WorldWideScience

Sample records for toxic phosphorus esters

  1. Yellow phosphorus process to convert toxic chemicals to non-toxic products

    Science.gov (United States)

    Chang, S.G.

    1994-07-26

    The present invention relates to a process for generating reactive species for destroying toxic chemicals. This process first contacts air or oxygen with aqueous emulsions of molten yellow phosphorus. This contact results in rapid production of abundant reactive species such as O, O[sub 3], PO, PO[sub 2], etc. A gaseous or liquid aqueous solution organic or inorganic chemicals is next contacted by these reactive species to reduce the concentration of toxic chemical and result in a non-toxic product. The final oxidation product of yellow phosphorus is phosphoric acid of a quality which can be recovered for commercial use. A process is developed such that the byproduct, phosphoric acid, is obtained without contamination of toxic species in liquids treated. A gas stream containing ozone without contamination of phosphorus containing species is also obtained in a simple and cost-effective manner. This process is demonstrated to be effective for destroying many types of toxic organic, or inorganic, compounds, including polychlorinated biphenyls (PCB), aromatic chlorides, amines, alcohols, acids, nitro aromatics, aliphatic chlorides, polynuclear aromatic compounds (PAH), dyes, pesticides, sulfides, hydroxyamines, ureas, dithionates and the like. 20 figs.

  2. REPRODUCTIVE TOXICITY OF PHTHALATE ESTERS

    Science.gov (United States)

    Phthalate esters display several modes of toxicity in mammalian species. In the rat, in utero exposure at relatively low dosage levels disrupts development of the reproductive system of the male rat by altering fetal testis hormone production. This presentation is a review of t...

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

    Energy Technology Data Exchange (ETDEWEB)

    Neil, L.L.; McCullough, C.D.; Lund, M.A.; Evans, L.H.; Tsvetnenko, Y. [Edith Cowan University, Joondalup, WA (Australia)

    2009-11-15

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

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

    Science.gov (United States)

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

    2009-11-01

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

  5. Phthalate Esters and Reproductive Toxicity** Presentation requested by State of Mass Use Reductions Committee-TURI

    Science.gov (United States)

    Phthalate esters and reproductive toxicity the presentation described the uses of phthalates, the toxicity to mammals with a focus on reproductive toxicity and the potency of these chemicals to disrupt mammalian reproductive development in utero

  6. Selective solvation extraction of gold from alkaline cyanide solution by alkyl phosphorus esters

    Energy Technology Data Exchange (ETDEWEB)

    Miller, J.D.; Wan, R.Y.; Mooiman, M.B.; Sibrell, P.L.

    1987-01-01

    Research efforts have shown that solvation extraction of gold from alkaline cyanide solution is possible by alkyl phosphorus esters. Both tributyl phosphate (TBP) and dibutyl butyl phosphonate (DBBP) appear to be effective extractants for gold and exhibit high loading capacities exceeding 30 gpl. Selective solvation extraction of gold from alkaline cyanide solution can be achieved with selectivity factors relative to other cyanoanions as high as 1000 under certain circumstances. Variables influencing the selectivity such as ionic strength, temperature, and extractant structure, are discussed in terms of the extraction chemistry, which seems to involve the solvation of a M dot, dot, dot Au(CN)2 ion pair.

  7. Amendment in phosphorus levels moderate the chromium toxicity in Raphanus sativus L. as assayed by antioxidant enzymes activities.

    Science.gov (United States)

    Sayantan, D; Shardendu

    2013-09-01

    Chromium (Z=24), a d-block element, is a potent carcinogen, whereas phosphorus is an essential and limiting nutrient for the plant growth and development. This study undertakes the role of phosphorus in moderating the chromium toxicity in Raphanus sativus L., as both of them compete with each other during the uptake process. Two-factor complete randomized experiment (5 chromium × 5 phosphorus concentrations) was conducted for twenty eight days in green house. The individuals of R. sativus were grown in pots supplied with all essential nutrients. The toxic effects of chromium and the moderation of toxicity due to phosphorus amendment were determined as accumulation of chromium, nitrogen, phosphorus in root tissues and their effects were also examined in the changes in biomass, chlorophyll and antioxidant enzyme levels. Cr and N accumulation were almost doubled at the highest concentration of Cr supply, without any P amendment, whereas at the highest P concentration (125 mM), the accumulation was reduced to almost half. A significant reduction in toxic effects of Cr was determined as there was three-fold increase in total chlorophyll and biomass at the highest P amendment. Antioxidant enzymes like superoxide dismutase, catalase, peroxidase and lipid peroxidation were analyzed at various levels of Cr each amended with five levels of P. It was observed that at highest level of P amendment, the reduction percentage in toxicity was 33, 44, 39 and 44, correspondingly. Conclusively, the phosphorus amendment moderates the toxicity caused by the supplied chromium in R. sativus. This finding can be utilized to develop a novel technology for the amelioration of chromium stressed fields. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Occular and dermal toxicity of Jatropha curcas phorbol esters.

    Science.gov (United States)

    Devappa, Rakshit K; Roach, Joy S; Makkar, Harinder P S; Becker, Klaus

    2013-08-01

    Jatropha curcas seeds are a promising feedstock for biodiesel production. However, Jatropha seed oil and other plant parts are toxic due to the presence of phorbol esters (PEs). The ever-increasing cultivation of toxic genotype of J. curcas runs the risk of increased human exposure to Jatropha products. In the present study, effects of J. curcas oil (from both toxic and nontoxic genotypes), purified PEs-rich extract and purified PEs (factors C1, C2, C(3mixture), (C4+C5)) on reconstituted human epithelium (RHE) and human corneal epithelium (HCE) were evaluated in vitro. The PEs were purified from toxic Jatropha oil. In both RHE and HCE, the topical application of PEs containing samples produced severe cellular alterations such as marked oedema, presence of less viable cell layers, necrosis and/or partial tissue disintegration in epithelium and increased inflammatory response (interleukin-1α and prostaglandin E2). When compared to toxic oil, histological alterations and inflammatory response were less evident (PJatropha PEs are toxic towards RHE and HCE models, which represents dermal and occular toxicity respectively. Data obtained from this study would aid in the development of safety procedures for Jatropha biodiesel industries. It is advised to use protective gloves and glasses when handling PEs containing Jatropha products. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Preparation of five 3-MCPD fatty acid esters, and the effects of their chemical structures on acute oral toxicity in Swiss mice.

    Science.gov (United States)

    Liu, Man; Liu, Jie; Wu, Yizhen; Gao, Boyan; Wu, Pingping; Shi, Haiming; Sun, Xiangjun; Huang, Haiqiu; Wang, Thomas Ty; Yu, Liangli Lucy

    2017-02-01

    3-monochloro-1, 2-propanediol fatty acid esters (3-MCPDEs) comprise a group of food toxicants formed during food processing. 3-MCPDEs have received increasing attention concerning their potential negative effects on human health. However, reports on the toxicity of 3-MCPD esters are still limited. To determine the effects of fatty acid substitutions on the toxicity of their esters, 1-stearic, 1-oleic, 1-linoleic, 1-linoleic-2-palmitic and 1-palmitic-2-linoleic acid esters of 3-MCPD were synthesized and evaluated with respect to their acute oral toxicities in Swiss mice. 3-MCPDEs were obtained through the reaction of 3-MCPD and fatty acid chlorides, and their purities and structures were characterized by ultraperformance liquid chromatography-quadrupole-time of flight-mass spectrometry (UPLC-Q-TOF-MS), infrared, 1 H and 13 C spectroscopic analyses. Medial lethal doses of 1-stearic, 1-oleic, 1-linoleic, 1-linoleic-2-palmitic and 1-palmitic-2-linoleic acid esters were 2973.8, 2081.4, 2016.3, 5000 and > 5000 mg kg -1 body weight. For the first time, 3-MCPDEs were observed for their toxic effects in the thymus and lung. In addition, major histopathological changes, as well as blood urea nitrogen and creatinine, were examined for mice fed the five 3-MCPDEs. The results from the present study suggest that the degree of unsaturation, chain length, number of substitution and relative substitution locations of fatty acids might alter the toxicity of 3-MCPDEs. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  10. Effect of water treatment residuals on soil phosphorus, copper and aluminium availability and toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Lombi, E., E-mail: enzo.lombi@unisa.edu.a [CSIRO Land and Water, Centre for Environmental Contaminant Research, PMB 2, Glen Osmond, SA 5064 (Australia); Centre for Environmental Risk Assessment and Remediation, University of South Australia, Building X, Mawson Lakes Campus, Mawson Lakes, SA 5095 (Australia); CRC CARE, PO Box 486, Salisbury, SA 5106 (Australia); Stevens, D.P. [CSIRO Land and Water, Centre for Environmental Contaminant Research, PMB 2, Glen Osmond, SA 5064 (Australia); Arris Pty Ltd, PO Box 5143, Burnley, Victoria 3121 (Australia); McLaughlin, M.J. [CSIRO Land and Water, Centre for Environmental Contaminant Research, PMB 2, Glen Osmond, SA 5064 (Australia); Soil and Land Systems, University of Adelaide, PMB 1, Glen Osmond, SA 5064 (Australia)

    2010-06-15

    Water treatment residuals (WTRs) are produced by the treatment of potable water with coagulating agents. Beneficial recycling in agriculture is hampered by the fact that WTRs contain potentially toxic contaminants (e.g. copper and aluminium) and they bind phosphorus strongly. These issues were investigated using a plant bioassay (Lactuca sativa), chemical extractions and an isotopic dilution technique. Two WTRs were applied to an acidic and a neutral pH soil at six rates. Reductions in plant growth in amended soils were due to WTR-induced P deficiency, rather than Al or Cu toxicity. The release of potentially toxic Al from WTRs was found to be mitigated by their alkaline nature and pH buffering capacity. However, acidification of WTRs was shown to release more soluble Al than soil naturally high in Al. Copper availability was relatively low in all treatments. However, the lability of WTR-Cu increased when the WTR was applied to the soil. - The effect of water treatment residue application to soil was investigated in relation to phosphorus availability, and copper and aluminium phytotoxicity.

  11. Effect of water treatment residuals on soil phosphorus, copper and aluminium availability and toxicity

    International Nuclear Information System (INIS)

    Lombi, E.; Stevens, D.P.; McLaughlin, M.J.

    2010-01-01

    Water treatment residuals (WTRs) are produced by the treatment of potable water with coagulating agents. Beneficial recycling in agriculture is hampered by the fact that WTRs contain potentially toxic contaminants (e.g. copper and aluminium) and they bind phosphorus strongly. These issues were investigated using a plant bioassay (Lactuca sativa), chemical extractions and an isotopic dilution technique. Two WTRs were applied to an acidic and a neutral pH soil at six rates. Reductions in plant growth in amended soils were due to WTR-induced P deficiency, rather than Al or Cu toxicity. The release of potentially toxic Al from WTRs was found to be mitigated by their alkaline nature and pH buffering capacity. However, acidification of WTRs was shown to release more soluble Al than soil naturally high in Al. Copper availability was relatively low in all treatments. However, the lability of WTR-Cu increased when the WTR was applied to the soil. - The effect of water treatment residue application to soil was investigated in relation to phosphorus availability, and copper and aluminium phytotoxicity.

  12. Toxicity of phosphor esters: Willy Lange (1900-1976) and Gerda von Krueger (1907-after 1970).

    Science.gov (United States)

    Petroianu, G A

    2010-10-01

    In 1851 Williamson serendipitously discovered a new and efficient way to produce ethers using ethyl iodide and potassium salts. Based on this new synthetic approach, the Frenchman Philippe de Clermont and the Muscovite Wladimir Moschnin, both élèves of Adolphe Wurtz in his Paris School of Chemistry, achieved the synthesis of the first ester of pyrophosphoric acid (TEPP). de Clermont "tasted" the new compound and although TEPP is a potent cholinesterase inhibitor he failed to recognize its toxicity. Almost a century later, in 1932, Willy Lange (1900-1976) and his graduate student Gerda v. Krueger (1907-after 1970) described the toxicity of organophosphonates. While the classic paper of the two "Uber Ester der Monofluorphosphorsäure." is cited by almost everybody working in the field, little is known about Lange and almost nothing about v. Krueger. This brief communication attempts to shed some light on the life of both.

  13. QSAR for cholinesterase inhibition by organophosphorus esters and CNDO/2 calculations for organophosphorus ester hydrolysis

    Science.gov (United States)

    Johnson, H.; Kenley, R. A.; Rynard, C.; Golub, M. A.

    1985-01-01

    Quantitative structure-activity relationships were derived for acetyl- and butyrylcholinesterase inhibition by various organophosphorus esters. Bimolecular inhibition rate constants correlate well with hydrophobic substituent constants, and with the presence or absence of catonic groups on the inhibitor, but not with steric substituent constants. CNDO/2 calculations were performed on a separate set of organophosphorus esters, RR'P(O)X, where R and R' are alkyl and/or alkoxy groups and X is fluorine, chlorine or a phenoxy group. For each subset with the same X, the CNDO-derived net atomic charge at the central phosphorus atom in the ester correlates well with the alkaline hydrolysis rate constant. For the whole set of esters with different X, two equations were derived that relate either charge and leaving group steric bulk, or orbital energy and bond order to the hydrogen hydrolysis rate constant.

  14. Acute toxicity and sublethal effects of white phosphorus in mute swans, Cygnus olor

    Science.gov (United States)

    Sparling, D.W.; Day, D.; Klein, P.

    1999-01-01

    Among the waterfowl affected by white phosphorus (P4) at a military base in Alaska are tundra (Cygnus columbianus) and trumpeter (C. buccinator) swans. To estimate the toxicity of P4 to swans and compare the toxic effects to those of mallards (Anas platyrhynchos), we dosed 30 juvenile mute swans (C. olor) with 0 to 5.28 mg P4 /kg body weight. The estimated LD50 was 3.65 mg/kg (95% CI: 1.40 to 4.68 mg/kg). However, many of the swans still had P4 in their gizzards after dying, as determined by 'smoking gizzards', and a lower LD50 might be calculated if all of the P4 had passed into the small intestines. We attribute the retention of P4 in swans to the presence of coarse sandlike particles of grit which were of similar size as the P4 pellets. Most swans took 1 to 4.5 days to die in contrast to the few hours normally required in mallards and death appeared to related more to liver dysfunction than to hemolysis. White phosphorus affected several plasma constituents, most notably elevated aspartate amiontransferase, blood urea nitrogen, lactate dehydrogenase, and alanine aminotransferase.

  15. Environmentally friendly properties of vegetable oil methyl esters

    Directory of Open Access Journals (Sweden)

    Gateau Paul

    2005-07-01

    Full Text Available Measurements were carried out on Vegetable Oil Methyl Esters (VOME or FAME answering the most recent specifications. The products tested are RME (Rapeseed oil Methyl Ester, ERME (Erucic Rapeseed oil Methyl Esters, SME (Sunflower oil Methyl Esters, and HOSME (High Oleic Sunflower oil Methyl Esters. They contain more than 99.5% of fatty acid mono esters. The compositions are given. VOME are not volatile and they are not easily flammable. They are not soluble in water and they are biodegradable. According to the methods implemented for the determination of the German classification of substances hazardous to waters WGK, they are not toxic on mammals and unlike diesel fuel they are not toxic on fish, daphnia, algae and bacteria. The RME is not either toxic for shrimps. According to tests on rabbits, RME and SME are not irritating for the skin and the eyes. VOME display particularly attractive environmental properties.

  16. Total phosphorus recovery in flowback fluids after gelled hydrocarbon fracturing fluid treatments

    Energy Technology Data Exchange (ETDEWEB)

    Fyten, G.; Houle, P.; Taylor, R.S. [Halliburton Energy Services, Calgary, AB (Canada); Stemler, P.S. [Petro-Canada Oil and Gas Inc., Calgary, AB (Canada); Lemieux, A. [Omnicon Consultants Inc., Calgary, AB (Canada)

    2006-07-01

    Carbon dioxide miscible hydrocarbon fracturing fluids are used in unconventional gas reservoirs such as tight gas, shale gas, and coalbed methane. These fracturing fluids address phase trapping concerns by using oil-based fracturing fluid technology for use in reservoirs that are water sensitive. This paper addressed the problem of refinery tower fouling caused by volatile phosphorous components found in phosphate ester oil gellants. In order to address costly unplanned refinery shutdowns, a maximum 0.5 ppm volatile phosphorus in crude specification has been proposed. However, this specification is based on average concentrations of phosphorus added to the oil to gel it. The specification also falsely assumes that the oil is phosphorus free to begin with. The authors noted that refinery tower fouling is actually the result of total phosphorus throughput rather than peak concentrations at any one point. This paper focused on the total phosphorus recovery in addition to peak concentrations. It also examined what percentage of the total recovered phosphorus is in fact volatile, since this is the material that plugs the trays. The total per cent recovery of phosphorus originally added as phosphorus based gellant was examined along with the total percent recovery of volatile phosphorus as a function of total phosphorus. The phosphorus concentrations in both new and reused fracturing fluids before addition of gellants was also examined along with the potential explanations for phosphorus concentrations higher than those originally added. It was shown that the first 50 per cent of a hydraulic fracturing fluid flowback can result in recovery of greater than or less than the amount of phosphorus added to that portion of the fracturing fluid. The initial high concentrations of total and volatile phosphorus are greater than the phosphorus concentrations inherent in the system. Therefore, as flowback continues, there would be a rapid decline in the concentration of phosphorus

  17. Involvement of Antioxidative Defense System in Rice Seedlings Exposed to Aluminum Toxicity and Phosphorus Deficiency

    Directory of Open Access Journals (Sweden)

    Tian-rong GUO

    2012-09-01

    Full Text Available Plants growing in acid soils may suffer both phosphorus (P deficiency and aluminum (Al toxicity. Hydroponic experiments were undertaken to assess the single and combination effects of Al toxicity and low P stress on seedling growth, chlorophyll and proline contents, antioxidative response and lipid peroxidation of two rice genotypes (Yongyou 8 and Xiushui 132 differing in Al tolerance. Al toxicity and P deficiency both inhibited rice seedling growth. The development of toxic symptoms was characterized by reduced chlorophyll content, increased proline and malondialdehyde contents in both roots and leaves, and increased peroxidase and superoxide dismutase activities in roots, but decreased in leaves. The stress condition induced more severe growth inhibition and oxidative stress in Yongyou 8, and Xiushui 132 showed higher tolerance to both Al toxicity and P deficiency. P deficiency aggravated Al toxicity to plant growth and induced more severe lipid peroxidation.

  18. Use of 32P in the study of phosphorus uptake and metabolism in plants

    International Nuclear Information System (INIS)

    Michalik, I.

    1980-01-01

    The method allows following the uptake and metabolism of phosphorus and isolating in acids both soluble organic phosphorus compounds (i.e., esters of phosphoric acid with glycides, free nucleotides, inorganic phosphorus) and insoluble phosphorus compounds (i.e., macromolecular compounds, phospholipids). The method of separating low-molecular and acid-soluble phosphorus compounds by one-dimensional paper chromatography was also tested. In maize roots the following low-molecular phosphorus compounds were determined by autoradiochromatography: ATP, ADP, G-1-P, AMP, G-6-P, di PGA, Ri-5-P, F-1, 6-diP, 3-PGA, Pan. (author)

  19. Experimental assessment of toxic phorbol ester in oil, biodiesel and seed cake of Jatropha curcas and use of biodiesel in diesel engine

    International Nuclear Information System (INIS)

    Prasad, Lalit; Pradhan, Subhalaxmi; Das, L.M.; Naik, S.N.

    2012-01-01

    Highlights: ► In the present study toxic phorbol esters were detected in oil and seed cake of Jatropha curcas but not detected in biodiesel using high performance liquid chromatography (HPLC). ► The quantity of phorbol esters in Jatropha curcas oil and cake were amounted to be 2.12 ± 0.02 mg/g and 0.6 ± 0.01 mg/g respectively. ► As jatropha oil is a potential source for biodiesel preparation, huge amount of oil and cake will be generated and hence need to be handled carefully. ► Upon engine study exhaust pollutant such as hydrocarbon, smoke opacity and carbon monoxide reduced substantially. - Abstract: The present study deals with estimation of toxic phorbol esters in Jatropha curcas oil, cake and biodiesel and performance emission of different blends of biodiesel in diesel engine. The jatropha seed was collected from Chattishgarh, India and oil content of the seed kernel was 56.5%, determined by soxhlet apparatus. The oil was subjected to biodiesel preparation by twin step method of acid esterification followed by alkali transesterification. The total conversion of jatropha oil methyl ester (JOME) after reaction was 96.05% from proton nuclear magnetic resonance ( 1 H NMR) studies. The phorbol esters content of oil, cake and biodiesel was determined by high performance liquid chromatography (HPLC, Waters). The phorbol esters content of the oil was more (2.26 ± 0.01 mg/g) than the cake (0.6 ± 0.01 mg/g) but no phorbol esters peak was detected in biodiesel. The performance and emission study of the fuel blends (JB2, JB5 and JB10) with conventional diesel were tested for their use as substitute fuel for a single cylinder direct injection diesel engine at constant speed (1500 rpm). The emissions such as CO, HC and smoke opacity decreased whereas NO x and BSCF increased with biodiesel blends.

  20. Two-generation reproductive toxicity study of plant stanol esters in rats

    NARCIS (Netherlands)

    Whittaker, M.H.; Frankos, V.H.; Wolterbeek, A.P.M.; Waalkens-Berendsen, D.H.

    1999-01-01

    Plant stanol esters are intended for use as an ingredient in food to reduce the absorption of cholesterol from the gastrointestinal tract. Consumption of plant stanol esters has a demonstrated diet-derived public health benefit, as shown by numerous clinical studies. Plant stanol esters are

  1. Process for uranium recovery in phosphorus compounds

    International Nuclear Information System (INIS)

    Demarthe, J.M.; Solar, Serge.

    1980-01-01

    Process for uranium recovery in phosphorus compounds with an organic phase containing a dialkylphosphoric acid. A solubilizing agent constituted of an heavy alcohol or a phosphoric acid ester or a tertiary phosphine oxide or octanol-2, is added to the organic phase for solubilization of the uranium and ammonium dialkyl pyrophosphate [fr

  2. Toxic effects of several phthalate esters on the embryos and larvae of abalone Haliotis diversicolor supertexta

    Science.gov (United States)

    Yang, Zhihui; Zhang, Xiangjing; Cai, Zhonghua

    2009-05-01

    As the most widely used plasticizers in the world, phthalate esters (PAEs) are potential endocrine disruption compounds (EDCs). In the present study, the toxicity of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), di (2-ethylhexyl) phthalate (DEHP) on embryogenesis and larvae development of the marine univalve Haliotis diversicolor supertexta was examined in laboratory. The results show that the malformation of embryos appeared during the experiment, such as embryos died or lysed, small transparent flocculent rings studded on the periphery of the embryo, and the larvae could failed to hatch. In embryo toxic test, embryos incubated at the highest concentration of DMP, DEP and DBP solutions showed significantly high abnormal rate compared with the control, while DEHP solutions displayed no significant difference. In larval toxic test, in all concentrations of DMP, DEP and DBP solutions, larval settlement rates were low significantly than that of the control. Similarly, DEHP solutions show nearly no effect on the larval settlement. The order of toxicity on embryos and larvae is DBP>DEP>DMP>DEHP. Being a simple and easy stimulation to indoor spawn, sensitive to environmental factors, and short culture time, the embryos of H. diversicolor supertexta can be used to indicate toxicity of the PAEs.

  3. Absence of in vivo genotoxicity of 3-monochloropropane-1,2-diol and associated fatty acid esters in a 4-week comprehensive toxicity study using F344 gpt delta rats.

    Science.gov (United States)

    Onami, Saeko; Cho, Young-Man; Toyoda, Takeshi; Horibata, Katsuyoshi; Ishii, Yuji; Umemura, Takashi; Honma, Masamitsu; Nohmi, Takehiko; Nishikawa, Akiyoshi; Ogawa, Kumiko

    2014-07-01

    3-Monochloropropane-1,2-diol (3-MCPD) is regarded as a rat renal and testicular carcinogen and has been classified as a possible human carcinogen (group 2B) by International Agency for Research on Cancer. This is potentially of great importance given that esters of this compound have recently found to be generated in many foods and food ingredients as a result of food processing. There have been a few reports about their toxicity, although we have recently found that the toxicity profile of 3-MCPD esters was similar to that of 3-MCPD in a rat 13-week repeated dose study, except for the acute renal toxicity seen in 3-MCPD-treated females. In the present study, to examine in vivo genotoxicity we administered equimolar doses of 3-MCPD or 3-MCPD fatty acid esters (palmitate diester, palmitate monoester and oleate diester) to 6-week-old male F344 gpt delta rats carrying a reporter transgene for 4 weeks by intragastric administration. In vivo micronucleus, Pig-a mutation and gpt assays were performed, as well as investigations of major toxicological parameters including histopathological features. As one result, the relative kidney weights of the 3-MCPD and all three ester groups were significantly increased compared with the vehicle control group. However, the frequency of micronucleated reticulocytes and Pig-a mutant red blood cells did not differ among groups. Moreover, no changes were observed in mutant frequencies of gpt and red/gam (Spi(-)) genes in the kidney and the testis of 3-MCPD and 3-MCPD-fatty-acid-esters-treated rats. In histopathological analyses, no treatment related changes were observed, except for decrease of eosinophilic bodies in the kidneys of all treated groups. These results suggest that 3-MCPD and its fatty acid esters are not in vivo genotoxins, although they may exert renal toxicity. © The Author 2014. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society. All rights reserved. For permissions, please e

  4. 13-week oral toxicity study with stanol esters in rats

    NARCIS (Netherlands)

    Turnbull, D.; Whittaker, M.H.; Frankos, V.H.; Jonker, D.

    1999-01-01

    Plant sterols and their saturated derivatives, known as stanols, reduce serum cholesterol when consumed in amounts of approximately 2 g per day. Stanol fatty acid esters have been developed as a highly fat-soluble form that may lower cholesterol more effectively than stanols. Stanol esters occur

  5. Linkage mapping in the oilseed crop Jatropha curcas L. reveals a locus controlling the biosynthesis of phorbol esters which cause seed toxicity

    NARCIS (Netherlands)

    King, A.J.; Montes, L.R.; Clarke, J.G.; Affleck, J.; Li, Y.; Witsenboer, H.; Vossen, van der E.; Linde, van der P.; Tripathi, Y.; Tavares, E.; Shukla, P.; Rajasekaran, T.; Loo, van E.N.; Graham, I.A.

    2013-01-01

    Current efforts to grow the tropical oilseed crop Jatropha curcas L. economically are hampered by the lack of cultivars and the presence of toxic phorbol esters (PE) within the seeds of most provenances. These PE restrict the conversion of seed cake into animal feed, although naturally occurring

  6. Phosphorus dendrimers for nanomedicine.

    Science.gov (United States)

    Caminade, Anne-Marie

    2017-08-31

    From biomaterials to imaging, and from drug delivery to drugs by themselves, phosphorus-containing dendrimers offer a large palette of biological properties, depending essentially on their types of terminal functions. The most salient examples of phosphorus dendrimers used for the elaboration of bio-chips and of supports for cell cultures, for imaging biological events, and for carrying and delivering drugs or biomacromolecules are presented in this feature article. Several phosphorus dendrimers can be considered also as drugs per se (by themselves) in particular to fight against cancers, neurodegenerative diseases, and inflammation, both in vitro and in vivo. Toxicity assays are also reported.

  7. Role of the plasma membrane H(+)-ATPase in the regulation of organic acid exudation under aluminum toxicity and phosphorus deficiency.

    Science.gov (United States)

    Yu, Wenqian; Kan, Qi; Zhang, Jiarong; Zeng, Bingjie; Chen, Qi

    2016-01-01

    Aluminum (Al) toxicity and phosphorus (P) deficiency are 2 major limiting factors for plant growth and crop production in acidic soils. Organic acids exuded from roots have been generally regarded as a major resistance mechanism to Al toxicity and P deficiency. The exudation of organic acids is mediated by membrane-localized OA transporters, such as ALMT (Al-activated malate transporter) and MATE (multidrug and toxic compound extrusion). Beside on up-regulation expression of organic acids transporter gene, transcriptional, translational and post-translational regulation of the plasma membrane H(+)-ATPase are also involved in organic acid release process under Al toxicity and P deficiency. This mini-review summarizes the current knowledge about this field of study on the role of the plasma membrane H(+)-ATPase in organic acid exudation under Al toxicity and P deficiency conditions.

  8. Role of the plasma membrane H+-ATPase in the regulation of organic acid exudation under aluminum toxicity and phosphorus deficiency

    Science.gov (United States)

    Yu, Wenqian; Kan, Qi; Zhang, Jiarong; Zeng, Bingjie; Chen, Qi

    2016-01-01

    Aluminum (Al) toxicity and phosphorus (P) deficiency are 2 major limiting factors for plant growth and crop production in acidic soils. Organic acids exuded from roots have been generally regarded as a major resistance mechanism to Al toxicity and P deficiency. The exudation of organic acids is mediated by membrane-localized OA transporters, such as ALMT (Al-activated malate transporter) and MATE (multidrug and toxic compound extrusion). Beside on up-regulation expression of organic acids transporter gene, transcriptional, translational and post-translational regulation of the plasma membrane H+-ATPase are also involved in organic acid release process under Al toxicity and P deficiency. This mini-review summarizes the current knowledge about this field of study on the role of the plasma membrane H+-ATPase in organic acid exudation under Al toxicity and P deficiency conditions. PMID:26713714

  9. Carboxylesterase-dependent cytotoxicity of dibasic esters (DBE) in rat nasal explants.

    Science.gov (United States)

    Trela, B A; Bogdanffy, M S

    1991-02-01

    Dibasic esters (DBE) are a solvent mixture of dimethyl adipate (DMA), dimethyl glutarate (DMG), and dimethyl succinate (DMS) used in the paint and coating industry. Subchronic inhalation toxicity studies have demonstrated that DBE induce a mild degeneration of the olfactory, but not the respiratory, epithelium of the rat nasal cavity. Carboxylesterase-mediated hydrolysis of the individual dibasic esters is more efficient in olfactory than in respiratory mucosal homogenates. In the present study, an in vitro system of cultured rat nasal explants was utilized to determine if DBE toxicity is dependent on a metabolic activation by nonspecific carboxylesterase. Explants from both the olfactory and the respiratory regions of the female rat nasal cavity were incubated for 2 hr in Williams' medium E containing 10-100 mM DMA, DMG, or DMS. DBE caused a dose-related increase in nasal explant acid phosphatase release, a biochemical index of cytotoxicity. HPLC analysis demonstrated parallel increases in the carboxylesterase-mediated formation of monomethyl ester metabolites. Diacid metabolite production in the nasal explant system was not entirely concentration-dependent. Metabolite concentrations and acid phosphatase release were generally greater in olfactory than respiratory tissues. DBE-induced cytotoxicity and acid metabolite production were markedly attenuated in nasal tissue excised from rats which were pretreated with bis(p-nitrophenyl)phosphate, a carboxylesterase inhibitor. This study presents a viable in vitro method for assessing organic ester cytotoxicity in the rat nasal cavity. It was shown that DBE are weak nasal toxicants under the conditions of this system. It was further demonstrated that DBE toxicity is dependent on a carboxylesterase-mediated activation. A similar mechanism was proposed for the nasal toxicity induced by other organic esters following inhalation exposure.

  10. Synthesis and Antimicrobial Activity of 2-(Aminoacid ester)-3-(6 ...

    African Journals Online (AJOL)

    NJD

    2008-11-06

    Nov 6, 2008 ... synthesized new 6-membered heterocycles in which aminoacid esters are linked to the phosphorus .... analysis run in a 3:7 mixture of ethyl acetate and hexane and the average Rf value observed was 0.75. ..... 7 K.G. Devine, C. McGuigan, T.J. O'Connor, S.R. Nicholis and. D. Kinchington, AIDS, 1990, 4, ...

  11. P(NMe2)3-Mediated Umpolung Alkylation and Nonylidic Olefination of α-Keto Esters.

    Science.gov (United States)

    Wang, Sunewang Rixin; Radosevich, Alexander T

    2015-08-07

    A commercial phosphorus-based reagent (P(NMe2)3) mediates umpolung alkylation of methyl aroylformates with benzylic and allylic bromides, leading to either Barbier-type addition or ylide-free olefination products upon workup. The reaction sequence is initiated by a two-electron redox addition of the tricoordinate phosphorus reagent with an α-keto ester compound (Kukhtin-Ramirez addition). A mechanistic rationale is offered for the chemoselectivity upon which the success of this nonmetal mediated C-C bond forming strategy is based.

  12. Prevention of refinery plugging by residual oil gellant chemicals in crude-optimization of phosphonate ester oil gellants

    Energy Technology Data Exchange (ETDEWEB)

    Lemieux, A.; Alick, C.; Stadnyk, S.; Funkhouser, G.; Fyten, G.; Taylor, R.S. [Halliburton Energy Services, Calgary, AB (Canada); Stemler, P. [Petro-Canada Oil and Gas Inc., Calgary, AB (Canada)

    2005-07-01

    This study examined the use of phosphonate ester oil gellants for refinery plugging. Field tests were performed to test ways to optimize cost and performance and to establish quality control specifications based on performance testing and compositional analysis determined through nuclear magnetic resonance (NMR). Additional field tests were performed to ensure both operational performance and the ability to control volatile phosphorus while continuing to meet the standards of the 2 initial field trials. The study assessed the ability of phosphonate esters to control volatile phosphorus at higher temperatures. Distillations used to evaluate volatile phosphorus to date have had a 250 degree C end point. This temperature was chosen because it represents the approximate temperature experienced at the distillation tower trays where plugging has been observed from components condensing from the gas phase. However, the actual peak temperature in the tower bottom is closer to 350 degrees C. This higher temperature is the actual temperature at which decomposition or volatilization occurs. In order to fully understand the ability to control volatile phosphorus, distillations were conducted with a 350 degree C end point. Volatile and total phosphorus to both 250 degrees C and 350 degrees C end points were reported. The study also addressed the concern regarding organic halide formation under distillation tower conditions, although no organic halides were detected in the field trials. 3 refs., 2 tabs., 7 figs.

  13. On the use of 31P NMR for the quantification of hydrosoluble phosphorus-containing compounds in coral host tissues and cultured zooxanthellae

    Science.gov (United States)

    Godinot, Claire; Gaysinski, Marc; Thomas, Olivier P.; Ferrier-Pagès, Christine; Grover, Renaud

    2016-02-01

    31P Nuclear Magnetic Resonance (NMR) was assessed to investigate the phosphorus-containing compounds present in the tissues of the scleractinian coral Stylophora pistillata as well as of cultured zooxanthellae (CZ). Results showed that phosphorus-containing compounds observed in CZ were mainly phosphate and phosphate esters. Phosphate accounted for 19 ± 2% of the total phosphorus compounds observed in CZ maintained under low P-levels (0.02 μM). Adding 5 mM of dissolved inorganic phosphorus (KH2PO4) to the CZ culture medium led to a 3.1-fold increase in intracellular phosphate, while adding 5 mM of dissolved organic phosphorus led to a reduction in the concentration of phosphorus compounds, including a 2.5-fold intracellular phosphate decrease. In sharp contrast to zooxanthellae, the host mainly contained phosphonates, and to a lesser extent, phosphate esters and phosphate. Two-months of host starvation decreased the phosphate content by 2.4 fold, while bleaching of fed corals did not modify this content. Based on 31P NMR analyses, this study highlights the importance of phosphonates in the composition of coral host tissues, and illustrates the impact of phosphorus availability on the phosphorus composition of host tissues and CZ, both through feeding of the host and inorganic phosphorus enrichment of the CZ.

  14. Yellow phosphorus-induced Brugada phenocopy.

    Science.gov (United States)

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

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

  15. A Comparative Study of the Eco toxicity of Palm-Based Methyl Ester Sulphonates (MES) to Tilapia and Daphnia magna

    International Nuclear Information System (INIS)

    Razmah, G.; Afida, I.S.; Zulina, A.M.; Noorazah, Z.; Hazimah, A.H.

    2016-01-01

    Methyl ester sulphonates (MES) is a surfactant derived from plant resources, suitable as active ingredient in detergents. MES possesses good surface-active properties, good detergency and tolerant to water hardness. In this study, the eco toxicity of MES was evaluated through the 48 hr Daphnia magna immobilisation test and the 96 hr fish acute toxicity test with Tilapia. MES samples with different alkyl chain lengths (C14, C16 and C16:18) produced by the Malaysian Palm Oil Board (MPOB) and commercial MES (C16:18) were tested. Results from all tests indicated that Daphnia was more sensitive to toxic effects from MES than was Tilapia. There is also significant difference in eco toxicity responses for palm-based MES of various chain lengths regardless of the species tested. The eco toxicity increased as the hydrophobicity of the MES increased due to increase of alkyl chain length. However, less than 30 % of MES is used in detergent products and will not pose environmental effects on aquatic organisms. MES is therefore suitable for environmental compatible cleaning products in view of its eco toxicity that is on par to the widely used anionic surfactants, such as linear alkylbenzene sulphonate (LAS). The use of MES in cleaning products may help the industry to fulfil its social responsibility to a cleaner and better environment. (author)

  16. Mechanisms of Phosphine Toxicity

    Directory of Open Access Journals (Sweden)

    Nisa S. Nath

    2011-01-01

    Full Text Available Fumigation with phosphine gas is by far the most widely used treatment for the protection of stored grain against insect pests. The development of high-level resistance in insects now threatens its continued use. As there is no suitable chemical to replace phosphine, it is essential to understand the mechanisms of phosphine toxicity to increase the effectiveness of resistance management. Because phosphine is such a simple molecule (PH3, the chemistry of phosphorus is central to its toxicity. The elements above and below phosphorus in the periodic table are nitrogen (N and arsenic (As, which also produce toxic hydrides, namely, NH3 and AsH3. The three hydrides cause related symptoms and similar changes to cellular and organismal physiology, including disruption of the sympathetic nervous system, suppressed energy metabolism and toxic changes to the redox state of the cell. We propose that these three effects are interdependent contributors to phosphine toxicity.

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

    Science.gov (United States)

    Zechel, David L.; Jochimsen, Bjarne

    2014-01-01

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

  18. A 13-week repeated dose study of three 3-monochloropropane-1,2-diol fatty acid esters in F344 rats.

    Science.gov (United States)

    Onami, Saeko; Cho, Young-Man; Toyoda, Takeshi; Mizuta, Yasuko; Yoshida, Midori; Nishikawa, Akiyoshi; Ogawa, Kumiko

    2014-04-01

    3-monochloropropane-1,2-diol (3-MCPD), a rat renal and testicular carcinogen, has been reported to occur in various foods and food ingredients as free or esterified forms. Since reports about toxicity of 3-MCPD esters are limited, we conducted a 13-week rat subchronic toxicity study of 3-MCPD esters (palmitate diester: CDP, palmitate monoester: CMP, oleate diester: CDO). We administered a carcinogenic dose (3.6 × 10(-4) mol/kg B.W./day) of 3-MCPD or these esters at equimolar concentrations and two 1/4 lower doses by gavage with olive oil as a vehicle five times a week for 13 weeks to F344 male and female rats. As a result, five out of ten 3-MCPD-treated females died from acute renal tubular necrosis, but none of the ester-treated rats. Decreased HGB was observed in all high-dose 3-MCPD fatty acid ester-treated rats, except CDO-treated males. The absolute and relative kidney weights were significantly increased in the ester-treated rats at medium and high doses. Relative liver weights were significantly increased in the esters-treated rat at high dose, except for CMP females. Significant increase in apoptotic epithelial cells in the initial segment of the epididymis of high-dose ester-treated males was also observed. The results suggested that although acute renal toxicity was lower than 3-MCPD, these three 3-MCPD fatty acid esters have the potential to exert subchronic toxicity to the rat kidneys and epididymis, to a similar degree as 3-MCPD under the present conditions. NOAELs (no-observed-adverse-effect levels) of CDP, CMP and CDO were suggested to be 14, 8 and 15 mg/kg B.W./day, respectively.

  19. Diarrhetic shellfish poisoning toxin esters in Danish blue mussels and surf clams

    DEFF Research Database (Denmark)

    Jørgensen, Kevin; Scanlon, Sine Hedegaard; Jensen, L.B.

    2005-01-01

    Until recently, little focus was given to the presence of diarrhetic shellfish poisoning ( DSP) toxin esters in seafood products. However, during the last few years, the occurrence of a high percentage of esters of the total amount of DSP toxins present in some seafood products has been observed....... importance because of the increased use of chemical methods instead of mouse bioassay for the detection of DSP toxicity....

  20. Degradation of phorbol esters by Pseudomonas aeruginosa PseA during solid-state fermentation of deoiled Jatropha curcas seed cake.

    Science.gov (United States)

    Joshi, Chetna; Mathur, Priyanka; Khare, S K

    2011-04-01

    Large amount of seed cake is generated as by-product during biodiesel production from Jatropha seeds. Presence of toxic phorbol esters restricts its utilization as livestock feed. Safe disposal or meaningful utilization of this major by-product necessitates the degradation of these phorbol esters. The present study describes the complete degradation of phorbol esters by Pseudomonas aeruginosa PseA strain during solid state fermentation (SSF) of deoiled Jatropha curcas seed cake. Phorbol esters were completely degraded in nine days under the optimized SSF conditions viz. deoiled cake 5.0 g; moistened with 5.0 ml distilled water; inoculum 1.5 ml of overnight grown P. aeruginosa; incubation at temperature 30 °C, pH 7.0 and RH 65%. SSF of deoiled cake seems a potentially viable approach towards the complete degradation of the toxic phorbol esters. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Biodegradable Poly (Ester Urethane) Urea Biomaterials For Applications in Combat Casualty Care

    National Research Council Canada - National Science Library

    Guelcher, S. A; Sriniwasan, A; Hollinger, J. O

    2006-01-01

    A family of biocompatible, biodegradable poly(ester urethane)urea (PEUUR) biomaterials has been developed that degrade to non-toxic by-products and support the attachment and proliferation of cells...

  2. Remediation of phosphorus from electric furnace waste streams

    International Nuclear Information System (INIS)

    Hanna, J.; Jung, J.O.

    1992-01-01

    Electrothermal production of elemental phosphorus (P4) generates substantial amounts of highly toxic phossy water sludge, slag and other gaseous wastes. Because of their high phosphorus content the sludges pose potential fire hazards. In the absence of a reliable processing technology, large amounts of these hazardous wastes are accumulated at an annual rate of 1.5-2.5 million tons from current and past operations. The accumulated sludges are stored in ponds or in special containment vessels in 30 locations in 18 states including Alabama, California, Tennessee, Idaho and Montana. Serious water pollution problems will result unless these wastes are given extensive treatment to remove the elemental phosphorus. Federal regulations prohibit permanent storage of flammable wastes. This paper reports that recently, researchers at the University of Alabama have developed a two-step method for the treatment of phosphorus sludge that includes bulk removal of phosphorus by physical separation techniques followed by remediation of the residual P4 in the sludge using a novel wet air oxidation technique known as HSAD

  3. Modelling arsenic toxicity in wheat: Simultaneous application of diffusive gradients in thin films to arsenic and phosphorus in soil

    International Nuclear Information System (INIS)

    Mojsilovic, Ognjen; McLaren, Ron G.; Condron, Leo M.

    2011-01-01

    The diffusive gradients in thin films (DGT) technique was evaluated in modelling wheat (Triticum aestivum) arsenic toxicity using a dataset of As-contaminated soil samples (n = 28) collected from former sheep dip sites. Above ground wheat biomass from a 21-day early growth bioassay was adopted as the response variable and the dose-response relationships were modelled using the three-parameter sigmoid equation. The DGT-derived effective soil solution As to P concentration ratios corresponded strongly to the differences in the response variable. With a single sample identified as an outlier, the 95% confidence interval for the effective soil solution As/P molar concentration ratio which resulted in a 50% reduction in the response (EC50) was 0.168-0.360. While the DGT-derived soil measure of As/P ratio was shown as a promising phytotoxicity predictor, the influence of P nutrition on the dose-response relationship deserves further consideration. - Highlights: → We measure the labile As and P in long-term As-contaminated soils using DGT. → We assess soil As toxicity in wheat using an early growth bioassay. → Wheat biomass corresponds strongly to effective soil solution As/P ratio. → Available soil P exhibits an ameliorative effect on As toxicity in wheat. → Response of wheat to available soil As/P ratio appeared sensitive to plant P status. - Diffusive gradient in thin films (DGT) measure of soil arsenic-to-phosphorus ratio provides a promising indicator of arsenic toxicity in wheat.

  4. Modelling arsenic toxicity in wheat: Simultaneous application of diffusive gradients in thin films to arsenic and phosphorus in soil

    Energy Technology Data Exchange (ETDEWEB)

    Mojsilovic, Ognjen, E-mail: ognjen.mojsilovic@ecan.govt.nz [Department of Soil and Physical Sciences, Faculty of Agriculture and Life Sciences, PO Box 84, Lincoln University, Lincoln 7647, Christchurch (New Zealand); McLaren, Ron G., E-mail: ron.mclaren@lincoln.ac.nz [Department of Soil and Physical Sciences, Faculty of Agriculture and Life Sciences, PO Box 84, Lincoln University, Lincoln 7647, Christchurch (New Zealand); Condron, Leo M., E-mail: leo.condron@lincoln.ac.nz [Department of Soil and Physical Sciences, Faculty of Agriculture and Life Sciences, PO Box 84, Lincoln University, Lincoln 7647, Christchurch (New Zealand)

    2011-10-15

    The diffusive gradients in thin films (DGT) technique was evaluated in modelling wheat (Triticum aestivum) arsenic toxicity using a dataset of As-contaminated soil samples (n = 28) collected from former sheep dip sites. Above ground wheat biomass from a 21-day early growth bioassay was adopted as the response variable and the dose-response relationships were modelled using the three-parameter sigmoid equation. The DGT-derived effective soil solution As to P concentration ratios corresponded strongly to the differences in the response variable. With a single sample identified as an outlier, the 95% confidence interval for the effective soil solution As/P molar concentration ratio which resulted in a 50% reduction in the response (EC50) was 0.168-0.360. While the DGT-derived soil measure of As/P ratio was shown as a promising phytotoxicity predictor, the influence of P nutrition on the dose-response relationship deserves further consideration. - Highlights: > We measure the labile As and P in long-term As-contaminated soils using DGT. > We assess soil As toxicity in wheat using an early growth bioassay. > Wheat biomass corresponds strongly to effective soil solution As/P ratio. > Available soil P exhibits an ameliorative effect on As toxicity in wheat. > Response of wheat to available soil As/P ratio appeared sensitive to plant P status. - Diffusive gradient in thin films (DGT) measure of soil arsenic-to-phosphorus ratio provides a promising indicator of arsenic toxicity in wheat.

  5. The effects of physical refining on the formation of 3-monochloropropane-1,2-diol esters in relation to palm oil minor components.

    Science.gov (United States)

    Zulkurnain, Musfirah; Lai, Oi Ming; Latip, Razam Abdul; Nehdi, Imededdine Arbi; Ling, Tau Chuan; Tan, Chin Ping

    2012-11-15

    The formation of 3-monochloropropane-1,2-diol (3-MCPD) esters in refined palm oil during deodorisation is attributed to the intrinsic composition of crude palm oil. Utilising D-optimal design, the effects of the degumming and bleaching processes on the reduction in 3-MCPD ester formation in refined palm oil from poor-quality crude palm oil were studied relative to the palm oil minor components that are likely to be their precursors. Water degumming remarkably reduced 3-MCPD ester formation by up to 84%, from 9.79 mg/kg to 1.55 mg/kg. Bleaching with synthetic magnesium silicate caused a further 10% reduction, to 0.487 mg/kg. The reduction in 3-MCPD ester formation could be due to the removal of related precursors prior to the deodorisation step. The phosphorus content of bleached palm oil showed a significant correlation with 3-MCPD ester formation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. 2-Chloro-1,3-propanediol (2-MCPD) and its fatty acid esters: cytotoxicity, metabolism, and transport by human intestinal Caco-2 cells.

    Science.gov (United States)

    Buhrke, Thorsten; Frenzel, Falko; Kuhlmann, Jan; Lampen, Alfonso

    2015-12-01

    The food contaminants 3-chloro-1,2-propanediol (3-MCPD) and 3-MCPD fatty acid esters have attracted considerable attention in the past few years due to their toxic properties and their occurrence in numerous foods. Recently, significant amounts of the isomeric compounds 2-chloro-1,3-propanediol (2-MCPD) fatty acid esters have been detected in refined oils. Beside the interrogation which toxic effects might be related to the core compound 2-MCPD, the key question from the risk assessment perspective is again-as it was discussed for 3-MCPD fatty acid esters before-to which degree these esters are hydrolyzed in the gut, thereby releasing free 2-MCPD. Here, we show that free 2-MCPD but not 2-MCPD fatty acid esters were able to cross a monolayer of differentiated Caco-2 cells as an in vitro model for the human intestinal barrier. Instead, the esters were hydrolyzed by the cells, thereby releasing free 2-MCPD which was neither absorbed nor metabolized by the cells. Cytotoxicity assays revealed that free 2-MCPD as well as free 3-MCPD was not toxic to Caco-2 cells up to a level of 1 mM, whereas cellular viability was slightly decreased in the presence of a few 2-MCPD and 3-MCPD fatty acid esters at concentrations above 10 µM. The observed cytotoxic effects correlated well with the induction of caspase activity and might be attributed to the induction of apoptosis by free fatty acids which were released from the esters in the presence of Caco-2 cells.

  7. Selenium and phosphorus interaction in pea (pisum sativum L.)

    International Nuclear Information System (INIS)

    Singh, Mahendra; Bhandari, D.K.

    1975-01-01

    The interaction of selenium and phosphorus on the dry matter yield and concentration and uptake of phosphorus, sulfur and selenium was studied in pea (Pisum sativnum) var. T 163. The fertilizer was tagged with P 32 . It was observed that increased concentration of applied selenium in soil decreased the dry matter yield and increased the concentration and uptake of total P, soil P and selenium in pea plants. Increased concentration of P alone increased dry matter yield, concentration and uptake of total, soil and fertilizer P and selenium which was beyond safe limits, and decreased concentration and uptake of sulphur. Selenium and phosphorus showed strong synergetic relationship by increasing the concentration of each other in plants while both showed antagonistic effect on the concentration of sulphur. Phosphorus compensated the toxic effect of selenium and improved the growth and dry matter yield of pea plants. The highest selenium concentration of 22.4 ppm was observed in 100 ppm phosphorus with 5 ppm selenium treated pots while lowest (0.10 ppm) in control. (author)

  8. Promising Low-Toxicity of Viologen-Phosphorus Dendrimers against Embryonic Mouse Hippocampal Cells

    Directory of Open Access Journals (Sweden)

    Jean-Pierre Majoral

    2013-09-01

    Full Text Available A new class of viologen-phosphorus dendrimers (VPDs has been recently shown to possess the ability to inhibit neurodegenerative processes in vitro. Nevertheless, in the Central Nervous Systems domain, there is little information on their impact on cell functions, especially on neuronal cells. In this work, we examined the influence of two VPD (VPD1 and VPD3 of zero generation (G0 on murine hippocampal cell line (named mHippoE-18. Extended analyses of cell responses to these nanomolecules comprised cytotoxicity test, reactive oxygen species (ROS generation studies, mitochondrial membrane potential (ΔΨm assay, cell death detection, cell morphology assessment, cell cycle studies, as well as measurements of catalase (CAT activity and glutathione (GSH level. The results indicate that VPD1 is more toxic than VPD3. However, these two tested dendrimers did not cause a strong cellular response, and induced a low level of apoptosis. Interestingly, VPD1 and VPD3 treatment led to a small decline in ROS level compared to untreated cells, which correlated with slightly increased catalase activity. This result indicates that the VPDs can indirectly lower the level of ROS in cells. Summarising, low-cytotoxicity on mHippoE-18 cells together with their ability to quench ROS, make the VPDs very promising nanodevices for future applications in the biomedical field as nanocarriers and/or drugs per se.

  9. Lead phytotoxicity in soils and nutrient solutions is related to lead induced phosphorus deficiency

    International Nuclear Information System (INIS)

    Cheyns, Karlien; Peeters, Sofie; Delcourt, Dorien; Smolders, Erik

    2012-01-01

    This study was set up to relate lead (Pb) bioavailability with its toxicity to plants in soils. Tomato and barley seedlings were grown in six different PbCl 2 spiked soils (pH: 4.7–7.4; eCEC: 4.2–41.7 cmol c /kg). Soils were leached and pH corrected after spiking to exclude confounding factors. Plant growth was halved at 1600–6500 mg Pb/kg soil for tomato and at 1900–8300 mg Pb/kg soil for barley. These soil Pb threshold were unrelated to soil pH, organic carbon, texture or eCEC and neither soil solution Pb nor Pb 2+ ion activity adequately explained Pb toxicity among soils. Shoot phosphorus (P) concentrations significantly decreased with increasing soil Pb concentrations. Tomato grown in hydroponics at either varying P supply or at increasing Pb (equal initial P) illustrated that shoot P explained growth response in both scenarios. The results suggest that Pb toxicity is partially related to Pb induced P deficiency, likely due to lead phosphate precipitation. - Highlights: ► Tomato and barley shoot growth was affected by Pb toxicity in six different soils. ► Soil properties did not explain differences in plant Pb toxicity among soils. ► Neither soil solution Pb nor Pb 2+ ion activity explained Pb toxicity among soils. ► Shoot phosphorus concentration decreased with increasing soil Pb concentrations. ► Lead induced a P deficiency in plants, likely due to lead phosphate precipitation. - Soil properties did not explain differences in plant lead toxicity among different soils. Shoot phosphorus concentration decreased with increasing soil lead concentrations.

  10. Potential treatments to reduce phorbol esters levels in jatropha seed cake for improving the value added product.

    Science.gov (United States)

    Sadubthummarak, Umapron; Parkpian, Preeda; Ruchirawat, Mathuros; Kongchum, Manoch; Delaune, R D

    2013-01-01

    Jatropha seed cake contains high amounts of protein and other nutrients, however it has a drawback due to toxic compounds. The aim of this study was to investigate the methods applied to detoxify the main toxin, phorbol esters in jatropha seed cake, to a safe and acceptable level by maintaining the nutritional values. Phorbol esters are tetracyclic diterpenoids-polycyclic compounds that are known as tumor promoters and hence exhibited the toxicity within a broad range of species. Mismanagement of the jatropha waste from jatropha oil industries would lead to contamination of the environment, affecting living organisms and human health through the food chain, so several methods were tested for reducing the toxicity of the seed cake. The results from this investigation showed that heat treatments at either 120°C or 220°C for 1 hour and then mixing with adsorbing bentonite (10%), nanoparticles of zinc oxide (100 μg/g) plus NaHCO3 at 4%, followed by a 4-week incubation period yielded the best final product. The remaining phorbol esters concentration (0.05-0.04 mg/g) from this treatment was less than that reported for the nontoxic jatropha varieties (0.11-0.27 mg/g). Nutritional values of the seed cake after treatment remained at the same levels found in the control group and these values were crude protein (20.47-21.40 + 0.17-0.25%), crude lipid (14.27-14.68 + 0.13-0.14%) and crude fiber (27.33-29.67 + 0.58%). A cytotoxicity test conducted using L929 and normal human dermal fibroblast cell lines confirmed that most of the toxic compounds, especially phorbol esters, were shown as completely eliminated. The results suggested that the detoxification of phorbol esters residues in the jatropha seed cake was possible while it also retained nutritional values. Therefore, the methods to detoxify phorbol esters are necessary to minimize the toxicity of jatropha seed cake. Further, it is essential to reduce the possible environmental impacts that may be generated

  11. Final report of the safety assessment of methacrylate ester monomers used in nail enhancement products.

    Science.gov (United States)

    2005-01-01

    Methacrylate ester monomers are used in as artificial nail builders in nail enhancement products. They undergo rapid polymerization to form a hard material on the nail that is then shaped. While Ethyl Methacrylate is the primary monomer used in nail enhancement products, other methacrylate esters are also used. This safety assessment addresses 22 other methacrylate esters reported by industry to be present in small percentages as artificial nail builders in cosmetic products. They function to speed up polymerization and/or form cross-links. Only Tetrahydrofurfuryl Methacrylate was reported to the FDA to be in current use. The polymerization rates of these methacrylate esters are within the same range as Ethyl Methacrylate. While data are not available on all of these methacrylate esters, the available data demonstrated little acute oral, dermal, or i.p. toxicity. In a 28-day inhalation study on rats, Butyl Methacrylate caused upper airway irritation; the NOAEL was 1801 mg/m3. In a 28-day oral toxicity study on rats, t-Butyl Methacrylate had a NOAEL of 20 mg/kg/day. Beagle dogs dosed with 0.2 to 2.0 g/kg/day of C12 to C18 methacrylate monomers for 13 weeks exhibited effects only in the highest dose group: weight loss, emesis, diarrhea, mucoid feces, or salivation were observed. Butyl Methacrylate (0.1 M) and Isobutyl Methacrylate (0.1 M) are mildly irritating to the rabbit eye. HEMA is corrosive when instilled in the rabbit eye, while PEG-4 Dimethacrylate and Trimethylolpropane Trimethacrylate are minimally irritating to the eye. Dermal irritation caused by methacrylates is documented in guinea pigs and rabbits. In guinea pigs, HEMA, Isopropylidenediphenyl Bisglycidyl Methacrylate, Lauryl Methacrylate, and Trimethylolpropane Trimethacrylate are strong sensitizers; Butyl Methacrylate, Cyclohexyl Methacrylate, Hexyl Methacrylate, and Urethane Methacrylate are moderate sensitizers; Hydroxypropyl Methacrylate is a weak sensitizer; and PEG-4 Dimethacrylate and

  12. Reaction of acid esters of methylenebis(phosphonous acid) with carbonyl compounds

    International Nuclear Information System (INIS)

    Novikova, Z.S.; Odinets, I.L.; Lutsenko, I.F.

    1987-01-01

    The reaction of methylenebis(phosphonites) containing two hydrophosphoryl groupings with aliphatic and aromatic aldehydes and ketones in the presence of alkali metal fluorides leads to methylenebis(α-hydroxyalkylphosphinates). The reaction of methylenebis(phosphonites) containing one hydrophosphoryl groupings with carbonyl compounds in the presence of alkali metal fluorides proceeds with the formation of a new type of heterocyclic phosphorus compound, viz., 1,2λ 3 ,4λ 5 -oxadiphospholanes. The reaction of acid esters of methylenebis(phosphonous) acid with carbonyl compounds in the presence of alkali metal alkoxides or a tertiary amine is accompanied by phosphinate-phosphonate rearrangement of the intermediately formed α-hydroxylalkylphosphinates

  13. Solvent Extraction Separation of Phosphorus for the Measurement of 32P

    International Nuclear Information System (INIS)

    Kang, Sang Hoon; Lee, Heung N.; Ahn, Hong Joo; Han, Sun ho; Jee, Kwang Yong

    2006-01-01

    Phosphorus is a major element in life and plays essential roles in the human body. On the other hand, phosphorus organic compound has high toxicity, therefore, the determination of trace amount of phosphorus is important in environment studies. Development of an analytical method for the determination of low levels of phosphorus is very important as a very few analytical techniques yield reliable results for this element at trace levels. Radioactive phosphorus, 32 P (T1/2 = 14.3 d, Emax 1.71 MeV) is the highest energy beta-emitting radionuclides and now generally accepted as an effective therapeutic agent for chronic leukemia and excess red blood cells. But, 32 P used in diagnosis and treatment are generated radioactive waste such as pipette tips, latex gloves, angioplastic balloons, Kimwipes etc.. We'll analyze 32 P in medical radioactive waste in the future. Even if 32 P has low level activity and short halflife, we have to control radioactive materials in medical waste. In this work, experiment separation using solvent extraction of inactive phosphorus as preliminary experiments for the establishment of analysis. Phosphorus is extracted tri-n-octylamine (TNOA)/ xylene, which is the most suitable solvent and then is measured by UV-visable spectrophotometer

  14. Final safety assessment of thiodipropionic acid and its dialkyl esters as used in cosmetics.

    Science.gov (United States)

    Diamante, Catherine; Fiume, Monice Zondlo; Bergfeld, Wilma F; Belsito, Donald V; Hill, Ronald A; Klaassen, Curtis D; Liebler, Daniel C; Marks, James G; Shank, Ronald C; Slaga, Thomas J; Snyder, Paul W; Alan Andersen, F

    2010-07-01

    Dilauryl thiodipropionate (DLTDP), dicetyl thiodipropionate, dimyristyl thiodipropionate, distearyl thiodipropionate, and ditridecyl thiodipropionate are dialkyl esters of their respective alcohols and thiodipropionic acid (TDPA) used in cosmetics. Ingested DLTDP was excreted in the urine as TDPA. Single-dose acute oral and parenteral studies and subchronic and chronic repeated dose oral studies did not suggest significant toxicity. Neither DLTDP nor TDPA was irritating to animal skin or eyes and they were not sensitizers. TDPA was neither a teratogen nor a reproductive toxicant. Genotoxicity studies were negative for TDPA and DLTDP. Clinical testing demonstrated some evidence of irritation but no sensitization or photosensitization. The Cosmetic Ingredient Review Expert Panel considered that the data from DLTDP reasonably may be extrapolated to the other dialkyl esters and concluded that these ingredients were safe for use in cosmetic products that are formulated to be nonirritating.

  15. Solvent Extraction Separation of Phosphorus for the Measurement of {sup 32}P

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Sang Hoon; Lee, Heung N.; Ahn, Hong Joo; Han, Sun ho; Jee, Kwang Yong [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2006-07-01

    Phosphorus is a major element in life and plays essential roles in the human body. On the other hand, phosphorus organic compound has high toxicity, therefore, the determination of trace amount of phosphorus is important in environment studies. Development of an analytical method for the determination of low levels of phosphorus is very important as a very few analytical techniques yield reliable results for this element at trace levels. Radioactive phosphorus, {sup 32}P (T1/2 = 14.3 d, Emax 1.71 MeV) is the highest energy beta-emitting radionuclides and now generally accepted as an effective therapeutic agent for chronic leukemia and excess red blood cells. But, {sup 32}P used in diagnosis and treatment are generated radioactive waste such as pipette tips, latex gloves, angioplastic balloons, Kimwipes etc.. We'll analyze {sup 32}P in medical radioactive waste in the future. Even if {sup 32}P has low level activity and short halflife, we have to control radioactive materials in medical waste. In this work, experiment separation using solvent extraction of inactive phosphorus as preliminary experiments for the establishment of analysis. Phosphorus is extracted tri-n-octylamine (TNOA)/ xylene, which is the most suitable solvent and then is measured by UV-visable spectrophotometer.

  16. Mechanical properties and chemical stability of pivalolactone-based poly(ether ester)s

    NARCIS (Netherlands)

    Tijsma, E.J.; Tijsma, E.J.; van der Does, L.; Bantjes, A.; Bantjes, A.; Vulic, I.

