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Sample records for ammonium molybdate vi

  1. Catalytic coal liquefaction. Quarterly report, October-December 1981. [Ammonium molybdates

    SciTech Connect

    Weller, S.W.

    1981-01-01

    This research has the following scope and objectives: (1) to characterize supported molybdena catalysts, in the sulfide as well as in the oxide form, with respect to total surface area, specific surface area by oxygen chemisorption, and catalytic activity in a standardized test reaction; (2) to study the effect of preparational variables in the liquefaction of coal with efficient catalysts, with particular emphasis on molybdenum catalysts employed in very small amount. Summary of progress do date - Tubing bomb experiments on the transfer of hydrogen from tetralin to coal have been extended to a series of impregnated metal salts and two acids, all at 1% concentration. Coal conversion, moderately high even with no catalyst, is incrementally higher with all catalysts tested. Apparent hydrogen transfer, based on naphthalene produced, is also increased by all catalysts but especially by ammonium molybdate (AM) and stannous chloride (SnCl/sub 2/). Blank runs with catalyst but no coal show a finite amount of naphthalene production; except for AM and SnCl/sub 2/, the apparent catalysis of hydrogen transfer may be an artifact associated with a catalytic effect on tetralin dissociation. This question is being examined in autoclave runs, where the gas volume: liquid volume is greater. Runs at 400/sup 0/C indicate a surprising effect: both coal and AM separately catalyze tetralin dissociation, but their combined effect is greater than the sum of the individual ones (synergy). The possibility that catalytic generation of radicals from coal in turn catalyzes tetralin dissociation is being studied at 450/sup 0/C with bibenzyl as a radical generator. 3 tables.

  2. Combination of Pichia membranifaciens and ammonium molybdate for controlling blue mould caused by Penicillium expansum in peach fruit.

    PubMed

    Cao, Shifeng; Yuan, Yongjun; Hu, Zhichao; Zheng, Yonghua

    2010-07-15

    The potential enhancement of Pichia membranifaciens by ammonium molybdate (NH(4)Mo) to control blue mould caused by Penicillium expansum on peach fruit was investigated. Combining P. membranifaciens at 1x10(8) cell/ml with 1 mM NH(4)Mo provided a more effective control of blue mould rot than applying the yeast or NH(4)Mo alone. Addition of 1 mM NH(4)Mo significantly increased the growth of P. membranifaciens in peach wounds, but did not affect the population in nutrient yeast dextrose broth medium. The in vitro experiment showed that the combined treatment inhibited spore germination and germ tube elongation of P. expansum in comparison with the treatment of P. membranifaciens or NH(4)Mo alone. Moreover, P. membranifaciens, NH(4)Mo, and the combination of them did not impair the quality parameters including fruit firmness and content of total soluble solids, titratable acidity and vitamin C of peach fruit after 6 days of storage at 20 degrees C. These results suggested that the use of NH(4)Mo is a useful approach to improve the efficacy of P. membranifaciens for postharvest disease control in peach fruit. PMID:20605650

  3. Characterization of arsenic (V) and arsenic (III) in water samples using ammonium molybdate and estimation by graphite furnace atomic absorption spectroscopy.

    PubMed

    Sounderajan, Suvarna; Udas, A C; Venkataramani, B

    2007-10-01

    Arsenic (V) is known to form heteropolyacid with ammonium molybdate in acidic aqueous solutions, which can be quantitatively extracted into certain organic solvents. In the present work, 12-molybdoarsenic acid extracted in butan-1-ol is used for quantification of As (V). Total arsenic is estimated by converting arsenic (III) to arsenic (V) by digesting samples with concentrated nitric acid before extraction. Concentration of As (III) in the sample solutions could be calculated by the difference in total arsenic and arsenic (V). The characterization of arsenic was carried out by GFAAS using Pd as modifier. Optimization of the experimental conditions and instrumental parameters was investigated in detail. Recoveries of (90-110%) were obtained in the spiked samples. The detection limit was 0.2 microg l(-1). The proposed method was successfully applied for the determination of trace amount of arsenic (III) and arsenic (V) in process water samples. PMID:17761387

  4. Adsorption of molybdate on molybdate-imprinted chitosan/triethanolamine gel beads.

    PubMed

    Zhang, Liang; Xue, Juanqin; Zhou, Xingwen; Fei, Xiang; Wang, Yang; Zhou, Yuanzhen; Zhong, Lvling; Han, Xuanli

    2014-12-19

    Mo (VI)-imprinted chitosan (CTS)/triethanolamine (TEA) gel beads (Mo (VI)-ICTGBs) (ICTGBs=imprinted chitosan triethanolamine gel beads) were prepared by using ion-imprinted technology, in which TEA and molybdate solution were used in coagulation bath. The spectrum of FT-IR implies that bonding are formed between TEA and the primary hydroxyl of CTS, and ion gel reaction happen between CTS and molybdate; XRD patterns also prove the change among CTS, TEA and molybdate. SEM images and N2 adsorption show that the surface area increases obviously after eluting Mo (VI) ions. The adsorption isotherm of Mo (VI)-ICTGBs imply that the adsorption process is according with Freundlich model. Adsorption kinetics suggests that the pseudo-second order adsorption mechanism is predominant for this adsorbent system of Mo (VI)-ICTGBs. The Mo (VI)-ICTGBs show high adsorption capacity and good selectivity for Mo (VI) anions in the coexistence system at pH=6.0. The Mo (VI)-ICTGBs have a good application prospect, because it is with a simple and rapid technique and good durance. PMID:25263921

  5. Vanadate, molybdate and tungstate for orthomolecular medicine.

    PubMed

    Matsumoto, J

    1994-09-01

    Recent studies indicate that oxyanions, such as vanadate (V) or vanadyl (IV), cause insulin-like effects on rats by stimulating the insulin receptor tyrosine kinase. Tungstate (VI) and molybdate (VI) show the same effects on rat adipocytes and hepatocytes. Results of uncontrolled trials on volunteers accumulated in Japan also suggest that tungstate effectively regulates diabetes mellitus without detectable side effects. Since these oxyanions naturally exist in organisms, oxyanion therapy, the oral administration of vanadate, vanadyl, molybdate, or tungstate, can be considered to be orthomolecular medicine. Therefore, these oxyanions may provide a viable alternative to chemotherapy. Many diseases in addition to diabetes mellitus might also be treated since the implication of these results is that tyrosine kinases are involved in a variety of diseases. PMID:7815975

  6. Molybdate and molybdate/permanganate conversion coatings on Mg-8.5Li alloy

    NASA Astrophysics Data System (ADS)

    Wang, Guixiang; Zhang, Milin; Wu, Ruizhi

    2012-01-01

    A novel environment-friendly conversion coating for Mg-8.5Li alloy was obtained by immersing in a solution of molybdate. The concentration of ammonium molybdate and the addition of potassium permanganate were discussed in this experiment. The surface morphology of the conversion coatings was observed by scanning electron microscopy (SEM), and the chemical composition was investigated by X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). The corrosion resistance of Mg-8.5Li alloy and conversion coatings were investigated by means of potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and weight loss measurement. The results showed that the coatings with cracked morphology were homogeneous and uniform. The conversion coatings were mainly composed of metal-oxide as detected by XPS. The results of electrochemical measurement and weight loss measurement revealed that the molybdate conversion coating had better corrosion resistance than bare alloy and chromate conversion coating, and the molybdate/permanganate conversion coating had lower corrosion current density and higher coating resistance than the molybdate conversion coating.

  7. Removal of As(V), Cr(III) and Cr(VI) from aqueous environments by poly(acrylonitril-co-acrylamidopropyl-trimethyl ammonium chloride)-based hydrogels.

    PubMed

    Dudu, Tuba Ersen; Sahiner, Mehtap; Alpaslan, Duygu; Demirci, Sahin; Aktas, Nahit

    2015-09-15

    Cationic poly(Acrylonitril-co-Acrylamidopropyl-trimethyl Ammonium Chloride) (p(AN-co-APTMACl)) hydrogels in bulk were synthesized by using acrylonitrile (AN) and 3-acrylamidopropyl-trimethyl ammonium chloride (APTMACl) as monomers. The prepared hydrogels were exposed to amidoximation reaction to replace hydrophobic nitrile groups with hydrophilic amidoxime groups that have metal ion binding ability. Those replacements were increased the hydrogels absorption capacity for As(V) and Cr(VI). Langmuir and Freundlich isotherms equations were utilized to obtain the best-fitted isotherm model for the absorption of the ions at different metal ion concentrations. The absorption data of As(V) ion were fitted well to Freundlich isotherm while those of Cr(VI) and Cr(III) ions were fitted well to Langmuir isotherm. The maximum absorption of poly(3-acrylamidopropyl-trimethyl ammonium chloride (p(APTMACl)) and amid-p(AN-co-APTMACl) macro gels were 22.39 mg and 21.83 mg for As(V), and 30.65 mg and 18.16 mg for Cr(VI) ion per unit gram dried gel, respectively. Kinetically, the absorption behaviors of Cr(III) and Cr(VI) ions were fitted well to a pseudo 2nd-order kinetic model and those of As(V) ions were fitted well to a pseudo 1st order kinetic model. PMID:26188989

  8. Influence of ammonium availability on expression of nifD and amtB genes during biostimulation of a U(VI) contaminated aquifer: implications for U(VI) removal and monitoring the metabolic state of Geobacteraceae

    SciTech Connect

    Mouser, Paula J.; N'Guessan, A. Lucie; Elifantz, Hila; Holmes, Dawn E.; Williams, Kenneth H; Wilkins, Michael J.; Long, Philip E.; Lovley, Derek R.

    2009-03-25

    The influence of ammonium availability on bacterial community structure and the physiological status of Geobacter species during in situ bioremediation of uranium-contaminated groundwater was evaluated. Ammonium concentrations varied by 2 orders of magnitude (<4 to 400 ?M) across the study site. Analysis of 16S rRNA sequences suggested that ammonium may have been one factor influencing the community composition prior to acetate amendment with Rhodoferax species predominating over Geobacter species with higher ammonium and Dechloromonas species dominating at the site with lowest ammonium. However, once acetate was added and dissimilatory metal reduction was stimulated, Geobacter species became the predominant organisms at all locations. Rates of U(VI) reduction appeared to be more related to acetate concentrations rather than ammonium levels. In situ mRNA transcript abundance of the nitrogen fixation gene, nifD, and the ammonium transporter gene, amtB, in Geobacter species indicated that ammonium was the primary source of nitrogen during uranium reduction. The abundance of amtB was inversely correlated to ammonium levels, whereas nifD transcript levels were similar across all sites examined. These results suggest that nifD and amtB expression are closely regulated in response to ammonium availability to ensure an adequate supply of nitrogen while conserving cell resources. Thus, quantifying nifD and amtB transcript expression appears to be a useful approach for monitoring the nitrogen-related physiological status of subsurface Geobacter species. This study also emphasizes the need for more detailed analysis of geochemical and physiological interactions at the field scale in order to adequately model subsurface microbial processes during bioremediation.

  9. Selective sampling and measurement of Cr (VI) in water with polyquaternary ammonium salt as a binding agent in diffusive gradients in thin-films technique.

    PubMed

    Chen, Hong; Zhang, Yang-Yang; Zhong, Ke-Li; Guo, Lian-Wen; Gu, Jia-Li; Bo, Le; Zhang, Meng-Han; Li, Jian-Rong

    2014-04-30

    A diffusive gradients in thin films (DGT) device with polyquaternary ammonium salt (PQAS) as a novel binding agent (PQAS DGT) combined with graphite furnace atomic absorption spectrometry (GFAAS) was developed for the selective sampling and measurement of Cr (VI) in water. The performance of PQAS DGT was independent of pH 3-12 and ionic strength from 1 × 10(-3) to 1 molL(-1). DGT validation experiments showed that Cr (VI) was measured accurately as well as selectively by PQAS DGT, whereas Cr (III) was not determined quantitatively. Compared with diphenylcarbazide spectrophotometric method (DPC), the measurement of Cr (VI) with PQAS DGT was agreement with that of DPC method in the industrial wastewater. PQAS-DGT device had been successfully deployed in local freshwater. The concentrations of Cr (VI) determined by PQAS DGT coupled with GFAAS in Nuer River, Ling River and North Lake were 0.73 ± 0.09 μg L(-1), 0.50 ± 0.07 μg L(-1) and 0.61 ± 0.07 μg L(-1), respectively. The results indicate that PQAS DGT device can be used for the selective sampling and measurement Cr (VI) in water and its detection limit is lower than that of DPC method. PMID:24632368

  10. Comparative study of the synthesis of layered transition metal molybdates

    SciTech Connect

    Mitchell, S.; Gomez-Aviles, A.; Gardner, C.; Jones, W.

    2010-01-15

    Mixed metal oxides (MMOs) prepared by the mild thermal decomposition of layered double hydroxides (LDHs) differ in their reactivity on exposure to aqueous molybdate containing solutions. In this study, we investigate the reactivity of some T-Al containing MMOs (T=Co, Ni, Cu or Zn) towards the formation of layered transition metal molybdates (LTMs) possessing the general formula AT{sub 2}(OH)(MoO{sub 4}){sub 2}.H{sub 2}O, where A=NH{sub 4}{sup +}, Na{sup +} or K{sup +}. The phase selectivity of the reaction was studied with respect to the source of molybdate, the ratio of T to Mo and the reaction pH. LTMs were obtained on reaction of Cu-Al and Zn-Al containing MMOs with aqueous solutions of ammonium heptamolybdate. Rehydration of these oxides in the presence of sodium or potassium molybdate yielded a rehydrated LDH phase as the only crystalline product. The LTM products obtained by the rehydration of MMO precursors were compared with LTMs prepared by direct precipitation from the metal salts in order to study the influence of preparative route on their chemical and physical properties. Differences were noted in the composition, morphology and thermal properties of the resulting products. - Graphical abstract: Mixed metal oxides (MMOs) derived from layered double hydroxide precursors differ in their reactivity on exposure to aqueous molybdate containing solutions. We investigate the influence of the molybdate source, the rehydration pH and the ratio of T/Mo on the reactivity of some T-Al containing MMOs (T=Co, Ni, Cu or Zn) towards the formation of layered transition metal molybdates of general formula AT{sub 2}(OH)(MoO{sub 4}){sub 2}.H{sub 2}O (where A{sup +}=NH{sub 4}{sup +}, K{sup +} or Na{sup +}).

  11. Molybdate Reduction to Molybdenum Blue by an Antarctic Bacterium

    PubMed Central

    Ahmad, S. A.; Shukor, M. Y.; Shamaan, N. A.; Mac Cormack, W. P.; Syed, M. A.

    2013-01-01

    A molybdenum-reducing bacterium from Antarctica has been isolated. The bacterium converts sodium molybdate or Mo6+ to molybdenum blue (Mo-blue). Electron donors such as glucose, sucrose, fructose, and lactose supported molybdate reduction. Ammonium sulphate was the best nitrogen source for molybdate reduction. Optimal conditions for molybdate reduction were between 30 and 50 mM molybdate, between 15 and 20°C, and initial pH between 6.5 and 7.5. The Mo-blue produced had a unique absorption spectrum with a peak maximum at 865 nm and a shoulder at 710 nm. Respiratory inhibitors such as antimycin A, sodium azide, potassium cyanide, and rotenone failed to inhibit the reducing activity. The Mo-reducing enzyme was partially purified using ion exchange and gel filtration chromatography. The partially purified enzyme showed optimal pH and temperature for activity at 6.0 and 20°C, respectively. Metal ions such as cadmium, chromium, copper, silver, lead, and mercury caused more than 95% inhibition of the molybdenum-reducing activity at 0.1 mM. The isolate was tentatively identified as Pseudomonas sp. strain DRY1 based on partial 16s rDNA molecular phylogenetic assessment and the Biolog microbial identification system. The characteristics of this strain would make it very useful in bioremediation works in the polar and temperate countries. PMID:24381945

  12. Molybdate reduction to molybdenum blue by an Antarctic bacterium.

    PubMed

    Ahmad, S A; Shukor, M Y; Shamaan, N A; Mac Cormack, W P; Syed, M A

    2013-01-01

    A molybdenum-reducing bacterium from Antarctica has been isolated. The bacterium converts sodium molybdate or Mo⁶⁺ to molybdenum blue (Mo-blue). Electron donors such as glucose, sucrose, fructose, and lactose supported molybdate reduction. Ammonium sulphate was the best nitrogen source for molybdate reduction. Optimal conditions for molybdate reduction were between 30 and 50 mM molybdate, between 15 and 20°C, and initial pH between 6.5 and 7.5. The Mo-blue produced had a unique absorption spectrum with a peak maximum at 865 nm and a shoulder at 710 nm. Respiratory inhibitors such as antimycin A, sodium azide, potassium cyanide, and rotenone failed to inhibit the reducing activity. The Mo-reducing enzyme was partially purified using ion exchange and gel filtration chromatography. The partially purified enzyme showed optimal pH and temperature for activity at 6.0 and 20°C, respectively. Metal ions such as cadmium, chromium, copper, silver, lead, and mercury caused more than 95% inhibition of the molybdenum-reducing activity at 0.1 mM. The isolate was tentatively identified as Pseudomonas sp. strain DRY1 based on partial 16s rDNA molecular phylogenetic assessment and the Biolog microbial identification system. The characteristics of this strain would make it very useful in bioremediation works in the polar and temperate countries. PMID:24381945

  13. Heterogeneous photocatalytic reduction of Cr(VI) in UV-irradiated titania suspensions: Effect of protons, ammonium ions, and other interfacial aspects

    SciTech Connect

    Chenthamarakshan, C.R.; Rajeshwar, K.; Wolfrum, E.J.

    2000-03-21

    Heterogeneous photocatalytic reactions in UV-irradiated TiO{sub 2} suspensions are comprised of two conjugate reaction pathways involving the photogenerated electrons and holes, respectively. The role of the hole reaction pathway in the dynamics of the photocatalytic reduction of Cr(VI) is a major focus of this study. It is shown that proton supply plays a crucial role in this reduction reaction. Thus, the Cr(VI) photoreduction kinetics switch from first order to zero order as the proton concentration is systematically increased in the aqueous suspensions. Ammonium ions are also shown to exert a dramatic accelerating influence on Cr(VI) reduction in media of initial pH6. This new observation is rationalized by considering that these species act as hole scavengers. The consequent improvement in quantum yield combines with the facile proton generation upon NH{sub 4}{sup +} photooxidation, to result in the observed rate enhancement. Other interfacial aspects (i.e. adsorption) are also discussed.

  14. Adsorption of chromium(VI) from aqueous solutions by glycidylmethacrylate-grafted-densified cellulose with quaternary ammonium groups

    NASA Astrophysics Data System (ADS)

    Anirudhan, T. S.; Nima, J.; Divya, P. L.

    2013-08-01

    This study successfully synthesized a new adsorbent by ethylation of glycidylmethacrylate grafted aminated titanium dioxide densified cellulose (Et-AMPGDC), to remove chromium(VI) from aqueous solutions. The adsorbent was characterized by the FTIR, XRD, SEM and TG-DTG measurements. Batch adsorption technique using Et-AMPGDC was applied for the removal of Cr(VI) from aqueous solution and waste water. The contact time necessary to attain equilibrium and the optimum pH were found to be 1 h and 4.5, respectively. The kinetics of sorption of Cr(VI) ions was described by a pseudo-second-order kinetic model. The equilibrium isotherm data were analyzed using the Langmuir and Freundlich isotherm equations and the adsorption process was reflected by Langmuir isotherm. The maximum adsorption capacity was evaluated to be 123.60 mg/g. The electroplating industrial wastewater samples were treated with Et-AMPGDC to demonstrate its efficiency in removing Cr(VI) from wastewater. Almost complete removal was possible with 100 mg of the adsorbent from 50 mL of wastewater sample. Desorption efficiency was achieved by treatment with 0.1 M NaOH and five adsorption-desorption cycles were performed without significant decrease in adsorption capacity.

  15. Method for controlling corrosion using molybdate compositions

    SciTech Connect

    Boffardi, B.P.; Rey, S.P.

    1989-01-17

    A method is described for inhibiting corrosion in an aqueous system comprising adding to the system an effective amount of a corrosion inhibiting composition comprising: (a) a molybdate ion source; and (b) a water-soluble component selected from the group consisting of polymaleic anhydride; amine adducts of polymaleic anhydride; polymers prepared by polymerizing maleic anhydride with dimethyl diallyl ammonium chloride or homologs thereof; polymers prepared from 50-70%, by weight, acrylic acid or methacrylic acid, 10-40%, by weight, 2-acrylamido-2-methylpropyl sulfonic acid or 2-methyacrylamido-2-methylpropyl sulfonic acid and 10-30%, by weight, of a polyalkyleneoxide compound; salts of the above described polymers; phosphonates selected from the group consisting of 2-phosnphonobutane-1,2,4 tricarboxylic acid and hydroxyphosphono acetic acid; phosphino carboxylic acids; polyphosphoric acid and polyhydroxy esters of polyphosphoric acid; wherein the weight of (a):(b), on an active basis, ranges from about 10:1 to about 1:10.

  16. Comparative study of the synthesis of layered transition metal molybdates

    NASA Astrophysics Data System (ADS)

    Mitchell, S.; Gómez-Avilés, A.; Gardner, C.; Jones, W.

    2010-01-01

    Mixed metal oxides (MMOs) prepared by the mild thermal decomposition of layered double hydroxides (LDHs) differ in their reactivity on exposure to aqueous molybdate containing solutions. In this study, we investigate the reactivity of some T-Al containing MMOs ( T=Co, Ni, Cu or Zn) towards the formation of layered transition metal molybdates (LTMs) possessing the general formula AT2(OH)(MoO 4) 2·H 2O, where A=NH 4+, Na + or K +. The phase selectivity of the reaction was studied with respect to the source of molybdate, the ratio of T to Mo and the reaction pH. LTMs were obtained on reaction of Cu-Al and Zn-Al containing MMOs with aqueous solutions of ammonium heptamolybdate. Rehydration of these oxides in the presence of sodium or potassium molybdate yielded a rehydrated LDH phase as the only crystalline product. The LTM products obtained by the rehydration of MMO precursors were compared with LTMs prepared by direct precipitation from the metal salts in order to study the influence of preparative route on their chemical and physical properties. Differences were noted in the composition, morphology and thermal properties of the resulting products.

  17. Alkali-metal ion coordination in uranyl(VI) poly-peroxo complexes in solution, inorganic analogues to crown-ethers. Part 2. Complex formation in the tetramethyl ammonium-, Li(+)-, Na(+)- and K(+)-uranyl(VI)-peroxide-carbonate systems.

