing process of fertilizers is also part of this work.

  11. Extraction of cadmium thiocyanate complex by tributyl phosphate in benzene

    Energy Technology Data Exchange (ETDEWEB)

    Singh, D.; Tandon, S.N. (Roorkee Univ. (India). Dept. of Chemistry)

    1981-09-01

    The extraction of cadmium thiocyanate complex has been studied in benzene solution of tri-n-butyl phosphate. The species extracted is shown to be Cd(SCN)X.4TBP, where X is a common anion. The extraction data have also been used for achieving some metal ion separation.

  12. Prediction of the Setting Properties of Calcium Phosphate Bone Cement

    Directory of Open Access Journals (Sweden)

    Seyed Mahmud Rabiee

    2012-01-01

    Full Text Available Setting properties of bone substitutes are improved using an injectable system. The injectable bone graft substitutes can be molded to the shape of the bone cavity and set in situ when injected. Such system is useful for surgical operation. The powder part of the injectable bone cement is included of β-tricalcium phosphate, calcium carbonate, and dicalcium phosphate and the liquid part contains poly ethylene glycol solution with different concentrations. In this way, prediction of the mechanical properties, setting times, and injectability helps to optimize the calcium phosphate bone cement properties. The objective of this study is development of three different adaptive neurofuzzy inference systems (ANFISs for estimation of compression strength, setting time, and injectability using the data generated based on experimental observations. The input parameters of models are polyethylene glycol percent and liquid/powder ratio. Comparison of the predicted values and measured data indicates that the ANFIS model has an acceptable performance to the estimation of calcium phosphate bone cement properties.

  13. Prediction of the setting properties of calcium phosphate bone cement.

    Science.gov (United States)

    Rabiee, Seyed Mahmud; Baseri, Hamid

    2012-01-01

    Setting properties of bone substitutes are improved using an injectable system. The injectable bone graft substitutes can be molded to the shape of the bone cavity and set in situ when injected. Such system is useful for surgical operation. The powder part of the injectable bone cement is included of β-tricalcium phosphate, calcium carbonate, and dicalcium phosphate and the liquid part contains poly ethylene glycol solution with different concentrations. In this way, prediction of the mechanical properties, setting times, and injectability helps to optimize the calcium phosphate bone cement properties. The objective of this study is development of three different adaptive neurofuzzy inference systems (ANFISs) for estimation of compression strength, setting time, and injectability using the data generated based on experimental observations. The input parameters of models are polyethylene glycol percent and liquid/powder ratio. Comparison of the predicted values and measured data indicates that the ANFIS model has an acceptable performance to the estimation of calcium phosphate bone cement properties. PMID:22919372

  14. Synthesis of Nano-sized Boehmites for Optimum Phosphate Sorption

    DEFF Research Database (Denmark)

    Watanabe, Yujiro; Kasama, Takeshi; Fukushi, Keisuke;

    2011-01-01

    Nano-sized boehmites with different crystallinity were synthesized at the temperature range of 25 to 200°C in order to produce phosphate absorbents with high capacity. The physicochemical property of boehmites was depended on the synthesis temperature: the particle size was increased and the...

  15. Ribose 5-Phosphate Isomerase Investigations for the Undergraduate Biochemistry Laboratory

    Science.gov (United States)

    Jewett, Kathy; Sandwick, Roger K.

    2011-01-01

    The enzyme ribose 5-phosphate isomerase (RpiA) has many features that make it attractive as a focal point of a semester-long, advanced biochemistry laboratory for undergraduate students. The protein can easily and inexpensively be isolated from spinach using traditional purification techniques. Characterization of RpiA enzyme activity can be…

  16. Synthesis, characterization and photocatalytic reactions of phosphated mesoporous titania

    Indian Academy of Sciences (India)

    Pallabi Goswami; Jatindra Nath Ganguli

    2012-10-01

    Mesoporous titania nanoparticles with a well-definedmesostructure was prepared by hydrothermal process, using nonionic triblock copolymer P123 as surfactant template, modified with phosphoric acid and followed by calcination at 600°C. The sol–gel titania was modified by in situ phosphorylation using phosphoric acid and thereby incorporating phosphorous directly into the framework of TiO2. The resulting materials were characterized by XRD, SEM, TEM, nitrogen adsorption, TGA and DRS. It was found that the structural and optical properties of titania samples are strongly influenced by their phosphate modification. In case of calcined samples a positive effect on the specific surface area for the in situ phosphated sample was found. Mesoporous structure of phosphated titania did not collapse even after calcination at 600°C. The enhanced photocatalytic activity of the synthesized phosphate nanomaterials were evaluated through a study of the decomposition of fluorescein under UV light excitation and compared with undoped titania nanomaterial as well as with commercial titania.

  17. Grafting cyclodextrins to calcium phosphate ceramics for biomedical applications

    DEFF Research Database (Denmark)

    Jacobsen, P.A.L.; Nielsen, J.L.; Juhl, M.V.;

    2012-01-01

    The grafting of hydroxyapatite/beta-tricalcium phosphate with β-cyclodextrin was achieved using a two step reaction with (3-glycidyloxypropyl)trimethoxysilane as a linker. Firstly, the silane group was brought to react with the hydroxyl groups at the surface of the hydroxyapatite/beta-tricalcium ...

  18. 21 CFR 184.1141a - Ammonium phosphate, monobasic.

    Science.gov (United States)

    2010-04-01

    ... phosphoric acid at a pH below 5.8. (b) The ingredient meets the specifications of the Food Chemicals Codex... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ammonium phosphate, monobasic. 184.1141a Section 184.1141a Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN...

  19. 21 CFR 184.1141b - Ammonium phosphate, dibasic.

    Science.gov (United States)

    2010-04-01

    ... acid at a pH above 5.8. (b) The ingredient meets the specifications of the Food Chemicals Codex, 3d Ed... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ammonium phosphate, dibasic. 184.1141b Section 184.1141b Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

  20. Immobilization of fission products in phosphate ceramic waste forms

    Energy Technology Data Exchange (ETDEWEB)

    Singh, D. [Argonne National Lab., IL (United States)

    1996-10-01

    The goal of this project is to develop and demonstrate the feasibility of a novel low-temperature solidification/stabilization (S/S) technology for immobilizing waste streams containing fission products such as cesium, strontium, and technetium in a chemically bonded phosphate ceramic. This technology can immobilize partitioned tank wastes and decontaminate waste streams containing volatile fission products.