    1994-01-01

    The processing, mechanical and chemical properties of poly(ether ester)s, prepared from pivalolactone (PVL), 1,4-butanediol (4G) and dimethyl terephthalate (DMT), were studied. The poly(ether ester)s could easily be processed by injection moulding, owing to their favourable rheological and thermal

  17. Mapping of QTLs for Seed Phorbol Esters, a Toxic Chemical in Jatropha curcas (L.).

    Science.gov (United States)

    Amkul, Kitiya; Laosatit, Kularb; Somta, Prakit; Shim, Sangrea; Lee, Suk-Ha; Tanya, Patcharin; Srinives, Peerasak

    2017-08-18

    Jatropha ( Jatropha curcas L.) is an oil-bearing plant that has potential to be cultivated as a biodiesel crop. The seed cake after oil extraction has 40-50% protein that can be used in animal feeds. A major limitation in utilizing the cake is the presence of phorbol esters (PE), a heat-tolerant toxic chemical. To identify the quantitative trait loci (QTLs) for PE, we constructed a genetic linkage map from an F₂ population of 95 individuals from a cross "Chai Nat" × "M10" using 143 simple sequence repeat (SSR) markers. M10 is low in seed PE while Chai Nat is high. Seeds from each F₂ individual were quantified for PE content by high performance liquid chromatography. A single marker analysis revealed five markers from linkage group 3 (LG3) and nine markers from LG8 associated with seed PE. Inclusive composite interval mapping identified two QTLs, each on LG3 ( qPE3.1 ) and LG8 ( qPE8.1 ) responsible for the PE. qPE3.1 and qPE8.1 accounted for 14.10%, and 15.49% of total variation in seed PE, respectively. Alelle(s) from M10 at qPE3.1 increased seed PE, while at qPE8.1 decreased seed PE. qPE3.1 is a new loci for PE, while qPE8.1 is the same locus with that reported recently for PE.

  18. Adverse effects induced by ecgonine methyl ester to the zebra mussel: A comparison with the benzoylecgonine

    International Nuclear Information System (INIS)

    Parolini, Marco; Binelli, Andrea

    2013-01-01

    Cocaine and its metabolites are the prevalent psychotropic substances in aquatic environment. However, to date the knowledge on their adverse effects to non-target organisms is inadequate. The aims of this study were to investigate sub-lethal effects induced by the ecgonine methyl ester (EME) to the freshwater bivalve Dreissena polymorpha and to compare its toxicity to that by benzoylecgonine (BE), the other main cocaine metabolite. EME sub-lethal effects were investigated by 14 days in-vivo exposures and a multi-biomarker approach. Slight variations in biomarker responses were found at 0.15 μg/L treatment. 0.5 μg/L EME treatment induced destabilization of lysosome membranes, an overall inactivation of defense enzymes, increases in lipid peroxidation, protein carbonylation and DNA fragmentation, but no variations in fixed genetic damage. The use of a biomarker response index (BRI) showed that at 0.5 μg/L both cocaine metabolites had the same toxicity to zebra mussels specimens. -- Highlights: •Sub-lethal effects induced by ecgonine methyl ester (EME) to D. polymorpha were investigated. •Realistic EME concentrations caused notable adverse effects in treated bivalves. •EME induced oxidative injuries to treated-mussel lipids, protein and DNA. •EME toxicity was comparable to the benzoylecgonine one. -- Environmentally relevant ecgonine methyl ester concentrations induced adverse effects to zebra mussels

  19. Municipal sludge as source of nitrogen and phosphorus in perennial ...

    African Journals Online (AJOL)

    Land application of sludge has been shown to improve soil properties and aid crop growth, but the possibility of constituent nutrients such as nitrogen and phosphorus reaching environmentally toxic levels has caused governing authorities to set limits to how much sludge can be applied to agronomic land. The high nitrogen ...

  20. Chemical decontamination. I. Dephosphorylation of organophosphorus compounds; Decontamination chimique. I. Dephosphorylation des composes organophosphores

    Energy Technology Data Exchange (ETDEWEB)

    Segues, B.; Perez, E.; Rico-Lattes, I.; Riviere, M.; Lattes, A. [Toulouse-3 Univ., 31 (France)

    1996-12-31

    This work describes investigations of methods for the destruction of wastes containing toxic phosphorus esters due to the use of pesticides or chemical weapons. Compounds are destroyed by basic hydrolysis in various structured media (micellar catalysis) in the presence and absence of additives, in both water and mixed micellar media. Different methods are compared and evaluated 40 refs.

  1. Preparation and characterization of a novel hyperbranched polyphosphate ester

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Sufang [College of Chemistry, Chemical Engineering and Material Science, Soochow University, Suzhou, Jiangsu Province 215123 (China); Key Laboratory for Green Chemical Process of Ministry of Education, Wuhan Institute of Technology, Wuhan, Hubei 430073 (China); Zhang, Daohong, E-mail: zhangdh@163.com [Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission and Ministry of Education, South-Central University for Nationalities, Wuhan, Hubei Province 430074 (China); Cheng, Xinjian; Li, Tingcheng; Zhang, Aiqing [Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission and Ministry of Education, South-Central University for Nationalities, Wuhan, Hubei Province 430074 (China); Li, Jinlin [College of Chemistry, Chemical Engineering and Material Science, Soochow University, Suzhou, Jiangsu Province 215123 (China); Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission and Ministry of Education, South-Central University for Nationalities, Wuhan, Hubei Province 430074 (China)

    2012-11-15

    Polyphosphate esters have received a great deal of attention due to their important application in biomaterials field. Hyperbranched structure of polymers may support unique properties, including low viscosity and perfect intrinsic property. We report here three generations of hyperbranched polyphosphate esters (HPPE-1, HPPE-2 and HPPE-3) synthesized from a dehydrochlorination reaction between 1,3,5-tris(2-hydroxyethyl)cyanuric acid (THEIC) and phosphorus oxychloride (POCl{sub 3}), and characterize their chemical structures by FT-IR, {sup 1}H NMR, {sup 13}C NMR, {sup 31}P NMR and 2D NMR ({sup 1}H,{sup 1}H-COSY and {sup 13}C, {sup 1}H-HSQC) techniques. Degrees of branching of HPPE-1, HPPE-2 and HPPE-3 are 0.90, 0.91 and 0.87 respectively from the calculation of their {sup 13}C NMR spectra. Molecular weights of HPPE-1, HPPE-2 and HPPE-3 are m/z 1530, 1768 and 2750 from their MALDI-TOF-MS spectra. Study on thermal degradation mechanism of the HPPE-2 by a 3D FT-IR/TG technology shows that there are two cracking processes of its molecular chains, including the thermal degradation of hydroxylethyl-ended groups, nitrogen heterocycle and -CH{sub 2}CH{sub 2}- groups of HPPE-2. -- Highlights: Black-Right-Pointing-Pointer We prepared three novel hyperbranched polyphosphate esters (HPPE-1, HPPE-2 and HPPE-3). Black-Right-Pointing-Pointer Their chemical structures were characterized by FT-IR, 1D NMR and 2D NMR techniques. Black-Right-Pointing-Pointer Their degrees of branching were over 0.87. Black-Right-Pointing-Pointer TG-FTIR was used to study thermal degradation mechanism of the HPPE-2.

  2. Plasmonic Properties of Silicon Nanocrystals Doped with Boron and Phosphorus.

    Science.gov (United States)

    Kramer, Nicolaas J; Schramke, Katelyn S; Kortshagen, Uwe R

    2015-08-12

    Degenerately doped silicon nanocrystals are appealing plasmonic materials due to silicon's low cost and low toxicity. While surface plasmonic resonances of boron-doped and phosphorus-doped silicon nanocrystals were recently observed, there currently is poor understanding of the effect of surface conditions on their plasmonic behavior. Here, we demonstrate that phosphorus-doped silicon nanocrystals exhibit a plasmon resonance immediately after their synthesis but may lose their plasmonic response with oxidation. In contrast, boron-doped nanocrystals initially do not exhibit plasmonic response but become plasmonically active through postsynthesis oxidation or annealing. We interpret these results in terms of substitutional doping being the dominant doping mechanism for phosphorus-doped silicon nanocrystals, with oxidation-induced defects trapping free electrons. The behavior of boron-doped silicon nanocrystals is more consistent with a strong contribution of surface doping. Importantly, boron-doped silicon nanocrystals exhibit air-stable plasmonic behavior over periods of more than a year.

  3. Liquid Crystalline Thermosets from Ester, Ester-imide, and Ester-amide Oligomers

    Science.gov (United States)

    Dingemans, Theodorus J. (Inventor); Weiser, Erik S. (Inventor); St. Clair, Terry L. (Inventor)

    2009-01-01

    Main chain thermotropic liquid crystal esters, ester-imides, and ester-amides were prepared from AA, BB, and AB type monomeric materials and end-capped with phenylacetylene, phenylmaleimide, or nadimide reactive end-groups. The end-capped liquid crystal oligomers are thermotropic and have, preferably, molecular weights in the range of approximately 1000-15,000 grams per mole. The end-capped liquid crystaloligomers have broad liquid crystalline melting ranges and exhibit high melt stability and very low melt viscosities at accessible temperatures. The end-capped liquid crystal oli-gomers are stable forup to an hour in the melt phase. They are highly processable by a variety of melt process shape forming and blending techniques. Once processed and shaped, the end-capped liquid crystal oigomers were heated to further polymerize and form liquid crystalline thermosets (LCT). The fully cured products are rubbers above their glass transition temperatures.

  4. Ligand-Controlled Chemoselective C(acyl)–O Bond vs C(aryl)–C Bond Activation of Aromatic Esters in Nickel Catalyzed C(sp2)–C(sp3) Cross-Couplings

    KAUST Repository

    Chatupheeraphat, Adisak

    2018-02-20

    A ligand-controlled and site-selective nickel catalyzed Suzuki-Miyaura cross-coupling reaction with aromatic esters and alkyl organoboron reagents as coupling partners was developed. This methodology provides a facile route for C(sp2)-C(sp3) bond formation in a straightforward fashion by successful suppression of the undesired β-hydride elimination process. By simply switching the phosphorus ligand, the ester substrates are converted into the alkylated arenes and ketone products, respectively. The utility of this newly developed protocol was demonstrated by its wide substrate scope, broad functional group tolerance and application in the synthesis of key intermediates for the synthesis of bioactive compounds. DFT studies on the oxidative addition step helped rationalizing this intriguing reaction chemoselectivity: whereas nickel complexes with bidentate ligands favor the C(aryl)-C bond cleavage in the oxidative addition step leading to the alkylated product via a decarbonylative process, nickel complexes with monodentate phosphorus ligands favor activation of the C(acyl)-O bond, which later generates the ketone product.

  5. Enhancing phosphorus removal in constructed wetlands with ochre from mine drainage treatment.

    Science.gov (United States)

    Heal, K V; Dobbie, K E; Bozika, E; McHaffie, H; Simpson, A E; Smith, K A

    2005-01-01

    No single end-use has yet been identified that is capable of consuming the projected production of ochre (mainly iron (III) oxides) from mine drainage treatment. However, the high sorption capacity of ochre for phosphorus (up to 26 mg kg(-1)) means that it could be used in constructed wetlands to enhance phosphorus removal. Laboratory batch experiments showed that coarse-grained ochre removes 90% of all phosphorus forms from sewage effluent after 15 minutes of shaking. From a larger-scale experiment, it is estimated that constructed wetlands with an ochre substrate should remove phosphorus from sewage effluent for up to 200-300 years. The suitability of ochre for phosphorus removal is being investigated at the field scale in a wastewater constructed wetland (175 m2 area) in Berwickshire, UK. The hydraulic and treatment performance of the wetland were monitored for 15 months prior to installation at the inlet in November 2003 of a tank containing approximately 1200 kg ochre. Results so far show that improved hydraulic design is required for ochre to increase the mean phosphorus removal efficiency of the system (27 +/- 28%), but potentially toxic metals (Al, Cd, Cr, Cu, Fe, Ni, Pb, Zn) have not been released from the ochre into the wetland outflow.

  6. [Effects of phosphorus sources on phosphorus fractions in rhizosphere soil of wild barley genotypes with high phosphorus utilization efficiency].

    Science.gov (United States)

    Cai, Qiu-Yan; Zhang, Xi-Zhou; Li, Ting-Xuan; Chen, Guang-Deng

    2014-11-01

    High P-efficiency (IS-22-30, IS-22-25) and low P-efficiency (IS-07-07) wild barley cultivars were chosen to evaluate characteristics of phosphorus uptake and utilization, and properties of phosphorus fractions in rhizosphere and non-rhizosphere in a pot experiment with 0 (CK) and 30 mg P · kg(-1) supplied as only Pi (KH2PO4), only Po (phytate) or Pi + Po (KH2PO4+ phytate). The results showed that dry matter and phosphorus accumulation of wild barley in the different treatments was ranked as Pi > Pi + Po > Po > CK. In addition, dry matter yield and phosphorus uptake of wild barley with high P-efficiency exhibited significantly greater than that with low P-efficiency. The concentration of soil available phosphorus was significantly different after application of different phosphorus sources, which was presented as Pi > Pi + Po > Po. The concentration of soil available phosphorus in high P-efficiency wild barley was significantly higher than that of low P-efficiency in the rhizosphere soil. There was a deficit in rhizosphere available phosphorus of high P-efficiency wild barley, especially in Pi and Pi+Po treatments. The inorganic phosphorus fractions increased with the increasing Pi treatment, and the concentrations of inorganic phosphorus fractions in soil were sorted as follows: Ca10-P > O-P > Fe-P > Al-P > Ca2-P > Ca8-P. The contents of Ca2-P and Ca8-P for high P-efficiency wild barley showed deficits in rhizosphere soil under each phosphorus source treatment. In addition, enrichment of Al-P and Fe-P was observed in Pi treatment in rhizosphere soil. The concentrations of organic phosphorus fractions in soil were sorted as follows: moderate labile organic phosphorus > moderate resistant, resistant organic phosphorus > labile organic phosphorus. The labile and moderate labile organic phosphorus enriched in rhizosphere soil and the greatest enrichment appeared in Pi treatment. Furthermore, the concentrations of moderate resistant organic phosphorus and resistant

  7. Preparation of phosphorus targets using the compound phosphorus nitride

    International Nuclear Information System (INIS)

    Maier-Komor, P.

    1987-01-01

    Commercially available phosphorus nitride (P 3 N 5 ) shows a high oxygen content. Nevertheless, this material is attractive for use as phosphorus targets in experiments where red phosphorus would disappear due to its high vapor pressure and where a metal partner in the phosphide must be excluded due to its high atomic number. Methods are described to produce phosphorus nitride targets by vacuum evaporation condensation. (orig.)

  8. Catalytic Ester to Stannane Functional Group Interconversion via Decarbonylative Cross-Coupling of Methyl Esters

    KAUST Repository

    Yue, Huifeng

    2018-01-03

    An unprecedented conversion of methyl esters to stannanes was realized, providing access to a series of arylstannanes via nickel catalysis. Various common esters including ethyl, cyclohexyl, benzyl, and phenyl esters can undergo the newly developed decarbonylative stannylation reaction. The reaction shows broad substrate scope, can differentiate between different types of esters, and if applied in consecutive fashion, allows the transformation of methyl esters into aryl fluorides or biaryls via fluororination or arylation.

  9. Catalytic Ester to Stannane Functional Group Interconversion via Decarbonylative Cross-Coupling of Methyl Esters

    KAUST Repository

    Yue, Huifeng; Zhu, Chen; Rueping, Magnus

    2018-01-01

    An unprecedented conversion of methyl esters to stannanes was realized, providing access to a series of arylstannanes via nickel catalysis. Various common esters including ethyl, cyclohexyl, benzyl, and phenyl esters can undergo the newly developed decarbonylative stannylation reaction. The reaction shows broad substrate scope, can differentiate between different types of esters, and if applied in consecutive fashion, allows the transformation of methyl esters into aryl fluorides or biaryls via fluororination or arylation.

  10. Effects of protein kinase C activators on phorbol ester-sensitive and -resistant EL4 thymoma cells.

    Science.gov (United States)

    Sansbury, H M; Wisehart-Johnson, A E; Qi, C; Fulwood, S; Meier, K E

    1997-09-01

    Phorbol ester-sensitive EL4 murine thymoma cells respond to phorbol 12-myristate 13-acetate with activation of ERK mitogen-activated protein kinases, synthesis of interleukin-2, and death, whereas phorbol ester-resistant variants of this cell line do not exhibit these responses. Additional aspects of the resistant phenotype were examined, using a newly-established resistant cell line. Phorbol ester induced morphological changes, ERK activation, calcium-dependent activation of the c-Jun N-terminal kinase (JNK), interleukin-2 synthesis, and growth inhibition in sensitive but not resistant cells. A series of protein kinase C activators caused membrane translocation of protein kinase C's (PKCs) alpha, eta, and theta in both cell lines. While PKC eta was expressed at higher levels in sensitive than in resistant cells, overexpression of PKC eta did not restore phorbol ester-induced ERK activation to resistant cells. In sensitive cells, PKC activators had similar effects on cell viability and ERK activation, but differed in their abilities to induce JNK activation and interleukin-2 synthesis. PD 098059, an inhibitor of the mitogen activated protein (MAP)/ERK kinase kinase MEK, partially inhibited ERK activation and completely blocked phorbol ester-induced cell death in sensitive cells. Thus MEK and/or ERK activation, but not JNK activation or interleukin-2 synthesis, appears to be required for phorbol ester-induced toxicity. Alterations in phorbol ester response pathways, rather than altered expression of PKC isoforms, appear to confer phorbol ester resistance to EL4 cells.

  11. Degradation of Jatropha curcas phorbol esters derived from Jatropha oil cake and their tumor-promoting activity.

    Science.gov (United States)

    Nakao, Motoyuki; Hasegawa, Go; Yasuhara, Tadashi; Ishihara, Yoko

    2015-04-01

    Large amount of oil cake is generated during biodiesel production from Jatropha seeds. Although Jatropha oil cake is rich in plant nutrients, presence of toxic phorbol esters restricts the usage of oil cake as a fertilizer. The objective of this study is to evaluate the components and tumor promoting activity of phorbol esters in Jatropha oil cake-supplemented soil and plants grown in the treated soil. Contents and their biological activity of Jatropha phorbol esters in soil and plants were sequentially analyzed by high-performance liquid chromatography (HPLC) and in vitro cell transformation assay, respectively. Disappearance of Jatropha phorbol-ester-specific peaks were followed with HPLC during incubation of Jatropha oil cake with soil for five weeks. Along with the degradation of Jatropha phorbol ester in soil, tumor-promoting activity in the sample was also attenuated and ultimately disappeared. Jatropha phorbol esters and tumor promoting activity were not detected from mustard spinach grown in the Jatropha oil cake-supplemented soil. In addition, the esterase KM109 degrades DHPB (see definition below; Jatropha phorbol ester) and reduced its tumor-promoting activity. From these data, we conclude: (1) components and tumor promoting activity of Jatropha phorbol esters in the oil cake disappeared completely by incubation with soil for five-week, (2) Jatropha phorbol esters did not transfer into plants grown in the Jatropha oil cake-supplemented soil, and (3) DHPB can be degraded by esterase from soil bacterium. These observations are useful for utilization of Jatropha oil cake as a fertilizer. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Sustainable Phosphorus Measures: Strategies and Technologies for Achieving Phosphorus Security

    Directory of Open Access Journals (Sweden)

    Stuart White

    2013-01-01

    Full Text Available Phosphorus underpins the world’s food systems by ensuring soil fertility, maximising crop yields, supporting farmer livelihoods and ultimately food security. Yet increasing concerns around long-term availability and accessibility of the world’s main source of phosphorus—phosphate rock, means there is a need to investigate sustainable measures to buffer the world’s food systems against the long and short-term impacts of global phosphorus scarcity. While the timeline of phosphorus scarcity is contested, there is consensus that more efficient use and recycling of phosphorus is required. While the agricultural sector will be crucial in achieving this, sustainable phosphorus measures in sectors upstream and downstream of agriculture from mine to fork will also need to be addressed. This paper presents a comprehensive classification of all potential phosphorus supply- and demand-side measures to meet long-term phosphorus needs for food production. Examples range from increasing efficiency in the agricultural and mining sector, to technologies for recovering phosphorus from urine and food waste. Such measures are often undertaken in isolation from one another rather than linked in an integrated strategy. This integrated approach will enable scientists and policy-makers to take a systematic approach when identifying potential sustainable phosphorus measures. If a systematic approach is not taken, there is a risk of inappropriate investment in research and implementation of technologies and that will not ultimately ensure sufficient access to phosphorus to produce food in the future. The paper concludes by introducing a framework to assess and compare sustainable phosphorus measures and to determine the least cost options in a given context.

  13. Phosphorus application reduces aluminum toxicity in two Eucalyptus clones by increasing its accumulation in roots and decreasing its content in leaves.

    Science.gov (United States)

    Teng, Weichao; Kang, Yachao; Hou, Wenjuan; Hu, Houzhen; Luo, Wenji; Wei, Jie; Wang, Linghui; Zhang, Boyu

    2018-01-01

    Under acidic conditions, aluminum (Al) toxicity is an important factor limiting plant productivity; however, the application of phosphorus (P) might alleviate the toxic effects of Al. In this study, seedlings of two vegetatively propagated Eucalyptus clones, E. grandis × E. urophylla 'G9' and E. grandis × E. urophylla 'DH32-29'were subjected to six treatments (two levels of Al stress and three levels of P). Under excessive Al stress, root Al content was higher, whereas shoot and leaf Al contents were lower with P application than those without P application. Further, Al accumulation was higher in the roots, but lower in the shoots and leaves of G9 than in those of DH32-29. The secretion of organic acids was higher under Al stress than under no Al stress. Further, under Al stress, the roots of G9 secreted more organic acids than those of DH32-29. With an increase in P supply, Al-induced secretion of organic acids from roots decreased. Under Al stress, some enzymes, including PEPC, CS, and IDH, played important roles in organic acid biosynthesis and degradation. Thus, our results indicate that P can reduce Al toxicity via the fixation of elemental Al in roots and restriction of its transport to stems and leaves, although P application cannot promote the secretion of organic acid anions. Further, the higher Al-resistance of G9 might be attributed to the higher Al accumulation in and organic acid anion secretion from roots and the lower levels of Al in leaves.

  14. Phosphorus application reduces aluminum toxicity in two Eucalyptus clones by increasing its accumulation in roots and decreasing its content in leaves.

    Directory of Open Access Journals (Sweden)

    Weichao Teng

    Full Text Available Under acidic conditions, aluminum (Al toxicity is an important factor limiting plant productivity; however, the application of phosphorus (P might alleviate the toxic effects of Al. In this study, seedlings of two vegetatively propagated Eucalyptus clones, E. grandis × E. urophylla 'G9' and E. grandis × E. urophylla 'DH32-29'were subjected to six treatments (two levels of Al stress and three levels of P. Under excessive Al stress, root Al content was higher, whereas shoot and leaf Al contents were lower with P application than those without P application. Further, Al accumulation was higher in the roots, but lower in the shoots and leaves of G9 than in those of DH32-29. The secretion of organic acids was higher under Al stress than under no Al stress. Further, under Al stress, the roots of G9 secreted more organic acids than those of DH32-29. With an increase in P supply, Al-induced secretion of organic acids from roots decreased. Under Al stress, some enzymes, including PEPC, CS, and IDH, played important roles in organic acid biosynthesis and degradation. Thus, our results indicate that P can reduce Al toxicity via the fixation of elemental Al in roots and restriction of its transport to stems and leaves, although P application cannot promote the secretion of organic acid anions. Further, the higher Al-resistance of G9 might be attributed to the higher Al accumulation in and organic acid anion secretion from roots and the lower levels of Al in leaves.

  15. Adsorption and wettability study of methyl ester sulphonate on precipitated asphaltene

    International Nuclear Information System (INIS)

    Okafor, H E; Gholami, R; Sukirman, Y

    2016-01-01

    Asphaltene precipitation from crude oil and its subsequent aggregation forms solid, which preferentially deposit on rock surfaces causing formation damage and wettability changes leading to loss of crude oil production. To resolve this problem, asphaltene inhibitor has been injected into the formation to prevent the precipitation of asphaltene. Asphaltene inhibitors that are usually employed are generally toxic and non-biodegradable. This paper presents a new environmentally friendly asphaltene inhibitor (methyl ester sulphonate), an anionic surfactant, which has excellent sorption on formation rock surfaces. Result from adsorption study validated by Langmuir and Freundlich models indicate a favourable adsorption. At low volumes injected, methyl ester sulphonate is capable of reverting oil-wet sandstone surface to water-wet surface. Biodegradability test profile shows that for concentrations of 100-5000ppm it is biodegradable by 65-80%. (paper)

  16. Proteomic analysis of 3-MCPD and 3-MCPD dipalmitate toxicity in rat testis.

    Science.gov (United States)

    Sawada, Stefanie; Oberemm, Axel; Buhrke, Thorsten; Meckert, Christine; Rozycki, Christel; Braeuning, Albert; Lampen, Alfonso

    2015-09-01

    Thermal treatment of foodstuff containing fats and salt promotes the formation of 3-chloropropane-1,2-diol (3-MCPD) and its fatty acid esters. 3-MCPD-exposed rats develop testicular lesions and Leydig cell tumors. 3-MCPD and 3-MCPD ester toxicity is thought to be caused by 3-MCPD and its metabolites, since 3-MCPD esters are hydrolyzed in the gut. Inhibition of glycolysis is one of the few known molecular mechanisms of 3-MCPD toxicity. To obtain deeper insight into this process, a comparative proteomic approach was chosen, based on a 28-days repeated-dose feeding study with male Wistar rats. Animals received equimolar doses of 3-MCPD or 3-MCPD dipalmitate. A lower dose of 3-MCPD dipalmitate was also administered. Absence of histopathological changes supported an analysis of early cellular disturbance. Testes were analyzed by two-dimensional gel electrophoresis followed by mass-spectrometric protein identification. Data provide a comprehensive overview of proteomic changes induced by 3-MCPD and 3-MCPD dipalmitate in rat testis in an early phase of organ impairment. Results are compatible with known 3-MCPD effects on reproductive function, substantially extend our knowledge about cellular responses to 3-MCPD and support the hypothesis that toxicity of 3-MCPD and 3-MCPD esters is mediated via common effectors. DJ-1 was identified as a candidate marker for 3-MCPD exposure. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Effect of viologen-phosphorus dendrimers on acetylcholinesterase and butyrylcholinesterase activities.

    Science.gov (United States)

    Ciepluch, Karol; Weber, Monika; Katir, Nadia; Caminade, Anne-Marie; El Kadib, Abdelkrim; Klajnert, Barbara; Majoral, Jean Pierre; Bryszewska, Maria

    2013-03-01

    The inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) is the first step in checking whether new compounds can be considered as drugs for treating neurodegenerative diseases. The effect of viologen-phosphorus dendrimers on AChE and BChE activities was studied. The results show that the effects on the cholinesterase activities depend on dendrimer type and size. Viologen dendrimers can interact with the enzymes in two ways: they can bind either to a peripheral site of the enzyme or to amino acids located near the active site, inhibiting catalysis by both cholinesterases. All tested non-toxic viologen-phosphorus dendrimers inhibited the activities of both cholinesterases, showing their potential as new drugs for treating neurodegenerative diseases. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Effects of nitrate addition on phosphorus retention in an eutrophic reservoir : laboratory experiments

    International Nuclear Information System (INIS)

    Yamada, T.; Janke, H.; Colzato, M.; Beraldo, D.; Mozeto, A.; Botta, C.; Nascimento, M.

    2010-01-01

    The Ibrite reservoir in southeast Brazil is polluted with effluents from an oil refinery as well as domestic untreated sewage from cities in the region. In this study, calcium nitrate was used as a sediment remediation technology in order to reduce phosphorus availability. Experiments were conducted in microcosms incubated for up to 135 days. Ceriodaphnia silvestrii and Vibrio fisheri were used to conduct an acute toxicity assessment of the water column and pore water of the sediments. Chironomus xanthus was used to assess bulk sediments. Results of the chemical analyses showed that high values of acid volatile sulfide in the sediments decreased by 99 per cent after 135 days of incubation. Approximately 50 per cent of the soluble reactive phosphorus was removed from the water column. The toxicity of the tested organisms was attributed to high nitrate concentrations in pore water sediments. Results indicated that calcium nitrate is not suitable as a sediment remediation technology.

  19. Phorbol esters in seed oil of Jatropha curcas L. (saboodam in Thai) and their association with cancer prevention: from the initial investigation to the present topics.

    Science.gov (United States)

    Fujiki, Hirota; Suttajit, Maitree; Rawangkan, Anchalee; Iida, Keisuke; Limtrakul, Pornngarm; Umsumarng, Sonthaya; Suganuma, Masami

    2017-08-01

    In 1988, we first reported the complete chemical structure of a new type of phorbol ester, abbreviated to DHPB, found in seed oil of Jatropha curcas L. (Saboodam in Thai) and its tumor-promoting activity on mouse skin. Although this seed oil contains toxic phorbol ester, it was planned to use it as a feasible renewable oil and the extracted seed cake as fertilizer. This utilization value opened a new science of Jatropha curcas. The main experimental results are cited from our publications, and the relevant literature screened from journals and PubMed. This paper begins with our original work on the structural elucidation of a new phorbol ester, 12-deoxy-16-hydroxyphorbol (DHPB): its tumor-promoting activity was compared with that of TPA. We think that it is timely to review the following research advances with Jatropha curcas, so numerous topics are classified as follows: (1) historical development of phorbol esters in seed oil; (2) toxicity of phorbol ester based on various bioassays; (3) degradation of phorbol ester; (4) a new pharmaceutical compound in seed; and (5) tumor promotion and progression with endogeneous tumor promoters in human carcinogenesis. The discovery of phorbol ester in seed oil raised awareness of the danger of public use of seed oil and seed cake in Thailand, and also indicated the necessity of discussing the concept of primary and tertiary cancer preventions. It is worthwhile to study the future benefits and cancer risks of globally distributed Jatropha curcas L.

  20. Radiation curable coatings containing hydroxy functional polyethers and polyesters of monoethylenic acids or hydroxy esters thereof

    International Nuclear Information System (INIS)

    Kaufman, M.L.

    1978-01-01

    Relatively water insoluble hydroxy functional monoethylenic polyethers or polyesters of monoethylenic carboxylic acids or hydroxy alkyl esters thereof are formed by adducting the monoethylenic acid or its hydroxy ester with an anhydride selected from monoepoxides, lactones, or mixtures thereof in the presence of a Lewis acid catalyst, such as BF 3 etherate, at a temperature below that at which the unsaturation is consumed, typically about 30 to 70 0 C. These adducts are of low volatility and of low toxicity and can be radiation cured in admixture with polyacrylates to form coatings having improved resistance to elevated temperature exposure

  1. Drinking-water-criteria document for phthalic acid esters (PAES). Final report

    International Nuclear Information System (INIS)

    1991-08-01

    The document provides the health effects basis to be considered in establishing the MCLG. To achieve the objective, data on pharmacokinetics human exposure, acute and chronic toxicity to animals and humans, epidemiology and mechanisms of toxicity are evaluated for phthalic acid esters. Specific emphasis is placed on literature data providing dose-response information. Thus, while the literature search and evaluation performed in support of the document has been comprehensive, only the reports considered most pertinent in the derivation of the MCLG are cited in the document. The comprehensive literature data base in support of the document includes information published up to 1986; however, more recent data may have been added during the review process

  2. Esters with water esters 2-c to 6-c

    CERN Document Server

    Getzen, F W; Hefter, G T; Maczynski, Andrzej

    1992-01-01

    This volume is the first of two devoted to esters and water. It includes solubility data for binary systems containing an ester and water up to the end of 1988. The critical evaluations were all prepared by one author and an introductory section has been included to elaborate the philosophy and methodology followed in the evaluations.

  3. Detoxification of toxic phorbol esters from Malaysian Jatropha curcas Linn. kernel by Trichoderma spp. and endophytic fungi.

    Science.gov (United States)

    Najjar, Azhar; Abdullah, Norhani; Saad, Wan Zuhainis; Ahmad, Syahida; Oskoueian, Ehsan; Abas, Faridah; Gherbawy, Youssuf

    2014-02-05

    The presence of phorbol esters (PEs) with toxic properties limits the use of Jatropha curcas kernel in the animal feed industry. Therefore, suitable methods to detoxify PEs have to be developed to render the material safe as a feed ingredient. In the present study, the biological treatment of the extracted PEs-rich fraction with non-pathogenic fungi (Trichoderma harzianum JQ350879.1, T. harzianum JQ517493.1, Paecilomyces sinensis JQ350881.1, Cladosporium cladosporioides JQ517491.1, Fusarium chlamydosporum JQ350882.1, F. chlamydosporum JQ517492.1 and F. chlamydosporum JQ350880.1) was conducted by fermentation in broth cultures. The PEs were detected by liquid chromatography-diode array detector-electrospray ionization mass spectrometry (LC-DAD-ESIMS) and quantitatively monitored by HPLC using phorbol-12-myristate 13-acetate as the standard. At day 30 of incubation, two T. harzianum spp., P. sinensis and C. cladosporioides significantly (p rich fraction for growth. In the cytotoxicity assay, cell viabilities of Chang liver and NIH 3T3 fibroblast cell lines were less than 1% with the untreated PEs-rich fraction, but 84.3%-96.5% with the fungal treated PEs-rich fraction. There was no inhibition on cell viability for normal fungal growth supernatants. To conclude, Trichoderma spp., Paecilomyces sp. and Cladosporium sp. are potential microbes for the detoxification of PEs.

  4. Avocado and olive oil methyl esters

    International Nuclear Information System (INIS)

    Knothe, Gerhard

    2013-01-01

    Biodiesel, the mono-alkyl esters of vegetable oils, animal fats or other triacylglycerol-containing materials and an alternative to conventional petroleum-based diesel fuel, has been derived from a variety of feedstocks. Numerous feedstocks have been investigated as potential biodiesel sources, including commodity oils, however, the methyl esters of avocado and olive oil would likely be suitable as biodiesel fuel. In order to expand the database and comprehensive evaluation of the properties of vegetable oil esters, in this work the fuel-related properties of avocado and olive oil methyl esters, which exhibit similar fatty acid profiles including high oleic acid content, are determined. The cetane numbers of avocado oil methyl esters and olive oil methyl esters are relatively high, determined as 59.2 and 62.5, respectively, due to their elevated content of methyl oleate. Other properties are well within the ranges specified in biodiesel standards. The cloud points of both esters are slightly above 0 °C due to their content of saturated esters, especially methyl palmitate. Overall, avocado and olive oil yield methyl esters with fuel properties comparable to methyl esters from other commodity vegetable oils. The 1 H and 13 C NMR spectra of avocado and olive oil methyl esters are reported. -- Highlights: • Methyl esters of avocado and olive oil meet biodiesel fuel standards. • Provides comparison for methyl esters of other vegetable oils with high oleic content. • Discusses and compares present results with prior literature

  5. Toxicity studies of detoxified Jatropha meal (Jatropha curcas) in rats.

    Science.gov (United States)

    Rakshit, K D; Darukeshwara, J; Rathina Raj, K; Narasimhamurthy, K; Saibaba, P; Bhagya, S

    2008-12-01

    Jatropha curcas, a tropical plant introduced in many Asian and African countries is presently used as a source of biodiesel. The cake after oil extraction is rich in protein and is a potential source of livestock feed. In view of the high toxic nature of whole as well as dehulled seed meal due to the presence of toxic phorbol esters and lectin, the meal was subjected to alkali and heat treatments to deactivate the phorbol ester as well as lectin content. After treatment, the phorbol ester content was reduced up to 89% in whole and dehulled seed meal. Toxicity studies were conducted on male growing rats by feeding treated as well as untreated meal through dietary source. All rats irrespective of treatment had reduced appetite and diet intake was low accompanied by diarrhoea. The rats also exhibited reduced motor activity. The rats fed with treated meals exhibited delayed mortality compared to untreated meal fed rats (p0.02). There were significant changes both in terms of food intake and gain in body weight. Gross examination of vital organs indicated atrophy compared to control casein fed rats. However, histopathological examination of various vital organs did not reveal any treatment related microscopic changes suggesting that the mortality of rats occurred due to lack of food intake, diarrhoea and emaciation. Further studies are in progress for complete detoxification of J. curcas meal for use in livestock feed.

  6. Linkage mapping in the oilseed crop Jatropha curcas L. reveals a locus controlling the biosynthesis of phorbol esters which cause seed toxicity.

    Science.gov (United States)

    King, Andrew J; Montes, Luis R; Clarke, Jasper G; Affleck, Julie; Li, Yi; Witsenboer, Hanneke; van der Vossen, Edwin; van der Linde, Piet; Tripathi, Yogendra; Tavares, Evanilda; Shukla, Parul; Rajasekaran, Thirunavukkarasu; van Loo, Eibertus N; Graham, Ian A

    2013-10-01

    Current efforts to grow the tropical oilseed crop Jatropha curcas L. economically are hampered by the lack of cultivars and the presence of toxic phorbol esters (PE) within the seeds of most provenances. These PE restrict the conversion of seed cake into animal feed, although naturally occurring 'nontoxic' provenances exist which produce seed lacking PE. As an important step towards the development of genetically improved varieties of J. curcas, we constructed a linkage map from four F₂ mapping populations. The consensus linkage map contains 502 codominant markers, distributed over 11 linkage groups, with a mean marker density of 1.8 cM per unique locus. Analysis of the inheritance of PE biosynthesis indicated that this is a maternally controlled dominant monogenic trait. This maternal control is due to biosynthesis of the PE occurring only within maternal tissues. The trait segregated 3 : 1 within seeds collected from F₂ plants, and QTL analysis revealed that a locus on linkage group 8 was responsible for phorbol ester biosynthesis. By taking advantage of the draft genome assemblies of J. curcas and Ricinus communis (castor), a comparative mapping approach was used to develop additional markers to fine map this mutation within 2.3 cM. The linkage map provides a framework for the dissection of agronomic traits in J. curcas, and the development of improved varieties by marker-assisted breeding. The identification of the locus responsible for PE biosynthesis means that it is now possible to rapidly breed new nontoxic varieties. © 2013 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  7. Substoichiometric extraction of phosphorus

    International Nuclear Information System (INIS)

    Shigematsu, T.; Kudo, K.

    1981-01-01

    A study of the substoichiometric extraction of phosphorus is described. Phosphorus was extracted in the form of ternary compounds such as ammonium phosphomolybdate, 8-hydroxyquinolinium phosphomolybdate, tetraphenylarsonium phosphomolybdate and tri-n-octylamine phosphomolybdate. Consequently, phosphorus was extracted substoichiometrically by the addition of a substoichiometric amount of molybdenum for the four phosphomolybdate compounds. On the other hand, phosphorus could be separated substoichiometrically with a substoichiometric amount of tetraphenylarsonium chloride or tri-n-octylamine. Stoichiometric ratios of these ternary compounds obtained substoichiometrically were 1:12:3 for phosphorus, molybdenum and organic reagent. The applicability of these compounds to phosphorus determination is also discussed. (author)

  8. Proteomic analysis of 3-MCPD and 3-MCPD dipalmitate-induced toxicity in rat kidney.

    Science.gov (United States)

    Sawada, Stefanie; Oberemm, Axel; Buhrke, Thorsten; Merschenz, Julia; Braeuning, Albert; Lampen, Alfonso

    2016-06-01

    3-Chloropropane-1,2-diol (3-MCPD) and its fatty acid esters are formed during thermal treatment of fat-containing foodstuff in the presence of salt. Toxicological studies indicate a carcinogenic potential of 3-MCPD, pointing to the kidney as the main target organ. It is assumed that the toxicological property of 3-MCPD esters is constituted by the release of 3-MCPD during digestion. In a repeated-dose 28-day oral toxicity study using Wistar rats, animals were treated with equimolar doses of either 3-MCPD (10 mg/kg body weight) or 3-MCPD dipalmitate (53 mg/kg body weight). A lower dose of 3-MCPD dipalmitate (13.3 mg/kg body weight) was also applied. No histopathologically visible toxicity was observed in the study. To address molecular mechanisms leading to toxicity of 3-MCPD and its esters, kidney samples were analyzed by a comparative, two-dimensional gel electrophoresis/mass spectrometry proteomic approach. After either 3-MCPD or 3-MCPD dipalmitate treatment, alterations in proteins related to various metabolic pathways, including carbohydrate, amino acid, and fatty acid metabolism, were detected. These findings confirm and complement previous data on the inhibition of glucose metabolism by 3-MCPD. Altogether, broad overlap of 3-MCPD- and 3-MCPD dipalmitate-induced proteomic changes was observed. Further analyses revealed that the observed induction of glutathione S-transferase pi 1 (Gstp1) occurred at the transcriptional level and was not related to nuclear factor (erythroid-derived 2)-like 2 activation. Overall, the results indicate common mechanisms of toxicity for 3-MCPD and its dipalmitate ester. Furthermore, data suggest Gstp1 as a sensitive marker for early 3-MCPD-induced effects in rat kidney.

  9. Use of Phosphorus Isotopes for Improving Phosphorus Management in Agricultural Systems

    International Nuclear Information System (INIS)

    2016-10-01

    Phosphorus is an essential element in plant, human and animal nutrition. Soils with low levels of phosphorus are widespread in many regions of the world, and the deficiency limits plant growth and reduces crop production and food quality. This publication provides comprehensive and up to date information on several topics related to phosphorus in soil–plant systems, in agricultural systems and in the environment. It presents the theoretical background as well as practical information on how to use nuclear and radioisotope tracer techniques in both laboratory and greenhouse experiments to assess soil phosphorus forms and plant-available soil phosphorus pools, and to understand the cycling processes in soil–plant systems. The publication focuses on practical applications of radiotracer techniques and can serve as resource material for research projects on improving sustainable phosphorus management in agricultural systems and as practical guidance on the use of phosphate isotopes in soil–plant research

  10. 75 FR 36306 - Chemical Mixtures Containing Listed Forms of Phosphorus and Change in Application Process

    Science.gov (United States)

    2010-06-25

    ... have large industrial uses. Regulated chemical mixtures are not items having common household uses... and others from exposure to the toxic chemicals left behind. Executive Order 12988 This regulation... 1117-AA66 Chemical Mixtures Containing Listed Forms of Phosphorus and Change in Application Process...

  11. Analysis of seed phorbol-ester and curcin content together with genetic diversity in multiple provenances of Jatropha curcas L. from Madagascar and Mexico.

    Science.gov (United States)

    He, Wei; King, Andrew J; Khan, M Awais; Cuevas, Jesús A; Ramiaramanana, Danièle; Graham, Ian A

    2011-10-01

    Jatropha curcas L. has been promoted as an oilseed crop for use to meet the increased world demand for vegetable oil production, and in particular, as a feedstock for biodiesel production. Seed meal is a protein-rich by-product of vegetable oil extraction, which can either be used as an organic fertilizer, or converted to animal feed. However, conversion of J. curcas seed meal into animal feed is complicated by the presence of toxins, though plants producing "edible" or "non-toxic" seeds occur in Mexico. Toxins present in the seeds of J. curcas include phorbol esters and a type-I ribosome inactivating protein (curcin). Although the edible seeds of J. curcas are known to lack phorbol esters, the curcin content of these seeds has not previously been studied. We analyzed the phorbol ester and curcin content of J. curcas seeds obtained from Mexico and Madagascar, and conclude that while phorbol esters are lacking in edible seeds, both types contain curcin. We also analyzed spatial distribution of these toxins in seeds. Phorbol-esters were most concentrated in the tegmen. Curcin was found in both the endosperm and tegmen. We conclude that seed toxicity in J. curcas is likely to be due to a monogenic trait, which may be under maternal control. We also conducted AFLP analysis and conclude that genetic diversity is very limited in the Madagascan collection compared to the Mexican collection. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  12. phosphorus sorption capacity as a guide for phosphorus availability

    African Journals Online (AJOL)

    Prof. Adipala Ekwamu

    drained, light yellowish brown, loamy sand ... Dongola 2 Akked series: Deep, dark grayish brown, clay ... energy. Statistical analysis. Data collected were statistically analysed using ANOVA of MStatc ... phosphorus sorbed versus phosphorus.

  13. Transesterification of rubber seed oil by sonication technique for the production of methyl esters

    Energy Technology Data Exchange (ETDEWEB)

    Ragavan, S.N.; Roy, D.V. [Scott Christian College (Autonomous), Department of Chemistry, Research Centre, Nagercoil, Tamil Nadu (India)

    2011-07-15

    The ever-increasing concern due to the fast-depleting energy sources and the environmental impact of the fossil fuel burning has provoked the researchers to turn out for an environmentally benign fuel source. Biodiesel (fatty acid methyl esters) being renewable, biodegradable, non-toxic and eco-friendly, is now gaining momentum. Added carbon sequestration ability of rubber trees has made it one of the best sources for biodiesel in developing countries. Fatty acid methyl esters (FAMEs) from high acid content (23%) rubber seed oil by sonication technique at room temperature (32 C) is of good yield (80%). The FAMEs produced have acceptable fuel standards as specified by ASTM D 6751. This study deals with the utilisation of FAMEs as an alternate fuel for petrodiesel. (orig.)

  14. Mechanisms and manifestations of toxic actions at the bone tissue level

    International Nuclear Information System (INIS)

    1998-01-01

    The principal abnormalities determined by toxic at the bone level are: osteoporosis, osteomalacia, osteosclerosis or osteopetrosis. The principal toxics having a noxiousness at the bone level are: the fluorine, the phosphorus, the lead, the bismuth, the cadmium and the strontium. The strontium 90 has an important radioactivity that gives at the bone level osteosarcomas or at low doses, leukemoid reactions and marrow angiosarcoma. (N.C.)

  15. High pressure chemistry of red phosphorus by photoactivated simple molecules

    Science.gov (United States)

    Ceppatelli, Matteo; Bini, Roberto; Fanetti, Samuele; Caporali, Maria; Peruzzini, Maurizio

    2013-06-01

    High pressure (HP) is very effective in reducing intermolecular distances and inducing unexpected chemical reactions. In particular the photoactivation of the reactants in HP conditions can lead to very efficient and selective processes. The chemistry of phosphorus is currently based on the white molecular form. The red polymeric allotrope, despite more stable and much less toxic, has not attracted much attention so far. However, switching from the white to the red form would benefit any industrial procedure, especially from an environmental point of view. On the other side, water and ethanol are renewable, environmental friendly and largely available molecules, usable as reactants and photoactivators in HP conditions. Here we report a study on the HP photoinduced reactivity of red phosphorus with water and ethanol, showing the possibility of very efficient and selective processes, leading to molecular hydrogen and valuable phosphorus compounds. The reactions have been studied by means of FTIR and Raman spectroscopy and pressure has been generated using DAC and SAC. HP reactivity has been activated by the two-photon absorption of near-UV wavelengths and occured in total absence of solvents, catalysts and radical initiators, at room T and mild pressure conditions (0.2-1.5 GPa).

  16. α,β-Unsaturated monoterpene acid glucose esters: structural diversity, bioactivities and functional roles.

    Science.gov (United States)

    Goodger, Jason Q D; Woodrow, Ian E

    2011-12-01

    The glycosylation of lipophilic small molecules produces many important plant secondary metabolites. The majority of these are O-glycosides with relatively fewer occurring as glucose esters of aromatic or aliphatic acids. In particular, monoterpene acid glucose esters have much lower structural diversity and distribution compared to monoterpene glycosides. Nevertheless, there have been over 20 monoterpene acid glucose esters described from trees in the genus Eucalyptus (Myrtaceae) in recent years, all based on oleuropeic acid, menthiafolic acid or both. Here we review all of the glucose esters containing these monoterpenoids identified in plants to date. Many of the compounds contain phenolic aglycones and all contain at least one α,β-unsaturated carbonyl, affording a number of important potential therapeutic reactivities such as anti-tumor promotion, carcinogenesis suppression, and anti-oxidant and anti-inflammatory activities. Additional properties such as cytotoxicity, bitterness, and repellency are suggestive of a role in plant defence, but we also discuss their localization to the exterior of foliar secretory cavity lumina, and suggest they may also protect secretory cells from toxic terpenes housed within these structures. Finally we discuss how the use of a recently developed protocol to isolate secretory cavities in a functional state could be used in conjunction with systems biology approaches to help characterize their biosynthesis and roles in plants. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Palladium-catalysed arylation of acetoacetate esters to yield 2-arylacetic acid esters

    CSIR Research Space (South Africa)

    Zeevaart, JG

    2004-05-24

    Full Text Available , was developed simultaneously by Hart- wig and Buchwald.5 Typically the tert-butyl ester of propionic acid is treated with an aryl halide (bromide or chloride) in the presence of a strong base, palladium and a bulky phosphine ligand or a bulky imidazolinium CO2t... novel palladium- catalysed conditions for the arylation of acetoacetate esters resulting in the formation of 2-arylacetic acid esters. When we attempted the arylation of tert-butyl aceto- acetate 1a with bromobenzene 2a using mild reaction conditions (K3...

  18. Light induced degradation of phorbol esters.

    Science.gov (United States)

    Yunping, Bu; Ha, Bui Thi Ngoc; Eunice, Yeo; Chueng, Lo Loong; Yan, Hong

    2012-10-01

    Jatropha curcas (Jatropha) is a tropical shrub that is gaining popularity as a biofuel feedstock plant. Phorbol esters (PEs) are tetracyclic tiglian diterpenoids that are present in Jatropha seeds and other parts of plant. Epidermal cell irritating and cancer promoting PEs not only reduce commercial values of Jatropha seed cake but also cause some safety and environment concerns on PE leaching to soil. A simple bioassay of PE toxicity was conducted by incubating 48 h old brine shrimp (Artemia salina) nauplii with Jatropha oil for 24 h. 1-4% of Jatropha oil (corresponding to PE concentration of 25-100 mg L(-1)) had mortality rate of 5-95%, with LC50 estimated to be 2.7% of oil or 67 mg L(-1) of PE. Jatropha oil was incubated with clay or black soil (autoclaved or non-autoclaved) in the darkness or under sunlight for different periods of time before oil was re-extracted and tested for PE content by HPLC and for remaining toxicity with the brine shrimp bioassay. Under sunlight, PE decreased to non-detectable level within six days. Toxicity reduced to less than 5% mortality rate that is comparable to rapeseed oil control within the same period. In contrast, PE level and toxicity remained little changed when Jatropha oil was incubated in the darkness. Such PE degradation/detoxification was also found independent of the presence of soil or soil microorganisms. We conclude that sunlight directly degrades and detoxifies PEs and this finding should alleviate the concern on long term environmental impact of PE leaching. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Experimental assessment of toxic phytochemicals in Jatropha curcas: oil, cake, bio-diesel and glycerol.

    Science.gov (United States)

    Pradhan, Subhalaxmi; Naik, S N; Khan, M Ashhar I; Sahoo, P K

    2012-02-01

    Jatropha curcas seed is a rich source of oil; however, it can not be utilised for nutritional purposes due to presence of toxic and anti-nutritive compounds. The main objective of the present study was to quantify the toxic phytochemicals present in Indian J. curcas (oil, cake, bio-diesel and glycerol). The amount of phorbol esters is greater in solvent extracted oil (2.8 g kg⁻¹) than in expeller oil (2.1 g kg⁻¹). Liquid chromatography-mass spectroscopy analysis of the purified compound from an active extract of oil confirmed the presence of phorbol esters. Similarly, the phorbol esters content is greater in solvent extracted cake (1.1 g kg⁻¹) than in cake after being expelled (0.8 g kg⁻¹). The phytate and trypsin inhibitory activity of the cake was found to be 98 g kg⁻¹ and 8347 TIU g⁻¹ of cake, respectively. Identification of curcin was achieved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and the concentration of curcin was 0.95 g L⁻¹ of crude concentrate obtained from cake. Higher amounts of phorbol esters are present in oil than cake but bio-diesel and glycerol are free of phorbol esters. The other anti-nutritional components such as trypsin inhibitors, phytates and curcin are present in cake, so the cake should be detoxified before being used for animal feed. Copyright © 2011 Society of Chemical Industry.

  20. Ester Tuiksoo. Proua Suhkru kibedad päevad / Ester Tuiksoo ; interv. Piret Tali

    Index Scriptorium Estoniae

    Tuiksoo, Ester, 1965-

    2005-01-01

    Põllumajandusminister Ester Tuiksoo, kellel peagi täitub ministri ametis aasta Euroopa Liidu suhkrutrahvist, maaettevõtlusest, põllumajandusest, Euroopa Liidu toetustest, ministri elu- ja teenistuskäigust. Lisa: Ester Tuiksoo

  1. Synthetic Methods for Ester Bond Formation and Conformational Analysis of Ester-Containing Carbohydrates

    Science.gov (United States)

    Hackbusch, Sven

    This dissertation encompasses work related to synthetic methods for the formation of ester linkages in organic compounds, as well as the investigation of the conformational influence of the ester functional group on the flexibility of inter-saccharide linkages, specifically, and the solution phase structure of ester-containing carbohydrate derivatives, in general. Stereoselective reactions are an important part of the field of asymmetric synthesis and an understanding of their underlying mechanistic principles is essential for rational method development. Here, the exploration of a diastereoselective O-acylation reaction on a trans-2-substituted cyclohexanol scaffold is presented, along with possible reasons for the observed reversal of stereoselectivity dependent on the presence or absence of an achiral amine catalyst. In particular, this work establishes a structure-activity relationship with regard to the trans-2-substituent and its role as a chiral auxiliary in the reversal of diastereoselectivity. In the second part, the synthesis of various ester-linked carbohydrate derivatives, and their conformational analysis is presented. Using multidimensional NMR experiments and computational methods, the compounds' solution-phase structures were established and the effect of the ester functional group on the molecules' flexibility and three-dimensional (3D) structure was investigated and compared to ether or glycosidic linkages. To aid in this, a novel Karplus equation for the C(sp2)OCH angle in ester-linked carbohydrates was developed on the basis of a model ester-linked carbohydrate. This equation describes the sinusoidal relationship between the C(sp2)OCH dihedral angle and the corresponding 3JCH coupling constant that can be determined from a J-HMBC NMR experiment. The insights from this research will be useful in describing the 3D structure of naturally occurring and lab-made ester-linked derivatives of carbohydrates, as well as guiding the de novo-design of

  2. Environmental effect of rapeseed oil ethyl ester

    International Nuclear Information System (INIS)

    Makareviciene, V.; Janulis, P.

    2003-01-01

    Exhaust emission tests were conducted on rapeseed oil methyl ester (RME), rapeseed oil ethyl ester (REE) and fossil diesel fuel as well as on their mixtures. Results showed that when considering emissions of nitrogen oxides (NO x ), carbon monoxide (CO) and smoke density, rapeseed oil ethyl ester had less negative effect on the environment in comparison with that of rapeseed oil methyl ester. When fuelled with rapeseed oil ethyl ester, the emissions of NO x showed an increase of 8.3% over those of fossil diesel fuel. When operated on 25-50% bio-ester mixed with fossil diesel fuel, NO x emissions marginally decreased. When fuelled with pure rapeseed oil ethyl ester, HC emissions decreased by 53%, CO emissions by 7.2% and smoke density 72.6% when compared with emissions when fossil diesel fuel was used. Carbon dioxide (CO 2 ) emissions, which cause greenhouse effect, decreased by 782.87 g/kWh when rapeseed oil ethyl ester was used and by 782.26 g/kWh when rapeseed oil methyl ester was used instead of fossil diesel fuel. Rapeseed oil ethyl ester was more rapidly biodegradable in aqua environment when compared with rapeseed oil methyl ester and especially with fossil diesel fuel. During a standard 21 day period, 97.7% of rapeseed oil methyl ester, 98% of rapeseed oil ethyl ester and only 61.3% of fossil diesel fuel were biologically decomposed. (author)

  3. Cadmium toxicity to Microcystis aeruginosa PCC 7806 and its microcystin-lacking mutant.

    Directory of Open Access Journals (Sweden)

    Bin Huang

    Full Text Available The adverse effects of microcystin (MC produced by cyanobacteria have drawn considerable attention from the public. Yet it remains unclear whether MC confers any benefits to the cyanobacteria themselves. One suggested function of MC is complexation, which may influence the bioaccumulation and toxicity of trace metals. To test this hypothesis, we examined Cd toxicity to wild-type Microcystis aeruginosa PCC 7806 (WT and its MC-lacking mutant (MT under nutrient-enriched (+NP, phosphorus-limited (-P, and nitrogen-limited (-N conditions. The accumulation of Cd and the biochemical parameters associated with its detoxification [total phosphorus (TP, inorganic polyphosphate (Poly-P, and glutathione (GSH in the cells as well as intra- and extra-cellular carbohydrates] were quantified. Although the -P cyanobacteria accumulated less Cd than their +NP and -N counterparts, the different nutrient-conditioned cyanobacteria were similarly inhibited by similar free ion concentration of Cd in the medium ([Cd2+]F. Such good toxicity predictability of [Cd2+]F was ascribed to the synchronous decrease in the intracellular concentrations of Cd and TP. Nevertheless, Cd toxicity was still determined by the intracellular Cd to phosphorus ratio (Cd/P, in accordance with what has been reported in the literature. On the other hand, the concentrations of TP, Poly-P, and carbohydrates went up, but GSH concentration dropped down with the enhancement of [Cd2+]F, indicating their association with Cd detoxification. Although the inactivation of MC peptide synthetase gene had some nutrient and Cd concentration dependent effects on the parameters above, both cyanobacterial strains showed the same Cd accumulation ability and displayed similar Cd sensitivity. These results suggest that MC cannot affect metal toxicity either by regulating metal accumulation or by altering the detoxification ability of the cyanobacteria. Other possible functions of MC need to be further investigated.

  4. The European source term code ESTER - basic ideas and tools for coupling of ATHLET and ESTER

    International Nuclear Information System (INIS)

    Schmidt, F.; Schuch, A.; Hinkelmann, M.

    1993-04-01

    The French software house CISI and IKE of the University of Stuttgart have developed during 1990 and 1991 in the frame of the Shared Cost Action Reactor Safety the informatic structure of the European Source TERm Evaluation System (ESTER). Due to this work tools became available which allow to unify on an European basis both code development and code application in the area of severe core accident research. The behaviour of reactor cores is determined by thermal hydraulic conditions. Therefore for the development of ESTER it was important to investigate how to integrate thermal hydraulic code systems with ESTER applications. This report describes the basic ideas of ESTER and improvements of ESTER tools in view of a possible coupling of the thermal hydraulic code system ATHLET and ESTER. Due to the work performed during this project the ESTER tools became the most modern informatic tools presently available in the area of severe accident research. A sample application is given which demonstrates the use of the new tools. (orig.) [de

  5. Cobalt-catalyzed hydrogenation of esters to alcohols: unexpected reactivity trend indicates ester enolate intermediacy.

    Science.gov (United States)

    Srimani, Dipankar; Mukherjee, Arup; Goldberg, Alexander F G; Leitus, Gregory; Diskin-Posner, Yael; Shimon, Linda J W; Ben David, Yehoshoa; Milstein, David

    2015-10-12

    The atom-efficient and environmentally benign catalytic hydrogenation of carboxylic acid esters to alcohols has been accomplished in recent years mainly with precious-metal-based catalysts, with few exceptions. Presented here is the first cobalt-catalyzed hydrogenation of esters to the corresponding alcohols. Unexpectedly, the evidence indicates the unprecedented involvement of ester enolate intermediates. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Organic chemistry of elemental phosphorus

    International Nuclear Information System (INIS)

    Milyukov, V A; Budnikova, Yulia H; Sinyashin, Oleg G

    2005-01-01

    The principal achievements and the modern trends in the development of the chemistry of elemental phosphorus are analysed, described systematically and generalised. The possibilities and advantages of the preparation of organophosphorus compounds directly from white phosphorus are demonstrated. Attention is focused on the activation and transformation of elemental phosphorus in the coordination sphere of transition metal complexes. The mechanisms of the reactions of white phosphorus with nucleophilic and electrophilic reagents are discussed. Electrochemical approaches to the synthesis of organic phosphorus derivatives based on white phosphorus are considered.

  7. Transcription profile data of phorbol esters biosynthetic genes during developmental stages in Jatropha curcas.

    Science.gov (United States)

    Jadid, Nurul; Mardika, Rizal Kharisma; Purwani, Kristanti Indah; Permatasari, Erlyta Vivi; Prasetyowati, Indah; Irawan, Mohammad Isa

    2018-06-01

    Jatropha curcas is currently known as an alternative source for biodiesel production. Beside its high free fatty acid content, J. curcas also contains typical diterpenoid-toxic compounds of Euphorbiaceae plant namely phorbol esters. This article present the transcription profile data of genes involved in the biosynthesis of phorbol esters at different developmental stages of leaves, fruit, and seed in Jatropha curcas . Transcriptional profiles were analyzed using reverse transcription-polymerase chain reaction (RT-PCR). We used two genes including GGPPS (Geranylgeranyl diphospate synthase), which is responsible for the formation of common diterpenoid precursor (GGPP) and CS (Casbene Synthase), which functions in the synthesis of casbene. Meanwhile, J. curcas Actin ( ACT ) was used as internal standard. We demonstrated dynamic of GGPPS and CS expression among different stage of development of leaves, fruit and seed in Jatropha .

  8. Degeneration and recovery of rat olfactory epithelium following inhalation of dibasic esters.

    Science.gov (United States)

    Keenan, C M; Kelly, D P; Bogdanffy, M S

    1990-08-01

    Dibasic esters (DBE) are solvent mixtures used in the paint and coating industry. To evaluate the potential subchronic toxicity of DBE, groups of male and female rats were exposed for periods of up to 13 weeks to DBE concentrations of 0, 20, 76, or 390 mg/m3. After approximately 7 and 13 weeks of exposure, 10 rats per sex per group were subjected to clinical chemical, hematological, and urine analyses. Following 7 or 13 weeks of exposure, 10 or 20 rats per sex per group, respectively, were euthanized. An additional 10 rats were euthanized following a 6-week recovery period. A standard profile of tissues, including four levels of nasal cavity, was evaluated histopathologically. After 7 weeks of exposure, slight degeneration of the olfactory epithelium was observed in both male and female rats at 76 and 390 mg/m3. After 13 weeks, degeneration of the olfactory epithelium was present at all DBE concentrations in female rats, but only at the mid and high concentrations in male rats. The severity and incidence of the lesions were concentration related for both sexes with female rats being more sensitive than males. Following the recovery period, histological changes compatible with repair in the olfactory mucosa included an absence of degeneration, focal disorganization of the olfactory epithelium, and respiratory metaplasia. All other tissues were macroscopically normal. No other signs of toxicity were indicated by the other parameters evaluated. Inhalation studies of other esters demonstrate similar pathology in the olfactory epithelium. Since olfactory mucosa is rich in carboxylesterase activity, acids may be the toxic metabolites of these compounds. This hypothetical mechanism may explain the sensitivity of olfactory tissue to the effects of DBE.

  9. Sargasso Sea phosphorus biogeochemistry: an important role for dissolved organic phosphorus (DOP

    Directory of Open Access Journals (Sweden)

    M. W. Lomas

    2010-02-01

    Full Text Available Inorganic phosphorus (SRP concentrations in the subtropical North Atlantic are some of the lowest in the global ocean and have been hypothesized to constrain primary production. Based upon data from several transect cruises in this region, it has been hypothesized that dissolved organic phosphorus (DOP supports a significant fraction of primary production in the subtropical North Atlantic. In this study, a time-series of phosphorus biogeochemistry is presented for the Bermuda Atlantic Time-series Study site, including rates of phosphorus export. Most parameters have a seasonal pattern, although year-over-year variability in the seasonal pattern is substantial, likely due to differences in external forcing. Suspended particulate phosphorus exhibits a seasonal maximum during the spring bloom, despite the absence of a seasonal peak in SRP. However, DOP concentrations are at an annual maximum prior to the winter/spring bloom and decline over the course of the spring bloom while whole community alkaline phosphatase activities are highest. As a result of DOP bioavailability, the growth of particles during the spring bloom occurs in Redfield proportions, though particles exported from the euphotic zone show rapid and significant remineralization of phosphorus within the first 50 m below the euphotic zone. Based upon DOP data from transect cruises in this region, the southward cross gyral flux of DOP is estimated to support ~25% of annual primary production and ~100% of phosphorus export. These estimates are consistent with other research in the subtropical North Atlantic and reinforce the hypothesis that while the subtropics may be phosphorus stressed (a physiological response to low inorganic phosphorus, utilization of the DOP pool allows production and accumulation of microbial biomass at Redfield proportions.