    PubMed

    Zanonato, Pier Luigi; Szabó, Zoltán; Vallet, Valerie; Di Bernardo, Plinio; Grenthe, Ingmar

    2015-10-01

    The constitution and equilibrium constants of ternary uranyl(vi) peroxide carbonate complexes [(UO2)p(O2)q(CO3)r](2(p-q-r)) have been determined at 0 °C in 0.50 M MNO3, M = Li, K, and TMA (tetramethyl ammonium), ionic media using potentiometric and spectrophotometric data; (17)O NMR data were used to determine the number of complexes present. The formation of cyclic oligomers, "[(UO2)(O2)(CO3)]n", n = 4, 5, 6, with different stoichiometries depending on the ionic medium used, suggests that Li(+), Na(+), K(+) and TMA ions act as templates for the formation of uranyl peroxide rings where the uranyl-units are linked by μ-η(2)-η(2) bridged peroxide-ions. The templating effect is due to the coordination of the M(+)-ions to the uranyl oxygen atoms, where the coordination of Li(+) results in the formation of Li[(UO2)(O2)(CO3)]4(7-), Na(+) and K(+) in the formation of Na/K[(UO2)(O2)(CO3)]5(9-) complexes, while the large tetramethyl ammonium ion promotes the formation of two oligomers, TMA[(UO2)(O2)(CO3)]5(9-) and TMA[(UO2)(O2)(CO3)]6(11-). The NMR spectra demonstrate that the coordination of Na(+) in the five- and six-membered oligomers is significantly stronger than that of TMA(+); these observations suggest that the templating effect is similar to the one observed in the synthesis of crown-ethers. The NMR experiments also demonstrate that the exchange between TMA[(UO2)(O2)(CO3)]5(9-) and TMA[(UO2)(O2)(CO3)]6(11-) is slow on the (17)O chemical shift time-scale, while the exchange between TMA[(UO2)(O2)(CO3)]6(11-) and Na[(UO2)(O2)(CO3)]6(11-) is fast. There was no indication of the presence of large clusters of the type identified by Burns and Nyman (M. Nyman and P. C. Burns, Chem. Soc. Rev., 2012, 41, 7314-7367) and possible reasons for this and the implications for the synthesis of large clusters are briefly discussed. PMID:26331776

  18. An Arabidopsis thaliana high-affinity molybdate transporter required for efficient uptake of molybdate from soil

    PubMed Central

    Tomatsu, Hajime; Takano, Junpei; Takahashi, Hideki; Watanabe-Takahashi, Akiko; Shibagaki, Nakako; Fujiwara, Toru

    2007-01-01

    Molybdenum (Mo) is a trace element essential for living organisms, however no molybdate transporter has been identified in eukaryotes. Here, we report the identification of a molybdate transporter, MOT1, from Arabidopsis thaliana. MOT1 is expressed in both roots and shoots, and the MOT1 protein is localized, in part, to plasma membranes and to vesicles. MOT1 is required for efficient uptake and translocation of molybdate and for normal growth under conditions of limited molybdate supply. Kinetics studies in yeast revealed that the Km value of MOT1 for molybdate is ≈20 nM. Furthermore, Mo uptake by MOT1 in yeast was not affected by coexistent sulfate, and MOT1 did not complement a sulfate transporter-deficient yeast mutant strain. These data confirmed that MOT1 is specific for molybdate and that the high affinity of MOT1 allows plants to obtain scarce Mo from soil. PMID:18003916

  19. Complex peroxyuranates. Synthesis and structural assessment of alkali-metal and ammonium dioxoperoxy(sulfato)aquouranates(VI), A/sub 2/(UO/sub 2/(O/sub 2/)SO/sub 4/(H/sub 2/O)) (A = NH/sub 4/, Na), and alkali-metal and ammonium dioxoperoxy(oxalato)uranate(VI) hydrates, A/sub 2/(UO/sub 2/(O/sub 2/)C/sub 2/O/sub 4/). H/sub 2/O

    SciTech Connect

    Bhattacharjee, M.; Chaudhuri, M.K.; Purkayastha, R.N.D.

    1986-07-02

    Yellow microcrystalline alkali-metal and ammonium dioxoperoxy(sulfato)aquouranates(VI), A/sub 2/(UO/sub 2/(O/sub 2/)SO/sub 4/(H/sub 2/O)) (A = NH/sub 4/, Na), and alkali-metal and ammonium dioxoperoxy(oxalato)uranate(VI) hydrates, A/sub 2/(UO/sub 2/(O/sub 2/)C/sub 2/O/sub 4/).H/sub 2/O (A = NH/sub 4/, Na, K), have been synthesized from the reaction of the product obtained by treating an aqueous solution of UO/sub 2/(NO/sub 3/)/sub 2/.6H/sub 2/O with alkali-metal or ammonium hydroxide, AOH, with 30% H/sub 2/O/sub 2/ and aqueous sulfuric acid and oxalic acid solution, respectively, in the mole ratio UO/sub 2/(NO/sub 3/)/sub 2/.6H/sub 2/O:H/sub 2/O/sub 2/:SO/sub 4//sup 2 -/ or C/sub 2/O/sub 4//sup 2 -/ of 1:111:5 or 1, at pH 6 maintained by the addition of the corresponding alkali-metal or ammonium hydroxide. Precipitation was completed by the addition of ethanol. IR and laser Raman spectra suggest that the O/sub 2//sup 2 -/ and SO/sub 4//sup 2 -/ ions in (UO/sub 2/(O/sub 2/)SO/sub 4/(H/sub 2/O))/sup 2 -/ are bonded to the UO/sub 2//sup 2 +/ center in a bridging and in a monodentate manner, respectively, while both the O/sub 2//sup 2 -/ and C/sub 2/O/sub 4//sup 2 -/ ions in (UO/sub 2/(O/sub 2/)C/sub 2/O/sub 4/)/sup 2 -/ bind the uranyl center in bidentate chelated fashion. The complex peroxyuranates are diamagnetic and insoluble. The A/sub 2/(UO/sub 2/(O/sub 2/)SO/sub 4/(H/sub 2/O)) compounds, unlike A/sub 2/(UO/sub 2/(O/sub 2/)C/sub 2/O/sub 4/).H/sub 2/O, are stable up to 110 /sup 0/C. Whereas H/sub 2/O in A/sub 2/(UO/sub 2/(O/sub 2/SO/sub 4/(H/sub 2/O)) is coordinated to the UO/sub 2//sup 2 +/ center, it occurs as a water of crystallization in the corresponding peroxy oxalato compounds. 20 references, 3 tables.

  20. Molybdate Coatings for Protecting Aluminum Against Corrosion

    NASA Technical Reports Server (NTRS)

    Calle, Luz Marina; MacDowell, Louis G.

    2005-01-01

    Conversion coatings that comprise mixtures of molybdates and several additives have been subjected to a variety of tests to evaluate their effectiveness in protecting aluminum and alloys of aluminum against corrosion. Molybdate conversion coatings are under consideration as replacements for chromate conversion coatings, which have been used for more than 70 years. The chromate coatings are highly effective in protecting aluminum and its alloys against corrosion but are also toxic and carcinogenic. Hexavalent molybdenum and, hence, molybdates containing hexavalent molybdenum, have received attention recently as replacements for chromates because molybdates mimic chromates in a variety of applications but exhibit significantly lower toxicity. The tests were performed on six proprietary formulations of molybdate conversion coatings, denoted formulations A through F, on panels of aluminum alloy 2024-T3. A bare alloy panel was also included in the tests. The tests included electrochemical impedance spectroscopy (EIS), measurements of corrosion potentials, scanning electron microscopy (SEM) with energy-dispersive spectroscopy (EDS), and x-ray photoelectron spectroscopy (XPS).

  1. Crystal structure of the heptamolybdate(VI) (paramolybdate) ion, [Mo7O24]6-, in the ammonium and potassium tetrahydrate salts

    USGS Publications Warehouse

    Evans, H.T., Jr.; Gatehouse, B.M.; Leverett, P.

    1975-01-01

    The crystal structures of the isomorphous salts MI6 [Mo7O24],4H2O (M = NH4 or K) have been refined by three-dimensional X-ray diffraction methods. Unit cell dimensions of these monoclinic compounds, space group P21/C with Z = 4, are, ammonium salt: a = 8.3934 ?? 0.0008, b = 36.1703 ?? 0.0045, c = 10.4715 ?? 0.0011 A??, ?? = 115.958?? ?? 0.008??; and potassium salt: a = 8.15 ?? 0.02, b = 35.68 ?? 0.1, c = 10.30 ?? 0.02 A??, ?? = 115.2?? ?? 02??. By use of multiple Weissenberg patterns, 8197 intensity data (Mo-K?? radiation) for the ammonium compound and 2178 (Cu-K?? radiation) for the potassium compound were estimated visually and used to test and refine Lindqvist's proposed structure in the space group P21/c. Lindqvist's structure was confirmed and the full matrix least-squares isotropic refinement led to R 0.076 (ammonium) 0.120 (potassium), with direct unambiguous location of the cations and water molecules in the potassium compound.

  2. Acquisition and Role of Molybdate in Pseudomonas aeruginosa

    PubMed Central

    Pederick, Victoria G.; Eijkelkamp, Bart A.; Ween, Miranda P.; Begg, Stephanie L.; Paton, James C.

    2014-01-01

    In microaerophilic or anaerobic environments, Pseudomonas aeruginosa utilizes nitrate reduction for energy production, a process dependent on the availability of the oxyanionic form of molybdenum, molybdate (MoO42−). Here, we show that molybdate acquisition in P. aeruginosa occurs via a high-affinity ATP-binding cassette permease (ModABC). ModA is a cluster D-III solute binding protein capable of interacting with molybdate or tungstate oxyanions. Deletion of the modA gene reduces cellular molybdate concentrations and results in inhibition of anaerobic growth and nitrate reduction. Further, we show that conditions that permit nitrate reduction also cause inhibition of biofilm formation and an alteration in fatty acid composition of P. aeruginosa. Collectively, these data highlight the importance of molybdate for anaerobic growth of P. aeruginosa and reveal novel consequences of nitrate reduction on biofilm formation and cell membrane composition. PMID:25172858

  3. Acquisition and role of molybdate in Pseudomonas aeruginosa.

    PubMed

    Pederick, Victoria G; Eijkelkamp, Bart A; Ween, Miranda P; Begg, Stephanie L; Paton, James C; McDevitt, Christopher A

    2014-11-01

    In microaerophilic or anaerobic environments, Pseudomonas aeruginosa utilizes nitrate reduction for energy production, a process dependent on the availability of the oxyanionic form of molybdenum, molybdate (MoO4 (2-)). Here, we show that molybdate acquisition in P. aeruginosa occurs via a high-affinity ATP-binding cassette permease (ModABC). ModA is a cluster D-III solute binding protein capable of interacting with molybdate or tungstate oxyanions. Deletion of the modA gene reduces cellular molybdate concentrations and results in inhibition of anaerobic growth and nitrate reduction. Further, we show that conditions that permit nitrate reduction also cause inhibition of biofilm formation and an alteration in fatty acid composition of P. aeruginosa. Collectively, these data highlight the importance of molybdate for anaerobic growth of P. aeruginosa and reveal novel consequences of nitrate reduction on biofilm formation and cell membrane composition. PMID:25172858

  4. Facile chemical synthesis and structure characterization of copper molybdate nanoparticles

    NASA Astrophysics Data System (ADS)

    Rahimi-Nasrabadi, Mehdi; Pourmortazavi, Seied Mahdi; Khalilian-Shalamzari, Morteza

    2015-03-01

    Experimental parameters of a synthesis route were optimized by Taguchi robust design for the facile and controllable synthesis of copper molybdate nanoparticles. CuMoO4 nanoparticles were synthesized by chemical precipitation followed by hydrothermal process. Effects of different parameters of synthesis procedure, i.e. concentrations of both reagents, copper feeding flow rate and temperature of reactor on the particle size of prepared copper molybdate nanoparticles were investigated. The results of statistical optimization revealed that the size of copper molybdate particles is dependent on the procedure variables involving copper concentrations, flow rate and temperature of the reactor; while, molybdate concentration has a no considerable role in determining the size of CuMoO4 particles. Based on the results obtained by statistical optimization process, the nanoparticles of copper molybdate were prepared and then their structure and chemical composition were characterized by various techniques, i.e. SEM, TEM, XRD, EDX, FT-IR, UV-Vis and photoluminescence spectroscopy.

  5. Light deflection in gadolinium molybdate ferroelastic crystals

    NASA Astrophysics Data System (ADS)

    Staniorowski, Piotr; Bornarel, Jean

    2000-02-01

    The deflection of a He-Ne light beam by polydomain gadolinium molybdate (GMO) crystals has been studied with respect to incidence angle icons/Journals/Common/alpha" ALT="alpha" ALIGN="TOP"/> i on the sample at room temperature. The A and B deflected beams do not cross each other during the icons/Journals/Common/alpha" ALT="alpha" ALIGN="TOP"/> i variation, in contrast to results and calculations previously published. The model using the Fresnel equation confirms this result. The model presented is more accurate for numerical calculation than that using the Huygens construction.

  6. Simultaneous speciation analysis of chromate, molybdate, tungstate and vanadate in welding fume alkaline extracts by HPLC-ICP-MS.

    PubMed

    Ščančar, Janez; Berlinger, Balázs; Thomassen, Yngvar; Milačič, Radmila

    2015-09-01

    CRM 545, Cr(VI) in welding dust loaded on a filter. Good agreement between determined and reported certified values was obtained. For molybdate, tungstate and vanadate the assessment of accuracy was performed by spiking welding fume filters. Good recoveries for all investigated species (98-101%) confirmed the accuracy of the analytical procedure. PMID:26003707

  7. Ammonium acetate

    Integrated Risk Information System (IRIS)

    Ammonium acetate ; CASRN 631 - 61 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic

  8. Ammonium methacrylate

    Integrated Risk Information System (IRIS)

    Ammonium methacrylate ; CASRN 16325 - 47 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcin

  9. Ammonium sulfamate

    Integrated Risk Information System (IRIS)

    Ammonium sulfamate ; CASRN 7773 - 06 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogen

  10. Molybdate adsorption from steel slag eluates by subsoils.

    PubMed

    Matern, K; Rennert, T; Mansfeldt, T

    2013-11-01

    Steel slags are industrial by-products which are generated in large amounts worldwide, e.g. 150-230×10(6) Mg in 2012, and which are partly used for construction. Molybdenum (Mo) can be added during steel processing in order to harden the steel. The objective of this study was to evaluate the adsorption behaviour of molybdate (MoO4(2-)) from slag eluates in subsoils. Molybdate batch adsorption experiments were carried out with eluates obtained from two different kinds of steel slags (i) LD slag (Linz-Donawitz operation, LDS) and (ii) electric arc furnace slag (EAF) to assess the risk that may arise from the contamination of groundwater by the leaching of molybdate. Six different subsoils were chosen in order to provide a wide range of chemical properties (pH 4.0-7.6; dithionite-extractable Fe 0.73-14.7 g kg(-1)). Molybdate adsorption experiments were carried out at the pH of the steel slag eluates (pH 11-12) as well as at pH values adjusted to the soil pH. The data were evaluated with the Freundlich equation. Molybdate adsorption exhibited a maximum near pH 4 for steel slag eluates adjusted to the soil pH, and decreased rapidly with increasing pH until adsorption was virtually zero at pH>11. Adsorption was greater for soils with high amounts of dithionite-extractable Fe oxides. The extent and behaviour of molybdate adsorption from both eluates was similar. After a reaction time of 24h, the pH of the EAF slag eluate was lower than that of the LD steel slag eluate, which was caused by different acid buffer capacities. Some soils were able to decrease the pH of the EAF slag eluates by about 4 pH units, enhancing the adsorption of molybdate. Transport simulations indicated that molybdate discharge is low in acidic soils. PMID:23973286

  11. Statistical optimization of synthesis procedure and characterization of europium (III) molybdate nano-plates

    NASA Astrophysics Data System (ADS)

    Pourmortazavi, Seied Mahdi; Rahimi-Nasrabadi, Mehdi; Fazli, Yousef; Mohammad-Zadeh, Mohammad

    2015-06-01

    Europium (III) molybdate nano-plates were synthesized in this work via chemical precipitation route involving adding of europium (III) ion solution to the aqueous solution of molybdate reagent. Effects of some reaction variables such as concentrations of europium and molybdate ions, flow rate of europium reagent, and reactor temperature on the diameter of the synthesized europium (III) molybdate nano-plates were experimentally investigated by orthogonal array design. The results showed that the size of europium (III) molybdate nano-plates can be optimized by adjusting the concentrations of europium (III) and molybdate ions, as well as the reactional temperature. Europium (III) molybdate nano-plates prepared under the optimum conditions were characterized by X-ray powder diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy.

  12. On the effective ionic radii for ammonium.

    PubMed

    Sidey, Vasyl

    2016-08-01

    A set of effective ionic radii corresponding to different coordination numbers (CNs) and compatible with the radii system by Shannon [Acta Cryst. (1976), A32, 751-767] has been derived for ammonium: 1.40 Å (CN = IV), 1.48 Å (CN = VI), 1.54 Å (CN = VIII) and 1.67 Å (CN = XII). The bond-valence parameters r0 = 2.3433 Å and B = 0.262 Å have been determined for ammonium-fluorine bonds. PMID:27484382

  13. From yellow to black: dramatic changes between cerium(IV) and plutonium(IV) molybdates.

    PubMed

    Cross, Justin N; Duncan, Patrick M; Villa, Eric M; Polinski, Matthew J; Babo, Jean-Marie; Alekseev, Evgeny V; Booth, Corwin H; Albrecht-Schmitt, Thomas E

    2013-02-20

    Hydrothermal reactions of CeCl(3) and PuCl(3) with MoO(3) and Cs(2)CO(3) yield surprisingly different results. Ce(3)Mo(6)O(24)(H(2)O)(4) crystallizes as bright yellow plates (space group C2/c, a = 12.7337(7) Å, b = 22.1309(16) Å, c = 7.8392(4) Å, β = 96.591(4)°, V = 2194.6(2) Å(3)), whereas CsPu(3)Mo(6)O(24)(H(2)O) crystallizes as semiconducting black-red plates (space group C2/c, a = 12.633(5) Å, b = 21.770(8) Å, c = 7.743(7) Å, β = 96.218(2)°, V = 2117(2) Å(3)). The topologies of the two compounds are similar, with channel structures built from disordered Mo(VI) square pyramids and (RE)O(8) square antiprisms (RE = Ce(IV), Pu(IV)). However, the Pu(IV) compound contains Cs(+) in its channels, while the channels in Ce(3)Mo(6)O(24)(H(2)O)(4) contain water molecules. Disorder and an ambiguous oxidation state of Mo lead to the formula CsPu(3)Mo(6)O(24)(H(2)O), where one Mo site is Mo(V) and the rest are Mo(VI). X-ray absorption near-edge structure (XANES) experiments were performed to investigate the source of the black color of CsPu(3)Mo(6)O(24)(H(2)O). These experiments revealed Pu to be tetravalent, while the strong pre-edge absorption from the distorted molybdate anions leaves the oxidation state ambiguous between Mo(V) and Mo(VI). PMID:23360299

  14. One-step synthesis of bismuth molybdate catalysts via flame spray pyrolysis for the selective oxidation of propylene to acrolein.

    PubMed

    Schuh, K; Kleist, W; Høj, M; Trouillet, V; Jensen, A D; Grunwaldt, J-D

    2014-12-18

    Flame spray pyrolysis (FSP) of Bi(III)- and Mo(VI)-2-ethylhexanoate dissolved in xylene resulted in various nanocrystalline bismuth molybdate phases depending on the Bi/Mo ratio. Besides α-Bi2Mo3O12 and γ-Bi2MoO6, FSP gave direct access to the metastable β-Bi2Mo2O9 phase with high surface area (19 m(2) g(-1)). This phase is normally only obtained at high calcination temperatures (>560 °C) resulting in lower surface areas. The β-phase was stable up to 400 °C and showed superior catalytic performance compared to α- and γ-phases in selective oxidation of propylene to acrolein at temperatures relevant for industrial applications (360 °C). PMID:25350295

  15. Catalytic oxidation of propylene--7. Use of temperature programmed reoxidation to characterize. gamma. -bismuth molybdate

    SciTech Connect

    Uda, T.; Lin, T.T.; Keulks, G.W.

    1980-03-01

    Temperature-programed reoxidation of propylene-reduced ..gamma..-Bi/sub 2/MoO/sub 6/ revealed a low-temperature peak (LTP) at 158/sup 0/C and a high-temperature peak (HTP) at 340/sup 0/C. Auger spectroscopy and X-ray diffraction of reduced and partially or completely reoxidized bismuth molybdate showed that at the LTP, molybdenum(IV) is oxidized to molybdenum(VI) and bismuth, from the metallic state to an oxidation state between zero and three, and that the HTP is associated with the complete oxidation of bismuth to bismuth(III). Activity tests for propylene oxidation showed lower acrolein formation on the catalyst, on which only the LTP was reoxidized than on catalysts on which both peaks were reoxidized. The reoxidation kinetics of the catalyst under conditions corresponding to the LTP showed an activation energy of 22.9 kcal/mole below 170/sup 0/C and near zero above 170/sup 0/C; the break in the Arrhenius plot of reoxidation of the catalyst under conditions corresponding to the HTP was at 400/sup 0/C, with activation energies of 46 kcal/mole at lower and near zero at higher temperatures. Propylene oxidation was apparently rate-limited by the HTP reoxidation process below 400/sup 0/C and by allylic hydrogen abstraction above 400/sup 0/C.

  16. Poly[di­ammonium [di­aqua­(μ7-benzene-1,2,3,4,5,6-hexa­carboxyl­ato)tetra­oxido­diuranium(VI)

    PubMed Central

    Cantos, Paula M.; Cahill, Christopher L.

    2014-01-01

    Uranyl-carboxyl­ate hybrid materials dominate the catalog of uranyl compounds owing in part to the affinity between COO− functional groups and UO2 2+. Polycarboxyl­ate organic ligands may present a degree of steric hindrance and could thus influence the resulting uranyl topology. Single crystals of the title compound, {(NH4)2[(UO2)2(C12O12)(H2O)2]}n, were synthesized hydro­thermally as a result of reacting uranyl nitrate with benzene-1,2,3,4,5,6-hexa­carb­oxy­lic acid (mellitic acid). The structure is comprised of a single unique monomeric uranyl cation adopting a penta­gonal bipyramidal geometry. The uranyl coordination sphere is composed of four O atoms originating from one half of a fully deprotonated mellitic acid ligand and a single water mol­ecule. The observed axial U—O bonds display an average distance of 1.765 (8) Å, whereas equatorial O atoms are found at an average distance of 2.40 (5) Å. All uranium–oxygen bond lengths are in good agreement with literature values. Furthermore, the coordin­ation between the uranyl penta­gonal bipyramids and the mellitic acid anion constructs a three-dimensional anionic framework which is charge-balanced with ammonium cations. Additional stabilization of the structure is provided by O—H⋯O and N—H⋯O hydrogen bonding inter­actions between the components. PMID:24826103

  17. Corrosion study of stainless steel SS304L in molten molybdates

    NASA Astrophysics Data System (ADS)

    Usami, T.; Uruga, K.; Tsukada, T.; Miura, Y.; Komamine, S.; Ochi, E.