  1. Corrosion of alloy 22 in phosphate and chloride containing solutions

    International Nuclear Information System (INIS)

    Alloy C-22 is a Ni-based alloy (22% Cr, 13% Mo, 3% W y 3% Fe in weight per cent) that exhibits an excellent uniform and localized corrosion resistance due to its protective passive film. It was designed to resist the most aggressive environments for industrial applications. Alloy 22 is one of the candidates to be considered for the outer shell of the canister that would contain high level radioactive nuclear wastes. The effect of phosphate ion in chloride containing solutions at 90 C degrees was studied under aggressive conditions were this material might be susceptible to crevice corrosion. The electrolyte solution, which consisted of 1M NaCl and different phosphate concentrations (between 10-3M and 1M), was deoxygenated by bubbling with nitrogen. Electrochemical tests, electron microscope observations (SEM) and energy dispersive spectrometer analysis (EDS) were conducted. Crevice corrosion was not detected and the comparison of the potentiodynamic polarization tests showed an increase of the passivity range in phosphate containing solutions. The passive current value was 1 μA/cm2 approximately in all the tests that were performed in this work. The differences in composition of the anodic film formed on the samples suggest that phosphate is responsible for the increase of the passivity range by incorporation to the passive film. (author)

  2. Laser performance of a new ytterbium doped phosphate laser glass

    OpenAIRE

    Griebner, U.; R. Koch; Schönnagel, H.; Jiang, S.; Myers, M J; Rhonehouse, D.; Hamlin, S.J.; Clarkson, W.A.; Hanna, D.C.

    1996-01-01

    Laser operation of a new Yb3+-doped phosphate glass with 440 mW cw output power and a slope efficiency of 49% with respect to the absorbed pump power was achieved at room temperature by pumping with a cw diode-pumped Nd:YAG laser operating at 946 nm.

  3. Osteoinduction of calcium phosphate biomaterials in small animals

    International Nuclear Information System (INIS)

    Although osteoinduction mechanism of calcium phosphate (CP) ceramics is still unclear, several essential properties have been reported, such as chemical composition, pore size and porosity, etc. In this study, calcium phosphate powder (Ca3(PO4)2, CaP, group 1), biphasic calcium phosphate ceramic powder (BCP, group 2), and intact BCP rods (group 3) were implanted into leg muscles of mice and dorsal muscles of rabbits. One month and three months after implantation, samples were harvested for biological and histological analysis. New bone tissues were observed in 10/10 samples in group 1, 3/10 samples in group 2, and 9/10 samples in group 3 at 3rd month in mice, but not in rabbits. In vitro, human mesenchymal stem cells (hMSCs) were cultured with trace CaP and BCP powder, and osteogenic differentiation was observed at day 7. Our results suggested that chemical composition is the prerequisite in osteoinduction, and pore structure would contribute to more bone formation. - Highlights: ► Intrinsic osteoinduction of calcium phosphate biomaterials was observed implanted in muscles of mice. ► Biomaterials powder also has osteoinduction property. ► Osteogenic genes and protein could be detected by RT-PCR and Western blot in implanted biomaterials. ► Osteogenic phenomenon could be observed by electron microscopy. ► The chemical composition is the prerequisite in osteoinduction, and pore structure would contribute to more bone formation

  4. Transmission spectra study of sulfate substituted potassium dihydrogen phosphate

    KAUST Repository

    LI, LIANG

    2013-04-18

    Potassium dihydrogen phosphate (KDP) crystals with different amounts of sulfate concentration were grown and the transmittance spectrum was studied. A crystal with high sulfate replacement density exhibits heavy absorption property in the ultraviolet region which confirms and agrees well with former results. © 2013 Astro Ltd.

  5. Phosphates nanoparticles doped with zinc and manganese for sunscreens

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, T.S. de, E-mail: tatiana.araujo@ifs.edu.br [Departamento de Fisica, Universidade Federal de Sergipe, Sergipe (Brazil); Instituto Federal de Ciencias e Tecnologia de Sergipe, Sergipe (Brazil); Souza, S.O. de [Departamento de Fisica, Universidade Federal de Sergipe, Sergipe (Brazil); Miyakawa, W. [Divisao de Fotonica - Instituto de Estudos Avancados, Sao Jose dos Campos (Brazil); Sousa, E.M.B. de [Centro de Desenvolvimento de Tecnologia Nuclear - CDTN/CNEN, Minas Gerais (Brazil)

    2010-12-01

    The crescent number of skin cancer worldwide gives impulse to the development of sunscreen that can both prevent skin cancer and also permit gradual tanning. In this work, the synthesis of hydroxyapatite and tricalcium phosphate nanocrystalline powders was investigated in order to obtain materials with optical properties and appropriate size for sunscreen. Pure, Zn{sup 2+}-doped and Mn{sup 2+}-doped hydroxyapatite (HAP) and tricalcium phosphate ({beta}-TCP) were produced by the wet precipitation process using diammonium phosphate, calcium nitrate, ammonium hydroxide, zinc nitrate and manganese nitrate as reagents. The pure and doped HAP precipitates were calcined at 500 deg. C for 1 h, while the {beta}-TCP (pure and doped) were calcined at 800 deg. C for 2 h. The powder samples were characterized by X-ray diffraction (XRD), energy dispersive X-ray fluorescence (EDX), atomic force microscopy (AFM) and ultraviolet (UV)-vis spectroscopy. XRD and EDX showed the formation of the expected materials (HAP and {beta}-TCP) without toxic components. AFM micrographs showed aggregated ellipsoidal particles with dimensions smaller than 120 nm. Optical absorption spectra showed that the calcium phosphate produced in this work absorbs in the UV region. The obtained materials presented structural, morphological and optical properties that allow their use as the active centers in sunscreens.

  6. Extracellular phosphate requirement for insulin action on isolated rat hepatocytes

    International Nuclear Information System (INIS)

    Isolated rat hepatocytes were prepared in Krebs-Henseleit bicarbonate (KHB) buffer, pH 7.4, by a procedure described earlier. They were centrifuged and washed twice in KHB buffer containing 0, 0.05, 0.1, 0.02, 0.05, 0.89 or 1.0 mM phosphate and were incubated at 30 degrees C in the presence of tracer 2,3-14C-succinate and 0.5 mM concentration of each of the 20 natural amino acids. Hepatocytes washed and incubated in KHB buffer containing less than 0.05 mM phosphate failed to show any insulin stimulation of 2,3-14C-succinate oxidation or protein incorporation of tracer carbons. Mitochondrial oxidation of succinate carbons was significantly lower in the medium containing less than 1.0 mM phosphate. Maximal insulin stimulatory effect was observed in the presence of 1 mM phosphate in the medium. These data indicate that a diminished insulin responsiveness in hypophosphatemic patients may be due to the insensitivity of mitochondria to insulin in the hypophosphatemic state

  7. SCALEUP OF ALUMINUM PHOSPHATE CATALYST FOR PILOT PLANT LPDMEtm RUN

    Energy Technology Data Exchange (ETDEWEB)