  10. Phosphorus use efficiency of maize: an investigation using radiotracer phosphorus (32P)

    International Nuclear Information System (INIS)

    Meena, S.

    2017-01-01

    A better understanding on the nutrient uptake and utilization by plants is essential for developing better nutrient efficient cultivars suited for optimal production. Precise information on the PUE of crops and P dynamics can be obtained with the help of radiotracer technique. To study the phosphorus acquisition and phosphorus use efficiency of added sources in maize using 32 P, a pot culture experiment was conducted in a medium P soil (21.26 kg ha -1 ). The treatments were P as Single Superphosphate, Enriched FYM with Single Superphosphate (EFYM), DAP, Nutriseed pack (SSP), Nutriseed pack (DAP). The above treatments were applied along with phosphobacteria. Totally there were ten treatments replicated four times. Phosphorus sources were tagged with 32 P (obtained as 32 P in orthophosphoric medium from the Board of Radiation and Isotope Technology) and applied as per the treatments. Radioactive 32 P in the grain and stover sample was determined using Liquid Scintillation Counter (Perkin Elmer Tricarb 2810 R). Using the data, per cent phosphorus derived from fertilizer (%Pdff), per cent phosphorus derived from soil (%Pdfs), Phosphorus Use Efficiency (PUE) and A value were determined. Application of Phosphorus (SSP, DAP, enriched FYM with SSP, Nutriseed pack (SSP) and Nutriseed pack (DAP)) along with PB increased the per cent phosphorus derived from fertilizer (% Pdff), P uptake from fertilizer and PUE. The highest PUE of 25.38 was recorded in the treatment where enriched FYM with SSP was applied along with PB. (author)

  11. Comparison of toxicity of class-based organic chemicals to algae and fish based on discrimination of excess toxicity from baseline level.

    Science.gov (United States)

    Li, Jin J; Tai, Hong W; Yu, Yang; Wen, Yang; Wang, Xiao H; Zhao, Yuan H

    2015-07-01

    Toxicity data to fish and algae were used to investigate excess toxicity between species. Results show that chemicals exhibiting excess toxicity to fish also show excess toxicity to algae for most of the compounds. This indicates that they share the same mode of action between species. Similar relationships between logKOW and toxicities to fish and algae for baseline and less inert compounds suggest that they have similar critical body residues in the two species. Differences in excess toxicity for some compounds suggest that there is a difference of physiological structure and metabolism between fish and algae. Some reactive compounds (e.g. polyamines) exhibit greater toxic effects for algae than those for fish because of relatively low bio-uptake potential of these hydrophilic compounds in fish as compared with that in algae. Esters exhibiting greater toxicity in fish than that in algae indicate that metabolism can affect the discrimination of excess toxicity from baseline level. Algae growth inhibition is a very good surrogate for fish lethality. This is not only because overall toxicity sensitivity to algae is greater than that to fish, but also the excess toxicity calculated from algal toxicity can better reflect reactivity of compounds with target molecules than fish toxicity. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Poly(ester-anhydride):poly(beta-amino ester) micro- and nanospheres: DNA encapsulation and cellular transfection.

    Science.gov (United States)

    Pfeifer, Blaine A; Burdick, Jason A; Little, Steve R; Langer, Robert

    2005-11-04

    Poly(ester-anhydride) delivery devices allow flexibility regarding carrier dimensions (micro- versus nanospheres), degradation rate (anhydride versus ester hydrolysis), and surface labeling (through the anhydride functional unit), and were therefore tested for DNA encapsulation and transfection of a macrophage P388D1 cell line. Poly(l-lactic acid-co-sebacic anhydride) and poly(l-lactic acid-co-adipic anhydride) were synthesized through melt condensation, mixed with 25 wt.% poly(beta-amino ester), and formulated with plasmid DNA (encoding firefly luciferase) into micro- and nanospheres using a double emulsion/solvent evaporation technique. The micro- and nanospheres were then characterized (size, morphology, zeta potential, DNA release) and assayed for DNA encapsulation and cellular transfection over a range of poly(ester-anhydride) copolymer ratios. Poly(ester-anhydride):poly(beta-amino ester) composite microspheres (6-12 microm) and nanospheres (449-1031 nm), generated with copolymers containing between 0 and 25% total polyanhydride content, encapsulated plasmid DNA (>or=20% encapsulation efficiency). Within this polyanhydride range, poly(adipic anhydride) copolymers provided DNA encapsulation at an increased anhydride content (10%, microspheres; 10-25%, nanospheres) compared to poly(sebacic anhydride) copolymers (1%, microspheres and nanospheres) with cellular transfection correlating with the observed DNA encapsulation.

  13. Ashwagandha leaf derived withanone protects normal human cells against the toxicity of methoxyacetic acid, a major industrial metabolite.

    Science.gov (United States)

    Priyandoko, Didik; Ishii, Tetsuro; Kaul, Sunil C; Wadhwa, Renu

    2011-05-04

    The present day lifestyle heavily depends on industrial chemicals in the form of agriculture, cosmetics, textiles and medical products. Since the toxicity of the industrial chemicals has been a concern to human health, the need for alternative non-toxic natural products or adjuvants that serve as antidotes are in high demand. We have investigated the effects of Ayurvedic herb Ashwagandha (Withania somnifera) leaf extract on methoxyacetic acid (MAA) induced toxicity. MAA is a major metabolite of ester phthalates that are commonly used in industry as gelling, viscosity and stabilizer reagents. We report that the MAA cause premature senescence of normal human cells by mechanisms that involve ROS generation, DNA and mitochondrial damage. Withanone protects cells from MAA-induced toxicity by suppressing the ROS levels, DNA and mitochondrial damage, and induction of cell defense signaling pathways including Nrf2 and proteasomal degradation. These findings warrant further basic and clinical studies that may promote the use of withanone as a health adjuvant in a variety of consumer products where the toxicity has been a concern because of the use of ester phthalates.

  14. Ashwagandha leaf derived withanone protects normal human cells against the toxicity of methoxyacetic acid, a major industrial metabolite.

    Directory of Open Access Journals (Sweden)

    Didik Priyandoko

    Full Text Available The present day lifestyle heavily depends on industrial chemicals in the form of agriculture, cosmetics, textiles and medical products. Since the toxicity of the industrial chemicals has been a concern to human health, the need for alternative non-toxic natural products or adjuvants that serve as antidotes are in high demand. We have investigated the effects of Ayurvedic herb Ashwagandha (Withania somnifera leaf extract on methoxyacetic acid (MAA induced toxicity. MAA is a major metabolite of ester phthalates that are commonly used in industry as gelling, viscosity and stabilizer reagents. We report that the MAA cause premature senescence of normal human cells by mechanisms that involve ROS generation, DNA and mitochondrial damage. Withanone protects cells from MAA-induced toxicity by suppressing the ROS levels, DNA and mitochondrial damage, and induction of cell defense signaling pathways including Nrf2 and proteasomal degradation. These findings warrant further basic and clinical studies that may promote the use of withanone as a health adjuvant in a variety of consumer products where the toxicity has been a concern because of the use of ester phthalates.

  15. Detoxification of Toxic Phorbol Esters from Malaysian Jatropha curcas Linn. Kernel by Trichoderma spp. and Endophytic Fungi

    Directory of Open Access Journals (Sweden)

    Azhar Najjar

    2014-02-01

    Full Text Available The presence of phorbol esters (PEs with toxic properties limits the use of Jatropha curcas kernel in the animal feed industry. Therefore, suitable methods to detoxify PEs have to be developed to render the material safe as a feed ingredient. In the present study, the biological treatment of the extracted PEs-rich fraction with non-pathogenic fungi (Trichoderma harzianum JQ350879.1, T. harzianum JQ517493.1, Paecilomyces sinensis JQ350881.1, Cladosporium cladosporioides JQ517491.1, Fusarium chlamydosporum JQ350882.1, F. chlamydosporum JQ517492.1 and F. chlamydosporum JQ350880.1 was conducted by fermentation in broth cultures. The PEs were detected by liquid chromatography-diode array detector-electrospray ionization mass spectrometry (LC-DAD-ESIMS and quantitatively monitored by HPLC using phorbol-12-myristate 13-acetate as the standard. At day 30 of incubation, two T. harzianum spp., P. sinensis and C. cladosporioides significantly (p < 0.05 removed PEs with percentage losses of 96.9%–99.7%, while F. chlamydosporum strains showed percentage losses of 88.9%–92.2%. All fungal strains could utilize the PEs-rich fraction for growth. In the cytotoxicity assay, cell viabilities of Chang liver and NIH 3T3 fibroblast cell lines were less than 1% with the untreated PEs-rich fraction, but 84.3%–96.5% with the fungal treated PEs-rich fraction. There was no inhibition on cell viability for normal fungal growth supernatants. To conclude, Trichoderma spp., Paecilomyces sp. and Cladosporium sp. are potential microbes for the detoxification of PEs.

  16. [Toxicity effects of phthalate substitute plasticizers used in toys].

    Science.gov (United States)

    Hirata-Koizumi, Mutsuko; Takahashi, Mika; Matsumoto, Mariko; Kawamura, Tomoko; Ono, Atsushi; Hirose, Akihiko

    2012-01-01

    Phthalate esters are widely used as plasticizers in polyvinyl chloride products. Because of human health concerns, regulatory authorities in Japan, US, Europe and other countries control the use of di(2-ethylhexyl) phthalate, diisononyl phthalate, di-n-butyl phthalate, butylbenzyl phthalate, diisodecyl phthalate and di-n-octyl phthalate for the toys that can be put directly in infants' mouths. While these regulatory actions will likely reduce the usage of phthalate esters, there is concern that other plasticizers that have not been sufficiently evaluated for safety will be used more frequently. We therefore collected and evaluated the toxicological information on di(2-ethylhexyl) terephthalate (DEHT), 1,2-cyclohexanedicarboxylic acid, diisononyl ester (DINCH), diisononyl adipate (DINA), 2,2,4-trimetyl-1,3-pentanediol diisobutyrate (TXIB), tri-n-butyl citrate (TBC) and acetyl tri-n-butyl citrate (ATBC) which were detected at a relatively high frequency in toys. The collected data have shown that chronic exposure to DEHT affects the eye and nasal turbinate, and DINCH exerts effects on the thyroid and kidney in rats. DINA and TXIB have been reported to have hepatic and renal effects in dogs or rats, and ATBC slightly affected the liver in rats. The NOAELs for repeated dose toxicity are relatively low for DINCH (40 mg/kg bw/day) and TXIB (30 mg/kg bw/day) compared with DEHT, DINA and ATBC. DEHT, TXIB and ATBC have been reported to have reproductive/developmental effects at relatively high doses in rats. For DINA and TBC, available data are insufficient for assessing the hazards, and therefore, adequate toxicity studies should be conducted. In the present review, the toxicity information on 6 alternatives to phthalate plasticizers is summarized, focusing on the effects after oral exposure, which is the route of most concern.

  17. Evaluation of potential effects of soil available phosphorus on soil arsenic availability and paddy rice inorganic arsenic content.

    Science.gov (United States)

    Jiang, Wei; Hou, Qingye; Yang, Zhongfang; Zhong, Cong; Zheng, Guodong; Yang, Zhiqiang; Li, Jie

    2014-05-01

    The transfer of arsenic from paddy field to rice is a major exposure route of the highly toxic element to humans. The aim of our study is to explore the effects of soil available phosphorus on As uptake by rice, and identify the effects of soil properties on arsenic transfer from soil to rice under actual field conditions. 56 pairs of topsoil and rice samples were collected. The relevant parameters in soil and the inorganic arsenic in rice grains were analyzed, and then all the results were treated by statistical methods. Results show that the main factors influencing the uptake by rice grain include soil pH and available phosphorus. The eventual impact of phosphorus is identified as the suppression of As uptake by rice grains. The competition for transporters from soil to roots between arsenic and phosphorus in rhizosphere soil has been a dominant feature. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Towards global phosphorus security: A systems framework for phosphorus recovery and reuse options

    NARCIS (Netherlands)

    Cordell, D.; Rosemarin, A.; Schroder, J.J.; Smit, A.L.

    2011-01-01

    Human intervention in the global phosphorus cycle has mobilised nearly half a billion tonnes of the element from phosphate rock into the hydrosphere over the past half century. The resultant water pollution concerns have been the main driver for sustainable phosphorus use (including phosphorus

  19. Effect of supplemented fungal phytase on performance and phosphorus availability by phosphorus-depleted juvenile rainbow trout (Oncorhynchus mykiss), and on the magnitude and composition of phosphorus waste output

    DEFF Research Database (Denmark)

    Dalsgaard, Anne Johanne Tang; Schøn Ekmann, K.; Pedersen, Per Bovbjerg

    2009-01-01

    The effect of a supplemental fungal phytase on performance and phosphorus availability by juvenile rainbow trout fed diets with a high inclusion of plant based protein and on the magnitude and composition of the waste phosphorus production was tested in a 2 × 3 factorial design at a temperature....../suspended phosphorus waste output from fish fed the phytase supplemented diet containing 0.71% available phosphorus, suggesting that the phosphorus requirement was reached at this phosphorus level. Consistent with this, there was a substantial increase in the dissolved/suspended phosphorus waste output from fish fed...... the phytase supplemented diet containing 0.81% available phosphorus, suggesting that the phosphorus requirement was exceeded in this group. This study demonstrated that phytase supplementation will be advantageous to the fish and the environment if supplemented to low-phosphorus diets containing a large share...

  20. Application conditions for ester cured alkaline phenolic resin sand

    Directory of Open Access Journals (Sweden)

    Ren-he Huang

    2016-07-01

    Full Text Available Five organic esters with different curing speeds: propylene carbonate (i.e. high-speed ester A; 1, 4-butyrolactone; glycerol triacetate (i.e. medium-speed ester B; glycerol diacetate; dibasic ester (DBE (i.e. low-speed ester C, were chosen to react with alkaline phenolic resin to analyze the application conditions of ester cured alkaline phenolic resin. The relationships between the curing performances of the resin (including pH value, gel pH value, gel time of resin solution, heat release rate of the curing reaction and tensile strength of the resin sand and the amount of added organic ester and curing temperature were investigated. The results indicated the following: (1 The optimal added amount of organic ester should be 25wt.%-30wt.% of alkaline phenolic resin and it must be above 20wt.%-50 wt.% of the organic ester hydrolysis amount. (2 High-speed ester A (propylene carbonate has a higher curing speed than 1, 4-butyrolactone, and they were both used as high-speed esters. Glycerol diacetate is not a high-speed ester in alkaline phenolic resin although it was used as a high-speed ester in ester cured sodium silicate sand; glycerol diacetate and glycerol triacetate can be used as medium-speed esters in alkaline phenolic resin. (3 High-speed ester A, medium-speed ester B (glycerol triacetate and low-speed ester C (dibasic ester, i.e., DBE should be used below 15 ìC, 35 ìC and 50 ìC, respectively. High-speed ester A or low-speed ester C should not be used alone but mixed with medium-speed ester B to improve the strength of the resin sand. (4 There should be a suitable solid content (generally 45wt.%-65wt.% of resin, alkali content (generally 10wt.%-15wt.% of resin and viscosity of alkaline phenolic resin (generally 50-300 mPa≤s in the preparation of alkaline phenolic resin. Finally, the technique conditions of alkaline phenolic resin preparation and the application principles of organic ester were discussed.

  1. Microbial Phosphorus Solubilization and Its Potential for Use in Sustainable Agriculture

    Directory of Open Access Journals (Sweden)

    Elizabeth T. Alori

    2017-06-01

    Full Text Available The use of excess conventional Phosphorus (P fertilizers to improve agricultural productivity, in order to meet constantly increasing global food demand, potentially causes surface and ground water pollution, waterway eutrophication, soil fertility depletion, and accumulation of toxic elements such as high concentration of selenium (Se, arsenic (As in the soil. Quite a number of soil microorganisms are capable of solubilizing/mineralizing insoluble soil phosphate to release soluble P and making it available to plants. These microorganisms improve the growth and yield of a wide variety of crops. Thus, inoculating seeds/crops/soil with Phosphate Solubilizing Microorganisms (PSM is a promising strategy to improve world food production without causing any environmental hazard. Despite their great significance in soil fertility improvement, phosphorus-solubilizing microorganisms have yet to replace conventional chemical fertilizers in commercial agriculture. A better understanding of recent developments in PSM functional diversity, colonizing ability, mode of actions and judicious application should facilitate their use as reliable components of sustainable agricultural systems. In this review, we discussed various soil microorganisms that have the ability to solubilize phosphorus and hence have the potential to be used as bio fertilizers. The mechanisms of inorganic phosphate solubilization by PSM and the mechanisms of organic phosphorus mineralization are highlighted together with some factors that determine the success of this technology. Finally we provide some indications that the use of PSM will promote sustainable agriculture and conclude that this technology is ready for commercial exploitation in various regions worldwide.

  2. III. Quantitative aspects of phosphorus excretionin ruminants

    OpenAIRE

    Bravo , David; Sauvant , Daniel; Bogaert , Catherine; Meschy , François

    2003-01-01

    International audience; Ruminant phosphorus excretion and metabolism were studied through a database. Faecal endogenous phosphorus is the main pathway of phosphorus excretion and averages 0.85 of total faecal phosphorus. The remaining 0.15 is unabsorbed dietary phosphorus. Faecal endogenous phosphorus is mainly unabsorbed phosphorus, with saliva being the major source, and is correlated to factors influencing saliva secretion (DM intake, physical dietary characteristics and dietary phosphorus...

  3. Phosphorus blood test

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003478.htm Phosphorus blood test To use the sharing features on this page, please enable JavaScript. The phosphorus blood test measures the amount of phosphate in the blood. ...

  4. Rearrangement of beta,gamma-unsaturated esters with thallium trinitrate: synthesis of indans bearing a beta-keto ester moiety

    Directory of Open Access Journals (Sweden)

    Silva Jr. Luiz F.

    2006-01-01

    Full Text Available The rearrangement of beta,gamma-unsaturated esters, such as 2-(3,4-dihydronaphthalen-1-yl-propionic acid ethyl ester, with thallium trinitrate (TTN in acetic acid leads to 3-indan-1-yl-2-methyl-3-oxo-propionic acid ethyl ester in good yield, through a ring contraction reaction. The new indans thus obtained feature a beta-keto ester moiety, which would be useful for further functionalization.

  5. Screening crops for efficient phosphorus acquisition in a low phosphorus soil using radiotracer technique

    International Nuclear Information System (INIS)

    Meena, S.; Malarvizhi, P.; Rajeswari, R.

    2017-01-01

    Deficiency of phosphorus (P) is the major limitation to agricultural production. Identification of cultivars with greater capacity to grow in soils having low P availability (phosphorus efficiency) will help in P management in a sustainable way. Green house experiment with maize (CO 6) and cotton (MCU 13) as test crops with four levels of phosphorus (0, 3.75, 7.50 and 15 mg P kg -1 soil) was conducted in a P deficient soil (7.2 kg ha -1 ) to study the phosphorus acquisition characteristics and to select efficient crop using 32 P radiotracer technique. Carrier free 32 P obtained as orthophosphoric acid in dilute hydrochloric acid medium from the Board of Radiation and Isotope Technology, Mumbai was used for labeling the soil @ 3200 kBq pot -1 . After 60 days the crops were harvested and the radioactivity was measured in the plant samples using Liquid scintillation counter (PerkinElmer - Tricarb 2810 TR). Different values of specific radioactivity and Isotopically Exchangeable Phosphorus for maize and cotton indicated that chemically different pools of soil P were utilized and maize accessing a larger pool than cotton. Maize having recorded high Phosphorus Use Efficiency, Phosphorus Efficiency and low Phosphorus Stress Factor values, it is a better choice for P deficient soils. Higher Phosphorus Acquisition Efficiency of maize (59 %) than cotton (48%) can be related to the ability of maize to take up P from insoluble inorganic P forms. (author)

  6. Neutral Lipid Biosynthesis in Engineered Escherichia coli: Jojoba Oil-Like Wax Esters and Fatty Acid Butyl Esters

    OpenAIRE

    Kalscheuer, Rainer; Stöveken, Tim; Luftmann, Heinrich; Malkus, Ursula; Reichelt, Rudolf; Steinbüchel, Alexander

    2006-01-01

    Wax esters are esters of long-chain fatty acids and long-chain fatty alcohols which are of considerable commercial importance and are produced on a scale of 3 million tons per year. The oil from the jojoba plant (Simmondsia chinensis) is the main biological source of wax esters. Although it has a multitude of potential applications, the use of jojoba oil is restricted, due to its high price. In this study, we describe the establishment of heterologous wax ester biosynthesis in a recombinant E...

  7. Regioselective Synthesis of Cellulose Ester Homopolymers

    Science.gov (United States)

    Daiqiang Xu; Kristen Voiges; Thomas Elder; Petra Mischnick; Kevin J. Edgar

    2012-01-01

    Regioselective synthesis of cellulose esters is extremely difficult due to the small reactivity differences between cellulose hydroxyl groups, small differences in steric demand between acyl moieties of interest, and the difficulty of attaching and detaching many protecting groups in the presence of cellulose ester moieties without removing the ester groups. Yet the...

  8. Correlation and prediction of mixing thermodynamic properties of ester-containing systems: Ester + alkane and ester + ester binary systems and the ternary dodecane + ethyl pentanoate + ethyl ethanoate

    International Nuclear Information System (INIS)

    Pérez, Noelia; Fernández, Luís; Ortega, Juan; Toledo, Francisco J.; Wisniak, Jaime

    2012-01-01

    Highlights: ► Excess enthalpies and volumes were measured for ester–ester–alkane. ► Mixing behaviour for ester–ester, ester–alkane and ester–ester–alkane are analyzed. ► Correlations with a new polynomial model reproduce well the mixing properties. ► UNIFAC predictions for h E result acceptable excluding the ester–ester mixtures. - Abstract: Excess thermodynamic properties V m E and H m E , have been measured for the ternary mixture dodecane + ethyl pentanoate + ethyl ethanoate and for the corresponding binaries dodecane + ethyl pentanoate, dodecane + ethyl ethanoate, ethyl pentanoate + ethyl ethanoate at 298.15 K. All mixtures show endothermic and expansive effects. Experimental results are correlated with a suitable equation whose final form for the excess ternary quantity M E contains the particular contributions of the three binaries (i–j) and a last term corresponding to the ternary, all of them obtained considering fourth-order interactions. The fit goodness for all mixtures is good and comparable to others equations taken from the literature. In this work the dissolution model for the binaries and ternary is analyzed with a special attention to ester–ester binaries whose behaviour is discussed. The application of the UNIFAC group contribution model to estimate the H m E yields acceptable results for the binaries (with the exception of ester–ester) and for the ternary mixture.

  9. Few-layer black phosphorus nanoparticles.

    Science.gov (United States)

    Sofer, Zdenek; Bouša, Daniel; Luxa, Jan; Mazanek, Vlastimil; Pumera, Martin

    2016-01-28

    Herein, black phosphorus quantum dots and nanoparticles of a few layer thickness were prepared and characterized using STEM, AFM, dynamic light scattering, X-ray photoelectron spectroscopy, X-ray diffraction, Raman spectroscopy and photoluminescence. Impact electrochemistry of the induvidual black phosphorus nanoparticles allows their size determination. The centrifugation of colloidal black phosphorus nanoparticles allowed separation of quantum dots with sizes up to 15 nm. These black phosphorus nanoparticles exhibit a large band gap and are expected to find a wide range of applications from semiconductors to biomolecule tags. The use of black phosphorus nanoparticles for vapour sensing was successfully demonstrated.

  10. Dietary phosphorus acutely impairs endothelial function.

    Science.gov (United States)

    Shuto, Emi; Taketani, Yutaka; Tanaka, Rieko; Harada, Nagakatsu; Isshiki, Masashi; Sato, Minako; Nashiki, Kunitaka; Amo, Kikuko; Yamamoto, Hironori; Higashi, Yukihito; Nakaya, Yutaka; Takeda, Eiji

    2009-07-01

    Excessive dietary phosphorus may increase cardiovascular risk in healthy individuals as well as in patients with chronic kidney disease, but the mechanisms underlying this risk are not completely understood. To determine whether postprandial hyperphosphatemia may promote endothelial dysfunction, we investigated the acute effect of phosphorus loading on endothelial function in vitro and in vivo. Exposing bovine aortic endothelial cells to a phosphorus load increased production of reactive oxygen species, which depended on phosphorus influx via sodium-dependent phosphate transporters, and decreased nitric oxide production via inhibitory phosphorylation of endothelial nitric oxide synthase. Phosphorus loading inhibited endothelium-dependent vasodilation of rat aortic rings. In 11 healthy men, we alternately served meals containing 400 mg or 1200 mg of phosphorus in a double-blind crossover study and measured flow-mediated dilation of the brachial artery before and 2 h after the meals. The high dietary phosphorus load increased serum phosphorus at 2 h and significantly decreased flow-mediated dilation. Flow-mediated dilation correlated inversely with serum phosphorus. Taken together, these findings suggest that endothelial dysfunction mediated by acute postprandial hyperphosphatemia may contribute to the relationship between serum phosphorus level and the risk for cardiovascular morbidity and mortality.

  11. Effect of phosphorus stress on Microcystis aeruginosa growth and phosphorus uptake.

    Directory of Open Access Journals (Sweden)

    Sajeela Ghaffar

    Full Text Available This study was designed to advance understanding of phosphorus regulation of Microcystis aeruginosa growth, phosphorus uptake and storage in changing phosphorus (P conditions as would occur in lakes. We hypothesized that Microcystis growth and nutrient uptake would fit classic models by Monod, Droop, and Michaelis-Menten in these changing conditions. Microcystis grown in luxury nutrient concentrations was transferred to treatments with phosphorus concentrations ranging from 0-256 μg P∙L-1 and luxury nitrogen. Dissolved phosphorus concentration, cell phosphorus quota, P uptake rate and cell densities were measured at day 3 and 6. Results showed little relationship to predicted models. Microcystis growth was asymptotically related to P treatment from day 0-3, fitting Monod model well, but negatively related to P treatment and cell quota from day 3-6. From day 0-3, cell quota was negatively related to P treatments at <2 μg∙L-1, but increased slightly at higher P. Cell quota decreased greatly in low P treatments from day 3-6, which may have enabled high growths in low P treatments. P uptake was positively and linearly related to P treatment during both periods. Negative uptake rates and increases in measured culture phosphorus concentrations to 5 μg∙L-1 in the lowest P treatments indicated P leaked from cells into culture medium. This leakage during early stages of the experiment may have been sufficient to stimulate metabolism and use of intracellular P stores in low P treatments for rapid growth. Our study shows P regulation of Microcystis growth can be complex as a result of changing P concentrations, and this complexity may be important for modeling Microcystis for nutrient and ecosystem management.

  12. Synthesis of 11C labelled methyl esters: transesterification of enol esters versus BF3 catalysed esterification-a comparative study

    International Nuclear Information System (INIS)

    Ackermann, Uwe; Blanc, Paul; Falzon, Cheryl L.; Issa, William; White, Jonathan; Tochon-Danguy, Henri J.; Sachinidis, John I.; Scott, Andrew M.

    2006-01-01

    C-11 labelled methyl esters have been synthesized via the transesterification of enol esters in the presence of C-11 methanol and 1,3 dichlorodibutylstannoxane as catalyst. This method leaves functional groups intact and allows access to a wider variety of C-11 labelled methyl esters compared to the BF 3 catalysed ester formation, which uses carboxylic acids and C-11 methanol as starting materials

  13. Synthesis, Crystal Structure and Biological Activities of Novel Anthranilic(Isophthalic) Acid Esters

    Institute of Scientific and Technical Information of China (English)

    YAN Tao; YU Guan-ping; LIU Peng-fei; XIONG Li-xia; YU Shu-jing; LI Zheng-ming

    2012-01-01

    In search of environmentally benign insecticides with high activity,low toxicity and low resistance,a series of novel anthranilic(isophthalic) acid esters was designed and synthesized based on the structure of ryanodine modulating agent.All the compounds were characterized by 1H NMR spectra,elemental analysis or high resolution mass spectrometry(HRMS).The preliminary results of biological activity assessment indicate that some of the title compounds exhibit certain but unremarkable insecticidal activity against Mythimna separata Walker at 200 mg/L and fungicidal activities against five funguses at 50 mg/L.

  14. High pressure chemistry of red phosphorus by photo-activated simple molecules

    Science.gov (United States)

    Ceppatelli, M.; Fanetti, S.; Bini, R.; Caporali, M.; Peruzzini, M.

    2014-05-01

    High pressure (HP) is very effective in reducing intermolecular distances and inducing unexpected chemical reactions. In addition the photo-activation of the reactants in HP conditions can lead to very efficient and selective processes. The chemistry of phosphorus is currently based on the white molecular form. The red polymeric allotrope, despite more stable and much less toxic, has not attracted much attention so far. However, switching from the white to the red form would benefit any industrial procedure, especially from an environmental point of view. On the other side, water and ethanol are renewable, environmental friendly and largely available molecules, usable as reactants and photo-activators in HP conditions. Here we report a study on the HP photo-induced reactivity of red phosphorus with water and ethanol, showing the possibility of very efficient and selective processes, leading to molecular hydrogen and valuable phosphorus compounds. The reactions have been studied by means of FTIR and Raman spectroscopy and pressure has been generated using membrane Diamond (DAC) and Sapphire (SAC) anvil cells. HP reactivity has been activated by the two-photon absorption of near-UV wavelengths and occurred in total absence of solvents, catalysts and radical initiators, at room T and mild pressure conditions (0.2-1.5 GPa).

  15. High pressure chemistry of red phosphorus by photo-activated simple molecules

    International Nuclear Information System (INIS)

    Ceppatelli, M; Bini, R; Caporali, M; Peruzzini, M; Fanetti, S

    2014-01-01

    High pressure (HP) is very effective in reducing intermolecular distances and inducing unexpected chemical reactions. In addition the photo-activation of the reactants in HP conditions can lead to very efficient and selective processes. The chemistry of phosphorus is currently based on the white molecular form. The red polymeric allotrope, despite more stable and much less toxic, has not attracted much attention so far. However, switching from the white to the red form would benefit any industrial procedure, especially from an environmental point of view. On the other side, water and ethanol are renewable, environmental friendly and largely available molecules, usable as reactants and photo-activators in HP conditions. Here we report a study on the HP photo-induced reactivity of red phosphorus with water and ethanol, showing the possibility of very efficient and selective processes, leading to molecular hydrogen and valuable phosphorus compounds. The reactions have been studied by means of FTIR and Raman spectroscopy and pressure has been generated using membrane Diamond (DAC) and Sapphire (SAC) anvil cells. HP reactivity has been activated by the two-photon absorption of near-UV wavelengths and occurred in total absence of solvents, catalysts and radical initiators, at room T and mild pressure conditions (0.2–1.5 GPa).

  16. Neutral lipid biosynthesis in engineered Escherichia coli: jojoba oil-like wax esters and fatty acid butyl esters.

    Science.gov (United States)

    Kalscheuer, Rainer; Stöveken, Tim; Luftmann, Heinrich; Malkus, Ursula; Reichelt, Rudolf; Steinbüchel, Alexander

    2006-02-01

    Wax esters are esters of long-chain fatty acids and long-chain fatty alcohols which are of considerable commercial importance and are produced on a scale of 3 million tons per year. The oil from the jojoba plant (Simmondsia chinensis) is the main biological source of wax esters. Although it has a multitude of potential applications, the use of jojoba oil is restricted, due to its high price. In this study, we describe the establishment of heterologous wax ester biosynthesis in a recombinant Escherichia coli strain by coexpression of a fatty alcohol-producing bifunctional acyl-coenzyme A reductase from the jojoba plant and a bacterial wax ester synthase from Acinetobacter baylyi strain ADP1, catalyzing the esterification of fatty alcohols and coenzyme A thioesters of fatty acids. In the presence of oleate, jojoba oil-like wax esters such as palmityl oleate, palmityl palmitoleate, and oleyl oleate were produced, amounting to up to ca. 1% of the cellular dry weight. In addition to wax esters, fatty acid butyl esters were unexpectedly observed in the presence of oleate. The latter could be attributed to solvent residues of 1-butanol present in the medium component, Bacto tryptone. Neutral lipids produced in recombinant E. coli were accumulated as intracytoplasmic inclusions, demonstrating that the formation and structural integrity of bacterial lipid bodies do not require specific structural proteins. This is the first report on substantial biosynthesis and accumulation of neutral lipids in E. coli, which might open new perspectives for the biotechnological production of cheap jojoba oil equivalents from inexpensive resources employing recombinant microorganisms.

  17. Ester Tuiksoo / Ester Tuiksoo ; interv. Piret Tali

    Index Scriptorium Estoniae

    Tuiksoo, Ester, 1965-

    2007-01-01

    Juhan Partsi valitsuse (05.04.2004-13.04.2005) ja Andrus Ansipi valitsuse (13.04.2005-) põllumajandusminister Ester Tuiksoo oma lapsepõlvest ja elukutsevalikust, poliitilise karjääri algusest ja erakonna valikust, ministritöö kogemustest, naistest poliitikas

  18. Study of the Transformation of the Oil of Used Soya in Fatty Acid Ethyl Ester

    Directory of Open Access Journals (Sweden)

    Anabel Sarracent-López

    2016-07-01

    Full Text Available The reuse of vegetable oils in food processing brings harmful health effects and on the other hand needs a complex treatment to discard without affecting the environment. Transformed into methyl or ethyl esters of fatty acids and glycerin by transesterification with the corresponding alcohol, can be a suitable method for treatment. It was investigated residual soybean oil from a producer of fried foods and ethanol. It is known that with this spirit the transformation process presents difficulties not listed with methanol, but at the same time does not bring the drawbacks of the latter, for toxicity and acquisition, and that since it is a derivative of the domestic sugar industry does not constitute a raw material import. We experimented with ethanol 80 %, 85 % and 90 % purity and worked 35 ºC and 50 ºC. Final yields of ethyl esters, are low compared with those obtained for similar processes with methanol, 85 % being the highest yield obtained under the conditions of the process. An assessment of costs was conducted to produce 1L of ethyl esters in the laboratory, the expenses of 0,56 pesos/L.

  19. Phosphorus in Agriculture : 100 % Zero

    NARCIS (Netherlands)

    Schnug, Ewald; De Kok, Luit J.

    2016-01-01

    Phosphorus is essential for all living organisms, reserves in geogenic deposits are finite, and phosphorus nutrient mining and oversupply are common phenomenons on agricultural soils. Only if the agricultural phosphorus cycle can be closed and the fertilized nutrient been utilized completely,

  20. Anticholinesterase activity of fluorochloronitroacetic acid esters

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, Yu.Ya.; Brel, V.K. Martynov, I.V.

    1984-11-01

    Results are presented from pharmacologic and biochemical experiments leading to the conclusion that fluorochloronitroacetic acid esters have anticholinesterase activity. Since the esters caused muscular weakness in mice, experiments were performed on isolated tissue preparation. The biochemical experiments consisted of finding the biomolecular constants of irreversible inhibition of acetylcholinesterase by the esters, using acetylcholinesterase from human erythrocytes, as well as horse serum cholinesterase. The ethyl and n-propyl esters of halogen nitroacetic acid were used in all experiments. It was found that the propyl ester caused an increase in the force of individual contractions in the isolated muscle specimens, plus an inability of the muscle to retain tetanus. The substances were determined to have an anticholinesterase effect. The mechanism of cholinesterase inhibition is not yet known. It is probable that the substances acylate the serine hydroxyl of the esterase center of the cholinestersase. 7 references, 1 figure.

  1. Synergistic Effect of Nanosilica Aerogel with Phosphorus Flame Retardants on Improving Flame Retardancy and Leaching Resistance of Wood

    Directory of Open Access Journals (Sweden)

    Xiaodan Zhu

    2014-01-01

    Full Text Available Nanosilica (Nano-SiO2 sol fabricated by a sol-gel process was introduced into wood modification with phosphorus flame retardants to improve the flame retardancy and leaching resistance of wood. The obtained materials were characterized by scanning electron microscopy and energy dispersive spectrometer (SEM-EDS, thermogravimetric analysis (TGA, cone calorimetric (CONE, and infrared spectroscopy (FT-IR. The residual rate of flame retardants before and after leaching was determinated by a leaching resistance. The results showed that the phosphorus flame retardants and SiO2 sol could reside in the poplar wood and are widely distributed in the vessels, pits, wood timber, and the spaces between wood cells of poplar substrate. TGA and CONE results indicated that the introduction of nano-SiO2 aerogel with phosphorus flame retardants had a significantly synergistic effect on improving the flame retardancy and inhibiting the release of smoke and toxic gases. In addition, the leaching resistance test, combined with infrared analysis and EDS analysis, confirmed that the phosphorus flame retardants were able to be fixed by SiO2 aerogel in the wood.

  2. Phosphorus poisoning in waterfowl

    Science.gov (United States)

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

    1950-01-01

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

  3. Phosphorus oxide gate dielectric for black phosphorus field effect transistors

    Science.gov (United States)

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

    2018-04-01

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

  4. Sewage-effluent phosphorus: A greater risk to river eutrophication than agricultural phosphorus?

    International Nuclear Information System (INIS)

    Jarvie, Helen P.; Neal, Colin; Withers, Paul J.A.

    2006-01-01

    Phosphorus (P) concentrations from water quality monitoring at 54 UK river sites across seven major lowland catchment systems are examined in relation to eutrophication risk and to the relative importance of point and diffuse sources. The over-riding evidence indicates that point (effluent) rather than diffuse (agricultural) sources of phosphorus provide the most significant risk for river eutrophication, even in rural areas with high agricultural phosphorus losses. Traditionally, the relative importance of point and diffuse sources has been assessed from annual P flux budgets, which are often dominated by diffuse inputs in storm runoff from intensively managed agricultural land. However, the ecological risk associated with nuisance algal growth in rivers is largely linked to soluble reactive phosphorus (SRP) concentrations during times of ecological sensitivity (spring/summer low-flow periods), when biological activity is at its highest. The relationships between SRP and total phosphorus (TP; total dissolved P + suspended particulate P) concentrations within UK rivers are evaluated in relation to flow and boron (B; a tracer of sewage effluent). SRP is the dominant P fraction (average 67% of TP) in all of the rivers monitored, with higher percentages at low flows. In most of the rivers the highest SRP concentrations occur under low-flow conditions and SRP concentrations are diluted as flows increase, which is indicative of point, rather than diffuse, sources. Strong positive correlations between SRP and B (also TP and B) across all the 54 river monitoring sites also confirm the primary importance of point source controls of phosphorus concentrations in these rivers, particularly during spring and summer low flows, which are times of greatest eutrophication risk. Particulate phosphorus (PP) may form a significant proportion of the phosphorus load to rivers, particularly during winter storm events, but this is of questionable relevance for river eutrophication

  5. Effect of phosphorus sources on phosphorus and nitrogen utilization by three sweet potato cultivars

    International Nuclear Information System (INIS)

    Montanez, A.; Zapata, F.; Kumarasinghe, K.S.

    1996-01-01

    A greenhouse experiment was conducted at the FAO/IAEA Agriculture and Biotechnology Laboratory in Seibersdorf, Austria using three sweet potato cultivars, TIS 2, TIS 3053 and TIS 1487. The three sweet potato cultivars were grown at two levels of phosphorus (0 kg P/kg soil and 60 kg P/kg soil). The fertilizer treatments consisted of two sources of phosphorus, Gafza rock Phosphate and triple super phosphate with 14.19 and 19.76% total phosphorus, respectively. 15 N labelled urea was used to study the nitrogen recovery in tubers from the applied nitrogen fertilizer. The results from these preliminary studies indicate that there is considerable genotypic variation among cultivars in the efficiency with which phosphorus and nitrogen are taken up and used to produce biomass. Their response to different sources of phosphorus are also variable. TIS-2 and TIS-1487 have a greater ability to absorb phosphorus from Gafza rock phosphate and produce higher tube yields indicating their greater potential for using alternative sources of natural phosphate fertilizers more effectively. Gafza rock phosphate also increased accumulation of nitrogen in TIS-1487, a characteristic which will place this cultivar at an advantage when growing in soils low in nitrogen. On an overall basis taking into account tuber yield, phosphorus use efficiency, and nitrogen use efficiency, TIS-2 may be considered the better candidate for introduction into soils poor in resources particularly phosphorus. This study was conducted with a limited number of cultivars due to limitation in the availability of germplasma. In spite of this, the differences in their abilities for phosphorus and nitrogen uptake and use are clearly visible which justifies large scale screening experiments using a broader germplasm base, in the future. (author). 14 refs, 1 fig., 3 tabs

  6. Effect of phosphorus sources on phosphorus and nitrogen utilization by three sweet potato cultivars

    Energy Technology Data Exchange (ETDEWEB)

    Montanez, A; Zapata, F [FAO/IAEA Agriculture and Biotechnology Lab., Seibersdorf (Austria). Soils Science Unit; Kumarasinghe, K S [Joint FAO/IAEA Div. of Nuclear Techniques in Food and Agriculture, Vienna (Austria). Soil Fertility, Irrigation and Crop Production Section

    1996-07-01

    A greenhouse experiment was conducted at the FAO/IAEA Agriculture and Biotechnology Laboratory in Seibersdorf, Austria using three sweet potato cultivars, TIS 2, TIS 3053 and TIS 1487. The three sweet potato cultivars were grown at two levels of phosphorus (0 kg P/kg soil and 60 kg P/kg soil). The fertilizer treatments consisted of two sources of phosphorus, Gafza rock Phosphate and triple super phosphate with 14.19 and 19.76% total phosphorus, respectively. {sup 15}N labelled urea was used to study the nitrogen recovery in tubers from the applied nitrogen fertilizer. The results from these preliminary studies indicate that there is considerable genotypic variation among cultivars in the efficiency with which phosphorus and nitrogen are taken up and used to produce biomass. Their response to different sources of phosphorus are also variable. TIS-2 and TIS-1487 have a greater ability to absorb phosphorus from Gafza rock phosphate and produce higher tube yields indicating their greater potential for using alternative sources of natural phosphate fertilizers more effectively. Gafza rock phosphate also increased accumulation of nitrogen in TIS-1487, a characteristic which will place this cultivar at an advantage when growing in soils low in nitrogen. On an overall basis taking into account tuber yield, phosphorus use efficiency, and nitrogen use efficiency, TIS-2 may be considered the better candidate for introduction into soils poor in resources particularly phosphorus. This study was conducted with a limited number of cultivars due to limitation in the availability of germplasma. In spite of this, the differences in their abilities for phosphorus and nitrogen uptake and use are clearly visible which justifies large scale screening experiments using a broader germplasm base, in the future. (author). 14 refs, 1 fig., 3 tabs.

  7. Interaction of arbuscular mycorrhizal symbionts with arsenic and other potentially toxic elements

    International Nuclear Information System (INIS)

    Khairuddin Abdul Rahim

    2000-01-01

    The response of arbuscular mycorrhizal (AM) symbionts to arsenic, and arsenic interactions with phosphorus and potentially toxic elements (PTEs) in soils from a former arsenic mine, the Devon Great Consols, were investigated. The objective was to determine whether AM associations ameliorate arsenic toxicity in Plantago lanceolata and Agrostis capillaris, plants commonly found at abandoned mines. An exploratory investigation indicated the richness in biodiversity of AMF that colonised plants growing at the site. Arsenic was found at high concentrations and was strongly associated with copper and iron. P. lanceolata was always colonised by AMF, while colonisation of A. capillaris was variable. There was no evidence in the field of soil pH or PTEs influencing AMF colonisation and spore density. There was no strong correlation between arsenic content in plant and available arsenic, obtained through various extraction methods. Spore germination and infectivity in the mine soils were strongly influenced by the AMF genotype and to a lesser extent by the soil environment. P. lanceolata and A. capillaris root growth was inhibited at arsenic concentrations of ≥50 μg g -1 in agar. Bioavailability experiments using mine soils and Terra-Green TM (calcined attapulgite) spiked with sodium arsenate gave no evidence that AMF-colonised plants translocated less arsenic to the shoots. Plants accumulated more arsenic in their roots than in their shoots, whether they were colonised by AMF or not. The A. capillaris genotype used in the present study translocated less of both arsenic and phosphorus to its shoots than P. lanceolata. High available phosphorus in Terra-Green TM protected plants against arsenic toxicity, at -1 As. There was evidence for inhibition by arsenic in AMF colonisation of roots. For quantifying AMF extra radical hyphae contribution to arsenic transportation from growth medium to plant using a compartmented pot system, the use of low phosphorus medium and a longer

  8. Method of making a cyanate ester foam

    Science.gov (United States)

    Celina, Mathias C.; Giron, Nicholas Henry

    2014-08-05

    A cyanate ester resin mixture with at least one cyanate ester resin, an isocyanate foaming resin, other co-curatives such as polyol or epoxy compounds, a surfactant, and a catalyst/water can react to form a foaming resin that can be cured at a temperature greater than 50.degree. C. to form a cyanate ester foam. The cyanate ester foam can be heated to a temperature greater than 400.degree. C. in a non-oxidative atmosphere to provide a carbonaceous char foam.

  9. SEQUENTIAL ELECTRODIALYTIC EXTRACTION OF PHOSPHORUS COMPOUNDS

    DEFF Research Database (Denmark)

    2017-01-01

    The present invention relates to an apparatus for electrodialytic extraction of phosphorus from a particulate material in suspension and to a method for electrodialytic phosphorus recovery, which uses the apparatus. The method may be applied for wastewater treatment, and/or treatment of particulate...... material rich in phosphorus. The present invention provides an apparatus for electrodialytic extraction of phosphorus from a particulate material comprising acidic and/or alkaline soluble phosphorus compounds, in suspension, comprising: • a first electrodialytic cell comprising a first anolyte compartment...

  10. Secondary toxicity in raptors caused by white phosphorus

    Science.gov (United States)

    Sparling, D.W.

    1995-01-01

    White phosphorus (WP) has caused waterfowl die-offs in a tidal saltmarsh used by the U.S. Army for artillery practice for > 40 years. Bald (Haliaeetus leucocephalus)and golden (Aquila chrysaetos) eagles have been observed feeding on dead and dying waterfowl on the marsh and may be exposed to WP through ingestion of contaminated birds. One carcass of each eagle species has been found with measurable levels of WP in fat. To determine if raptors can become intoxicated by ingesting prey that have been exposed to WP we fed live, 10-day-old white leghorn chicks three sublethal doses of WP. Six hrs after the last dose we euthanized the chicks and separated them into two groups--one with the digestive system from gizzard anteriorly removed (NoGut) and one with the digestive system intact and a 1.1 mg pellet of WP implanted deep into the crop (Pel). A third group of same-aged chicks unexposed to WP was used for controls. Fifteen kestrels (Fa/co sparverius) were randomly assigned to each of the treatments and 10 to the control diet. By 7 d of the study 8 of the kestrels had died on the Pel and 3 on the NoGut diet. Survivors on the Pel diet had significantly lower hematocrit, hemoglobin, final body weights and greater liver/body weight ratios and weight loss than control birds. The study showed that raptors and possibly other predators are at risk both when consuming flesh of prey that have succumbed to WP poisoning and when ingesting WP pellets that are incorporated in body parts but that the risk is greater when pellets are present.

  11. Secondary toxicity in raptors caused by white phosphorus

    Energy Technology Data Exchange (ETDEWEB)

    Sparling, D.W. [Patuxent Environmental Science Center, Laurel, MD (United States)

    1995-12-31

    White phosphorus (WP) has caused waterfowl die-offs in a tidal saltmarsh used by the US Army for artillery practice for > 40 years. Bald (Haliaeetus leucocephalus)and golden (Aquila chrysaetos) eagles have been observed feeding on dead and dying waterfowl on the marsh and may be exposed to WP through ingestion of contaminated birds. One carcass of each eagle species has been found with measurable levels of WP in fat. To determine if raptors can become intoxicated by ingesting prey that have been exposed to WP the authors fed live, 10-day-old white leghorn chicks three sublethal doses of WP. Six hrs after the last dose the authors euthanized the chicks and separated them into two groups one with the digestive system from gizzard anteriorly removed (NoGut) and one with the digestive system intact and a 1.1 mg pellet of WP implanted deep into the crop (Pel). A third group of same-aged chicks unexposed to WP was used for controls. Fifteen kestrels (Falco sparverius) were randomly assigned to each of the treatments and 1 0 to the control diet. By 7 d of the study 8 of the kestrels had died on the Pel and 3 on the NoGut diet. Survivors on the Pel diet had significantly lower hematocrit, hemoglobin, final body weights and greater liver/body weight ratios and weight loss than control birds. The study showed that raptors and possibly other predators are at risk both when consuming flesh of prey that have succumbed to WP poisoning and when ingesting WP pellets that are incorporated in body parts but that the risk is greater when pellets are present.

  12. Phosphorus containing sintered alloys (review)

    International Nuclear Information System (INIS)

    Muchnik, S.V.

    1984-01-01

    Phosphorus additives are considered for their effect on the properties of sintered alloys of different applications: structural, antifriction, friction, magnetic, hard, superhard, heavy etc. Data are presented on compositions and properties of phosphorus-containing materials produced by the powder metallurgy method. Phosphorus is shown to be an effective activator of sintering in some cases. When its concentration in the material is optimal it imparts the material such properties as strength, viscosity, hardness, wear resistance. Problems concerning powder metallurgy of amorphous phosphorus-containing alloys are reported

  13. Phosphorus and the dairy cow

    OpenAIRE

    Ekelund, Adrienne

    2003-01-01

    The general aim of the present work was to investigate phosphorus balance in the dairy cow, with reference to the amount and source of phosphorus. Furthermore, biochemical bone markers were used to study the bone turnover during the lactation and dry period. Phosphorus is located in every cell of the body and has more known functions than any other mineral element in the animal body. Phosphorus is also an important constituent of milk, and is therefore required in large amounts in a high yiel...

  14. Fertilizer phosphorus in some Finnish soils

    Directory of Open Access Journals (Sweden)

    Armi Kaila

    1961-01-01

    Full Text Available In the present paper it is tried to trace the fate of fertilizer phosphorus in soil by comparing the analyses of soils from treated and untreated plots of field trials. This indirect approach cannot be expected to provide exact values, but it is likely to give an approximate answer. The results reported above do not in any marked degree change our present conception of the forms in which fertilizer phosphorus accumulates in soils. In the acid soils studied (pH 4—6.4 in 0.02 N CaCl2 superphosphate tended to increase the fractions which were extracted by NH4F or NaOH. Hyperphosphate phosphorus was mostly found in the acid-soluble fraction. During a longer period of dressing with phosphate an increase in the organic phosphorus content of a peat soil could be detected. In the incubation experiments the mineralization of organic phosphorus occurred at a higher rate in the samples from the plots treated with superphosphate than in those from the untreated one. It might be supposed that the organic phosphorus mineralized mainly originated from the plant residues. It seems that the fractionation method developed by CHANG and JACKSON (4 for the estimation of discrete forms of soil phosphorus is not quite satisfactory for tracing the fertilizer phosphorus in soils recently dressed with phosphates. In particular, it may be fallacious to conclude that the fraction extracted by NH4F would only represent phosphorus bound to aluminium and its compounds. At least in the absence of soil, a large part of phosphorus in dicalcium phosphate dihydrate falls into this fraction, and also a small amount of hyperphosphate phosphorus may be found in it. The test values for »available» phosphorus showed the effect of fertilizers in accordance with previous observations (9, 13. Acetic acid soluble P revealed the treatment with hyperphosphate, but only slightly the application of superphosphate. The test value for the sorbed P of BRAY and KURTZ (2, or phosphorus

  15. Visualizing organophosphate precipitation at the calcite-water interface by in situ atomic force microscopy

    NARCIS (Netherlands)

    Wang, Lijun; Qin, Lihong; Putnis, Christine V.; Ruiz-Agudo, Encarnación; King, H.E.; Putnis, Andrew

    2016-01-01

    Esters of phosphoric acid constitute a large fraction of the total organic phosphorus (OP) in the soil environment and, thus, play an important role in the global phosphorus cycle. These esters, such as glucose-6-phosphate (G6P), exhibit unusual reactivity toward various mineral particles in soils,

  16. Comparative proteomic analysis of 2-MCPD- and 3-MCPD-induced heart toxicity in the rat.

    Science.gov (United States)

    Schultrich, Katharina; Frenzel, Falko; Oberemm, Axel; Buhrke, Thorsten; Braeuning, Albert; Lampen, Alfonso

    2017-09-01

    The chlorinated propanols 2- and 3-monochloropropanediol (MCPD), and their fatty acid esters have gained public attention due to their frequent occurrence as heat-induced food contaminants. Toxic properties of 3-MCPD in kidney and testis have extensively been characterized. Other 3-MCPD target organs include heart and liver, while 2-MCPD toxicity has been observed in striated muscle, heart, kidney, and liver. Inhibition of glycolysis appears to be important in 3-MCPD toxicity, whereas mechanisms of 2-MCPD toxicity are still unknown. It is thus not clear whether toxicity by the two isomeric compounds is dependent on similar or dissimilar modes of action. A 28-day oral feeding study in rats was conducted using daily non-toxic doses of 2-MCPD or 3-MCPD [10 mg/kg body weight], or an equimolar (53 mg/kg body weight) or a lower (13.3 mg/kg body weight) dose of 2-MCPD dipalmitate. Comprehensive comparative proteomic analyses of substance-induced alterations in the common target organ heart revealed striking similarities between effects induced by 2-MCPD and its dipalmitate ester, whereas the degree of effect overlap between 2-MCPD and 3-MCPD was much less. The present data demonstrate that even if exerting effects in the same organ and targeting similar metabolic networks, profound differences between molecular effects of 2-MCPD and 3-MCPD exist thus warranting the necessity of separate risk assessment for the two substances. This study for the first time provides molecular insight into molecular details of 2-MCPD toxicity. Furthermore, for the first time, molecular data on 3-MCPD toxicity in the heart are presented.

  17. Phosphorus Regulation in Chronic Kidney Disease.

    Science.gov (United States)

    Suki, Wadi N; Moore, Linda W

    2016-01-01

    Serum phosphorus levels stay relatively constant through the influence of multiple factors-such as parathyroid hormone, fibroblast growth factor 23, and vitamin D-on the kidney, bone, and digestive system. Whereas normal serum phosphorus ranges between 3 mg/dL to 4.5 mg/dL, large cross-sectional studies have shown that even people with normal kidney function are sometimes found to have levels ranging between 1.6 mg/dL and 6.2 mg/dL. While this may partially be due to diet and the factors mentioned above, total understanding of these atypical ranges of serum phosphorus remains uncertain. Risks for bone disease are high in people aged 50 and older, and this group comprises a large proportion of people who also have chronic kidney disease. Consuming diets low in calcium and high in phosphorus, especially foods with phosphate additives, further exacerbates bone turnover. Existing bone disease increases the risk for high serum phosphorus, and higher serum phosphorus has been associated with increased adverse events and cardiovascular-related mortality both in people with chronic kidney disease and in those with no evidence of disease. Once kidney function has deteriorated to end-stage disease (Stage 5), maintaining normal serum phosphorus requires dietary restrictions, phosphate-binding medications, and dialysis. Even so, normal serum phosphorus remains elusive in many patients with Stage 5 kidney disease, and researchers are testing novel targets that may inhibit intestinal transport of phosphorus to achieve better phosphate control. Protecting and monitoring bone health should also aid in controlling serum phosphorus as kidney disease advances.

  18. Allied, MGC link on cyanate esters

    International Nuclear Information System (INIS)

    Wood, A.

    1993-01-01

    In the latest of a line of joint ventures in its plastics business, Allied Signal has reached agreement with Mitsubishi Gas Chemical (MGC) to jointly develop thermoset cyanate ester resins and blends. The deal will involve further development of Allied Signal's Primaset phenol-formaldehyde cyanate ester resins, a new entrant in the thermoset arena. Although the Primaset resins were discovered in the 1960s, this would be the first time they are available commercially. The deal will marry Primaset technology with MGC's Skylex bisphenol A cyanate ester resins, says Fred DiAntonis, director/advanced materials at Allied Signal. The two firms are looking at marketing blends of the two materials. The potential market for these resins, used commercially by the electronics industry in printed circuit boards and by the aerospace industry in composites, is significant, says Robert P. Viarengo, Allied Signal president/performance materials. By aligning ourselves with MGC, the world leader in cyanate ester resin, we anticipate moving forward aggressively. The main competitor is Ciba, which acquired bisphenol A cyanate ester resins with its purchase of Rhone-Poulenc's high temperature resins business. DiAntonis estimates the market for cyanate ester resins could be worth $150 million by the end of the decade, although development costs have been in the tens of millions of dollars range

  19. Synthesis of a new energetic nitrate ester

    Energy Technology Data Exchange (ETDEWEB)

    Chavez, David E [Los Alamos National Laboratory

    2008-01-01

    Nitrate esters have been known as useful energetic materials since the discovery of nitroglycerin by Ascanio Sobrero in 1846. The development of methods to increase the safety and utility of nitroglycerin by Alfred Nobel led to the revolutionary improvement in the utility of nitroglycerin in explosive applications in the form of dynamite. Since then, many nitrate esters have been prepared and incorporated into military applications such as double-based propellants, detonators and as energetic plasticizers. Nitrate esters have also been shown to have vasodilatory effects in humans and thus have been studied and used for treatments of ailments such as angina. The mechanism of the biological response towards nitrate esters has been elucidated recently. Interestingly, many of the nitrate esters used for military purposes are liquids (ethylene glycol dinitrate, propylene glycol dinitrate, etc). Pentaerythritol tetranitrate (PETN) is one of the only solid nitrate esters, besides nitrocellulose, that is used in any application. Unfortunately, PETN melting point is above 100 {sup o}C, and thus must be pressed as a solid for detonator applications. A more practical material would be a melt-castable explosive, for potential simplification of manufacturing processes. Herein we describe the synthesis of a new energetic nitrate ester (1) that is a solid at ambient temperatures, has a melting point of 85-86 {sup o}C and has the highest density of any known nitrate ester composed only of carbon, hydrogen, nitrogen and oxygen. We also describe the chemical, thermal and sensitivity properties of 1 as well as some preliminary explosive performance data.

  20. Acute toxicity from baking soda ingestion.

    Science.gov (United States)

    Thomas, S H; Stone, C K

    1994-01-01

    Sodium bicarbonate is an extremely well-known agent that historically has been used for a variety of medical conditions. Despite the widespread use of oral bicarbonate, little documented toxicity has occurred, and the emergency medicine literature contains no reports of toxicity caused by the ingestion of baking soda. Risks of acute and chronic oral bicarbonate ingestion include metabolic alkalosis, hypernatremia, hypertension, gastric rupture, hyporeninemia, hypokalemia, hypochloremia, intravascular volume depletion, and urinary alkalinization. Abrupt cessation of chronic excessive bicarbonate ingestion may result in hyperkalemia, hypoaldosteronism, volume contraction, and disruption of calcium and phosphorus metabolism. The case of a patient with three hospital admissions in 4 months, all the result of excessive oral intake of bicarbonate for symptomatic relief of dyspepsia is reported. Evaluation and treatment of patients with acute bicarbonate ingestion is discussed.

  1. Can propolis and caffeic acid phenethyl ester (CAPE be promising agents against cyclophosphamide toxicity?

    Directory of Open Access Journals (Sweden)

    Sumeyya Akyol

    2016-03-01

    Full Text Available Propolis is a mixture having hundreds of polyphenols including caffeic acid phenethyl ester (CAPE. They have been using in several medical conditions/diseases in both in vitro and in vivo experimental setup. Cyclophosphamide has been used to treat a broad of malignancies including Hodgkin’s and non-Hodgking’s lymphoma, Burkitt’s lymphoma, chronic lymphocytic leukemia, Ewing’s sarcoma, breast cancer, testicular cancer, etc. It may cause several side effects after treatment. In this mini review, the protective effects of propolis and CAPE were compared each other in terms of effectiveness against cyclophosphamide-induced injuries. [J Complement Med Res 2016; 5(1.000: 105-107

  2. Phosphorus and Nutrition in Chronic Kidney Disease

    Directory of Open Access Journals (Sweden)

    Emilio González-Parra

    2012-01-01

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

  3. The location and nature of accumulated phosphorus in seven sludges from activated sludge plants which exhibited enhanced phosphorus removal

    International Nuclear Information System (INIS)

    Buchan, L.

    1981-01-01

    Electron microscopy combined with the energy dispersive analysis of X-rays (EDX) has been used to examine the nature of the phosphorus accumulated in sludges from seven activated sludge plants exhibiting enhanced phosphorus removal. Large phosphorus accumulations were located in identical structures in the sludges examined. The phosphorus was located in large electron-dense bodies, within large bacterial cells which were characteristically grouped in clusters. The calcium:phosphorus ratio of these electron-dense bodies precluded them from being any form of calcium phosphate precipitate. Quantitative analysis indicated that the electron-dense bodies contained in excess of 30% phosphorus. The results obtained are supportive of a biological mechanism of enhanced phosphorus uptake in activated sludge

  4. Heavy metal toxicity and iron chlorosis

    Energy Technology Data Exchange (ETDEWEB)

    DeKock, P C

    1956-01-01

    The toxicity of copper, nickel, cobalt, zinc, chromium, and manganese to mustard was studied in water culture, utilizing either the ionic form or the EDTA chelate of the metal in the presence of either ferric chloride or ferric EDTA. In presence of ferric chloride the activity of the metals in producing chlorosis was as given above, i.e. in the order of stability of their chelates. In the presence of ferric versenate, toxicity of the ionic metal was much reduced. The metal chelates gave very little indication of toxicity with either form of iron. It was found that the ratio of total phosphorus to total iron was higher in chlorotic plants than in green plants, irrespective of which metal was causing the toxicity. Copper could be demonstrated in the phloem cells of the root using biscyclohexanone-oxalydihydrazone as histochemical reagent. It is postulated that transport of iron probably takes place in the phloem as an active process. It would appear that as a major part of the iron in plant cells is attached to nucleo- or phospho-proteins, the heavy metals must be similarly attached to phospho-proteins.