    2016-04-01

    Depending on operating conditions of the vitrification process of high-level liquid waste, molten salt mainly composed of sodium and molybdenum can be generated, and poured into stainless steel canisters. In this work, the possible reaction between the molten molybdate and stainless steel was investigated using multi-component molybdate and simple Na2MoO4 - MoO3 molybdate. In the experiments using multi-component molybdates, no significant reaction is observed between the mixed molybdates and the stainless steel specimens at 700 °C in 4 h. The reaction rate of the stainless steel with the multi-component molybdate increases in proportion to exp(-1/T). The depth of the most reacted area is about 300 μm even at 1000 °C, and was much smaller than the 6 mm thickness of the canister. In the simple Na2MoO4 - MoO3 molybdate, the reaction rate was proportional to the MoO3 concentration. The essence of the reaction is oxidation of metals by Mo6+ - > Mo4+. Part of the reaction product mainly composed of Fe is dissolved into the molybdate, while the other part mainly composed of Cr sloughs and forms a banded layer.

  18. Lithium vanado(V)molybdate(VI), Li[VMoO6

    PubMed Central

    Ezzine Yahmed, Safa; Nasri, Rawia; Zid, Mohamed Faouzi; Driss, Ahmed

    2013-01-01

    Brannerite-type Li[VMoO6] has been synthesized by a solid state reaction route. The V and Mo atoms statistically occupy the same site with mirror symmetry and are octa­hedrally surrounded by O atoms. The framework is two-dimensional and is built up from edge-sharing (V,Mo)O6 octa­hedra forming (VMoO6)∞ layers that run parallel to the (001) plane. Li+ ions are situated in position with symmetry 2/m in the inter­layer space. The bond-valence analysis reveals that the Li+ ionic conductivity is along the [010] and [110] directions, and shows that this material may have inter­esting conduction properties. This simulation proposes a model of the lithium conduction pathways. PMID:24426977

  19. Dielectric and conducting behaviour of polycrystalline holmium octa-molybdate

    NASA Astrophysics Data System (ADS)

    Want, Basharat; Zahoor Ahmad, Bhat; Bhat, Bilal Hamid

    2014-09-01

    Polycrystalline holmium octa-molybdate spherulites have been obtained by using gel diffusion technique and characterized by different physio-chemical techniques. The surfaces of these spherulites are composed of nano-rod with an average diameter of about 80 nm. At room temperature the initial crystal structure is triclinic, space group P1. Thermal studies suggested a phase transition occurring in holmium octa-molybdate crystals at about 793 K. The electrical properties of the system have been studied as a function of frequency and temperature in the ranges of 20 Hz-3 MHz and 290-570 K, respectively. A giant dielectric constant and two loss peaks have been observed in the permittivity formalism. The conducting behaviour of the material is also discussed. The conductivity was found to be 1572 μ Ω-1 m-1 at room temperature and 3 MHz frequency. The conductivity of the polycrystalline material was attributed to the fact that it arises due to the migration of defects on the oxygen sub-lattice. Impedance studies were also performed in the frequency domain to infer the bulk and grain boundary contributions to the overall electric response of the material. The electrical responses have been attributed to the grain, grain-boundary, and interfacial effects.

  20. Role of Molybdate and Other Transition Metals in the Accumulation of Protochelin by Azotobacter vinelandii

    PubMed Central

    Cornish, Anthony S.; Page, William J.

    2000-01-01

    Both molybdate and iron are metals that are required by the obligately aerobic organism Azotobacter vinelandii to survive in the nutrient-limited conditions of its natural soil environment. Previous studies have shown that a high concentration of molybdate (1 mM) affects the formation of A. vinelandii siderophores such that the tricatecholate protochelin is formed to the exclusion of the other catecholate siderophores, azotochelin and aminochelin. It has been shown previously that molybdate combines readily with catecholates and interferes with siderophore function. In this study, we found that the manner in which each catecholate siderophore interacted with molybdate was consistent with the structure and binding potential of the siderophore. The affinity that each siderophore had for molybdate was high enough that stable molybdo-siderophore complexes were formed but low enough that the complexes were readily destabilized by Fe3+. Thus, competition between Fe3+ and molybdate did not appear to be the primary cause of protochelin accumulation; in addition, we determined that protochelin accumulated in the presence of vanadate, tungstate, Zn2+, and Mn2+. We found that all five of these metal ions partially inhibited uptake of 55Fe-protochelin and 55Fe-azotochelin complexes. Also, each of these metal ions partially inhibited the activity of ferric reductase, an enzyme important in the deferration of ferric siderophores. Our results suggest that protochelin accumulates in the presence of molybdate because protochelin uptake and conversion into its component parts, azotochelin and aminochelin, are inhibited by interference with ferric reductase. PMID:10742245

  1. Ammonium nitrate explosive systems

    SciTech Connect

    Coburn, M.D.; Stinecipher, M.M.

    1981-11-17

    Novel explosives which comprise mixtures of ammonium nitrate and an ammonium salt of a nitroazole in desired ratios are disclosed. A preferred nitroazole is 3,5-dinitro-1,2,4-triazole. The explosive and physical properties of these explosives may readily be varied by the addition of other explosives and oxidizers. Certain of these mixtures have been found to act as ideal explosives.

  2. Ammonium nitrate explosive systems

    DOEpatents

    Stinecipher, Mary M.; Coburn, Michael D.

    1981-01-01

    Novel explosives which comprise mixtures of ammonium nitrate and an ammonium salt of a nitroazole in desired ratios are disclosed. A preferred nitroazole is 3,5-dinitro-1,2,4-triazole. The explosive and physical properties of these explosives may readily be varied by the addition of other explosives and oxidizers. Certain of these mixtures have been found to act as ideal explosives.

  3. The structures and properties of the new two-dimensional inorganic–organic hybrid materials based on the molybdate chains

    SciTech Connect

    Li, Na; Mu, Bao; Cao, Xinyu; Huang, Rudan

    2014-09-15

    A series of inorganic organic hybrid materials based on polyoxometalates(POMs), namely, [M{sup II}(HL){sub 2}(H{sub 2}O){sub 2}][Mo{sup VI}{sub 6}O{sub 20}] [M=Co (1), Ni (2), Cu (3), Zn (4)], [Mn{sup IV}L{sub 2}(H{sub 2}O){sub 2}][Mo{sup VI}{sub 6}O{sub 20}] (5), and (HL){sub 3}PMO{sub 12}O{sub 40} (6) [L=3-(4-pyridyl)pyrazole], have been synthesized. The compounds have been characterized by elemental analysis, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction. The results from single-crystal X-ray diffraction indicate that 1–5 are isostructural. It is worth noting that the polyanions are bridged by Mo–O–Mo to form 1D inorganic chains, which are further connected via M ions to form 2D nets. In compound 6, the ligands are used as the positive ions to balance the charge of the compound. Moreover, the magnetic properties of compound 5 have also been investigated in detail. - Graphical abstract: In complex 1, The Co ion is six coordinated by four oxygen atoms from two Mo{sub 6}O{sub 20} and two water molecules, and two N atoms from two different ligand. It is noticeable that there is an one-dimensional chain molybdate, which is combined by O–Mo–O, then the chain parallel with each other, the Mo{sub 6} anion acts as a bidentate ligand providing O7 atoms to bridge CoII ions to form a 2D inorganic layer. Finally every nets become 3D structure by hydrogen bond. - Highlights: • Novel inorganic–organic hybrid materials have been prepared. • Compounds 1–5 contain the 1D molybdate chains composed of (MoO{sub 6}) octahedra. • The 1D chains parallel with each other to form a 2D inorganic layer.

  4. Changes in metabolic pathways of Desulfovibrio alaskensis G20 cells induced by molybdate excess.

    PubMed

    Nair, Rashmi R; Silveira, Célia M; Diniz, Mário S; Almeida, Maria G; Moura, Jose J G; Rivas, Maria G

    2015-03-01

    The activity of sulfate-reducing bacteria (SRB) intensifies the problems associated to corrosion of metals and the solution entails significant economic costs. Although molybdate can be used to control the negative effects of these organisms, the mechanisms triggered in the cells exposed to Mo-excess are poorly understood. In this work, the effects of molybdate ions on the growth and morphology of the SRB Desulfovibrio alaskensis G20 (DaG20) were investigated. In addition, the cellular localization, ion uptake and regulation of protein expression were studied. We found that molybdate concentrations ranging between 50 and 150 µM produce a twofold increase in the doubling time with this effect being more significant at 200 µM molybdate (five times increase in the doubling time). It was also observed that 500 µM molybdate completely inhibits the cellular growth. On the context of protein regulation, we found that several enzymes involved in energy metabolism, cellular division and metal uptake processes were particularly influenced under the conditions tested. An overall description of some of the mechanisms involved in the DaG20 adaptation to molybdate-stress conditions is discussed. PMID:25488518

  5. Reduction of molybdate to molybdenum blue by Enterobacter sp. strain Dr.Y13.

    PubMed

    Shukor, M Y; Rahman, M F; Shamaan, N A; Syed, M A

    2009-09-01

    Extensive use of metals in various industrial applications has caused substantial environmental pollution. Molybdenum-reducing bacteria isolated from soils can be used to remove molybdenum from contaminated environments. In this work we have isolated a local bacterium with the capability to reduce soluble molybdate to the insoluble molybdenum blue. We studied several factors that would optimize molybdate reduction. Electron donor sources such as glucose, sucrose, lactose, maltose and fructose (in decreasing efficiency) supported molybdate reduction after 24 h of incubation with optimum glucose concentration for molybdate reduction at 1.5% (w/v). The optimum pH, phosphate and molybdate concentrations, and temperature for molybdate reduction were pH 6.5, 5.0, 25 to 50 mM and 37 degrees C, respectively. The Mo-blue produced by cellular reduction exhibited a unique absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. Metal ions such as chromium, cadmium, copper, silver and mercury caused approximately 73, 71, 81, 77 and 78% inhibition of the molybdenum-reducing activity, respectively. All of the respiratory inhibitors tested namely rotenone, azide, cyanide and antimycin A did not show any inhibition to the molybdenum-reducing activity suggesting components of the electron transport system are not responsible for the reducing activity. The isolate was tentatively identified as Enterobacter sp. strain Dr.Y13 based on carbon utilization profiles using Biolog GN plates and partial 16S rDNA molecular phylogeny. PMID:19455513

  6. Infrared band intensities in ammonium hydroxide and ammonium salts

    NASA Technical Reports Server (NTRS)

    Sethna, P. P.; Downing, H. D.; Pinkley, L. W.; Williams, D.

    1978-01-01

    We have applied Kramers-Kronig analysis to reflection spectra to determine the optical constants of ammonium hydroxide and of aqueous solutions of ammonium chloride and bromide. From considerations of the absorption indices k(nu) we conclude that ammonium hydroxide consists of a solution of NH3 in water, in which NH3 molecules are hydrogen bonded to neighboring water molecules. The spectrum of ammonium hydroxide differs from the spectra of ammonium salts, in which bands characteristic of NH4(+) ions are prominent. The existence of ammonium hydroxide as an aerosol in planetary atmospheres is briefly discussed

  7. Mechanistic studies on the reactions of molybdenum(VI), tungsten(VI), vanadium(V), and arsenic(V) tetraoxo anions with the Fe{sup II}Fe{sup III} form of purple acid phosphatase from porcine uteri (Uteroferrin)

    SciTech Connect

    Lim, J.S.; Aquino, M.A.S.; Skyes, A.G.

    1996-01-31

    The Fe{sup II}-Fe{sup III} form of purple acid phosphatase (PAP{sub r}) from porcine uteri (uteroferrin) catalyses the hydrolysis of phosphate esters. Here, kinetic studies have been extended to include the complexing of tetraoxo XO{sub 4} anions of molybdate(VI), tungstate(VI), vanadate(V), and arsenate(V) with PAP{sub r}. UV-vis absorbance changes are small and the range of concentrations is restricted by the need to maximise monomer XO{sub 4} forms. Rate constants k{sub obs}(25{degrees}C) were determined by stopped-flow monitoring of the reactions at {approximately}520 nm.

  8. 70. INTERIOR VIEW OF AMMONIUM NITRATE HOUSE, LOOKING AT AMMONIUM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    70. INTERIOR VIEW OF AMMONIUM NITRATE HOUSE, LOOKING AT AMMONIUM NITRATE IN STORAGE. APRIL 18, 1919. - United States Nitrate Plant No. 2, Reservation Road, Muscle Shoals, Muscle Shoals, Colbert County, AL

  9. Glufosinate-ammonium

    Integrated Risk Information System (IRIS)

    Glufosinate - ammonium ; CASRN 77182 - 82 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarci

  10. Structural and spectral investigation of terbium molybdate nanophosphor.

    PubMed

    Mani, Kamal P; Vimal, G; Biju, P R; Joseph, Cyriac; Unnikrishnan, N V; Ittyachen, M A

    2015-09-01

    Terbium molybdate nanophosphors were synthesized through a facile sol-gel route. The structure of the phosphors was characterized by X-ray diffraction, Raman spectra and Fourier transform infrared spectroscopy analysis. The X-ray diffraction studies revealed that the structure of the nanophosphor gradually changes from monoclinic to orthorhombic phase as heated from 700 to 900 °C. High resolution transmission electron microscopy, SAED and EDS were also employed to characterize the size, crystallinity and composition of the samples. Detailed spectroscopic investigations were carried out by Judd-Ofelt analysis based on UV-Visible-NIR absorption and emission spectra. The luminescence spectra suggest that phosphors with orthorhombic structure have better luminescence properties than the monoclinic structure. The phosphors showed intense green emission under near-UV excitation due to the energy transfer from the host lattice to Tb(3+) ions. The CIE coordinates suggest enhanced color purity for green emission and short fluorescence decay values proposes the suitability for LED applications. These phosphors can be applied as promising candidates for blue and near-UV excited WLEDs. PMID:25919330

  11. Directed synthesis of noncentrosymmetric molybdates using composition space analysis.

    PubMed

    Veltman, Thomas R; Stover, Adam K; Narducci Sarjeant, Amy; Ok, Kang Min; Halasyamani, P Shiv; Norquist, Alexander J

    2006-07-10

    A systematic investigation of the factors governing the reaction product composition, hydrogen bonding, and symmetry was conducted in the MoO3/3-aminoquinuclidine/H2O system. Composition space analysis was performed through 36 individual reactions under mild hydrothermal conditions using racemic 3-aminoquinuclidine. Single crystals of three new compounds, [C7H16N2][Mo3O10] x H2O, [C7H16N2]2[Mo8O26] x H2O, and [C7H16N2]2[Mo8O26] x 4 H2O, were grown. The relative phase stabilities for these products are dependent upon the reactant mole fractions in the initial reaction gel. This phase stability information was used to direct the synthesis of two new noncentrosymmetric compounds, using either (S)-(-)-3-aminoquinuclidine dihydrochloride or (R)-(+)-3-aminoquinuclidine dihydrochloride. [(R)-C7H16N2]2[Mo8O26] and [(S)-C7H16N2]2[Mo8O26] both crystallize in the noncentrosymmetric space group P2(1) (No. 4), which has the polar crystal class 2 (C2). The second-harmonic generation activities were measured on sieved powders. The structure-directing properties of the molybdate components in each compound were determined using bond valence sums. The structures of all five compounds were determined using single-crystal X-ray diffraction. PMID:16813416

  12. Structural and spectral investigation of terbium molybdate nanophosphor

    NASA Astrophysics Data System (ADS)

    Mani, Kamal P.; Vimal, G.; Biju, P. R.; Joseph, Cyriac; Unnikrishnan, N. V.; Ittyachen, M. A.

    2015-09-01

    Terbium molybdate nanophosphors were synthesized through a facile sol-gel route. The structure of the phosphors was characterized by X-ray diffraction, Raman spectra and Fourier transform infrared spectroscopy analysis. The X-ray diffraction studies revealed that the structure of the nanophosphor gradually changes from monoclinic to orthorhombic phase as heated from 700 to 900 °C. High resolution transmission electron microscopy, SAED and EDS were also employed to characterize the size, crystallinity and composition of the samples. Detailed spectroscopic investigations were carried out by Judd-Ofelt analysis based on UV-Visible-NIR absorption and emission spectra. The luminescence spectra suggest that phosphors with orthorhombic structure have better luminescence properties than the monoclinic structure. The phosphors showed intense green emission under near-UV excitation due to the energy transfer from the host lattice to Tb3+ ions. The CIE coordinates suggest enhanced color purity for green emission and short fluorescence decay values proposes the suitability for LED applications. These phosphors can be applied as promising candidates for blue and near-UV excited WLEDs.

  13. Classification of a Haemophilus influenzae ABC transporter HI1470/71 through its cognate molybdate periplasmic binding protein, MolA.

    PubMed

    Tirado-Lee, Leidamarie; Lee, Allen; Rees, Douglas C; Pinkett, Heather W

    2011-11-01

    molA (HI1472) from H. influenzae encodes a periplasmic binding protein (PBP) that delivers substrate to the ABC transporter MolB(2)C(2) (formerly HI1470/71). The structures of MolA with molybdate and tungstate in the binding pocket were solved to 1.6 and 1.7 Å resolution, respectively. The MolA-binding protein binds molybdate and tungstate, but not other oxyanions such as sulfate and phosphate, making it the first class III molybdate-binding protein structurally solved. The ∼100 μM binding affinity for tungstate and molybdate is significantly lower than observed for the class II ModA molybdate-binding proteins that have nanomolar to low micromolar affinity for molybdate. The presence of two molybdate loci in H. influenzae suggests multiple transport systems for one substrate, with molABC constituting a low-affinity molybdate locus. PMID:22078568

  14. Classification of a Haemophilus influenzae ABC Transporter HI1470/71 through Its Cognate Molybdate Periplasmic Binding Protein, MolA

    SciTech Connect

    Tirado-Lee, Leidamarie; Lee, Allen; Rees, Douglas C.; Pinkett, Heather W.

    2014-10-02

    molA (HI1472) from H. influenzae encodes a periplasmic binding protein (PBP) that delivers substrate to the ABC transporter MolB{sub 2}C{sub 2} (formerly HI1470/71). The structures of MolA with molybdate and tungstate in the binding pocket were solved to 1.6 and 1.7 {angstrom} resolution, respectively. The MolA-binding protein binds molybdate and tungstate, but not other oxyanions such as sulfate and phosphate, making it the first class III molybdate-binding protein structurally solved. The {approx}100 {mu}M binding affinity for tungstate and molybdate is significantly lower than observed for the class II ModA molybdate-binding proteins that have nanomolar to low micromolar affinity for molybdate. The presence of two molybdate loci in H. influenzae suggests multiple transport systems for one substrate, with molABC constituting a low-affinity molybdate locus.

  15. Removal of molybdate from water by adsorption onto ZnCl2 activated coir pith carbon.

    PubMed

    Namasivayam, C; Sangeetha, D

    2006-07-01

    Removal and recovery of molybdate from aqueous solution was investigated using ZnCl2 activated carbon developed from coir pith. Studies were conducted to delineate the effects of contact time, adsorbent dose, molybdate concentration, pH and temperature. Two theoretical adsorption isotherms, namely, Langmuir and Freundlich were used to describe the experimental results. The Langmuir adsorption capacity (Q0) was found to be 18.9 mg molybdate/g of the adsorbent. Adsorption followed second order kinetics. Studies were performed at different pH values to find out the pH at which maximum adsorption occurred. The pH effect and desorption studies showed that ion exchange and chemisorption mechanism were involved in the adsorption process. Thermodynamic parameters such as DeltaG0, DeltaH0 and DeltaS0 for the adsorption were evaluated. Effect of foreign ions on adsorption of molybdate has been examined. The results showed that ZnCl2 activated coir pith carbon was effective for the removal and recovery of molybdate from water. PMID:16006123

  16. Sub-1 nm Nickel Molybdate Nanowires as Building Blocks of Flexible Paper and Electrochemical Catalyst for Water Oxidation.

    PubMed

    Liu, Huiling; Li, Haoyi; He, Peilei; Wang, Xun

    2016-02-24

    Sub-1 nm, extremely long nickel molybdate nanowires are synthesized based on a good/poor solvent system. The ultrathin nanowires can be hierarchically assembled into flexible, free-standing films with good mechanical properties. Compared with the large-size counterpart, nickel molybdate ultrathin nanowires display promising oxygen evolution reaction catalytic performance derived from the ultrathin feature. PMID:26724910

  17. Cranial mononeuropathy VI

    MedlinePlus

    ... Abducens palsy; Lateral rectus palsy; Vith nerve palsy; Cranial nerve VI palsy ... mononeuropathy VI is damage to the sixth cranial (skull) nerve. This nerve, also called the abducens nerve, helps ...

  18. Cranial mononeuropathy VI

    MedlinePlus

    Abducens paralysis; Abducens palsy; Lateral rectus palsy; Vith nerve palsy; Cranial nerve VI palsy ... VI is damage to the sixth cranial (skull) nerve. This nerve, also called the abducens nerve, helps ...

  19. Optical filtering and luminescence property of some molybdates prepared by combustion synthesis

    SciTech Connect

    Yadav, P. J.; Joshi, C. P.; Moharil, S. V.

    2014-10-15

    As an important class of lanthanide inorganic compounds, rare earth ions doped molybdates have gained much attention due to their attractive luminescence and structural properties, supporting various promising applications as phosphor materials in the fields such as white light-emitting diodes, optical fibers, biolabel, lasers, and so on. The molybdate family has promising trivalent cation conducting properties and most of the optical properties result from electron transitions of the 4f shell, which are greatly affected by the composition and structures of rare-earth compounds. In this paper we report the molybdate CaMoO{sub 4}:Eu{sup 3+} for red SSL and Bi{sub 1.4}Y{sub 0.6}MoO{sub 6}, Y{sub 6}MoO{sub 12} for optical filtering, prepared by one step combustion synthesis.

  20. Synthesis and investigation of uranyl molybdate UO2MoO4

    NASA Astrophysics Data System (ADS)

    Nagai, Takayuki; Sato, Nobuaki; Kitawaki, Shin-ichi; Uehara, Akihiro; Fujii, Toshiyuki; Yamana, Hajimu; Myochin, Munetaka

    2013-02-01

    In order to examine easily synthetic conditions of uranyl molybdate, UO2MoO4, used for the reprocessing process study of spent nuclear oxide fuels in alkaline molybdate melts, the uranium molybdate compounds were produced from U3O8 powder and anhydrous MoO3 reagent. The results of having investigated them in solid state by using X-ray diffractometry and Raman spectrometry, it was confirmed that UO2MoO4 could be synthesized by heating mixed powder of U3O8 and MoO3 with stoichiometric mole ratio at 770 °C for 4 h under air atmosphere. Moreover, adding this UO2MoO4 into Li2MoO4sbnd Na2MoO4 eutectic melt, most of the dissolved uranium species in the melt were observed as hexa-valent uranyl ions by absorption spectrophotometry.

  1. Metal molybdate nanorods as non-precious electrocatalysts for the oxygen reduction

    NASA Astrophysics Data System (ADS)

    Wu, Tian; Zhang, Lieyu

    2015-12-01

    Development of non-precious electrocatalysts with applicable electrocatalytic activity towards the oxygen reduction reaction (ORR) is important to fulfill broad-based and large-scale applications of metal/air batteries and fuel cells. Herein, nickel and cobalt molybdates with uniform nanorod morphology are synthesized using a facile one-pot hydrothermal method. The ORR activity of the prepared metal molybdate nanorods in alkaline media are investigated by using cyclic voltammetry (CV), linear sweep voltammetry (LSV) and chronoamperomety in rotating disk electrode (RDE) techniques. The present study suggests that the prepared metal molybdate nanorods exhibit applicable electrocatalytic activities towards the ORR in alkaline media, promising the applications as non-precious cathode in fuel cells and metal-air batteries.