    Andrew W. Wang

    2002-01-01

    The Liquid Phase Dimethyl Ether (LPDME{trademark}) process converts synthesis gas to dimethyl ether in a single slurry bubble column reactor. A mixed slurry of methanol synthesis catalyst and methanol dehydration catalyst in a neutral mineral oil simultaneously synthesizes methanol from syngas and converts some of it to dimethyl ether and water. The reaction scheme is shown below: 2H{sub 2} + CO = CH{sub 3}OH; 2CH{sub 3}OH = CH{sub 3}OCH{sub 3} + H{sub 2}O; H{sub 2}O + CO = CO{sub 2} + H{sub 2}. Most of the water produced in this reaction is converted to hydrogen by reduction with carbon monoxide (water gas shift reaction). This synergy permits higher per pass conversion than methanol synthesis alone. The enhancement in conversion occurs because dehydration of the methanol circumvents the equilibrium constraint of the syngas-to-methanol step. The slurry bubble column reactor provides the necessary heat transfer capacity to handle the greater heat duty associated with high conversion. In order to improve the stability of the catalyst system, non-stoichiometric aluminum phosphate was proposed as the dehydration catalyst for the LPDME{trademark} process. This aluminum phosphate material is a proprietary catalyst. This catalyst system of a standard methanol catalyst and the aluminum phosphate provided stable process performance that met the program targets under our standard test process conditions in the laboratory. These targets are (1) an initial methanol equivalent productivity of 28 gmol/kg/hr, (2) a CO{sub 2}-free, carbon selectivity of 80% to dimethyl ether and (3) stability of both catalysts equivalent to that of the methanol catalyst in the absence of the aluminum phosphate. A pilot plant trial of the LPDME{trademark} process using the aluminum phosphate catalyst was originally planned for March 1998 at the DOE-owned, Air Products (APCI)-operated facility at LaPorte, Texas. Because the aluminum phosphate catalyst is not commercially available, we initiated a

  8. SCALEUP OF ALUMINUM PHOSPHATE CATALYST FOR PILOT PLANT LPDMEtm RUN

    Energy Technology Data Exchange (ETDEWEB)

    Andrew W. Wang

    2002-05-15

    The Liquid Phase Dimethyl Ether (LPDME{trademark}) process converts synthesis gas to dimethyl ether in a single slurry bubble column reactor. A mixed slurry of methanol synthesis catalyst and methanol dehydration catalyst in a neutral mineral oil simultaneously synthesizes methanol from syngas and converts some of it to dimethyl ether and water. The reaction scheme is: 2H{sub 2} + CO = CH{sub 3}OH 2CH{sub 3}OH = CH{sub 3}OCH{sub 3} + H{sub 2}O H{sub 2}O + CO = CO{sub 2} + H{sub 2}. Most of the water produced in this reaction is converted to hydrogen by reduction with carbon monoxide (water gas shift reaction). This synergy permits higher per pass conversion than methanol synthesis alone. The enhancement in conversion occurs because dehydration of the methanol circumvents the equilibrium constraint of the syngas-to-methanol step. The slurry bubble column reactor provides the necessary heat transfer capacity to handle the greater heat duty associated with high conversion. In order to improve the stability of the catalyst system, non-stoichiometric aluminum phosphate was proposed as the dehydration catalyst for the LPDME{trademark} process. This aluminum phosphate material is a proprietary catalyst. This catalyst system of a standard methanol catalyst and the aluminum phosphate provided stable process performance that met the program targets under our standard test process conditions in the laboratory. These targets are (1) an initial methanol equivalent productivity of 28 gmol/kg/hr, (2) a CO{sub 2}-free, carbon selectivity of 80% to dimethyl ether and (3) stability of both catalysts equivalent to that of the methanol catalyst in the absence of the aluminum phosphate. A pilot plant trial of the LPDME{trademark} process using the aluminum phosphate catalyst was originally planned for March 1998 at the DOE-owned, Air Products (APCI)-operated facility at LaPorte, Texas. Because the aluminum phosphate catalyst is not commercially available, we initiated a scaleup project

  9. Resorption Rate Tunable Bioceramic: Si, Zn-Modified Tricalcium Phosphate

    Energy Technology Data Exchange (ETDEWEB)

    Xiang Wei

    2006-08-09

    This dissertation is organized in an alternate format. Several manuscripts which have already been published or are to be submitted for publication have been included as separate chapters. Chapter 1 is a general introduction which describes the dissertation organization and introduces the human bone and ceramic materials as bone substitute. Chapter 2 is the background and literature review on dissolution behavior of calcium phosphate, and discussion of motivation for this research. Chapter 3 is a manuscript entitled ''Si,Zn-modified tricalcium phosphate: a phase composition and crystal structure study'', which was published in ''Key Engineering Materials'' [1]. Chapter 4 gives more crystal structure details by neutron powder diffraction, which identifies the position for Si and Zn substitution and explains the stabilization mechanism of the structure. A manuscript entitled ''Crystal structure analysis of Si, Zn-modified Tricalcium phosphate by Neutron Powder Diffraction'' will be submitted to Biomaterials [2]. Chapter 5 is a manuscript, entitled ''Dissolution behavior and cytotoxicity test of Si, Zn-modified tricalcium phosphate'', which is to be submitted to Biomaterials [3]. This paper discusses the additives effect on the dissolution behavior of TCP, and cytotoxicity test result is also included. Chapter 6 is the study of hydrolysis process of {alpha}-tricalcium phosphate in the simulated body fluid, and the phase development during drying process is discussed. A manuscript entitled ''Hydrolysis of {alpha}-tricalcium phosphate in simulated body fluid and phase transformation during drying process'' is to be submitted to Biomaterials [4]. Ozan Ugurlu is included as co-authors in these two papers due to his TEM contributions. Appendix A is the general introduction of the materials synthesis, crystal structure and preliminary dissolution result. A manuscript entitled

  10. NMR spectroscopic study of organic phosphate esters coprecipitated with calcite

    Science.gov (United States)

    Phillips, Brian L.; Zhang, Zelong; Kubista, Laura; Frisia, Silvia; Borsato, Andrea

    2016-06-01

    Organic phosphorus incorporated in calcite during laboratory precipitation experiments and in natural cave deposits was investigated by solid-state NMR spectroscopy. For calcite precipitated in the presence of organic phosphoesters of varying size and functionality, solid-state 31P{1H} CP/MAS NMR shows that the phosphoesters were incorporated intact into the solid. Systematic changes in the 31P NMR chemical shift of the phosphate group were observed between the solid phosphoester and that incorporated in the solid precipitate, yielding 31P NMR chemical shifts of the coprecipitates in the range of +1.8 to -2.2 ppm. These chemical shifts are distinct from that of similarly prepared calcite coprecipitated with inorganic phosphate, 3.5 ppm. Only minor changes were noted in the phosphoester 31P chemical shift anisotropy (CSA) which suggests no significant change in the local structure of the phosphate group, which is dominated by C-O-P bonding. Close spatial proximity of the organic phosphate group to calcite structural components was revealed by 31P/13C rotational echo double resonance (REDOR) experiments for coprecipitates prepared with 13C-labeled carbonate. All coprecipitates showed significant 31P dephasing effects upon 13C-irradiation, signaling atomic-scale proximity to carbonate carbon. The dephasing rate for smaller organophosphate molecules is similar to that observed for inorganic phosphate, whereas much slower dephasing was observed for larger molecules having long and/or bulky side-chains. This result suggests that small organic molecules can be tightly enclosed within the calcite structure, whereas significant structural disruption required to accommodate the larger organic molecules leads to longer phosphate-carbonate distances. Comparison of 31P NMR spectroscopic data from the synthetic coprecipitates with those from calcite moonmilk speleothems indicates that phosphorus occurs mainly as inorganic orthophosphate in the natural deposits, although small