  5. Fundamental Characterization of the Micellar Self-Assembly of Sophorolipid Esters.

    Science.gov (United States)

    Koh, Amanda; Todd, Katherine; Sherbourne, Ezekiel; Gross, Richard A

    2017-06-13

    Surfactants are ubiquitous constituents of commercial and biological systems that function based on complex structure-dependent interactions. Sophorolipid (SL) n-alkyl esters (SL-esters) comprise a group of modified naturally derived glycolipids from Candida bombicola. Herein, micellar self-assembly behavior as a function of SL-ester chain length was studied. Surface tensions as low as 31.2 mN/m and critical micelle concentrations (CMCs) as low as 1.1 μM were attained for diacetylated SL-decyl ester (dASL-DE) and SL-octyl ester, respectively. For deacetylated SL-esters, CMC values reach a lower limit at SL-ester chains above n-butyl (SL-BE, 1-3 μM). This behavior of SL-esters with increasing hydrophobic tail length is unlike other known surfactants. Diffusion-ordered spectroscopy (DOSY) and T 1 relaxation NMR experiments indicate this behavior is due to a change in intramolecular interactions, which impedes the self-assembly of SL-esters with chain lengths above SL-BE. This hypothesis is supported by micellar thermodynamics where a disruption in trends occurs at n-alkyl ester chain lengths above those of SL-BE and SL-hexyl ester (SL-HE). Diacetylated (dA) SL-esters exhibit an even more unusual trend in that CMC increases from 1.75 to 815 μM for SL-ester chain lengths of dASL-BE and dASL-DE, respectively. Foaming studies, performed to reveal the macroscopic implications of SL-ester micellar behavior, show that the observed instability in foams formed using SL-esters are due to coalescence, which highlights the importance of understanding intermicellar interactions. This work reveals that SL-esters are an important new family of green high-performing surfactants with unique structure-property relationships that can be tuned to optimize micellar characteristics.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-02-07

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

  7. Effect Of Wood-Based Biochar And Sewage Sludge Amendments For Soil Phosphorus Availability

    Directory of Open Access Journals (Sweden)

    Frišták Vladimír

    2015-06-01

    Full Text Available This study investigated the effects of two biochars (pyrolysed wood chips and garden clippings on phosphorus (P availability in a heavy-metal contaminated soil poor in phosphorus. Short-term 14-days incubation experiments were conducted to study how applications of biochars at different rates (1 and 5 % in combination with (1:1 and without dried sewage sludge from a municipal waste water treatment plant (WWTP affected the content of soil extractable P. For P-availability analyses deionized water, calcium acetate lactate (CAL, Mehlich 3 and Olsen extraction protocols were applied. In addition, the content of total and mobile forms of potentially toxic heavy metals (PTHM was studied. Application of both biochars caused a significant decrease of PTHM available forms in sewage sludge amended soil samples. The concentration of total and available P increased with higher biochar and sewage sludge application rates.

  8. Peak Phosphorus: Clarifying the Key Issues of a Vigorous Debate about Long-Term Phosphorus Security

    Directory of Open Access Journals (Sweden)

    Stuart White

    2011-10-01

    Full Text Available This paper reviews the latest information and perspectives on global phosphorus scarcity. Phosphorus is essential for food production and modern agriculture currently sources phosphorus fertilizers from finite phosphate rock. The 2008 food and phosphate fertilizer price spikes triggered increased concerns regarding the depletion timeline of phosphate rock reserves. While estimates range from 30 to 300 years and are shrouded by lack of publicly available data and substantial uncertainty, there is a general consensus that the quality and accessibility of remaining reserves are decreasing and costs will increase. This paper clarifies common sources of misunderstandings about phosphorus scarcity and identifies areas of consensus. It then asks, despite some persistent uncertainty, what would it take to achieve global phosphorus security? What would a ‘hard-landing’ response look like and how could preferred ‘soft-landing’ responses be achieved?

  9. Technetium and rhenium tracers with metabolizable ester functions

    International Nuclear Information System (INIS)

    Syhre, R.; Seifert, S.; Schneider, F.; Pietzsch, H.J.; Spies, H.; Johannsen, B.

    1993-01-01

    Re-DMSA (dimercaptosuccinic acid) ester complexes were prepored by ligand exchange reactions. To determine whether the ester band in Re-DMSA ester complexes is susceptible to cleavage by esterases, incubation experiments with tissue homogenates and plasma were carried out. (BBR)

  10. Phosphorus addition reverses the positive effect of zebra mussels (Dreissena polymorpha) on the toxic cyanobacterium, Microcystis aeruginosa.

    Science.gov (United States)

    Sarnelle, Orlando; White, Jeffrey D; Horst, Geoffrey P; Hamilton, Stephen K

    2012-07-01

    We tested the hypothesis that zebra mussels (Dreissena polymorpha) have positive effects on the toxin-producing cyanobacterium, Microcystis aeruginosa, at low phosphorus (P) concentrations, but negative effects on M. aeruginosa at high P, with a large-scale enclosure experiment in an oligotrophic lake. After three weeks, mussels had a significantly positive effect on M. aeruginosa at ambient P (total phosphorus, TP ∼10 μg L⁻¹), and a significantly negative effect at high P (simulating a TP of ∼40 μg L⁻¹ in lakes). Positive and negative effects were strong and very similar in magnitude. Thus, we were able to ameliorate a negative effect of Dreissena invasion on water quality (i.e., promotion of Microcystis) by adding P to water from an oligotrophic lake. Our results are congruent with many field observations of Microcystis response to Dreissena invasion across ecosystems of varying P availability. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. 21 CFR 172.854 - Polyglycerol esters of fatty acids.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Polyglycerol esters of fatty acids. 172.854 Section... HUMAN CONSUMPTION Multipurpose Additives § 172.854 Polyglycerol esters of fatty acids. Polyglycerol esters of fatty acids, up to and including the decaglycerol esters, may be safely used in food in...

  12. Stability of a metabolizable ester bond in radioimmunoconjugates

    International Nuclear Information System (INIS)

    Arano, Yasushi; Wakisaka, Kouji; Mukai, Takahiro; Uezono, Takashi; Motonari, Hiroshi; Akizawa, Hiromichi; Kairiyama, Claudia; Ohmomo, Yoshiro; Tanaka, Chiaki; Ishiyama, Munetaka; Sakahara, Harumi; Konishi, Junji; Yokoyama, Akira

    1996-01-01

    Ester bonds have been used as metabolizable linkages to reduce radioactivity levels in non-target tissues following the administration of antibodies labeled with metallic radionuclides. In this radiochemical design of antibodies, while the ester bonds should be cleaved rapidly in non-target tissues, high stability of the ester bonds in plasma is also required to preserve target radioactivity levels. To assess the structural requirements to stabilize the ester bond, a new benzyl-EDTA-derived bifunctional chelating agent with an ester bond, (1-[4-[4-(2-maleimidoethoxy)succinamido]benzyl]ethylenediamine-N,N,N',N'- tetraacetic acid; MESS-Bz-EDTA), was developed. MESS-Bz-EDTA was coupled with a thiolated monoclonal antibody (OST7, IgG 1 ) prepared by reducing its disulfide bonds to introduce the ester bond close and proximal to the antibody molecule. For comparison, 1-[4-(5-maleimidopentyl)aminobenzyl]ethylenediamine-N,N,N',N'-tetraacetic acid (EMCS-Bz-EDTA) and meleimidoethyl 3-[ 131 I]iodohippurate (MIH) was coupled to OST7 under the same conjunction chemistry. When incubated in 50% murine plasma or a buffered-solution of neutral pH, OST7-MESS-Bz-EDTA- 111 In rapidly released the radioactivity, and more than 95% of the initial radioactivity was liberated after a 24 h incubation in both solutions, due to a cleavage of the ester bond. On the other hand, only about 20% of the radioactivity was released from OST7-MIH- 131 I in both solutions during the same incubation period. In mice biodistribution studies, while a slightly faster radioactivity clearance from the blood with less radioactivity levels in the liver and kidneys was observed with OST7-MIH- 131 I than with OST7-EMCS-Bz-EDTA- 111 In, OST7-MESS-Bz-EDTA- 111 In indicated radioactivity clearance from the blood much faster than and almost comparable to that of OST7-MIH- 131 I and succinamidobenzyl-EDTA- 111 In, respectively. These findings as well as previous findings on radiolabeled antibodies with ester bonds

  13. Estimation of phosphorus flux in rivers during flooding.

    Science.gov (United States)

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

    2013-07-01

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

  14. Total phosphorus, phytate phosphorus contents and the correlation of phytates with amylose in selected edible beans in Sri Lanka

    Directory of Open Access Journals (Sweden)

    Keerthana Sivakumaran

    2018-02-01

    Full Text Available Phytate a major anti nutritional factors in legumes and it accounts for larger portion of the total phosphorus, while limiting the bioavailablity of certain divalent cations to the human body. Legumes of eleven varieties cultivated in Sri Lanka, Mung bean (MI5, MI6, Cowpea (Waruni, MICP1, Bombay, Dhawala, ANKCP1, Soybean (MISB1, Pb1 and Horse gram (ANKBlack, ANKBrown were analyzed for phosphorus content and phytate content. Total phosphorus content was quantified by dry ashing followed by spectrophotometrical measurement of the blue colour intensity of acid soluble phosphate with sodium molybdate in the presence of ascorbic acid while phytate phosphorus using anion exchange chromatographic technique followed by spectrometrical measurement of the digested organic phosphorus and amylose content by Simple Iodine-Colourimetric method. Where the least value for phosphorus was observed 275.04 ±1.44 mg.100g-1 in ANKBlack (Horse gram and the highest in MISB1 (Soyabean with 654.94 ±0.05 mg.100g-1. The phytate phosphorus content (which is a ratio of phyate to total phosphorus was highest in Dhawala (Cowpea. The phytate phosphorus (which is a ratio of phyate to total phosphorus was highest in Dhawala with 67.42% and least in Bombay (Cowpea with 24.87%. The amylose content of the legumes was least in Pb1 with 8.71 ±0.13 mg.100mg-1 and the highest in MI6 22.58 ±0.71 mg.100mg-1. The correlation between phyate and total phosphorus was significant (p <0.05 and positive (r = 0.62. Similarly the correlation coefficient for phytate phosphorus and total phosphorus was significant (p <0.05 and positive (r = 0.63. Amylose content of legumes was significantly correlated negatively (p <0.05 with the total phytates content (r = -0.82.

  15. Potential Phosphorus Mobilisation in Peat Soils

    DEFF Research Database (Denmark)

    Forsmann, Ditte M.; Kjærgaard, Charlotte

    2012-01-01

    Re-establishment of wetlands on peat soils containing phosphorus bound to iron(III)-oxides can lead to an undesirable phosphorus loss to the aquatic environment due to the reductive dissolution of iron(III)-oxides. Thus it is important to be able to assess the potential phosphorus mobilisation from...... peat soils before a re-establishment takes place. The potential phosphorus mobilisation from a peat soil depends not only on the geochemical characteristics but also on the redox conditions, the hydrological regime in the area as well as the hydro-physical properties of the soil. The hypothesis...... for this study is (i) the release of phosphorus in peat is controlled by the geochemistry; (ii) the mobilisation of phosphorus is controlled by both geochemistry and hydro-physics of the soil. For this study, 10 Danish riparian lowland areas with peat soil were selected based on their geochemical characteristics...

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

    OpenAIRE

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

    2011-01-01

    High phosphorus (P) loss from agricultural fields has been an environmental concern because of potential water quality problems in streams and lakes. To better understand the process of P loss and evaluate the effects of different phosphorus fertilization rates on phosphorus losses, the USDA Annualized AGricultural Non-Point Source (AnnAGNPS) pollutant loading model was applied to the Ohio Upper Auglaize watershed, located in the southern portion of the Maumee River Basin. In this study, the ...

  17. Estereótipos e mulheres na cultura marroquina

    OpenAIRE

    Sadiqi,Fatima

    2008-01-01

    Estereótipos sobre as mulheres no Marrocos podem ser caracterizados como crenças culturais incompletas e inexatas mantidas por algumas pessoas e que se encontram inscritos em expressões lingüísticas ou em discursos subliminares. A cultura popular marroquina emprega representações poderosas para transmitir e sustentar tais estereótipos. Embora existam alguns estereótipos positivos, a maioria dos estereótipos sobre as mulheres no Marrocos é negativa e reflete ditames patriarcais subliminares qu...

  18. Methyl esters from vegetable oils with hydroxy fatty acids: Comparison of lesquerella and castor methyl esters

    Science.gov (United States)

    The search for alternative feedstocks for biodiesel as partial replacement for petrodiesel has recently extended to castor oil. In this work, the castor oil methyl esters were prepared and their properties determined in comparison to the methyl esters of lesquerella oil, which in turn is seen as alt...

  19. Effect of mycorrhiza on growth criteria and phosphorus nutrition of lettuce (Lactuca sativa L. under different phosphorus application rates

    Directory of Open Access Journals (Sweden)

    S. Fatih Ergin

    2016-10-01

    Full Text Available In this study, effect of mycorrhiza on growth criteria and phosphorus nutrition of lettuce (Lactuca sativa L. under different phosphorus fertilization rates were investigated. Phosphorus were added into growing media as 0, 50, 100 and 200 mg P2O5/kg with and without mycorrhiza applications. Phosphorus applications significantly increased yield criteria of lettuce according to the control treatment statistically. Mycorrhiza application also significantly increased plant diameter, plant dry weight and phosphor uptake by plant. The highest phosphorus uptakes by plants were determined in 200 mg P2O5/kg treatments as 88.8 mg P/pot with mycorrhiza and 83.1 mg P/pot without mycorrhiza application. In the control at 0 doses of phosphorus with mycorrhiza treatment, phosphorus uptake (69.9 mg P/pot, edible weight (84.36 g, dry weight (8.64 g and leaf number (28 of lettuce were higher than that (47.7 mg P/pot, 59.33 g, 6.75 g and 20, respectively in the control without mycorrhiza application. It was determined that mycorrhiza had positive effect on growth criteria and phosphorus nutrition by lettuce plant, and this effect decreased at higher phosphorus application rates.

  20. Environmental Phosphorus Recovery Based on Molecular Bioscavengers

    DEFF Research Database (Denmark)

    Gruber, Mathias Felix

    Phosphorus is a ubiquitous element of all known life and as such it is found throughout numerous key molecules related to various cellular functions. The supply of phosphorus is tightly linked to global food security, since phosphorus is used to produce agricultural fertilizers, without which...... it would not be possible to feed the world population. Sadly, the current supply of phosphorus is based on the gradual depletion of limited fossil reserves, and some estimates predict that within 15-25 years we will consume more phosphorus than we can produce. There is therefore a strong international...... pressure to develop sustainable phosphorus practices as well as new technologies for phosphorus recovery. Nature has spent billions of years refining proteins that interact with phosphates. This has inspired the present work where the overall ambitions are: to facilitate the development of a recovery...

  1. Preparation of Spirocyclic β-Proline Esters

    DEFF Research Database (Denmark)

    Fjelbye, Kasper; Marigo, Mauro; Clausen, Rasmus Prætorius

    2017-01-01

    A series of novel N-Bn-protected spirocyclic β-proline esters were prepared using [3+2] cycloaddition and subsequently converted into their corresponding aldehydes. In addition, two novel N-Cbz-protected spirocyclic β-proline esters were prepared using intramolecular cyclization starting from...

  2. Electron spin resonance studies of γ-irradiated phosphite and phosphate esters. Identification of phosphinyl, phosphonyl, phosphoranyl, and phosphine dimer cation radicals

    International Nuclear Information System (INIS)

    Kerr, C.M.L.; Webster, K.; Williams, F.

    1975-01-01

    The powder ESR spectra of several γ-irradiated phosphorus esters at 77 0 K were analyzed into their distinguishable radical components, each spectrum being generally a composite of anisotropic features from a number of alkyl and phosphorus-centered radicals. Resolution of overlapping spectra was achieved in some instances by radiation-chemical experiments designed to suppress or enhance the products of electron capture relative to the radicals formed by other mechanisms. The radiation chemistry of dialkyl phosphites, (RO) 2 P(O)H, is influenced by the ease with which the P--H bond in these compounds is broken, the principal radicals being the phosphonyl species (RO) 2 PO and ROP(O)O - . Both of these species are thought to be the secondary products of hydrogen atom abstraction by the alkyl radical R which is produced by dissociative electron capture. A similar primary step was found to apply for the trialkyl phosphates, (RO) 3 PO, but in this case only carbon-centered radicals are formed by secondary H-atom abstraction processes. Results for the pyrophosphite differ from those for the trialkyl phosphites in showing the absence of alkyl radicals or their phosphoranyl adducts and the formation of the phosphonyl species (EtO) 2 PO, the latter being produced presumably by cleavage of the P--O--P bridge. The ESR parameters for each of the four main groups of phosphorus-centered radicals are summarized and the electronic structures of these radicals are discussed briefly

  3. Synthesis, Characterization and Biocompatibility of Biodegradable Elastomeric Poly(ether-ester urethane)s Based on Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) and Poly(ethylene glycol) via Melting Polymerization

    DEFF Research Database (Denmark)

    Li, Zibiao; Yang, Xiaodi; Wu, Linping

    2009-01-01

    Poly(ether-ester urethane)s (PUs) multiblock co-polymers were synthesized from telechelic hydroxylated poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) and poly(ethylene glycol) (PEG) via a melting polymerization (MP) process using 1,6-hexamethylene diisocyanate (HDI) as a non-toxic couplin...

  4. Synthesis of Estolide 2-ethylhexyl Ester from Ricinus communis

    International Nuclear Information System (INIS)

    Nazrizawati Ahmad Tajuddin; Nor Habibah Rosli

    2013-01-01

    Estolide 2-ethylhexyl ester synthesized through condensation reaction between ricinoleic acid from castor oil (Ricinus communis) and lauric acid, and then capped with 2-ethylhexyl alcohol. The reaction was continuously conducted under vacuum for 24 hours. Product of 2-ethylhexyl ester was characterized by using Fourier Transform Infrared (FTIR) to determine functional group and Nuclear Magnetic Resonans (NMR) for structure's determination. The presence of ester group at 1738.23 cm -1 wavenumber indicates that the formation of estolide ester has occurred. The vibration peak of C-O at 1174.60 cm -1 and 1117.10 cm -1 support the formation of ester. The presence of CH 2 bending indicated the long-chain compound. The ester methine signal at 3.8669 ppm indicated the estolide linkage in the 1 H-NMR spectrum while the 13 C-NMR showed two carbonyl signals at 173.41 ppm for acid and 173.56 ppm for ester. (author)

  5. Phthalate esters in marine algae

    OpenAIRE

    Gezgin, Tuncay; Güven, Kasim Cemal; Akçin, Göksel

    2001-01-01

    Abstract o-Phthalate esters as diethyl phthalate, dibutyl phthalate, di-isobutyl phthalate and diethylhexyl phthalate were identified at surface and inner part of algae collected in the Bosphorus, as Ulva lactuca, Enteromorpha linza, Cystoseria barbata, Pterocladia capillaceaeand Ceramium rubrum. The same esters were also detected in seawater samples taken from the same area. Thus parallelism in pollution was noted between the algae and the surrounding seawater,

  6. Effects of nitrogen and phosphorus on anatoxin-a, homoanatoxin-a, dihydroanatoxin-a and dihydrohomoanatoxin-a production by Phormidium autumnale.

    Science.gov (United States)

    Heath, Mark W; Wood, Susanna A; Barbieri, Rafael F; Young, Roger G; Ryan, Ken G

    2014-12-15

    Anatoxins are powerful neuromuscular blocking agents produced by some cyanobacteria. Consumption of anatoxin-producing cyanobacterial mats or the water containing them has been linked to numerous animal poisonings and fatalities worldwide. Despite this health risk, there is a poor understanding of the environmental factors regulating anatoxin production. Non-axenic Phormidium autumnale strain CAWBG557 produces anatoxin-a (ATX), homoanatoxin-a (HTX) and their dihydrogen-derivatives dihydroanatoxin-a (dhATX) and dihydrohomoanatoxin-a (dhHTX). The effects of varying nitrogen and phosphorus concentrations on the production of these four variants were examined in batch monocultures. The anatoxin quota (anatoxin per cell) of all four variants increased up to four fold in the initial growth phase (days 0-9) coinciding with the spread of filaments across the culture vessel during substrate attachment. Dihydroanatoxin-a and dhHTX, accounted for over 60% of the total anatoxin quota in each nitrogen and phosphorus treatment. This suggests they are being internally synthesised and not just derived following cell lysis and environmental degradation. The four anatoxin variants differed in their response to varying nitrogen and phosphorus concentrations. Notably, dhATX quota significantly decreased (P ≤ 0.03) when nitrogen and phosphorus concentrations were elevated (nitrogen = 21 mg L(-1); phosphorus = 3 mg L(-1)), while HTX quota increased when the phosphorus concentrations were reduced (ca. < 0.08 mg L(-1)). This is of concern as HTX has a high toxicity and anatoxin producing P. autumnale blooms in New Zealand usually occur in rivers with low water column dissolved reactive phosphorus. Copyright © 2014. Published by Elsevier Ltd.

  7. Traps for phosphorus adsorption

    International Nuclear Information System (INIS)

    Montoya, Nawer D; Villegas, Wilson E; Rodriguez, Lino M; Taborda, Nelson; Montes de C, Consuelo

    2001-01-01

    Several AL 2 O 3 supported oxides such as: NiO, CuO, Co 2 O 3 BaO, CeO 2 and ZnO were investigated for phosphorus adsorption. Zno/y-Al 2 O 3 exhibited the highest phosphorus adsorption capacity. However, since it diminishes the activity of to the reaction mixture it should be located upstream of the NoX catalyst, i.e. 0,3% Pd-H-MOR, in order to protect it against p poisoning. The treatment procedure with citric acid was effective for the removal of more than 70% phosphorus from the adsorbent, ZnO/y-Al 2 O 3

  8. Phosphorus recycling from an unexplored source by polyphosphate accumulating microalgae and cyanobacteria – a step to phosphorus security in agriculture

    Directory of Open Access Journals (Sweden)

    Chandan eMukherjee

    2015-12-01

    Full Text Available Phosphorus (P, an essential element required for crop growth has no substitute. The global food security depends on phosphorus availability in soil for crop production. World phosphorus reserves are fast depleting and with an annual increase of 2.3% in phosphorus demand, the current reserves will be exhausted in coming 50-100 years. India and other Western countries are forced to import phosphorus fertilizers at high costs to meet their agricultural demands due to uneven distribution of phosphate rocks on earth. The present study from India, aims to draw attention to an unnoticed source of phosphorus being wasted as parboiled rice mill effluent and subsequent bio-recovery of the valuable element from this unconventional source. The research was conducted in West Bengal, India, a state with the highest number of parboiled rice mills where its effluent carries on an average ~40 mg/L of soluble phosphorus. Technology to recover and recycle this wastewater P in India in a simple, inexpensive mode is yet to be optimized. Our strategy to use microalgae, Chlorella sp. and cyanobacteria, Cyanobacterium sp., Lyngbya sp. and Anabaena sp. to sequester the excess phosphorus from the effluent as polyphosphate inclusions and its subsequent recycling as slow and moderate release phosphorus biofertilizers to aid plant growth, preventing phosphorus loss and pollution, is a contemporary venture to meet the need of the hour. These polyphosphate accumulating microorganisms play a dual role of remediation and recovery of phosphorus, preliminarily validated in laboratory scale.

  9. Relative efficiency of different methods of phosphorus (32P) application on fertilizer phosphorus uptake by maize (zea may L.)

    International Nuclear Information System (INIS)

    Chaudhary, M.L.; Gupta, A.P.

    1975-01-01

    A green house study was conducted for comparing four methods of phosphorus application (broad cast, below the seed, one side and both sides of the seeds) at the rate of 60 ppm in sierozem soil of H issar (Haryana). Maize crop was planted in 50 cm. bottomless bitumin drums for 70 days i.e. upto tasseling stage. The plant samples were collected at jointing and tasseling stages of plant growth. The results revealed that the highest dry matter yield, total and fertilizer phosphorus uptake was observed when the phosphorus was applied below the seed, followed by both side application of phosphorus. The least yield, total and fertilizer phosphorus uptake were recorded when the phosphorus was broadcast at the time of sowing. (author)

  10. Evaluation and improvement of gamma-ray stability of chelating resins containing oxy-acid groups of phosphorus

    International Nuclear Information System (INIS)

    Jyo, Akinori; Yamabe, Kazunori; Shuto, Taketomi

    1998-01-01

    Chelating resins containing oxy-acid groups of phosphorus, such as phosphonic and phosphoric acid groups have been studied from the point of view of solvent extraction processes for the separation of nuclear fuel elements as well as of fission product ones. The present work was planned to evaluate the effect of gamma-ray on properties of the resins and to obtain directional information for design of the resins having high stability to gamma-ray. It was clarified that gamma-ray stability of the resins is not high; tolerance limit is ca. 2.3x10 3 C/kg. The present work also clarified that polymers crosslinked with divinylbenzene have much higher gamma-ray stability than ones crosslinked with dimetacrylate esters of oligo (ethylene glycol)s. (J.P.N.)

  11. Extraction and Liquid Chromatography-Tandem Mass Spectrometry Detection of 3-Monochloropropanediol Esters and Glycidyl Esters in Infant Formula.

    Science.gov (United States)

    Leigh, Jessica K; MacMahon, Shaun

    2016-12-14

    A method was developed for the extraction of fatty acid esters of 3-chloro-1,2-propanediol (3-MCPD) and glycidol from infant formula, followed by quantitative analysis of the extracts using liquid chromatography-tandem mass spectrometry (LC-MS/MS). These process-induced chemical contaminants are found in refined vegetable oils, and studies have shown that they are potentially carcinogenic and/or genotoxic, making their presence in edible oils (and processed foods containing these oils) a potential health risk. The extraction procedure involves a liquid-liquid extraction, where powdered infant formula is dissolved in water and extracted with ethyl acetate. Following shaking, centrifugation, and drying of the organic phase, the resulting fat extract is cleaned-up using solid-phase extraction and analyzed by LC-MS/MS. Method performance was confirmed by verifying the percent recovery of each 3-MCPD and glycidyl ester in a homemade powdered infant formula reference material. Average ester recoveries in the reference material ranged from 84.9 to 109.0% (0.6-9.5% RSD). The method was also validated by fortifying three varieties of commercial infant formulas with a 3-MCPD and glycidyl ester solution. Average recoveries of the esters across all concentrations and varieties of infant formula ranged from 88.7 to 107.5% (1.0-9.5% RSD). Based on the validation results, this method is suitable for producing 3-MCPD and glycidyl ester occurrence data in all commercially available varieties of infant formula.

  12. Contributions to total phosphorus intake: all sources considered.

    Science.gov (United States)

    Calvo, Mona S; Uribarri, Jaime

    2013-01-01

    High serum phosphorus is linked to poor health outcome and mortality in chronic kidney disease (CKD) patients before or after the initiation of dialysis. Dietary intake of phosphorus, a major determinant of serum phosphorus, seems to be systematically underestimated using the available software tools and generalized nutrient content databases. Several sources of dietary phosphorus including the addition of phosphorus ingredients in food processing, and phosphorus content of vitamin and mineral supplements and commonly used over-the-counter or prescription medications are not fully accounted for by the nutrient content databases and software programs in current clinical use or used in large population studies. In this review, we explore the many unknown sources of phosphorus in the food supply to identify all possible contributors to total phosphorus intake of Americans that have escaped inclusion in past intake estimates. Our goal is to help delineate areas for future interventions that will enable tighter control of dietary phosphorus intake, a critical factor to maintaining health and quality of life in CKD and dialysis patients. © 2012 Wiley Periodicals, Inc.

  13. Synthesis and Evaluation of the Antioxidant Activity of Lipophilic Phenethyl Trifluoroacetate Esters by In Vitro ABTS, DPPH and in Cell-Culture DCF Assays

    Directory of Open Access Journals (Sweden)

    Roberta Bernini

    2018-01-01

    Full Text Available Polyphenols are natural compounds showing a variety of health-promoting effects. Unfortunately, due to low lipid solubility, their applications in the pharmaceutical, food, and cosmetic industries are limited. With the aim of obtaining novel lipophilic derivatives, the present study reports the synthesis of a series of phenethyl trifluoroacetate esters containing up to two hydroxyl groups in the aromatic ring. Experimental logP values confirmed a greater lipophilicity of the novel compounds compared to the parent compounds. The radical scavenging capacity of all phenethyl trifluoroacetate esters was evaluated by in vitro assays (ABTS, DPPH and in cultured cells (L6 myoblasts and THP-1 leukemic monocytes using 2′,7′-dichlorodihydrofluorescein diacetate. These data revealed that the esters showed a good antioxidant effect that was strictly dependent on the grade of hydroxylation of the phenyl ring. The lack of toxicity, evaluated by the MTT assay and proliferation curves, makes these trifluoroacetates attractive derivatives for pharmaceutical, food, and cosmetic applications.

  14. Influence of integrated phosphorus supply and plant growth ...

    African Journals Online (AJOL)

    To guarantee a sufficient phosphorus supply for plants, a rapid and permanent mobilization of phosphorus from the labile phosphorus fractions is necessary, because phosphorus concentrations in soil solution are generally low. Several plant growth-promoting rhizobacteria (PGPR) have shown potential to enhance ...

  15. Gamma-aminobutyric acid esters. 1. Synthesis, brain uptake, and pharmacological studies of aliphatic and steroid esters of gamma-aminobutyric acid

    International Nuclear Information System (INIS)

    Shashoua, V.E.; Jacob, J.N.; Ridge, R.; Campbell, A.; Baldessarini, R.J.

    1984-01-01

    Labeled and unlabeled aliphatic and steroid esters of gamma-amino[U- 14 C]butyric acid (GABA) were synthesized and tested for their capacity to penetrate the blood-brain barrier and for evidence of central neuropharmacological activity in rodents. The uptake of the labeled 9,12,15-octadecatrienyl (linolenyl), 3-cholesteryl, 1-butyl, and the 9-fluoro-11 beta,17-dihydroxy-16 alpha-methyl-3,20-dioxopregna -1,4-dien-21-yl (dexamethasone) esters of GABA into mouse brain increased 2-, 25-, 74-, and 81-fold over GABA, respectively. The cholesteryl ester of GABA depressed the general motor activity of mice and rats in a dose-dependent manner, whereas the 1-butyl, linolenyl, and dexamethasone esters were inactive by this test. Studies of the rates of hydrolysis, GABA receptor binding capacity, and octanol/water partition coefficients indicated that pharmacological activity of the esters after entry into the central nervous system (CNS) was dependent on their capacity to release GABA by enzymatic hydrolysis and their lipid solubility

  16. Phosphorus determination by various substoichiometric methods

    International Nuclear Information System (INIS)

    Shigematsu, Toshio; Kudo, Kiyoshi

    1981-01-01

    Various substoichiometric methods have been classified from a view point of the substoichiometric separation. Based upon the substoichiometric separation, phosphorus was determined substoichiometrically by a direct method, a method of carrier amount variation and a comparison method for the irradiated sample. The direct method was applied to the determination of phosphorus in orchard leaves (SRM-1571). The analytical value was 0.23 +- 0.01%. Phosphorus in orchard leaves and spinach (SRM-1570) was determined by an ordinary method which devided the sample into equal parts in the method of carrier amount variation. Analytical values of orchard leaves and spinach were 0.22 +- 0.02% and 0.56 +- 0.04%, respectively. Moreover, a new modification of the method of carrier amount variation was studied by the use of various standard samples such as red phosphorus, spinach and orchard leaves. These standard samples were also employed for the determination of phosphorus in orchard leaves and 0.21 +- 0.01% was obtained. All these results are in good agreement with the value reported by NBS. The comparison method was applied to the determination of phosphorus in a semiconductor silicon single crystal. As a result of the correction of 32 P activity induced by the secondary nuclear reaction of 30 Si, 7.9 ppb and 3.1 ppb were obtained for the phosphorus concentrations in the single crystal silicon. (author)

  17. Effectiveness of bioremediation in reducing toxicity in oiled intertidal sediments

    International Nuclear Information System (INIS)

    Lee, K.; Tremblay, G.H.

    1995-01-01

    A 123-day field study was conducted with in situ enclosures to compare the effectiveness of bioremediation strategies based in inorganic and organic fertilizer additions to accelerate the biodegradation rates and reduce the toxicity of Venture trademark condensate stranded within sand-beach sediments. Comparison of the two fertilizer formulations with identical nitrogen and phosphorus concentrations showed that the organic fertilizer stimulated bacterial productivity within the oiled sediments to the greatest extent. However, detailed chemical analysis indicated that inorganic fertilizer additions were the most effective in enhancing condensate biodegradation rates. The Microtox reg-sign Solid-Phase Test (SPT) bioassay was determined to be sensitive to Venture Condensate in laboratory tests. Subsequent application of this procedure to oiled sediment in the field showed a reduction in sediment toxicity over time. However, the Microtox reg-sign bioassay procedure did not identify significant reductions in sediment toxicity following bioremediation treatment. An observed increase in toxicity following periodic additions of the organic fertilizer was attributed to rapid biodegradation rates of the fertilizer, which resulted in the production of toxic metabolic products

  18. Discrimination of processing grades of olive oil and other vegetable oils by monochloropropanediol esters and glycidyl esters

    NARCIS (Netherlands)

    Yan, Jing; Oey, Sergio B.; Leeuwen, van Stefan P.J.; Ruth, van Saskia M.

    2018-01-01

    In this study, the processing derived contaminants 2- and 3-monochloropropanediol (2- and 3-MCPD) esters and glycidyl esters (GEs) were analysed in 84 oil samples by GC–MS/MS for the discrimination of processing grades of olive oils as a potential authentication tool. Concentrations of 2- and 3-MCPD

  19. Visualizing alternative phosphorus scenarios for future food security

    Directory of Open Access Journals (Sweden)

    Tina-Simone Neset

    2016-10-01

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

  20. Visualizing Alternative Phosphorus Scenarios for Future Food Security.

    Science.gov (United States)

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

    2016-01-01

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

  1. Phosphorus K4 Crystal: A New Stable Allotrope

    OpenAIRE

    Jie Liu; Shunhong Zhang; Yaguang Guo; Qian Wang

    2016-01-01

    The intriguing properties of phosphorene motivate scientists to further explore the structures and properties of phosphorus materials. Here, we report a new allotrope named K 4 phosphorus composed of three-coordinated phosphorus atoms in non-layered structure which is not only dynamically and mechanically stable, but also possesses thermal stability comparable to that of the orthorhombic black phosphorus (A17). Due to its unique configuration, K 4 phosphorus exhibits exceptional properties: i...

  2. Effects of phorbol ester on mitogen-activated protein kinase kinase activity in wild-type and phorbol ester-resistant EL4 thymoma cells.

    Science.gov (United States)

    Gause, K C; Homma, M K; Licciardi, K A; Seger, R; Ahn, N G; Peterson, M J; Krebs, E G; Meier, K E

    1993-08-05

    Phorbol ester-sensitive and -resistant EL4 thymoma cell lines differ in their ability to activate mitogen-activated protein kinase (MAPK) in response to phorbol ester. Treatment of wild-type EL4 cells with phorbol ester results in the rapid activations of MAPK and pp90rsk kinase, a substrate for MAPK, while neither kinase is activated in response to phorbol ester in variant EL4 cells. This study examines the activation of MAPK kinase (MAPKK), an activator of MAPK, in wild-type and variant EL4 cells. Phosphorylation of a 40-kDa substrate, identified as MAPK, was observed following in vitro phosphorylation reactions using cytosolic extracts or Mono Q column fractions prepared from phorbol ester-treated wild-type EL4 cells. MAPKK activity coeluted with a portion of the inactive MAPK upon Mono Q anion-exchange chromatography, permitting detection of the MAPKK activity in fractions containing both kinases. This MAPKK activity was present in phorbol ester-treated wild-type cells, but not in phorbol ester-treated variant cells or in untreated wild-type or variant cells. The MAPKK from wild-type cells was able to activate MAPK prepared from either wild-type or variant cells. MAPKK activity could be stimulated in both wildtype and variant EL4 cells in response to treatment of cells with okadaic acid. These results indicate that the failure of variant EL4 cells to activate MAP kinase in response to phorbol ester is due to a failure to activate MAPKK. Therefore, the step that confers phorbol ester resistance to variant EL4 cells lies between the activation of protein kinase C and the activation of MAPKK.

  3. The phorbol ester fraction from Jatropha curcas seed oil: potential and limits for crop protection against insect pests.

    Science.gov (United States)

    Ratnadass, Alain; Wink, Michael

    2012-11-30

    The physic nut shrub, Jatropha curcas (Euphorbiaceae), has been considered as a "miracle tree", particularly as a source of alternate fuel. Various extracts of the plant have been reported to have insecticidal/acaricidal or molluscicidal/anthelminthic activities on vectors of medical or veterinary interest or on agricultural or non-agricultural pests. Among those extracts, the phorbol ester fraction from seed oil has been reported as a promising candidate for use as a plant-derived protectant of a variety of crops, from a range of pre-harvest and post-harvest insect pests. However, such extracts have not been widely used, despite the "boom" in the development of the crop in the tropics during recent years, and societal concerns about overuse of systemic chemical pesticides. There are many potential explanations to such a lack of use of Jatropha insecticidal extracts. On the one hand, the application of extracts potentially harmful to human health on stored food grain, might not be relevant. The problem of decomposition of phorbol esters and other compounds toxic to crop pests in the field needing further evaluation before such extracts can be widely used, may also be a partial explanation. High variability of phorbol ester content and hence of insecticidal activity among physic nut cultivars/ecotypes may be another. Phytotoxicity to crops may be further limitation. Apparent obstacles to a wider application of such extracts are the costs and problems involved with registration and legal approval. On the other hand, more studies should be conducted on molluscicidal activity on slugs and land snails which are major pests of crops, particularly in conservation agriculture systems. Further evaluation of toxicity to natural enemies of insect pests and studies on other beneficial insects such as pollinators are also needed.

  4. The Phorbol Ester Fraction from Jatropha curcas Seed Oil: Potential and Limits for Crop Protection against Insect Pests

    Science.gov (United States)

    Ratnadass, Alain; Wink, Michael

    2012-01-01

    The physic nut shrub, Jatropha curcas (Euphorbiaceae), has been considered as a “miracle tree”, particularly as a source of alternate fuel. Various extracts of the plant have been reported to have insecticidal/acaricidal or molluscicidal/anthelminthic activities on vectors of medical or veterinary interest or on agricultural or non-agricultural pests. Among those extracts, the phorbol ester fraction from seed oil has been reported as a promising candidate for use as a plant-derived protectant of a variety of crops, from a range of pre-harvest and post-harvest insect pests. However, such extracts have not been widely used, despite the “boom” in the development of the crop in the tropics during recent years, and societal concerns about overuse of systemic chemical pesticides. There are many potential explanations to such a lack of use of Jatropha insecticidal extracts. On the one hand, the application of extracts potentially harmful to human health on stored food grain, might not be relevant. The problem of decomposition of phorbol esters and other compounds toxic to crop pests in the field needing further evaluation before such extracts can be widely used, may also be a partial explanation. High variability of phorbol ester content and hence of insecticidal activity among physic nut cultivars/ecotypes may be another. Phytotoxicity to crops may be further limitation. Apparent obstacles to a wider application of such extracts are the costs and problems involved with registration and legal approval. On the other hand, more studies should be conducted on molluscicidal activity on slugs and land snails which are major pests of crops, particularly in conservation agriculture systems. Further evaluation of toxicity to natural enemies of insect pests and studies on other beneficial insects such as pollinators are also needed. PMID:23203190

  5. 21 CFR 172.852 - Glyceryl-lacto esters of fatty acids.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Glyceryl-lacto esters of fatty acids. 172.852... HUMAN CONSUMPTION Multipurpose Additives § 172.852 Glyceryl-lacto esters of fatty acids. Glyceryl-lacto esters of fatty acids (the lactic acid esters of mono- and diglycerides) may be safely used in food in...

  6. Thermal and mechanical properties of fatty acid starch esters.

    Science.gov (United States)

    Winkler, H; Vorwerg, W; Rihm, R

    2014-02-15

    The current study examined thermal and mechanical properties of fatty acid starch esters (FASEs). All highly soluble esters were obtained by the sustainable, homogeneous transesterification of fatty acid vinyl esters in dimethylsulfoxide (DMSO). Casted films of products with a degree of substitution (DS) of 1.40-1.73 were compared with highly substituted ones (DS 2.20-2.63). All films were free of any plasticizer additives. Hydrophobic surfaces were characterized by contact angle measurements. Dynamic scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA) revealed thermal transitions (T(g), T(m)) which were influenced by the internal plasticizing effect of the ester groups. Thermal gravimetric analysis (TGA) measurements showed the increased thermal stability toward native starch. Tensile tests revealed the decreasing strength and stiffness of the products with increasing ester-group chain length while the elongation increased up to the ester group laurate and after that decreased. Esters of the longest fatty acids, palmitate and stearate turned out to be brittle materials due to super molecular structures of the ester chains such as confirmed by X-ray. Summarized products with a DS 1.40-1.73 featured more "starch-like" properties with tensile strength up to outstanding 43 MPa, while products with a DS >2 behaved more "oil-like". Both classes of esters should be tested as a serious alternative to commercial starch blends and petrol-based plastics. The term Cnumber is attributed to the number of total C-Atoms of the fatty acid (e.g. C6=Hexanoate). Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. α-Imino Esters in Organic Synthesis: Recent Advances.

    Science.gov (United States)

    Eftekhari-Sis, Bagher; Zirak, Maryam

    2017-06-28

    α-Imino esters are useful precursors for the synthesis of a variety of types of natural and unnatural α-amino acid derivatives, with a wide range of biological activities. Due to the adjacent ester group, α-imino esters are more reactive relative to other types of imines and undergo different kinds of reactions, including organometallics addition, metal catalyzed vinylation and alkynylation, aza-Henry, aza-Morita-Baylis-Hillman, imino-ene, Mannich-type, and cycloaddition reactions, as well as hydrogenation and reduction. This review discusses the mechanism, scope, and applications of the reactions of α-imino esters and related compounds in organic synthesis, covering the literature from the last 12 years.

  8. Opposite effects of flurbiprofen and the nitroxybutyl ester of flurbiprofen on apoptosis in cultured guinea-pig gastric mucous cells

    OpenAIRE

    Johal, Kamaljit; Hanson, Peter J

    2000-01-01

    The nitric oxide (NO)-donating nitroxybutyl ester of flurbiprofen (NO-flurbiprofen), shows reduced gastro-intestinal toxicity relative to flurbiprofen. NO may exert either pro- or anti-apoptotic effects, while non-steroidal anti-inflammatory drugs may induce apoptosis. The aim of the present work was therefore to compare the effects of flurbiprofen and NO-flurbiprofen on apoptosis in guinea-pig gastric mucous cells.Apoptotic activity was assessed by assay of caspase activity and from the frag...

  9. Acute aquatic toxicity and biodegradation potential of biodiesel fuels

    International Nuclear Information System (INIS)

    Haws, R.A.; Zhang, X.; Marshall, E.A.; Reese, D.L.; Peterson, C.L.; Moeller, G.

    1995-01-01

    Recent studies on the biodegradation potential and aquatic toxicity of biodiesel fuels are reviewed. Biodegradation data were obtained using the shaker flask method observing the appearance of CO 2 and by observing the disappearance of test substance with gas chromatography. Additional BOD 5 and COD data were obtained. The results indicate the ready biodegradability of biodiesel fuels as well as the enhanced co-metabolic biodegradation of biodiesel and petroleum diesel fuel mixtures. The study examined reference diesel, neat soy oil, neat rape oil, and the methyl and ethyl esters of these vegetable oils as well as various fuel blends. Acute toxicity tests on biodiesel fuels and blends were performed using Oncorhynchus mykiss (Rainbow Trout) in a static non-renewal system and in a proportional dilution flow replacement system. The study is intended to develop data on the acute aquatic toxicity of biodiesel fuels and blends under US EPA Good Laboratory Practice Standards. The test procedure is designed from the guidelines outlined in Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms and the Fish Acute Aquatic Toxicity Test guideline used to develop aquatic toxicity data for substances subject to environmental effects test regulations under TSCA. The acute aquatic toxicity is estimated by an LC50, a lethal concentration effecting mortality in 50% of the test population

  10. Determination of phosphorus using derivative neutron activation

    International Nuclear Information System (INIS)

    Scindia, Y.M.; Nair, A.G.C.; Reddy, A.V.R.; Manohar, S.B.

    2002-01-01

    For the determination of phosphorus in different matrices, the derivative neutron activation analysis is especially applicable to aqueous samples, since the conventional neutron activation analysis is not useful for the determination of phosphorus. Phosphorus when reacted with ammonium molybdate 4 hydrate and ammonium metavanadate forms molybdo vanado phosphoric acid. This complex is preconcentrated by extracting into methyl isobutyl ketone. The organic phase containing the molybdo vanado phosphoric acid is neutron activated and the phosphorus is determined through the activation product of 52 V. Preparation of this complex, its stoichiometry, application to trace level determination of phosphorus and improved detection limit are discussed. This method was applied for the analysis of industrial effluent samples. (author)

  11. Origin of estradiol fatty acid esters in human ovarian follicular fluid.

    Science.gov (United States)

    Pahuja, S L; Kim, A H; Lee, G; Hochberg, R B

    1995-03-01

    The estradiol fatty acid esters are the most potent of the naturally occurring steroidal estrogens. These esters are present predominantly in fat, where they are sequestered until they are hydrolyzed by esterases. Thus they act as a preformed reservoir of estradiol. We have previously shown that ovarian follicular fluid from patients undergoing gonadotropin stimulation contains very high amounts of estradiol fatty acid esters (approximately 10(-7) M). The source of these esters is unknown. They can be formed by esterification of estradiol in the follicular fluid by lecithin:cholesterol acyltransferase (LCAT), or in the ovary by an acyl coenzyme A:acyltransferase. In order to determine which of these enzymatic processes is the source of the estradiol esters in the follicular fluid, we incubated [3H]estradiol with follicular fluid and cells isolated from human ovarian follicular fluid and characterized the fatty acid composition of the [3H]estradiol esters biosynthesized in each. In addition, we characterized the endogenous estradiol fatty acid esters in the follicular fluid and compared them to the biosynthetic esters. The fatty acid composition of the endogenous esters was different than those synthesized by the cellular acyl coenzyme A:acyltransferase, and the same as the esters synthesized by LCAT, demonstrating that the esters are produced in situ in the follicular fluid. Although the role of these estradiol esters in the ovary is not known, given their remarkable estrogenic potency it is highly probable that they have an important physiological role.

  12. Guiding phosphorus stewardship for multiple ecosystem services

    Science.gov (United States)

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

  13. Impacts of anthropic pressures on soil phosphorus availability, concentration, and phosphorus forms in sediments in a Southern Brazilian watershed

    Energy Technology Data Exchange (ETDEWEB)

    Pellegrini, Joao Batista Rossetto; Rheinheimer dos Santos, Danilo; Goncalves, Celso Santos; Copetti, Andre Carlos Cruz [Dept. de Solos, Univ. Federal de Santa Maria, Centro de Ciencias Rurais, Santa Maria, RS (Brazil); Bortoluzzi, Edson Campanhola [Faculdade de Agronomia e Medicina Veterinaria da Univ. de Passo Fundo, RS (Brazil); Tessier, Daniel [Inst. National de la Recherche Agronomique, Versailles (France)

    2010-04-15

    Purpose: The transfer of soil sediments and phosphorus from terrestrial to aquatic systems is a common process in agricultural lands. The aims of this paper are to quantify the soil phosphorus availability and to characterize phosphorus forms in soil sediments as contaminant agents of waters as a function of anthropic pressures. Materials and methods On three subwatersheds with different anthropic pressure, water and sediment samples were collected automatically in upstream and downstream discharge points in six rainfall events during the tobacco growing season. Phosphorus desorption capacity from soil sediments was estimated by successive extractions with anion exchange resins. First-order kinetic models were adjusted to desorption curves for estimating potentially bioavailable particulate phosphorus, desorption rate constant, and bioavailable particulate phosphorus. Results and discussion The amount of bioavailable particulate phosphorus was directly correlated with the iron oxide content. The value of desorption rate constant was directly related with the total organic carbon and inversely with the iron oxide contents. Phosphate ions were released to solution, on average, twice as rapidly from sediments collected in subwatersheds with low anthropic activity than from those ones of highly anthropic subwatersheds. Anthropic pressure on watershed can engender high sediment discharge, but these solid particles seem to present low phosphorus-releasing capacity to water during transport due to the evidenced high affinity between phosphorus and iron oxide from sediments. Conclusions Anthropic pressure was related with sediment concentration and phosphorus release to aquatic systems. While natural vegetation along streams plays a role on soil and water depuration, it is unable to eliminate the phosphorus inputs intrinsic to the agricultural-intensive systems. Recommendations and perspectives The contamination of water in watershed by phosphates is facilitated by the

  14. Investigation of bifunctional ester additives for methanol-gasoline system

    International Nuclear Information System (INIS)

    Zhang, J.; Yang, C.; Tang, Y.; Du, Q.; Song, N.; Zhang, Z.

    2014-01-01

    To explore new and multifunctional additives for methanol-gasoline, tartaric ester were synthesized and screened as phase stabilizer and saturation vapor pressure depressor for methanol-gasoline. The effect of the esters structure on the efficiency was discussed. The results show that the stabilities of the blends depend on the length of the glycolic esters alkoxy group. In addition, the tartaric esters also can depress the saturation vapor pressure of methanol-gasoline effectively in M15. Effect of the structure on the efficiency was also discussed. (author)

  15. Phosphorus-containing macrocyclic compounds: synthesis and properties

    International Nuclear Information System (INIS)

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

    2013-01-01

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

  16. Anthropogenic phosphorus flow analysis of Hefei City, China

    International Nuclear Information System (INIS)

    Li Sisi; Yuan Zengwei; Bi Jun; Wu Huijun

    2010-01-01

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

  17. Biological phosphorus uptake under anoxic and aerobic conditions

    DEFF Research Database (Denmark)

    Kerrn-Jespersen, Jens Peter; Henze, Mogens

    1993-01-01

    Biological phosphorus removal was investigated under anoxic and aerobic conditions. Tests were made to establish whether phosphorus accumulating bacteria can take up phosphate under anoxic conditions and thus utilise nitrate as oxidant. Furthermore, it was tested how the amount of organic matter...... as oxidant. The phosphorus uptake was more rapid under aerobic conditions than under anoxic conditions. The explanation of this is that all phosphorus accumulating bacteria take up phosphate under aerobic conditions, whereas only part of the phosphorus accumulating bacteria take up phosphate under anoxic...

  18. Molecular characterization and identification of markers for toxic and non-toxic varieties of Jatropha curcas L. using RAPD, AFLP and SSR markers.

    Science.gov (United States)

    Sudheer Pamidimarri, D V N; Singh, Sweta; Mastan, Shaik G; Patel, Jalpa; Reddy, Muppala P

    2009-07-01

    Jatropha curcas L., a multipurpose shrub has acquired significant economic importance for its seed oil which can be converted to biodiesel, is emerging as an alternative to petro-diesel. The deoiled seed cake remains after oil extraction is toxic and cannot be used as a feed despite having best nutritional contents. No quantitative and qualitative differences were observed between toxic and non-toxic varieties of J. curcas except for phorbol esters content. Development of molecular marker will enable to differentiate non-toxic from toxic variety in a mixed population and also help in improvement of the species through marker assisted breeding programs. The present investigation was undertaken to characterize the toxic and non-toxic varieties at molecular level and to develop PCR based molecular markers for distinguishing non-toxic from toxic or vice versa. The polymorphic markers were successfully identified specific to non-toxic and toxic variety using RAPD and AFLP techniques. Totally 371 RAPD, 1,442 AFLP markers were analyzed and 56 (15.09%) RAPD, 238 (16.49%) AFLP markers were found specific to either of the varieties. Genetic similarity between non-toxic and toxic verity was found to be 0.92 by RAPD and 0.90 by AFLP fingerprinting. In the present study out of 12 microsatellite markers analyzed, seven markers were found polymorphic. Among these seven, jcms21 showed homozygous allele in the toxic variety. The study demonstrated that both RAPD and AFLP techniques were equally competitive in identifying polymorphic markers and differentiating both the varieties of J. curcas. Polymorphism of SSR markers prevailed between the varieties of J. curcas. These RAPD and AFLP identified markers will help in selective cultivation of specific variety and along with SSRs these markers can be exploited for further improvement of the species through breeding and Marker Assisted Selection (MAS).

  19. Achieving Long-Term Protection of Water Quality of Grand Lake St. Marys Through Implementation of Conservation Practices and Control of Phosphorus Input from Agricultural Drainage

    Science.gov (United States)

    Grand Lake St. Marys (GLSM), a 13,000 acre lake in northwestern Ohio, is experiencing toxic levels of algal blooms resulting primarily from phosphorus input from agricultural runoff. The algal blooms are so severe that the Ohio Department of Natural Resources advised against any...

  20. Determination of the Mineral Composition and Toxic Element Contents of Propolis by Near Infrared Spectroscopy

    Directory of Open Access Journals (Sweden)

    M. Inmaculada González-Martín

    2015-11-01

    Full Text Available The potential of near infrared spectroscopy (NIR with remote reflectance fiber-optic probes for determining the mineral composition of propolis was evaluated. This technology allows direct measurements without prior sample treatment. Ninety one samples of propolis were collected in Chile (Bio-Bio region and Spain (Castilla-León and Galicia regions. The minerals measured were aluminum, calcium, iron, potassium, magnesium, phosphorus, and some potentially toxic trace elements such as zinc, chromium, nickel, copper and lead. The modified partial least squares (MPLS regression method was used to develop the NIR calibration model. The determination coefficient (R2 and root mean square error of prediction (RMSEP obtained for aluminum (0.79, 53, calcium (0.83, 94, iron (0.69, 134 potassium (0.95, 117, magnesium (0.70, 99, phosphorus (0.94, 24 zinc (0.87, 10 chromium (0.48, 0.6 nickel (0.52, 0.7 copper (0.64, 0.9 and lead (0.70, 2 in ppm. The results demonstrated that the capacity for prediction can be considered good for wide ranges of potassium, phosphorus and zinc concentrations, and acceptable for aluminum, calcium, magnesium, iron and lead. This indicated that the NIR method is comparable to chemical methods. The method is of interest in the rapid prediction of potentially toxic elements in propolis before consumption.

  1. Phosphorus kinetics in ovine fed with different phosphorus sources, using the isotopic dilution technique

    International Nuclear Information System (INIS)

    Vitti, D.M.S.S.; Abdalla, A.L.; Meirelles, C.F.

    1992-01-01

    Phosphorus kinetics in fluids and tissues of sheep was studied. Sixteen castrated sheep were kept in metabolism cages, receiving a semipuried diet containing as phosphorus sources dicalcium phosphate (BIC), monoammonium phosphate (MAP), superphosphate (SPT) and Tapita phosphate (TAP) 200 μCi P-32 was intravenously injected in each sheep and blood and feces were collected for eight days. From the specific activities in feces and plasma the endogenous phosphorus and the absorption coefficient were calculated. plasma P-32 half-life was determined. Nine days after injection the animals were killed and liver, kidney and muscle and bone samples were collected. P-32 retention and specific activities in tissues were determined. Endogenous phosphorus and absorption coefficient values were 54.44 ± 15.31 mh/kg live weight and 0.60; 47.98 ± 12.44 and 0.56; 39.70 ± 7.29 and 0.49; 59.11 ± 17.12 and 0.58 respectively bor BIC, MAP, TAP and SPT. P-32 retention by tissues was 0.29 ± 0.09; 0.27 ± 0.06; 0.16 ± 0.04 and 0.08 ± 0.03 dose/g fresh matter, respectively for bone, liver, kidney and muscle. It was concluded that animals which received TAP showed differences in absorption, distribution and P-32 retention by fluids and tissues. Phosphorus availability was lower for this source. (author)

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

    Science.gov (United States)

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

    2014-01-01

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

  3. Ester Tuiksoo - Eesti esimene naissoost põllumajandusminister / Ester Tuiksoo ; interv. Toomas Verrev

    Index Scriptorium Estoniae

    Tuiksoo, Ester, 1965-

    2007-01-01

    Ametist lahkuv põllumajandusminister Ester Tuiksoo räägib saadud juhtimiskogemusest, Euroopa Liidu ühise põllumajanduspoliitika juurutamisest, rahvuskala valimisest, Rahvaliidu käekäigust parlamendivalimistel

  4. 21 CFR 172.816 - Methyl glucoside-coconut oil ester.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Methyl glucoside-coconut oil ester. 172.816 Section... HUMAN CONSUMPTION Multipurpose Additives § 172.816 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut oil ester may be safely used in food in accordance with the following conditions: (a) It is the...

  5. Clinical and Pathological Findings on Intoxication by Yellow Phosphorus After Ingesting Firework Cracker: A Rare Case of Autopsy.

    Science.gov (United States)

    Türkmen Şamdanci, Emine; Çakir, Ebru; Şahin, Nurhan; Elmali, Candan; Sayin, Sadegül

    2016-01-01

    Yellow phosphorus is a toxic substance used in the production of firework cracker, fireworks, ammunition and agricultural dung. When ingested, it shows its effects mainly in the liver, the kidneys, and the brain. A four-year-old girl had died as a result of acute hepatic failure caused by ingesting a firework cracker. The case showed high levels of hepatic enzymes, along with non-specific signs such as nausea, vomiting and diarrhea. Autopsy revealed diffuse microvesicular steatosis in the liver and disseminated degeneration in the proximal tubules of the kidneys. In cases with concomitant hepatorenal failure and cardiovascular collapse, death is inevitable. However, when only hepatic failure develops, hepatic transplantation may be lifesaving. Although intoxication from ingesting yellow phosphorus has a very high rate of mortality, forensic cases are extremely rare in the literature.

  6. Phosphorus run-off assessment in a watershed.

    Science.gov (United States)

    Chebud, Yirgalem; Naja, Ghinwa M; Rivero, Rosanna

    2011-01-01

    The Watershed Assessment Model was used to simulate the runoff volume, peak flows, and non-point source phosphorus loadings from the 5870 km(2) Lake Okeechobee watershed as a case study. The results were compared to on-site monitoring to verify the accuracy of the method and to estimate the observed/simulated error. In 2008, the total simulated phosphorus contribution was 9634, 6524 and 3908 kg (P) y(-1) from sod farms, citrus farms and row crop farmlands, respectively. Although the dairies represent less than 1% of the total area of Kissimmee basin, the simulated P load from the dairies (9283 kg (P) y(-1) in 2008) made up 5.4% of the total P load during 2008. On average, the modeled P yield rates from dairies, sod farms and row crop farmlands are 3.85, 2.01 and 0.86 kg (P) ha(-1) y(-1), respectively. The maximum sediment simulated phosphorus yield rate is about 2 kg (P) ha(-1) and the particulate simulated phosphorus contribution from urban, improved pastures and dairies to the total phosphorus load was estimated at 9%, 3.5%, and 1%, respectively. Land parcels with P oversaturated soil as well as the land parcels with high phosphorus assimilation and high total phosphorus contribution were located. The most critical sub-basin was identified for eventual targeting by enforced agricultural best management practices. Phosphorus load, including stream assimilation, incoming to Lake Okeechobee from two selected dairies was also determined.

  7. Sustainable use of phosphorus: a finite resource.

    Science.gov (United States)

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

    2013-09-01

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

  8. EFSA CEF Panel (EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids), 2016. Scientific Opinion on Flavouring Group Evaluation 51, Revision 2 (FGE.51Rev2): Consideration of alicyclic ketones and secondary alcohols and related esters evaluated by the JECFA (59th meeting, ) structurally related to alicyclic ketones secondary alcohols and related esters in FGE.09Rev6 (2015b)

    DEFF Research Database (Denmark)

    Beltoft, Vibe Meister; Nørby, Karin Kristiane

    on metabolism and toxicity. The present consideration concerns a group of 24 alicyclic ketones and secondary alcohols and related esters evaluated by JECFA (59th meeting in 2002 and 63rd meeting in 2004). This revision is made due to inclusion of four additional substances cleared for genotoxicity concern...

  9. Towards a closed phosphorus cycle

    NARCIS (Netherlands)

    Keyzer, M.A.

    2010-01-01

    Summary: This paper stresses the need to address upcoming scarcity of phosphorus, a mineral nutrient that is essential for all life on Earth. Agricultural crops obtain phosphorus from the pool in the soil that can be replenished by recycling of organic material, or by application of inorganic

  10. 21 CFR 178.3600 - Methyl glucoside-coconut oil ester.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Methyl glucoside-coconut oil ester. 178.3600... SANITIZERS Certain Adjuvants and Production Aids § 178.3600 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut oil ester identified in § 172.816(a) of this chapter may be safely used as a processing...

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

    Science.gov (United States)

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

    2010-11-01

    The substance flow analysis (SFA) method was employed to examine phosphorus flow and its connection to water pollution in the city of Hefei, China, in 2008. As human activity is the driving force of phosphorus flux from the environment to the economy, the study provides a conceptual framework for analyzing an anthropogenic phosphorus cycle that includes four stages: extraction, fabrication and manufacturing, use, and waste management. Estimates of phosphorus flow were based on existing data as well as field research, expert advice, local accounting systems, and literature. The total phosphorus input into Hefei in 2008 reached 7810 tons, mainly as phosphate ore, chemical fertilizer, pesticides, crops and animal products. Approximately 33% of the total phosphorus input left the area, and nearly 20% of that amount was discharged as waste to surface water. Effluent containing excessive fertilizer from farming operations plays an important role in phosphorus overloads onto surface water; the other major emission source is sewage discharge. We also provide suggestions for reducing phosphorus emissions, for example reducing fertilizer use, recycling farming residues, and changing human consumption patterns. Crown Copyright © 2010. Published by Elsevier B.V. All rights reserved.

  12. ESTER: a new approach in modelling severe accidents

    International Nuclear Information System (INIS)

    Shepherd, I.; Jones, A.; Schmidt, F.

    1993-01-01

    ESTER is a set of codes for calculating phenomena during severe accidents in thermal reactors. It makes use of software tools that allow the data to be defined as a tree-structured data base and this data to be stored and retrieved by the code modules. The tools include generalized input and output routines that are independent of the particular code being used. Severe accident research codes are in a continual state of development and the structure of ESTER is such that modifications can be introduced easily and safely. The ESTER framework also facilitates the coupling together of codes. A preliminary version of ESTER containing a complete set of tools and a limited number of applications has already been released. 9 refs., 5 figs

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

    Science.gov (United States)

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

    2015-12-01

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

  14. [Research progress on phosphorus budgets and regulations in reservoirs].

    Science.gov (United States)

    Shen, Xiao; Li, Xu; Zhang, Wang-shou

    2014-12-01

    Phosphorus is an important limiting factor of water eutrophication. A clear understanding of its budget and regulated method is fundamental for reservoir ecological health. In order to pro- mote systematic research further and improve phosphorus regulation system, the budget balance of reservoir phosphorus and its influencing factors were concluded, as well as conventional regulation and control measures. In general, the main phosphorus sources of reservoirs include upstream input, overland runoff, industrial and domestic wastewater, aquaculture, atmospheric deposition and sediment release. Upstream input is the largest phosphorus source among them. The principal output path of phosphorus is the flood discharge, the emission load of which is mainly influenced by drainage patterns. In addition, biological harvest also can export a fraction of phosphorus. There are some factors affecting the reservoir phosphorus balance, including reservoirs' function, hydrological conditions, physical and chemical properties of water, etc. Therefore, the phosphorus budgets of different reservoirs vary greatly, according to different seasons and regions. In order to reduce the phosphorus loading in reservoirs, some methods are carried out, including constructed wetlands, prefix reservoir, sediment dredging, biomanipulation, etc. Different methods need to be chosen and combined according to different reservoirs' characteristics and water quality management goals. Thus, in the future research, it is reasonable to highlight reservoir ecological characteristics and proceed to a complete and systematic analysis of the inherent complexity of phosphorus budget and its impact factors for the reservoirs' management. Besides, the interaction between phosphorus budget and other nutrients in reservoirs also needs to be conducted. It is fundamental to reduce the reservoirs' phosphorus loading to establish a scientific and improved management system based on those researches.