  2. Behavior of silver molybdate at high-pressure

    SciTech Connect

    Arora, A.K.; Nithya, R.; Misra, Sunasira; Yagi, Takehiko

    2012-12-15

    Behavior of cubic spinel phase of Ag{sub 2}MoO{sub 4} is investigated at high pressure using X-ray diffraction and Raman spectroscopy. The P-V data are fitted to a third order Birch-Murnaghan equation of state using a value of B{sub 0}=113 GPa and B Prime {sub 0}=4. The compound is also found to exhibit a phase transition around 5 GPa to a tetragonal structure and the two phases are found to coexist over a range of pressures. Raman spectra exhibit dramatic changes across the phase transition. Increase of X-ray background scattering and broadening of the Raman peaks associated with MoO{sub 4} tetrahedral ions in the high pressure phase suggest evolution of positional disorder. However, no evidence of pressure-induced amorphization was found up to 47 GPa. - Graphical abstract: Evolution of the integrated intensity of all the diffraction peaks between 12 and 18 degree 2{theta} as a function of pressure. The rapid decrease of the intensity suggests evolution of positional disorder in the high-pressure tetragonal phase. Highlights: Black-Right-Pointing-Pointer First in-situ X-ray diffraction and Raman study of cubic silver molybdate at high pressure. Black-Right-Pointing-Pointer Commencement of a structural transition to a tetragonal phase is found at 2.3 GPa. Black-Right-Pointing-Pointer The high-pressure phase is found to have positional disorder. Black-Right-Pointing-Pointer A bulk modulus of 113 GPa is obtained from the equation of state.

  3. Mo enrichment in black shale and reduction of molybdate by sulfate-reducing bacteria (SRB) (Invited)

    NASA Astrophysics Data System (ADS)

    Xu, H.; Barton, L. L.

    2010-12-01

    The Lower Cambrian Black shale in Zunyi area of Guizhou Province, Southern China contains significant amount of Mo, As, and sulfide minerals. Additionally, Mo and sulfides are closely associated with organic matter of kerogen. Transmission electron microscopy (TEM) results show pyrite micro-crystals and Mo-As-S-bearing carbon (kerogen). High-resolution TEM image shows that Mo-rich areas are Mo-sulfide (molybdenite) layers that form poorly crystalline structures in organic carbon matrix. X-ray energy-dispersive spectra (EDS) indicate composition from the pyrite and the Mo-rich area. The black shale is very unique because of its high Mo concentration. One possible mechanism for enriching Mo from paleo-seawater is the involvement of SRB. Molybdate is an essential trace element required by biological systems including the anaerobic sulfate-reducing bacteria (SRB); however, detrimental consequences may occur if molybdate is present in high concentrations in the environment. We followed the growth of Desulfovibrio gigas ATCC 19364, D. vulgaris Hildenborough, D. desulfuricans DSM 642, and D. desulfuricans DSM 27774 in media containing sub-lethal levels of molybdate and observed a red-brown color in the culture fluid. Spectral analysis of the culture fluid revealed absorption peaks at 467 nm, 395 nm and 314 nm and this color is proposed to be a molybdate-sulfide complex. Reduction of molybdate with the formation of molybdate disulfide occurs in the periplasm D. gigas and D. desulfuricans DSM 642. From these results we suggest that the occurrence of poorly crystalline Mo-sulfides in black shale may be a result from SRB reduction and selective enrichment of Mo in paleo-seawater. We suggest that similar SRB mechanism could cause the Mo enrichment in a ~ 2.5 billion years old late Archean McRae Shale, which is related to the great oxidation event of early earth atmosphere.

  4. The Molybdate-Responsive Escherichia coli ModE Transcriptional Regulator Coordinates Periplasmic Nitrate Reductase (napFDAGHBC) Operon Expression with Nitrate and Molybdate Availability

    PubMed Central

    McNicholas, Paul M.; Gunsalus, Robert P.

    2002-01-01

    Expression of the Escherichia coli napFDAGHBC operon (also known as aeg46.5), which encodes the periplasmic molybdoenzyme for nitrate reduction, is increased in response to anaerobiosis and further stimulated by the addition of nitrate or to a lesser extent by nitrite to the cell culture medium. These changes are mediated by the transcription factors Fnr and NarP, respectively. Utilizing a napF-lacZ operon fusion, we demonstrate that napF gene expression is impaired in strain defective for the molybdate-responsive ModE transcription factor. This control abrogates nitrate- or nitrite-dependent induction during anaerobiosis. Gel shift and DNase I footprinting analyses establish that ModE binds to the napF promoter with an apparent Kd of about 35 nM at a position centered at −133.5 relative to the start of napF transcription. Although the ModE binding site sequence is similar to other E. coli ModE binding sites, the location is atypical, because it is not centered near the start of transcription. Introduction of point mutations in the ModE recognition site severely reduced or abolished ModE binding in vitro and conferred a modE phenotype (i.e., loss of molybdate-responsive gene expression) in vivo. In contrast, deletion of the upstream ModE region site rendered napF expression independent of modE. These findings indicate the involvement of an additional transcription factor to help coordinate nitrate- and molybdate-dependent napF expression by the Fnr, NarP, NarL, and ModE proteins. The upstream ModE regulatory site functions to override nitrate control of napF gene expression when the essential enzyme component, molybdate, is limiting in the cell environment. PMID:12029041

  5. Hydrothermal synthesis of ammonium illite

    USGS Publications Warehouse

    Sucha, V.; Elsass, F.; Eberl, D.D.; Kuchta, L'.; Madejova, J.; Gates, W.P.; Komadel, P.

    1998-01-01

    Synthetic gel and glass of illitic composition, natural kaolinite, and mixed-layer illite-smectite were used as starting materials for hydrothermal synthesis of ammonium illite. Ammonium illite was prepared from synthetic gel by hydrothermal treatment at 300??C. The onset of crystallization began within 3 h, and well-crystallized ammonium illite appeared at 24 h. Increasing reaction time (up to four weeks) led to many illite layers per crystal. In the presence of equivalent proportions of potassium and ammonium, the gel was transformed to illite with equimolar contents of K and NH4. In contrast, synthesis using glass under the same conditions resulted in a mixture of mixed-layer ammonium illite-smectite with large expandability and discrete illite. Hydrothermal treatments of the fine fractions of natural kaolinite and illite-smectite produced ammonium illite from kaolinite but the illite-smectite remained unchanged.

  6. Ammonium diphosphitoindate(III)

    PubMed Central

    Hamchaoui, Farida; Rebbah, Houria; Le Fur, Eric

    2013-01-01

    The crystal structure of the title compound, NH4[In(HPO3)2], is built up from InIII cations (site symmetry 3m.) adopting an octa­hedral environment and two different phosphite anions (each with site symmetry 3m.) exhibiting a triangular–pyramidal geometry. Each InO6 octa­hedron shares its six apices with hydrogen phosphite groups. Reciprocally, each HPO3 group shares all its O atoms with three different metal cations, leading to [In(HPO3)2]− layers which propagate in the ab plane. The ammonium cation likewise has site symmetry 3m.. In the structure, the cations are located between the [In(HPO3)2]− layers of the host framework. The sheets are held together by hydrogen bonds formed between the NH4 + cations and the O atoms of the framework. PMID:23633983

  7. Ammonium diphosphitoindate(III).

    PubMed

    Hamchaoui, Farida; Rebbah, Houria; Le Fur, Eric

    2013-04-01

    The crystal structure of the title compound, NH4[In(HPO3)2], is built up from In(III) cations (site symmetry 3m.) adopting an octa-hedral environment and two different phosphite anions (each with site symmetry 3m.) exhibiting a triangular-pyramidal geometry. Each InO6 octa-hedron shares its six apices with hydrogen phosphite groups. Reciprocally, each HPO3 group shares all its O atoms with three different metal cations, leading to [In(HPO3)2](-) layers which propagate in the ab plane. The ammonium cation likewise has site symmetry 3m.. In the structure, the cations are located between the [In(HPO3)2](-) layers of the host framework. The sheets are held together by hydrogen bonds formed between the NH4 (+) cations and the O atoms of the framework. PMID:23633983

  8. Influence of heterogeneous ammonium availability on bacterial community structure and the expression of nitrogen fixation and ammonium transporter genes during in situ bioremediation of uranium-contaminated groundwater

    SciTech Connect

    Mouser, P.J.; N'Guessan, A.L.; Elifantz, H.; Holmes, D.E.; Williams, K.H.; Wilkins, M.J.; Long, P.E.; Lovley, D.R.

    2009-04-01

    The impact of ammonium availability on microbial community structure and the physiological status and activity of Geobacter species during in situ bioremediation of uranium-contaminated groundwater was evaluated. Ammonium concentrations varied by as much as two orders of magnitude (<4 to 400 {micro}M) across the study site. Analysis of 16S rRNA gene sequences suggested that ammonium influenced the composition of the microbial community prior to acetate addition with Rhodoferax species predominating over Geobacter species at the site with the highest ammonium, and Dechloromonas species dominating at sites with lowest ammonium. However, once acetate was added, and dissimilatory metal reduction was stimulated, Geobacter species became the predominant organisms at all locations. Rates of U(VI) reduction appeared to be more related to the concentration of acetate that was delivered to each location rather than the amount of ammonium available in the groundwater. In situ mRNA transcript abundance of the nitrogen fixation gene, nifD, and the ammonium importer gene, amtB, in Geobacter species indicated that ammonium was the primary source of nitrogen during in situ uranium reduction, and that the abundance of amtB transcripts was inversely correlated to ammonium levels across all sites examined. These results suggest that nifD and amtB expression by subsurface Geobacter species are closely regulated in response to ammonium availability to ensure an adequate supply of nitrogen while conserving cell resources. Thus, quantifying nifD and amtB expression appears to be a useful approach for monitoring the nitrogen-related physiological status of Geobacter species in subsurface environments during bioremediation. This study also emphasizes the need for more detailed analysis of geochemical/physiological interactions at the field scale, in order to adequately model subsurface microbial processes.

  9. Development of an exchange assay for cytosolic glucocorticoid receptors using the synergistic effects of molybdate plus dithiothreitol

    SciTech Connect

    Kalimi, M.; Hubbard, J.R.

    1983-09-01

    A glucocorticoid receptor exchange assay has been developed for the accurate quantification of both free and steroid-bound receptors in rat liver cytosol. Hepatic cytosol from adrenalectomized rats was saturated in vitro with unlabeled corticosterone. Cytosol was subsequently treated with (/sup 3/H)dexamethasone (with and without 1000-fold cold dexamethasone) for 2-28 h at 4 C in the presence of 10 mM molybdate plus 5 mM dithiothreitol (DTT). Complete exchange occurred between 16-28 h in the presence of molybdate plus DTT. In control and 10 mM molybdate (alone) treated samples only about 50% exchange was achieved. In the presence of 5 mM DTT (alone) approximately 60-70% exchange was observed. The exchange assay (utilizing molybdate plus DTT) was also applied to hepatic cytosol of adrenalectomized rats injected with corticosterone in vivo and to samples prebound with unlabeled dexamethasone.

  10. Multiplicity of Sulfate and Molybdate Transporters and Their Role in Nitrogen Fixation in Rhizobium leguminosarum bv. viciae Rlv3841.

    PubMed

    Cheng, Guojun; Karunakaran, Ramakrishnan; East, Alison K; Poole, Philip S

    2016-02-01

    Rhizobium leguminosarum Rlv3841 contains at least three sulfate transporters, i.e., SulABCD, SulP1 and SulP2, and a single molybdate transporter, ModABC. SulABCD is a high-affinity transporter whose mutation prevented growth on a limiting sulfate concentration, while SulP1 and SulP2 appear to be low-affinity sulfate transporters. ModABC is the sole high-affinity molybdate transport system and is essential for growth with NO3(-) as a nitrogen source on limiting levels of molybdate (<0.25 μM). However, at 2.5 μM molybdate, a quadruple mutant with all four transporters inactivated, had the longest lag phase on NO3(-), suggesting these systems all make some contribution to molybdate transport. Growth of Rlv3841 on limiting levels of sulfate increased sulB, sulP1, modB, and sulP2 expression 313.3-, 114.7-, 6.2-, and 4.0-fold, respectively, while molybdate starvation increased only modB expression (three- to 7.5-fold). When grown in high-sulfate but not low-sulfate medium, pea plants inoculated with LMB695 (modB) reduced acetylene at only 14% of the wild-type rate, and this was not further reduced in the quadruple mutant. Overall, while modB is crucial to nitrogen fixation at limiting molybdate levels in the presence of sulfate, there is an unidentified molybdate transporter also capable of sulfate transport. PMID:26812045

  11. The surface of iron molybdate catalysts used for the selective oxidation of methanol

    NASA Astrophysics Data System (ADS)

    Yeo, Benjamin R.; Pudge, Geoffrey J. F.; Bugler, Keith G.; Rushby, Alice V.; Kondrat, Simon; Bartley, Jonathan; Golunski, Stanislaw; Taylor, Stuart H.; Gibson, Emma; Wells, Peter. P.; Brookes, Catherine; Bowker, Michael; Hutchings, Graham J.

    2016-06-01

    The oxidation of methanol to formaldehyde is a major chemical process carried out catalytically and iron molybdate is one of the major catalysts for this process. In this paper we explore the nature of the active and selective surfaces of iron molybdate catalysts and show that the effective catalysts comprise molybdenum rich surfaces. We conclude that it is therefore important to maximise the surface area of these active catalysts and to this end we have studied catalysts made using a new physical grinding method with oxalic acid. For super-stoichiometric materials (Fe:Mo = 1:2.2) the reaction data show that physical mixing produces effective catalysts, possibly offering an improvement over the conventional co-precipitation method.

  12. Effect of chlorate, molybdate, and shikimic acid on Salmonella Typhimurium in aerobic and anaerobic cultures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two studies were conducted to examine the effects of shikimic acid (60 µg/mL) and(or) molybdate (1 mM) on the sensitivity of Salmonella enterica serovar Typhimurium to sodium chlorate (5 mM) during anaerobic (90% N2:5% CO2:5% H2) or aerobic growth in brain heart infusion broth supplemented with 5 mM...

  13. Effect of solid-phase amorphization on the spectral characteristics of europium-doped gadolinium molybdate

    NASA Astrophysics Data System (ADS)

    Shmurak, S. Z.; Kiselev, A. P.; Kurmasheva, D. M.; Red'Kin, B. S.; Sinitsyn, V. V.

    2010-05-01

    A method is proposed for detecting spectral characteristics of optically inactive molybdates of rare-earth elements by their doping with rare-earth ions whose luminescence lies in the transparency region of all structural modifications of the sample. Gadolinium molybdate is chosen as the object of investigations, while europium ions are used as an optically active and structurally sensitive admixture. It is shown that after the action of a high pressure under which gadolinium molybdate passes to the amorphous state, the spectral characteristics of Gd1.99Eu0.01(MoO4)3 (GMO:Eu) change radically; namely, considerable line broadening is observed in the luminescence spectra and the luminescence excitation spectra, while the long-wave threshold of optical absorption is shifted considerably (by approximately 1.1 eV) towards lower energies. It is found that by changing the structural state of GMO:Eu by solid-state amorphization followed by annealing, the spectral characteristics of the sample can be purposefully changed. This is extremely important for solving the urgent problem of designing high-efficiency light-emitting diodes producing “white” light.

  14. Ultrasensitive Visual Sensing of Molybdate Based on Enzymatic-like Etching of Gold Nanorods.

    PubMed

    Zhang, Zhiyang; Chen, Zhaopeng; Chen, Lingxin

    2015-08-25

    Here, we have developed a novel approach to the visual detection of molybdate with high sensitivity and selectivity in aqueous media based on the combination of catalytic formation of iodine and iodine-mediated etching of gold nanorods. In weak acid solution, like peroxidase, molybdate can catalyze the reaction between H2O2 and I(-) to produce I2, a moderate oxidant, which then etches gold nanorods preferentially along the longitudinal direction in the presence of hexadecyltrimethylammonium bromide. The etching results in the longitudinal localized surface plasmon resonance extinction peak shifts to short wavelength, accompanied by a color change from blue to red. Under optimal conditions, this sensor exhibits good sensitivity with a detection limit of 1.0 nM. The approach is highlighted by its high selectivity and tolerance to interference, which enables the sensor to detect molybdate directly in real samples, such as tap water, drinking water, and seawater. In addition, perhaps the proposed sensing strategy can be also used for other targets that can selectively regulate the formation of I2 under given conditions. PMID:26226196

  15. A Rhodobacter capsulatus Member of a Universal Permease Family Imports Molybdate and Other Oxyanions▿

    PubMed Central

    Gisin, Jonathan; Müller, Alexandra; Pfänder, Yvonne; Leimkühler, Silke; Narberhaus, Franz; Masepohl, Bernd

    2010-01-01

    Molybdenum (Mo) is an important trace element that is toxic at high concentrations. To resolve the mechanisms underlying Mo toxicity, Rhodobacter capsulatus mutants tolerant to high Mo concentrations were isolated by random transposon Tn5 mutagenesis. The insertion sites of six independent isolates mapped within the same gene predicted to code for a permease of unknown function located in the cytoplasmic membrane. During growth under Mo-replete conditions, the wild-type strain accumulated considerably more Mo than the permease mutant. For mutants defective for the permease, the high-affinity molybdate importer ModABC, or both transporters, in vivo Mo-dependent nitrogenase (Mo-nitrogenase) activities at different Mo concentrations suggested that ModABC and the permease import molybdate in nanomolar and micromolar ranges, respectively. Like the permease mutants, a mutant defective for ATP sulfurylase tolerated high Mo concentrations, suggesting that ATP sulfurylase is the main target of Mo inhibition in R. capsulatus. Sulfate-dependent growth of a double mutant defective for the permease and the high-affinity sulfate importer CysTWA was reduced compared to those of the single mutants, implying that the permease plays an important role in sulfate uptake. In addition, permease mutants tolerated higher tungstate and vanadate concentrations than the wild type, suggesting that the permease acts as a general oxyanion importer. We propose to call this permease PerO (for oxyanion permease). It is the first reported bacterial molybdate transporter outside the ABC transporter family. PMID:20851900

  16. Tungstate, a Molybdate Analog Inactivating Nitrate Reductase, Deregulates the Expression of the Nitrate Reductase Structural Gene

    PubMed Central

    Deng, Mingde; Moureaux, Thérèse; Caboche, Michel

    1989-01-01

    Nitrate reductase (NR, EC 1.6.6.1) from higher plants is a homodimeric enzyme carrying a molybdenum cofactor at the catalytic site. Tungsten can be substituted for molybdenum in the cofactor structure, resulting in an inactive enzyme. When nitratefed Nicotiana tabacum plants were grown on a nutrient solution in which tungstate was substituted for molybdate, NR activity in the leaves decreased to a very low level within 24 hours while NR protein accumulated progressively to a level severalfold higher than the control after 6 days. NR mRNA level in molybdate-grown plants exhibited a considerable day-night fluctuation. However, when plants were treated with tungstate, NR mRNA level remained very high. NR activity and protein increased over a 24-hour period when nitrate was added back to N-starved molybdate-grown plants. NR mRNA level increased markedly during the first 2 hours and then decreased. In the presence of tungstate, however, the induction of NR activity by nitrate was totally abolished while high levels of NR protein and mRNA were both induced, and the high level of NR mRNA was maintained over a 10-hour period. These results suggest that the substitution of tungsten for molybdenum in NR complex leads to an overexpression of the NR structural gene. Possible mechanisms involved in this deregulation are discussed. Images Figure 2 Figure 3 Figure 5 PMID:16667015

  17. High performance ammonium nitrate propellant

    NASA Technical Reports Server (NTRS)

    Anderson, F. A. (Inventor)

    1979-01-01

    A high performance propellant having greatly reduced hydrogen chloride emission is presented. It is comprised of: (1) a minor amount of hydrocarbon binder (10-15%), (2) at least 85% solids including ammonium nitrate as the primary oxidizer (about 40% to 70%), (3) a significant amount (5-25%) powdered metal fuel, such as aluminum, (4) a small amount (5-25%) of ammonium perchlorate as a supplementary oxidizer, and (5) optionally a small amount (0-20%) of a nitramine.

  18. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... GRAS § 184.1138 Ammonium chloride. (a) Ammonium chloride (NH4Cl, CAS Reg. No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Ammonium chloride. 184.1138 Section 184.1138...

  19. 21 CFR 184.1143 - Ammonium sulfate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ammonium sulfate. 184.1143 Section 184.1143 Food... Specific Substances Affirmed as GRAS § 184.1143 Ammonium sulfate. (a) Ammonium sulfate ((NH4)2SO4, CAS Reg... is prepared by the neutralization of sulfuric acid with ammonium hydroxide. (b) The ingredient...

  20. 21 CFR 184.1137 - Ammonium carbonate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...). It is prepared by the sublimation of a mixture of ammonium sulfate and calcium carbonate and occurs... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ammonium carbonate. 184.1137 Section 184.1137 Food... Specific Substances Affirmed as GRAS § 184.1137 Ammonium carbonate. (a) Ammonium carbonate ((NH4)2CO3,...

  1. 21 CFR 184.1143 - Ammonium sulfate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Ammonium sulfate. 184.1143 Section 184.1143 Food... GRAS § 184.1143 Ammonium sulfate. (a) Ammonium sulfate ((NH4)2SO4, CAS Reg. No. 7783-20-2) occurs... neutralization of sulfuric acid with ammonium hydroxide. (b) The ingredient meets the specifications of the...

  2. 21 CFR 184.1143 - Ammonium sulfate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ammonium sulfate. 184.1143 Section 184.1143 Food... Specific Substances Affirmed as GRAS § 184.1143 Ammonium sulfate. (a) Ammonium sulfate ((NH4)2SO4, CAS Reg... is prepared by the neutralization of sulfuric acid with ammonium hydroxide. (b) The ingredient...

  3. 21 CFR 184.1137 - Ammonium carbonate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...). It is prepared by the sublimation of a mixture of ammonium sulfate and calcium carbonate and occurs... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ammonium carbonate. 184.1137 Section 184.1137 Food... Specific Substances Affirmed as GRAS § 184.1137 Ammonium carbonate. (a) Ammonium carbonate ((NH4)2CO3,...

  4. Solubility of the Sodium and Ammonium Salts of Oxalic Acid in Water with Ammonium Sulfate.

    PubMed

    Buttke, Lukas G; Schueller, Justin R; Pearson, Christian S; Beyer, Keith D

    2016-08-18

    The solubility of the sodium and ammonium salts of oxalic acid in water with ammonium sulfate present has been studied using differential scanning calorimetry, X-ray crystallography, and infrared spectroscopy. The crystals that form from aqueous mixtures of ammonium sulfate/sodium hydrogen oxalate were determined to be sodium hydrogen oxalate monohydrate under low ammonium sulfate conditions and ammonium hydrogen oxalate hemihydrate under high ammonium sulfate conditions. Crystals from aqueous mixtures of ammonium sulfate/sodium oxalate were determined to be ammonium oxalate monohydrate under moderate to high ammonium sulfate concentrations and sodium oxalate under low ammonium sulfate concentrations. It was also found that ammonium sulfate enhances the solubility of the sodium oxalate salts (salting in effect) and decreases the solubility of the ammonium oxalate salts (salting out effect). In addition, a partial phase diagram for the ammonium hydrogen oxalate/water system was determined. PMID:27482644

  5. 46 CFR 148.205 - Ammonium nitrate and ammonium nitrate fertilizers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Ammonium nitrate and ammonium nitrate fertilizers. 148... Materials § 148.205 Ammonium nitrate and ammonium nitrate fertilizers. (a) This section applies to the stowage and transportation in bulk of ammonium nitrate and the following fertilizers composed of...