  11. Microbial Leaching of Some Valuable Elements From Egyptian Phosphate Rock

    International Nuclear Information System (INIS)

    Four phosphate rock samples representing different phosphate mineralization modes in Egypt were selected from Abu Tartar, Nile valley and Red sea areas. Factors affecting the phosphate rock solubilization and some of the contained valuable elements by Aspergillus niger, Penicillium sp. and Pseudomonas fluorescence, were studied with especial orientation towards the completion of phosphate rock samples solubilization especially die low grade one. Effect of nitrogen source type on leaching efficiency by Aspergillus niger when two nitrogen sources on the phosphate bioleaching efficiency, it is clear that the ammonium chloride is more favorable as nitrogen source than sodium nitrate in the bioleaching of phosphate rocks. When Aspergillus niger was applied under die following conditions: 50 g/1 of sucrose as a carbon source, 0.1 N of ammonium chloride as a nitrogen source, 10 days incubation period, 0.5% solid: liquid ratio for P2O5 and 5% for U and REE and - 270 mesh of grain size. The optimum leaching of P2O5 , U and REE from phosphate rock samples reached (23.27%, 17.4%, 11.4%, respectively), while at -60 mesh they reached to 16.58%, 28.9%, 30.2% respectively. The optimum conditions for the maximal leaching efficiencies of P2O5 , U and REE when applying the Penicillium sp. from the phosphate rock samples were: 100 g/1 of sucrose as a carbon source for P2O5 and U and 10 g/1 for REE, 7,15 and 10 days incubation period for P2O5 , U and REE, respectively, 0.5% solid: liquid ratio for P2O5 and 5% for U and REE. Finally, the application of phosphate rock samples grinded to -270 mesh of grain size for P2O5 and (-60 to -140) for U and REE. The studied leaching efficiency of P2O5 , U and REE gave at -270 mesh 33.66%, 24.3%, 15.9% respectively, while at -60 mesh they gave 33.76%, 26.7%, 17.8% and at -140 mesh gave 31.32%, 27.9%, 17.6%, respectively.The optimum conditions for the P2O5 leaching efficiency when applying the Pseudomonas fluorescence were: 10 g/1 of beef extract

  12. Liming effect on P availability from Maardu phosphate rock

    International Nuclear Information System (INIS)

    Thirty years ago phosphate rock from the Maardu deposit was intensively used for soil fertilization in Lithuania. However, the application of finely ground product caused an undesirable dusty operation. Afterwards, a super-phosphate production plant was built in Kedainiai and the use of phosphate rock was completely abandoned. Field experiments with fodder beets and barley were carried out to evaluate the P availability of granulated superphosphate and Maardu phosphate rock. The comparison was made at three acidity levels: a) unlimed acid soil with a high content of Al (pHkcl 4.3-4.4, hydrolytic acidity was 41-44 meq/kg soil), b) soil limed with 0.5n rate CaCO3 powder limestone based on hydrolytic acidity, and c) soil limed with 1.0n rate CaCO3. Two field experiments were carried out with fodder beets. In 1997 the yield increased significantly due to liming. However, no significant yield increases were found due to the application of phosphorus fertilizers. Differences between the effect of superphosphate and phosphate rock were also not observed. This might have been caused by a severe drought during the vegetative growth of plants. In the following year, 1998, a soil with similar acidity was chosen, however it contained even lower amounts of available phosphorus in the arable soil (about 50 mg/kg soil A-L method). In the unlimed soil the yield was low, the effect of superphosphate was better than that of phosphate rock. A good fodder beet yield of 32 to 35 t/ha was obtained and the effect of phosphate rock was better than that of superphosphate at 0.5n CaCO3 rate. When liming with at the high rate (1.0n CaCO3 rate according to hydrolytic acidity) the action of phosphate rock declined, and a better yield was obtained with superphosphate. Barley was grown after fodder beets in the 1997 experimental field and the residual effect of superphosphate and phosphate rock was investigated. Weather conditions were favorable for barley growth. Therefore a normal yield (4

  13. Structural studies of the catalytic reaction pathway of a hyperthermophilic histidinol-phosphate aminotransferase

    OpenAIRE

    Fernandez, F.J. (Francisco J.); Vega, M C; Lehmann, F; Sandmeier, E; Gehring, H; Christen, P; Wilmanns, M.

    2004-01-01

    In histidine biosynthesis, histidinol-phosphate aminotransferase catalyzes the transfer of the amino group from glutamate to imidazole acetol-phosphate producing 2-oxoglutarate and histidinol phosphate. In some organisms such as the hyperthermophile Thermotoga maritima, specific tyrosine and aromatic amino acid transaminases have not been identified to date, suggesting an additional role for histidinol-phosphate aminotransferase in other transamination reactions generating aromatic amino acid...

  14. Nitric oxide induces the alternative oxidase pathway in Arabidopsis seedlings deprived of inorganic phosphate

    OpenAIRE

    Royo, Beatriz; Moran, Jose F.; Ratcliffe, R. George; Gupta, Kapuganti J.

    2015-01-01

    Phosphate starvation compromises electron flow through the cytochrome pathway of the mitochondrial electron transport chain, and plants commonly respond to phosphate deprivation by increasing flow through the alternative oxidase (AOX). To test whether this response is linked to the increase in nitric oxide (NO) production that also increases under phosphate starvation, Arabidopsis thaliana seedlings were grown for 15 d on media containing either 0 or 1mM inorganic phosphate. The effects of th...

  15. Characterisation of Phosphate Accumulating Organisms and Techniques for Polyphosphate Detection: A Review

    OpenAIRE

    Cédric Tarayre; Huu-Thanh Nguyen; Alison Brognaux; Anissa Delepierre; Lies De Clercq; Raphaëlle Charlier; Evi Michels; Erik Meers; Frank Delvigne

    2016-01-01

    Phosphate minerals have long been used for the production of phosphorus-based chemicals used in many economic sectors. However, these resources are not renewable and the natural phosphate stocks are decreasing. In this context, the research of new phosphate sources has become necessary. Many types of wastes contain non-negligible phosphate concentrations, such as wastewater. In wastewater treatment plants, phosphorus is eliminated by physicochemical and/or biological techniques. In this latte...

  16. Physiochemical Changes and Optimization of Phosphate-Treated Shrimp (Litopenaeus vannamei ) Using Response Surface Methodology

    OpenAIRE

    Omar, Saiah Djebbour; Yang, Je-Eun; Oh, Sang-Cheol; Kim, Dae-Wook; Lee, Yang-Bong

    2016-01-01

    The objective of this study was to determine the factors responsible for the changed physiochemical properties of unpeeled shrimp treated in cold phosphate solution (2~4°C) with the intervention of 4 factors: phosphate concentration, dipping time, rotation speed, and volume of brine solution. Response surface analysis was used to characterize the effect of the phosphate treatment on shrimps by running 33 treatments for optimizing the experiment. For each treatment, phosphate amount, moisture ...