  15. The New Nordic Diet: phosphorus content and absorption.

    Science.gov (United States)

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

    2016-04-01

    High phosphorus content in the diet may have adverse effect on cardiovascular health. We investigated whether the New Nordic Diet (NND), based mainly on local, organic and less processed food and large amounts of fruit, vegetables, wholegrain and fish, versus an Average Danish Diet (ADD) would reduce the phosphorus load due to less phosphorus-containing food additives, animal protein and more plant-based proteins. Phosphorus and creatinine were measured in plasma and urine at baseline, week 12 and week 26 in 132 centrally obese subjects with normal renal function as part of a post hoc analysis of data acquired from a 26-week controlled trial. We used the fractional phosphorus excretion as a measurement of phosphorus absorption. Mean baseline fractional phosphorus excretion was 20.9 ± 6.6 % in the NND group (n = 82) and 20.8 ± 5.5 % in the ADD group (n = 50) and was decreased by 2.8 ± 5.1 and 3.1 ± 5.4 %, respectively, (p = 0.6) at week 26. At week 26, the mean change in plasma phosphorus was 0.04 ± 0.12 mmol/L in the NND group and -0.03 ± 0.13 mmol/L in the ADD group (p = 0.001). Mean baseline phosphorus intake was 1950 ± 16 mg/10 MJ in the NND group and 1968 ± 22 mg/10 MJ in the ADD group and decreased less in the NND compared to the ADD (67 ± 36 mg/10 MJ and -266 ± 45 mg/day, respectively, p food concept beneficial regarding phosphorus absorption.

  16. 21 CFR 172.848 - Lactylic esters of fatty acids.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Lactylic esters of fatty acids. 172.848 Section 172... CONSUMPTION Multipurpose Additives § 172.848 Lactylic esters of fatty acids. Lactylic esters of fatty acids... prepared from lactic acid and fatty acids meeting the requirements of § 172.860(b) and/or oleic acid...

  17. Adaptive Evolution of Phosphorus Metabolism in Prochlorococcus

    DEFF Research Database (Denmark)

    Casey, John R; Mardinoglu, Adil; Nielsen, Jens

    2016-01-01

    Inorganic phosphorus is scarce in the eastern Mediterranean Sea, where the high-light-adapted ecotype HLI of the marine picocyanobacterium Prochlorococcus marinus thrives. Physiological and regulatory control of phosphorus acquisition and partitioning has been observed in HLI both in culture...... and in the field; however, the optimization of phosphorus metabolism and associated gains for its phosphorus-limited-growth (PLG) phenotype have not been studied. Here, we reconstructed a genome-scale metabolic network of the HLI axenic strain MED4 (iJC568), consisting of 568 metabolic genes in relation to 794...... through drastic depletion of phosphorus-containing biomass components but also through network-wide reductions in phosphate-reaction participation and the loss of a key enzyme, succinate dehydrogenase. These alterations occur despite the stringency of having relatively few pathway redundancies...

  18. Phosphorus effect on fracture properties of structural steels

    International Nuclear Information System (INIS)

    Goritskij, V.M.; Guseva, I.A.

    1985-01-01

    Phosphorus content is studied for its effect on fracture peculiarities and fracture toughness. It is supposed that the phosphorus effect on ductile fractures is associated with phosphorus segregation on the ferrite-carbide interfaces. An increase of the phosphorus content in heat-treated 10KhSND steel from 0.020 up to 0.043 wt.% results in a decrease of the pore size and asub(p) value. Close linear correlation is established between critical temperature of embrittlement T 50 and √ asub(p) or √ KC values for a number of structural steels with different phosphorus content

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

    Science.gov (United States)

    Slootweg, J Chris

    2018-05-07

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

  20. An Improved Enzymatic Indirect Method for Simultaneous Determinations of 3-MCPD Esters and Glycidyl Esters in Fish Oils.

    Science.gov (United States)

    Miyazaki, Kinuko; Koyama, Kazuo

    2017-10-01

    The enzymatic indirect method for simultaneous determinations of 3-chloro-1, 2-propanediol fatty acid esters (3-MCPD-Es) and glycidyl fatty acid esters (Gly-Es) make use of lipase from Candida cylindracea (previously referred to as C. rugosa). Because of low substrate specificity of the lipase for esters of polyunsaturated fatty acids (PUFA), such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), fish oils high in PUFAs are currently excluded from the range of application of the method. The objective of this study was to make the enzymatic indirect method applicable to fats and oils containing PUFAs. By using a Burkholderia cepacia lipase, and by removing sodium bromide from hydrolysis step and adding it after completion of the hydrolysis step, satisfactory recovery rates of 91-109% for 3-MCPD, and 91-110% for glycidol (Gly) were obtained from an EPA and DHA concentrated sardine oil, three DHA concentrated tuna oils, two fish oils, and five fish-oil based dietary supplements spiked with DHA-esters or oleic acid-esters of 3-MCPD and Gly at 20 mg/kg. Further, results from unspiked samples of seven fish oil based dietary supplements and five DHA concentrated tuna oils analyzed by the improved enzymatic indirect method were compared with the results analyzed by AOCS Cd 29a. For all 3-MCPD, 2-MCPD and Gly, the 95% confidence intervals determined by the weighted Deming regression for slopes and intercepts contained the value of 1 and 0, respectively. It was therefore concluded that the results from the two methods were not statistically different. These results suggest that fish oils high in PUFAs may be included in the range of application for the improved enzymatic indirect method for simultaneous determinations of 3-MCPD and Gly esters in fats and oils.

  1. Toughened cyanate ester alloys via reaction-induced phase separation; Hanno yuhatsugataso bunkai ni yoru taishogekisei cyanate ester alloy

    Energy Technology Data Exchange (ETDEWEB)

    Hirohata, T.; Kuroda, M.; Nishimura, A. [Sumitomo Electric Industries, Ltd., Osaka (Japan); Inoue, T. [Tokyo Institute of Technology, Tokyo (Japan)

    1998-03-15

    For the purpose of toughening the matrices of fiber-reinforced plastics (FRPs), the effect of thermosetting/thermoplastic polymer alloys based on cyanate ester alloys is investigated. In the experiment, materials are heated and then allowed to set, which are mixtures of 87.0-43.5wt% of cyanate ester resin, 0-43.5wt% of epoxy resin, and 13.0wt% of soluble polyimide. FRP properties are examined by measuring the after-shock compressive strength, flexural elasticity and flaxural strength, and by performing morphology observation. It is then found that a cyanate ester/soluble polyimide system forms a polymer alloy with phase separation, that its glass transition temperature does not drop, and that the rupture strength is increased approximately twice. A carbon fiber-reinforced plastic (CFRP) incorporating this system is twice higher in after-shock compression strength than a CFRP incorporating a cyanate ester. The system withstands high temperatures, retaining at 200degC approximately 90% of the elastic modulus it exhibits at room temperature. 15 refs., 16 figs.

  2. Electric Conductivity of Phosphorus Nanowires

    International Nuclear Information System (INIS)

    Jing-Xiang, Zhang; Hui, Li; Xue-Qing, Zhang; Kim-Meow, Liew

    2009-01-01

    We present the structures and electrical transport properties of nanowires made from different strands of phosphorus chains encapsulated in carbon nanotubes. Optimized by density function theory, our results indicate that the conductance spectra reveal an oscillation dependence on the size of wires. It can be seen from the density of states and current-voltage curves that the structure of nanowires affects their properties greatly. Among them, the DNA-like double-helical phosphorus nanowire exhibits the distinct characteristic of an approximately linear I – V relationship and has a higher conductance than others. The transport properties of phosphorus nanowires are highly correlated with their microstructures. (condensed matter: structure, mechanical and thermal properties)

  3. Activities of Jatropha curcas phorbol esters in various bioassays.

    Science.gov (United States)

    Devappa, Rakshit K; Rajesh, Sanjay K; Kumar, Vikas; Makkar, Harinder P S; Becker, Klaus

    2012-04-01

    Jatropha curcas seeds contain 30-35% oil, which can be converted to high quality biodiesel. However, Jatropha oil is toxic, ascribed to the presence of phorbol esters (PEs). In this study, isolated phorbol ester rich fraction (PEEF) was used to evaluate the activity of PEs using three aquatic species based bioassays (snail (Physa fontinalis), brine shrimp (Artemeia salina), daphnia (Daphnia magna)) and microorganisms. In all the bioassays tested, increase in concentration of PEs increased mortality with an EC(50) (48 h) of 0.33, 26.48 and 0.95 mg L(-1) PEs for snail, artemia and daphnia, respectively. The sensitivity of various microorganisms for PEs was also tested. Among the bacterial species tested, Streptococcus pyogenes and Proteus mirabilis were highly susceptible with a minimum inhibitory concentration (MIC) of 215 mg L(-1) PEs; and Pseudomonas putida were also sensitive with MIC of 251 mg L(-1) PEs. Similarly, Fusarium species of fungi exhibited EC(50) of 58 mg L(-1) PEs, while Aspergillus niger and Curvularia lunata had EC(50) of 70 mg L(-1). The snail bioassay was most sensitive with 100% snail mortality at 1 μg of PEs mL(-1). In conclusion, snail bioassay could be used to monitor PEs in Jatropha derived products such as oil, biodiesel, fatty acid distillate, kernel meal, cake, glycerol or for contamination in soil or other environmental matrices. In addition, PEs with molluscicidal/antimicrobial activities could be utilized for agricultural and pharmaceutical applications. Copyright © 2011 Elsevier Inc. All rights reserved.

  4. Spectroscopic studies of the quality of WCO (Waste Cooking Oil fatty acid methyl esters

    Directory of Open Access Journals (Sweden)

    Matwijczuk Arkadiusz

    2018-01-01

    Full Text Available Different kinds of biodiesel fuels become more and more attractive form of fuel due to their unique characteristics such as: biodegradability, replenishability, and what is more a very low level of toxicity in terms of using them as a fuel. The test on the quality of diesel fuel is becoming a very important issue mainly due to the fact that its high quality may play an important role in the process of commercialization and admitting it on the market. The most popular techniques among the wellknown are: molecular spectroscopy and molecular chromatography (especially the spectroscopy of the electron absorption and primarily the infrared spectroscopy (FTIR.The issue presents a part of the results obtained with the use of spectroscopy of the electron absorption and in majority infrared spectroscopy FTIR selected for testing samples of the acid fats WCO (Waste Cooking Oil types. The samples were obtained using laboratory methods from sunflower oil and additionally from waste animal fats delivered from slaughterhouses. Acid methyl esters were selected as references to present the samples. In order to facilitate the spectroscopic analysis, free glycerol, methanol, esters and methyl linolenic acid were measured

  5. Production of carrier-free phosphorus-33 at MURR

    International Nuclear Information System (INIS)

    Jia, W.; Ketring, A.R.; Schuh, J.; Lanigan, J.; Ma, D.; Manson, L.; Chanley, D.

    1996-01-01

    Phosphorus-33, a new radionuclide used in medical and biochemical research, is produced at the University of Missouri research reactor (MURR) in production quantities. Phosphorus-33 has a longer shelf life and lower dose rates than phosphorus-32. Recently, the MURR and New England Nuclear (NEN) jointly developed a method to recover carrier-free phosphorus-33 as well as the enriched sulfur target using a sublimation technique at reduced pressure

  6. Segmented poly(ether ester)s and poly(ether ester amide)s for use in tissue engineering

    OpenAIRE

    Deschamps, A.A.

    2002-01-01

    The objective of the studies described in this thesis is to investigate the applicability of these slowly degradable thermoplastic elastomers as scaffolds for tissue engineering, with emphasis on their phase separation and degradation properties. A second thermoplastic elastomer in which the terephthalic moieties have been replaced by ester-amide segments, is also investigated for use in scaffolding.

  7. Prevalence of phosphorus containing food additives in grocery stores

    Directory of Open Access Journals (Sweden)

    Janeen B. Leon

    2012-06-01

    In conclusion, phosphorus additives are commonly present in groceries and contribute significantly to the phosphorus content of foods. Moreover, phosphorus additive foods are less costly than additive-free foods. As a result, phosphorus additives may be an important contributor to hyperphosphatemia among persons with chronic kidney disease

  8. The Adequacy of Phosphorus Binder Prescriptions Among American Hemodialysis Patients

    Science.gov (United States)

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

    2013-01-01

    Because hemodialysis treatment has a limited ability to remove phosphorus, dialysis patients must restrict dietary phosphorus intake and use phosphorus binding medication. Among patients with restricted dietary phosphorus intake (1000 mg/d), phosphorus binders must bind about 250 mg of excess phosphorus per day and among patients with more typical phosphorus intake (1500 mg/d), binders must bind about 750 mg per day. To determine the phosphorus binding capacity of binder prescriptions among American hemodialysis patients, we undertook a cross-sectional study of a random sample of in-center chronic hemodialysis patients. We obtained data for one randomly selected patient from 244 facilities nationwide. About one-third of patients had hyperphosphatemia (serum phosphorus level > 5.5 mg/dL). Among the 224 patients prescribed binders, the mean phosphorus binding capacity was 256 mg/d (SD 143). 59% of prescriptions had insufficient binding capacity for restricted dietary phosphorus intake, and 100% had insufficient binding capacity for typical dietary phosphorus intake. Patients using two binders had a higher binding capacity than patients using one binder (451 vs. 236 mg/d, p phosphorus balance. Use of two binders results in higher binder capacity. Further work is needed to understand the impact of binder prescriptions on mineral balance and metabolism and to determine the value of substantially increasing binder prescriptions. PMID:23013171

  9. Preliminary analysis of phosphorus flow in Hue Citadel.

    Science.gov (United States)

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

    2016-01-01

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

  10. Isotopic techniques to study phosphorus cycling in soils

    International Nuclear Information System (INIS)

    Manjaiah, K.M.; Sreenivasa Chari, M.; Sachdev, P.; Sachdev, M.S.

    2008-01-01

    A sound understanding of phosphorus cycling in soil system is essential in order to manage this system in a sustainable manner. Phosphorus transformations are characterized by physico-chemical (sorption-desorption) and biological processes . The transformation rates need to be taken into account while developing nutrient management strategies for economical and sustainable production. One of the important tools and the method gaining popularity for determining the gross transformation rates of nutrients in the soil is the isotopic dilution technique. The major processes in the soil-plant system which determine the distribution and bioavailability of phosphorus in various inorganic and organic soil components consist of: (1) the dissolution of soil mineral phosphates, (2) retention of phosphorus by inorganic soil constituents, (3) decomposition of organic phosphorus contained in plant, animal and microbial detritus and (4) Immobilization of phosphorus via the soil microbial biomass and plan uptake

  11. Potential Grape-Derived Contributions to Volatile Ester Concentrations in Wine

    Directory of Open Access Journals (Sweden)

    Paul K. Boss

    2015-04-01

    Full Text Available Grape composition affects wine flavour and aroma not only through varietal compounds, but also by influencing the production of volatile compounds by yeast. C9 and C12 compounds that potentially influence ethyl ester synthesis during fermentation were studied using a model grape juice medium. It was shown that the addition of free fatty acids, their methyl esters or acyl-carnitine and acyl-amino acid conjugates can increase ethyl ester production in fermentations. The stimulation of ethyl ester production above that of the control was apparent when lower concentrations of the C9 compounds were added to the model musts compared to the C12 compounds. Four amino acids, which are involved in CoA biosynthesis, were also added to model grape juice medium in the absence of pantothenate to test their ability to influence ethyl and acetate ester production. β-Alanine was the only one shown to increase the production of ethyl esters, free fatty acids and acetate esters. The addition of 1 mg∙L−1 β-alanine was enough to stimulate production of these compounds and addition of up to 100 mg∙L−1 β-alanine had no greater effect. The endogenous concentrations of β-alanine in fifty Cabernet Sauvignon grape samples exceeded the 1 mg∙L−1 required for the stimulatory effect on ethyl and acetate ester production observed in this study.

  12. Potential grape-derived contributions to volatile ester concentrations in wine.

    Science.gov (United States)

    Boss, Paul K; Pearce, Anthony D; Zhao, Yanjia; Nicholson, Emily L; Dennis, Eric G; Jeffery, David W

    2015-04-29

    Grape composition affects wine flavour and aroma not only through varietal compounds, but also by influencing the production of volatile compounds by yeast. C9 and C12 compounds that potentially influence ethyl ester synthesis during fermentation were studied using a model grape juice medium. It was shown that the addition of free fatty acids, their methyl esters or acyl-carnitine and acyl-amino acid conjugates can increase ethyl ester production in fermentations. The stimulation of ethyl ester production above that of the control was apparent when lower concentrations of the C9 compounds were added to the model musts compared to the C12 compounds. Four amino acids, which are involved in CoA biosynthesis, were also added to model grape juice medium in the absence of pantothenate to test their ability to influence ethyl and acetate ester production. β-Alanine was the only one shown to increase the production of ethyl esters, free fatty acids and acetate esters. The addition of 1 mg∙L(-1) β-alanine was enough to stimulate production of these compounds and addition of up to 100 mg∙L(-1) β-alanine had no greater effect. The endogenous concentrations of β-alanine in fifty Cabernet Sauvignon grape samples exceeded the 1 mg∙L(-1) required for the stimulatory effect on ethyl and acetate ester production observed in this study.

  13. Preparation of polyol esters based on vegetable and animal fats.

    Science.gov (United States)

    Gryglewicz, S; Piechocki, W; Gryglewicz, G

    2003-03-01

    The possibility of using some natural fats: rapeseed oil, olive oil and lard, as starting material for the preparation of neopentyl glycol (NPG) and trimethylol propane (TMP) esters is reported. The syntheses of final products were performed by alcoholysis of fatty acid methyl esters, obtained from natural fats studied, with the appropriate polyhydric alcohol using calcium methoxide as a catalyst. The basic physicochemical properties of the NPG and TMP esters synthesized were the following: viscosity at 40 degrees C in the range of 13.5-37.6 cSt, pour point between -10.5 and -17.5 degrees C and very high viscosity indices, higher than 200. Generally, the esters of neopentyl alcohols were characterized by higher stability in thermo-oxidative conditions in comparison to native triglycerides. Due to the low content of polyunsaturated acids, the olive oil based esters showed the highest thermo-oxidative resistance. Also, methyl esters of fatty acids of lard would constitute a good raw material for the synthesis of lubricating oils, provided that their saturated acids content was lowered. This permits synthesis of NPG and TMP esters with a lower pour point (below -10 degrees C) than natural lard (+33 degrees C).

  14. Occurrence of 3-monochloropropanediol esters and glycidyl esters in commercial infant formulas in the United States.

    Science.gov (United States)

    Leigh, Jessica; MacMahon, Shaun

    2017-03-01

    This work presents occurrence data for fatty acid esters of 3-chloro-1,2-propanediol (3-MCPD) and glycidol in 98 infant formula samples purchased in the United States. These contaminants are considered potentially carcinogenic and/or genotoxic, making their presence in refined oils and foods a potential health risk. Recently, attention has focused on methodology to quantify MCPD and glycidyl esters in infant formula for risk-assessment purposes. Occurrence data for 3-MCPD and glycidyl esters were produced using a procedure for extracting fat from infant formula and an LC-MS/MS method for analysing fat extracts for intact esters. Infant formulas were produced by seven manufacturers, five of which use palm oil and/or palm olein in their formulations. In formulas containing palm/palm olein, concentrations for bound 3-MCPD and glycidol ranged from 0.021 to 0.92 mg kg - 1 (ppm) and from 3-MCPD and glycidol concentrations ranged from 0.072 to 0.16 mg kg - 1 (ppm) and from 0.005 to 0.15 mg kg - 1 (ppm), respectively. Although formulas from manufacturers A and G did not contain palm/palm olein, formulas from manufacturer E (containing palm olein) had the lowest concentrations of bound 3-MCPD and glycidol, demonstrating the effectiveness of industrial mitigation strategies.

  15. ESR studies of high-energy phosphorus-ion implanted synthetic diamond crystals

    Energy Technology Data Exchange (ETDEWEB)

    Isoya, J [University of Library and Information Science, Tsukuba, Ibaraki (Japan); Kanda, H; Morita, Y; Ohshima, T

    1997-03-01

    Phosphorus is among potential n-type dopants in diamond. High pressure synthetic diamond crystals of type IIa implanted with high energy (9-18 MeV) phosphorus ions have been studied by using electron spin resonance (ESR) technique. The intensity and the linewidth of the ESR signal attributed to the dangling bond of the amorphous phase varied with the implantation dose, suggesting the nature of the amorphization varies with the dose. The ESR signals of point defects have been observed in the low dose as-implanted crystals and in the high dose crystals annealed at high temperature and at high pressure. (author)

  16. Performance of fertigation technique for phosphorus application in cotton

    Directory of Open Access Journals (Sweden)

    M. Aslam

    2009-05-01

    Full Text Available Low native soil phosphorus availability coupled with poor utilization of added phosphorus is one of the major constraints limiting the productivity of the crops. With a view of addressing this issue, field studies were conducted to compare the relative efficacy of broadcast and fertigation techniques for phosphorus application during 2005-2006 using cotton as a test crop. Two methods of phosphorus application i.e. broadcast and fertigation were evaluated using five levels of P2O5 (0, 30, 45, 60 and 75 kg P2O5 ha -1. Fertigation showed an edge over broadcast method at all levels of phosphorus application. The highest seed cotton yield was recorded with 75 kg P2O5 ha-1. Fertilizer phosphorus applied at the rate of 60 kg ha-1 through fertigation produced 3.4 tons ha-1 of seed cotton yield, which was statistically identical to 3.3 tons recorded with 75 kg ha-1 of broadcast phosphorus. Agronomic performance of phosphorus was influenced considerably by either method of fertilizer application. The seed cotton yield per kg of fertigation phosphorus was 48% higher than the corresponding broadcast application. The results of these studies showed that fertigation was the most efficient method of phosphorus application compared with the conventional broadcast application of fertilizers.

  17. A Comparison Study: The New Extended Shelf Life Isopropyl Ester PMR Technology versus The Traditional Methyl Ester PMR Approach

    Science.gov (United States)

    Alston, William B.; Scheiman, Daniel A.; Sivko, Gloria S.

    2005-01-01

    Polymerization of Monomeric Reactants (PMR) monomer solutions and carbon cloth prepregs of PMR II-50 and VCAP-75 were prepared using both the traditional limited shelf life methanol based PMR approach and a novel extended shelf life isopropanol based PMR approach. The methyl ester and isopropyl ester based PMR monomer solutions and PMR prepregs were aged for up to four years at freezer and room temperatures. The aging products formed were monitored using high pressure liquid chromatography (HPLC). The composite processing flow characteristics and volatile contents of the aged prepregs were also correlated versus room temperature storage time. Composite processing cycles were developed and six ply cloth laminates were fabricated with prepregs after various extended room temperature storage times. The composites were then evaluated for glass transition temperature (Tg), thermal decomposition temperature (Td), initial flexural strength (FS) and modulus (FM), long term (1000 hours at 316 C) thermal oxidative stability (TOS), and retention of FS and FM after 1000 hours aging at 316 C. The results for each ester system were comparable. Freezer storage was found to prevent the formation of aging products for both ester systems. Room temperature storage of the novel isopropyl ester system increased PMR monomer solution and PMR prepreg shelf life by at least an order of magnitude while maintaining composite properties.

  18. Reaching ultra low phosphorus concentrations by filtration techniques

    NARCIS (Netherlands)

    Scherrenberg, S.M.

    2011-01-01

    This research deals with tertiary treatment techniques used for the removal of phosphorus from wastewater treatment plant (WWTP) effluent. The main objective of this research is to obtain ultra low total phosphorus (<0.15 mg total phosphorus/L) concentrations by coagulation, flocculation and

  19. Cultivation of vetiver in saline tailings contaminated with arsenic under phosphorus doses

    Directory of Open Access Journals (Sweden)

    Lorena A. de O. P. Guimarães

    Full Text Available ABSTRACT The processing of gold ores exploited in Paracatu, MG, generates tailings that are challenging for revegetation, mainly because of the high content of arsenic and salinity. Aiming at the revegetation of the area of disposal of these tailings, the objective of this study was to evaluate the effects of phosphorus doses on vetiver plants (Chrysopogon zizanioides and on the planting substrate, which consisted of tailings from the processing of ore named B1, exploited in Paracatu, with water restriction. Vetiver was grown for four months in the substrate under doses of 0, 140, 280, 560 and 1280 mg kg-1 of P2O5. Increasing doses of phosphorus improved the chemical characteristics of the substrate. However, the highest dose (1280 mg kg-1 P2O5 resulted in higher toxicity of arsenic for the plants. Under the evaluated conditions, the dose of 560 mg kg-1 of P2O5 is the most suitable for the fertilization of vetiver and, therefore, also for the revegetation of the substrate. Vetiver survives under low availability of water in the tailings.

  20. Determination of traces of phosphorus using isotope exchange

    International Nuclear Information System (INIS)

    Zeman, A.; Kratzer, K.

    1976-01-01

    A simple and selective radioanalytical method for the determination of phosphorus (0.015 - 5 μg in a 5 ml sample), based on the heterogeneous isotope exchange, has been developed. The sample containing phosphorus is shaken in the presence of molybdate with a standard solution of tetraphenylarsonium molybdophosphate labelled with phosphorus-32 in 1-2 dicloroethan. From the distribution of the activity between the aqueous and organic phases the amount of phosphorus in the sample can be determined. (Authors)

  1. Patient education for phosphorus management in chronic kidney disease

    Directory of Open Access Journals (Sweden)

    Kalantar-Zadeh K

    2013-05-01

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

  2. The phosphorus and the transition metals chemistry

    International Nuclear Information System (INIS)

    Mathey, F.

    1988-01-01

    The 1988 progress report, concerning the Polytechnic School unit (France), which studies the phosphorus and the transition metals chemistry, is presented. The laboratory activities are related to the following topics: the phosporus heterocyclic chemistry, the phosphorus-carbon double bonds chemistry, the new transition metals phosphorus compounds, the phosphonates and their uses. Some practical applications of homogeneous catalysis and new materials synthesis are investigated. The main results obtained are: the discovery of the tetra-phosphafulvalenes, the utilization of a new synthesis method of the phosphorus-carbon double bonds and the stabilization of the α-phosphonyled carbanions by the lithium diisopropylamidourea. The papers, the congress communications and the thesis are also shown [fr

  3. Management of Natural and Added Dietary Phosphorus Burden in Kidney Disease

    Science.gov (United States)

    Cupisti, Adamasco; Kalantar-Zadeh, Kamyar

    2018-01-01

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

  4. Synthesis of TMP-ester biolubricant basestock from palm stearin fatty acids

    Science.gov (United States)

    Fadzel, Fatimatuzzahraa Mohd; Salimon, Jumat; Derawi, Darfizzi

    2018-04-01

    A potential biolubricant; TMP-ester was produced via esterification of fatty acids (FA) from palm stearin (PS) with trimethylolpropane (TMP). The synthesis was conducted at four conditions; temperature, time, molar ratio of FA:TMP and H2SO4 as catalyst (by percent based on the weight of FA and TMP) that are 150 °C, 2 hours, 4:1 and 1% of H2SO4 respectively. The composition of ester produced was determined using gas chromatography (GC-FID). The presence of ester group was confirmed by the means of FTIR by the existence of strong carboxyl band of ester, v(C=O) at 1746cm-1 and 1H and 13C NMR spectroscopy shows the chemical shift, δ of ester, C=O at 2.27-2.31 ppm and 173.45 ppm accordingly. From the esterification reaction, 95% product of TMP-ester was formed. The thermal and oxidative stability of TMP-ester is 200°C.

  5. Naturally Occurring Cinnamic Acid Sugar Ester Derivatives

    Directory of Open Access Journals (Sweden)

    Yuxin Tian

    2016-10-01

    Full Text Available Cinnamic acid sugar ester derivatives (CASEDs are a class of natural product with one or several phenylacrylic moieties linked with the non-anomeric carbon of a glycosyl skeleton part through ester bonds. Their notable anti-depressant and brains protective activities have made them a topic of great interest over the past several decades. In particular the compound 3′,6-disinapoylsucrose, the index component of Yuanzhi (a well-known Traditional Chinese Medicine or TCM, presents antidepressant effects at a molecular level, and has become a hotspot of research on new lead drug compounds. Several other similar cinnamic acid sugar ester derivatives are reported in traditional medicine as compounds to calm the nerves and display anti-depression and neuroprotective activity. Interestingly, more than one third of CASEDs are distributed in the family Polygalaceae. This overview discusses the isolation of cinnamic acid sugar ester derivatives from plants, together with a systematic discussion of their distribution, chemical structures and properties and pharmacological activities, with the hope of providing references for natural product researchers and draw attention to these interesting compounds.

  6. phosphorus retention data and metadata

    Science.gov (United States)

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

  7. Electrically-inactive phosphorus re-distribution during low temperature annealing

    Science.gov (United States)

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

    2018-04-01

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

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

    Science.gov (United States)

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

    2011-06-01

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

  9. Preparation and characterization of aliphatic diphenyl esters intended as precursors for polyesters

    DEFF Research Database (Denmark)

    Hvilsted, S.; Andruzzi, F.; Cerrai, P.

    1991-01-01

    An extensive number of aliphatic diphenyl esters, C6H5OOC(CH2)nCOOC6H5 (n = O,...,8,10,11,12,14), have been prepared in pure form. The crystalline melting points these esters exhibit an odd-even temperature behaviour, with the higher-melting even series (n even) displaying a minimum for n = 8 while...... based on similar data from phenyl esters, interpreted as the results of an apparent macrocyclic conformation of the larger diphenyl esters. High-performance size exclusion chromatography (s.e.c.) of diphenyl esters, phenyl esters, aromatic and linear hydrocarbons in tetrahydrofuran, toluene...

  10. Prevention of refinery tower plugging by residual oil gellant chemicals in crude-pilot plant evaluation of alternative oil gellants

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, R.S.; Fyten, G.C.; Cheng, A. [Halliburton Energy Services, Calgary, AB (Canada); Stemler, P.S. [Petro-Canada Oil and Gas Inc., Calgary, AB (Canada); Lemieux, A. [Omnicon Consultants Inc., Calgary, AB (Canada)

    2006-07-01

    Tower fouling at petroleum refineries is related to background volatile phosphorus components originating from phosphate ester oil gellants. In an attempt to reduce the cost of unplanned refinery shut downs, the Canadian Association of Petroleum Producers (CAPP) may institute a new specification in July 2006 of 0.5 ppm maximum volatile phosphorus in crude. In concept, volatile phosphorus can be removed from phosphate esters by eliminating volatile components in the original phosphate ester gellant. However, the issue of of whether modified phosphate esters can really reduce refinery tower fouling has been questioned. For that reason, this study focused on water hydrolysis which may occur in a distillation tower, causing localized areas of acidity and causticity. Halogenation reactions could occur in the presence of acid at high temperatures if halogen ions are present. The source of halide ions could be any salts that have not been removed in the de-salters. Full-scale testing at a pilot plant facility was conducted over several days with flowback captured after actual fracturing treatments. Fouling of distillation tower trays was measured along with fouling of the packing material. The study examined how fouling was influenced by changes in operating parameters such as rate, temperature, or pressure during each test. Three full-scale pilot evaluations were conducted using actual flowback fluids from fracturing treatments conducted with 3 different oil gellants: conventional phosphate ester, modified phosphate and phosphonate ester. The comparison of actual tower fouling between these alternative gellants can be used as a guide when choosing oil gellant systems to reduce refinery tower and heat exchanger fouling. It was concluded that phosphonate gellants are hydrolytically stable at higher temperatures and should minimize volatile phosphorus created through the hydrolysis of phosphate esters. However, they are more expensive since they are more complex to create

  11. Method for the determination of natural ester-type gum bases used as food additives via direct analysis of their constituent wax esters using high-temperature GC/MS.

    Science.gov (United States)

    Tada, Atsuko; Ishizuki, Kyoko; Yamazaki, Takeshi; Sugimoto, Naoki; Akiyama, Hiroshi

    2014-07-01

    Natural ester-type gum bases, which are used worldwide as food additives, mainly consist of wax esters composed of long-chain fatty acids and long-chain fatty alcohols. There are many varieties of ester-type gum bases, and thus a useful method for their discrimination is needed in order to establish official specifications and manage their quality control. Herein is reported a rapid and simple method for the analysis of different ester-type gum bases used as food additives by high-temperature gas chromatography/mass spectrometry (GC/MS). With this method, the constituent wax esters in ester-type gum bases can be detected without hydrolysis and derivatization. The method was applied to the determination of 10 types of gum bases, including beeswax, carnauba wax, lanolin, and jojoba wax, and it was demonstrated that the gum bases derived from identical origins have specific and characteristic total ion chromatogram (TIC) patterns and ester compositions. Food additive gum bases were thus distinguished from one another based on their TIC patterns and then more clearly discriminated using simultaneous monitoring of the fragment ions corresponding to the fatty acid moieties of the individual molecular species of the wax esters. This direct high-temperature GC/MS method was shown to be very useful for the rapid and simple discrimination of varieties of ester-type gum bases used as food additives.

  12. Method for the determination of natural ester-type gum bases used as food additives via direct analysis of their constituent wax esters using high-temperature GC/MS

    Science.gov (United States)

    Tada, Atsuko; Ishizuki, Kyoko; Yamazaki, Takeshi; Sugimoto, Naoki; Akiyama, Hiroshi

    2014-01-01

    Natural ester-type gum bases, which are used worldwide as food additives, mainly consist of wax esters composed of long-chain fatty acids and long-chain fatty alcohols. There are many varieties of ester-type gum bases, and thus a useful method for their discrimination is needed in order to establish official specifications and manage their quality control. Herein is reported a rapid and simple method for the analysis of different ester-type gum bases used as food additives by high-temperature gas chromatography/mass spectrometry (GC/MS). With this method, the constituent wax esters in ester-type gum bases can be detected without hydrolysis and derivatization. The method was applied to the determination of 10 types of gum bases, including beeswax, carnauba wax, lanolin, and jojoba wax, and it was demonstrated that the gum bases derived from identical origins have specific and characteristic total ion chromatogram (TIC) patterns and ester compositions. Food additive gum bases were thus distinguished from one another based on their TIC patterns and then more clearly discriminated using simultaneous monitoring of the fragment ions corresponding to the fatty acid moieties of the individual molecular species of the wax esters. This direct high-temperature GC/MS method was shown to be very useful for the rapid and simple discrimination of varieties of ester-type gum bases used as food additives. PMID:25473499

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

    Science.gov (United States)

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

    2017-12-01

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

  14. Phosphorylation of methylene quinones. IV. Reaction of fuchsone and naphthofuchsone with di- and trialkyl phosphites

    International Nuclear Information System (INIS)

    Kopel'tsiv, Yu.A.; Kolesnikov, V.T.; Shermolovich, Yu.G.; Trotsenko, S.I.; Klep, V.Z.

    1986-01-01

    The reaction of fuchsone and naphthofuchsone with dialkyl esters of phosphorus acid was found to follow the 1,6-addition scheme with the formation of dialkyl esters of 4-hydroxytriphenylmethylphosphonic and 4-hydroxynaphthyldiphenylmethylphosphonic acids, respectively. The structure of the reaction products was determined to depend on the nature of the alkyl substituents of the phosphites used. ESR, IR and phosphorus 31 NMR spectra are analyzed and chemical shifts and spin-spin coupling constants are determined

  15. The study of Phosphorus distribution at Putrajaya Wetland

    Science.gov (United States)

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

    2018-04-01

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

  16. Wax ester profiling of seed oil by nano-electrospray ionization tandem mass spectrometry

    Science.gov (United States)

    2013-01-01

    Background Wax esters are highly hydrophobic neutral lipids that are major constituents of the cutin and suberin layer. Moreover they have favorable properties as a commodity for industrial applications. Through transgenic expression of wax ester biosynthetic genes in oilseed crops, it is possible to achieve high level accumulation of defined wax ester compositions within the seed oil to provide a sustainable source for such high value lipids. The fatty alcohol moiety of the wax esters is formed from plant-endogenous acyl-CoAs by the action of fatty acyl reductases (FAR). In a second step the fatty alcohol is condensed with acyl-CoA by a wax synthase (WS) to form a wax ester. In order to evaluate the specificity of wax ester biosynthesis, analytical methods are needed that provide detailed wax ester profiles from complex lipid extracts. Results We present a direct infusion ESI-tandem MS method that allows the semi-quantitative determination of wax ester compositions from complex lipid mixtures covering 784 even chain molecular species. The definition of calibration prototype groups that combine wax esters according to their fragmentation behavior enables fast quantitative analysis by applying multiple reaction monitoring. This provides a tool to analyze wax layer composition or determine whether seeds accumulate a desired wax ester profile. Besides the profiling method, we provide general information on wax ester analysis by the systematic definition of wax ester prototypes according to their collision-induced dissociation spectra. We applied the developed method for wax ester profiling of the well characterized jojoba seed oil and compared the profile with wax ester-accumulating Arabidopsis thaliana expressing the wax ester biosynthetic genes MaFAR and ScWS. Conclusions We developed a fast profiling method for wax ester analysis on the molecular species level. This method is suitable to screen large numbers of transgenic plants as well as other wax ester samples

  17. Electrical activation of phosphorus in silicon

    International Nuclear Information System (INIS)

    Goh, K.E.J.; Oberbeck, L.; Simmons, M.Y.; Clark, R.G.

    2003-01-01

    Full text: We present studies of phosphorus δ-doping in silicon with a view to determining the degree of electrical activation of the dopants. These results have a direct consequence for the use of phosphorus as a qubit in a silicon-based quantum computer such as that proposed by Kane. Room temperature and 4 K Hall effect measurements are presented for phosphorus δ-doped layers grown in n-type silicon using two different methods. In the first method, the δ-layer was deposited by a phosphorus effusion cell in an MBE chamber. In the second method, the Si surface was dosed with phosphine gas and then annealed to 550 deg C to incorporate P into the substrate. In both methods, the P δ-doped layer was subsequently encapsulated by ∼25 nm of Si grown epitaxially. We discuss the implications of our results on the fabrication of the Kane quantum computer

  18. 21 CFR 573.640 - Methyl esters of higher fatty acids.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Methyl esters of higher fatty acids. 573.640... ANIMALS Food Additive Listing § 573.640 Methyl esters of higher fatty acids. The food additive methyl esters of higher fatty acids may be safely used in animal feeds in accordance with the following...

  19. Thermal stabilization and plasticization of poly(vinyl chloride) by ester thiols: Update and current status

    International Nuclear Information System (INIS)

    Starnes, William H.; Du, Bin; Kim, Soungkyoo; Zaikov, Vadim G.; Ge, Xianlong; Culyba, Elizabeth K.

    2006-01-01

    Poly(vinyl chloride) (PVC) is one of the most important medical plastics. Recently, however, the safety of flexible PVC containing the common plasticizer, di(2-ethylhexyl) phthalate, has been called into question. Widely used heat stabilizers for PVC that incorporate toxic heavy metals also have fallen into disfavor. In order to address these problems, we have synthesized and tested, as potential replacements, several organic thiols that contain one or more carboxylate ester functions and thus are highly compatible with the polymer. When introduced into PVC at high loading levels (e.g., 30-35 parts by weight), the ester thiols are extremely effective as heat stabilizers and also useful as primary plasticizers. When used at a low loading level (e.g., 3 parts by weight), they still are excellent heat stabilizers for both plasticized and rigid PVC. Importantly, their high potency is achieved in the absence of any costabilizers that incorporate heavy metals. Their syntheses are simple and straightforward, and their odors are not offensive, because their volatilities are low. Described here are some typical results obtained with this new additive technology, which was licensed for commercialization in 2005

  20. Recovery of phosphorus from sewerage treatment sludge

    Energy Technology Data Exchange (ETDEWEB)

    Manuilova, Anastasia

    1999-07-01

    This thesis is a review of the current state of technologies for the removal of phosphorus from wastewater and sludge, and the recovery and re-use of phosphorus. It explains the need for phosphorus removal and describes the current removal processes. Focus is given to phosphorus crystallisation processes and to the processes which treat sewage treatment sludges into potential sources of phosphorus. An interesting possibility to recover phosphorus from sewage sludge by use of Psenner fractionation is also discussed. By this method, the following phosphate fractions of technological significance may be distinguished: (1) redox sensitive phosphates, mainly bound to Fe(OH){sub 3}; (2) phosphate adsorbed to surfaces (Al{sub 2}O{sub 3}), exchangeable against OH{sup -}, and alkali-soluble phosphate; (3) phosphate bound to CaCO{sub 3}, MgCO{sub 3} and in apatite; and (4) organically bound phosphate. The basic removal mechanisms, process schemes and treatment results are described. Two experiments with three different types of sludges from Henriksdal wastewater treatment plant in Stockholm were performed in the laboratory. It was shown that the addition of sodium hydroxide or hydrochloric acid cause the significant release of phosphate (about 80%) for all types of sludges. If a whole Psenner fractionation was performed the phosphate release is approximately 100%.

  1. Synthesis and investigation of the structure and chemical properties of acyclic compounds of bicoordinated phosphorus with a phosphorus-carbon (p-p)/sub π/ bond

    International Nuclear Information System (INIS)

    Markovskii, L.N.; Romanenko, V.D.

    1987-01-01

    Five types of reactions of phosphoalkenes can be distinguished according to the nature of the change in the coordination number and valence of the phosphorus atom in the course of chemical conversions. There are: reactions of cyclodimerization, cycloaddition, and 1,2-addition at the P-C double bond; formation of compounds of tricoordinated pentavalent phosphorus; formation of tetracoordinated phosphorus compounds; reactions of functionalization occurring without a change in the valence and coordination number of the phosphorus atom; and reactions of 1,2-elimination, leading to compounds of monocoordinated phosphorus. This paper reviews each of these reactions in detail, using double-resonance hydrogen 1 and phosphorus 31 NMR spectra and analyzing the acquired chemical shift and spin-spin coupling constants, and also demonstrates the complexation of phosphorus with several metals

  2. Safety of docosahexaenoic acid (DHA) administered as DHA ethyl ester in a 9-month toxicity study in dogs.

    Science.gov (United States)

    Dahms, Irina; Beilstein, Paul; Bonnette, Kimberly; Salem, Norman

    2016-06-01

    DHA Ethyl Ester (DHA-EE) is a 90% concentrated ethyl ester of docosahexaenoic acid manufactured from the microalgal oil. The objective of the 9-month study was to evaluate safety of DHA-EE administered to beagle dogs at dose levels 150, 1000 and 2000 mg/kg bw/day by oral gavage and to determine reversibility of any findings after a 2-month recovery period. DHA-EE was well tolerated at all doses. There were observations of dry flaky skin with occasional reddened areas at doses ≥1000 mg/kg bw/day. These findings lacked any microscopic correlate and were no longer present after the recovery period. There were no toxicologically relevant findings in body weights, body weight gains, food consumption, ophthalmological examinations, and ECG measurements. Test article-related changes in hematology parameters were limited to decreases in reticulocyte count in the high-dose males and considered non-adverse. In clinical chemistry parameters, dose-related decreases in cholesterol and triglycerides levels were observed at all doses in males and females and attributed to the known lipid-lowering effects of DHA. There were no effects on other clinical chemistry, urinalysis or coagulation parameters. There were no abnormal histopathology findings attributed to test article. The No-Observable-Adverse-Effect Level of DHA-EE was established at 2000 mg/kg bw/day for both genders. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Optimal Use of Plant Stanol Ester in the Management of Hypercholesterolemia

    Directory of Open Access Journals (Sweden)

    Susanna Rosin

    2015-01-01

    Full Text Available Plant stanol ester is a natural compound which is used as a cholesterol-lowering ingredient in functional foods and food supplements. The safety and efficacy of plant stanol ester have been confirmed in more than 70 published clinical studies and the ingredient is a well-established and widely recommended dietary measure to reduce serum cholesterol. Daily intake of 2 g plant stanols as plant stanol ester lowers LDL-cholesterol by 10%, on average. In Europe, foods with added plant stanol ester have been on the market for 20 years, and today such products are also available in many Asian and American countries. Despite the well-documented efficacy, the full potential in cholesterol reduction may not be reached if plant stanol ester is not used according to recommendations. This review therefore concentrates on the optimal use of plant stanol ester as part of dietary management of hypercholesterolemia. For optimal cholesterol lowering aiming at a lower risk of cardiovascular disease, plant stanol ester should be used daily, in sufficient amounts, with a meal and in combination with other recommended dietary changes.

  4. Catalytic Oxidation of Allylic Alcohols to Methyl Esters

    DEFF Research Database (Denmark)

    Gallas-Hulin, Agata; Kotni, Rama Krishna; Nielsen, Martin

    2017-01-01

    Aerobic oxidation of allylic alcohols to methyl esters using gold nanoparticles supported on different metal oxide carriers has been performed successfully under mild conditions (room temperature, 0.1 MPa O2) without significant loss of catalytic activity. The effects of different reaction...... parameters are studied to find the suitable reaction conditions. All catalysts are characterised by XRD, XRF and TEM. Among these catalysts, Au/TiO2 showed the most efficient catalytic activity towards the selective oxidation of allylic alcohols to the corresponding esters. Moreover, the same Au/TiO2...... to synthesize methyl esters from allylic alcohols....

  5. Transformation of Unsaturated Fatty Acids/Esters to Corresponding Keto Fatty Acids/Esters by Aerobic Oxidation with Pd(II)/Lewis Acid Catalyst.

    Science.gov (United States)

    Senan, Ahmed M; Zhang, Sicheng; Zeng, Miao; Chen, Zhuqi; Yin, Guochuan

    2017-08-16

    Utilization of renewable biomass to partly replace the fossil resources in industrial applications has attracted attention due to the limited fossil feedstock with the increased environmental concerns. This work introduced a modified Wacker-type oxidation for transformation of unsaturated fatty acids/esters to the corresponding keto fatty acids/esters, in which Cu 2+ cation was replaced with common nonredox metal ions, that is, a novel Pd(II)/Lewis acid (LA) catalyst. It was found that adding nonredox metal ions can effectively promote Pd(II)-catalyzed oxidation of unsaturated fatty acids/esters to the corresponding keto fatty acids/esters, even much better than Cu 2+ , and the promotional effect is highly dependent on the Lewis acidity of added nonredox metal ions. The improved catalytic efficiency is attributed to the formation of heterobimetallic Pd(II)/LA species, and the oxidation mechanism of this Pd(II)/LA catalyst is also briefly discussed.

  6. Effect of temperature stress on protein methyl esters

    International Nuclear Information System (INIS)

    Welch, W.; Kracaw, K.

    1986-01-01

    Protein methyl esters have been implicated in a number of physiological processes. They have measured the effect of temperature stress on the levels of protein methyl esters in the mesophilic fungus Penicillium chrysogenum (PCPS) and the thermophilic fungus P. duponti (PD). PD and PCPS were incubated with [methyl- 3 H]methionine. The mycelia were collected by filtration, frozen in liquid nitrogen and ground to a fine powder. The nitrogen powder was extracted with either phosphate buffer or with SDS, glycerol, phosphate, 2-mercaptoethanol. Insoluble material was removed by centrifugation. The supernatants were assayed for protein methyl esters. The released [ 3 H]methanol was extracted into toluene:isoamyl alcohol (3:2) and quantitated by liquid scintillation. The production of volatile methanol was confirmed by use of Conway diffusion cells. Soluble proteins accounted for about one-fourth of the total protein methyl ester extracted by SDS. In PCPS, the SDS extracted proteins have about three times the level of esterification of the soluble proteins whereas in PD there is little difference between soluble and SDS extracted protein. The level of protein esterification in PD is about one-tenth that observed in PCPS. Temperature stress caused large changes in the level of protein esterification. The data suggest protein methyl esters may contribute to the adaptation to environmental stress

  7. Lipase catalyzed ester synthesis for food processing industries

    Directory of Open Access Journals (Sweden)

    Aravindan Rajendran

    2009-02-01

    Full Text Available Lipases are one of the most important industrial biocatalyst which catalyzes the hydrolysis of lipids. It can also reverse the reaction at minimum water activity. Because of this pliable nature, it is widely exploited to catalyze the diverse bioconversion reactions, such as hydrolysis, esterification, interesterification, alcoholysis, acidolysis and aminolysis. The property to synthesize the esters from the fatty acids and glycerol promotes its use in various ester synthesis. The esters synthesized by lipase finds applications in numerous fields such as biodiesel production, resolution of the recemic drugs, fat and lipid modification, flavour synthesis, synthesis of enantiopure pharmaceuticals and nutraceuticals. It plays a crucial role in the food processing industries since the process is unaffected by the unwanted side products. Lipase modifications such as the surfactant coating, molecular imprinting to suit for the non-aqueous ester synthesis have also been reported. This review deals with lipase catalyzed ester synthesis, esterification strategies, optimum conditions and their applications in food processing industries.Lipases são catalizadores industriais dos mais importantes, os quais catalizam a hidrólise de lipídeos. Também podem reverter a reação a um mínimo de atividade de água. Devido sua natureza flexível, é amplamente explorada para catalizar uma diversidade de reações de bioconversão como hidrólise, esterificação, interesterificação, alcoólise, acidólise e aminólise. A propriedade de síntese de esteres a partir de ácidos graxos e glicerol promoveu seu uso em várias sínteses de esteres. Os esteres sintetizados por lipases encontram aplicação em numerosos campos como a produção de biodiesel, resolução de drogas racêmicas, modificação de gorduras e lipídios, sintese de aromas, síntese de produtos farmacêuticos enantiopuro e nutracêuticos. As lipases possuem um papel crucial nas indústrias de

  8. The challenge of controlling phosphorus in chronic kidney disease.

    Science.gov (United States)

    Cannata-Andía, Jorge B; Martin, Kevin J

    2016-04-01

    The pathogenesis and management of chronic kidney disease-mineral bone disorders (CKD-MBD) has experienced major changes, but the control of serum phosphorus at all stages of CKD still seems to be a key factor to improve clinical outcomes. High serum phosphorus is the most important uremia-related, non-traditional risk factor associated with vascular calcification in CKD patients and in the general population. Phosphorus may also be one of the key elements linking vascular calcification with low bone turnover. The main hormones and factors that contribute to the kidney regulation of phosphorus and calcium include parathyroid hormone, FGF-23, klotho and 1,25-dihydroxyvitamin D (1,25(OH)2D). Serum phosphorus did not start rising until CKD 3b in contrast with the earlier changes observed with fibroblast growth factor-23 (FGF-23), Klotho, calcitriol and parathyroid hormone (PTH). Despite FGF-23 and PTH having synergic effects regarding phosphorus removal, they have opposite effects on 1,25(OH)2D3. At the same stages of CKD in which phosphorus retention appears to occur, calcium retention also occurs. As phosphorus accumulation is associated with poor outcomes, an important question without a clear answer is at which level-range should serum phosphorus be maintained at different stages of CKD to improve clinical outcomes. There are four main strategies to manage phosphate homeostasis; phosphorus dietary intake, administration of phosphate binder agents, effective control of hyperparathyroidism and to ensure in the CKD 5D setting, an adequate scheme of dialysis. Despite all the available strategies, and the introduction of new phosphate binder agents in the market, controlling serum phosphorus remains challenging, and hyperphosphatemia continues to be extremely common in CKD 5 patients. Furthermore, despite phosphate binding agents having proved to be effective in reducing serum phosphorus, their ultimate effects on clinical outcomes remain controversial. Thus, we still

  9. Availability for plants of phosphorus in some virgin peat samples

    Directory of Open Access Journals (Sweden)

    Armi Kaila

    1958-01-01

    Full Text Available The availability to plants of native peat phosphorus was studied by chemical methods and by a pot experiment in which three successive oat crops were grown with peat as the only source of phosphorus. The eight samples were collected from virgin peat lands. They were air-dried and ground. The samples were found to represent three different types of phosphorus condition: the first group contained relatively high amounts of inorganic phosphorus which was fairly easily available; the second group had a very high capacity to fix phosphorus which made its high quantity of inorganic phosphorus difficultly available; the third group was very poor in total and inorganic phosphorus but the latter was easily soluble and available to plants. On the basis of the capacity and intensity factors determined according to the method by Teräsvuori and also on the basis of inorganic phosphorus extractable by water fairly reliable predictions could be made of the mutual order of the samples as phosphorus supplyer to the plants in the pot experiment. In an incubation experiment at 27°C the amounts of organic phosphorus mineralized during the period of four months were in some of the samples quite marked, even 40 mg/l, and in most of the samples they corresponded to 5 to 15 per cent of the organic phosphorus. The amounts of phosphorus taken up by the oat crops under the favourable conditions of the pot experiment varied from 11 to 60 mg/l or from 20 to 120 kg/ha.

  10. Method for separating mono- and di-octylphenyl phosphoric acid esters

    International Nuclear Information System (INIS)

    Arnold, W.D. Jr.

    1977-01-01

    A method for separating mono-octylphenyl phosphoric acid ester and di-octylphenyl phosphoric acid ester from a mixture thereof comprises reacting the ester mixture with a source of lithium or sodium ions to form a mixture of the phosphate salts; contacting the salt mixture with an organic solvent which causes the dioctylphenyl phosphate salt to be dissolved in the organic solvent phase and the mono-octylphenyl phosphate salt to exist in a solid phase; separating the phases; recovering the phosphate salts from their respective phases; and acidifying the recovered salts to form the original phosphoric acid esters

  11. Recovery of phosphorus compounds from thermally-processed wastes

    Science.gov (United States)

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

    2018-05-01

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

  12. Microbial synthesis of a branched-chain ester platform from organic waste carboxylates

    Directory of Open Access Journals (Sweden)

    Donovan S. Layton

    2016-12-01

    Full Text Available Processing of lignocellulosic biomass or organic wastes produces a plethora of chemicals such as short, linear carboxylic acids, known as carboxylates, derived from anaerobic digestion. While these carboxylates have low values and are inhibitory to microbes during fermentation, they can be biologically upgraded to high-value products. In this study, we expanded our general framework for biological upgrading of carboxylates to branched-chain esters by using three highly active alcohol acyltransferases (AATs for alcohol and acyl CoA condensation and modulating the alcohol moiety from ethanol to isobutanol in the modular chassis cell. With this framework, we demonstrated the production of an ester library comprised of 16 out of all 18 potential esters, including acetate, propionate, butanoate, pentanoate, and hexanoate esters, from the 5 linear, saturated C2-C6 carboxylic acids. Among these esters, 5 new branched-chain esters, including isobutyl acetate, isobutyl propionate, isobutyl butyrate, isobutyl pentanoate, and isobutyl hexanoate were synthesized in vivo. During 24 h in situ fermentation and extraction, one of the engineered strains, EcDL208 harnessing the SAAT of Fragaria ananassa produced ~63 mg/L of a mixture of butyl and isobutyl butyrates from glucose and butyrate co-fermentation and ~127 mg/L of a mixture of isobutyl and pentyl pentanoates from glucose and pentanoate co-fermentation, with high specificity. These butyrate and pentanoate esters are potential drop-in liquid fuels. This study provides better understanding of functional roles of AATs for microbial biosynthesis of branched-chain esters and expands the potential use of these esters as drop-in biofuels beyond their conventional flavor, fragrance, and solvent applications. Keywords: Carboxylate platform, Ester platform, Branched-chain ester, Modular cell, Biological upgrading, Organic waste, Lignocellulosic biomass, Isobutyl esters

  13. Rapid NIR determination of alkyl esters in virgin olive oil

    International Nuclear Information System (INIS)

    Cayuela, J.A.

    2017-01-01

    The regulation of The European Union for olive oil and olive pomace established the limit of 35 mg·kg-1 for fatty acids ethyl ester contents in extra virgin olive oils, from grinding seasons after 2016. In this work, predictive models have been established for measuring fatty acid ethyl and methyl esters and to measure the total fatty acid alkyl esters based on near infrared spectroscopy (NIRS), and used successfully for this purpose. The correlation coefficients from the external validation exercises carried out with these predictive models ranged from 0.84 to 0.91. Different classification tests using the same models for the thresholds 35 mg·kg-1 for fatty acid ethyl esters and 75 mg·kg-1 for fatty acid alkyl esters provided success percentages from 75.0% to 95.2%. [es

  14. Development of tartaric esters as bifunctional additives of methanol-gasoline.

    Science.gov (United States)

    Zhang, Jie; Yang, Changchun; Tang, Ying; Zhou, Rui; Wang, Xiaoli; Xu, Lianghong

    2014-01-01

    Methanol has become an alternative fuel for gasoline, which is facing a rapidly rising world demand with a limited oil supply. Methanol-gasoline has been used in China, but phase stability and vapor lock still need to be resolved in methanol-gasoline applications. In this paper, a series of tartaric esters were synthesized and used as phase stabilizers and saturation vapor pressure depressors for methanol-gasoline. The results showed that the phase stabilities of tartaric esters for methanol-gasoline depend on the length of the alkoxy group. Several tartaric esters were found to be effective in various gasoline-methanol blends, and the tartaric esters display high capacity to depress the saturation vapor pressure of methanol-gasoline. According to the results, it can be concluded that the tartaric esters have great potential to be bifunctional gasoline-methanol additives.

  15. Analysis of Adipate Ester Contents in PVC Plastics

    DEFF Research Database (Denmark)

    Berg, Rolf W.

    2006-01-01

    Plasticizers are needed in flexible PVC (PolyVinylChloride) products. There is serious concern that commonly used phthalate esters may harm life reproduction systems. To avoid the problems, instead adipate di-esters (AEs) of C8 to C10 alcohols are used as higher prized alternatives; e.g. di-2......-ethylhexyl adipate or DEHA [103-23-1], also known as Adimoll® or di-octyl adipate, DOA, see Fig. 1. A widely used plasticizer in food (cling) films is DEHA, often in combination with polymers, epoxidized soya-bean oil, etcetera. DEHA also occurs in children toys. We have previously shown that the presence...... of phthalate esters in PVC can be rapidly analyzed by Fourier transform (FT-) Raman spectroscopy excited with a 1064 nm laser. Here in this project we report a similar study. The aim was to find out whether FT-Raman spectroscopy can be used to determine the presence of adipate esters (AEs) as plasticizers...

  16. Phosphorus in antique iron music wire.

    Science.gov (United States)

    Goodway, M

    1987-05-22

    Harpsichords and other wire-strung musical instruments were made with longer strings about the beginning of the 17th century. This change required stronger music wire. Although these changes coincided with the introduction of the first mass-produced steel (iron alloyed with carbon), carbon was not found in samples of antique iron harpsichord wire. The wire contained an amount of phosphorus sufficient to have impeded its conversion to steel, and may have been drawn from iron rejected for this purpose. The method used to select pig iron for wire drawing ensured the highest possible phosphorus content at a time when its presence in iron was unsuspected. Phosphorus as an alloying element has had the reputation for making steel brittle when worked cold. Nevertheless, in replicating the antique wire, it was found that lowcarbon iron that contained 0.16 percent phosphorus was easily drawn to appropriate gauges and strengths for restringing antique harpsichords.

  17. Interaction between viologen-phosphorus dendrimers and α-synuclein

    International Nuclear Information System (INIS)

    Milowska, Katarzyna; Grochowina, Justyna; Katir, Nadia; El Kadib, Abdelkrim; Majoral, Jean-Pierre; Bryszewska, Maria; Gabryelak, Teresa

    2013-01-01

    In this study the interaction between viologen-phosphorus dendrimers and α-synuclein (ASN) was examined. Polycationic viologen-phosphorus dendrimers (two positive charges per viologen unit) are novel compounds with relatively unknown properties. The influence of these viologen dendrimers on ASN was tested using fluorimetric and circular dichroism methods. ASN contains four tyrosine residues; therefore, the influence of dendrimers on protein molecular conformation by measuring the changes in the ASN fluorescence in the presence of dendrimers was evaluated. The interaction of dendrimers with free L-tyrosine was also monitored. Results show that viologen-phosphorus dendrimers interact with ASN; they quenched the fluorescence of ASN as well as free tyrosine by dynamic and static ways. However, the quenching was not accompanied by modifications in the ASN secondary structure. - Highlights: ► Interaction between viologen-phosphorus dendrimers and α-synuclein (ASN) was investigated. ► Viologen-phosphorus dendrimers can quench the fluorescence of tyrosine in ASN. ► Dendrimers caused red-shift in maximum of fluorescence. ► Viologen-phosphorus dendrimers did not change the secondary structure of ASN.

  18. Ocean acidification: One potential driver of phosphorus eutrophication.

    Science.gov (United States)

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

    2017-02-15

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

  19. Ecotoxicological characterization of polyoxyethylene glycerol ester non-ionic surfactants and their mixtures with anionic and non-ionic surfactants.

    Science.gov (United States)

    Ríos, Francisco; Fernández-Arteaga, Alejandro; Lechuga, Manuela; Fernández-Serrano, Mercedes

    2017-04-01

    This paper reports on a study that investigated the aquatic toxicity of new non-ionic surfactants derived from renewable raw materials, polyoxyethylene glycerol ester (PGE), and their binary mixtures with anionic and non-ionic surfactants. Toxicity of pure PGEs was determined using representative organisms from different trophic levels: luminescent bacteria (Vibrio fischeri), microalgae (Pseudokirchneriella subcapitata), and freshwater crustaceans (Daphnia magna). Relationships between toxicity and the structural parameters such as unit of ethylene oxide (EO) and hydrophilic-lipophilic balance (HLB) were evaluated. Critical micellar concentration (CMC) in the conditions of the toxicity test was also determined. It was found that the toxicity of the aqueous solutions of PGE decreased when the number of EO units in the molecule, HLB, and CMC increased. PGEs showed lower CMC in marine medium, and the toxicity to V. ficheri is lower when the CMC was higher. Given their non-polar nature, narcosis was expected to be the primary mode of toxic action of PGEs. For the mixture of surfactants, we observed that the mixtures with PGE that had the higher numbers of EO units were more toxic than the aqueous solutions of pure surfactants. Moreover, we found that concentration addition was the type of action more likely to occur for mixtures of PGE with lower numbers of EO units with non-ionic surfactants (alkylpolyglucoside and fatty alcohol ethoxylate), whereas for the mixture of PGE with lower EO units and anionic surfactant (ether carboxylic derivative), the most common response type was response addition. In case of mixtures involving amphoteric surfactants and PGEs with the higher numbers of EO units, no clear pattern with regard to the mixture toxicity response type could be observed.

  20. Recycling phosphorus by fast pyrolysis of pig manure: concentration and extraction of phosphorus combined with formation of value-added pyrolysis products

    NARCIS (Netherlands)

    Azuara, M.; Kersten, Sascha R.A.; Kootstra, A.M.J.

    2013-01-01

    In order to recycle phosphorus from the livestock chain back to the land, fast pyrolysis of concentrated pig manure at different temperatures (400 °C, 500 °C, 600 °C), was undertaken to concentrate the phosphorus in the char fraction for recovery. Results show that 92%–97% of the phosphorus present

  1. Vapor-liquid equilibrium for the system ethyl alcohol + ester; Equilibrio liquido-vapor para o sistema alcool etilico+ester

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Humberto Neves Maia de; Nascimento, Yuri Corsino do; Chiavone-Filho, Osvaldo [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2004-07-01

    This work consists of the experimental determination of a series of vapor-liquid equilibrium (VLE) data, for mixtures of ethyl alcohol + ester (ethyl acetate), prepared synthetically, that may be present in the production of biodiesel. The separation of the ethyl alcohol from esters by distillation is an important stage of this process, and therefore it demands accurate data for an appropriate modelling, and later optimization via simulators. FISCHER'S ebulliometer, with digital control (Model 602), was used for measurement of VLE data for the system ethyl alcohol + ester. It consists of a recirculation cell of the both vapor and liquid phases, providing complete data, i.e., pressure, temperature and compositions of the liquid and vapor phases that were obtained by gaseous chromatography (PTxy). This apparatus is coupled to a thermostatic bath with cooling (TE-184 TECNAL) that aims to condense the coming steams of the ebullition in order to return to the mixture camera. The VLE data obtained experimentally were submitted to the test of thermodynamic consistence of the deviations, where the equation of Gibbs-Duhem is used, through the model UNIQUAC. The parameters obtained from the experimental data can be applied in the simulators of processes with the purpose of optimizing the separation of the ethyl alcohol of Ester. (author)

  2. The effects of phosphorus limitation on carbon metabolism in diatoms.

    Science.gov (United States)

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

    2017-09-05

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

  3. Variability of some diterpene esters in coffee beverages as influenced by brewing procedures.

    Science.gov (United States)

    Moeenfard, Marzieh; Erny, Guillaume L; Alves, Arminda

    2016-11-01

    Several coffee brews, including classical and commercial beverages, were analyzed for their diterpene esters content (cafestol and kahweol linoleate, oleate, palmitate and stearate) by high performance liquid chromatography with diode array detector (HPLC-DAD) combined with spectral deconvolution. Due to the coelution of cafestol and kahweol esters at 225 nm, HPLC-DAD did not give accurate quantification of cafestol esters. Accordingly, spectral deconvolution was used to deconvolve the co-migrating profiles. Total cafestol and kahweol esters content of classical coffee brews ranged from 5-232 to 2-1016 mg/L, respectively. Commercial blends contained 1-54 mg/L of total cafestol esters and 2-403 mg/L of total kahweol esters. Boiled coffee had the highest diterpene esters content, while filtered and instant brews showed the lowest concentrations. However, individual diterpene esters content was not affected by brewing procedure as in terms of kahweol esters, kahweol palmitate was the main compound in all samples, followed by kahweol linoleate, oleate and stearate. Higher amounts of cafestol palmitate and stearate were also observed compared to cafestol linoleate and cafestol oleate. The ratio of diterpene esters esterified with unsaturated fatty acids to total diterpene esters was considered as measure of their unsaturation in analyzed samples which varied from 47 to 52%. Providing new information regarding the diterpene esters content and their distribution in coffee brews will allow a better use of coffee as a functional beverage.