  6. 46 CFR 148.205 - Ammonium nitrate and ammonium nitrate fertilizers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Ammonium nitrate and ammonium nitrate fertilizers. 148... Materials § 148.205 Ammonium nitrate and ammonium nitrate fertilizers. (a) This section applies to the stowage and transportation in bulk of ammonium nitrate and the following fertilizers composed of...

  7. 46 CFR 148.205 - Ammonium nitrate and ammonium nitrate fertilizers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Ammonium nitrate and ammonium nitrate fertilizers. 148... Materials § 148.205 Ammonium nitrate and ammonium nitrate fertilizers. (a) This section applies to the stowage and transportation in bulk of ammonium nitrate and the following fertilizers composed of...

  8. 46 CFR 148.205 - Ammonium nitrate and ammonium nitrate fertilizers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Ammonium nitrate and ammonium nitrate fertilizers. 148... Materials § 148.205 Ammonium nitrate and ammonium nitrate fertilizers. (a) This section applies to the stowage and transportation in bulk of ammonium nitrate and the following fertilizers composed of...

  9. Comparative DFT study of crystalline ammonium perchlorate and ammonium dinitramide.

    PubMed

    Zhu, Weihua; Wei, Tao; Zhu, Wei; Xiao, Heming

    2008-05-22

    The electronic structure, vibrational properties, absorption spectra, and thermodynamic properties of crystalline ammonium perchlorate (AP) and ammonium dinitramide (ADN) have been comparatively studied using density functional theory in the local density approximation. The results shows that the p states for the two solids play a very important role in their chemical reaction. From the low frequency to high frequency region, ADN has more motion modes for the vibrational frequencies than AP. The absorption spectra of AP and ADN display a few, strong bands in the fundamental absorption region. The thermodynamic properties show that ADN is easier to decompose than AP as the temperature increases. PMID:18396853

  10. Anaerobic ammonium oxidation for treatment of ammonium-rich wastewaters*

    PubMed Central

    Zhang, Lei; Zheng, Ping; Tang, Chong-jian; Jin, Ren-cun

    2008-01-01

    The concept of anaerobic ammonium oxidation (ANAMMOX) is presently of great interest. The functional bacteria belonging to the Planctomycete phylum and their metabolism are investigated by microbiologists. Meanwhile, the ANAMMOX is equally valuable in treatment of ammonium-rich wastewaters. Related processes including partial nitritation-ANAMMOX and completely autotrophic nitrogen removal over nitrite (CANON) have been developed, and lab-scale experiments proved that both processes were quite feasible in engineering with appropriate control. Successful full-scale practice in the Netherlands will accelerate application of the process in future. This review introduces the microbiology and more focuses on application of the ANAMMOX process. PMID:18500782

  11. TREATMENT OF AMMONIUM NITRATE SOLUTIONS

    DOEpatents

    Boyer, T.W.; MacHutchin, J.G.; Yaffe, L.

    1958-06-10

    The treatment of waste solutions obtained in the processing of neutron- irradiated uranium containing fission products and ammonium nitrate is described. The object of this process is to provide a method whereby the ammonium nitrate is destroyed and removed from the solution so as to permit subsequent concentration of the solution.. In accordance with the process the residual nitrate solutions are treated with an excess of alkyl acid anhydride, such as acetic anhydride. Preferably, the residual nitrate solution is added to an excess of the acetic anhydride at such a rate that external heat is not required. The result of this operation is that the ammonium nitrate and acetic anhydride react to form N/sub 2/ O and acetic acid.

  12. Collagen type VI myopathies.

    PubMed

    Bushby, Kate M D; Collins, James; Hicks, Debbie

    2014-01-01

    Mutations in each of the three collagen VI genes COL6A1, COL6A2 and COL6A3 cause two main types of muscle disorders: Ullrich congenital muscular dystrophy, a severe phenotype, and a mild to moderate phenotype Bethlem myopathy. Recently, two additional phenotypes, including a limb-girdle muscular dystrophy phenotype and an autosomal recessive myosclerosis reported in one family with mutations in COL6A2 have been reported. Collagen VI is an important component of the extracellular matrix which forms a microfibrillar network that is found in close association with the cell and surrounding basement membrane. Collagen VI is also found in the interstitial space of many tissues including muscle, tendon, skin, cartilage, and intervertebral discs. Thus, collagen VI mutations result in disorders with combined muscle and connective tissue involvement, including weakness, joint laxity and contractures, and abnormal skin findings.In this review we highlight the four recognized clinical phenotypes of collagen VI related - myopathies; Ullrich congenital muscular dystrophy (UCMD), Bethlem myopathy (BM), autosomal dominant limb-girdle muscular dystrophy phenotype and autosomal recessive myosclerosis. We discuss the diagnostic criteria of these disorders, the molecular pathogenesis, genetics, treatment, and related disorders. PMID:24443028

  13. The chronic toxicity of molybdate to marine organisms. I. Generating reliable effects data.

    PubMed

    Heijerick, D G; Regoli, L; Stubblefield, W

    2012-07-15

    A scientific research program was initiated by the International Molybdenum Association (IMOA) which addressed identified gaps in the environmental toxicity data for the molybdate ion (MoO(4)(2-)). These gaps were previously identified during the preparation of EU-REACH-dossiers for different molybdenum compounds (European Union regulation on Registration, Evaluation, Authorization and Restriction of Chemical substances; EC, 2006). Evaluation of the open literature identified few reliable marine ecotoxicological data that could be used for deriving a Predicted No-Effect Concentration (PNEC) for the marine environment. Rather than calculating a PNEC(marine) using the assessment factor methodology on a combined freshwater/marine dataset, IMOA decided to generate sufficient reliable marine chronic data to permit derivation of a PNEC by means of the more scientifically robust species sensitivity distribution (SSD) approach (also called the statistical extrapolation approach). Nine test species were chronically exposed to molybdate (added as sodium molybdate dihydrate, Na(2)MoO(4)·2H(2)O) according to published standard testing guidelines that are acceptable for a broad range of regulatory purposes. The selected test organisms were representative for typical marine trophic levels: micro-algae/diatom (Phaeodactylum tricornutum, Dunaliella tertiolecta), macro-alga (Ceramium tenuicorne), mysids (Americamysis bahia), copepod (Acartia tonsa), fish (Cyprinodon variegatus), echinoderms (Dendraster exentricus, Strongylocentrotus purpuratus) and molluscs (Mytilus edulis, Crassostrea gigas). Available NOEC/EC(10) levels ranged between 4.4 mg Mo/L (blue mussel M. edulis) and 1174 mg Mo/L (oyster C. gigas). Using all available reliable marine chronic effects data that are currently available, a HC(5,50%) (median hazardous concentration affecting 5% of the species) of 5.74(mg Mo)/L was derived with the statistical extrapolation approach, a value that can be used for national and

  14. Molybdate uptake by Agrobacterium tumefaciens correlates with the cellular molybdenum cofactor status.

    PubMed

    Hoffmann, Marie-Christine; Ali, Koral; Sonnenschein, Marleen; Robrahn, Laura; Strauss, Daria; Narberhaus, Franz; Masepohl, Bernd

    2016-09-01

    Many enzymes require the molybdenum cofactor, Moco. Under Mo-limiting conditions, the high-affinity ABC transporter ModABC permits molybdate uptake and Moco biosynthesis in bacteria. Under Mo-replete conditions, Escherichia coli represses modABC transcription by the one-component regulator, ModE, consisting of a DNA-binding and a molybdate-sensing domain. Instead of a full-length ModE protein, many bacteria have a shorter ModE protein, ModE(S) , consisting of a DNA-binding domain only. Here, we asked how such proteins sense the intracellular molybdenum status. We show that the Agrobacterium tumefaciens ModE(S) protein Atu2564 is essential for modABC repression. ModE(S) binds two Mo-boxes in the modA promoter as shown by electrophoretic mobility shift assays. Northern analysis revealed cotranscription of modE(S) with the upstream gene, atu2565, which was dispensable for ModE(S) activity. To identify genes controlling ModE(S) function, we performed transposon mutagenesis. Tn5 insertions resulting in derepressed modA transcription mapped to the atu2565-modE(S) operon and several Moco biosynthesis genes. We conclude that A. tumefaciens ModE(S) activity responds to Moco availability rather than to molybdate concentration directly, as is the case for E. coli ModE. Similar results in Sinorhizobium meliloti suggest that Moco dependence is a common feature of ModE(S) regulators. PMID:27196733

  15. Engineering Test Satellite VI (ETS-VI)

    NASA Technical Reports Server (NTRS)

    Horii, M.; Funakawa, K.

    1991-01-01

    The Engineering Test Satellite-VI (ETS-VI) is being developed as the third Japanese three-axis stabilized engineering test satellite to establish the 2-ton geostationary operational satellite bus system and to demonstrate the high performance satellite communication technology for future operational satellites. The satellite is expected to be stationed at 154 deg east latitude. It will be launched from the Tanegashima Space Center in Japan by a type H-II launch vehicle. The Deep Space Network (DSN) will support the prelaunch compatibility test, data interface verification testing, and launch rehersals. The DSN primary support period is from launch through the final AEF plus 1 hour. Contingency support is from final AEF plus 1 hour until launch plus 1 month. The coverage will consist of all the 26-m antennas as prime and the 34-m antennas at Madrid and Canberra as backup. Maximum support will consist of two 8-hour tracks per station for a 7-day period, plus the contingency support, if required. Information is given in tabular form for DSN support, telemetry, command, and tracking support responsibility.

  16. [Adsorptive Stabilization of Soil Cr (VI) Using HDTMA Modified Montmorillonite].

    PubMed

    2016-03-15

    A series of organo-montomorillonites were prepared using Na-montomorillonite and hexadecyl trimethyl ammonium bromide (HDTMA). The organo-montomorillonites were then investigated for the remediation of Cr(VI) contaminated soils. FT-IR, XRD, SEM and N2 -BET, CEC, Zeta potential measurement were conducted to understand the structural changes of montmorillonites as different amounts of HDTMAs were added as modifier. The characterization results indicated that the clay interlayer spacing distance increased from 1. 25 nm to 2. 13 nm, the clay surface roughness decreased, the clay surface area reduced from 38.91 m² · g⁻¹ to 0.42 m² · g⁻¹, the clay exchangeable cation amount reduced from 62 cmol · kg⁻¹ to 9.9 cmol · kg⁻¹ and the clay surface charge changed from -29.1 mV to 5.59 mV as the dosage of HDTMA in montmorillonite was increased. The TCLP (toxicity characteristic leaching procedure) was used to evaluate the leachate toxicity of Cr(VI). The effects of the initial soil Cr(VI) concentration, montmorillonites dosage, reaction time and HDTMA modification amount were investigated, respectively. The results revealed that modification of montmorillonites would manifest an attenuated physical adsorptive effect and an enhanced electrostatic adsorptive effect on Cr(VI), suggesting electrostatic effect was the major force that resulted in improved Cr(VI) adsorption onto HDTMA modified montmorillonites. PMID:27337898

  17. Electrical and mechanical properties of ZnO doped silver-molybdate glass-nanocomposite system

    NASA Astrophysics Data System (ADS)

    Kundu, Ranadip; Roy, Debasish; Bhattacharya, Sanjib

    2016-05-01

    Zno doped silver-molybdate glass-nanocomposites, 0.3 Ag2O - 0.7 [0.075 ZnO - 0.925 MoO3] have been prepared by melt-quenching method. Ionic conductivity of these glass-nanocomposites has been measured in wide temperature and frequency windows. Vicker's hardness methods have been employed to study micro-hardness of the as-prepared samples. Heat-treated counterparts for this glass-nanocomposites system has been analyzed in different temperature to observe the changes in conductivity as well as micro-hardness for that system.

  18. Intelsat VI Capture Attempt

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The first single crewmember EVA capture attempt of the Intelsat VI as seen from Endeavour's aft flight deck windows. EVA Mission Specialist Pierre Thuot standing on the Remote Manipulator System (RMS) end effector platform, with the satellite capture bar attempting to attach it to the free floating communications satellite.

  19. ESL VI Curriculum Guide.

    ERIC Educational Resources Information Center

    Flander, Leonard

    This curriculum guide for English as a Second Language (ESL) Level VI is the sixth of six in a Guam Community College ESL project series. The other five guides, a companion teacher's guide and pre- and post-tests are available separately (see note). The entire project centers around the Peabody Kits P, Level P, Level 1, Level 2, Level 3, and the…

  20. Chromium(VI)

    Integrated Risk Information System (IRIS)

    Chromium ( VI ) ; CASRN 18540 - 29 - 9 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic

  1. 21 CFR 184.1137 - Ammonium carbonate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... sublimation of a mixture of ammonium sulfate and calcium carbonate and occurs as a white powder or a hard... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Ammonium carbonate. 184.1137 Section 184.1137 Food... GRAS § 184.1137 Ammonium carbonate. (a) Ammonium carbonate ((NH4)2CO3, CAS Reg. No. 8000-73-5) is...

  2. 21 CFR 556.375 - Maduramicin ammonium.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Tolerances for Residues of New Animal Drugs § 556.375 Maduramicin ammonium. A tolerance is established for residues of maduramicin ammonium in chickens as follows: (a) A tolerance for maduramicin ammonium...

  3. 21 CFR 582.1141 - Ammonium phosphate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Ammonium phosphate. 582.1141 Section 582.1141 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1141 Ammonium phosphate. (a) Product. Ammonium phosphate (mono- and dibasic). (b)...

  4. 21 CFR 582.1141 - Ammonium phosphate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

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

  5. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    .... No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures, and ammonium chloride is recovered... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ammonium chloride. 184.1138 Section 184.1138...

  6. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    .... No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures, and ammonium chloride is recovered... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ammonium chloride. 184.1138 Section 184.1138...

  7. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    .... No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures, and ammonium chloride is recovered... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ammonium chloride. 184.1138 Section 184.1138...

  8. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    .... No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures, and ammonium chloride is recovered... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ammonium chloride. 184.1138 Section 184.1138...

  9. 21 CFR 582.1143 - Ammonium sulfate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Ammonium sulfate. 582.1143 Section 582.1143 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1143 Ammonium sulfate. (a) Product. Ammonium sulfate. (b) Conditions of use. This...

  10. 21 CFR 582.1143 - Ammonium sulfate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Ammonium sulfate. 582.1143 Section 582.1143 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1143 Ammonium sulfate. (a) Product. Ammonium sulfate. (b) Conditions of use. This...

  11. 21 CFR 582.1143 - Ammonium sulfate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ammonium sulfate. 582.1143 Section 582.1143 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1143 Ammonium sulfate. (a) Product. Ammonium sulfate. (b) Conditions of use. This...

  12. 21 CFR 582.1143 - Ammonium sulfate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Ammonium sulfate. 582.1143 Section 582.1143 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1143 Ammonium sulfate. (a) Product. Ammonium sulfate. (b) Conditions of use. This...

  13. 21 CFR 582.1143 - Ammonium sulfate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Ammonium sulfate. 582.1143 Section 582.1143 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1143 Ammonium sulfate. (a) Product. Ammonium sulfate. (b) Conditions of use. This...

  14. 21 CFR 556.375 - Maduramicin ammonium.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Tolerances for Residues of New Animal Drugs § 556.375 Maduramicin ammonium. A tolerance is established for residues of maduramicin ammonium in chickens as follows: (a) A tolerance for maduramicin ammonium...

  15. 21 CFR 556.375 - Maduramicin ammonium.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Tolerances for Residues of New Animal Drugs § 556.375 Maduramicin ammonium. A tolerance is established for residues of maduramicin ammonium in chickens as follows: (a) A tolerance for maduramicin ammonium...

  16. 21 CFR 556.375 - Maduramicin ammonium.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... residues of maduramicin ammonium in chickens as follows: (a) A tolerance for maduramicin ammonium (marker residue) in chickens is 0.38 parts per million in fat (target tissue). A tolerance refers to the... animals. (b) The safe concentrations for total maduramicin ammonium residues in uncooked edible...

  17. 21 CFR 582.1141 - Ammonium phosphate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Ammonium phosphate. 582.1141 Section 582.1141 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1141 Ammonium phosphate. (a) Product. Ammonium phosphate (mono- and dibasic). (b)...

  18. 21 CFR 582.1141 - Ammonium phosphate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Ammonium phosphate. 582.1141 Section 582.1141 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1141 Ammonium phosphate. (a) Product. Ammonium phosphate (mono- and dibasic). (b)...

  19. 21 CFR 582.1141 - Ammonium phosphate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Ammonium phosphate. 582.1141 Section 582.1141 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1141 Ammonium phosphate. (a) Product. Ammonium phosphate (mono- and dibasic). (b)...

  20. Extraction of urea and ammonium ion

    NASA Technical Reports Server (NTRS)

    Anselmi, R. T.; Husted, R. R.; Schulz, J. R.

    1977-01-01

    Water purification system keeps urea and ammonium ion concentration below toxic limits in recirculated water of closed loop aquatic habitat. Urea is first converted to ammonium ions and carbon dioxide by enzygmatic action. Ammonium ions are removed by ion exchange. Bioburden is controlled by filtration through 0.45 micron millipore filters.

  1. Spontaneous formation of crystalline lithium molybdate from solid reagents at room temperature.

    PubMed

    Yip, Thomas W S; Cussen, Edmund J; Wilson, Claire

    2010-01-14

    Lithium molybdate has been prepared by grinding LiOH x H(2)O with MoO(3) in air at room temperature. X-Ray powder diffraction data show that the formation of highly crystalline Li(2)MoO(4) is largely complete after 10 min. The phenacite structure of this material is the same as that derived from an X-ray diffraction study of a single crystal obtained from aqueous solution [R3; a = 14.3178(14) A, c = 9.5757(9) A]. Anhydrous lithium hydroxide fails to give the same reaction indicating that the water of crystallisation of LiOH x H(2)O is a vital component in this rapid synthesis. Differential scanning calorimetry measurements show that this reaction can proceed spontaneously between the two stable solid reagents at sub-ambient temperatures and is driven by the liberation of water from the crystalline lattice. Lithium molybdate prepared in this manner has significantly smaller and more regularly shaped particles than samples prepared by other synthetic methods. PMID:20023976

  2. Polymorphism in yttrium molybdate Y{sub 2}Mo{sub 3}O{sub 12}

    SciTech Connect

    Gates, Stacy D.; Lind, Cora

    2007-12-15

    Yttrium molybdate (Y{sub 2}Mo{sub 3}O{sub 12}) has been prepared by non-hydrolytic sol-gel chemistry. The phase evolution upon heating was investigated using in situ and ex situ heat treatments combined with powder X-ray diffraction. This method has led to the isolation of two orthorhombic phases with different atomic connectivity. Yttrium adopts 6- and 7-coordinate sites in the Pbcn and Pba2 structures, respectively. Cocrystallization of both phases was observed in a narrow temperature range, suggesting that crystallization kinetics play a major role in phase formation. It was found that the Pba2 phase is the stable polymorph below 550 deg. C, and converts to Pbcn at higher temperatures. - Graphical abstract: Yttrium molybdate (Y{sub 2}Mo{sub 3}O{sub 12}) prepared by non-hydrolytic sol-gel chemistry crystallizes in a mixture of orthorhombic polymorphs with different atomic connectivities. The Pbcn and Pba2 phases coexist over a narrow temperature range. Crystallization of the Pbcn structure is kinetically favored. The Pba2 polymorph is the thermodynamically stable phase at low temperatures, and converts to Pbcn above 550 deg. C.

  3. Phase diagram of ammonium nitrate

    NASA Astrophysics Data System (ADS)

    Dunuwille, M.; Yoo, C. S.

    2014-05-01

    Ammonium Nitrate (AN) has often subjected to uses in improvised explosive devices, due to its wide availability as a fertilizer and its capability of becoming explosive with slight additions of organic and inorganic compounds. Yet, the origin of enhanced energetic properties of impure AN (or AN mixtures) is neither chemically unique nor well understood -resulting in rather catastrophic disasters in the past1 and thereby a significant burden on safety in using ammonium nitrates even today. To remedy this situation, we have carried out an extensive study to investigate the phase stability of AN at high pressure and temperature, using diamond anvil cells and micro-Raman spectroscopy. The present results confirm the recently proposed phase IV-to-IV' transition above 17 GPa2 and provide new constraints for the melting and phase diagram of AN to 40 GPa and 400 °C.

  4. Crystallization, data collection and phasing of the molybdate-binding protein of the phytopathogen Xanthomonas axonopodis pv. citri

    SciTech Connect

    Santacruz, C. P.; Balan, A.; Ferreira, L. C. S.; Barbosa, J. A. R. G.

    2006-03-01

    The molybdate-binding protein (ModA) from X. axonopodis pv. citri was crystallized with sodium molybdate in the presence of PEG or sulfate. The crystal diffracted to a maximum resolution of 1.7 Å and belongs to the orthorhombic space group C222{sub 1,} with unit-cell parameters a = 68.15, b = 172.14, c = 112.04 Å. Xanthomonas axonopodis pv. citri ModA protein is the ABC periplasmic binding component responsible for the capture of molybdate. The protein was crystallized with sodium molybdate using the hanging-drop vapour-diffusion method in the presence of PEG or sulfate. X-ray diffraction data were collected to a maximum resolution of 1.7 Å using synchrotron radiation. The crystal belongs to the orthorhombic space group C222{sub 1}, with unit-cell parameters a = 68.15, b = 172.14, c = 112.04 Å. The crystal structure was solved by molecular-replacement methods and structure refinement is in progress.

  5. Toxicity of sodium molybdate and sodium dichromate to Daphnia magna straus evaluated in acute, chronic, and acetylcholinesterase inhibition tests.

    PubMed

    Diamantino, T C; Guilhermino, L; Almeida, E; Soares, A M

    2000-03-01

    As a result of a widespread application in numerous industrial processes, chromium is a contaminant of many environmental systems. Chromium and their compounds are toxic to both invertebrates and vertebrates and, for this reason, there has been a search for suitable and less toxic alternatives. Molybdenum compounds have been studied as alternative to chromium compounds for some industrial applications. The toxicity of chromium is well known but the effects of molybdenum and molybdenum mining on natural populations and communities of freshwater invertebrates have not often been studied. However, chromium, and molybdenum (and their compounds) are included in the same list (List II) of European Union dangerous substances. In this study, the acute and chronic effects of sodium molybdate and sodium dichromate to Daphnia magna Straus were evaluated. Furthermore, in vitro and in vivo effects of these two metals on acetylcholinesterase (AChE) activity of D. magna Straus were investigated. LC(50) values determined at 48 h were 0.29 and 2847.5 mg L(-1) for chromium (as sodium dichromate) and molybdenum (as sodium molybdate), respectively. No significant in vitro effects of both metals on AChE were found. However, both toxicants inhibited AChE in vivo at concentrations under the respective 48-h LC(50) values. Both sodium dichromate and sodium molybdate inhibited the reproduction and growth of D. magna, but the concentrations inducing significant effects were different for the two chemicals. Sodium molybdate had significant lower toxicity to D. magna Straus than sodium dichromate. PMID:10702344

  6. Effect of chlorate, molybdate, and shikimic acid on Salmonella enterica serovar Typhimurium in aerobic and anaerobic cultures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chlorate is a bactericide that has potential as a pre-slaughter feed additive to improve food safety of meat products. The aims of the present study were to examine the effects of chlorate (5mM), molybdate (1 mM), and shikimate (0.34 mM) on the growth and chlorate-resistance of Salmonella enterica ...