  17. Characterisation of Phosphate Accumulating Organisms and Techniques for Polyphosphate Detection: A Review

    OpenAIRE

    Tarayre, Cédric; Nguyen, Huu-Thanh; Brognaux, Alison; Delepierre, Anissa; De Clercq, Lies; Charlier, Raphaëlle; Michels, Evi; Meers, Erik; Delvigne, Frank

    2016-01-01

    Phosphate minerals have long been used for the production of phosphorus-based chemicals used in many economic sectors. However, these resources are not renewable and the natural phosphate stocks are decreasing. In this context, the research of new phosphate sources has become necessary. Many types of wastes contain non-negligible phosphate concentrations, such as wastewater. In wastewater treatment plants, phosphorus is eliminated by physicochemical and/or biological techniques...

  18. Polymer Coating for Immobilizing Soluble Ions in a Phosphate Ceramic Product

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Dileep; Wagh, Arun S.; Patel, Kartikey D.

    1999-05-05

    A polymer coating is applied to the surface of a phosphate ceramic composite to effectively immobilize soluble salt anions encapsulated within the phosphate ceramic composite. The polymer coating is made from ceramic materials, including at least one inorganic metal compound, that wet and adhere to the surface structure of the phosphate ceramic composite, thereby isolating the soluble salt anions from the environment and ensuring long-term integrity of the phosphate ceramic composite.

  19. Biosynthesis of riboflavin. Enzymatic formation of the xylene moiety from [14C]ribulose 5-phosphate.

    Science.gov (United States)

    Nielsen, P; Neuberger, G; Floss, H G; Bacher, A

    1984-02-14

    We have studied the enzymatic formation of the xylene ring of riboflavin using cell extracts from the flavinogenic yeast Candida guilliermondii. 5-Amino-6-ribitylamino-2,4(1H,3H)-pyrimidinedione or its 5'-phosphate could serve as substrates. In addition, a pentose phosphate or pentulose phosphate was required. Experiments with [14C]ribulose 5-phosphate gave evidence for the incorporation of the ribulose carbon atoms except C-4 into the xylene ring of the vitamin. PMID:6546684

  20. Pollution prevention and treatability of phosphate laden wastewater in the seafood industry

    OpenAIRE

    Krobath, Laurie J.

    1996-01-01

    Seafood processing wastewater containing high concentrations of phosphate was evaluated for its composition, applicability for reuse and recycle, and treatability for phosphate removal. Wastewater from two seafood processing industries was characterized for orthophosphate (OP), condensed phosphate (CP), total phosphate (TP), chemical oxygen demand (COD), total organic carbon (TOC), pH, and total suspended solids (TSS). Shrimp wastewater from industry one had an average pH of 6....

  1. Application of phosphating techniques to aluminium and carbon steel surfaces using nitro guanidine as oxidizing agent

    International Nuclear Information System (INIS)

    Phosphate coatings are inorganic crystalline deposits laid down uniformly on properly prepared surfaces by a chemical reaction with the treated base metal. The reaction consists in dissolving some surface metal by acid attack and then causing surface neutralization of the phosphate solution with consequent precipitation of the phosphate coating. Phosphate coatings do not provide appreciable corrosion protection in themselves. They are useful mainly as a base for paints, ensuring good adherence of paint to steel and decreasing the tendency for corrosion to under cut the paint film at scratches or other defects. In this work firstly were realized phosphate on standard carbon steel, employing technical of cold phosphate (at 40 Centigrade degrees and with a treatment time of 30 minutes) and hot phosphate (at 88 Centigrade degrees and with a treatment time of 15 minutes), where with this last were obtained the best results. Both methods used phosphate solutions of Zn/Mn and using as catalyst Nitro guanidine. Aluminium surfaces were phosphate used solutions of Cr and as catalyst Sodium bi fluoride. The phosphating on this surface were realized at temperature of 50 Centigrade degrees and with a treatment time of 10 minutes. In this work were obtained a new phosphate coatings on steel surfaces, these coatings were realized with a phosphate solution manufactured with the precipitates gathered during the hot phosphating on carbon steel. These coatings show excellent physical characteristics and of corrosion resistance. Were determined the physical testings of the coatings phosphate obtained on carbon steel and aluminium surfaces. These testing were: roughness, thickness, microhardness and adhesion. The best results were showed in carbon steel phosphate with precipitated solutions. The technical of analysis for activation with thermic neutrons was used to determine the phosphate coatings composition. Finally, corrosion testings were realized by means of two methods

  2. Uncoupling of Methanogenesis from Growth of Methanosarcina barkeri by Phosphate Limitation

    OpenAIRE

    Archer, David B.

    1985-01-01

    Production of methane by Methanosarcina barkeri from H2-CO2 was studied in fed-batch culture under phosphate-limiting conditions. A transition in the kinetics of methanogenesis from an exponentially increasing rate to a constant rate was due to depletion of phosphate from the medium. The period of exponentially increasing rate of methanogenesis was extended by increasing the initial concentration of phosphate in the medium. Addition of phosphate during the constant period changed the kinetics...

  3. Modelling and automation of the process of phosphate ion removal from waste waters

    OpenAIRE

    L. Lupa; P. Negrea; Negrea, A.; A. Iovi; L. Cocheci; G. Mosoarca

    2008-01-01

    Phosphate removal from waste waters has become an environmental necessity, since these phosphates stimulate the growth of aquatic plants and planktons and contribute to the eutrophication process in general. The physicochemical methods of phosphate ion removal are the most effective and reliable. This paper presents studies on the process of phosphate ion removal from waste waters resulting from the fertiliser industry’s use of the method of co-precipitation with iron salts and with calcium h...

  4. Comparison of phosphate materials for immobilizing cadmium in soil.

    Science.gov (United States)

    Hong, Chang Oh; Chung, Doug Young; Lee, Do Kyoung; Kim, Pil Joo

    2010-02-01

    A study was conducted to compare the effects of phosphate (P) materials in reducing cadmium extractability. Seven P materials (commercial P fertilizers--fused phosphate (FP), 'fused and superphosphate' [FSP], and rock phosphate [RP]; P chemicals--Ca[H(2)PO(4)](2).H(2)O, [NH(4)](2)HPO(4), KH(2)PO(4), and K(2)HPO(4)) were selected for the test. The selected P source was mixed with Cd-contaminated soil at the rate of 0, 200, 400, 800, and 1,600 mg P kg(-1) under controlled moisture conditions at 70% of water holding capacity, then incubated for 8 weeks. FP, Ca(H(2)PO(4))(2) H(2)O, KH(2)PO(4), and K(2)HPO(4) significantly decreased NH(4)OAc-extractable Cd (plant-available form) concentrations with increasing application rates. Compared to other phosphate materials used, K(2)HPO(4) was found to be the most effective in reducing the plant-available Cd concentration in soil, mainly due to the negative charge increase caused by soil pH and phosphate adsorption. Contrary to the general information, FSP and (NH(4))(2)HPO(4) increased Cd extractability at low levels of P application (<400 mg kg(-1)), and thereafter Cd extractability decreased significantly with increasing application rate. RP scarcely had an effect on reducing Cd extractability. Ion activity products of CdHPO(4), Cd(OH)(2), and CdCO(3) analyzed by the MINTEQ program were significantly increased by K(2)HPO(4) addition, but the effect of Cd-P compound formation on reducing Cd extractability was negligible. Conclusively, the P-induced alleviation of Cd extractability can be attributed primarily to Cd immobilization due to the increase in soil pH and negative charge rather than Cd-P precipitation, and therefore, alkaline P materials such as K(2)HPO(4) are effective for immobilizing soil Cd. PMID:19633979