  4. Celorbicol, isocelorbicol, and their esters: new sesquiterpenoids from Celastrus orbiculatus

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C.R. Jr. (Dept. of Agriculture, Peoria, IL); Miller, R.W.; Weisleder, D.; Rohwedder, W.K.; Eickman, N.; Clardy, J.

    1976-10-01

    Esters of two new sesquiterpenoid polyalcohols - celorbicol and isocelorbicol - have been isolated from Celastrus orbiculatus. Structures of the parent alcohols have been established by x-ray crystallography, and those of the derived esters have been assigned by NMR spectroscopy. These compounds are structurally related to other polyesters and ester alkaloids from the Celastraceae, all of which are based on the dihydroagarofuran ring system.

  5. ESR study of electron reactions with esters and triglycerides

    International Nuclear Information System (INIS)

    Sevilla, M.D.; Morehouse, K.M.; Swarts, S.

    1981-01-01

    Reactions which occurred after electron attachment at 77K to a number of small carboxylic acid esters and triglycerides in an aqueous glass are reported. Most ester anions are found to decay on warming to form alkyl radicals by β scission: RC(O - )OR' → RCO 2 - + R'.. The alkyl radical (R'.) produced by annealing is found to abstract hydrogen from the parent ester at an α-carbon site, R'.+ R''CH 2 CO 2 R' → R''CHCO 2 R', or in the case of ethyl formate from the formate hydrogen, CH 3 CH 2 .+ HCO 2 C 2 H 5 → C 2 H 6 +.CO 2 C 2 H 5 . Results found for the methyl formate anion suggest hydrogen abstraction by the anion itself may compete with alkyl radical formation. The anion of the triglyceride triacetin is found to undergo an analogous mechanism to the ester anions producing the propane diol diester radical, .CH 2 CH(Ac)CH 2 (Ac), Ac = acetate. This species subsequently abstracts hydrogen from the parent compound to produce the α-carbon radical, .CH 2 CO 2 R. Results found after annealing the tripropionin radical anion give evidence for abstraction from the α carbon in the propionate side groups producing CH 3 CHCO 2 R. Studies of a γ-irradiated ester (ethyl myristate) and two triglycerides (tripalmitin and tristearin) yield results which suggest that the mechanism of ester anion decay found in aqueous glasses applies to γ-irradiated neat long-chain esters and triglycerides. Results found in this work are compared to the results of product analysis

  6. Toxic Cyanobacterial Bloom Triggers in Missisquoi Bay, Lake Champlain, as Determined by Next-Generation Sequencing and Quantitative PCR

    Directory of Open Access Journals (Sweden)

    Nathalie Fortin

    2015-05-01

    Full Text Available Missisquoi Bay (MB is a temperate eutrophic freshwater lake that frequently experiences toxic Microcystis-dominated cyanobacterial blooms. Non-point sources are responsible for the high concentrations of phosphorus and nitrogen in the bay. This study combined data from environmental parameters, E. coli counts, high-throughput sequencing of 16S rRNA gene amplicons, quantitative PCR (16S rRNA and mcyD genes and toxin analyses to identify the main bloom-promoting factors. In 2009, nutrient concentrations correlated with E. coli counts, abundance of total cyanobacterial cells, Microcystis 16S rRNA and mcyD genes and intracellular microcystin. Total and dissolved phosphorus also correlated significantly with rainfall. The major cyanobacterial taxa were members of the orders Chroococcales and Nostocales. The genus Microcystis was the main mcyD-carrier and main microcystin producer. Our results suggested that increasing nutrient concentrations and total nitrogen:total phosphorus (TN:TP ratios approaching 11:1, coupled with an increase in temperature, promoted Microcystis-dominated toxic blooms. Although the importance of nutrient ratios and absolute concentrations on cyanobacterial and Microcystis dynamics have been documented in other laboratories, an optimum TN:TP ratio for Microcystis dominance has not been previously observed in situ. This observation provides further support that nutrient ratios are an important determinant of species composition in natural phytoplankton assemblages.

  7. Phosphorus and nitrogen in the eutrophication of waters

    International Nuclear Information System (INIS)

    Salonen, S.; Frisk, T.; Kaermeniemi, T.; Niemi, J.; Pitkaenen, H.; Silvo, K.; Vuoristo, H.

    1992-01-01

    This report is a summary of the contribution of nitrogen and phosphorus in the eutrophication process of inland and coastal waters. Special attention was paid to the mechanisms of these nutrients in regulating biological processes and to the methods available in estimating their effects in the eutrophication of water bodies. The report includes five chapters which are entitled: Introduction, which is a general background to the subject with special attention to the requirements of the Finnish Water Act. Phosphorus and nitrogen as factors regulating biological processes. The topics included are: definition of eutrophication, forms of phosphorus and nitrogen and their sources to inland and coastal waters, effects of these nutrients as growth factors of phytoplankton and macrophytes and consequences of eutrophication. Estimation of the effects of phosphorus and nitrogen. The topics discussed from the point of view of the tasks of the National Board of Waters and the Environment are: estimation of the effects of phosphorus and nitrogen in the planning and supervision of industry, fish farming, peat production, municipalities, agriculture and forestry. A brief state-of-the art of the research carried out in the National Board of Waters and the Environment is given. Methods of estimating the effects of phosphorus and nitrogen loading in waters. The topics are: relationships between phosphorus and nitrogen concentrations in waters, material balances, water quality models, classification of waters and different groups of organisms as indicators of water quality. Conclusions for the estimation of the effects of phosphorus and nitrogen in receiving waters

  8. Phosphorus solubility in an acid forest soil as influenced by form of applied phosphorus and liming

    International Nuclear Information System (INIS)

    Fransson, Ann-Mari; Bergkvist, Bo; Tyler, Germund

    1999-01-01

    Sedimentary phosphorus, superphosphate, and wood-ash, as well as either sedimentary phosphorus. superphosphate or ash combined with lime, were distributed in selected plots in an 80-yr-old Norway spruce forest [Picea abies (L.) Karst]. After 2 yrs, the sedimentary phosphorus had increased the oxalate/oxalic acid-extractable P in the O-horizon, and the superphosphate had increased the oxalate/oxalic acid-extractable P in the E-horizon. At first, the percolation water from the superphosphate treatment showed high P concentrations. It soon returned to control levels, however. The percolation water from the sedimentary phosphorus treatment gradually showed increased phosphate concentrations. The wood-ash increased neither the amount of extractable P nor the P concentration in the percolation water. The oxalate/oxalic acid-extractable P from the sedimentary P treatment was reduced by liming. The P concentration in the percolation water also tended to be reduced. This was perhaps due to formation of Ca phosphates in the vicinity of the lime particles. In addition, if the solubility rate was similar to the uptake rate, it could account for the decreased P concentration

  9. Integrated co-regulation of bacterial arsenic and phosphorus metabolisms.

    Science.gov (United States)

    Kang, Yoon-Suk; Heinemann, Joshua; Bothner, Brian; Rensing, Christopher; McDermott, Timothy R

    2012-12-01

    Arsenic ranks first on the US Environmental Protection Agency Superfund List of Hazardous Substances. Its mobility and toxicity depend upon chemical speciation, which is significantly driven by microbial redox transformations. Genome sequence-enabled surveys reveal that in many microorganisms genes essential to arsenite (AsIII) oxidation are located immediately adjacent to genes coding for functions associated with phosphorus (Pi) acquisition, implying some type of functional importance to the metabolism of As, Pi or both. We extensively document how expression of genes key to AsIII oxidation and the Pi stress response are intricately co-regulated in the soil bacterium Agrobacterium tumefaciens. These observations significantly expand our understanding of how environmental factors influence microbial AsIII metabolism and contribute to the current discussion of As and P metabolism in the microbial cell. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

  10. Effects of white phosphorus on mallard reproduction

    Science.gov (United States)

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

    2000-01-01

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

  11. Black phosphorus saturable absorber for ultrashort pulse generation

    Energy Technology Data Exchange (ETDEWEB)

    Sotor, J., E-mail: jaroslaw.sotor@pwr.edu.pl; Sobon, G.; Abramski, K. M. [Laser and Fiber Electronics Group, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, Wroclaw 50-370 (Poland); Macherzynski, W.; Paletko, P. [Faculty of Microsystem Electronics and Photonics, Wroclaw University of Technology, Janiszewskiego 11/17, Wroclaw 50-372 (Poland)

    2015-08-03

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

  12. Performance of the mineral blended ester oil-based drilling fluid systems

    Energy Technology Data Exchange (ETDEWEB)

    Ismail, A.R.; Kamis, A.; Foo, K.S. [University Teknologi (Malaysia)

    2001-06-01

    A study was conducted in which the properties of ester oil-based drilling fluid systems were examined using a blended mixture of ester and synthetic mineral oil. Biodegradable invert emulsion ester-based fluids are preferred over mineral oil-based drilling fluids for environmental reasons, but they tend to cause alkaline hydrolysis resulting in solidification of the drilling fluid systems. The drilling fluid examined here consisted of Malaysian palm oil ester derivatives (methyl laureate ester or isopropyl laureate ester) blended with commercially available synthetic mineral oil. This mineral oil was added to reduce the problem of alkaline hydrolysis. This mixture, however, was found to be unstable and could not solve the problem at high temperature. The isopropyl laureate and mineral oil blended system was more stable towards the hydrolysis process up to 250 degrees F. In order to enhance the performance of an invert emulsion drilling fluid system, it was recommended that brine water content of the fluid system be lowered. 3 refs., 2 figs.

  13. Transformation of toxic potential of Jatropha curcas (Ratanjyot into protein source: A mini-review

    Directory of Open Access Journals (Sweden)

    Amit Shukla

    2015-06-01

    Full Text Available The production of animal largely depends on supplying of quality feed and proteinaceous supplement to the animals. Jatropha plant can grow in the barren lands, and are used as a source of biodiesel. Besides, the plant may act as a rich proteinaceous source. However, the antinutritional factors present in the seed and seed oil of the plant may hamper the availability and beneficial use of the plant. Curcin and phorbol esters are the major toxic compounds present in the plant; these toxic compounds cause to produce liver and kidney diseases. Detoxification of these toxic compounds by physical and chemical means converting to less toxic seed cake may serve the purpose of using this plant in future as a replacement of costly protein supplement for animals. Therefore, in modern world, it is recommended to utilize the protein source by neutralizing the antinutritional factors. This mini-review describes the updates on how J. curcas can be utilized as a supplementary source of protein for animals by decreasing its toxicity.

  14. Valyl benzyl ester chloride

    Directory of Open Access Journals (Sweden)

    Grzegorz Dutkiewicz

    2010-02-01

    Full Text Available In the title compound (systematic name: 1-benzyloxy-3-methyl-1-oxobutan-2-aminium chloride, C12H18NO2+·Cl−, the ester group is approximately planar, with a maximum deviation of 0.040 (2 Å from the least-squares plane, and makes a dihedral angle of 28.92 (16° with the phenyl ring. The crystal structure is organized by N—H...Cl hydrogen bonds which join the two components into a chain along the b axis. Pairs of chains arranged antiparallel are interconnected by further N—H...Cl hydrogen bonds, forming eight-membered rings. Similar packing modes have been observed in a number of amino acid ester halides with a short unit-cell parameter of ca 5.5 Å along the direction in which the chains run.

  15. Mefloquine use, psychosis, and violence: a retinoid toxicity hypothesis.

    Science.gov (United States)

    Mawson, Anthony

    2013-07-15

    Mefloquine use has been linked to severe gastrointestinal and neuropsychiatric adverse effects, including cognitive disturbances, anxiety, depression, psychosis, and violence. The adverse effects of the drug are thought to result from the secondary consequences of hepatocellular injury; in fact, mefloquine is known to cause a transient, anicteric chemical hepatitis. However, the mechanism of mefloquine-associated liver damage and the associated neuropsychiatric and behavioral effects of the drug are not well understood. Mefloquine and other 8-amino-quinolines are the only antimalarial drugs that target the liver-stage malaria parasites, which selectively absorb vitamin A from the host. Vitamin A is also stored mainly in the liver, in potentially poisonous concentrations. These observations suggest that both the therapeutic effectiveness of mefloquine and its adverse effects are related to the ability of the 8-aminoquinolines to alter the metabolism of retinoids (vitamin A and its congeners). Several lines of evidence support the hypothesis that mefloquine neurotoxicity and other adverse effects reflect an endogenous form of hypervitaminosis A due to a process involving: mefloquine-induced dehydrogenase inhibition; the accumulation of retinoids in the liver; retinoid-induced hepatocellular damage; the spillage of stored retinoids into the circulation; and the transport of these compounds to the gut and brain in toxic concentrations. The retinoid hypothesis could be tested clinically by comparing cases of mefloquine toxicity and untreated controls in terms of retinoid profiles (retinol, retinyl esters, percent retinyl esters, and retinoic acid). Subject to such tests, retinoid profiling could provide an indicator for assessing mefloquine-associated adverse effects.

  16. Determination of Phthalate Esters in the Aquatic Environment ...

    African Journals Online (AJOL)

    The use of solid phase extraction and capillary GLC provides the basis for selective determination of phthalate ester plasticizers in rivers and marine water samples. Of the several solvent ratios (methanol in dichloromethane) that were tried for selective elution of phthalate esters from the C18 solid phase glass catridge, the ...

  17. Mechanisms and manifestations of toxic actions at the bone tissue level; Mecanismes et manifestations de l'action des toxiques au niveau du tissu osseux

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    The principal abnormalities determined by toxic at the bone level are: osteoporosis, osteomalacia, osteosclerosis or osteopetrosis. The principal toxics having a noxiousness at the bone level are: the fluorine, the phosphorus, the lead, the bismuth, the cadmium and the strontium. The strontium 90 has an important radioactivity that gives at the bone level osteosarcomas or at low doses, leukemoid reactions and marrow angiosarcoma. (N.C.)

  18. Interaction between viologen-phosphorus dendrimers and {alpha}-synuclein

    Energy Technology Data Exchange (ETDEWEB)

    Milowska, Katarzyna, E-mail: milowska@biol.uni.lodz.pl [Department of General Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz (Poland); Grochowina, Justyna [Department of General Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz (Poland); Katir, Nadia [Laboratoire de Chimie de Coordination CNRS, 205 route de Narbonne, 31077 Toulouse (France); El Kadib, Abdelkrim [Institute of Nanomaterials and Nanotechnology (INANOTECH)-MAScIR (Moroccan Foundation for Advanced Science, Innovation and Research), ENSET, Avenue de I' Armee Royale, Madinat El Irfane, 10100 Rabat (Morocco); Majoral, Jean-Pierre [Laboratoire de Chimie de Coordination CNRS, 205 route de Narbonne, 31077 Toulouse (France); Bryszewska, Maria; Gabryelak, Teresa [Department of General Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz (Poland)

    2013-02-15

    In this study the interaction between viologen-phosphorus dendrimers and {alpha}-synuclein (ASN) was examined. Polycationic viologen-phosphorus dendrimers (two positive charges per viologen unit) are novel compounds with relatively unknown properties. The influence of these viologen dendrimers on ASN was tested using fluorimetric and circular dichroism methods. ASN contains four tyrosine residues; therefore, the influence of dendrimers on protein molecular conformation by measuring the changes in the ASN fluorescence in the presence of dendrimers was evaluated. The interaction of dendrimers with free L-tyrosine was also monitored. Results show that viologen-phosphorus dendrimers interact with ASN; they quenched the fluorescence of ASN as well as free tyrosine by dynamic and static ways. However, the quenching was not accompanied by modifications in the ASN secondary structure. - Highlights: Black-Right-Pointing-Pointer Interaction between viologen-phosphorus dendrimers and {alpha}-synuclein (ASN) was investigated. Black-Right-Pointing-Pointer Viologen-phosphorus dendrimers can quench the fluorescence of tyrosine in ASN. Black-Right-Pointing-Pointer Dendrimers caused red-shift in maximum of fluorescence. Black-Right-Pointing-Pointer Viologen-phosphorus dendrimers did not change the secondary structure of ASN.

  19. Radiochemical analysis of phosphorus in milk samples

    International Nuclear Information System (INIS)

    Oliveira, R.M. de; Cunha, I.I.L.

    1991-01-01

    The determination of phosphorus in milk samples by thermal neutron activation analysis employing radiochemical separation is described. The radiochemical separation consists of the simultaneous irradiation of samples and standards, dissolution of the milk samples in a perchloric acid and nitric acid mixture, addition of zinc hold-back carrier, precipitation of phosphorus as ammonium phospho molybdate (A.M.P.) and sample counting in a Geiger-Mueller detector. The analysis sources of error were studied and the established method was applied to phosphorus analyses in commercial milk samples. (author)

  20. ANALYSIS OF ADIPATE ESTER CONTENTS IN POLY(VINYL CHLORIDE) PLASTICS

    DEFF Research Database (Denmark)

    Berg, Rolf W.; Otero, Amalia Dopazo

    2006-01-01

    Fourier transform (FT-) Raman spectroscopy excited with a 1064 nm laser can be used to determine the content of plasticizers in commercial flexible poly vinyl chloride (PVC) products. Our previous study [T. Nørbygaard, R.W. Berg, Analysis of phthalate ester content in PVC plastics by means of FT......-Raman Spectroscopy, Appl. Spectrosc. 58 (4) (2004) 410–413]—on detection of the presence of phthalate esters in PVC by FT-Raman spectroscopy — is here extended to the similar case of adipate esters (AEs) in samples of soft poly vinyl chloride plastics. Spectra of a range of adipate ester plasticizers (11 AEs......) in pure form are reported. We studied if qualitative and quantitative determination of the adipate ester content would be possible based on the use of proper reference samples. It was found that AEs as a group cannot be definitively identified by their characteristic Raman bands because other aliphatic...

  1. Black phosphorus induced photo-doping for high-performance organic-silicon heterojunction photovoltaics

    Institute of Scientific and Technical Information of China (English)

    Zhouhui Xia; Pengfei Li; Yuqiang Liu; Tao Song; Qiaoliang Bao; Shuit-Tong Lee; Baoquan Sun

    2017-01-01

    In conventional crystalline silicon (Si) homojunction solar cells,a strategy of doping by transporting phosphorus or boron impurities into Si is commonly used to build Ohmic contacts at rear electrodes.However,this technique involves an energy intensive,high temperature (~ 800 ℃) process and toxic doping materials.Black phosphorus (BP) is a two-dimensional,narrow bandgap semiconductor with high carrier mobility that exhibits broad light harvesting properties.Here,we place BP:zinc oxide (ZnO) composite films between Si and aluminum (Al) to improve their contact.Once the BP harvests photons with energies below 1.1 eV from the crystalline Si,the ZnO carrier concentration increases dramatically due to charge injection.This photo-induced doping results in a high carrier concentration in the ZnO film,mimicking the modulated doping technique used in semiconductor heterojunctions.We show that photo-induced carriers dramatically increase the conductivities of the BP-modified ZnO films,thus reducing the contact resistance between Si and Al.A photovoltaic power conversion efficiency of 15.2% is achieved in organic-Si heterojunction solar cells that use a ZnO:BP layer.These findings demonstrate an effective way of improving Si/metal contact via a simple,low temperature process.

  2. A new model of anomalous phosphorus diffusion in silicon

    International Nuclear Information System (INIS)

    Budil, M.; Poetzl, H.; Stingeder, G.; Grasserbauer, M.

    1989-01-01

    A model is presented to describe the 'kink and tail' diffusion of phosphorus. The diffusion behaviour of phosphorus is expplained by the motion of phosphorus-interstitial and phosphorus-vacancy pairs in different charge states. The model yields the enhancement of diffusion in the tail region depending on surface concentration. Furthermore it yields the same selfdiffusion coefficient for interstitials as the gold diffusion experiments. A transformation of the diffusion equation was found to reduce the number of simulation equations. (author) 7 refs., 5 figs

  3. Digestible phosphorus levels for barrows from 50 to 80 kg

    Directory of Open Access Journals (Sweden)

    Viviane Maria Oliveira dos Santos Nieto

    2016-05-01

    Full Text Available ABSTRACT This study was carried out to evaluate the levels of digestible phosphorus in diets for barrows with a high potential for lean meat deposition from 50 to 80 kg. Eighty barrows, with an initial weight of 47.93±3.43 kg, were distributed in completely randomized blocks, with each group given five levels of digestible phosphorus (1.86, 2.23, 2.61, 2.99, and 3.36 g kg−1. There were eight replicates, and two animals per experimental unit. Phosphorus levels did not significantly influence feed intake, weight gain, or feed conversion ratio. Daily digestible phosphorus intake increased linearly as levels of phosphorus in the diet were increased. Phosphorus levels did not significantly influence muscle depth, loin eye area, backfat thickness, or the percentage and quantity of lean meat in the carcass. A linear increase was observed for feeding cost as the levels of digestible phosphorus in the diet were increased, and the level of 1.86 g kg−1 cost 29.4% less when compared with the level of 2.61 g kg−1. The dry matter, natural matter, the coefficient of the residue, and volatile solids of the waste were not significantly influenced by phosphorus levels. Conversely, it was possible to observe an increasing linear effect for total solids, total phosphorus, and total nitrogen in the waste of animals receiving diets with increased levels of digestible phosphorus. The level of 1.86 g kg−1, which corresponded to a daily intake of 4.77 g−1 of digestible phosphorus, meets the requirements of barrows weighing 50 to 80 kg.

  4. Lipase-Catalyzed Synthesis of Sugar Esters in Honey and Agave Syrup

    Directory of Open Access Journals (Sweden)

    Sascha Siebenhaller

    2018-02-01

    Full Text Available Honey and agave syrup are high quality natural products and consist of more than 80% sugars. They are used as sweeteners, and are ingredients of cosmetics or medical ointments. Furthermore, both have low water content, are often liquid at room temperature and resemble some known sugar-based deep eutectic solvents (DES. Since it has been shown that it is possible to synthesize sugar esters in these DESs, in the current work honey or, as vegan alternative, agave syrup are used simultaneously as solvent and substrate for the enzymatic sugar ester production. For this purpose, important characteristics of the herein used honey and agave syrup were determined and compared with other available types. Subsequently, an enzymatic transesterification of four fatty acid vinyl esters was accomplished in ordinary honey and agave syrup. Notwithstanding of the high water content for transesterification reactions of the solvent, the successful sugar ester formation was proved by thin-layer chromatography (TLC and compared to a sugar ester which was synthesized in a conventional DES. For a clear verification of the sugar esters, mass determinations by ESI-Q-ToF experiments and a NMR analysis were done. These environmentally friendly produced sugar esters have the potential to be used in cosmetics or pharmaceuticals, or to enhance their effectiveness.

  5. Lipase-Catalyzed Synthesis of Sugar Esters in Honey and Agave Syrup

    Science.gov (United States)

    Siebenhaller, Sascha; Gentes, Julian; Infantes, Alba; Muhle-Goll, Claudia; Kirschhöfer, Frank; Brenner-Weiß, Gerald; Ochsenreither, Katrin; Syldatk, Christoph

    2018-02-01

    Honey and agave syrup are high quality natural products and consist of more than 80% sugars. They are used as sweeteners, and are ingredients of cosmetics or medical ointments. Furthermore, both have low water content, are often liquid at room temperature and resemble some known sugar-based deep eutectic solvents. Since it has been shown that it is possible to synthesize sugar esters in these deep eutectic solvents, in the current work honey or, as vegan alternative, agave syrup are used simultaneously as solvent and substrate for the enzymatic sugar ester production. For this purpose, important characteristics of the herein used honey and agave syrup were determined and compared with other available types. Subsequently, an enzymatic transesterification of four fatty acid vinyl esters was accomplished in ordinary honey and agave syrup. Notwithstanding of the high water content for transesterification reactions of the solvent, the successful sugar ester formation was proved by thin-layer chromatography and compared to a sugar ester which was synthesized in a conventional deep eutectic solvent. For a clear verification of the sugar esters, mass determinations by ESI-Q-ToF experiments and a NMR analysis were done. These environmentally friendly produced sugar esters have the potential to be used in cosmetics or pharmaceuticals, or to enhance their effectiveness.

  6. Chromatography of phosphorus oxoacids

    International Nuclear Information System (INIS)

    Ohashi, S.

    1975-01-01

    The present state of studies on the chromatographic separation of phosphorus oxoacids is surveyed. In this paper, chromatographic techniques are divided into four groups, i.e. paper and thin-layer chromatography, paper electrophoresis, ion-exchange chromatography, and gel chromatography. The separation mechanisms and characteristics for these chromatographic methods are discussed and some examples for the separation of phosphorus oxoacids are described. As examples of the application of ion-exchange and gel chromatography, studies on the hot atom chemistry of 32 P in solid inorganic phosphates and those on the substitution reactions between diphosphonate (diphosphite) and polyphosphates are reported. (author)

  7. Effect of phosphorus level on nitrogen accumulation and yield in soybean

    International Nuclear Information System (INIS)

    You Yubo; Wu Dongmei; Gong Zhenping; Ma Chunmei

    2012-01-01

    In this paper, the 15 N labeling with sand culture was conducted to study effects of phosphorus level on nitrogen accumulation, nodule nitrogen fixation and yield of soybean plants. Results showed that nitrogen accumulation, fixation and yield of soybean plants all presented a single peak curve with improvement of phosphorus nutrition level, with the peak value of phosphorus concentration in nutrient solution of 31 mg/L. When phosphorus concentration of nutrient solution was 11 mg/L, no obvious promotion was found on the ratio of nodule nitrogen fixation when increasing phosphorus concentration again, However, when phosphorus concentration of nutrient solution was 21 mg/L, increasing phosphorus concentration again had no obvious promotion on soybean plant nitrogen accumulation, nodule nitrogen fixation accumulation and yield, indicating that effect of phosphorus nutrition level on nitrogen fixation was lower than that on yield formation level. (authors)

  8. Radiation induced phosphorus segregation in austenitic and ferritic alloys

    International Nuclear Information System (INIS)

    Brimhall, J.L.; Baer, D.R.; Jones, R.H.

    1984-01-01

    The radiation induced surface segregation (RIS) of phosphorus in stainless steel attained a maximum at a dose of 0.8 dpa then decreased continually with dose. This decrease in the surface segregation of phosphorus at high dose levels has been attributed to removal of the phosphorus layer by ion sputtering. Phosphorus is not replenished since essentially all of the phosphorus within the irradiation zone has been segregated to the surface. Sputter removal can explain the previously reported absence of phosphorus segregation in ferritic alloys irradiated at high dosessup(1,2) (>1 dpa) since irradiation of ferritic alloys to low doses has shown measurable RIS. This sputtering phenomenon places an inherent limitation to the heavy ion irradiation technique for the study of surface segregation of impurity elements. The magnitude of the segregation in ferritics is still much less than in stainless steel which can be related to the low damage accumulation in these alloys. (orig.)

  9. Current Strategies for the Detoxification of Jatropha curcas Seed Cake: A Review.

    Science.gov (United States)

    Gomes, Taisa G; Hadi, Sámed I I A; Costa Alves, Gabriel S; Mendonça, Simone; De Siqueira, Felix G; Miller, Robert N G

    2018-03-21

    Jatropha curcas is an important oilseed plant, with considerable potential in the development of biodiesel. Although Jatropha seed cake, the byproduct of oil extraction, is a residue rich in nitrogen, phosphorus, potassium, and carbon, with high protein content suitable for application in animal feed, the presence of toxic phorbol esters limits its application in feed supplements and fertilizers. This review summarizes the current methods available for detoxification of this residue, based upon chemical, physical, biological, or combined processes. The advantages and disadvantages of each process are discussed, and future directions involving genomic and proteomic approaches for advancing our understanding of biodegradation processes involving microorganisms are highlighted.

  10. Isolation and identification of an ester from a crude oil

    Science.gov (United States)

    Phillips, H.F.; Breger, I.A.

    1958-01-01

    A dioctylphthalate has been isolated from a crude oil by means of adsorption column chromatography. The ester was identified by means of elemental analysis, refractive index, and its infra-red absorption spectrum. Saponification of the isolate and examination of the resultant alcohol by means of infrared absorption spectra led to the conclusion that the ester is a branched chain dioctylphthalate. This is the first reported occurrence of an ester in crude petroleum. ?? 1958.

  11. Mutagenic activity of phthalate esters in bacterial liquid suspension assays.

    OpenAIRE

    Seed, J L

    1982-01-01

    The mutagenic activities of several phthalate esters have been evaluated in an 8-azaguanine resistance assay in Salmonella typhimurium. Three phthalate esters were found to be mutagenic: dimethyl phthalate, diethyl phthalate and di-n-butyl phthalate. A number of other phthalate esters were not found to be mutagenic, including di(2-ethylhexyl) phthalate, di-n-octyl phthalate, diallyl phthalate, diisobutyl phthalate and diisodecyl phthalate. A metabolite of di(2-ethylhexyl) phthalate, 2-ethylhe...

  12. Natural Organochlorines as Precursors of 3-Monochloropropanediol Esters in Vegetable Oils.

    Science.gov (United States)

    Tiong, Soon Huat; Saparin, Norliza; Teh, Huey Fang; Ng, Theresa Lee Mei; Md Zain, Mohd Zairey Bin; Neoh, Bee Keat; Md Noor, Ahmadilfitri; Tan, Chin Ping; Lai, Oi Ming; Appleton, David Ross

    2018-01-31

    During high-temperature refining of vegetable oils, 3-monochloropropanediol (3-MCPD) esters, possible carcinogens, are formed from acylglycerol in the presence of a chlorine source. To investigate organochlorine compounds in vegetable oils as possible precursors for 3-MCPD esters, we tested crude palm, soybean, rapeseed, sunflower, corn, coconut, and olive oils for the presence of organochlorine compounds. Having found them in all vegetable oils tested, we focused subsequent study on oil palm products. Analysis of the chlorine isotope mass pattern exhibited in high-resolution mass spectrometry enabled organochlorine compound identification in crude palm oils as constituents of wax esters, fatty acid, diacylglycerols, and sphingolipids, which are produced endogenously in oil palm mesocarp throughout ripening. Analysis of thermal decomposition and changes during refining suggested that these naturally present organochlorine compounds in palm oils and perhaps in other vegetable oils are precursors of 3-MCPD esters. Enrichment and dose-response showed a linear relationship to 3-MCPD ester formation and indicated that the sphingolipid-based organochlorine compounds are the most active precursors of 3-MCPD esters.

  13. Phosphorus conditions at various depths in some mineral soils

    Directory of Open Access Journals (Sweden)

    Armi Kaila

    1963-05-01

    Full Text Available The fractionation method of CHANG and JACKSON (2 was used for the analysing of the distribution of inorganic phosphorus in the topsoil and subsoil of twelve virgin and twelve cultivated soils from various parts of the country; two virgin soils and twenty cultivated soils were studied down to the depths of 60 cm or 70 cm, one even to 2 m. In the more intensively podsolized virgin soils the surface layers, particularly the A2-horizon, are very poor in all the forms of inorganic phosphorus while the enrichment layer will contain fairly high amounts of iron and aluminium bound phosphorus. The application of fertilizers and the other cultivation managements tend to accumulate aluminium and iron bound phosphorus in the plough layer. In some soils the minimum content of calcium bound phosphorus occurs in the layer below the plough layer, but an increase with the depth seems to be typical to it in all the non-Litorina soils, while the first two fractions usually decrease with the depth. In the Litorina soils the iron bound phosphorus is dominant in all the layers studied, but the content of reductant soluble phosphorus is low in these soils, and their content of calcium bound phosphorus is higher than the content of phosphorus bound by aluminium. The predominance of calcium phosphate in the subsoil and the rather low content of reductant soluble and occluded fractions indicate that the chemical weathering in most of our soils is not yet at an advanced stage. The test values determined were in accordance with the results of the fractionation and the estimation of ammonium oxalate soluble aluminium and iron.

  14. Versatile Tri(pyrazolyl)phosphanes as Phosphorus Precursors for the Synthesis of Highly Emitting InP/ZnS Quantum Dots.

    Science.gov (United States)

    Panzer, René; Guhrenz, Chris; Haubold, Danny; Hübner, René; Gaponik, Nikolai; Eychmüller, Alexander; Weigand, Jan J

    2017-11-13

    Tri(pyrazolyl)phosphanes (5 R1,R2 ) are utilized as an alternative, cheap and low-toxic phosphorus source for the convenient synthesis of InP/ZnS quantum dots (QDs). From these precursors, remarkably long-term stable stock solutions (>6 months) of P(OLA) 3 (OLAH=oleylamine) are generated from which the respective pyrazoles are conveniently recovered. P(OLA) 3 acts simultaneously as phosphorus source and reducing agent in the synthesis of highly emitting InP/ZnS core/shell QDs. These QDs are characterized by a spectral range between 530-620 nm and photoluminescence quantum yields (PL QYs) between 51-62 %. A proof-of-concept white light-emitting diode (LED) applying the InP/ZnS QDs as a color-conversion layer was built to demonstrate their applicability and processibility. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. SYNTHESIS OF FATTY ACID ETHYL ESTER FROM CHICKEN FAT ...

    African Journals Online (AJOL)

    eobe

    synthesis of fatty acid ethyl ester from chicken fat waste using ZnO/SiO fatty acid ethyl ester ... obtained in the range of 56−88%and a second order quadratic polynomial regression model that established the ... Transesterification is a chemical.

  16. Analysis of phosphate esters in plant material. Extraction and purification.

    Science.gov (United States)

    Isherwood, F A; Barrett, F C

    1967-09-01

    1. A critical study was made of the quantitative extraction of nucleotide and sugar phosphates from plant tissue by either boiling aqueous ethanol or cold trichloroacetic acid. The effect of the extraction technique on the inactivation of the enzymes in the plant tissue and the possibility of adsorption of the phosphate esters on the cell wall were especially considered. 2. In the recommended method the plant tissue was frozen in liquid nitrogen, ground to a powder and then blended with cold aqueous trichloroacetic acid containing 8-hydroxyquinoline to prevent adsorption. 3. The extract contained large amounts of trichloroacetic acid, cations, chloride, sugars, amino acids, hydroxy organic acids, phytic acid, orthophosphoric acid and high-molecular-weight material including some phosphorus-containing compounds. All of these were removed as they were liable to interfere with the chromatographic or enzymic assay of the individual nucleotide or sugar phosphates. 4. The procedure was as follows: the last traces of trichloroacetic acid were extracted with ether after the solution had been passed through a column of Dowex AG 50 in the hydrogen form to remove all cations. High-molecular-weight compounds were removed by ultrafiltration and low-molecular-weight solutes by a two-stage chromatography on cellulose columns with organic solvents. In the first stage, sugars, amino acids, chloride and phytic acid were separated by using a basic solvent (propan-1-ol-water-aqueous ammonia) and, in the second stage, the organic acids and orthophosphoric acid were separated by using an acidic solvent (di-isopropyl ether-formic acid-2-methylpropan-2-ol-water). The final solution of nucleotide and sugar phosphates was substantially free from other solutes and was suitable for the detection of individual phosphate esters by either chromatography or enzymic assay. 5. The recovery of d-glucose 6-phosphate or adenosine 5'-triphosphate added to a trichloroacetic acid extract simulating that

  17. Influence of ester-modified lipids on bilayer structure.

    Science.gov (United States)

    Villanueva, Diana Y; Lim, Joseph B; Klauda, Jeffery B

    2013-11-19

    Lipid membranes function as barriers for cells to prevent unwanted chemicals from entering the cell and wanted chemicals from leaving. Because of their hydrophobic interior, membranes do not allow water to penetrate beyond the headgroup region. We performed molecular simulations to examine the effects of ester-modified lipids, which contain ester groups along their hydrocarbon chains, on bilayer structure. We chose two lipids from those presented in Menger et al. [J. Am. Chem. Soc. 2006, 128, 14034] with ester groups in (1) the upper half of the lipid chain (MEPC) and (2) the middle and end of the lipid chain (MGPC). MGPC (30%)/POPC bilayers formed stable water pores of diameter 5-7 Å, but MGPC (22%)/POPC and MEPC (30%)/POPC bilayers did not form these defects. These pores were similar to those formed during electroporation; i.e., the head groups lined the pore and allowed water and ions to transport across the bilayer. However, we found that lateral organization of the MGPC lipids into clusters, instead of an electric field or charge disparity as in electroporation, was essential for pore formation. On the basis of this, we propose an overall mechanism for pore formation. The similarities between the ester-modified lipids and byproducts of lipid peroxidation with multiple hydrophilic groups in the middle of the chain suggest that free radical reactions with unsaturated lipids and sterols result in fundamental changes that may be similar to what is seen in bilayers with ester-modified lipids.

  18. Ester Tuiksoo võitleb viina puhtuse eest / Ester Tuiksoo ; interv. Silja Lättemäe

    Index Scriptorium Estoniae

    Tuiksoo, Ester, 1965-

    2006-01-01

    Põllumajandusminister Ester Tuiksoo lubab Euroopa Liidu piiritusjookide määruse eelnõu arutusel kaitsta seisukohta, et viinaks tuleb pidada üksnes teraviljast või kartulist valmistatud piiritusjooki

  19. Iron oxides, divalent cations, silica, and the early earth phosphorus crisis

    DEFF Research Database (Denmark)

    Jones, C.; Nomosatryo, S.; Crowe, S.A.

    2015-01-01

    As a nutrient required for growth, phosphorus regulates the activity of life in the oceans. Iron oxides sorb phosphorus from seawater, and through the Archean and early Proterozoic Eons, massive quantities of iron oxides precipitated from the oceans, producing a record of seawater chemistry...... that is preserved as banded iron formations (BIFs) today. Here we show that Ca2+, Mg2+, and silica in seawater control phosphorus sorption onto iron oxides, influencing the record of seawater phosphorus preserved in BIFs. Using a model for seawater cation chemistry through time, combined with the phosphorus...... waters shifted from phosphorus to iron limiting....

  20. Evaluation of added phosphorus in six volcanic ash soils

    International Nuclear Information System (INIS)

    Pino N, I.; Casas G, L.; Urbinsa P, M.C.

    1984-01-01

    The behaviour of added phosphorus in six volcanic ash soils (Andepts) was studied. Two phosphate retention solution were used; one of them labeled with 32 P carrier free. The phosphate retention solution (25 ml) was added to 5 gr of air dry soil. The remainder phosphorus in solution was measured through colorimetry and liquid scintillation. Over 85% phosphorus retention was measured in five soils. A phosphate retention solution labeled with 32 P carrier free proved to be efficient for the determination of phosphorus retention rates in the volcanic ash soils studied. (Author)

  1. N-[11C]methylpiperidine esters as acetylcholinesterase substrates: an in vivo structure-reactivity study

    International Nuclear Information System (INIS)

    Kilbourn, Michael R.; Nguyen, Thinh B.; Snyder, Scott E.; Sherman, Phillip

    1998-01-01

    A series of simple esters incorporating the N-[ 11 C]methylpiperidine structure were examined as in vivo substrates for acetylcholinesterase in mouse brain. 4-N-[ 11 C]Methylpiperidinyl esters, including the acetate, propionate and isobutyrate esters, are good in vivo substrates for mammalian cholinesterases. Introduction of a methyl group at the 4-position of the 4-piperidinol esters, to form the ester of a teritary alcohol, effectively blocks enzymatic action. Methylation of 4- N-[ 11 C]methylpiperidinyl propionate at the 3-position gives a derivative with increased in vivo reactivity toward acetylcholinesterase. Esters of piperidinecarboxylic acids (nipecotic, isonipecotic and pipecolinic acid ethyl esters) are not hydrolyzed by acetylcholinesterase in vivo, nor do they act as in vivo inhibitors of the enzyme. This study has identified simple methods to both increase and decrease the in vivo reactivity of piperidinyl esters toward acetylcholinesterase

  2. Distribution of phthalate esters in underground water from power ...

    African Journals Online (AJOL)

    This study investigates the distribution of phthalateacid esters (PAEs) in groundwater from some power stations in Delta State. Groundwater samples were collected from eight power transmission and distribution stations. Concentrations (μg/L) of six phthalate acid esters compounds in the groundwater ranged from ...

  3. Synthesis of thermoplastic poly(ester-olefin elastomers

    Directory of Open Access Journals (Sweden)

    Tanasijević Branka

    2004-01-01

    Full Text Available A series of thermoplastic poly(ester-olefin elastomers, based on poly(ethylene-stat-butylene, HO-PEB-OH, as the soft segment and poly (butylene terephthalate, PBT, as the hard segment, were synthesized by a catalyzed transesterification reaction in solution. The incorporation of soft hydrogenated poly(butadiene segments into the copolyester backbone was accomplished by the polycondensation of α, ω-dihydroxyl telechelic HO-PEB-OH, (PEB Mn = 3092 g/mol with 1,4-butanediol (BD and dimethyl terephthalate (DMT in the presence of a 50 wt-% high boiling solvent i.e., 1,2,4-trichlorobenzene. The molar ratio of the starting comonomers was selected to result in a constant hard to soft weight ratio of 60:40. The synthesis was optimized in terms of both the concentration of catalyst, tetra-n-butyl-titanate (Ti(OBu4, and stabilizer, N,N'-diphenyl-p-phenylenediamine (DPPD, as well as the reaction time. It was found that the optimal catalyst concentration (Ti(OBu4 for the synthesis of these thermoplastic elastomers was 1.0 mmol/mol ester and the optimal DPPD concentration was 1.0 wt-%. The extent of the reaction was followed by measuring the inherent viscosity of the reaction mixture. The effectiveness of the incorporation of the soft segments into the copolymer chains was proved by Soxhlet extraction with chloroform. The molecular structures, composition and the size of the synthesized poly(ester-butylenes were verified by 1H NMR spectroscopy, viscometry of dilute solutions and the complex dynamic melt viscosity. The thermal properties of poly(ester-olefins were investigated by differential scanning calorimetry (DSC. The degree of crystallinity was also determined by DSC. The thermal and thermo-oxidative stability were investigated by thermogravimetric analysis (TGA. The rheological properties of poly(ester-olefins were investigated by dynamic mechanical spectroscopy in the melt and solid state.

  4. Potential Grape-Derived Contributions to Volatile Ester Concentrations in Wine

    OpenAIRE

    Boss, Paul; Pearce, Anthony; Zhao, Yanjia; Nicholson, Emily; Dennis, Eric; Jeffery, David

    2015-01-01

    Grape composition affects wine flavour and aroma not only through varietal compounds, but also by influencing the production of volatile compounds by yeast. C9 and C12 compounds that potentially influence ethyl ester synthesis during fermentation were studied using a model grape juice medium. It was shown that the addition of free fatty acids, their methyl esters or acyl-carnitine and acyl-amino acid conjugates can increase ethyl ester production in fermentations. The stimulation of ethyl est...

  5. Isotopically exchangeable phosphorus

    International Nuclear Information System (INIS)

    Barbaro, N.O.

    1984-01-01

    A critique revision of isotope dilution is presented. The concepts and use of exchangeable phosphorus, the phosphate adsorption, the kinetics of isotopic exchange and the equilibrium time in soils are discussed. (M.A.C.) [pt

  6. Ester oxidation on an aluminum surface using chemiluminescence

    Science.gov (United States)

    Jones, William R., Jr.; Meador, Michael A.; Morales, Wilfredo

    1986-01-01

    The oxidation characteristics of a pure ester (trimethyolpropane triheptanoate) were studied by using a chemiluminescence technique. Tests were run in a thin film microoxidation apparatus with an aluminum alloy catalyst. Conditions included a pure oxygen atmosphere and a temperature range of 176 to 206 C. Results indicated that oxidation of the ester (containing .001 M diphenylanthracene as an intensifier) was accompanied by emission of light. The maximum intensity of light emission was a function of the amount of ester, the concentration of intensifier, and the test temperature. The induction period, or the time to reach one-half of maximum intensity was inversely proportional to test temperature. Decreases in light emission at the later stages of a test were caused by depletion of the intensifier.

  7. Neutron activation analysis for calibration of phosphorus implantation dose

    International Nuclear Information System (INIS)

    Paul, Rick L.; Simons, David S.

    2001-01-01

    A feasibility study was undertaken to determine if radiochemical neutron activation analysis (RNAA) can be used to certify the retained dose of phosphorus implanted in silicon, with the goal of producing a phosphorus SRM. Six pieces of silicon, implanted with a nominal phosphorus dose of 8.5x10 14 atoms·cm -2 were irradiated at a neutron flux of 1.05x10 14 cm -2 ·s -1 . The samples were mixed with carrier, dissolved in acid, the phosphorus isolated by chemical separation, and 32 P measured using a beta proportional counter. A mean phosphorus concentration of (8.35±0.20)x10 14 atoms·cm -2 (uncertainty=1 standard deviation) was determined for the six samples, in agreement with the nominal implanted dose

  8. Potential mechanisms of phthalate ester embryotoxicity in the abalone Haliotis diversicolor supertexta

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Jin [L-304, Life Sciences Division, Graduate School at Shenzhen, Tsinghua University, Shenzhen University Town, Xili, Shenzhen City 518055 (China); Cai Zhonghua, E-mail: caizh@sz.tsinghua.edu.cn [L-304, Life Sciences Division, Graduate School at Shenzhen, Tsinghua University, Shenzhen University Town, Xili, Shenzhen City 518055 (China); Key Laboratory of Aquatic-Ecology, Tianjin Agricultural University, Lishui Road 112, Tianjin 300384 (China); Xing Kezhi [Key Laboratory of Aquatic-Ecology, Tianjin Agricultural University, Lishui Road 112, Tianjin 300384 (China)

    2011-05-15

    The effects and associated toxicological mechanisms of five phthalate esters (PAEs) on abalone embryonic development were investigated by exposing the embryos to a range of PAEs concentrations (0.05, 0.2, 2 and 10 {mu}g/mL). The results showed that PAEs could significantly reduce embryo hatchability, increase developmental malformations, and suppress the metamorphosis of abalone larvae. The possible toxicological mechanisms of PAEs to abalone embryos included, affecting the Na{sup +}-K{sup +}-pump and Ca{sup 2+}-Mg{sup 2+}-pump activities, altering the peroxidase (POD) level and the malondialdehyde (MDA) production, damaging the extraembryonic membranes structure, as well as disrupting endocrine-related genes (gpx, cyp3a, and 17{beta}-hsd 12) expression properties. Taken together, this work showed that PAEs adversely affected the embryonic ontogeny of abalone. The abilities of PAEs affecting the osmoregulation, inducing oxidative stress, damaging embryo envelope structure, and causing physiological homeostasis disorder, are likely to be a part of the common mechanisms responsible for their embryonic toxicity. - Highlights: > PAEs affected abalone hatchability, morphogenesis and metamorphosis behavior. > The toxicity of the five PAEs to embryogenesis was ranked as DBP > DEP > DMP > DOP > DEHP. > The osmoregulation disorder and oxidative damage are the potential mechanisms. - Potential mechanisms of PAEs on abalone embryogenesis are osmoregulation disorder, oxidative damage and physiological dysfunction.

  9. Potential mechanisms of phthalate ester embryotoxicity in the abalone Haliotis diversicolor supertexta

    International Nuclear Information System (INIS)

    Zhou Jin; Cai Zhonghua; Xing Kezhi

    2011-01-01

    The effects and associated toxicological mechanisms of five phthalate esters (PAEs) on abalone embryonic development were investigated by exposing the embryos to a range of PAEs concentrations (0.05, 0.2, 2 and 10 μg/mL). The results showed that PAEs could significantly reduce embryo hatchability, increase developmental malformations, and suppress the metamorphosis of abalone larvae. The possible toxicological mechanisms of PAEs to abalone embryos included, affecting the Na + -K + -pump and Ca 2+ -Mg 2+ -pump activities, altering the peroxidase (POD) level and the malondialdehyde (MDA) production, damaging the extraembryonic membranes structure, as well as disrupting endocrine-related genes (gpx, cyp3a, and 17β-hsd 12) expression properties. Taken together, this work showed that PAEs adversely affected the embryonic ontogeny of abalone. The abilities of PAEs affecting the osmoregulation, inducing oxidative stress, damaging embryo envelope structure, and causing physiological homeostasis disorder, are likely to be a part of the common mechanisms responsible for their embryonic toxicity. - Highlights: → PAEs affected abalone hatchability, morphogenesis and metamorphosis behavior. → The toxicity of the five PAEs to embryogenesis was ranked as DBP > DEP > DMP > DOP > DEHP. → The osmoregulation disorder and oxidative damage are the potential mechanisms. - Potential mechanisms of PAEs on abalone embryogenesis are osmoregulation disorder, oxidative damage and physiological dysfunction.

  10. Studies on phosphorus utilization as influenced by bacterial seed inoculation and phosphorus fertilization in summer mung (Vigna radiata L. Wilczek)

    International Nuclear Information System (INIS)

    Kothari, S.K.; Saraf, C.S.

    1988-01-01

    A greenhouse experiment was conducted with four types of bacterial inoculation (Rhizobium alone; Rhizobium along with Azotobacter chroococcum; Rhizobium along with Azospirillum brasilense and no inoculation) and three levels of phosphorus ( 32 P labelled SSP) application (O, 6.5 ppm and 13.0 ppm P). Inoculation with Rhizobium along with Azotobacter chroococcum was found to be better than Rhizobium alone or Rhizobium along with Azospirillum brasilense in respect of leaf, stem, root and nodule dry weight, phosphorus uptake and utilization efficiency. P application upto 6.5 ppm significantly increased leaf, stem, root and nodule dry weight and phosphorus uptake. Per cent phosphorus derived from fertilizer (per cent pdff) and fertilizer P uptake significantly increased while P utilization efficiency significantly decreased with increasing levels of P application. (author). 12 refs., 2 tables

  11. A Lactobacillus plantarum Esterase Active on a Broad Range of Phenolic Esters

    Science.gov (United States)

    Esteban-Torres, María; Landete, José María; Reverón, Inés; Santamaría, Laura; de las Rivas, Blanca

    2015-01-01

    Lactobacillus plantarum is the lactic acid bacterial species most frequently found in the fermentation of food products of plant origin on which phenolic compounds are abundant. L. plantarum strains showed great flexibility in their ability to adapt to different environments and growth substrates. Of 28 L. plantarum strains analyzed, only cultures from 7 strains were able to hydrolyze hydroxycinnamic esters, such as methyl ferulate or methyl caffeate. As revealed by PCR, only these seven strains possessed the est_1092 gene. When the est_1092 gene was introduced into L. plantarum WCFS1 or L. lactis MG1363, their cultures acquired the ability to degrade hydroxycinnamic esters. These results support the suggestion that Est_1092 is the enzyme responsible for the degradation of hydroxycinnamic esters on the L. plantarum strains analyzed. The Est_1092 protein was recombinantly produced and biochemically characterized. Surprisingly, Est_1092 was able to hydrolyze not only hydroxycinnamic esters, since all the phenolic esters assayed were hydrolyzed. Quantitative PCR experiments revealed that the expression of est_1092 was induced in the presence of methyl ferulate, an hydroxycinnamic ester, but was inhibited on methyl gallate, an hydroxybenzoic ester. As Est_1092 is an enzyme active on a broad range of phenolic esters, simultaneously possessing feruloyl esterase and tannase activities, its presence on some L. plantarum strains provides them with additional advantages to survive and grow on plant environments. PMID:25746986

  12. Preferential enrichment of large-sized very low density lipoprotein populations with transferred cholesteryl esters

    International Nuclear Information System (INIS)

    Eisenberg, S.

    1985-01-01

    The effect of lipid transfer proteins on the exchange and transfer of cholesteryl esters from rat plasma HDL2 to human very low (VLDL) and low density (LDL) lipoprotein populations was studied. The use of a combination of radiochemical and chemical methods allowed separate assessment of [ 3 H]cholesteryl ester exchange and of cholesteryl ester transfer. VLDL-I was the preferred acceptor for transferred cholesteryl esters, followed by VLDL-II and VLDL-III. LDL did not acquire cholesteryl esters. The contribution of exchange of [ 3 H]cholesteryl esters to total transfer was highest for LDL and decreased in reverse order along the VLDL density range. Inactivation of lecithin: cholesterol acyltransferase (LCAT) and heating the HDL2 for 60 min at 56 degrees C accelerated transfer and exchange of [ 3 H]cholesteryl esters. Addition of lipid transfer proteins increased cholesterol esterification in all systems. The data demonstrate that large-sized, triglyceride-rich VLDL particles are preferred acceptors for transferred cholesteryl esters. It is suggested that enrichment of very low density lipoproteins with cholesteryl esters reflects the triglyceride content of the particles

  13. Improving phosphorus availability in an acid soil using organic amendments produced from agroindustrial wastes.

    Science.gov (United States)

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

    2014-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Huck Ywih Ch’ng

    2014-01-01

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

  15. Occurrence of phosphorus in groundwater and surface water of northwestern Mississippi

    Science.gov (United States)

    Welch, Heather L.; Kingsbury, James A.; Coupe, Richard H.

    2010-01-01

    Previous localized studies of groundwater samples from the Mississippi River Valley alluvial (MRVA) aquifer have demonstrated that dissolved phosphorus concentrations in the aquifer are much higher than the national background concentration of 0.03 milligram per liter (mg/L) found in 400 shallow wells across the country. Forty-six wells screened in the MRVA aquifer in northwestern Mississippi were sampled from June to October 2010 to characterize the occurrence of phosphorus in the aquifer, as well as the factors that might contribute to high dissolved phosphorus concentrations in groundwater. Dissolved phosphorus concentrations ranged from 0.12 to 1.2 mg/L with a median concentration of 0.62 mg/L. The predominant subunit of the MRVA aquifer in northwestern Mississippi is the Holocene alluvium in which median dissolved phosphorus concentrations were higher than the Pleistocene valley trains deposits subunit. Highest phosphorus concentrations occurred in water from wells located along the Mississippi River. A general association between elevated phosphorus concentrations and dissolved iron concentrations suggests that reducing conditions that mobilize iron in the MRVA aquifer also might facilitate transport of phosphorus. Using baseflow separation to estimate the contribution of baseflow to total streamflow, the estimated contribution to the total phosphorus load associated with baseflow at the Tensas River at Tendal, LA, and at the Bogue Phalia near Leland, MS, was 23 percent and 8 percent, respectively. This analysis indicates that elevated concentrations of dissolved phosphorus in the MRVA aquifer could be a possible source of phosphorus to streams during baseflow conditions. However, the fate of phosphorus in groundwater discharge and irrigation return flow to streams is not well understood.

  16. Secondary poisoning of kestrels by white phosphorus

    Science.gov (United States)

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

    1997-01-01

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

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

    Science.gov (United States)

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

    2017-12-01

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

  18. Phytoextraction of excess soil phosphorus

    International Nuclear Information System (INIS)

    Sharma, Nilesh C.; Starnes, Daniel L.; Sahi, Shivendra V.

    2007-01-01

    In the search for a suitable plant to be used in P phytoremediation, several species belonging to legume, vegetable and herb crops were grown in P-enriched soils, and screened for P accumulation potentials. A large variation in P concentrations of different plant species was observed. Some vegetable species such as cucumber (Cucumis sativus) and yellow squash (Cucurbita pepo var. melopepo) were identified as potential P accumulators with >1% (dry weight) P in their shoots. These plants also displayed a satisfactory biomass accumulation while growing on a high concentration of soil P. The elevated activities of phosphomonoesterase and phytase were observed when plants were grown in P-enriched soils, this possibly contributing to high P acquisition in these species. Sunflower plants also demonstrated an increased shoot P accumulation. This study shows that the phytoextraction of phosphorus can be effective using appropriate plant species. - Crop plants such as cucumber, squash and sunflower accumulate phosphorus and thus can be used in the phytoextraction of excess phosphorus from soils

  19. Phytoextraction of excess soil phosphorus

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Nilesh C. [Department of Biology, Western Kentucky University, 1906 College Heights Boulevard 11080, Bowling Green, KY 42101-1080 (United States); Starnes, Daniel L. [Department of Biology, Western Kentucky University, 1906 College Heights Boulevard 11080, Bowling Green, KY 42101-1080 (United States); Sahi, Shivendra V. [Department of Biology, Western Kentucky University, 1906 College Heights Boulevard 11080, Bowling Green, KY 42101-1080 (United States)]. E-mail: shiv.sahi@wku.edu

    2007-03-15

    In the search for a suitable plant to be used in P phytoremediation, several species belonging to legume, vegetable and herb crops were grown in P-enriched soils, and screened for P accumulation potentials. A large variation in P concentrations of different plant species was observed. Some vegetable species such as cucumber (Cucumis sativus) and yellow squash (Cucurbita pepo var. melopepo) were identified as potential P accumulators with >1% (dry weight) P in their shoots. These plants also displayed a satisfactory biomass accumulation while growing on a high concentration of soil P. The elevated activities of phosphomonoesterase and phytase were observed when plants were grown in P-enriched soils, this possibly contributing to high P acquisition in these species. Sunflower plants also demonstrated an increased shoot P accumulation. This study shows that the phytoextraction of phosphorus can be effective using appropriate plant species. - Crop plants such as cucumber, squash and sunflower accumulate phosphorus and thus can be used in the phytoextraction of excess phosphorus from soils.

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

    Science.gov (United States)

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

    2011-09-01

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

  1. Assessment of Jatropha curcas L. biodiesel seed cake toxicity using the zebrafish (Danio rerio) embryo toxicity (ZFET) test.

    Science.gov (United States)

    Hallare, Arnold V; Ruiz, Paulo Lorenzo S; Cariño, J C Earl D

    2014-05-01

    Consequent to the growing demand for alternative sources of energy, the seeds from Jatropha curcas remain to be the favorite for biodiesel production. However, a significant volume of the residual organic mass (seed cake) is produced during the extraction process, which raises concerns on safe waste disposal. In the present study, we assessed the toxicity of J. curcas seed cake using the zebrafish (Danio rerio) embryotoxicity test. Within 1-h post-fertilization (hpf), the fertilized eggs were exposed to five mass concentrations of J. curcas seed cake and were followed through 24, 48, and 72 hpf. Toxicity was evaluated based on lethal endpoints induced on zebrafish embryos namely egg coagulation, non-formation of somites, and non-detachment of tail. The lowest concentration tested, 1 g/L, was not able to elicit toxicity on embryos whereas 100 % mortality (based also on lethal endpoints) was recorded at the highest concentration at 2.15 g/L. The computed LC50 for the J. curcas seed cake was 1.61 g/L. No further increase in mortality was observed in the succeeding time points (48 and 72 hpf) indicating that J. curcas seed cake exerted acute toxicity on zebrafish embryos. Sublethal endpoints (yolk sac and pericardial edema) were noted at 72 hpf in zebrafish embryos exposed to higher concentrations. The observed lethal endpoints induced on zebrafish embryos were discussed in relation to the active principles, notably, phorbol esters that have remained in the seed cake even after extraction.

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

    Science.gov (United States)

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

    2013-01-01

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

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

    Science.gov (United States)

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

    2013-07-01

    The objective of this study was to determine the prevalence of phosphorus-containing food additives in best-selling processed grocery products and to compare the phosphorus content of a subset of top-selling foods with and without phosphorus additives. The labels of 2394 best-selling branded grocery products in northeast Ohio were reviewed for phosphorus additives. The top 5 best-selling products containing phosphorus additives from each food category were matched with similar products without phosphorus additives and analyzed for phosphorus content. Four days of sample meals consisting of foods with and without phosphorus additives were created, and daily phosphorus and pricing differentials were computed. Presence of phosphorus-containing food additives, phosphorus content. Forty-four percent of the best-selling grocery items contained phosphorus additives. The additives were particularly common in prepared frozen foods (72%), dry food mixes (70%), packaged meat (65%), bread and baked goods (57%), soup (54%), and yogurt (51%) categories. Phosphorus additive-containing foods averaged 67 mg phosphorus/100 g more than matched nonadditive-containing foods (P = .03). Sample meals comprised mostly of phosphorus additive-containing foods had 736 mg more phosphorus per day compared with meals consisting of only additive-free foods. Phosphorus additive-free meals cost an average of $2.00 more per day. Phosphorus additives are common in best-selling processed groceries and contribute significantly to their phosphorus content. Moreover, phosphorus additive foods are less costly than phosphorus additive-free foods. As a result, persons with chronic kidney disease may purchase these popular low-cost groceries and unknowingly increase their intake of highly bioavailable phosphorus. Copyright © 2013 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  4. Phosphorus Processing—Potentials for Higher Efficiency

    Directory of Open Access Journals (Sweden)

    Ludwig Hermann

    2018-05-01

    Full Text Available In the aftermath of the adoption of the Sustainable Development Goals (SDGs and the Paris Agreement (COP21 by virtually all United Nations, producing more with less is imperative. In this context, phosphorus processing, despite its high efficiency compared to other steps in the value chain, needs to be revisited by science and industry. During processing, phosphorus is lost to phosphogypsum, disposed of in stacks globally piling up to 3–4 billion tons and growing by about 200 million tons per year, or directly discharged to the sea. Eutrophication, acidification, and long-term pollution are the environmental impacts of both practices. Economic and regulatory framework conditions determine whether the industry continues wasting phosphorus, pursues efficiency improvements or stops operations altogether. While reviewing current industrial practice and potentials for increasing processing efficiency with lower impact, the article addresses potentially conflicting goals of low energy and material use as well as Life Cycle Assessment (LCA as a tool for evaluating the relative impacts of improvement strategies. Finally, options by which corporations could pro-actively and credibly demonstrate phosphorus stewardship as well as options by which policy makers could enforce improvement without impairing business locations are discussed.