  7. Determination of ammonium and organic bound nitrogen by inductively coupled plasma emission spectroscopy.

    PubMed

    Jaber, A M Y; Mehanna, N A; Sultan, S M

    2009-06-15

    The continuous flow sample introduction technique with a hydride generator system in conjunction with an inductively coupled plasma emission spectrometer (ICP-AES-HG), is used in this study for quantitative determination of ammonium and organic bound nitrogen in aqueous and solid samples. Ammonia vapor released from ammonium salt after treatment with concentrated NaOH is transferred by argon to plasma for detection at 174.273 nm using axial argon plasma mode. The calibration curves were linear within a range of 25-1000 mg L(-1)N as ammonium molybdate with correlation coefficients of better than 0.99 and limits of detection of about 10-25mg L(-1)N. The percent recovery of N (25-500 mg L(-1)N) in soft (distilled) water and high salt content (1.7 mol L(-1) NaCl) matrices was found to be in the range of about 97-102% with %RSD in the range of 4.6-0.62. The sensitivity, limit of detection, and blank contribution from the atmospheric nitrogen, were tremendously improved in this method compared with the available ICP-AES spray chamber counterpart. Furthermore, the ICP-AES-HG method gave results for real samples (soil, fertilizer, waste water) containing about 50-1800 mg L(-1)N in good agreement with those obtained by the standard Kjeldahl method. No statistical differences at the 95% confidence level on applying the t-test were observed between the values obtained by the two methods. Thus, the ICP-AES-HG method is reliable and faster than the conventional tedious Kjeldahl method, superior to the ICP-AES spray chamber method, and almost free from matrix interference which is usually a critical factor in atomic emission spectroscopic techniques. PMID:19362191

  8. Leveling effects of ammonium salts on thermal stabilities of polyethylene glycols.

    PubMed

    Xia, Juan; Song, Le Xin; Liu, Wei; Teng, Yue

    2013-10-28

    In this work, the thermal stabilities of a series of polyethylene glycols (PEG 4000, 6000 and 10000) were investigated after compositing with different kinds of inorganic salts, such as ammonium molybdate tetrahydrate (AMT), NH4VO3, (NH4)2SO4, NH4NO3, Na2SO4, Na2MoO4. It was first observed that all the ammonium salts exerted leveling effects for the thermal stabilities of the PEGs. In other words, the presence of the ammonium salts caused the occurrence of the maximum decomposition rates of the PEGs with the same repeat sequence but different chain lengths at almost the same temperatures. Leveling effects were defined by three parameters: leveling spans, leveling degrees and dispersion degrees of leveling. Further experiments revealed that leveling effects also occur in similar types of polymers: polypropylene glycols (PPG 2000, 3000 and 4000). A series of independent experiments including Fourier transformation infrared spectroscopy, Raman spectroscopy, differential scanning calorimetry, time-of-flight mass spectrometry, conductivity and field-emission scanning electron microscopy were performed to explore the origin of leveling effects. We consider that the interaction between inorganic ions and polymer molecules and the Hofmeister effect of ions in solution are two important factors affecting the stability of salt–polymer composites, because they can contribute to decrease the interaction between the polymer chains, leading to changes in the conformation and pyrolysis mode of polymers. We believe that the finding of leveling effects would be significant for both basic and applied research of soft matter. PMID:26029781

  9. Structure of Ice VI.

    PubMed

    Kamb, B

    1965-10-01

    Ice VI, a high-pressure form of density 1.31 g cm-(3), has a tetragonal cell of dimensions a = 6.27 A, c = 5.79 A, space group P4(2)/nmc, each cell containing ten water molecules. The structure is built up of hydrogen-bonded chdins of water molecules that are analogs of the tectosilicate chains out of which the fibrous zeolites are constructed. The chains in ice VI are linked laterally to one another to form an open, zeolite-like framework. The cavities in this framework are filled with a second framework identical with the first. The two frameworks interpenetrate but do not interconnect, and the complete structure can thus be considered a "self-clathrate." This structural feature is a natural way to achieve high density in tetrahedrally linked framework structures. PMID:17787274

  10. Intelsat VI antenna system

    NASA Astrophysics Data System (ADS)

    Caulfield, M. F.; Lane, S. O.; Taormina, F. A.

    The antenna system design of a series of five new communications satellites known as Intelsat VI is described in detail. Each satellite will utilize 50 transponders operating in the C and K band portions of the frequency spectrum. The transponders are interconnectible using either static switch matrices or a network which provides satellite switched time division multiple access capability. The antenna coverages, characteristics, and special design features are shown and discussed.

  11. Sasse Modeling of First Cycle Neptunium (VI) Recovery Flowsheet

    SciTech Connect

    Laurinat, J. E.

    2006-04-01

    A flowsheet has been proposed to separate neptunium from solutions in H-Canyon Tanks 16.4, 12.5, and 11.7 in the First Cycle solvent extraction banks, in which cerium(IV) (Ce(IV)) serves as an agent to oxidize neptunium to neptunium(VI) (Np(VI)). A SASSE (Spreadsheet Algorithm for Stagewise Solvent Extraction) spreadsheet model indicates that the proposed flowsheet is a feasible method for separating neptunium and uranium from sulfates, thorium, and other metal impurities. The proposed flowsheet calls for stripping the sulfates, thorium, and other metal impurities into the 1AW stream and extracting and then stripping the neptunium and uranium into the 1BP stream. SASSE predicts that separation of thorium from the other actinides can be accomplished with actinide losses of 0.01% or less. It is assumed that other metal impurities such as iron, aluminum, and fission products will follow the thorium into 1AW. Due to an organic/aqueous distribution coefficient that is close to one, SASSE predicts that plutonium(VI) (Pu(VI)) is split between the A Bank and B Bank aqueous output streams, with 27% going to 1AW and 73% going to 1BP. An extrapolated distribution coefficient based on unvalidated Ce(IV) distribution measurements at a single nitrate concentration and a comparison with thorium(IV) (Th(IV)) distributions indicates that Ce(IV) could reflux in 1B Bank. If the Ce(IV) distribution coefficient is lower than would be predicted by this single point extrapolation, but still higher than the distribution coefficient for Th(IV), then Ce(IV) would follow Np(VI) and uranium(VI) (U(VI)) into 1BP. The SASSE model was validated using data from a 1964 oxidizing flowsheet for the recovery of Np(VI) in Second Cycle. For the proposed flowsheet to be effective in recovering neptunium, the addition of approximately 0.025 M ceric ammonium nitrate (Ce(NH4)2(NO3)6) to both the 1AF and 1AS streams is required to stabilize the neptunium in the +6

  12. Lasing properties of new Nd 3+-doped tungstate, molybdate, and fluoride materials under selective optical pumping

    NASA Astrophysics Data System (ADS)

    Šulc, Jan; Jelínkova, Helena; Basiev, Tolstoban T.; Doroschenko, Maxim E.; Ivleva, Ludmila I.; Osiko, Vyacheslav V.; Zverev, Peter G.

    2006-02-01

    The purpose of this work was to determine the relative efficiencies of new Nd 3+-doped laser active/Raman - tungstate, molybdate, and fluoride - materials (SrWO 4, PbWO 4, BaWO 4, SrMoO 4, PbMoO 4, SrF II, and LaF 3) under selective longitudinal optical pumping by the alexandrite (~750nm), or diode (~800nm) laser. Crystals with various length, orientations and active ions concentrations were tested. To optimize the output of the tested lasers a set of input dichroic and output dielectric mirrors with different reflectivities were used. For realized lasers operating at pulsed free-running regime, threshold energy, slope efficiency, emission wavelength, and radiation polarization were determined. For each crystal, fluorescence lifetime and absorption coefficient under given pumping were established. The slope efficiency in case of Nd 3+:PbMoO 4 laser at wavelength 1054nm was measured to be 54.3% with total efficiency of 46% which is the best result obtained for all new tested crystals. For Nd 3+ doped SrWO 4, PbWO 4, and BaWO 4 crystals simultaneous laser and self-Raman emission were demonstrated in Q-switched regime. Thus newly proposed laser Raman crystals demonstrate high efficiency for Nd 3+ laser oscillations comparable with well known and widely used Nd:KGW crystal. Further improvement in the quality of tungstate and molybdate type crystals should result in further increase in lasing efficiency at 1.06μm wavelength. Self Raman frequency conversion of Nd 3+-laser oscillations in these crystals should result in high efficient pulse shortening, high peak power and new wavelengths in 1.2-1.5μm wavelength region.

  13. Molybdate:sulfate ratio affects redox metabolism and viability of the dinoflagellate Lingulodinium polyedrum.

    PubMed

    Barros, M P; Hollnagel, H C; Glavina, A B; Soares, C O; Ganini, D; Dagenais-Bellefeuille, S; Morse, D; Colepicolo, P

    2013-10-15

    Molybdenum is a transition metal used primarily (90% or more) as an additive to steel and corrosion-resistant alloys in metallurgical industries and its release into the environment is a growing problem. As a catalytic center of some redox enzymes, molybdenum is an essential element for inorganic nitrogen assimilation/fixation, phytohormone synthesis, and free radical metabolism in photosynthesizing species. In oceanic and estuarine waters, microalgae absorb molybdenum as the water-soluble molybdate anion (MoO4(2-)), although MoO4(2-) uptake is thought to compete with uptake of the much more abundant sulfate anion (SO4(2-), approximately 25 mM in seawater). Thus, those aspects of microalgal biology impacted by molybdenum would be better explained by considering both MoO4(2-) and SO4(2-) concentrations in the aquatic milieu. This work examines toxicological, physiological and redox imbalances in the dinoflagellate Lingulodinium polyedrum that have been induced by changes in the molybdate:sulfate ratios. We prepared cultures of Lingulodinium polyedrum grown in artificial seawater containing eight different MoO4(2-) concentrations (from 0 to 200 μM) and three different SO4(2-) concentrations (3.5 mM, 9.6 mM and 25 mM). We measured sulfur content in cells, the activities of the three major antioxidant enzymes (superoxide dismutase, catalase, and ascorbate peroxidase), indexes of oxidative modifications in proteins (carbonyl content) and lipids (thiobarbituric acid-reactive substances, TBARS), the activities of the molybdenum-dependent enzymes xanthine oxidase and nitrate reductase, expression of key protein components of dinoflagellate photosynthesis (peridinin-chlorophyll a protein and ribulose-1,5-biphosphate carboxylase/oxidase) and growth curves. We find evidence for Mo toxicity at relatively high [MoO4(2-)]:[SO4(2-)] ratios. We also find evidence for extensive redox adaptations at Mo levels well below lethal levels. PMID:24036534

  14. Molybdate reduction by Escherichia coli K-12 and its chl mutants

    SciTech Connect

    Campbell, A.M.; del Camipillo-Campbell, A.; Villaret, D.B.

    1985-01-01

    During anaerobic growth, Escherichia coli can reduce phosphomolybdate. The reduction can also be carried out by washed cells suspended in buffer at pH 5.7. Phosphate, molybdate, glucose, cells, and anaerobic conditions are required. Reduction is inhibited by 200 ..mu..M chromate, 290 ..mu..M nitrite, 10 mM tungstate, or 20 mM cysteine. Wild-type (chl/sup +/) cells are inhibited by addition of 200 ..mu..M nitrate, but chlA, chlB, and chlE mutants are not. The inhibition of chl/sup +/ cells results from reduction of nitrate to nitrite. This nitrate reduction is not catalyzed by nitrate reductase. Wild-type cells are more sensitive than chl mutants to inhibition by nitrite and cysteine but more resistant to chromate. Pregrowth of chlD cells in 1 mM Na/sub 2/-MoO/sub 4/ increases their sensitivity to nitrite and cysteine, and pregrowth of chl/sup +/ cells in 1 mM Na-MoO/sub 4/ increases their resistance to these agents. Assays of biotin sulfoxide reductase show that the tightness of the chlD block depends on growth conditions; chlD cells grown aerobically in tryptone broth make about 50% as much active enzyme as chl/sup +/ cells, whereas chlD cells grown anaerobically with tryptone plus glucose make less than 10%. The effect of anaerobic pregrowth on the inhibition of molybdate reduction by added nitrate indicates that in vivo nitrate reduction responds to growth conditions in the same manner as biotin sulfoxide reductase does.

  15. Molybdate Reduction by Escherichia coli K-12 and Its chl Mutants

    NASA Astrophysics Data System (ADS)

    Campbell, Allan M.; del Campillo-Campbell, Alice; Villaret, Douglas B.

    1985-01-01

    During anaerobic growth, Escherichia coli can reduce phosphomolybdate. The reduction can also be carried out by washed cells suspended in buffer at pH 5.7. Phosphate, molybdate, glucose, cells, and anaerobic conditions are required. Reduction is inhibited by 200 μ M chromate, 290 μ M nitrite, 10 mM tungstate, or 20 mM cysteine. Wild-type (chl+) cells are inhibited by addition of 200 μ M nitrate, but chlA, chlB, and chlE mutants are not. The inhibition of chl+ cells results from reduction of nitrate to nitrite. This nitrate reduction is not catalyzed by nitrate reductase. Wild-type cells are more sensitive than chl mutants to inhibition by nitrite and cysteine but more resistant to chromate. Pregrowth of chlD cells in 1 mM Na2MoO4 increases their sensitivity to nitrite and cysteine, and pregrowth of chl+ cells in 1 mM Na2MoO4 increases their resistance to these agents. Assays of biotin sulfoxide reductase show that the tightness of the chlD block depends on growth conditions; chlD cells grown aerobically in tryptone broth make about 50% as much active enzyme as chl+ cells, whereas chlD cells grown anaerobically with tryptone plus glucose make less than 10%. The effect of anaerobic pregrowth on the inhibition of molybdate reduction by added nitrate indicates that in vivo nitrate reduction responds to growth conditions in the same manner as biotin sulfoxide reductase does.

  16. Characterization of Molybdate Conversion Coatings for Aluminum Alloys by Electrochemical Impedance Spectroscopy

    NASA Technical Reports Server (NTRS)

    Calle, Luz Marina

    2000-01-01

    Electrochemical impedance spectroscopy (EIS) was used to investigate the corrosion inhibiting properties of newly developed proprietary molybdate conversion coatings on aluminum alloy 2024-T3 under immersion in aerated 5% (w/w) NaCl. Corrosion potential and EIS measurements were gathered for six formulations of the coating at several immersion times for two weeks. Nyquist as well as Bode plots of the data were obtained. The conversion-coated alloy panels showed an increase in the corrosion potential during the first 24 hours of immersion that later subsided and approached a steady value. Corrosion potential measurements indicated that formulations A, D, and F exhibit a protective effect on aluminum 2024-T3. The EIS spectra of the conversion-coated alloy were characterized by an impedance that is higher than the impedance of the bare alloy at all the immersion times. The low frequency impedance, Z(sub lf) (determined from the value at 0.05 Hz) for the conversion-coated alloy was higher at all the immersion times than that of the bare panel. This indicates improvement of corrosion resistance with addition of the molybdate conversion coating. Scanning electron microscopy (SEM) revealed the presence of cracks in the coating and the presence of cubic crystals believed to be calcium carbonate. Energy dispersive spectroscopy (EDS) of the test panels revealed the presence of high levels of aluminum, oxygen, and calcium but did not detect the presence of molybdenum on the test panels. X-ray photoelectron spectroscopy (XPS) indicated the presence of less than 0.01 atomic percent molybdenum on the surface of the coating.

  17. Controllable synthesis and characterization of cadmium molybdate octahedral nanocrystals by coprecipitation method

    SciTech Connect

    Shahri, Zahra; Sobhani, Azam; Salavati-Niasari, Masoud

    2013-10-15

    Graphical abstract: CdMoO{sub 4} nanocrystals have been synthesized via coprecipitation method by using Cd(Sal){sub 2} and (NH{sub 4}){sub 6}Mo{sub 7}O{sub 24}·4H{sub 2}O as starting materials in water. Effects of temperature, reaction time, solvent, surfactant, cadmium and molybdate sources were investigated to reach optimum condition. It was found that particle size, morphology and phase of the final products could be greatly influenced via these parameters. - Highlights: • A facile coprecipitation method was successfully employed to prepare CdMoO{sub 4}. • The effects of some parameters were investigated. • PEG600, PVP, SDS and CTAB were used as surfactant. • Optimum condition for preparation CdMoO{sub 4} nanocrystals was investigated. - Abstract: Cadmium molybdate (CdMoO{sub 4}) nanocrystals have been successfully synthesized via coprecipitation method by using Cd(Sal){sub 2} (Sal = salicylidene) and (NH{sub 4}){sub 6}Mo{sub 7}O{sub 24}·4H{sub 2}O as starting materials in water as solvent. Effects of temperature, reaction time, solvent, surfactant and cadmium source were investigated to reach optimum condition. It was found that particle size, morphology and phase of the final products could be greatly influenced via these parameters. The products were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectra, photoluminescence (PL) spectroscopy, energy dispersive X-ray microanalysis (EDX), scanning electron microscopy (SEM) and transmission electron microscopy (TEM)

  18. Ammonium assmilation in spruce ectomycorrhizas

    SciTech Connect

    Chalot, M.; Brun, A.; Botton, B. ); Stewart, G. )

    1990-05-01

    Assimilation of labelled NH{sub 4}{sup +} into amino acids has been followed in ectomycorrhizal roots of spruce. Over an 18 h period of NH{sub 4}{sup +} feeding, Gln, Glu and Ala became the most abundant amino acids. Gln was also the most highly labelled amino acid during the experiment, followed by Glu and Ala. This result indicates that Gln synthesis is an important ammonium utilization reaction in spruce mycorrhizas. Addition of MSX to NH{sub 4}{sup +} fed mycorrhizas caused an inhibition of Gln accumulation with a corresponding increase in Glu, Ala and Asn levels. The supply of MSX induced a sharp diminution of {sup 15}N enrichment in both amino and amido groups of glutamine. In contrast, the {sup 15}N incorporation into Glu and derivatives (Ala and Asp) remained very high. This study demonstrates that the fungal glutamate dehydrogenase is quite operative in spruce ectomycorrhizas since it is able to sustain ammonium assimilation when glutamine synthetase is inhibited.

  19. Structural study of ammonium metatungstate

    SciTech Connect

    Christian, Joel B. Whittingham, M. Stanley

    2008-08-15

    Several techniques have been used to study the structure of the Keggin-type polyoxometalate salt ammonium metatungstate (AMT)-(NH{sub 4}){sub 6}[H{sub 2}W{sub 12}O{sub 40}]*nH{sub 2}O, a potential fuel cell catalyst. The dehydrated salt is comprised of a mixture of crystallites of different unit cells in a centered eutactic cubic configuration, with an average unit cell of a{approx_equal}12.295. Varied orientations of the Keggin ions in the cubic arrangement create the differences, and orientational variation within each unit cell size represents an energy well. Progressive hydration of each crystallite leads to expansion of the lattice, with the degree of expansion depending on the locations of the water added in relation to the Keggin ion, which is influenced by cation location and hydrogen bonding. The structural hypothesis is supported by electron diffraction of single and multicrystal samples, by powder density measurements, X-ray powder diffraction studies, synchrotron powder X-ray diffraction, and a priori structural modeling studies. Based on the structure, projected active site densities are compared with nanostructured platinum catalysts for fuel cell application. - Graphical abstract: The structure of ammonium metatungstate powders are highly dependent on hydration and POM molecule rotation, with cation and hydrogen bonding forces directing a mixture of structures that have been studied with bulk and single-crystal methods. The illustration shows Monte Carlo simulated anion structural disorder for the fully dehydrated form of the title compound.

  20. Phase Diagram of Ammonium Nitrate

    NASA Astrophysics Data System (ADS)

    Dunuwille, Mihindra; Yoo, Choong-Shik

    2013-06-01

    Ammonium Nitrate (AN) has often been subjected to uses in improvised explosive devices, due to its wide availability as a fertilizer and its capability of becoming explosive with slight additions of organic and inorganic compounds. Yet, the origin of enhanced energetic properties of impure AN (or AN mixtures) is neither chemically unique nor well understood - resulting in rather catastrophic disasters in the past1 and thereby a significant burden on safety, in using ammonium nitrates even today. To remedy this situation, we have carried out an extensive study to investigate the phase stability of AN, in different chemical environments, at high pressure and temperature, using diamond anvil cells and micro-Raman spectroscopy. The present results confirm the recently proposed phase IV-to-IV' transition above 15 GPa2 and provide new constraints for the melting and phase diagram of AN to 40 GPa and 673 K. The present study has been supported by the U.S. DHS under Award Number 2008-ST-061-ED0001.

  1. 49 CFR 176.410 - Division 1.5 materials, ammonium nitrate and ammonium nitrate mixtures.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Division 1.5 materials, ammonium nitrate and ammonium nitrate mixtures. 176.410 Section 176.410 Transportation Other Regulations Relating to... nitrate and ammonium nitrate mixtures. (a) This section prescribes requirements to be observed...

  2. 49 CFR 176.410 - Division 1.5 materials, ammonium nitrate and ammonium nitrate mixtures.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Division 1.5 materials, ammonium nitrate and ammonium nitrate mixtures. 176.410 Section 176.410 Transportation Other Regulations Relating to... nitrate and ammonium nitrate mixtures. (a) This section prescribes requirements to be observed...

  3. 49 CFR 176.410 - Division 1.5 materials, ammonium nitrate and ammonium nitrate mixtures.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Division 1.5 materials, ammonium nitrate and ammonium nitrate mixtures. 176.410 Section 176.410 Transportation Other Regulations Relating to... nitrate and ammonium nitrate mixtures. (a) This section prescribes requirements to be observed...

  4. 49 CFR 176.410 - Division 1.5 materials, ammonium nitrate and ammonium nitrate mixtures.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Division 1.5 materials, ammonium nitrate and ammonium nitrate mixtures. 176.410 Section 176.410 Transportation Other Regulations Relating to... nitrate and ammonium nitrate mixtures. (a) This section prescribes requirements to be observed...

  5. 49 CFR 176.410 - Division 1.5 materials, ammonium nitrate and ammonium nitrate mixtures.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Division 1.5 materials, ammonium nitrate and ammonium nitrate mixtures. 176.410 Section 176.410 Transportation Other Regulations Relating to... nitrate and ammonium nitrate mixtures. (a) This section prescribes requirements to be observed...