  5. Phosphate removal from domestic wastewater using thermally modified steel slag.

    Science.gov (United States)

    Yu, Jian; Liang, Wenyan; Wang, Li; Li, Feizhen; Zou, Yuanlong; Wang, Haidong

    2015-05-01

    This study was performed to investigate the removal of phosphate from domestic wastewater using a modified steel slag as the adsorbent. The adsorption effects of alkalinity, salt, water, and thermal modification were investigated. The results showed that thermal activation at 800°C for 1 hr was the optimum operation to improve the adsorption capacity. The adsorption process of the thermally modified slag was well described by the Elovich kinetic model and the Langmuir isotherm model. The maximum adsorption capacity calculated from the Langmuir model reached 13.62 mg/g. Scanning electron microscopy indicated that the surface of the modified slag was cracked and that the texture became loose after heating. The surface area and pore volume did not change after thermal modification. In the treatment of domestic wastewater, the modified slag bed (35.5 kg) removed phosphate effectively and operated for 158 days until the effluent P rose above the limit concentration of 0.5 mg/L. The phosphate fractionation method, which is often applied in soil research, was used to analyze the phosphate adsorption behavior in the slag bed. The analysis revealed that the total contents of various Ca-P forms accounted for 81.4%-91.1%, i.e., Ca10-P 50.6%-65.1%, Ca8-P 17.8%-25.0%, and Ca2-P 4.66%-9.20%. The forms of Al-P, Fe-P, and O-P accounted for only 8.9%-18.6%. The formation of Ca10-P precipitates was considered to be the main mechanism of phosphate removal in the thermally modified slag bed. PMID:25968262

  6. Radiological and chemical assessment of phosphate rocks in some countries

    Energy Technology Data Exchange (ETDEWEB)

    Cevik, U., E-mail: ugurc@ktu.edu.tr [Karadeniz Technical University, Department of Physics, Trabzon (Turkey); Baltas, H. [Rize University, Department of Physics, Rize (Turkey); Tabak, A. [Rize University, Department of Chemistry, Rize (Turkey); Damla, N. [Batman University, Department of Physics, Batman (Turkey)

    2010-10-15

    In this study, the radiological, structural and chemical characterizations of Mardin-Mazidagi phosphate rock, which is an important phosphate fertilizer source in Turkey were investigated and compared to those of several different phosphate rocks of Tunisia, Egypt, Morocco, Algeria and Syria using gamma spectrometry, X-ray diffraction (XRD) and X-ray fluorescence (XRF) measurement techniques. Elemental analysis results of phosphate samples showed that they were mainly composed of CaO, P{sub 2}O{sub 5}, SiO{sub 2}, Al{sub 2}O{sub 3}, SO{sub 3} and Fe{sub 2}O{sub 3}. Elemental concentrations of U and Th were calculated using {sup 226}Ra and {sup 232}Th activity concentrations, respectively. As a result of XRD analysis, the main peaks of the samples were found to be Fluorapatite (Ca{sub 5}(PO{sub 4}){sub 3}F). The radioactivity concentration levels for {sup 226}Ra, {sup 232}Th and {sup 40}K in all phosphate samples ranged from 250 to 1029 Bq kg{sup -1} with a mean of 535 Bq kg{sup -1}, from 5 to 50 Bq kg{sup -1} with a mean of 20 Bq kg{sup -1} and from 117 to 186 Bq kg{sup -1} with a mean of 148 Bq kg{sup -1}, respectively. The computed values of annual effective doses ranged from 0.17 to 0.59 mSv, with a mean value of 0.33 mSv, which is lower than the recommended limit of 1 mSv y{sup -1} by the International Commission on Radiological Protection.

  7. Spectroscopic properties of highly Nd-doped lead phosphate glass

    Energy Technology Data Exchange (ETDEWEB)

    Novais, A.L.F. [Instituto de Física, Universidade Federal de Alagoas, Grupo de Fotônica e Fluidos Complexos, 57072-970 Maceió, AL (Brazil); Dantas, N.O. [Laboratório de Novos Materiais Isolantes e Semicondutores (LNMIS), Instituto de Física, Universidade Federal de Uberlândia, 38400-902 Uberlândia, MG (Brazil); Guedes, I. [Departamento de Física, Universidade Federal do Ceará, Campus do PICI, Caixa Postal 6030, 60455-760 Fortaleza, CE (Brazil); Vermelho, M.V.D., E-mail: vermelho@fis.ufal.br [Instituto de Física, Universidade Federal de Alagoas, Grupo de Fotônica e Fluidos Complexos, 57072-970 Maceió, AL (Brazil)

    2015-11-05

    The spectroscopic characteristics of highly Nd{sup 3+}-doped lead phosphate glasses (xNd:Pb{sub 3}(PO{sub 4}){sub 2}) have been investigated. The X-ray spectra show that the matrices are glassy up to 25 wt% of Nd{sup 3+} doping. From the Judd–Ofelt analysis we observe that while the Ω{sub (2)} parameter remains constant indicating that the 4f{sup N} and 4f{sup N−1}5 d{sup 1} configurations are not affected by the Nd{sup 3+} doping, the behavior of both Ω{sub (4)} and Ω{sub (6)} changes for 15 wt% of Nd{sup 3+} doping. The reduction of the Ω{sub (6)} parameter is related to the increase of the covalence bonding between the ligands and the Nd{sup 3+} ions. At this particular concentration, the radiative lifetime has a four-fold enhancement. Such behaviors are likely to be related to a modification in the glass structure for high Nd{sup 3+} concentrations. - Graphical abstract: Highly doped lead-phosphate glass matrix, with nominal concentration of up to 25 wt%, maintain the spectroscopic properties without deterioration. The analysis concerning the point of view of Nd{sup 3+} ions showed that high concentrations only affects the rare earth electronic charge density distribution. - Highlights: • Spectroscopic characterization of Nd{sub 2}O{sub 3} highly doped lead phosphate glasses. • Phosphate glass doped with Nd{sup 3+} for applications in photonic devices. • Judd–Ofelt analysis in phosphate glasses doped with Neodymium.

  8. 40 CFR 721.6000 - Tris (2,3-dibromopropyl) phosphate.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Tris (2,3-dibromopropyl) phosphate... Substances § 721.6000 Tris (2,3-dibromopropyl) phosphate. (a) Chemical substance and significant new use subject to reporting. (1) The chemical substance tris (2,3-dibromopropyl) phosphate (CAS Number...