  5. The role of phosphorus sources in the growth of lowland rice plant

    International Nuclear Information System (INIS)

    Sisworo, Widjang Herry

    1975-01-01

    The role of phosphorus sources in the growth of lowland rice plant was studied using P 32 -labelled superphosphate. The experiment was carried out in the glass house. Three high yielding rice varieties used in the experiment were PB 5, IR 22 and Pelita I/1. Results obtained from the experiment showed that, during early growth, seedlings in the nursery did not require any phosphorus from outside. The phosphorus needed was apparently supplied by the seeds themselves. After 10 days seedlings started using phosphorus from outside the plants. Phosphorus in the plants derived from fertilizer reached 5-12% at 16 days old and 25-40% at transplanting time depending on the varieties. Higher response to phosphorus application in the nursery was given by Pelita I/1, the phosphorus in the plants derived from fertilizer was 40% at transplanting time. The phosphorus requirement was mostly supplied by the application of phosphorus fertilizer till 20 days after transplanting but after 40 days soil-phosphorus became the main source for the plants. (author)

  6. Assessment of the acute toxicity of eutrophic sediments after the addition of calcium nitrate (Ibirité reservoir, Minas Gerais-SE Brazil: initial laboratory experiments

    Directory of Open Access Journals (Sweden)

    H. Janke

    Full Text Available This study evaluated the acute toxicity of sediment in a eutrophic reservoir after remediation with a calcium nitrate solution to retain phosphorus. The study involved microcosms of surface sediments and water from the sediment-water interface in the Ibirité reservoir. This reservoir, located in the vicinity of metropolitan Belo Horizonte (Minas Gerais, SE Brazil, is a water body that receives treated effluents from an oil refinery (REGAP-Petrobras, as well as high loads of untreated urban effluents from the city of Ibirité and surrounding areas and industrial effluents from a major industrial park. Incubation times of the treatment experiments were: t = 0, t = 5, t = 10, t = 25, t = 50, t = 85 and t = 135 days. One control microcosm and three treated microcosms were analysed in each time interval. Acute toxicity of water samples was assessed with Ceriodaphnia silvestrii Daday, 1902 and that of bulk sediment samples with Chironomus xanthus Rempel, 1939. Toxicity tests were carried out concomitantly with chemical analyses of dissolved inorganic nitrogen species (ammonia, nitrate and nitrite, sulfate and metals in the water samples of the microcosms. Acid volatile sulfides (AVS, simultaneously extracted metal (SEM and potentially bioavailable metal were analyzed in bulk sediment samples. Neither of the tested organisms showed toxicity in the control microcosm samples. The water column of the treated microcosm showed toxicity to C. silvestrii, starting at t = 10 days, while the sediment pore water toxicity started at t = 0 day. However, toxicity was found to decline from t = 85 days to t = 135 days. Sediments showed toxicity to C. xanthus during the entire experiment, except at the longest incubation time (t = 135 days. The overall results indicate that nitrate, which reached concentrations exceeding 1,200 mg N-NO3- L-1 in the sediment pore water of the treated microcosms, was most probably responsible for the toxicity of the samples. Although

  7. Phosphorus in the feeding of pigs : effect of diet on the absorption and retention of phosphorus by growing pigs

    NARCIS (Netherlands)

    Jongbloed, A.W.

    1987-01-01

    An extensive review is given of the literature concerning phosphorus feeding of pigs. Subjects dealt with are: 1. physiological background, regulation and effect of diet composition and nutrient supply on phosphorus absorption and retention; 2. estimation of the amount of P present in the

  8. Power distribution transformers using natural ester fluids as dielectric and coolant

    Directory of Open Access Journals (Sweden)

    Jorge Iván Silva-Ortega

    2016-12-01

    Full Text Available Researches related to the use of Natural Ester Fluids as a refrigerant of power transformers have been developed in other countries with successful results. In Colombia there is no a procedure to control the use of these esters in electrical apparatus, so the current implementations are regulated by NTC 1465 standards for mineral esters. This new proposal involves the composition and the most relevant properties (the ignition resistance, impact on the lifetime of the insulating papers and the impact on the environment, which makes the application of natural esters fluids advantageous not only to preserve the environment but also to get a better performance of power transformers.

  9. Unsaturated Fatty Acid Esters Metathesis Catalyzed by Silica Supported WMe5

    KAUST Repository

    Riache, Nassima

    2015-11-14

    Metathesis of unsaturated fatty acid esters (FAEs) by silica supported multifunctional W-based catalyst is disclosed. This transformation represents a novel route towards unsaturated di-esters. Especially, the self-metathesis of ethyl undecylenate results almost exclusively on the homo-coupling product whereas with such catalyst, 1-decene gives ISOMET (isomerization and metathesis olefin) products. The olefin metathesis in the presence of esters is very selective without any secondary cross-metathesis products demonstrating that a high selective olefin metathesis could operate at 150 °C. Additionally, a cross-metathesis of unsaturated FAEs and α-olefins allowed the synthesis of the corresponding ester with longer hydrocarbon skeleton without isomerisation.

  10. Influence of iron supply on toxic effects of manganese, molybdenum and vanadium on soybean, peas, and flax

    Energy Technology Data Exchange (ETDEWEB)

    Warington, K

    1954-01-01

    The investigations were carried out in nutrient solution with iron as ferric citrate and nitrogen in the form of nitrate. The addition of 2.5 ppm vanadium to plants in which iron chlorosis was already established, either by a lack of iron or by excess manganese, failed to counteract the condition, and caused toxic symptoms. The reduction of the standard iron supply to 1/2 or 1/3 accentuated the toxicity of 2.5 or 5 ppm V to soybean and flax, but a similar reduction in phosphorus had no influence. The toxicity to peas, however, was increased when the phosphorus was reduced to 1/10, provided the iron level was high (20 ppm Fe). Raising the iron supply to 20 or 30 ppm counteracted the toxicity of manganese (10 ppm), molybdenum (40 ppm) and vanadium (2.5 ppm), but the result was less marked when these three elements were combined. Iron supplied in successive, small doses proved less efficient in overcoming molybdenum or vanadium, but not manganese excess, than the same amount of iron supplied in fewer and larger quantities. Varying the iron supply had little effect when the concentration of the three elements was low. When increased iron supply had reduced the chlorosis caused by high manganese or vanadium, it also reduced the manganese and vanadium contents of the shoot (ppm/dm), but the molybdenum content was only lowered by high iron when given in non-toxic concentrations (0.1 ppm Mo) combined with excess manganese. Yield data for soybean and flax indicated an interaction between manganese with both molybdenum and vanadium if the iron supply was low, but none between molybdenum and vanadium. The effect of all three metals was additive in respect to iron.

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

    Science.gov (United States)

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

    2017-06-14

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

  12. Landfarming of phthalate ester-contaminated soil: Two years of bioremediation results

    International Nuclear Information System (INIS)

    Kunze, C.M.; Yu, J.; Wilson, S.; Rezin, J.L.; Andronico, A.

    1995-01-01

    Biorem Technologies Inc. collaborated with Regal Plastics Corporation over 2 years to clean up approximately 600 cubic yards of soil contaminated with di-2-ethylhexyl phthalate ester (DEHP) and No. 2 fuel oil using a landfarming bioremediation process. The contaminated soils consisted of sandy backfill material which had been excavated during the removal of two underground storage tanks (USTs). In 1994, the initial average DEHP concentration was 4,551 ppm while the TPH concentration was 7,252 ppm. In 1995, the initial DEHP concentration was 1067 ppm while TPH was 3,733 ppm. Prior to the implementation of the project, Biorem Technologies completed a laboratory biofeasibility study to demonstrate that a bacterial culture isolated from the site had the capacity to efficiently degrade DEBP in the soil. It was determined during this study that nitrogen and phosphorus nutrient amendments were needed to promote the bioremediation process. In 1994, the soils were loaded on to a lined treatment bed to a depth of 14--16 in. The bed was covered with a greenhouse structure to eliminate stormwater runoff concerns associated with the contaminated soil. To optimize biodegradation, soil moisture and nutrient levels were adjusted. In 1995, a windrow turner replaced the 1994 tilling system. Tarps were used to cover the piles in place of the greenhouse. A leachate collection system was implemented to contain stormwater and leachate

  13. Overview of phosphorus diffusion and gettering in multicrystalline silicon

    International Nuclear Information System (INIS)

    Bentzen, A.; Holt, A.

    2009-01-01

    This paper gives an overview of phosphorus emitter diffusion and gettering as experienced in multicrystalline silicon solar cell processing. The paper gives a brief summary of the diffusion properties of phosphorus in silicon, explaining the nature behind the characteristic kink-and-tail profiles often encountered in silicon solar cells. Then, phosphorus diffusion gettering is discussed with particular focus to the inhomogeneous nature of multicrystalline silicon, and it is discussed how the abundant presence of dislocations in the areas of the material having a low recombination lifetime can cause only minor lifetime enhancements in such areas upon phosphorus diffusion. Attributed to dissociation of precipitated impurities in combination with longer effective diffusion lengths of the impurities, it is then seen that even poor areas of multicrystalline can exhibit a noticeable improvement by phosphorus diffusion gettering when applying a lower diffusion temperature for a longer duration.

  14. The Potential Phosphorus Crisis: Resource Conservation and Possible Escape Technologies: A Review

    Directory of Open Access Journals (Sweden)

    Saba Daneshgar

    2018-06-01

    Full Text Available Phosphorus is an essential nutrient for every organism on the Earth, yet it is also a potential environmental pollutant, which may cause eutrophication of water bodies. Wastewater treatment plants worldwide are struggling to eliminate phosphorus from effluents, at great cost, yet current research suggests that the world may deplete the more available phosphorus reserves by around 2300. This, in addition to environmental concerns, evokes the need for new phosphorus recovery techniques to be developed, to meet future generations needs for renewable phosphorus supply. Many studies have been, and are, carried out on phosphorus recovery from wastewater and its sludge, due to their high phosphorus content. Chemical precipitation is the main process for achieving a phosphorus-containing mineral suitable for reuse as a fertilizer, such as struvite. This paper reviews the current status and future trends of phosphorus production and consumption, and summarizes current recovery technologies, discussing their possible integration into wastewater treatment processes, according to a more sustainable water-energy-nutrient nexus.

  15. Critical aggregates concentration of fatty esters present in biodiesel determined by turbidity and fluorescence.

    Science.gov (United States)

    Froehner, Sandro; Sánez, Juan; Dombroski, Luiz Fernando; Gracioto, Maria Paula

    2017-09-01

    Biodiesel for combustible engine is available as mixture of fossil diesel and fatty esters obtained by transesterification of vegetable oils. The use of biodiesel reduces the amount of SO x , mainly. However, it was already observed that biodiesel has a different behavior in environment in cases of accidental spill and groundwater contamination. It was noticed that the biodegradation of hydrocarbons (cyclic and aliphatic) in the presence of biodiesel are speeded, although the mechanism is still unclear. Considering the chemical structure of fatty esters, it was investigated the formation of aggregates in water solution by fatty esters present in commercial biodiesel. In Brazil, biodiesel is composed by 95% of fossil diesel and 5% of fatty esters mixture. In this work, fatty esters were treated as neutral surfactant, i.e., it was treated as a molecule with polar and non-polar part. Turbidity and fluorescence were used to determine the critical aggregates concentration (CAC). Water solutions containing fatty esters were examined exploiting changes in turbidity and fluorescence intensity of pyrene. Abrupt changes were attributed to aggregates formation, following the same behavior of traditional amphiphilic compounds. It was determined the CAC for ethyl palmitate, ethyl stearate, ethyl oleate, and ethyl linoleate. The values of CAC for fatty esters varied from 1.91 to 4.27 μmol/L, while CAC for the mixture of esters (biodiesel) was 2.01 for methyl esters and 1.19 for ethyl esters, both prepared using soybean oil. The aggregates formation was also determined by fluorescence measurements considering the changes in intensity of peaks I and III of pyrene. Pyrene senses the changes in environment polarity. The values found of CAC by fluorescence for individual ethyl esters varied from 1.85 to 3.21 μmol/L, while mixtures of ethyl esters was 2.23 and 2.07 μmol/L for mixture of methyl esters. The results clearly showed that fatty esters form aggregates and might be

  16. Half esters and coating compositions comprising reactions products of half esters and polyepoxides

    NARCIS (Netherlands)

    Blaauw, R.; Mulder, W.J.; Koelewijn, R.; Boswinkel, G.

    2006-01-01

    The present invention relates to half esters based on dicarboxylic acid derivatives and dimer fatty diols, wherein the dimer fatty dio ls are based on dimerised and/or trimerised and/or oligomerised unsaturated fatty acids. The present invention further relates to resin compositions based on the

  17. Structure of inorganic phosphorus-nitrogen tetrahedral compounds

    International Nuclear Information System (INIS)

    Vitola, A.; Ronis, J.; Avotins, V.; Millers, T.

    1997-01-01

    The structure analysis of phosphorus-nitrogen compounds has shown the possibility of the P(O,N) 4 tetrahedra to form various kinds of structures. The wide spectrum of the properties determined by the diversity of structures marks the considerable promise to the future application of phosphorus-nitrogen compounds

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

    Science.gov (United States)

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

    2015-08-15

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

  19. Catalytic Ester and Amide to Amine Interconversion: Nickel-Catalyzed Decarbonylative Amination of Esters and Amides by C−O and C−C Bond Activation

    KAUST Repository

    Yue, Huifeng

    2017-03-15

    An efficient nickel-catalyzed decarbonylative amination reaction of aryl and heteroaryl esters has been achieved for the first time. The new amination protocol allows the direct interconversion of esters and amides into the corresponding amines and represents a good alternative to classical rearrangements as well as cross coupling reactions.

  20. Catalytic Ester and Amide to Amine Interconversion: Nickel-Catalyzed Decarbonylative Amination of Esters and Amides by C−O and C−C Bond Activation

    KAUST Repository

    Yue, Huifeng; Guo, Lin; Liao, Hsuan-Hung; Cai, Yunfei; Zhu, Chen; Rueping, Magnus

    2017-01-01

    An efficient nickel-catalyzed decarbonylative amination reaction of aryl and heteroaryl esters has been achieved for the first time. The new amination protocol allows the direct interconversion of esters and amides into the corresponding amines and represents a good alternative to classical rearrangements as well as cross coupling reactions.

  1. 21 CFR 573.660 - Methyl glucoside-coconut oil ester.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Methyl glucoside-coconut oil ester. 573.660 Section 573.660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... ANIMALS Food Additive Listing § 573.660 Methyl glucoside-coconut oil ester. Methyl glucoside-coconut oil...

  2. Ocular Pharmacokinetics of Acyclovir Amino Acid Ester Prodrugs in the Anterior Chamber: Evaluation of Their Utility in Treating Ocular HSV Infections

    Science.gov (United States)

    Katragadda, Suresh; Gunda, Sriram; Hariharan, Sudharshan; Mitra, Ashim K.

    2008-01-01

    Purpose To evaluate in vivo corneal absorption of the amino acid prodrugs of acyclovir (ACV) using a topical well model and microdialysis in rabbits. Methods Stability of L-Alanine-ACV (AACV), L-Serine-ACV (SACV), L-Isoleucine-ACV (IACV), γ-Glutamate-ACV (EACV) and L-Valine-ACV (VACV) prodrugs was evaluated in various ocular tissues. Dose dependent toxicity of these prodrugs was also examined in rabbit primary corneal epithelial cell culture (rPCEC) using 96-well based cell proliferation assay. In vivo ocular bioavailability of these compounds was also evaluated with a combination of topical well infusion and aqueous humor microdialysis techniques. Results Among the amino acid ester prodrugs, SACV was most stable in aqueous humor. Enzymatic degradation of EACV was the least compared to all other prodrugs. Cellular toxicity of all the prodrugs was significantly less compared to trifluorothymidine (TFT) at 5mM. Absorption rate constants of all the compounds were found to be lower than the elimination rate constants. All the prodrugs showed similar terminal elimination rate constants (λz). SACV and VACV exhibited approximately two fold increase in area under the curve (AUC) relative to ACV (p cornea at varying rates (ka) thereby leading to varying extents (AUC). The amino acid ester prodrug, SACV owing to its enhanced stability, comparable AUC, and high concentration at last time point (Clast) seems to be a promising candidate for the treatment of ocular HSV infections. PMID:18472234

  3. A Lactobacillus plantarum esterase active on a broad range of phenolic esters.

    Science.gov (United States)

    Esteban-Torres, María; Landete, José María; Reverón, Inés; Santamaría, Laura; de las Rivas, Blanca; Muñoz, Rosario

    2015-05-01

    Lactobacillus plantarum is the lactic acid bacterial species most frequently found in the fermentation of food products of plant origin on which phenolic compounds are abundant. L. plantarum strains showed great flexibility in their ability to adapt to different environments and growth substrates. Of 28 L. plantarum strains analyzed, only cultures from 7 strains were able to hydrolyze hydroxycinnamic esters, such as methyl ferulate or methyl caffeate. As revealed by PCR, only these seven strains possessed the est_1092 gene. When the est_1092 gene was introduced into L. plantarum WCFS1 or L. lactis MG1363, their cultures acquired the ability to degrade hydroxycinnamic esters. These results support the suggestion that Est_1092 is the enzyme responsible for the degradation of hydroxycinnamic esters on the L. plantarum strains analyzed. The Est_1092 protein was recombinantly produced and biochemically characterized. Surprisingly, Est_1092 was able to hydrolyze not only hydroxycinnamic esters, since all the phenolic esters assayed were hydrolyzed. Quantitative PCR experiments revealed that the expression of est_1092 was induced in the presence of methyl ferulate, an hydroxycinnamic ester, but was inhibited on methyl gallate, an hydroxybenzoic ester. As Est_1092 is an enzyme active on a broad range of phenolic esters, simultaneously possessing feruloyl esterase and tannase activities, its presence on some L. plantarum strains provides them with additional advantages to survive and grow on plant environments. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  4. KARAKTERISTIK EMULSI SANTAN DAN MINYAK KEDELAI YANG DITAMBAH GUM ARAB DAN SUKROSA ESTER [Emulsion Characteristics of Coconut Milk and Soybean Oil Added with Gum Arabic and Sucrose Ester

    Directory of Open Access Journals (Sweden)

    Laksmi Hartayanie

    2015-07-01

    Full Text Available High saturated fatty acid content in coconut milk can be reduced by adding unsaturated fat. Pretreatment such as pasteurisation, homogenization or stabilizer and emulsifier addition are essential to prevent emulsion deterioration that could happen in few hours. This study aimed to determine the most appropriate combination of gum arabic and sucrose ester to produce good emulsion stability based on its physical and chemical characteristics. Furthermore this study also aimed to determine correlation between creaming index and other characteristics of coconut milk emulsion. Emulsion stability of mixed coconut milk in sterile glass bottles was observed for 7 days under 23-24°C. Stabilizer and emulsifier added were gum arabic and sucrose ester in five combinations, i.e. 6% gum arabic, 0.3% sucrose ester, 6% gum arabic + 0.3% sucrose ester, 3% gum arabic + 0.15% sucrose ester and 4.5% gum arabic + 0.225% sucrose ester. The physical characteristics evaluated were creaming index, total color change, viscosity and droplet distribution, while the chemical characteristics observed included pH, TBA value, and protein content. Data were analyzed by One Way Anova at 95% significant level to determine the differences among treatments. Bivariate Pearson Correlation was used in order to determine the interaction among sample characteristics. The data showed that, gum arabic and sucrose ester can maintain the emulsion stability. A combination of 4.5% gum arabic and 0.225% sucrose ester provided the best physicochemical characteristics with the lowest creaming index and decreased viscosit, and uniform droplet distribution.

  5. Direct observation of thermal disorder and decomposition of black phosphorus

    Science.gov (United States)

    Yoo, Seung Jo; Kim, Heejin; Lee, Ji-Hyun; Kim, Jin-Gyu

    2018-02-01

    Theoretical research has been devoted to reveal the properties of black phosphorus as a two-dimensional nanomaterial, but little attention has been paid for the experimental characterization. In this study, the thermal disorder and decomposition of black phosphorus were examined using in situ heating transmission electron microscopy experiments. We observed that the breaking of crystallographic symmetry begins at 380 °C under vacuum condition, followed by the phosphorus evaporates after long-term heating at 400 °C. This decomposition process can be initiated by the surficial vacancy and proceeds toward both interlayer ([010]) and intralayer ([001]) directions. The results on the thermal behavior of black phosphorus provide useful guidance for thin film deposition and fabrication processes with black phosphorus.

  6. Measurement of phosphorus in metals by RNAA

    International Nuclear Information System (INIS)

    Paul, R.L.

    2000-01-01

    An RNAA procedure has been developed for measurement of low-level phosphorus in metals. Samples are irradiated at a neutron flux of 2.7 x 10 13 n x cm -2 x s -1 then mixed with carrier and dissolved in acid. After chemical separation and purification of the phosphorus and gravimetric determination of carrier yield, 32 P is determined using a beta proportional counter. The detection limit for a 0.1 g sample irradiated for 30 minutes is 5 μg/kg. The method has been used to determine 6.4 ± 0.6 mg/kg phosphorus is SRM 2175 refractory alloy. (author)

  7. Determination of 3-Monochloropropane-1,2-diol and 2-Monochloropropane-1,3-diol (MCPD) Esters and Glycidyl Esters by Microwave Extraction in Different Foodstuffs.

    Science.gov (United States)

    Marc, Corinne; Drouard-Pascarel, Valérie; Rétho, Cécile; Janvion, Patrice; Saltron, Frédéric

    2016-06-01

    This paper describes a method for the determination of 3-monochloropropane-1,2-diol and 2-monochloropropane-1,3-diol (MCPD) esters and glycidyl esters in various foodstuffs, which are isolated using microwave extraction. The next step is based on alkaline-catalyzed ester cleavage. The released glycidol is transformed into monobromopropanediol (MBPD). All compounds are derivatized in free diols (MCPD and MBPD) with phenylboronic acid and analyzed by gas chromatography-mass spectrometry (GC-MS). The method was validated for oils with a limit of quantitation (LOQ) of 0.1 mg/kg, for chips and crisps with a LOQ of 0.02 mg/kg, and for infant formula with a LOQ of 0.0025 mg/L. Recoveries of each sample were controlled by standard addition on extracts before derivatization. Quantitation was performed by the addition of isotopically labeled glycidyl and 3-monochloropropane-1,2-diol (3-MCPD) esters.

  8. Identification of cowpea cultivars for low phosphorus soils of Nigeria

    International Nuclear Information System (INIS)

    Afolabi, N.O.; Ogunbodede, B.A.; Adediran, J.A.

    1996-01-01

    Twenty cultivars of cowpea, Vigna unguiculata, adapted to the Nigerian ecologies were screened to identify cultivars which can give high and sustainable yields when grown on soils with low available phosphorus in a sub-humid climate. Some cultivars including TVX3236, AFB1757, Ogunfowokan and K-28 gave three to four times higher grain yields than the other cultivars at zero phosphorus supply. While phosphorus application reduced grain yield in most of the cultivars with marked reduction in the higher yielding cultivars, low yielding cultivars tended to show some yield increase. Phosphorus use efficiency of the roots, stem or leaves was not significantly correlated with grain yield when 60 KgP/ha was applied. Reduction in yield due to phosphorus application might be due to induced Zn deficiency as Zn supply in these soils has been found to be inherently low. High grain yielding capacity without fertilizer phosphorus application was generally positively correlated with high vegetative shoot dry matter production. However, no clear relationship could be found between grain yield and root dry matter at maturity. It is concluded that selection for phosphorus efficiency in cowpea can substantially contribute to higher cowpea productivity and the farmers income on soils low in available phosphorus in the sub-humid areas of Nigeria. (author). 5 refs, 2 figs, 2 tabs

  9. Identification of cowpea cultivars for low phosphorus soils of Nigeria

    Energy Technology Data Exchange (ETDEWEB)

    Afolabi, N O; Ogunbodede, B A; Adediran, J A [Obafemi Awolowo Univ., Ibadan (Nigeria). Inst. of Agricultural Research and Training

    1996-07-01

    Twenty cultivars of cowpea, Vigna unguiculata, adapted to the Nigerian ecologies were screened to identify cultivars which can give high and sustainable yields when grown on soils with low available phosphorus in a sub-humid climate. Some cultivars including TVX3236, AFB1757, Ogunfowokan and K-28 gave three to four times higher grain yields than the other cultivars at zero phosphorus supply. While phosphorus application reduced grain yield in most of the cultivars with marked reduction in the higher yielding cultivars, low yielding cultivars tended to show some yield increase. Phosphorus use efficiency of the roots, stem or leaves was not significantly correlated with grain yield when 60 KgP/ha was applied. Reduction in yield due to phosphorus application might be due to induced Zn deficiency as Zn supply in these soils has been found to be inherently low. High grain yielding capacity without fertilizer phosphorus application was generally positively correlated with high vegetative shoot dry matter production. However, no clear relationship could be found between grain yield and root dry matter at maturity. It is concluded that selection for phosphorus efficiency in cowpea can substantially contribute to higher cowpea productivity and the farmers income on soils low in available phosphorus in the sub-humid areas of Nigeria. (author). 5 refs, 2 figs, 2 tabs.

  10. Alternative Production of Fatty Acid Methyl Esters from Triglycerides ...

    African Journals Online (AJOL)

    The catalysts activity was tested in thermocatalytic cracking of triglyceride; a direct conversion process for fatty acid methyl esters (biodiesel). The SZ1 not only exhibited higher conversion of triglycerides but higher fatty acid methyl esters (FAMEs) yields of approximately 59% after 3h as compared to SZ2 (32%). In addition ...

  11. Quantitation of phosphorus excretion in sheep by compartmental analysis

    International Nuclear Information System (INIS)

    Schneider, K.M.; Boston, R.C.; Leaver, D.D.

    1987-01-01

    The control of phosphorus excretion in sheep has been examined by constructing a kinetic model that contains a mechanistic set of connections between blood and gastrointestinal tract. The model was developed using experimental data from chaff-fed sheep and gives an accurate description of the absorption and excretion of 32 P phosphorus in feces and urine of the ruminating sheep. These results indicated the main control site for phosphorus excretion in the ruminating sheep was the gastrointestinal tract, whereas for the non-ruminating sheep fed the liquid diet, control was exerted by the kidney. A critical factor in the induction of adaptation of phosphorus reabsorption by the kidney was the reduction in salivation, and since this response occurred independently of marked changes in the delivery of phosphorus to the kidney, a humoral factor may be involved in this communication between salivary gland and kidney

  12. Steryl ester synthesis, storage and hydrolysis: A contribution to sterol homeostasis.

    Science.gov (United States)

    Korber, Martina; Klein, Isabella; Daum, Günther

    2017-12-01

    Sterols are essential lipids of all eukaryotic cells, appearing either as free sterols or steryl esters. Besides other regulatory mechanisms, esterification of sterols and hydrolysis of steryl esters serve to buffer both an excess and a lack of free sterols. In this review, the esterification process, the storage of steryl esters and their mobilization will be described. Several model organisms are discussed but the focus was set on mammals and the yeast Saccharomyces cerevisiae. The contribution of imbalanced cholesterol homeostasis to several human diseases, namely Wolman disease, cholesteryl ester storage disease, atherosclerosis and Alzheimer's disease, Niemann-Pick type C and Tangier disease is described. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Effect of phytase supplementation on apparent phosphorus digestibility and phosphorus output in broiler chicks fed low-phosphorus diets

    Directory of Open Access Journals (Sweden)

    Xian-Ren Jiang

    2015-04-01

    Full Text Available This study was conducted to evaluate the effect of supplemental phytase in broiler chicks fed different low levels of total phosphorus (P on the apparent phosphorus digestibility (APD and phosphorus output (PO in the faeces and ileal digesta. After fed a standard broiler starter diet from day 0 to 14 post-hatch, a total of 144 male broiler chicks were allocated to 6 groups for a 7-d experiment with a 2 × 3 factorial design comparing phytase (supplemented without (CTR or with 400 FTU/kg phytase (PHY and total P levels (2.0, 2.5 and 3.0 g/kg. The faecal samples were collected from day 17 to 21 post-hatch. At 22 days of age, all the chicks were slaughtered and collected the ileal digesta. Phytase supplementation significantly (P < 0.01 increased APD and decreased PO in the faeces and ileal digesta in comparison with the CTR group. In addition, PO in the faeces expressed as g/kg DM diets and faeces (Diet × P level, P = 0.047 and < 0.01, respectively as well as PO in the ileal digesta expressed as g/kg DM digesta (Diet × P level, P = 0.04 were affected by diet and P level, which were due to the significant reduction (P < 0.01 by PHY supplementation to the diets with 3.0 g/kg total P. The results evidenced that supplemental phytase improved the APD and PO when chicks was fed 3.0 g/kg total P diet, while lower total P levels may limit exogenous phytase efficacy.

  14. Nickel-Catalyzed C–O Bond-Cleaving Alkylation of Esters: Direct Replacement of the Ester Moiety by Functionalized Alkyl Chains

    KAUST Repository

    Liu, Xiangqian; Jia, Jiaqi; Rueping, Magnus

    2017-01-01

    Two efficient protocols for the nickel-catalyzed aryl–alkyl cross-coupling reactions using esters as coupling components have been established. The methods enable the selective oxidative addition of nickel to acyl C–O and aryl C–O bonds and allow the aryl–alkyl cross-coupling via decarbonylative bond cleavage or through cleavage of a C–O bond with high efficiency and good functional group compatibility. The protocols allow the streamlined, unconventional utilization of widespread ester groups and their precursors, carboxylic acids and phenols, in synthetic organic chemistry.

  15. Nickel-Catalyzed C–O Bond-Cleaving Alkylation of Esters: Direct Replacement of the Ester Moiety by Functionalized Alkyl Chains

    KAUST Repository

    Liu, Xiangqian

    2017-06-07

    Two efficient protocols for the nickel-catalyzed aryl–alkyl cross-coupling reactions using esters as coupling components have been established. The methods enable the selective oxidative addition of nickel to acyl C–O and aryl C–O bonds and allow the aryl–alkyl cross-coupling via decarbonylative bond cleavage or through cleavage of a C–O bond with high efficiency and good functional group compatibility. The protocols allow the streamlined, unconventional utilization of widespread ester groups and their precursors, carboxylic acids and phenols, in synthetic organic chemistry.

  16. Complex formation of technetium with the methyl esters of MAG2 and MAG1

    International Nuclear Information System (INIS)

    Noll, B.; Noll, S.; Grosse, B.; Johannsen, B.; Spies, H.

    1993-01-01

    Mercaptoacetylglycine methyl ester (MAG 2 ester) and mercaptoacetyldiglycine methyl ester (MAG 1 ester) were included to investigate complex formation of SH/amide ligands with technetium. The studies are aimed at finding out how blocking the carboxylic groups influences the complexation reaction, with a view to finding an approach to new lipophilic species. (orig./BBR)

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

    Science.gov (United States)

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

    2011-01-01

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

  18. Synthesis of chiral N-phosphinyl α-imino esters and their application in asymmetric synthesis of α-amino esters by reduction

    OpenAIRE

    Xiong, Yiwen; Mei, Haibo; Wu, Lingmin; Han, Jianlin; Pan, Yi; Li, Guigen

    2014-01-01

    A variety of chiral N-phosphinyl α-imino esters have been synthesized for the first time from ketoesters and phosphinylamide, which were then reduced by L-selectride to give the corresponding N-phosphinyl-protected α-amino esters. The reduction proceeded very well with excellent chemical yields (88–98%) as well as high diastereoselectivities (96:4 to 99:1). Some of these products could be obtained without column chromatography and recrystallization. The chiral phosphinyl auxiliary could be ea...

  19. Antinociceptive esters of N-methylanthranilic acid: Mechanism of action in heat-mediated pain.

    Science.gov (United States)

    Pinheiro, Mariana Martins Gomes; Radulović, Niko S; Miltojević, Ana B; Boylan, Fabio; Dias Fernandes, Patrícia

    2014-03-15

    Recently, we identified a new natural antinociceptive alkaloid ternanthranin, isopropyl N-methylanthranilate (ISOAN), from the plant species Choisya ternata Kunth (Rutaceae). In this work we concentrated on the elucidation of its mechanism of action in comparison with two other esters of this acid (methyl (MAN) and propyl (PAN)). Mice orally pre-treated with ISOAN, MAN or PAN (at 0.3, 1 and 3mg/kg) were less sensitive to chemical or thermal stimuli in different nociception models (formalin-, capsaicin- and glutamate-induced licking response, tail flick and hot plate). All compounds (1 and 3mg/kg) showed significant activity in the peripheral nociception models, as well as a dose-dependent spinal antinociceptive effect in the tail flick model. We observed that glibenclamide was able to reverse the antinociceptive effect of ISOAN in the hot plate model suggesting the involvement of K(+)ATP channels. The antinociceptive effect of MAN and PAN may be related to adrenergic, nitrergic and serotoninergic pathways. In addition, the antinociception of PAN was reverted by naloxone implying that the opioid pathway participates in its activity. The cholinergic and cannabinoid systems were found not be involved in the onset of the antinociceptive effects of any of the esters. In conclusion, isopropyl, methyl and propyl N-methylanthranilates produced significant peripheral and central antinociception at doses lower than that of morphine, the classical opioid analgesic drug, without causing toxicity. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Synthesis of [11C]-labelled methyl esters: transesterification of enol esters versus BF3 etherate catalysed esterification - a comparative study

    International Nuclear Information System (INIS)

    Ackermann, U.; Falzon, C.; Issa, W.; Tochon-Danguy, H.J.; Sachinidis, J.I.; Blanc, P.; White, J.; Scott, A.M.

    2005-01-01

    An important issue in Positron Emission Tomography (PET) is the development of labelling techniques to incorporate positron emitting radionuclides into biologically active compounds. When labelling with 11C, the short 20 minutes half-life of the radionuclide significantly limits the number of synthetic protocols available to the radiochemist. C-l synthons such as [HCJ-methyl iodide (1) or methyl triflate (2) are readily available and are frequently used as alkylating agents for the preparation of radiopharmaceuticals. However, the use of these alkylating agents often makes it necessary to introduce protecting groups in order to prevent labelling at unwanted sites on the molecule. Since the removal of protecting groups is a time-consuming process, a more direct synthesis strategy is desirable. This has prompted us to investigate the esterification of carboxylic acids using [1 lC]-mcthanol and BF3 etherate as Lewis acid catalyst. Our results have demonstrated that the reaction conditions necessary to promote the esterification can cleave functional groups such as ethers. We have therefore shifted our attention towards the irreversible transesterification of enol esters using [HCl-methanol and a tin catalyst as an alternative strategy to [HC]-methyl ester formation. We have prepared a series of 5 aromatic ethoxy vinyl esters bearing various functional groups. The transesterification (radiolabelling) was carried out in DMSO at 150 Degrees C for 7 minutes in the presence of [HQMeOH and 1.3-dichlo-rotetrabutyldistannoxane as catalyst. We have found that the transesterification of enol esters is a mild and efficient labelling method for the formation of [HCl-methyl esters. The reaction proceeds smoothly and leaves functional groups intact. It requires only one synthesis step compared to two steps for the conventional method, and gives a radiochemical yields of 25%

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

    Science.gov (United States)

    Zou, Jinte; Li, Yongmei

    2016-10-01

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

  2. Phosphorus fertilizer and grazing management effects on phosphorus in runoff from dairy pastures.

    Science.gov (United States)

    Dougherty, Warwick J; Nicholls, Paul J; Milham, Paul J; Havilah, Euie J; Lawrie, Roy A

    2008-01-01

    Fertilizer phosphorus (P) and grazing-related factors can influence runoff P concentrations from grazed pastures. To investigate these effects, we monitored the concentrations of P in surface runoff from grazed dairy pasture plots (50 x 25 m) treated with four fertilizer P rates (0, 20, 40, and 80 kg ha(-1) yr(-1)) for 3.5 yr at Camden, New South Wales. Total P concentrations in runoff were high (0.86-11.13 mg L(-1)) even from the control plot (average 1.94 mg L(-1)). Phosphorus fertilizer significantly (P pasture biomass (P dairy pastures should be the maintenance of soil P at or near the agronomic optimum by the use of appropriate rates of P fertilizer.

  3. New Insights on Degumming and Bleaching Process Parameters on The Formation of 3-Monochloropropane-1,2-Diol Esters and Glycidyl Esters in Refined, Bleached, Deodorized Palm Oil.

    Science.gov (United States)

    Sim, Biow Ing; Muhamad, Halimah; Lai, Oi Ming; Abas, Faridah; Yeoh, Chee Beng; Nehdi, Imededdine Arbi; Khor, Yih Phing; Tan, Chin Ping

    2018-04-01

    This paper examines the interactions of degumming and bleaching processes as well as their influences on the formation of 3-monochloropropane-1,2-diol esters (3-MCPDE) and glycidyl esters in refined, bleached and deodorized palm oil by using D-optimal design. Water degumming effectively reduced the 3-MCPDE content up to 50%. Acid activated bleaching earth had a greater effect on 3-MCPDE reduction compared to natural bleaching earth and acid activated bleaching earth with neutral pH, indicating that performance and adsorption capacities of bleaching earth are the predominant factors in the removal of esters, rather than its acidity profile. The combination of high dosage phosphoric acid during degumming with the use of acid activated bleaching earth eliminated almost all glycidyl esters during refining. Besides, the effects of crude palm oil quality was assessed and it was found that the quality of crude palm oil determines the level of formation of 3-MCPDE and glycidyl esters in palm oil during the high temperature deodorization step of physical refining process. Poor quality crude palm oil has strong impact towards 3-MCPDE and glycidyl esters formation due to the intrinsic components present within. The findings are useful to palm oil refining industry in choosing raw materials as an input during the refining process.

  4. Dietary phosphorus requirement of pejerrey fingerlings (Odontesthes bonariensis

    Directory of Open Access Journals (Sweden)

    Cleber Bastos Rocha

    2014-02-01

    Full Text Available To determine the available phosphorus requirement of pejerrey fish, four semi-purified diets were formulated to contain increasing available phosphorus levels (0.90, 2.7, 5.7 and 8.3 g/kg. Each diet was assigned to groups of 10 fish with average weight of 1.26±0.17 g, distributed into a completely randomized design with four treatments and four replications. Fish were fed at a rate of 10% total biomass four times a day for 60 days. The parameters productive performance, body chemical composition and mineral composition of bones and scales were evaluated. The best productive performance of fingerlings was obtained with the diet containing 4.3 g/kg available phosphorus. The average level of 6.3 g/kg available phosphorus promotes better mineralization of bones and scales in pejerrey fish.

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

    Science.gov (United States)

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

    2018-03-01

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

  6. Water Quality Criteria for White Phosphorus

    Science.gov (United States)

    1987-08-01

    the number of eggs produced per adult , Chronic tests using inidges exposed to elemental phosphorus through contaminated sediments were also performed by...hemoglobinemia, hemoglobinuria, hematuria, bilirubinemia, mild (Cases 2 and 3) to severe (Case 1) hypocalcemia , -61- r. ., TABLE 14. SUMMARY OF CASUALTIES...day yellow phosphorus in corn oil for 30 days or less, lost weight. Young adult rats injected with 0.5 mg/kg/day lost less weight than fully mature or

  7. Phosphorus availability and microbial respiration across biomes :  from plantation forest to tundra

    OpenAIRE

    Esberg, Camilla

    2010-01-01

    Phosphorus is the main limiting nutrient for plant growth in large areas of the world and the availability of phosphorus to plants and microbes can be strongly affected by soil properties. Even though the phosphorus cycle has been studied extensively, much remains unknown about the key processes governing phosphorus availability in different environments. In this thesis the complex dynamics of soil phosphorus and its availability were studied by relating various phosphorus fractions and soil ...

  8. Genetics evaluation of phosphorus utilization in tropical cowpea ...

    African Journals Online (AJOL)

    Genetics evaluation of phosphorus utilization in tropical cowpea (Vigna ... that responds negatively to RP, using generation mean analysis of the parents, their ... was observed to be below the critical level, phosphorus uptake in the F1 and the ...

  9. Preparation of esters of gallic acid with higher primary alcohols

    NARCIS (Netherlands)

    Kerk, G.J.M. van der; Verbeek, J.H.; Cleton, J.C.F.

    1951-01-01

    The esters of gallic acid and higher primary alcohols, especially fatty alcohols, have recently gained considerable interest as possible antioxidants for fats. Two independent methods for the preparation of these esters are described. In the first method the hitherto unknown compound galloyl

  10. Bloodcompatibility improvement of titanium oxide film modified by phosphorus ion implantation

    International Nuclear Information System (INIS)

    Yang, P.; Leng, Y.X.; Zhao, A.S.; Zhou, H.F.; Xu, L.X.; Hong, S.; Huang, N.

    2006-01-01

    Our recent investigation suggested that Ti-O thin film could be a newly developed antithrombotic material and its thromboresistance could be related to its physical properties of wide gap semiconductor. In this work, titanium oxide film was modified by phosphorus ion implantation and succeeding vacuum annealing. RBS were used to investigate phosphorus distribution profile. Contact angle test results show that phosphorus-doped titanium oxide film becomes more hydrophilic after higher temperature annealing, while its electric conductivity increases. Antithrombotic property of phosphorus-doped titanium oxide thin films was examined by clotting time and platelet adhesion tests. The results suggest that phosphorus doping is an effective way to improve the bloodcompatibility of titanium oxide film, and it is related to the changes of electron structure and surface properties caused by phosphorus doping

  11. Baker's yeast: production of D- and L-3-hydroxy esters

    DEFF Research Database (Denmark)

    Dahl, Allan Carsten; Madsen, Jørgen Øgaard

    1998-01-01

    harvested while growing. In contrast, the stereoselectivity was shifted towards L-hydroxy esters when the oxo esters were added slowly to ordinary baker's yeast supplied with gluconolactone as co-substrate. The reduction rate with gluconolactone was increased by active aeration. Ethyl L-(S)-3......Baker's yeast grown under oxygen limited conditions and used in the reduction of 3-oxo esters results in a shift of the stereoselectivity of the yeast towards D-hydroxy esters as compared with ordinary baker's yeast. The highest degree of stereoselectivity was obtained with growing yeast or yeast......-hydroxybutanoate was afforded in >99% ee. Both enantiomers of ethyl 3-hydroxypentanoate, D-(R) in 96% ee and L-(S) in 93% ee, and of ethyl 4-chloro-3-hydroxybutanoate, D-(S) in 98% ee and L-(R) in 94% ee, were obtained. The results demonstrate that the stereoselectivity of baker's yeast can be controlled...

  12. Fractions and Distribution of Phosphorus in Sediments of the Yarlung Zangbo River Basin

    Science.gov (United States)

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

    2017-12-01

    The Yarlung Zangbo River is one of the highest rivers in the world. The ecological environment of the river basin has its specificity. It locates in the remote area of China, and the ecological environment is very fragile. The fundamental data of phosphorus content in sediments of the Yarlung Zangbo River Basin are very scarce. In order to clarify the distribution law of phosphorus in the sediments of this area and provide the fundamental data for the study of phosphorus transport in the Yarlung Zangbo River, the authors collected the sediment samples from the mainstream and its tributaries in the research area. Their particle size distributions, specific surface areas, contents of total phosphorus, organic phosphorus and different forms of inorganic phosphorus were analyzed. Then, the fractions and spatial distribution of these forms phosphorus were studied. The results showed that the fractions and distribution characteristics of phosphorus in each form are significant different in the sediments of the Yarlung Zangbo River. The phosphorus contents in the soil erosion deposits and river bed sediment samples are also different. The phosphorus content in sediment is significantly correlated with the sediment characteristics. Keywords: the Yarlung Zangbo River; sediments; fractions of phosphorus; distribution characteristics

  13. The release of dissolved phosphorus from lake sediments

    NARCIS (Netherlands)

    Boers, P.C.M.

    1991-01-01

    Chapter 1. Introduction: Eutrophication is one of the world's major water quality problems. Attempts to alleviate eutrophication of lakes have involved the control of phosphorus loadings. In such cases, an internal loading of phosphorus from the sediments may

  14. Synthesis of novel naphthoquinone aliphatic amides and esters and their anticancer evaluation.

    Science.gov (United States)

    Kongkathip, Boonsong; Akkarasamiyo, Sunisa; Hasitapan, Komkrit; Sittikul, Pichamon; Boonyalai, Nonlawat; Kongkathip, Ngampong

    2013-02-01

    Fourteen new naphthoquinone aliphatic amides and seventeen naphthoquinone aliphatic esters were synthesized in nine to ten steps from 1-hydroxy-2-naphthoic acid with 9-25% overall yield for the amides, and 16-21% overall yield for the esters. The key step of the amide synthesis is a coupling reaction between amine and various aliphatic acids using 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMTMM) as a coupling agent while for the ester synthesis, DCC/DMAP or CDI was used as the coupling reagent between aliphatic acids and naphthoquinone alcohol. Both naphthoquinone amides and esters were evaluated for their anticancer activity against KB cells. It was found that naphthoquinone aliphatic amides showed stronger anticancer activity than those of the esters when the chains are longer than 7-carbon atoms. The optimum chain of amides is expected to be 16-carbon atoms. In addition, naphthoquinone aliphatic esters with α-methyl on the ester moiety possessed much stronger anticancer activity than the straight chains. Decatenation assay revealed that naphthoquinone amide with 16-carbon atoms chain at 15 μM and 20 μM can completely inhibit hTopoIIα activity while at 10 μM the enzyme activity was moderately inhibited. Molecular docking result also showed the same trend as the cytotoxicity and decatenation assay. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  15. Synthesis of chiral N-phosphinyl α-imino esters and their application in asymmetric synthesis of α-amino esters by reduction.

    Science.gov (United States)

    Xiong, Yiwen; Mei, Haibo; Wu, Lingmin; Han, Jianlin; Pan, Yi; Li, Guigen

    2014-01-01

    A variety of chiral N-phosphinyl α-imino esters have been synthesized for the first time from ketoesters and phosphinylamide, which were then reduced by L-selectride to give the corresponding N-phosphinyl-protected α-amino esters. The reduction proceeded very well with excellent chemical yields (88-98%) as well as high diastereoselectivities (96:4 to 99:1). Some of these products could be obtained without column chromatography and recrystallization. The chiral phosphinyl auxiliary could be easily cleaved under acidic conditions.

  16. Phosphorus Uptake and Partitioning in Maize as Affected by Tillage ...

    African Journals Online (AJOL)

    Higher phosphorus concentrations were found in the ears than in the shoots and leaves at physiological maturity. Tillage x phospho-rus interactions influenced phosphorus partitioning in the ears and the leaves on the Dystric Cam-bisol but not on the Ferric Acrisol. PUE in the plant parts were significantly higher under ...

  17. Sugar ester surfactants: enzymatic synthesis and applications in food industry.

    Science.gov (United States)

    Neta, Nair S; Teixeira, José A; Rodrigues, Lígia R

    2015-01-01

    Sugar esters are non-ionic surfactants that can be synthesized in a single enzymatic reaction step using lipases. The stability and efficiency of lipases under unusual conditions and using non-conventional media can be significantly improved through immobilization and protein engineering. Also, the development of de novo enzymes has seen a significant increase lately under the scope of the new field of synthetic biology. Depending on the esterification degree and the nature of fatty acid and/or sugar, a range of sugar esters can be synthesized. Due to their surface activity and emulsifying capacity, sugar esters are promising for applications in food industry.

  18. Lead immobilization and phosphorus availability in phosphate-amended, mine-contaminated soils.

    Science.gov (United States)

    Osborne, Lydia R; Baker, Leslie L; Strawn, Daniel G

    2015-01-01

    Over a century of mining activities in the Coeur d'Alene mining district in Idaho have contaminated soils of the downstream basin with lead, arsenic, zinc, and cadmium. Elevated soil-Pb levels are a significant hazard to the health of humans and wildlife in the region. One in situ treatment approach for remediating Pb-contaminated soils is application of phosphorus to promote the formation of lead phosphate minerals that have low solubility. However, this remediation strategy may result in excess P runoff to surface waters, which can lead to eutrophication, particularly when used in riparian areas. Research presented in this paper describes experiments in which monopotassium phosphate (KHPO) solution was applied to two Pb-contaminated soils from the Coeur d'Alene River valley to determine how P loading rates affect both Pb immobilization and P mobility and to determine if an optimal P amendment rate can be predicted. Toxicity characteristic leaching procedure extractions were used to assess changes in Pb availability for uptake by an organism or mobilization through the soil, and Bray extractions were used to assess P availability for leaching out of the soil system. For the two soils tested, increasing phosphate amendment caused decreasing Pb extractability. Phosphorus amendment rates above approximately 70 mg kg, however, did not provide any additional Pb immobilization. Phosphorus availability increased with increasing phosphate application rate. An empirical relationship is presented that predicts extractable Pb as a function of extractable P. This relationship allows for prediction of the amount of Pb that can be immobilized at specified P leaching amounts, such as regulatory levels that have been established to minimize risks for surface water degradation. Results suggest that phosphate can be used to immobilize Pb in contaminated wetland or riparian areas without posing risks of P loading to surface waters. Copyright © by the American Society of Agronomy

  19. Black Phosphorus: Critical Review and Potential for Water Splitting Photocatalyst

    Directory of Open Access Journals (Sweden)

    Tae Hyung Lee

    2016-10-01

    Full Text Available A century after its first synthesis in 1914, black phosphorus has been attracting significant attention as a promising two-dimensional material in recent years due to its unique properties. Nowadays, with the development of its exfoliation method, there are extensive applications of black phosphorus in transistors, batteries and optoelectronics. Though, because of its hardship in mass production and stability problems, the potential of the black phosphorus in various fields is left unexplored. Here, we provide a comprehensive review of crystal structure, electronic, optical properties and synthesis of black phosphorus. Recent research works about the applications of black phosphorus is summarized. Among them, the possibility of black phosphorous as a solar water splitting photocatalyst is mainly discussed and the feasible novel structure of photocatalysts based on black phosphorous is proposed.

  20. Global Fertilizer and Manure, Version 1: Phosphorus Fertilizer Application

    Data.gov (United States)

    National Aeronautics and Space Administration — The Phosphorus Fertilizer Application dataset of the Global Fertilizer and Manure, Version 1 Data Collection represents the amount of phosphorus fertilizer nutrients...

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

    Science.gov (United States)

    Uribarri, Jaime; Calvo, Mona S

    2013-09-01

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

  2. Esters of 3-chloro-1,2-propanediol (3-MCPD) in vegetable oils: significance in the formation of 3-MCPD.

    Science.gov (United States)

    Seefelder, W; Varga, N; Studer, A; Williamson, G; Scanlan, F P; Stadler, R H

    2008-04-01

    3-Mono-chloropropane-1,2-diol (3-MCPD) is a contaminant that occurs in food in its free (diol) form as well as in an esterified (with fatty acids) form. Using a simple intestinal model, it was demonstrated that 3-MCPD monoesters and 3-MCPD diesters are accepted by intestinal lipase as substrates in vitro. Under the chosen conditions, the yield of 3-MCPD from a 3-MCPD monoester was greater than 95% in approximately 1 min. Release from the diesters was slower, reaching about 45, 65 and 95% of 3-MCPD after 1, 5 and 90 min of incubation, respectively. However, in human, the hydrolysis of 3-MCPD esters is unlikely to release 100% as 3-MCPD, as triglycerides and phospholipids are hydrolysed in the intestine liberating 2-monoglycerides. Assuming a similar metabolism for 3-MCPD esters as that known for acylglycerols in humans in vivo, the de-esterification in positions 1 and 3 would thus be favoured by pancreatic lipases. Therefore, 3-MCPD, and 3-MCPD-2 monoesters would be released, respectively, from the 1-/3-monoesters, and the diesters potentially present in food. Hence, information on the exact amounts of the partial fatty acid chloroesters, i.e. 3-MCPD mono- and diesters, is important to assess the contribution of foods to the bioavailability of 3-MCPD. Therefore, a rapid method for the determination of the ratio of 3-MCPD monoesters to diesters in fats and oils was developed using gas chromatography-mass spectrometry (GC-MS) and isotopically labelled 3-MCPD esters as internal standards. The analysis of 11 different samples of fat mixes typically employed in food manufacturing demonstrated that a maximum of about 15% of the total amount of 3-MCPD bound in esters is present in the monoesterified form. The potentially slower release of 3-MCPD from 3-MCPD diesters, and the mono- to diesters ratio suggest that 3-MCPD esters may in fact contribute only marginally to the overall dietary exposure to 3-MCPD. Further work on the bioavailability, metabolism and possible

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

    Science.gov (United States)

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

    2017-10-01

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

  4. Novel Synthesis of Phytosterol Ester from Soybean Sterol and Acetic Anhydride.

    Science.gov (United States)

    Yang, Fuming; Oyeyinka, Samson A; Ma, Ying

    2016-07-01

    Phytosterols are important bioactive compounds which have several health benefits including reduction of serum cholesterol and preventing cardiovascular diseases. The most widely used method in the synthesis of its ester analogous form is the use of catalysts and solvents. These methods have been found to present some safety and health concern. In this paper, an alternative method of synthesizing phytosterol ester from soybean sterol and acetic anhydride was investigated. Process parameters such as mole ratio, temperature and time were optimized. The structure and physicochemical properties of phytosterol acetic ester were analyzed. By the use of gas chromatography, the mole ratio of soybean sterol and acetic anhydride needed for optimum esterification rate of 99.4% was 1:1 at 135 °C for 1.5 h. FTIR spectra confirmed the formation of phytosterol ester with strong absorption peaks at 1732 and 1250 cm(-1) , which corresponds to the stretching vibration of C=O and C-O-C, respectively. These peaks could be attributed to the formation of ester links which resulted from the reaction between the hydroxyl group of soybean sterol and the carbonyl group of acetic anhydride. This paper provides a better alternative to the synthesis of phytosterol ester without catalyst and solvent residues, which may have potential application in the food, health-care food, and pharmaceutical industries. © 2016 Institute of Food Technologists®

  5. Effect of phosphorus on hot ductility of high purity iron

    International Nuclear Information System (INIS)

    Abiko, K.; Liu, C.M.; Ichikawa, M..; Suenaga, H.; Tanino, M.

    1995-01-01

    Tensile tests on high purity Fe-P alloys with 0, 0.05 and 0.1 mass%P were carried out at temperatures between 300 K and 1073 K to clarify the intrinsic effect of phosphorus on the mechanical properties of iron at elevated temperatures. Microstructures of as-quenched, interrupted and ruptured specimens were observed. Experimental results show that the addition of phosphorus causes a remarkable increase in proof stress of high purity iron at 300 K, but the increase in proof stress by phosphorus decreases with increasing test temperature. The strengthening effect of phosphorus reduces to zero at 1073 K. High purity iron and Fe-P alloys rupture at almost 100% reduction in area at the whole test temperatures. However, Fe-P alloys show much larger elongation at test temperatures above 773 K than high purity iron. The increased elongation of high purity iron by addition of phosphorus was shown to be related to the effect of phosphorus on dynamic recovery and recrystallization of iron as its intrinsic effect. (orig.)

  6. Physicochemical properties of mixed phosphorus halides

    International Nuclear Information System (INIS)

    Sladkov, I.B.; Tugarinova, N.S.

    1996-01-01

    Certain physicochemical properties (thermodynamic characteristics at boiling point, critical constants, density of liquid on the saturation line) of mixed phosphorus halides (PI 3 , PI 2 F, PIF 2 , PI 2 Cl, PICl 2 , PI 1 Br, PIBr 2 , PIClF, PIBrCl, etc.) are determined by means of approximate methods. Reliability of the results obtained is confirmed by comparison of calculated and experimental data for phosphorus compounds of the same type. 7 refs., 3 figs., 4 tabs

  7. Ester-free Thiol-X Resins: New Materials with Enhanced Mechanical Behavior and Solvent Resistance

    OpenAIRE

    Podgórski, Maciej; Becka, Eftalda; Chatani, Shunsuke; Claudino, Mauro; Bowman, Christopher N.

    2015-01-01

    A series of thiol-Michael and radical thiol-ene network polymers were successfully prepared from ester-free as well as ester-containing monomer formulations. Polymerization reaction rates, dynamic mechanical analysis, and solvent resistance experiments were performed and compared between compositions with varied ester loading. The incorporation of ester-free alkyl thiol, vinyl sulfone and allylic monomers significantly improved the mechanical properties when compared with commercial, mercapto...

  8. Encapsulating fatty acid esters of bioactive compounds in starch

    Science.gov (United States)

    Lay Ma, Ursula Vanesa

    Interest in the use of many bioactive compounds in foods is growing in large part because of the apparent health benefits of these molecules. However, many of these compounds can be easily degraded during processing, storage, or their passage through the gastrointestinal tract before reaching the target site. In addition, they can be bitter, acrid, or astringent, which may negatively affect the sensory properties of the product. Encapsulation of these molecules may increase their stability during processing, storage, and in the gastrointestinal tract, while providing controlled release properties. The ability of amylose to form inclusion complexes and spherulites while entrapping certain compounds has been suggested as a potential method for encapsulation of certain molecules. However, complex formation and spherulitic crystallization are greatly affected by the type of inclusion molecules, type of starch, and processing conditions. The objectives of the present investigation were to: (a) study the effect of amylose, amylopectin, and intermediate material on spherulite formation and its microstructure; (b) investigate the formation of amylose and high amylose starch inclusion complexes with ascorbyl palmitate, retinyl palmitate, and phytosterol esters; (c) evaluate the ability of spherulites to form in the presence of fatty acid esters and to entrap ascorbyl palmitate, retinyl palmitate, and phytosterol esters; and (d) evaluate the effect of processing conditions on spherulite formation and fatty acid ester entrapment. Higher ratios of linear to branched molecules resulted in the formation of more and rounder spherulites with higher heat stability. In addition to the presence of branches, it appears that spherulitic crystallization is also affected by other factors, such as degree of branching, chain length, and chain length distribution. Amylose and Hylon VII starch formed inclusion complexes with fatty acid esters of ascorbic acid, retinol, or phytosterols

  9. Unsaturated Fatty Acid Esters Metathesis Catalyzed by Silica Supported WMe5

    KAUST Repository

    Riache, Nassima; Callens, Emmanuel; Talbi, Karima; Basset, Jean-Marie

    2015-01-01

    Metathesis of unsaturated fatty acid esters (FAEs) by silica supported multifunctional W-based catalyst is disclosed. This transformation represents a novel route towards unsaturated di-esters. Especially, the self-metathesis of ethyl undecylenate

  10. Synthesis of oleyl oleate wax esters in Arabidopsis thaliana and Camelina sativa seed oil.

    Science.gov (United States)

    Iven, Tim; Hornung, Ellen; Heilmann, Mareike; Feussner, Ivo

    2016-01-01

    Seed oil composed of wax esters with long-chain monoenoic acyl moieties represents a high-value commodity for industry. Such plant-derived sperm oil-like liquid wax esters are biodegradable and can have excellent properties for lubrication. In addition, wax ester oil may represent a superior substrate for biodiesel production. In this study, we demonstrate that the low-input oil seed crop Camelina sativa can serve as a biotechnological platform for environmentally benign wax ester production. Two biosynthetic steps catalysed by a fatty alcohol-forming acyl-CoA reductase (FAR) and a wax ester synthase (WS) are sufficient to achieve wax ester accumulation from acyl-CoA substrates. To produce plant-derived sperm oil-like liquid wax esters, the WS from Mus musculus (MmWS) or Simmondsia chinensis (ScWS) were expressed in combination with the FAR from Mus musculus (MmFAR1) or Marinobacter aquaeolei (MaFAR) in seeds of Arabidopsis thaliana and Camelina sativa. The three analysed enzyme combinations Oleo3:mCherry:MmFAR1∆c/Oleo3:EYFP:MmWS, Oleo3:mCherry:MmFAR1∆c/ScWS and MaFAR/ScWS showed differences in the wax ester molecular species profiles and overall biosynthetic performance. By expressing MaFAR/ScWS in Arabidopsis or Camelina up to 59% or 21% of the seed oil TAGs were replaced by wax esters, respectively. This combination also yielded wax ester molecular species with highest content of monounsaturated acyl moieties. Expression of the enzyme combinations in the Arabidopsis fae1 fad2 mutant background high in oleic acid resulted in wax ester accumulation enriched in oleyl oleate (18:1/18:1 > 60%), suggesting that similar values may be obtained with a Camelina high oleic acid line. © 2015 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  11. Conformational states of N-acylalanine dithio esters: correlation of resonance Raman spectra with structures

    International Nuclear Information System (INIS)

    Lee, H.; Angus, R.H.; Storer, A.C.; Varughese, K.I.; Carey, P.R.

    1988-01-01

    The conformational states of N-acylalanine dithio esters, involving rotational isomers about the RC(=O)NH-CH(CH 3 ) and NHCH(CH 3 )-C(=S) bonds, are defined and compared to those of N-acylglycine dithio esters. The structure of N-(p-nitrobenzoyl)-DL-alanine ethyl dithio ester has been determined by X-ray crystallographic analysis; it is a B-type conformer with the amide N atom cis to the thiol sulfur. Raman and resonance Raman (RR) measurements on this compound and for the B conformers of solid N-benzoyl-DL-alanine ethyl dithio ester and N-(β-phenylpropionyl)-DL-alanine ethyl dithio ester and its NHCH(CD 3 )C(=S) and NHCH(CH 3 ) 13 C(=S) analogues are used to set up a library of RR data for alanine-based dithio esters in a B-conformer state. RR data for this solid material in its isotopically unsubstituted and CH(C-D 3 )C(=S) and CH(CH 3 ) 13 C(=S) forms provide information on the RR signatures of alanine dithio esters in A-like conformations. RR spectra are compared for the solid compounds, for N-(p-nitrobenzoyl)-DL-alanine, N-(β-phenylpropionyl)-DL-alanine, and (methyloxycarbonyl)-L-phenylalanyl-DL-alanine ethyl dithio ester, and for several 13 C=S- and CD 3 -substituted analogues in CCl 4 or aqueous solutions. The RR data demonstrate that the alanine-based dithio esters take up A, B, and C 5 conformations in solution. The RR spectra of these conformers are clearly distinguishable from those for the same conformers of N-acylglycine dithio esters. However, the crystallographic and spectroscopic results show that the results show that the conformational properties of N-acylglycine and N-acylalanine dithio esters are very similar

  12. Synthesis and characterization of ester and amide derivatives of titanium(IV) carboxymethylphosphonate

    International Nuclear Information System (INIS)

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

    2013-01-01

    A set of layered ester and amide derivatives of titanium(IV) carboxymethylphosphonate was prepared by solvothermal treatment of amorphous titanium(IV) carboxymethylphosphonate with corresponding 1-alkanols, 1,ω-alkanediols, 1-aminoalkanes, 1,ω-diaminoalkanes and 1,ω-amino alcohols and characterized by powder X-ray diffraction, IR spectroscopy and thermogravimetric analysis. Whereas alkyl chains with one functional group form bilayers tilted to the layers, 1,ω-diaminoalkanes and most of 1,ω-alkanediols form bridges connecting the adjacent layers. In the case of amino alcohols, the alkyl chains form bilayer and either hydroxyl or amino group is used for bonding. This simple method for the synthesis of ester and amide derivatives does not require preparation of acid chloride derivative as a precursor or pre-intercalation with alkylamines and can be used also for the preparation of ester and amide derivatives of titanium carboxyethylphosphonate and zirconium carboxymethylphosphonate. - Graphical abstract: Ester and amide derivatives of layered titanium carboxymethylphosphonate were prepared by solvothermal treatment of amorphous solid with alkanol or alkylamine. - Highlights: • Ester and amide derivatives of titanium carboxymethylphosphonate. • Solvothermal treatment of amorphous solid with alkanol or alkylamine. • Ester and amide formation confirmed by IR spectroscopy

  13. Long-Acting Diclofenac Ester Prodrugs for Joint Injection

    DEFF Research Database (Denmark)

    Mertz, Nina; Larsen, Susan Weng; Kristensen, Jesper

    2016-01-01

    A prodrug approach for local and sustained diclofenac action after injection into joints based on ester prodrugs having a pH-dependent solubility is presented. Inherent ester prodrug properties influencing the duration of action include their pH-dependent solubility and charge state, as well...... as susceptibility to undergo esterase facilitated hydrolysis. In this study, physicochemical properties and pH rate profiles of 3 diclofenac ester prodrugs differing with respect to the spacer carbon chain length between the drug and the imidazole-based promoiety were determined and a rate equation for prodrug...... degradation in aqueous solution in the pH range 1-10 was derived. In the pH range 6-10, the prodrugs were subject to parallel degradation to yield diclofenac and an indolinone derivative. The prodrug degradation was found to be about 6-fold faster in 80% (vol/vol) human plasma as compared to 80% (vol...