  6. Equilibrium studies of sodium-ammonium potassium-ammonium, and calcium-ammonium exchanges on clinoptilolite zeolite

    SciTech Connect

    Jama, M.A.; Yuecel, H. )

    1989-12-01

    Forward and reverse ion-exchange isotherms for the binary sodium-ammonium, potassium-ammonium, and calcium-ammonium systems on clinoptilolite have been measured in aqueous solutions at a total concentration of 0.1 equiv/dm{sup 3} and at 298 K. Prior to exchange experiments it was attempted to prepare homoionic forms of the zeolite by exhaustive treatments with appropriate salt solutions of cations. With no binary exchanges, full replacement of the cation by the ammonium ion is observed, which conflicts with some earlier work on clinoptilolite. Despite the observed partial exchange levels, clinoptilolite shows a very high preference for ammonium ion over sodium and calcium but not over potassium. Thermodynamic values for the exchanges were calculated and compared with data in the literature. Both the selectivity and thermodynamic affinity sequence, in agreement with previous work reported in the literature, are K{sup +} > NH{sub 4}{sup +} > Na{sup +} > Ca{sup 2+}.

  7. Non-destructive analysis of didymium and praseodymium molybdate crystals using energy dispersive X-ray fluorescence technique

    NASA Astrophysics Data System (ADS)

    Bhat, C. K.; Joseph, Daisy; Pandita, Sanjay; Kotru, P. N.

    2016-08-01

    Analysis of didymium (Di) and praseodymium molybdate crystals were carried out using energy dispersive X-ray fluorescence (EDXRF). The assigned empirical chemical formulae of the composites were tested and verified by the EDXRF technique by estimating experimental major elemental concentration ratios. On the Basis of these ratios, the established formulae for some of the composite materials have been verified and suggestions made for their refinement. Non-destructive technique used in this analysis enables to retain the original crystal samples and makes rapid simultaneous scan of major elements such as La, Pr, Ned and Mo as well as impurities such as Ce. Absence of samarium(Sm) in the spectrum during analysis of didymium molybdate crystals indicated an incomplete growth of mixed rare earth single crystal. These crystals (e.g.,Di) are shown to be of modified stoichiometry with Ce as trace impurity.

  8. Biodegradation of rocket propellant waste, ammonium perchlorate

    NASA Technical Reports Server (NTRS)

    Naqvi, S. M. Z.; Latif, A.

    1975-01-01

    The short term effects of ammonium perchlorate on selected organisms were studied. A long term experiment was also designed to assess the changes incurred by ammonium perchlorate on the nitrogen and chloride contents of soil within a period of 3 years. In addition, an attempt was made to produce methane gas from anaerobic fermentation of the aquatic weed, Alternanthera philoxeroides.

  9. 76 FR 62311 - Ammonium Nitrate Security Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-07

    ... FR 64280 (advance notice of proposed rulemaking); 76 FR 46908 (notice of proposed rulemaking... Program Web site in mid-October at http://www.dhs.gov/ files/ ] programs/ammonium-nitrate-security-program...; ] DEPARTMENT OF HOMELAND SECURITY Office of the Secretary 6 CFR Part 31 RIN 1601-AA52 Ammonium Nitrate...

  10. 76 FR 46907 - Ammonium Nitrate Security Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-03

    ...This proposed rule would implement anti-terrorism measures to better secure the homeland. The Department of Homeland Security would regulate the sale and transfer of ammonium nitrate pursuant to section 563 of the Fiscal Year 2008 Department of Homeland Security Appropriations Act with the purpose of preventing the use of ammonium nitrate in an act of terrorism. This proposed rule seeks......

  11. Ammonium nonanoate broadcast application over onions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ammonium nonanoate occurs in nature and is primarily formed from biodegradation of higher fatty acids. Racer (40% ammonium nonaoate) is a potential contact herbicide for weed control in organic crop production. Field research was conducted in southeast Oklahoma (Atoka County, Lane, OK) to determin...

  12. Effect of Vanadate, Molybdate, and Azide on Membrane-Associated ATPase and Soluble Phosphatase Activities of Corn Roots 1

    PubMed Central

    Gallagher, Sean R.; Leonard, Robert T.

    1982-01-01

    The effects of vanadate, molybdate, and azide on ATP phosphohydrolase (ATPase) and acid phosphatase activities of plasma membrane, mitochondrial, and soluble supernatant fractions from corn (Zea mays L. WF9 × MO17) roots were investigated. Azide (0.1-10 millimolar) was a selective inhibitor of pH 9.0-ATPase activity of the mitochondrial fraction, while molybdate (0.01-1.0 millimolar) was a relatively selective inhibitor of acid phosphatase activity in the supernatant fraction. The pH 6.4-ATPase activity of the plasma membrane fraction was inhibited by vanadate (10-500 micromolar), but vanadate, at similar concentrations, also inhibited acid phosphatase activity. This result was confirmed for oat (Avena sativa L.) root and coleoptile tissues. While vanadate does not appear to be a selective inhibitor, it can be used in combination with molybdate and azide to distinguish the plasma membrane ATPase from mitochondrial ATPase or supernatant acid phosphatase. Vanadate appeared to be a noncompetitive inhibitor of the plasma membrane ATPase, and its effectiveness was increased by K+. K+-stimulated ATPase activity was inhibited by 50% at about 21 micromolar vanadate. The rate of K+ transport in excised corn root segments was inhibited by 66% by 500 micromolar vanadate. PMID:16662676

  13. Surface properties of AZ91 magnesium alloy after PEO treatment using molybdate salts and low current densities

    NASA Astrophysics Data System (ADS)

    Pezzato, Luca; Brunelli, Katya; Napolitani, Enrico; Magrini, Maurizio; Dabalà, Manuele

    2015-12-01

    Plasma electrolytic oxidation (PEO) process is a recently developed electrochemical method used to produce on the surface of various metals oxide ceramic coatings that improve corrosion and wear properties of the substrate. In this work, PEO process was applied on AZ91 magnesium alloy using low current densities (0.05 A/cm2) and an alkaline solution of silicates with different concentrations of sodium molybdate (0.3-3 g/l). The effect of the low current densities of process and of molybdate salts on the corrosion resistance of the coatings was studied with potentiodynamic polarization tests and electrochemical impedance spectroscopy (EIS) in chloride and sulfate environment. The morphology, the phases and the chemical composition of the coatings were examined using a scanning electron microscope equipped with EDS, X-ray diffraction, secondary ion mass spectrometry and X-ray photoelectron spectroscopy. The corrosion properties of the PEO coated samples were remarkably improved if compared with the uncoated samples. The addition of sodium molybdate, in determinate conditions, had a positive effect on the characteristics of the coatings in terms of corrosion resistance.

  14. Evolution of Electrogenic Ammonium Transporters (AMTs)

    PubMed Central

    McDonald, Tami R.; Ward, John M.

    2016-01-01

    The ammonium transporter gene family consists of three main clades, AMT, MEP, and Rh. The evolutionary history of the AMT/MEP/Rh gene family is characterized by multiple horizontal gene transfer events, gene family expansion and contraction, and gene loss; thus the gene tree for this family of transporters is unlike the organismal tree. The genomes of angiosperms contain genes for both electrogenic and electroneutral ammonium transporters, but it is not clear how far back in the land plant lineage electrogenic ammonium transporters occur. Here, we place Marchantia polymorpha ammonium transporters in the AMT/MEP/Rh phylogeny and we show that AMTs from the liverwort M. polymorpha are electrogenic. This information suggests that electrogenic ammonium transport evolved at least as early as the divergence of bryophytes in the land plant lineage. PMID:27066024

  15. Evolution of Electrogenic Ammonium Transporters (AMTs).

    PubMed

    McDonald, Tami R; Ward, John M

    2016-01-01

    The ammonium transporter gene family consists of three main clades, AMT, MEP, and Rh. The evolutionary history of the AMT/MEP/Rh gene family is characterized by multiple horizontal gene transfer events, gene family expansion and contraction, and gene loss; thus the gene tree for this family of transporters is unlike the organismal tree. The genomes of angiosperms contain genes for both electrogenic and electroneutral ammonium transporters, but it is not clear how far back in the land plant lineage electrogenic ammonium transporters occur. Here, we place Marchantia polymorpha ammonium transporters in the AMT/MEP/Rh phylogeny and we show that AMTs from the liverwort M. polymorpha are electrogenic. This information suggests that electrogenic ammonium transport evolved at least as early as the divergence of bryophytes in the land plant lineage. PMID:27066024

  16. 49 CFR 176.415 - Permit requirements for Division 1.5, ammonium nitrates, and certain ammonium nitrate fertilizers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... nitrates, and certain ammonium nitrate fertilizers. 176.415 Section 176.415 Transportation Other... requirements for Division 1.5, ammonium nitrates, and certain ammonium nitrate fertilizers. (a) Except as... Captain of the Port (COTP). (1) Ammonium nitrate UN1942, ammonium nitrate fertilizers containing more...

  17. 49 CFR 176.415 - Permit requirements for Division 1.5, ammonium nitrates, and certain ammonium nitrate fertilizers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... nitrates, and certain ammonium nitrate fertilizers. 176.415 Section 176.415 Transportation Other... requirements for Division 1.5, ammonium nitrates, and certain ammonium nitrate fertilizers. (a) Except as... Captain of the Port (COTP). (1) Ammonium nitrate UN1942, ammonium nitrate fertilizers containing more...

  18. 49 CFR 176.415 - Permit requirements for Division 1.5, ammonium nitrates, and certain ammonium nitrate fertilizers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... nitrates, and certain ammonium nitrate fertilizers. 176.415 Section 176.415 Transportation Other... requirements for Division 1.5, ammonium nitrates, and certain ammonium nitrate fertilizers. (a) Except as... Captain of the Port (COTP). (1) Ammonium nitrate UN1942, ammonium nitrate fertilizers containing more...

  19. 49 CFR 176.415 - Permit requirements for Division 1.5, ammonium nitrates, and certain ammonium nitrate fertilizers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... nitrates, and certain ammonium nitrate fertilizers. 176.415 Section 176.415 Transportation Other... requirements for Division 1.5, ammonium nitrates, and certain ammonium nitrate fertilizers. (a) Except as... Captain of the Port (COTP). (1) Ammonium nitrate UN1942, ammonium nitrate fertilizers containing more...

  20. 49 CFR 176.415 - Permit requirements for Division 1.5, ammonium nitrates, and certain ammonium nitrate fertilizers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... nitrates, and certain ammonium nitrate fertilizers. 176.415 Section 176.415 Transportation Other... requirements for Division 1.5, ammonium nitrates, and certain ammonium nitrate fertilizers. (a) Except as... Captain of the Port (COTP). (1) Ammonium nitrate UN1942, ammonium nitrate fertilizers containing more...

  1. The nucleation kinetics of ammonium metavanadate precipitated by ammonium chloride

    NASA Astrophysics Data System (ADS)

    Du, Guangchao; Sun, Zhaohui; Xian, Yong; Jing, Han; Chen, Haijun; Yin, Danfeng

    2016-05-01

    The nucleation kinetics of ammonium metavanadate (NH4VO3) was investigated under conditions of the simulated process for precipitation of NH4VO3 from the vanadium-containing solution. Induction periods for the nucleation of NH4VO3 were experimentally determined as a function of supersaturation at temperatures from 30 to 45 °C. Using the classical nucleation theory, the interfacial tension between NH4VO3 and supersaturated solution, the nucleation rate and critical radius of nucleus for the homogeneous nucleation of NH4VO3 were estimated. With temperature increasing, the calculated interfacial tension gradually decreased from 29.78 mJ/m2 at 30 °C to 23.66 mJ/m2 at 45 °C. The nucleation rate was found to proportionally increase but the critical radius of nucleus exponentially decreased, with increase in supersaturation ratio at a constant temperature. The activation energy for NH4VO3 nucleation was obtained from the relationship between temperature and induction period, ranging from 79.17 kJ/mol at S=25 to 115.50 kJ/mol at S=15. FT-IR and Raman spectrum indicated that the crystals obtained in the precipitation process were NH4VO3.

  2. Use of molybdate as novel complex-forming selector in the analysis of polyhydric phenols by capillary zone electrophoresis.

    PubMed

    Polásek, Miroslav; Petriska, Ivan; Pospísilová, Marie; Jahodár, Ludek

    2006-03-15

    Molybdate was examined as a complex-forming additive to the CE background electrolytes (BGE) to affect the selectivity of separation of polyhydric phenols such as flavonoids (apigenin, hyperoside, luteolin, quercetin and rutin) and hydroxyphenylcarboxylic acids (ferulic, caffeic, p-coumaric and chlorogenic acid). Effects of the buffer concentrations and pH and the influence of molybdate concentration on the migration times of the analytes were investigated. In contrast to borate (which is a buffering and complex-forming agent generally used in CE at pH > or =9) molybdate forms more stable complexes with aromatic o-dihydroxy compounds and hence the complex-formation effect is observed at considerably lower pH. Model mixtures of cinnamic acid, ferulic acid, caffeic acid and 3-hydroxycinnamic acid were separated with 25 mM morpholinoethanesulfonic acid of pH 5.4 (adjusted with Tris) containing 0.15 mM sodium molybdate as the BGE (25 kV, silica capillary effective length 45 cm x 0.1mm I.D., UV-vis detection at 280 nm). With 25 mM 2-hydroxy-3-[4-(2-hydroxyethyl)-1-piperazinyl]propanesulphonic acid/Tris of pH* 7.4 containing 2mM sodium molybdate in aqueous 25% (v/v) methanol as the BGE mixtures of all the above mentioned flavonoids, p-coumaric acid and chlorogenic acid could be separated (the same capillary as above, UV-vis detection at 263 nm). The calibration curves (analyte peak area versus concentration) were rectilinear (r>0.998) for approximately 8-35 microg/ml of an analyte (with 1-nitroso-2-naphthol as internal standard). The limit of quantification values ranged between 1.1 mg l(-1) for p-coumaric acid and 2.8 mg l(-1) for quercetin. The CE method was employed for the assay of flavonoids in medicinal plant extracts. The R.S.D. values ranged between 0.9 and 4.7% (n=3) when determining luteolin (0.08%) and apigenin (0.92%) in dry Matricaria recutita flowers and rutin (1.03%) and hyperoside (0.82%) in dry Hypericum perforatum haulm. The recoveries were >96%. PMID

  3. Characterization of SiO/sub 2/-supported Mo(VI): the effect of calcination and exposure to water vapor

    SciTech Connect

    Stencel, J.M.; Diehl, J.R.; D'Este, J.R.; Makovsky, L.E.; Rodrigo, L.; Marcinkowska, K.; Adnot, A.; Roberge, P.C.; Kaliaguine, S.

    1986-09-25

    Surface structural speciation of SiO/sub 2/-supported Mo(VI) as a function of Mo impregnation technique, Mo loading, and hydration-calcination cycles is investigated by electron spectroscopy for chemical analysis (ESCA), ion scattering spectrometry (ISS), and laser Raman spectroscopy. More Mo is surface segregated by use of aqueous impregnation techniques than by use of allyl fixation. In both cases, the surface species, which are dependent upon Mo loading, include crystalline MoO/sub 3/, highly dispersed surface molybdate, and silicomolybdic acid. The symmetry within the silicomolybdic acid is destroyed by 500/sup 0/C O/sub 2/ calcination and is subsequently restored by rehydration. Consequences of the presence of such surface species with respect to the photocatalytic conversion of propane are discussed.

  4. 90-Day subchronic toxicity study of sodium molybdate dihydrate in rats.

    PubMed

    Murray, F Jay; Sullivan, Frank M; Tiwary, Asheesh K; Carey, Sandra

    2014-12-01

    This study investigated the subchronic toxicity of molybdenum (Mo) in Sprague-Dawley rats given sodium molybdate dihydrate in the diet for 90days at dose levels of 0, 5, 17 or 60mgMo/kgbw/day. The study complied with OECD Test Guideline (TG) 408, with additional examination of estrus cycles and sperm count, motility, and morphology from OECD TG 416. The overall no-observed-adverse-effect level was 17mgMo/kgbw/day, based on effects on body weight, body weight gain, food conversion efficiency and renal histopathology (females only) at 60mgMo/kgbw/day. No treatment-related adverse effects on reproductive organ weights or histopathology, estrus cycles or sperm parameters were observed at any dose level. No adverse effects were observed in the high dose animals after the 60-day recovery period, with the exception that male rats did not fully recover from reduced body weight. Serum blood, liver and kidney samples were analyzed for molybdenum, copper, zinc, manganese, iron, cobalt and selenium; high levels of molybdenum and copper were found in the serum, blood, liver and kidneys of rats treated with 60mgMo/kgbw/day. In conclusion, the LOAEL and NOAEL for molybdenum were determined to be 60 and 17mgMo/kgbw/day, respectively. PMID:24041747

  5. Kinetics and mechanism of reaction between silver molybdate and mercuric iodide in solid state

    SciTech Connect

    Beg, M.A.; Rafiuddin

    1987-05-01

    The kinetics and the mechanism of the reaction between silver molybdate and mercuric iodide were studied in the solid state by X-ray, chemical analysis, and electrical conductivity measurements. This is a multistep reaction where Ag/sub 2/HgI/sub 4/ is formed as an intermediate. In an equimolar mixture of Ag/sub 2/MoO/sub 4/ and HgI/sub 2/, AgI an HgMoO/sub 4/ are formed, whereas in a 1:2 molar mixture Ag/sub 2/HgI/sub 4/ and HgMoO/sub 4/ are formed. The data for lateral diffusion best fit the equation X/sup n/ = kt, where X is the product thickness, t is time, and k and n are constants. This is a multistep solid state ionic reaction initiated by the diffusion of HgI/sub 2/ molecules as such and not through counterdiffusion of cations.

  6. High field 207Pb spin-lattice relaxation in solid lead nitrate and lead molybdate

    NASA Astrophysics Data System (ADS)

    de Castro, Peter J.; Maher, Christopher A.; Vold, Robert L.; Hoatson, Gina L.

    2008-02-01

    Spin-lattice relaxation rates of lead have been measured at 17.6T (156.9MHz) as a function of temperature in polycrystalline lead nitrate and lead molybdate. Comparing the results with relaxation rates measured at lower fields, it is found that at high fields and low temperature, chemical shift anisotropy (CSA) makes small but observable contributions to lead relaxation in both materials. At 17.6T and 200K, CSA accounts for about 15% of the observed relaxation rate. Above 300K, the dominant relaxation mechanism even at 17.6T is an indirect Raman process involving modulation of the Pb207 spin-rotation tensor, as first proposed by Grutzner et al. [J. Am. Chem. Soc. 123, 7094 (2001)] and later treated theoretically in more detail by Vega et al. [Phys. Rev. B 74, 214420 (2006)]. The improved signal to noise ratio at high fields makes it possible to quantify relaxation time anisotropy by analyzing saturation-recovery functions for individual frequencies on the powder pattern line shape. No orientation dependence is found for the spin-lattice relaxation rate of either material. It is argued from examination of the appropriate theoretical expressions, derived here for the first time, that the lack of observable relaxation time anisotropy is probably a general feature of this indirect Raman mechanism.

  7. New double molybdate Na9Fe(MoO4)6: Synthesis, structure, properties

    NASA Astrophysics Data System (ADS)

    Savina, Aleksandra A.; Solodovnikov, Sergey F.; Basovich, Olga M.; Solodovnikova, Zoya A.; Belov, Dmitry A.; Pokholok, Konstantin V.; Gudkova, Irina A.; Stefanovich, Sergey Yu.; Lazoryak, Bogdan I.; Khaikina, Elena G.

    2013-09-01

    A new double molybdate Na9Fe(MoO4)6 was synthesized using solid state reactions and studied with X-ray powder diffraction, second harmonic generation (SHG) technique, differential scanning calorimetry, X-ray fluorescence analysis, Mössbauer and dielectric impedance spectroscopy. Single crystals of Na9Fe(MoO4)6 were obtained and its structure was solved (the space group R3¯, a=14.8264(2), c=19.2402(3) Å, V=3662.79(9) Å3, Z=6, R=0.0132). The structure is related to that of sodium ion conductor II-Na3Fe2(AsO4)3. The basic structure units are polyhedral clusters composed of central FeО6 octahedron sharing edges with three Na(1)О6 octahedra. The clusters share common vertices with bridging МоО4 tetrahedra to form an open 3D framework where the cavities are occupied by Na(2) and Na(3) atoms. The compound melts incongruently at 904.7±0.2 K. Arrhenius type temperature dependence of electric conductivity σ has been registered in solid state (σ=6.8×10-2 S сm-1 at 800 K), thus allowing considering Na9Fe(MoO4)6 as a new sodium ion conductor.

  8. Two-photon interband absorption coefficients in tungstate and molybdate crystals

    NASA Astrophysics Data System (ADS)

    Lukanin, V. I.; Karasik, A. Ya.

    2015-02-01

    Two-photon absorption (TPA) coefficients were measured in tungstate and molybdate crystals - BaWO4, KGW, CaMoO4, BaMoO4, CaWO4, PbWO4 and ZnWO4 upon different orientations of excitation polarization with respect to the crystallographic axes. Trains of 25 ps pulses with variable radiation intensities of third (349 nm) harmonics of passively mode-locked 1047 nm Nd:YLF laser were used for interband two-photon excitation of the crystals. It was suggested that in the case, when 349 nm radiation pumping energy exceeds the bandgap width (hν>Eg), the nonlinear excitation process can be considered as two-step absorption. The interband two-photon absorption in all the studied crystals induces the following one-photon absorption from the exited states, which affects the nonlinear process dynamics and leads to a hysteresis in the dependence of the transmission on the excitation intensity. This fact was taken into account under analysis of the experimental dependences of the reciprocal transmission on the excitation intensity. Laser excitation in the transparency region of the crystals caused stimulated Raman scattering (SRS) not for all the crystals studied. The measured nonlinear coefficients allowed us to explain the suppression of SRS in crystals as a result of competition between the SRS and TPA.

  9. 21 CFR 73.1298 - Ferric ammonium ferrocyanide.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) Identity. (1) The color additive ferric ammonium ferrocyanide is the blue pigment obtained by oxidizing... product is filtered, washed, and dried. The pigment consists principally of ferric ammonium...

  10. 21 CFR 73.1298 - Ferric ammonium ferrocyanide.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) Identity. (1) The color additive ferric ammonium ferrocyanide is the blue pigment obtained by oxidizing... product is filtered, washed, and dried. The pigment consists principally of ferric ammonium...

  11. 21 CFR 73.1298 - Ferric ammonium ferrocyanide.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) Identity. (1) The color additive ferric ammonium ferrocyanide is the blue pigment obtained by oxidizing... product is filtered, washed, and dried. The pigment consists principally of ferric ammonium...

  12. 21 CFR 73.1298 - Ferric ammonium ferrocyanide.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) Identity. (1) The color additive ferric ammonium ferrocyanide is the blue pigment obtained by oxidizing... product is filtered, washed, and dried. The pigment consists principally of ferric ammonium...

  13. 21 CFR 73.1298 - Ferric ammonium ferrocyanide.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) Identity. (1) The color additive ferric ammonium ferrocyanide is the blue pigment obtained by oxidizing... product is filtered, washed, and dried. The pigment consists principally of ferric ammonium...

  14. Ammonium Hydrosulfide: Coloring Jupiter's Clouds

    NASA Astrophysics Data System (ADS)

    Loeffler, Mark J.; Hudson, Reggie L.; Chanover, Nancy J.; Simon, Amy A.