  9. Use of a La(III)-modified bentonite for effective phosphate removal from aqueous media

    International Nuclear Information System (INIS)

    Highlights: • A phosphate adsorbent was prepared from unpurified natural bentonite. • Physisorption was found to the main phosphate interaction mechanism. • The retention has reached 95% of the phosphate present in solution at room temperature. • The rate sorption was about 4 times faster than commercial phosphate adsorbents. - Abstract: A bentonite from the Northeast Brazilian region was modified with lanthanum (NT-25La) using an ion exchange process. Lanthanum incorporation in the natural clay, as well as the properties of the clay materials, were confirmed by X-ray diffraction, X-ray fluorescence, specific surface area and scanning electron microscopy (SEM/EDX). Phosphate adsorption equilibrium and kinetic tests were performed at different temperatures. The adsorption data have shown that NT-25La reaches equilibrium between modified clay and phosphate solution within 60 min of contact. The phosphate retention at room temperature reached 95%, when initial phosphate concentration in solution was 5 mg L−1. A kinetic-order variable model provided satisfactory fitting of the kinetic data. Adsorption of phosphate was best described by a Langmuir isotherm, with maximum phosphate sorption capacity of 14.0 mg g−1. Two distinct adsorption mechanisms were observed that may influence the adsorption processes. The investigation pointed out that the phosphate adsorption occurs via physisorption processes and that the use of NT-25La provides a maximum phosphate sorption capacity higher than many commercial adsorbents

  10. Natural radionuclides in phosphatic fertilizer and their behaviour of absoption and accumulation in soils and crops

    International Nuclear Information System (INIS)

    The systematic data on the radioactivity of U, Th, Ra and 40K in phosphate rocks, phosphatic fertilizers and soil are given. The radioactive composition and radioactivity in phosphatic fertilizers vary with different kinds of phosphatic fertilizers. The radioactive compositions in the phosphatic fertilizers made from phosphate rock are the same as that in the original phosphate rock, but the radioactivity is only 50∼60% of the original. The natural uranium in the compound fertilizer made from phosphoric acid is several times higher than that in the phosphate rock, and the other radionuclides were separated during the process of forming phosphoric acid. In soil, the radioactivity varies with the soil types. The U content is slightly higher in the south region with red earth and the 40K is higher in the north region with black earth, but all are in normal level. Usually, the radioactivity of phosphate rock and phosphatic fertilizer is between the natural background of soil and the limitation of radioactive protection, but the radioactivity of 226Ra in some phosphate rocks and phosphatic fertilizers in Guizhou and Hunan is higher than the permitted limitation set by the government

  11. Organisation and sequence determination of glutamine-dependent carbamoyl phosphate synthetase II in Toxoplasma gondii.

    Science.gov (United States)

    Fox, Barbara A; Bzik, David J

    2003-01-01

    Carbamoyl phosphate synthetase II encodes the first enzymic step of de novo pyrimidine biosynthesis. Carbamoyl phosphate synthetase II is essential for Toxoplasma gondii replication and virulence. In this study, we characterised the primary structure of a 28kb gene encoding Toxoplasma gondii carbamoyl phosphate synthetase II. The carbamoyl phosphate synthetase II gene was interrupted by 36 introns. The predicted protein encoded by the 37 carbamoyl phosphate synthetase II exons was a 1,687 amino acid polypeptide with an N-terminal glutamine amidotransferase domain fused with C-terminal carbamoyl phosphate synthetase domains. This bifunctional organisation of carbamoyl phosphate synthetase II is unique, so far, to protozoan parasites from the phylum Apicomplexa (Plasmodium, Babesia, Toxoplasma) or zoomastigina (Trypanosoma, Leishmania). Apicomplexan parasites possessed the largest carbamoyl phosphate synthetase II enzymes due to insertions in the glutamine amidotransferase and carbamoyl phosphate synthetase domains that were not present in the corresponding gene segments from bacteria, plants, fungi and mammals. The C-terminal allosteric regulatory domain, the carbamoyl phosphate synthetase linker domain and the oligomerisation domain were also distinct from the corresponding domains in other species. The novel C-terminal regulatory domain may explain the lack of activation of Toxoplasma gondii carbamoyl phosphate synthetase II by the allosteric effector 5-phosphoribosyl 1-pyrophosphate. Toxoplasma gondii growth in vitro was markedly inhibited by the glutamine antagonist acivicin, an inhibitor of glutamine amidotransferase activity typically associated with carbamoyl phosphate synthetase II, guanosine monophosphate synthetase, or CTP synthetase. PMID:12547350

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

    NARCIS (Netherlands)

    Tervahauta, T.H.; Weijden, van der R.D.; Flemming, R.L.; Hernández, L.; Zeeman, G.; Buisman, C.J.N.

    2014-01-01

    Recovery of phosphorus from wastewater as calcium phosphate could diminish the need for mining of scarce phosphate rock resources. This study introduces a novel approach to phosphorus recovery by precipitation of calcium phosphate granules in anaerobic treatment of black water. The granules formed i

  13. Use of a La(III)-modified bentonite for effective phosphate removal from aqueous media

    Energy Technology Data Exchange (ETDEWEB)

    Kuroki, Vivian; Bosco, Giulianna E. [Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Rua Santa Adélia, 166, Santo André CEP 09210-170, SP (Brazil); Fadini, Pedro S.; Mozeto, Antonio A. [Laboratório de Biogeoquímica Ambiental, Núcleo de Estudos, Diagnósticos e Intervenções Ambientais, Departamento de Química, Universidade Federal de São Carlos, Cx. Postal 676, São Carlos CEP 13565-905, SP (Brazil); Cestari, Antonio R. [Department of Chemistry/CCET, Universidade Federal de Sergipe, São Cristóvão CEP 49100-000, SE (Brazil); Carvalho, Wagner A., E-mail: wagner.carvalho@ufabc.edu.br [Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Rua Santa Adélia, 166, Santo André CEP 09210-170, SP (Brazil)

    2014-06-01

    Highlights: • A phosphate adsorbent was prepared from unpurified natural bentonite. • Physisorption was found to the main phosphate interaction mechanism. • The retention has reached 95% of the phosphate present in solution at room temperature. • The rate sorption was about 4 times faster than commercial phosphate adsorbents. - Abstract: A bentonite from the Northeast Brazilian region was modified with lanthanum (NT-25La) using an ion exchange process. Lanthanum incorporation in the natural clay, as well as the properties of the clay materials, were confirmed by X-ray diffraction, X-ray fluorescence, specific surface area and scanning electron microscopy (SEM/EDX). Phosphate adsorption equilibrium and kinetic tests were performed at different temperatures. The adsorption data have shown that NT-25La reaches equilibrium between modified clay and phosphate solution within 60 min of contact. The phosphate retention at room temperature reached 95%, when initial phosphate concentration in solution was 5 mg L{sup −1}. A kinetic-order variable model provided satisfactory fitting of the kinetic data. Adsorption of phosphate was best described by a Langmuir isotherm, with maximum phosphate sorption capacity of 14.0 mg g{sup −1}. Two distinct adsorption mechanisms were observed that may influence the adsorption processes. The investigation pointed out that the phosphate adsorption occurs via physisorption processes and that the use of NT-25La provides a maximum phosphate sorption capacity higher than many commercial adsorbents.