  14. Boric Ester-Type Molten Salt via Dehydrocoupling Reaction

    Directory of Open Access Journals (Sweden)

    Noriyoshi Matsumi

    2014-11-01

    Full Text Available Novel boric ester-type molten salt was prepared using 1-(2-hydroxyethyl-3-methylimidazolium chloride as a key starting material. After an ion exchange reaction of 1-(2-hydroxyethyl-3-methylimidazolium chloride with lithium (bis-(trifluoromethanesulfonyl imide (LiNTf2, the resulting 1-(2-hydroxyethyl-3-methylimidazolium NTf2 was reacted with 9-borabicyclo[3.3.1]nonane (9-BBN to give the desired boric ester-type molten salt in a moderate yield. The structure of the boric ester-type molten salt was supported by 1H-, 13C-, 11B- and 19F-NMR spectra. In the presence of two different kinds of lithium salts, the matrices showed an ionic conductivity in the range of 1.1 × 10−4–1.6 × 10−5 S cm−1 at 51 °C. This was higher than other organoboron molten salts ever reported.

  15. Saliva-catalyzed hydrolysis of a ketobemidone ester prodrug

    DEFF Research Database (Denmark)

    Hansen, L.B.; Christrup, Lona Louring; Bundgaard, H.

    1992-01-01

    Saliva enzyme-catalysed hydrolysis of ester prodrugs or drugs containing sensitive ester groups may be a limiting factor for the buccal absorption of such compounds. Using the isopropyl carbonate ester of ketobemidone as a model substance of a hydrolysis-sensitive prodrug the esterase activity...... of human saliva has been characterized as a function of various factors. The esterase activity was found to decrease rapidly upon storage of the saliva at 37°C. The activity increased with increasing pH in the range 4.5-7.4 and with increasing salivation flow rate up to a rate of 0.9 ml min. Under resting...... conditions, the flow rate was about 0.2 ml min which implied a greatly decreased esterase activity. The activity was highest after fasting and decreased after intake of a meal. The intraindividual variation in the saliva esterase activity was small whereas a larger interindividual variation was found....

  16. [Development of the determination methods of fatty acid esters of chloropropanediols in fat-rich foods].

    Science.gov (United States)

    Yan, Xiaobo; Wu, Shaoming; Li, Nan; Lü, Huadong; Fu, Wusheng

    2013-02-01

    Fatty acid esters of chloropropanediols are a kinds of newly emerged food contaminants, especially 3-monochloropropane-1,2-diol (3-MCPD) esters that have been detected in many foodstuffs such as infant formula and edible oils at relatively high levels. Based on the Tolerable Dose Intake (TDI) of 3-MCPD, the intake of 3-MCPD from 3-MCPD esters may cause the health risk to human beings. The researches for the analysis of 3-MCPD esters have been carried out in some institutes abroad, but there were only a few in China. This paper reviews the methods for the determination of 3-MCPD esters in fat-rich foods, including the extraction, hydrolysis, the derivatization of 3-MCPD esters, the total amount of 3-MCPD esters and the amounts of monoesters and diesters of 3-MCPD.

  17. Further developments and field deployment of phosphorus functionalized polymeric scale inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Todd, Malcolm J.; Thornton, Alex R.; Wylde, Jonathan J.; Strachan, Catherine J.; Moir, Gordon [Clariant Oil Services, Muttenz (Switzerland); Goulding, John [John Goulding Consultancy, York (United Kingdom)

    2012-07-01

    As the oil and gas industry strives to replace ageing, environmentally undesirable scale inhibitors there is an ever increasing use of polymeric inhibitors. The incorporation of phosphorous functionality into a polymer backbone has been shown to improve inhibition efficiency, enhance adsorption characteristics and allow the polymer concentration to be analyzed by elemental phosphorus. It is known that some phosphorus tagged polymers can be problematic to analyze in oil field brines as they typically have a low phosphorus content which is difficult to determine from the background. The development of novel phosphorus functionalized polymeric scale inhibitors was previously described (IBP3530-10). This paper follows the development of the inhibitor class. Utilizing extensive laboratory testing the interactive nature of the scale inhibitors and reservoir lithology was studied. These novel phosphorus functionalized inhibitors were compared to a number of other available scale inhibitors. The incorporation of phosphorus functionality into polymeric inhibitors can be expensive utilizing traditional methods as the phosphorus containing monomers are the financially limiting factor. These are typically vinyl phosphonic acid (VPA), or vinyl diphosphonic acid (VDPA). The novel phosphorus functionalized monomers utilized herein are simpler to manufacture allowing higher phosphorus content within the polymer backbone. The addition of phosphorus into a polymer backbone has previously been known to exacerbate analysis issues in some commercially available scale inhibitors. This is due to incomplete polymerization reactions leaving free and/or inorganic phosphorus containing moieties which can interfere with the analysis, or low levels of phosphorus within end-capped polymers can make it difficult to determine the active concentration accurately within field brines which contain many impuritie. Polymeric inhibitors are known to contain a range of molecular weights with varying

  18. Triazole–Au(I complex as chemoselective catalyst in promoting propargyl ester rearrangements

    Directory of Open Access Journals (Sweden)

    Dawei Wang

    2011-07-01

    Full Text Available Triazole–Au (TA–Au catalysts were employed in several transformations involving propargyl ester rearrangement. Good chemoselectivity was observed, which allowed the effective activation of the alkyne without affecting the reactivity of the allene ester intermediates. These results led to the investigation of the preparation of allene ester intermediates with TA–Au catalysts under anhydrous conditions. As expected, the desired 3,3-rearrangement products were obtained in excellent yields (generally >90% yields with 1% loading. Besides the typical ester migrating groups, carbonates and carbamates were also found to be suitable for this transformation, which provided a highly efficient, practical method for the preparation of substituted allenes.

  19. PROCESS FOR HYDROGENOLYSIS OF ALPHA-HYDROXY ESTERS OR ACIDS USING A HETEROGENEOUS CATALYST

    DEFF Research Database (Denmark)

    2017-01-01

    The present invention relates to a method for hydrogenolysis of alpha-hydroxy esters or acids, comprising reacting the alpha-hydroxy ester or acid in the presence of a heterogeneous catalyst. The present invention also relates to a method for producing propionic acid ester, and the use of any...

  20. Ester-free Thiol-X Resins: New Materials with Enhanced Mechanical Behavior and Solvent Resistance.

    Science.gov (United States)

    Podgórski, Maciej; Becka, Eftalda; Chatani, Shunsuke; Claudino, Mauro; Bowman, Christopher N

    A series of thiol-Michael and radical thiol-ene network polymers were successfully prepared from ester-free as well as ester-containing monomer formulations. Polymerization reaction rates, dynamic mechanical analysis, and solvent resistance experiments were performed and compared between compositions with varied ester loading. The incorporation of ester-free alkyl thiol, vinyl sulfone and allylic monomers significantly improved the mechanical properties when compared with commercial, mercaptopropionate-based thiol-ene or thiol-Michael networks. For polymers with no hydrolytically degradable esters, glass transition temperatures (T g 's) as high as 100 °C were achieved. Importantly, solvent resistance tests demonstrated enhanced stability of ester-free formulations over PETMP-based polymers, especially in concentrated basic solutions. Kinetic analysis showed that glassy step-growth polymers are readily formed at ambient conditions with conversions reaching 80% and higher.

  1. Ethylene: a regulator of root architectural responses to soil phosphorus availability

    NARCIS (Netherlands)

    Borch, K.; Bouma, T.J.; Lynch, J.P.; Brown, K.M.

    1999-01-01

    The involvement of ethylene in root architectural responses to phosphorus availability was investigated in common bean (Phaseolus vulgaris L,) plants grown with sufficient and deficient phosphorus. Although phosphorus deficiency reduced root mass and lateral root number, main root length was

  2. Synthesis of chiral N-phosphinyl α-imino esters and their application in asymmetric synthesis of α-amino esters by reduction

    Directory of Open Access Journals (Sweden)

    Yiwen Xiong

    2014-03-01

    Full Text Available A variety of chiral N-phosphinyl α-imino esters have been synthesized for the first time from ketoesters and phosphinylamide, which were then reduced by L-selectride to give the corresponding N-phosphinyl-protected α-amino esters. The reduction proceeded very well with excellent chemical yields (88–98% as well as high diastereoselectivities (96:4 to 99:1. Some of these products could be obtained without column chromatography and recrystallization. The chiral phosphinyl auxiliary could be easily cleaved under acidic conditions.

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

    Science.gov (United States)

    Domagalski, Joseph L.; Johnson, Henry

    2012-01-01

    Phosphorus is a highly reactive element that is essential for life and forms a variety of compounds in terrestrial and aquatic ecosystems. In water, phosphorus may be present as the orthophosphate ion (PO43-) and is also present in all life forms as an essential component of cellular material. In natural ecosystems, phosphorus is derived from the erosion of rocks and is conserved for plant growth as it is returned to the soil through animal waste and the decomposition of plant and animal tissue; but in agricultural systems, a portion of the phosphorus is removed with each harvest, especially since phosphorus is concentrated in the seeds and fruit. Phosphorus is added to soil by using chemical fertilizers, manure, and composted materials. Agricultural use of chemical phosphorus fertilizer, in the United States, in 2008 was 4,247,000 tons, which is an increase of 25 percent since 1964 (http://www.ers.usda.gov/Data/FertilizerUse/). Widely grown corn, soybeans, and wheat use the greatest amount of phosphorus fertilizer among agricultural crops.

  4. Effect of Sucrose Esters on the Physicochemical Properties of Wheat ...

    African Journals Online (AJOL)

    HP

    Purpose: To investigate the effect of sucrose esters on the physicochemical properties of wheat starch. Methods: Sucrose ester was mixed with wheat starch extracted from normal soft wheat cultivars and heated. Change in starch properties arising from the interaction between were assessed for starch blue value, viscosity ...

  5. Simultaneous nitrogen and phosphorus removal in the sulfur cycle-associated Enhanced Biological Phosphorus Removal (EBPR) process.

    Science.gov (United States)

    Wu, Di; Ekama, George A; Wang, Hai-Guang; Wei, Li; Lu, Hui; Chui, Ho-Kwong; Liu, Wen-Tso; Brdjanovic, Damir; van Loosdrecht, Mark C M; Chen, Guang-Hao

    2014-02-01

    Hong Kong has practiced seawater toilet flushing since 1958, saving 750,000 m(3) of freshwater every day. A high sulfate-to-COD ratio (>1.25 mg SO4(2-)/mg COD) in the saline sewage resulting from this practice has enabled us to develop the Sulfate reduction, Autotrophic denitrification and Nitrification Integrated (SANI(®)) process with minimal sludge production and oxygen demand. Recently, the SANI(®) process has been expanded to include Enhanced Biological Phosphorus Removal (EBPR) in an alternating anaerobic/limited-oxygen (LOS-EBPR) aerobic sequencing batch reactor (SBR). This paper presents further development - an anaerobic/anoxic denitrifying sulfur cycle-associated EBPR, named as DS-EBPR, bioprocess in an alternating anaerobic/anoxic SBR for simultaneous removal of organics, nitrogen and phosphorus. The 211 day SBR operation confirmed the sulfur cycle-associated biological phosphorus uptake utilizing nitrate as electron acceptor. This new bioprocess cannot only reduce operation time but also enhance volumetric loading of SBR compared with the LOS-EBPR. The DS-EBPR process performed well at high temperatures of 30 °C and a high salinity of 20% seawater. A synergistic relationship may exist between sulfur cycle and biological phosphorus removal as the optimal ratio of P-release to SO4(2-)-reduction is close to 1.0 mg P/mg S. There were no conventional PAOs in the sludge. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Regulation of phosphorus uptake and utilization: transitioning from current knowledge to practical strategies.

    Science.gov (United States)

    Hasan, Md Mahmudul; Hasan, Md Mainul; Teixeira da Silva, Jaime A; Li, Xuexian

    2016-01-01

    Phosphorus is a poorly bioavailable macronutrient that is essential for crop growth and yield. Overuse of phosphorus fertilizers results in low phosphorus use efficiency (PUE), has serious environmental consequences and accelerates the depletion of phosphorus mineral reserves. It has become extremely challenging to improve PUE while preserving global food supplies and maintaining environmental sustainability. Molecular and genetic analyses have revealed the primary mechanisms of phosphorus uptake and utilization and their relationships to phosphorus transporters, regulators, root architecture, metabolic adaptations, quantitative trait loci, hormonal signaling and microRNA. The ability to improve PUE requires a transition from this knowledge of molecular mechanisms and plant architecture to practical strategies. These could include: i) the use of arbuscular mycorrhizal fungal symbioses for efficient phosphorus mining and uptake; ii) intercropping with suitable crop species to achieve phosphorus activation and mobilization in the soil; and iii) tissue-specific overexpression of homologous genes with advantageous agronomic properties for higher PUE along with breeding for phosphorus-efficient varieties and introgression of key quantitative trait loci. More effort is required to further dissect the mechanisms controlling phosphorus uptake and utilization within plants and provide new insight into the means to efficiently improve PUE.

  7. Determination of phosphorus in gold or silver brazing alloys

    International Nuclear Information System (INIS)

    Antepenko, R.J.

    1976-01-01

    A spectrophotometric method has been devised for measuring microgram levels of phosphorus in brazing alloys of gold or silver alloys is normally measured by solid mass spectrometry, but the high nickel concentration produces a double ionized nickel spectral interference. The described procedures is based upon the formation of molybdovandophosphoric acid when a molybdate solution is added to an acidic solution containing orthophosphate and vanadate ions. The optimum acidity for forming the yellow colored product is 0.5 N hydrochloric acid. The working concentration range is from 0.1 to 1 ppm phosphorus using 100-mm cells and measuring the absorbance at 460 nm. The sample preparation procedure employs aqua regia to dissolve the alloy oxidize the phosphorus to orthophosphate. Cation-exchange chromatography is used to remove nickel ions and anion-exchange and chromatography to remove gold ions as the chloride complex. Excellent recoveries are obtained for standard phosphorus solutions run through the sample procedure. The procedure is applicable to a variety of gold or silver braze alloys requiring phosphorus analysis

  8. Opposite effects of flurbiprofen and the nitroxybutyl ester of flurbiprofen on apoptosis in cultured guinea-pig gastric mucous cells

    Science.gov (United States)

    Johal, Kamaljit; Hanson, Peter J

    2000-01-01

    The nitric oxide (NO)-donating nitroxybutyl ester of flurbiprofen (NO-flurbiprofen), shows reduced gastro-intestinal toxicity relative to flurbiprofen. NO may exert either pro- or anti-apoptotic effects, while non-steroidal anti-inflammatory drugs may induce apoptosis. The aim of the present work was therefore to compare the effects of flurbiprofen and NO-flurbiprofen on apoptosis in guinea-pig gastric mucous cells. Apoptotic activity was assessed by assay of caspase activity and from the fragmentation and condensation of nuclei. Incubation with flurbiprofen for 24 h produced a concentration-dependent induction of apoptosis in cells attached to the culture plate (caspase 3-like activity increased by 257% at 500 μM), while NO-flurbiprofen inhibited basal apoptosis (caspase 3-like activity decreased by 71% at 500 μM). Caspase activity and nuclear fragmentation were substantially increased in cells that had spontaneously detached from the culture plate. NO-flurbiprofen inhibited caspase activity (55% at 500 μM) but not nuclear fragmentation in these detached cells. NO flurbiprofen inhibited the activation of apoptosis by 25 μM C6-ceramide in cells attached to the culture plate. Inhibition of caspase activity by NO-flurbiprofen was detectable after 6 h of incubation with intact cells, but by contrast with the NO-donor S-nitrosyl-N-acetyl-penicillamine, was not demonstrable with cell homogenates. Activation of caspase 3-like activity by flurbiprofen was slow (>6 h incubation needed) and was inhibited by cycloheximide. The presence of a nitroxybutyl ester moiety on flurbiprofen prevents the pro-apoptotic activity of the parent compound and may contribute to the reduced gastro-intestinal toxicity of NO-flurbiprofen. PMID:10864887

  9. Biological nitrogen and phosphorus removal by filamentous bacteria ...

    African Journals Online (AJOL)

    The availability of excess nutrients (phosphorus (P) and nitrogen (N)) in wastewater systems causes many water quality problems. These problems include eutrophication whereby algae grow excessively and lead to depletion of oxygen, death of the aquatic life and bad odours. Biological phosphorus removal has gained ...

  10. Phosphorus Processing—Potentials for Higher Efficiency

    OpenAIRE

    Ludwig Hermann; Fabian Kraus; Ralf Hermann

    2018-01-01

    In the aftermath of the adoption of the Sustainable Development Goals (SDGs) and the Paris Agreement (COP21) by virtually all United Nations, producing more with less is imperative. In this context, phosphorus processing, despite its high efficiency compared to other steps in the value chain, needs to be revisited by science and industry. During processing, phosphorus is lost to phosphogypsum, disposed of in stacks globally piling up to 3–4 billion tons and growing by about 200 million ...

  11. Regulation of phosphorus uptake and utilization: transitioning from current knowledge to practical strategies

    OpenAIRE

    Hasan, Md. Mahmudul; Hasan, Md. Mainul; Teixeira da Silva, Jaime A.; Li, Xuexian

    2016-01-01

    Phosphorus is a poorly bioavailable macronutrient that is essential for crop growth and yield. Overuse of phosphorus fertilizers results in low phosphorus use efficiency (PUE), has serious environmental consequences and accelerates the depletion of phosphorus mineral reserves. It has become extremely challenging to improve PUE while preserving global food supplies and maintaining environmental sustainability. Molecular and genetic analyses have revealed the primary mechanisms of phosphorus up...

  12. Phosphorus-defect interactions during thermal annealing of ion implanted silicon

    Science.gov (United States)

    Keys, Patrick Henry

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

  13. Prevention of refinery tower plugging by residual oil gellant chemicals in crude : pilot plant evaluation of alternative oil gellants

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, R.S.; Fyten, G.C.; Tamayo, C.; Funkhouser, G.P. [Haliburton, Houston, TX (United States); Lemieux, A.; Blackmore, T. [Omnicon Consultants Inc., Calgary, AB (Canada)

    2007-07-01

    Previous studies have described refinery plugging caused by volatile phosphorus components originating from phosphate ester oil gellants as well as two successful field trials of new phosphonate ester oil gellants, which were demonstrated to address this problem. Additional field testing of phosphonate ester gellants directed at optimization of cost and performance has also been previously studied. This paper presented the results of a follow-up study to these previous investigations, as new modified phosphate ester systems were expected to become commercial that would reduce volatile phosphorus. Several questions that required further investigation were discussed in this paper. These included the comparative ability of phosphonate and modified phosphate esters to control volatile phosphorus; tower fouling at higher temperatures in the presence of steam; and, organic halide formations under distillation tower conditions. The paper presented the results of full-scale pilot plant testing that was performed over several days with flowback captured after actual fracturing treatments in order to serve as a guide to the selection of oil gellant systems for reduction of refinery tower and heat exchanger fouling. The study measured fouling of a tray inserted in the pilot plant distillation tower as well as fouling of the packing material. Any changes in operating parameters such as rate, temperature, or pressure over the time of each test were also noted, as these could also be indicative of fouling. 3 refs., 2 tabs., 17 figs.

  14. Serum Phosphorus Concentrations in the Third National Health and Nutrition Examination Survey (NHANES III)

    Science.gov (United States)

    de Boer, Ian H.; Rue, Tessa C.; Kestenbaum, Bryan

    2011-01-01

    Background Higher serum phosphorus concentrations within the normal laboratory range have been associated with cardiovascular events and mortality in large prospective cohort studies of individuals with and without kidney disease. Reasons for interindividual variation in steady-state serum phosphorus concentrations are largely unknown. Study Design Cross-sectional study. Setting & Participants 15,513 participants in the Third National Health and Nutrition Examination Survey. Predictors Demographic data, dietary intake measured by means of 24-hour dietary recall and food-frequency questionnaire, and established cardiovascular risk factors. Outcome & Measurements Serum phosphorus concentration. Results Mean serum phosphorus concentrations were significantly greater in women (+0.16 mg/dL versus men; P phosphorus and phosphorus-rich foods were associated only weakly with circulating serum phosphorus concentrations, if at all. Higher serum phosphorus levels were associated with lower calculated Framingham coronary heart disease risk scores, which are based on traditional atherosclerosis risk factors. In aggregate, demographic, nutritional, cardiovascular, and kidney function variables explained only 12% of the variation in circulating serum phosphorus concentrations. Limitations Results may differ with advanced kidney disease. Conclusions Serum phosphorus concentration is weakly related to dietary phosphorus and not related to a diverse array of phosphorus-rich foods in the general population. Factors determining serum phosphorus concentration are largely unknown. Previously observed associations of serum phosphorus concentrations with cardiovascular events are unlikely to be a result of differences in dietary intake or traditional cardiovascular risk factors. PMID:18992979

  15. Phosphorus analysis in milk samples by neutron activation analysis method

    International Nuclear Information System (INIS)

    Oliveira, R.M. de; Cunha, I.I.L.

    1991-01-01

    The determination of phosphorus in milk samples by instrumental thermal neutron activation analysis is described. The procedure involves a short irradiation in a nuclear reactor and measurement of the beta radiation emitted by phosphorus - 32 after a suitable decay period. The sources of error were studied and the established method was applied to standard reference materials of known phosphorus content. (author)

  16. Phosphorus and phytase levels for layer hens

    Directory of Open Access Journals (Sweden)

    Juliana Cristina Ramos Rezende

    2013-02-01

    Full Text Available The objective of this research was to evaluate the performance and bone quality of laying hens after peak production fed diets containing phosphorus levels and phytase. An experiment was conducted with 384 Hy-line distributed in a completely randomized in a factorial 4 x 3 with 4 levels of available phosphorus and 3 levels of phytase. The experimental period was divided into four periods of 28 days, at the end of each cycle were determined experimental feed intake, egg production, egg weight, feed conversion, mortality, and average egg weight, shell thickness, Haugh units and specific gravity. At the end of the experimental period were determined amounts of calcium and phosphorus excreted by the method of total excreta collection and a fowl per experimental unit was sacrificed for collection of bones and evaluation of width, length and level of robustness from femur and tibia. There was interaction between phosphorus levels and phytase on feed intake, feed conversion and percentage of posture. For inclusion levels of phytase all egg quality variables showed no significant differences. The treatments did not affect bone characteristics of laying hens.

  17. Isolation, Fractionation, and Identification of Sucrose Esters from Various Oriental Tobaccos Employing Supercritical Fluids

    Directory of Open Access Journals (Sweden)

    Ashraf-Khorassani M

    2014-12-01

    Full Text Available Isolation, fractionation, and identification of sucrose esters from aged oriental tobacco employing supercritical fluids have been completed. Underivatized sucrose ester-rich extracts were obtained using supercritical CO2 at densities greater than 0.73 g/mL. Lower density CO2 provided extracts with notable amounts of tobacco derived material; yet, no detectable sucrose ester content. Preparative supercritical fluid chromatography (SFC provided for an additional purification of the sucrose ester-enriched fraction after column optimization. Structural assignments of the SFC fractions were facilitated using gas chromatography/mass spectrometry (GC/MS accompanied by N, O-bis(trimethylsilyltrifluoroacetamide-dimethylformamide (BSTFA-DMF derivatization of the free hydroxyl groups and high performance-liquid chromatography/mass spectrometry (HPLC/MS. From a relative quantitative perspective regardless of tobacco type, sucrose esters having an acetyl group on C6 of the glucose function (Group III were in higher concentration compared to both the concentration observed for sucrose ester of Group I (acetyl group on C3 of fructose and sucrose ester of Group II (no acetyl group on either glucose or fructose. Saturated fatty acid constituents were found to range from a maximum total of 18 carbons to a minimum total of 13 carbons. Unsaturated and isomeric fatty acid homologues were detected within the Group II sucrose ester.

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

    Science.gov (United States)

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

    2015-11-01

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

  19. Phosphorus Dynamics along River Continuum during Typhoon Storm Events

    Directory of Open Access Journals (Sweden)

    Ming Fai Chow

    2017-07-01

    Full Text Available Information on riverine phosphorus (P dynamics during typhoon storm events remains scarce in subtropical regions. Thus, this study investigates the spatial and temporal dynamics of riverine phosphorus in a headwater catchment during three typhoon events. Continuous sampling (3 h intervals of stormwater samples and discharge data were conducted at five locations, which represent the upstream, transitional zone, and downstream areas of the main inflow river. The results revealed that the average event mean concentrations (EMCs for total dissolved phosphorus (TDP and particulate phosphorus (PP in the upstream catchment of Fei-Tsui reservoir were 15.66 μg/L and 11.94 μg/L, respectively. There was at least a 1.3-fold increase in flow-weighted concentrations of TDP and PP from the upper to lower reaches of the main stream. PP and TDP were transported either in clockwise or anticlockwise directions, depending on storm intensity and source. The transport of TDP was primarily regulated by the subsurface flow during the storm event. Soluble reactive phosphorus (SRP contributes more than 50% of the TDP load in moderate storms, while extreme storms supply a greater dissolved organic phosphorus (DOP load into the stream. TDP accounted for approximately 50% of TP load during typhoon storms. Mobilization of all P forms was observed from upstream to downstream of the river, except for DOP. A decrease of DOP load on passing downstream may reflect the change in phosphorus form along the river continuum. Peak discharge and antecedent dry days are correlated positively with P fluxes, indicating that river bank erosion and re-suspension of within-channel sediment are the dominant pathways of P during typhoon storm periods.

  20. Transgenic barley (Hordeum vulgare L.) expressing the wheat aluminium resistance gene (TaALMT1) shows enhanced phosphorus nutrition and grain production when grown on an acid soil.

    Science.gov (United States)

    Delhaize, Emmanuel; Taylor, Phillip; Hocking, Peter J; Simpson, Richard J; Ryan, Peter R; Richardson, Alan E

    2009-06-01

    Barley (Hordeum vulgare L.), genetically modified with the Al(3+) resistance gene of wheat (TaALMT1), was compared with a non-transformed sibling line when grown on an acidic and highly phosphate-fixing ferrosol supplied with a range of phosphorus concentrations. In short-term pot trials (26 days), transgenic barley expressing TaALMT1 (GP-ALMT1) was more efficient than a non-transformed sibling line (GP) at taking up phosphorus on acid soil, but the genotypes did not differ when the soil was limed. Differences in phosphorus uptake efficiency on acid soil could be attributed not only to the differential effects of aluminium toxicity on root growth between the genotypes, but also to differences in phosphorus uptake per unit root length. Although GP-ALMT1 out-performed GP on acid soil, it was still not as efficient at taking up phosphorus as plants grown on limed soil. GP-ALMT1 plants grown in acid soil possessed substantially smaller rhizosheaths than those grown in limed soil, suggesting that root hairs were shorter. This is a probable reason for the lower phosphorus uptake efficiency. When grown to maturity in large pots, GP-ALMT1 plants produced more than twice the grain as GP plants grown on acid soil and 80% of the grain produced by limed controls. Expression of TaALMT1 in barley was not associated with a penalty in either total shoot or grain production in the absence of Al(3+), with both genotypes showing equivalent yields in limed soil. These findings demonstrate that an important crop species can be genetically engineered to successfully increase grain production on an acid soil.

  1. Metabolism of nonparticulate phosphorus in an acid bog lake

    International Nuclear Information System (INIS)

    Koenings, J.P.

    1977-01-01

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

  2. Metabolism of nonparticulate phosphorus in an acid bog lake

    Energy Technology Data Exchange (ETDEWEB)

    Koenings, J. P.

    1977-01-01

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

  3. Tribochemical behaviors of phosphite esters and their combinations with alkyl amines

    International Nuclear Information System (INIS)

    Fu, Xisheng; Sun, Lingguo; Zhou, Xuguang; Li, Jianchang; Fan, Bingji; Ren, Tianhui

    2015-01-01

    Highlights: • Investigating the differences of tribological performance between phosphite ester and their combinations with alkyl amines. • The combination of SEM and EDS was used to investigate the worn surface morphology and detect the element distributions and content on the steel surface. • The chemical compositions of the thermal films and tribofilms were characterized by TEY P L-edge and FY P K-edge XANES spectroscopy. • A phosphate and polyphosphate tribofilm was formed after rubbing times of even 10 s, and being formed completely after rubbing times of 10 min. • Phosphite ester forms short-chain polyphosphates, and ammonium phosphite produces medium-chain polyphosphates in the tribfilm. - Abstract: The tribochemical behaviors of dioctylphosphite ester and ditetradecylphosphite ester together with their corresponding combinations with alkyl amines were studied. The results of tribological evaluations showed that the phosphite ester with long alkyl chain exhibited better antiwear performance but worse extreme pressure property than that of the phosphite ester with short alkyl chain. The combinations showed better antiwear performance but worse extreme pressure property than their corresponding phosphite esters. Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were used to investigate the worn surface morphology and the content as well as the distribution of active elements. It can be found that the prorupt edges of worn surface are enriched with phosphoric-oxygenic compounds and less phosphoric-oxygenic compounds were detected in the valley. X-ray absorption near-edge structure (XANES) spectroscopy was employed to explore the chemical nature of the worn surface. The results show that a tribofilm composed of phosphates and polyphosphates is formed on the worn surface. Furthermore, the tribofilm is generated even in a rubbing of 10 s and is formed completely after 10 min rubbing.

  4. Repellent activity of monoterpenoid esters with neurotransmitter amino acids against yellow fever mosquito, Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Nesterkina Mariia

    2018-03-01

    Full Text Available Repellent activity of monoterpenoid esters (1-6 with neurotransmitter amino acids (GABA and glycine was investigated against Aedes aegypti by using a “cloth-patch” assay and compared to reference standard N,N-diethyl-3-methylbenzamide (DEET. Monoterpenoid esters showed repellent activity with minimum effective dosages (MED in the range of 0.031-0.469 mg/cm2. The carvacrol ester of GABA (2, MED of 0.031 ± 0.008 mg/cm2 exhibited the highest repellency of six monoterpenoid esters tested in comparison to the standard repellent DEET (MED of 0.009 ± 0.002 mg/cm2; however, the repellent activity of carvacrol-glycine ester (5 decreased 4-fold compared to the carvacrol-GABA derivative (2. The repellent activities of menthol GABA (1, MED= 0.375 ± 0.000 mg/cm2 and glycine ester (4, MED=0.312 ± 0.063 mg/cm2 were similar The guaiacol-glycine ester (6 was 3.75-fold more efficacious than the guaiacol ester of GABA (3. In the present study, we report repellent efficacy of prolonged exposure to GABA and glycine esters of menthol, carvacrol, guaiacol (1-6 as compared to the repellent activities of their monoterpene moieties alone.

  5. Impact of thermooxidation of phytosteryl and phytostanyl fatty acid esters on cholesterol micellarization in vitro.

    Science.gov (United States)

    Scholz, Birgit; Weiherer, Renate; Engel, Karl-Heinz

    2017-09-01

    The effects of thermooxidation of a phytosteryl/-stanyl and a phytostanyl fatty acid ester mixture on cholesterol micellarization were investigated using an in vitro digestion model simulating enzymatic hydrolysis by cholesterol esterase and subsequent competition of the liberated phytosterols/-stanols with cholesterol for incorporation into mixed micelles. As a first step, relationships between different doses of the ester mixtures and the resulting micellarized cholesterol were established. Subsequent subjection of the thermooxidized ester mixtures to the in vitro digestion model resulted in three principal observations: (i) thermal treatment of the ester mixtures led to substantial decreases of the intact esters, (ii) in vitro digestion of cholesterol in the presence of the thermooxidized ester mixtures resulted in significant increases of cholesterol micellarization, and (iii) the extents of the observed effects on cholesterol micellarization were strongly associated to the remaining contents of intact esters. The loss of efficacy to inhibit cholesterol micellarization due to thermally induced losses of intact esters corresponded to a loss of efficacy that would have been induced by an actual removal of these amounts of esters prior to the in vitro digestion. The obtained results suggest that in particular oxidative modifications of the fatty acid moieties might be responsible for the observed increases of cholesterol micellarization. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. 40 CFR 721.3800 - Formaldehyde, condensated polyoxyethylene fatty acid, ester with styrenated phenol, ethylene...

    Science.gov (United States)

    2010-07-01

    ... polyoxyethylene fatty acid, ester with styrenated phenol, ethylene oxide adduct. 721.3800 Section 721.3800... Formaldehyde, condensated polyoxyethylene fatty acid, ester with styrenated phenol, ethylene oxide adduct. (a... generically as formaldehyde, condensated polyoxyethylene fatty acid, ester with styrenated phenol, ethylene...

  7. Binding of indomethacin methyl ester to cyclooxygenase-2. A computational study.

    Science.gov (United States)

    Sárosi, Menyhárt-Botond

    2018-06-05

    Inhibitors selective towards the second isoform of prostaglandin synthase (cyclooxygenase, COX-2) are promising nonsteroidal anti-inflammatory drugs and antitumor medications. Methylation of the carboxylate group in the relatively nonselective COX inhibitor indomethacin confers significant COX-2 selectivity. Several other modifications converting indomethacin into a COX-2 selective inhibitor have been reported. Earlier experimental and computational studies on neutral indomethacin derivatives suggest that the methyl ester derivative likely binds to COX-2 with a similar binding mode as that observed for the parent indomethacin. However, docking studies followed by molecular dynamics simulations revealed two possible binding modes in COX-2 for indomethacin methyl ester, which differs from the experimental binding mode found for indomethacin. Both alternative binding modes might explain the observed COX-2 selectivity of indomethacin methyl ester. Graphical abstract Binding of indomethacin methyl ester to cyclooxygenase-2.

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

    Science.gov (United States)

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

    2018-03-01

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

  9. Using a phosphorus loss model to evaluate the Kentucky phosphorus index

    Science.gov (United States)

    U.S. Department of Agriculture’s Natural Resource Conservation Service (USDA-NRCS) has recently revised its 590 Nutrient Management Conservation Standard. As part of this revision, USDA-NRCS is requiring states to test the accuracy of their phosphorus (P) index using either measured P loss data or s...

  10. Activities of native and tyrosine-69 mutant phospholipases A2 on phospholipid analogues. A reevaluation of the minimal substrate requirements.

    Science.gov (United States)

    Kuipers, O P; Dekker, N; Verheij, H M; de Haas, G H

    1990-06-26

    The role of Tyr-69 of porcine pancreatic phospholipase A2 in substrate binding was studied with the help of proteins modified by site-directed mutagenesis and phospholipid analogues with a changed head-group geometry. Two mutants were used containing Phe and Lys, respectively, at position 69. Modifications in the phospholipids included introduction of a sulfur at the phosphorus (thionophospholipids), removal of the negative charge at phosphorus (phosphatidic acid dimethyl ester), and reduction (phosphonolipids) or extension (diacylbutanetriol choline phosphate) of the distance between the phosphorus and the acyl ester bond. Replacement of Tyr-69 by Lys reduces enzymatic activity, but the mutant enzyme retains both the stereospecificity and positional specificity of native phospholipase A2. The Phe-69 mutant not only hydrolyzes the Rp isomer of thionophospholipids more efficiently than the wild-type enzyme, but the Sp thiono isomer is hydrolyzed too, although at a low (approximately 4%) rate. Phosphonolipids are hydrolyzed by native phospholipase A2 about 7 times more slowly than natural phospholipids, with retention of positional specificity and a (partial) loss of stereospecificity. The dimethyl ester of phosphatidic acid is degraded efficiently in a calcium-dependent and positional-specific way by native phospholipase A2 and by the mutants, indicating that a negative charge at phosphorus is not an absolute substrate requirement. The activities on the phosphatidic acid dimethyl ester of native enzyme and the Lys-69 mutant are lower than those on the corresponding lecithin, in contrast to the Phe-69 mutant, which has equal activities on both substrates.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Forms of newly retained phosphorus in mineral soils

    Directory of Open Access Journals (Sweden)

    Armi Kaila

    1964-01-01

    Full Text Available The distribution of soluble phosphate in various fractions of soil phosphorus was studied by treating 1 g-samples of 180 mineral soils with 50 ml of a KH2PO4- solution containing P 5 mg/l for 24 hours, and carrying out the fractionation by the method of CHANG and JACKSON after the solution was removed and the moist samples had stood for 3 days at room temperature. The amount of retained phosphorus in the different fractions was computed by taking the difference between the treated and check samples. In the 70 samples of clay soils, the mean proportion of the retained phosphorus was 57 per cent of the 250 mg/kg applied, in the 62 samples of the sand and fine sand soils the corresponding part was 45 per cent, and in the 48 samples of loam and silt soils it was 44 per cent. The higher retention in the clay soils was mainly due to a higher retention in the alkali-soluble fraction. The net increase in the fluoride-soluble forms was of the same order in these three soil groups. On the average, more than 95 per cent of the sorbed phosphorus was found in the fluoride-soluble and alkali-soluble fractions. In one third of the samples a low net increase in the acid soluble fraction was detected, but this may be partly due to changes in the solubility of the native phosphorus in the treated samples. Owing to the fairly large variation, the tendency to somewhat higher mean values for the sorption in the subsoils compared with those of the topsoils was not statistically significant. The ratio between the sorbed amounts of fluoride-soluble and alkali soluble forms was higher in the sand and fine sand soils than in the clay soils. Only in 15 samples, most of them Litorina-soils, the net increase in the alkali-soluble forms was higher than in the fluoride-soluble fraction. Probably, because an equilibrium in the phosphorus conditions was not yet reached at the end of the treatment, the attempt failed to find any clear connection between the distribution of the

  12. Methyl and ethyl soybean esters production

    Energy Technology Data Exchange (ETDEWEB)

    Pighinelli, Anna Leticia Montenegro Turtelli; Park, Kil Jin; Zorzeto, Thais Queiroz [Universidade Estadual de Campinas (FEAGRI/UNICAMP), SP (Brazil). Fac. de Engenharia Agricola], E-mail: annalets@feagri.unicamp.br; Bevilaqua, Gabriela [Universidade Estadual de Campinas (IQ/UNICAMP), SP (Brazil). Inst. de Quimica

    2008-07-01

    Biodiesel is a fuel obtained from triglycerides found in nature, like vegetable oils and animal fats. Nowadays it has been the subject of many researches impulses by the creation of the Brazilian law that determined the blend of 2% of biodiesel with petrodiesel. Basically, there are no limitations on the oilseed type for chemical reaction, but due to high cost of this major feedstock, it is important to use the grain that is available in the region of production. Soybean is the oilseed mostly produced in Brazil and its oil is the only one that is available in enough quantity to supply the current biodiesel demand. The objective of this work was to study the effects of reaction time and temperature on soybean oil transesterification reaction with ethanol and methanol. A central composite experimental design with five variation levels was used and response surface methodology applied for the data analysis. The statistical analysis of the results showed that none of the factors affected the ethyl esters production. However, the methyl esters production suffered the influence of temperature (linear effect), reaction time (linear and quadratic) and interaction of these two variables. None of the generated models showed significant regression consequently it was not possible to build the response surface. The experiments demonstrated that methanol is the best alcohol for transesterification reactions and the ester yield was up to 85%. (author)

  13. The influence of phosphorus on the corrosion of iron in calcium nitrate

    International Nuclear Information System (INIS)

    Windisch, C.F. Jr.; Baer, D.R.; Jones, R.H.; Engelhard, M.H.

    1992-01-01

    This paper reports that intergranular stress corrosion cracking (IGSCC) of metallic alloys including iron is strongly influenced by the presence of grain boundary impurities such as phosphorus. In this study to determine how phosphorus affects the corrosion of ion, electrochemical polarization methods were used in conjunction with surface analyses employing ultrahigh vacuum transfer. Specifically, these methods were used to examine the corrosion of iron, iron/phosphorus alloys, and iron implanted with phosphorus in deaerated 55 weight percent Ca(NO 3 ) 2 solutions at 60 degrees C. The presence of phosphorus in iron accelerated corrosion in both the active and passive regions, with the effect being more pronounced in the passive region. In the active region, the phosphorus was oxidized to phosphate which, in turn, appeared to assist the dissolution of the semiprotective Fe 3 O 4 . In the passive region, the phosphorus (when unoxidized) accelerated corrosion by some other mechanism. The FePO 4 that formed in the passive region did not inhibit passivation by, rather, was incorporated in the passive film. The chemical transformations would appear to explain, at least partly, the high IGSCC rates observed for ion containing phosphorus segregated at grain boundaries

  14. Radiochemical studies of some preparation methods for phosphorus

    International Nuclear Information System (INIS)

    Loos-Neskovic, C.; Fedoroff, M.

    1983-01-01

    Various methods of radiochemical separation were tested for the determination of phosphorus in metals and alloys by neutron activation analysis. Classical methods of separation revealed some defects when they were applied to this problem. Methods using liquid extraction gave low yields and were not reproducible. Methods based on precipitation gave better results, but were not selective enough in most cases. Retention on alumina was not possible without preliminary separations. Authors studied a new radiochemical separation based on the extraction of elemental phosphorus in the gaseous phase after reduction at high temperature with carbon. Measurements with radioactive phosphorus showed that the extraction yield is better than 99%. (author)

  15. A new, direct analytical method using LC-MS/MS for fatty acid esters of 3-chloro-1,2-propanediol (3-MCPD esters) in edible oils.

    Science.gov (United States)

    Yamazaki, K; Ogiso, M; Isagawa, S; Urushiyama, T; Ukena, T; Kibune, N

    2013-01-01

    A new, direct analytical method for the determination of 3-chloro-1,2-propanediol fatty acid esters (3-MCPD esters) was developed. The targeted 3-MCPD esters included five types of monoester and 25 [corrected] types of diester. Samples (oils and fats) were dissolved in a mixture of tert-butyl methyl ether and ethyl acetate (4:1), purified using two solid-phase extraction (SPE) cartridges (C(18) and silica), then analysed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Five monoesters and five diesters with the same fatty acid group could be separated and quantified. Pairs of 3-MCPD diesters carrying the same two different fatty acid groups, but at reversed positions (sn-1 and sn-2), could not be separated and so were expressed as a sum of both compounds. The limits of quantification (LOQs) were estimated to be between 0.02 to 0.08 mg kg(-1), depending on the types of 3-MCPD ester. Repeatability expressed as relative standard deviation (RSD(r)%) varied from 5.5% to 25.5%. The new method was shown to be applicable to various commercial edible oils and showed levels of 3-MCPD esters varying from 0.58 to 25.35 mg kg(-1). The levels of mono- and diesters ranged from 0.10 to 0.69 mg kg(-1) and from 0.06 to 16 mg kg(-1), respectively.

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

    Science.gov (United States)

    Marinozzi, Maura; Pertusati, Fabrizio; Serpi, Michaela

    2016-11-23

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

  17. Increased large VLDL particles confer elevated cholesteryl ester transfer in diabetes

    NARCIS (Netherlands)

    Dullaart, Robin P. F.; de Vries, Rindert; Kwakernaak, Arjan J.; Perton, Frank; Dallinga-Thie, Geesje M.

    BackgroundPlasma cholesteryl ester transfer (CET), reflecting transfer of cholesteryl esters from high density lipoproteins (HDL) towards apolipoprotein B-containing lipoproteins, may promote atherosclerosis development, and is elevated in Type 2 diabetes mellitus (T2DM). We determined the extent to

  18. METODE ESTIMASI PROPERTI KRITIS UAP-CAIR KOMPONEN MURNI ESTER

    Directory of Open Access Journals (Sweden)

    Dhoni Hartantoa

    2014-03-01

    Full Text Available Biodiesel become eco-friendly renewable energy resources which is consisted of monoalkyl ester or long chain fatty acid from plants or animal. Biodiesel has more advantage than petrodiesel. Property of pure compound such as critical properties are the important thing to determine chemical mixtures behavior and also as base of equation of state. Joback method can show good results in estimating critical properties of monoalkyl ester.

  19. Triphenyltin derivatives of sulfanylcarboxylic esters.

    Science.gov (United States)

    Casas, José S; Couce, María D; Sánchez, Agustín; Seoane, Rafael; Sordo, José; Perez-Estévez, Antonio; Vázquez-López, Ezequiel

    2018-03-01

    The reaction of 3-(aryl)-2-sulfanylpropenoic acids [H 2 xspa; x: p=3-phenyl-, f=3-(2-furyl)-, t=3-(2-thienyl)-] with methanol or ethanol gave the corresponding methyl (Hxspme) or ethyl (Hxspee) esters. The reaction of these esters (HL) with triphenyltin(IV) hydroxide gave compounds of the type [SnPh 3 L], which were isolated and characterized as solids by elemental analysis, IR spectroscopy and mass spectrometry and in solution by multinuclear ( 1 H, 13 C and 119 Sn) NMR spectroscopy. The structures of [SnPh 3 (pspme)], [SnPh 3 (fspme)] and [SnPh 3 (fspee)] were determined by X-ray diffractometry and the antimicrobial activity against E. coli, S. aureus, B. subtilis, P. aeruginosa, Resistant P. aeruginosa (a strain resistant to 'carbapenem'), and C. albicans was tested and the in vitro cytotoxic activity against the HeLa-229, A2780 and A2780cis cell lines was determined for all compounds. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Phosphorus fractions and its potential release in the sediments of Koycegiz Lake, Turkey

    Directory of Open Access Journals (Sweden)

    Yalçın Şahin

    2012-12-01

    Full Text Available This study was conducted to find out the seasonal and spatial patterns of the phosphorus in the littoral sediment and its potential release into the Koycegiz Lake, south west Turkey, between November 2011 and March 2012 at two months intervals. The scanning electron microscopy was used for elemental compositions of the sediment. The amounts and forms of phosphorus (P in surface sediments of Koycegiz Lake were examined using a not sequential chemical extraction procedure. Four fractions of sedimentary P, including organic bound phosphorus fraction (Org≈P, calcium bound phosphorus fraction (Ca≈P, iron+aluminium bound phosphorus fraction (Fe+Al≈P and carbonate bound phosphorus fraction (CO3≈P were separately quantified. The results indicated that the contents of different phosphorus fractions in the sediments varied greatly. The proportion of phosphorus fractions was estimated as Org≈P (90.20 %, this fraction was followed by Ca≈P (9.06 %, Fe+Al≈P (0.47 % and CO3≈P (0.27 % in this study. The level of phosphorus release from the sediment to the lake is calculated as low. The sediment phosphorus release fluctuated between -6.647–75.883 μg/m2.d-1 and the total phosphorus (TP concentrations of the sediment samples were changed between 980.39 μg/gDW (Dry Weight - 1990.81 μg/gDW. The results show that it can be evaluation as eutrophic for Koycegiz Lake.

  1. Atomic and electronic structure of exfoliated black phosphorus

    International Nuclear Information System (INIS)

    Wu, Ryan J.; Topsakal, Mehmet; Jeong, Jong Seok; Wentzcovitch, Renata M.; Mkhoyan, K. Andre; Low, Tony; Robbins, Matthew C.; Haratipour, Nazila; Koester, Steven J.

    2015-01-01

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

  2. Stereoselective formation of a cholesterol ester conjugate from fenvalerate by mouse microsomal carboxyesterase(s).

    Science.gov (United States)

    Miyamoto, J; Kaneko, H; Takamatsu, Y

    1986-06-01

    In accordance with in vivo findings, of the four chiral isomers of fenvalerate (S-5602 Sumicidin, Pydrin, [RS]-alpha-cyano-3-phenoxybenzyl [RS]-2-(4-chlorophenyl)isovalerate), only the [2R, alpha S]-isomer (B-isomer) yielded cholesteryl [2R]-2-(4-chlorophenyl)isovalerate (CPIA-cholesterol ester) in the in vitro study using several tissue homogenates of mice, rats, dogs, and monkeys. There were species differences in the extent of CPIA-cholesterol-ester formation, with mouse tissues showing relatively higher activity than those of other animals. The kidney, brain, and spleen of mice showed relatively higher capacities to form this ester compared to other tissues, and the enzyme activity was mainly localized in microsomal fractions. The CPIA-cholesterol ester did not seem to be produced by three known biosynthetic pathways of endogenous cholesterol esters--acyl-CoA:cholesterol O-acyltransferase (ACAT), lecithin:cholesterol O-acyltransferase (LCAT), and cholesterol esterase. Carboxyesterase(s) of mouse kidney microsomes solubilized by digitonin hydrolyzed only the B alpha-isomer of fenvalerate, yielding CPIA, whereas they yielded the corresponding cholesterol ester in the presence of artificial liposomes containing cholesterol. Thus, it appears that the stereoselective formation of the CPIA-cholesterol ester results from the stereoselective formation of the CPIA-carboxyesterase complex only from the B alpha-isomer, which subsequently undergoes cleavage by cholesterol to yield the CPIA-cholesterol ester.

  3. Production of wax esters via microbial oil synthesis from food industry waste and by-product streams.

    Science.gov (United States)

    Papadaki, Aikaterini; Mallouchos, Athanasios; Efthymiou, Maria-Nefeli; Gardeli, Chryssavgi; Kopsahelis, Nikolaos; Aguieiras, Erika C G; Freire, Denise M G; Papanikolaou, Seraphim; Koutinas, Apostolis A

    2017-12-01

    The production of wax esters using microbial oils was demonstrated in this study. Microbial oils produced from food waste and by-product streams by three oleaginous yeasts were converted into wax esters via enzymatic catalysis. Palm oil was initially used to evaluate the influence of temperature and enzyme activity on wax ester synthesis catalysed by Novozyme 435 and Lipozyme lipases using cetyl, oleyl and behenyl alcohols. The highest conversion yields (up to 79.6%) were achieved using 4U/g of Novozyme 435 at 70°C. Transesterification of microbial oils to behenyl and cetyl esters was achieved at conversion yields up to 87.3% and 69.1%, respectively. Novozyme 435 was efficiently reused for six and three cycles during palm esters and microbial esters synthesis, respectively. The physicochemical properties of microbial oil derived behenyl esters were comparable to natural waxes. Wax esters from microbial oils have potential applications in cosmetics, chemical and food industries. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Well-Defined Poly(Ortho Ester Amides) for Potential Drug Carriers: Probing the Effect of Extra- and Intracellular Drug Release on Chemotherapeutic Efficacy.

    Science.gov (United States)

    Yan, Guoqing; Wang, Jun; Qin, Jiejie; Hu, Liefeng; Zhang, Panpan; Wang, Xin; Tang, Rupei

    2017-07-01

    To compare the chemotherapeutic efficacy determined by extra- and intracellular drug release strategies, poly(ortho ester amide)-based drug carriers (POEAd-C) with well-defined main-chain lengths, are successfully constructed by a facile method. POEAd-C3-doxorubicin (DOX) can be rapidly dissolved to release drug at tumoral extracellular pH (6.5-7.2), while POEAd-C6-DOX can rapidly release drug following gradual swelling at intracellular pH (5.0-6.0). In vitro cytotoxicity shows that POEAd-C3-DOX exhibits more toxic effect on tumor cells than POEAd-C6-DOX at extracellular pH, but POEAd-C6-DOX has stronger tumor penetration and inhibition in vitro and in vivo tumor models. So, POEAd-C6-DOX with the intracellular drug release strategy has stronger overall chemotherapeutic efficacy than POEAd-C3-DOX with extracellular drug release strategy. It is envisioned that these poly(ortho ester amides) can have great potential as drug carriers for efficient chemotherapy with further optimization. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Three new fatty acid esters from the mushroom Boletus pseudocalopus.

    Science.gov (United States)

    Kim, Ki Hyun; Choi, Sang Un; Lee, Kang Ro

    2012-06-01

    A bioassay-guided fractionation and chemical investigation of a MeOH extract of the Korean wild mushroom Boletus pseudocalopus resulted in the identification of three new fatty acid esters, named calopusins A-C (1-3), along with two known fatty acid methyl esters (4-5). These new compounds are structurally unique fatty acid esters with a 2,3-butanediol moiety. Their structures were elucidated through 1D- and 2D-NMR spectroscopic data and GC-MS analysis as well as a modified Mosher's method. The new compounds 1-3 showed significant inhibitory activity against the proliferation of the tested cancer cell lines with IC(50) values in the range 2.77-12.51 μM.

  6. STOCHASTIC MODELING OF COMPRESSIVE STRENGTH OF PHOSPHORUS SLAG CONTENT CEMENT

    Directory of Open Access Journals (Sweden)

    Ali Allahverdi

    2016-07-01

    Full Text Available One of the common methods for quick determination of compressive strength as one of the most important properties for assessment of cement quality is to apply various modeling approaches. This study is aimed at finding a model for estimating the compressive strength of phosphorus slag content cements. For this purpose, the compressive strengths of chemically activated high phosphorus slag content cement prepared from phosphorus slag (80 wt.%, Portland cement (14 wt.% and a compound chemical activator containing sodium sulfate and anhydrite (6 wt.% were measured at various Blaine finenesses and curing times. Based on the obtained results, a primary stochastic model in terms of curing time and Blaine fineness has been developed. Then, another different dataset was used to incorporate composition variable including weight fractions of phosphorus slag, cement, and activator in the model. This model can be effectively used to predict the compressive strength of phosphorus slag content cements at various Blaine finenesses, curing times, and compositions.

  7. Influence of phosphorus on point defects in an austenitic alloy

    International Nuclear Information System (INIS)

    Boulanger, L.

    1988-06-01

    The influence of phosphorus on points defects clusters has been studied in an austenitic alloy (Fe/19% at. Cr/13% at. Ni). Clusters are observed by transmission electron microscopy. After quenching and annealing, five types of clusters produced by vacancies or phosphorus-vacancies complexes are observed whose presence depends on cooling-speed. Vacancy concentration (with 3.6 10 -3 at. P) in clusters is about 10 -5 and apparent vacancy migration is 2 ± 0.1 eV. These observations suggest the formation of metastable small clusters during cooling which dissociate during annealing and migrate to create the observed clusters. With phosphorus, the unfrequent formation of vacancy loops has been observed during electron irradiation. Ions irradiations show that phosphorus does not favour nucleation of interstitial loops but slowers their growth. It reduces swelling by decreasing voids diameter. Phosphorus forms vacancy complexes whose role is to increase the recombination rate and to slow vacancy migration [fr

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

    Energy Technology Data Exchange (ETDEWEB)

    Doganov, Rostislav A.; Özyilmaz, Barbaros [Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore, 6 Science Drive 2, 117546 Singapore (Singapore); Department of Physics, National University of Singapore, 2 Science Drive 3, 117542 Singapore (Singapore); Graduate School for Integrative Sciences and Engineering (NGS), National University of Singapore, 28 Medical Drive, 117456 Singapore (Singapore); Koenig, Steven P.; Yeo, Yuting [Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore, 6 Science Drive 2, 117546 Singapore (Singapore); Department of Physics, National University of Singapore, 2 Science Drive 3, 117542 Singapore (Singapore); Watanabe, Kenji; Taniguchi, Takashi [National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044 (Japan)

    2015-02-23

    Ultrathin black phosphorus, or phosphorene, is a two-dimensional material that allows both high carrier mobility and large on/off ratios. Similar to other atomic crystals, like graphene or layered transition metal dichalcogenides, the transport behavior of few-layer black phosphorus is expected to be affected by the underlying substrate. The properties of black phosphorus have so far been studied on the widely utilized SiO{sub 2} substrate. Here, we characterize few-layer black phosphorus field effect transistors on hexagonal boron nitride—an atomically smooth and charge trap-free substrate. We measure the temperature dependence of the field effect mobility for both holes and electrons and explain the observed behavior in terms of charged impurity limited transport. We find that in-situ vacuum annealing at 400 K removes the p-doping of few-layer black phosphorus on both boron nitride and SiO{sub 2} substrates and reduces the hysteresis at room temperature.

  9. Improvement of Fructanohydrolase Production in Aspergillus niger SL-09 by Sucrose Ester

    Directory of Open Access Journals (Sweden)

    Xiang-Yang Ge

    2006-01-01

    Full Text Available The influence of carbon sources, nitrogen sources, and the addition of sucrose ester on fructanohydrolase production was investigated. The enzyme production varied depending on the carbon source. Apart from that, it was found that the enzyme activities formed by Aspergillus niger SL-09 were enhanced dramatically by the addition of sucrose ester S-770 to the medium. The effect of sucrose ester on enzyme production was also studied on molecular level, and it was confirmed that the transcription was activated by the addition of sucrose ester to the medium. The response surface methodology (RSM was used to optimize the composition for the production of fructanohydrolase, and the enzyme activities were enhanced more than 7-fold than those obtained in the basal medium.

  10. Charged particle activation analysis of phosphorus in biological materials

    International Nuclear Information System (INIS)

    Masumoto, K.; Yagi, M.

    1983-01-01

    Charged particle activation analysis of phosphorus in biological materials using the 31 P(α,n) sup(34m)Cl reaction has been studied. Since sup(34m)Cl is also produced by the 32 S(α,pn) and the 35 Cl(α,α'n) reactions, the thick-target yield curves on phosphorus, sulfur and chlorine were determined in order to choose the optimum irradiation conditions. As a result, it was found that the activation analysis for phosphorus without interferences from sulfur and chlorine is possible by bombarding with less than 17 MeV alphas. The applicability of this method to biological samples was then examined by irradiating several standard reference materials. It was confirmed that phosphorus can readily be determined at the detection limit of 1μg free from interferences due to the matrix elements. (author)

  11. One-pot synthesis of thermoplastic mixed paramylon esters using trifluoroacetic anhydride.

    Science.gov (United States)

    Shibakami, Motonari; Tsubouchi, Gen; Sohma, Mitsugu; Hayashi, Masahiro

    2015-03-30

    Mixed paramylon esters prepared from paramylon (a storage polysaccharide of Euglena), acetic acid, and a long-chain fatty acid by one-pot synthesis using trifluoroacetic anhydride as a promoter and solvent were shown to have thermoplasticity. Size exclusion chromatography indicated that the mixed paramylon esters had a weight average molecular weight of approximately 4.9-6.7×10(5). Thermal analysis showed that these esters were stable in terms of the glass transition temperature (>90°C) and 5% weight loss temperature (>320°C). The degree of substitution of the long alkyl chain group, a dominant factor determining thermoplasticity, was controlled by tuning the feed molar ratio of acetic acid and long-chain fatty acid to paramylon. These results implied that the one-pot synthesis is useful for preparing structurally-well defined thermoplastic mixed paramylon esters with high molecular weight. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Hydrolytic Stability of Boronate Ester-Linked Covalent Organic Frameworks

    KAUST Repository

    Li, Huifang

    2018-01-30

    The stability of covalent organic frameworks (COFs) is essential to their applications. However, the common boronate ester-linked COFs are susceptible to attack by nucleophiles (such as water molecules) at the electron-deficient boron sites. To provide an understanding of the hydrolytic stability of the representative boronate ester-linked COF-5 and of the associated hydrolysis mechanisms, density functional theory (DFT) calculations were performed to characterize the hydrolysis reactions of the molecule formed by the condensation of 1,4-phenylenebis(boronic acid) (PBBA) and 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP) monomers; two cases were considered, one dealing with the freestanding molecule and the other with the molecule interacting with COF layers. It was found that the boronate ester (B–O) bond dissociation, which requires one H2O molecule, has a relatively high energy barrier of 22.3 kcal mol−1. However, the presence of an additional H2O molecule significantly accelerates hydrolysis by reducing the energy barrier by a factor of 3. Importantly, the hydrolysis of boronate ester bonds situated in a COF environment follows reaction pathways that are different and have increased energy barriers. These results point to an enhanced hydrolytic stability of COF-5 crystals.

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

    Science.gov (United States)

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

    2017-12-01

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

  14. Substoichiometric determination of phosphorus

    International Nuclear Information System (INIS)

    Shigematsu, T.; Kudo, K.

    1981-01-01

    Phosphorus in orchard leaves (NBS SRM-1571) and spinach (SRM-1570) was determined by various substoichiometric analytical methods such as the direct method, Gravshchenko's method and the method of carrier amount variation. All samples were labelled with 32 P radioisotope. The data obtained by the method of carrier amount variation were also treated by the method of least squares instead of De Voe's method. Phosphorus concentration in orchard leaves was 0.206+-0.011% by the direct method, 0.219+-0.011% by Gravshchenko's method, 0.211+-0.011% by the method of carrier amount variation and 0.207+-0.007% by the method of least squares, respectively. These values agree with the value reported by NBS (0.21+-0.01%). Furthermore, these concentrations obtained by various substoichiometric methods were compared with those by radioactivation reported in a previous paper. (author)

  15. Effects of Nitrogen and Phosphorus Fertilizer on Agro ...

    African Journals Online (AJOL)

    SH

    caraway plant (Carum carvi) grown from root tubers when phosphorus was applied at the rate of 40 kg/ ha. The significant reduction in the number of days to first flower appearance, number of days to 50% flower appearance and first fruit maturity with increasing rates of phosphorus fertilizer showed that well P-fertilized T.

  16. PHOSPHORUS-BEARING MOLECULES IN MASSIVE DENSE CORES

    Energy Technology Data Exchange (ETDEWEB)

    Fontani, F.; Rivilla, V. M. [INAF-Osservatorio Astrofisico di Arcetri, L.go E. Fermi 5, I-50125 Firenze (Italy); Caselli, P.; Vasyunin, A. [Max-Planck-Institute for Extraterrestrial Physics, Giessenbachstrasse, D-85748 Garching (Germany); Palau, A. [Instituto de Radioastronomía y Astrofísica, Universidad Nacional Autónoma de México, P.O. Box 3-72, 58090 Morelia, Michoacán, México (Mexico)

    2016-05-10

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

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

    Science.gov (United States)

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

    2018-02-01

    Population growth, urban expansion and intensive agriculture and thus increased use of fertilizers aimed at increasing the production capacity cause extensive loss of nutrients such as nitrogen and phosphorus and lead to reduced quality of soil and water. Therefore, identification of nutrients in the soil and their potential are essential. The aim of this study was to evaluate the capability of the SWAT model in simulating runoff, sediment, and nitrogen and phosphorus losses in Tamer catchment. Runoff and sediment measured at Tamar gauging station were used to calibrate and validate the model. Simulated values were generally consistent with the data observed during calibration and validation period (0.6 organic nitrogen and nitrate and soluble phosphorus and mineral phosphorus attached to the sediments showed the greatest sensitivity to the type of land use. Results also showed that the average nutrient loss caused by erosion in this catchment, was 6.99 kg/ha for nitrogen, 0.35 kg/ha for nitrate, 1.3 kg/ha for organic phosphorus, 0.015 kg/ha for soluble phosphorus, and 0.45 kg/ha for mineral phosphorus.

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

    Science.gov (United States)

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

    2014-01-01

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

  19. Phosphorus and nitrogen regulate arbuscular mycorrhizal symbiosis in Petunia hybrida.

    Science.gov (United States)

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

    2014-01-01

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

  20. Chemical modifications of Sterculia foetida L. oil to branched ester derivatives

    NARCIS (Netherlands)

    Manurung, Robert; Daniel, Louis; van de Bovenkamp, Hendrik H.; Buntara, Teddy; Maemunah, Siti; Kraai, Gerard; Makertihartha, I. G. B. N.; Broekhuis, Antonius A.; Heeres, Hero J.

    An experimental study to modify Sterculia foetida L. oil (STO) or the corresponding methyl esters (STO FAME) to branched ester derivatives is reported. The transformations involve conversion of the cyclopropene rings in the fatty acid chains of STO through various catalytic as well as stoichiometric