  14. 21 CFR 524.1883 - Prednisolone sodium phosphate-neomycin sulfate ophthalmic ointment.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Prednisolone sodium phosphate-neomycin sulfate... DOSAGE FORM NEW ANIMAL DRUGS § 524.1883 Prednisolone sodium phosphate-neomycin sulfate ophthalmic ointment. (a) Specifications. Prednisolone sodium phosphate-neomycin sulfate ophthalmic ointment...

  15. Allergic contact dermatitis from sodium dihydroxycetyl phosphate, a new cosmetic allergen?

    DEFF Research Database (Denmark)

    Lomholt, H; Rastogi, S C; Andersen, Klaus Ejner

    2001-01-01

    Sodium dihydroxycetyl phosphate (trade name Dragophos S 2/918501) was identified as a contact allergen in a herbal moisturizing cream causing severe acute contact dermatitis on the hands and face of a 41-year-old woman. Sodium dihydroxycetyl phosphate is a complex mixture of phosphate esters of d...

  16. 40 CFR 721.6180 - Polyalkylene glycol polyamide ester phosphate (generic).

    Science.gov (United States)

    2010-07-01

    ... phosphate (generic). 721.6180 Section 721.6180 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.6180 Polyalkylene glycol polyamide ester phosphate (generic). (a... generically as polyalkylene glycol polyamide ester phosphate (PMN P-98-0903) is subject to reporting...

  17. 76 FR 38389 - Caraleigh Phosphate and Fertlizer Works Superfund Site; Raleigh, Wake County, NC; Notice of...

    Science.gov (United States)

    2011-06-30

    ... AGENCY Caraleigh Phosphate and Fertlizer Works Superfund Site; Raleigh, Wake County, NC; Notice of... response costs concerning the Caraleigh Phosphate and Fertilizer Works Superfund Site located in Raleigh...-0534 or Site name Caraleigh Phosphate and Fertilizer Works Superfund Site by one of the...

  18. Structural Basis for Substrate Specificity in Phosphate Binding (beta/alpha)8-Barrels: D-Allulose 6-Phosphate 3-Epimerase from Escherichia coli K-12

    Energy Technology Data Exchange (ETDEWEB)

    Chan,K.; Fedorov, A.; Almo, S.; Gerlt, J.

    2008-01-01

    Enzymes that share the ({beta}/{alpha})8-barrel fold catalyze a diverse range of reactions. Many utilize phosphorylated substrates and share a conserved C-terminal ({beta}/a)2-quarter barrel subdomain that provides a binding motif for the dianionic phosphate group. We recently reported functional and structural studies of d-ribulose 5-phosphate 3-epimerase (RPE) from Streptococcus pyogenes that catalyzes the equilibration of the pentulose 5-phosphates d-ribulose 5-phosphate and d-xylulose 5-phosphate in the pentose phosphate pathway [J. Akana, A. A. Fedorov, E. Fedorov, W. R. P. Novack, P. C. Babbitt, S. C. Almo, and J. A. Gerlt (2006) Biochemistry 45, 2493-2503]. We now report functional and structural studies of d-allulose 6-phosphate 3-epimerase (ALSE) from Escherichia coli K-12 that catalyzes the equilibration of the hexulose 6-phosphates d-allulose 6-phosphate and d-fructose 6-phosphate in a catabolic pathway for d-allose. ALSE and RPE prefer their physiological substrates but are promiscuous for each other's substrate. The active sites (RPE complexed with d-xylitol 5-phosphate and ALSE complexed with d-glucitol 6-phosphate) are superimposable (as expected from their 39% sequence identity), with the exception of the phosphate binding motif. The loop following the eighth {beta}-strand in ALSE is one residue longer than the homologous loop in RPE, so the binding site for the hexulose 6-phosphate substrate/product in ALSE is elongated relative to that for the pentulose 5-phosphate substrate/product in RPE. We constructed three single-residue deletion mutants of the loop in ALSE, ?T196, ?S197 and ?G198, to investigate the structural bases for the differing substrate specificities; for each, the promiscuity is altered so that d-ribulose 5-phosphate is the preferred substrate. The changes in kcat/Km are dominated by changes in kcat, suggesting that substrate discrimination results from differential transition state stabilization. In both ALSE and RPE, the

  19. From energy-rich phosphate compounds to warfare agents: A review on the chemistry of organic phosphate compounds

    Directory of Open Access Journals (Sweden)

    Luciano Albino Giusti

    2008-12-01

    Full Text Available The chemistry of the phosphorus-oxygen bond is widely used in biological systems in many processes, such as energy transduction and the storage, transmission and expression of genetic information, which are essential to living beings in relation to a wide variety of functions. Compounds containing this bond have been designed for many purposes, ranging from agricultural defense systems, in order to increase food production, to nerve agents, for complaining use in warfare. In this review, features related to the chemistry of organic phosphate compounds are discussed, with particular emphasis on the role of phosphate compounds in biochemical events and in nerve agents. To this aim, the energy-rich phosphate compounds are focused, particularly the mode of their use as energy currency in cells. Historical and recent studies carried out by research groups have tried to elucidate the mechanism of action of enzymes responsible for energy transduction through the use of biochemical studies, enzyme models, and artificial enzymes. Finally, recent studies on the detoxification of nerve agents based on phosphorous esters are presented, and on the utilization of chromogenic and fluorogenic chemosensors for the detection of these phosphate species.

  20. Mechanism of calcium phosphates precipitation in liquid crystals; Mecanisme de precipitation de phosphates de calcium dans des cristaux liquides

    Energy Technology Data Exchange (ETDEWEB)

    Prelot, B.; Zemb, T

    2004-04-01

    The possibility of using as a precursor an easily wet meso-porous powder would be a breakthrough in the preparation of nuclear waste storage ceramics. A concentrated solution containing ions to be stored would wet a dry powder and then, subjected to mild compression, lead to a micro-crystalline matrix of calcium phosphate at acceptable temperatures. Since no porous calcium phosphate different from calcined bone (patented) is described as porous precursor, we have compared the different synthesis routes towards meso-porous ceramics. First, we considered homogeneous precipitation of slats in water: using initially off-stoichiometry in reaction, micron-sized hydroxyapatite particles are produced with a specific surface up to 100 m{sup 2}/g. Then, we consider the classical route of precipitation of an hybrid material in the miscibility gap of a phase diagram, when an hexagonal liquid crystal is used a matrix for precipitation. The surfactant family consists in single chain surfactants containing phosphates as head-group to poison the growing surface of calcium phosphate nano-domains. Since the reaction is still too brutal, we considered using a cat-anionic precursor material of controllable surface charge. For certain concentrations and molar ratios, a new structure not yet described in surfactant precipitation literature is observed: since the periodicity is lower than twice the chain length, a disordered constant curvature monolayer (instead of the classical cylinder of twice chain length diameter) of surfactant is implied. Finally, we have investigated synthesis routes implying slow dissolution of pre-formed calcium phosphate in an already existing hexagonal matrix. For all these routes of synthesis, micro-structural determinations using SAXS, WARS and BET are performed, with a special attention to comparison of the precipitation material, the matrix obtained with all elements present, and also the material obtained after calcinations. (authors)