    2015-11-01

    The appearance and composition of Jupiter’s Great Red Spot (GRS) have been studied for over a century, yet there still is no consensus for what is causing the GRS’s color. As the GRS is believed to originate in tropospheric clouds, it seems likely that one or more cloud components may contribute to the GRS's color. Recently, we have begun to investigate whether either ammonium hydrosulfide (NH4SH), a predicted cloud component, or its radiation-chemical products can produce color and/or an ultraviolet-visible spectrum similar to what has been observed on Jupiter via remote sensing (e.g., Simon et al., 2015). Our initial experiments relied on infrared spectroscopy to quantify the radiolytic and thermal stability of NH4SH and to identify the new chemical products formed during MeV ion irradiation (Loeffler et al., 2015). This DPS presentation will cover some of our most recent results detailing the ultraviolet-visible spectral and color changes observed during irradiation and post-irradiation warming of NH4SH ices. This work is funded by NASA’s Outer Planets and Planetary Atmospheres programs.

  15. Phase diagram of ammonium nitrate

    SciTech Connect

    Dunuwille, Mihindra; Yoo, Choong-Shik

    2013-12-07

    Ammonium Nitrate (AN) is a fertilizer, yet becomes an explosive upon a small addition of chemical impurities. The origin of enhanced chemical sensitivity in impure AN (or AN mixtures) is not well understood, posing significant safety issues in using AN even today. To remedy the situation, we have carried out an extensive study to investigate the phase stability of AN and its mixtures with hexane (ANFO–AN mixed with fuel oil) and Aluminum (Ammonal) at high pressures and temperatures, using diamond anvil cells (DAC) and micro-Raman spectroscopy. The results indicate that pure AN decomposes to N{sub 2}, N{sub 2}O, and H{sub 2}O at the onset of the melt, whereas the mixtures, ANFO and Ammonal, decompose at substantially lower temperatures. The present results also confirm the recently proposed phase IV-IV{sup ′} transition above 17 GPa and provide new constraints for the melting and phase diagram of AN to 40 GPa and 400°C.

  16. Biodegradation of rocket propellent waste, ammonium perchlorate

    NASA Technical Reports Server (NTRS)

    Naqui, S. M. Z.

    1975-01-01

    The impact of the biodegradation rate of ammonium perchlorate on the environment was studied in terms of growth, metabolic rate, and total biomass of selected animal and plant species. Brief methodology and detailed results are presented.

  17. Electrochemically and bioelectrochemically induced ammonium recovery.

    PubMed

    Gildemyn, Sylvia; Luther, Amanda K; Andersen, Stephen J; Desloover, Joachim; Rabaey, Korneel

    2015-01-01

    Streams such as urine and manure can contain high levels of ammonium, which could be recovered for reuse in agriculture or chemistry. The extraction of ammonium from an ammonium-rich stream is demonstrated using an electrochemical and a bioelectrochemical system. Both systems are controlled by a potentiostat to either fix the current (for the electrochemical cell) or fix the potential of the working electrode (for the bioelectrochemical cell). In the bioelectrochemical cell, electroactive bacteria catalyze the anodic reaction, whereas in the electrochemical cell the potentiostat applies a higher voltage to produce a current. The current and consequent restoration of the charge balance across the cell allow the transport of cations, such as ammonium, across a cation exchange membrane from the anolyte to the catholyte. The high pH of the catholyte leads to formation of ammonia, which can be stripped from the medium and captured in an acid solution, thus enabling the recovery of a valuable nutrient. The flux of ammonium across the membrane is characterized at different anolyte ammonium concentrations and currents for both the abiotic and biotic reactor systems. Both systems are compared based on current and removal efficiencies for ammonium, as well as the energy input required to drive ammonium transfer across the cation exchange membrane. Finally, a comparative analysis considering key aspects such as reliability, electrode cost, and rate is made. This video article and protocol provide the necessary information to conduct electrochemical and bioelectrochemical ammonia recovery experiments. The reactor setup for the two cases is explained, as well as the reactor operation. We elaborate on data analysis for both reactor types and on the advantages and disadvantages of bioelectrochemical and electrochemical systems. PMID:25651406

  18. Sarcoplasmic reticulum calcium ATPase interactions with decaniobate, decavanadate, vanadate, tungstate and molybdate.

    PubMed

    Fraqueza, Gil; Ohlin, C André; Casey, William H; Aureliano, Manuel

    2012-02-01

    Over the last few decades there has been increasing interest in oxometalate and polyoxometalate applications to medicine and pharmacology. This interest arose, at least in part, due to the properties of these classes of compounds as anti-cancer, anti-diabetic agents, and also for treatment of neurodegenerative diseases, among others. However, our understanding of the mechanism of action would be improved if biological models could be used to clarify potential toxicological effects in main cellular processes. Sarcoplasmic reticulum (SR) vesicles, containing a large amount of Ca(2+)-ATPase, an enzyme that accumulates calcium by active transport using ATP, have been suggested as a useful model to study the effects of oxometalates on calcium homeostasis. In the present article, it is shown that decavanadate, decaniobate, vanadate, tungstate and molybdate, all inhibited SR Ca(2+)-ATPase, with the following IC(50) values: 15, 35, 50, 400 μM and 45 mM, respectively. Decaniobate (Nb(10)), is the strongest P-type enzyme inhibitor, after decavanadate (V(10)). Atomic-absorption spectroscopy (AAS) analysis, indicates that decavanadate binds to the protein with a 1:1 decavanadate:Ca(2+)-ATPase stoichiometry. Furthermore, V(10) binds with similar extension to all the protein conformations, which occur during calcium translocation by active transport, namely E1, E1P, E2 and E2P, as analysed by AAS. In contrast, it was confirmed that the binding of monomeric vanadate (H(2)VO(4)(2-); V(1)) to the calcium pump is favoured only for the E2 and E2P conformations of the ATPase, whereas no significant amount of vanadate is bound to the E1 and E1P conformations. Scatchard plot analysis, confirmed a 1:1 ratio for decavanadate-Ca(2+)-ATPase, with a dissociation constant, k(d) of 1 μM(-1). The interaction of decavanadate V(10)O(28)(6-) (V(10)) with Ca(2+)-ATPase is prevented by the isostructural and isoelectronic decaniobate Nb(10)O(28)(6-) (Nb(10)), whereas no significant effects were

  19. 21 CFR 172.430 - Iron ammonium citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Iron ammonium citrate. 172.430 Section 172.430... CONSUMPTION Anticaking Agents § 172.430 Iron ammonium citrate. Iron ammonium citrate may be safely used in... human consumption so that the level of iron ammonium citrate does not exceed 25 parts per million...

  20. 21 CFR 573.560 - Iron ammonium citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Iron ammonium citrate. 573.560 Section 573.560... Additive Listing § 573.560 Iron ammonium citrate. Iron ammonium citrate may be safely used in animal feed... consumption so that the level of iron ammonium citrate does not exceed 25 parts per million (0.0025...

  1. 21 CFR 172.430 - Iron ammonium citrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Iron ammonium citrate. 172.430 Section 172.430... CONSUMPTION Anticaking Agents § 172.430 Iron ammonium citrate. Iron ammonium citrate may be safely used in... human consumption so that the level of iron ammonium citrate does not exceed 25 parts per million...

  2. 21 CFR 573.560 - Iron ammonium citrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Iron ammonium citrate. 573.560 Section 573.560... Additive Listing § 573.560 Iron ammonium citrate. Iron ammonium citrate may be safely used in animal feed... consumption so that the level of iron ammonium citrate does not exceed 25 parts per million (0.0025...

  3. 21 CFR 573.560 - Iron ammonium citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Iron ammonium citrate. 573.560 Section 573.560... Additive Listing § 573.560 Iron ammonium citrate. Iron ammonium citrate may be safely used in animal feed... consumption so that the level of iron ammonium citrate does not exceed 25 parts per million (0.0025...

  4. 21 CFR 573.560 - Iron ammonium citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Iron ammonium citrate. 573.560 Section 573.560... Additive Listing § 573.560 Iron ammonium citrate. Iron ammonium citrate may be safely used in animal feed... consumption so that the level of iron ammonium citrate does not exceed 25 parts per million (0.0025...

  5. 21 CFR 172.430 - Iron ammonium citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Iron ammonium citrate. 172.430 Section 172.430 Food... Anticaking Agents § 172.430 Iron ammonium citrate. Iron ammonium citrate may be safely used in food in... consumption so that the level of iron ammonium citrate does not exceed 25 parts per million (0.0025...

  6. 21 CFR 172.430 - Iron ammonium citrate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Iron ammonium citrate. 172.430 Section 172.430... CONSUMPTION Anticaking Agents § 172.430 Iron ammonium citrate. Iron ammonium citrate may be safely used in... human consumption so that the level of iron ammonium citrate does not exceed 25 parts per million...

  7. 21 CFR 573.560 - Iron ammonium citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Iron ammonium citrate. 573.560 Section 573.560... Additive Listing § 573.560 Iron ammonium citrate. Iron ammonium citrate may be safely used in animal feed... consumption so that the level of iron ammonium citrate does not exceed 25 parts per million (0.0025...

  8. Biological reduction of uranium coupled with oxidation of ammonium by Acidimicrobiaceae bacterium A6 under iron reducing conditions.

    PubMed

    Gilson, Emily R; Huang, Shan; Jaffé, Peter R

    2015-11-01

    This study investigated the possibility of links between the biological immobilization of uranium (U) and ammonium oxidation under iron (Fe) reducing conditions. The recently-identified Acidimicrobiaceae bacterium A6 (ATCC, PTA-122488) derives energy from ammonium oxidation coupled with Fe reduction. This bacterium has been found in various soil and wetland environments, including U-contaminated wetland sediments. Incubations of Acidimicrobiaceae bacteria A6 with nontronite, an Fe(III)-rich clay, and approximately 10 µM U indicate that these bacteria can use U(VI) in addition to Fe(III) as an electron acceptor in the presence of ammonium. Measurements of Fe(II) production and ammonium oxidation support this interpretation. Concentrations of approximately 100 µM U were found to entirely inhibit Acidimicrobiaceae bacteria A6 activity. These results suggest that natural sites of active ammonium oxidation under Fe reducing conditions by Acidimicrobiaceae bacteria A6 could be hotspots of U immobilization by bioreduction. This is the first report of biological U reduction that is not coupled to carbon oxidation. PMID:26525893

  9. Chromium(VI) generation in vadose zone soils and alluvial sediments of the southwestern Sacramento Valley, California: a potential source of geogenic Cr(VI) to groundwater

    USGS Publications Warehouse

    Mills, Christopher T.; Morrison, Jean M.; Goldhaber, Martin B.; Ellefsen, Karl J.

    2011-01-01

    very small fraction of the total solid phase Cr, they are a potentially important source for Cr(VI) to groundwater. Enhanced groundwater recharge through the vadose zone due to irrigation could carry Cr(VI) from the vadose zone to the groundwater and may be the mechanism responsible for the correlation observed between elevated Cr(VI) and NO3- source concentrations in previously published data for valley groundwaters. Incubation of a valley subsoil showed a Cr(VI) production rate of 24 μg kg−1 a−1 suggesting that field Cr(VI) concentrations could be regenerated annually. Increased Cr(VI) production rates in H+-amended soil incubations indicate that soil acidification processes such as nitrification of ammonium in fertilizers could potentially increase the occurrence of geogenic Cr(VI) in groundwater. Thus, despite the natural origin of the Cr, Cr(VI) generation in the Sacramento Valley soils and sediments has the potential to be influenced by human activities.

  10. Salivary carbonic anhydrase isoenzyme VI

    PubMed Central

    Kivelä, Jyrki; Parkkila, Seppo; Parkkila, Anna-Kaisa; Leinonen, Jukka; Rajaniemi, Hannu

    1999-01-01

    The carbonic anhydrases (CAs) participate in the maintenance of pH homeostasis in various tissues and biological fluids of the human body by catalysing the reversible reaction CO2+ H2O ⇌ HCO3−+ H+ (Davenport & Fisher, 1938; Davenport, 1939; Maren, 1967). Carbonic anhydrase isoenzyme VI (CA VI) is the only secretory isoenzyme of the mammalian CA gene family. It is exclusively expressed in the serous acinar cells of the parotid and submandibular glands, from where it is secreted into the saliva. In this review, we will discuss recent advances in research focused on the physiological role of salivary CA VI in the oral cavity and upper alimentary canal. PMID:10523402

  11. Efficient adsorption of both methyl orange and chromium from their aqueous mixtures using a quaternary ammonium salt modified chitosan magnetic composite adsorbent.

    PubMed

    Li, Kun; Li, Pei; Cai, Jun; Xiao, Shoujun; Yang, Hu; Li, Aimin

    2016-07-01

    A quaternary ammonium salt modified chitosan magnetic composite adsorbent (CS-CTA-MCM) was prepared by combination of Fe3O4 nanoparticles. Various techniques were used to characterize the molecular structure, surface morphology, and magnetic feature of this composite adsorbent. CS-CTA-MCM was employed for the removal of Cr(VI) and methyl orange (MO), an anionic dye, from water in respective single and binary systems. Compared with chitosan magnetic adsorbent (CS-MCM) without modification, CS-CTA-MCM shows evidently improved adsorption capacities for both pollutants ascribed to the additional quaternary ammonium salt groups. Based on the adsorption equilibrium study, MO bears more affinity to CS-CTA-MCM than Cr(VI) causing a considerable extent of preferential adsorption of dye over metal ions in their aqueous mixture. However, at weak acidic solutions, Cr(VI) adsorption is evidently improved due to more efficient Cr(VI) forms, i.e. dichromate and monovalent chromate, binding to this chitosan-based adsorbent. Thus chromium could be efficient removal together with MO at suitable pH conditions. The adsorption isotherms and kinetics indicate that adsorptions of Cr(VI) and MO by CS-CTA-MCM both follow a homogeneous monolayer chemisorption process. This magnetic adsorbent after saturated adsorption could be rapidly separated from water and easily regenerated using dilute NaOH aqueous solutions then virtually reused with little adsorption capacity loss. PMID:27060639

  12. Calcium sulphate in ammonium sulphate solution

    USGS Publications Warehouse

    Sullivan, E.C.

    1905-01-01

    Calcium sulphate, at 25?? C., is two-thirds as soluble in dilute (o.i mol per liter) and twice as soluble in concentrated (3 mois per liter) ammonium sulphate solution as in water. The specific electric conductivity of concentrated ammonium sulphate solutions is lessened by saturating with calcium sulphate. Assuming that dissociation of ammonium sulphate takes place into 2NH4?? and SO4" and of calcium sulphate into Ca and SO4" only, and that the conductivity is a measure of such dissociation, the solubility of calcium sulphate in dilute ammonium sulphate solutions is greater than required by the mass-law. The conductivity of the dilute mixtures may be accurately calculated by means of Arrhenius' principle of isohydric solutions. In the data obtained in these calculations, the concentration of non-dissociated calcium sulphate decreases with increasing ammonium sulphate. The work as a whole is additional evidence of the fact that we are not yet in possession of all the factors necessary for reconciling the mass-law to the behavior of electrolytes. The measurements above described were made in the chemical laboratory of the University of Michigan.

  13. Collagen VI related muscle disorders

    PubMed Central

    Lampe, A; Bushby, K

    2005-01-01

    Mutations in the genes encoding collagen VI (COL6A1, COL6A2, and COL6A3) cause Bethlem myopathy (BM) and Ullrich congenital muscular dystrophy (UCMD), two conditions which were previously believed to be completely separate entities. BM is a relatively mild dominantly inherited disorder characterised by proximal weakness and distal joint contractures. UCMD was originally described as an autosomal recessive condition causing severe muscle weakness with proximal joint contractures and distal hyperlaxity. Here we review the clinical phenotypes of BM and UCMD and their diagnosis and management, and provide an overview of the current knowledge of the pathogenesis of collagen VI related disorders. PMID:16141002

  14. Benchmark binding energies of ammonium and alkyl-ammonium ions interacting with water. Are ammonium-water hydrogen bonds strong?

    NASA Astrophysics Data System (ADS)

    Vallet, Valérie; Masella, Michel

    2015-01-01

    Alkyl-ammonium ion/water interactions are investigated using high level quantum computations, yielding thermodynamics data in good agreement with gas-phase experiments. Alkylation and hydration lead to weaken the NHsbnd O hydrogen bonds. Upon complete hydration by four water molecules, their main features are close to those of the OHsbnd O bond in the isolated water dimer. Energy decomposition analyses indicate that hydration of alkyl-ammonium ions are mainly due to electrostatic/polarization effects, as for hard monoatomic cations, but with a larger effect of dispersion.

  15. Simulation of the inhibition of microbial sulfate reduction in a two-compartment upflow bioreactor subjected to molybdate injection.

    PubMed

    de Jesus, E B; de Andrade Lima, L R P

    2016-08-01

    Souring of oil fields during secondary oil recovery by water injection occurs mainly due to the action of sulfate-reducing bacteria (SRB) adhered to the rock surface in the vicinity of injection wells. Upflow packed-bed bioreactors have been used in petroleum microbiology because of its similarity to the oil field near the injection wells or production. However, these reactors do not realistically describe the regions near the injection wells, which are characterized by the presence of a saturated zone and a void region close to the well. In this study, the hydrodynamics of the two-compartment packing-free/packed-bed pilot bioreactor that mimics an oil reservoir was studied. The packed-free compartment was modeled using a continuous stirred tank model with mass exchange between active and stagnant zones, whereas the packed-bed compartment was modeled using a piston-dispersion-exchange model. The proposed model adequately represents the hydrodynamic of the packed-free/packed-bed bioreactor while the simulations provide important information about the characteristics of the residence time distribution (RTD) curves for different sets of model parameters. Simulations were performed to represent the control of the sulfate-reducing bacteria activity in the bioreactor with the use of molybdate in different scenarios. The simulations show that increased amounts of molybdate cause an effective inhibition of the souring sulfate-reducing bacteria activity. PMID:27126499

  16. Mechanism of Selective Ammoxidation of Propene to Acrylonitrile on Bismuth Molybdates from Quantum Mechanical Calculations

    SciTech Connect

    Pudar, Sanja; Oxgaard, Jonas; Goddard, William A

    2010-08-25

    In order to understand the mechanism for selective ammoxidation of propene to acrylonitrile by bismuth molybdates, we report quantum mechanical studies (using the B3LYP flavor of density functional theory) for the various steps involved in converting the allyl-activated intermediate to acrylonitrile over molybdenum oxide (using a Mo3O9 cluster model) under conditions adjusted to describe both high and low partial pressures of NH3 in the feed. We find that the rate-determining step in converting of allyl to acrylonitrile at all feed partial pressures is the second hydrogen abstraction from the nitrogen-bound allyl intermediate (Mo-NH-CH2-CH=CH2) to form Mo-NH=CH-CH=CH2). We find that imido groups (Mo=NH) have two roles: (1) a direct effect on H abstraction barriers, H abstraction by an imido moiety is (~8 kcal/mol) more favorable than abstraction by an oxo moiety (Mo=O), and (2) an indirect effect, the presence of spectator imido groups decreases the H abstraction barriers by an additional ~15 kcal/mol. Therefore, at higher NH3 pressures (which increases the number of Mo=NH groups), the second H abstraction barrier decreases significantly, in agreement with experimental observations that propene conversion is higher at higher partial pressures of NH3. At high NH3 pressures we find that the final hydrogen abstraction has a high barrier [ΔHfourth-ab = 31.6 kcal/mol compared to ΔHsecond-ab = 16.4 kcal/mol] due to formation of low Mo oxidation states in the final state. However, we find that reoxidizing the surface prior to the last hydrogen abstraction leads to a significant reduction of this barrier to ΔHfourth-ab = 15.9 kcal/mol, so that this step is no longer rate determining. Therefore, we conclude that reoxidation during the reaction is necessary for facile conversion of allyl to

  17. On the evaporation of ammonium sulfate solution

    PubMed Central

    Drisdell, Walter S.; Saykally, Richard J.; Cohen, Ronald C.

    2009-01-01

    Aqueous evaporation and condensation kinetics are poorly understood, and uncertainties in their rates affect predictions of cloud behavior and therefore climate. We measured the cooling rate of 3 M ammonium sulfate droplets undergoing free evaporation via Raman thermometry. Analysis of the measurements yields a value of 0.58 ± 0.05 for the evaporation coefficient, identical to that previously determined for pure water. These results imply that subsaturated aqueous ammonium sulfate, which is the most abundant inorganic component of atmospheric aerosol, does not affect the vapor–liquid exchange mechanism for cloud droplets, despite reducing the saturation vapor pressure of water significantly. PMID:19861551

  18. On the evaporation of ammonium sulfate solution

    SciTech Connect

    Drisdell, Walter S.; Saykally, Richard J.; Cohen, Ronald C.

    2009-07-16

    Aqueous evaporation and condensation kinetics are poorly understood, and uncertainties in their rates affect predictions of cloud behavior and therefore climate. We measured the cooling rate of 3 M ammonium sulfate droplets undergoing free evaporation via Raman thermometry. Analysis of the measurements yields a value of 0.58 {+-} 0.05 for the evaporation coefficient, identical to that previously determined for pure water. These results imply that subsaturated aqueous ammonium sulfate, which is the most abundant inorganic component of atmospheric aerosol, does not affect the vapor-liquid exchange mechanism for cloud droplets, despite reducing the saturation vapor pressure of water significantly.

  19. Quadrupole interactions in tetraoxoferrates (VI)

    NASA Astrophysics Data System (ADS)

    Dedushenko, Sergey K.; Perfiliev, Yurii D.; Rusakov, Vyacheslav S.; Gapochka, Alexei M.

    2013-05-01

    An applicability of the point charge approach for calculations of quadrupole splittings in Mössbauer spectra of ferrates(VI) was studied. The reasonable correlation between calculated and experimental splittings was observed for the majority of ferrates excepting K3Na(FeO4)2. The comparison of ferrates and chromates was made using calculated nucleus independent coefficient.

  20. Protostars and Planets VI

    NASA Astrophysics Data System (ADS)

    Beuther, Henrik; Klessen, Ralf S.; Dullemond, Cornelis P.; Henning, Thomas

    star and planet formation. They are used by students to dive into new topics, and they are much valued by experienced researchers as a comprehensive overview of the field with all its interactions. We hope that you will enjoy reading (and learning from) this book as much as we do. The organization of the Protostars and Planets conference was carried out in close collaboration between the Max Planck Institute for Astronomy and the Center for Astronomy of the University Heidelberg, with generous support from the German Science Foundation. This volume is a product of effort and care by many people. First and foremost, we want to acknowledge the 250 contributing authors, as it is only due to their expertise and knowledge that such a comprehensive review compendium in all its depth and breadth is possible. The Protostars and Planets VI conference and this volume was a major undertaking, with support and contributions by many people and institutions. We like to thank the members of the Scientific Advisory Committee who selected the 38 teams and chapters out of more than 120 submitted proposals. Similarly, we are grateful to the reviewers, who provided valuable input and help to the chapter authors. The book would also not have been possible without the great support of Renée Dotson and other staff from USRA’s Lunar and Planetary Institute, who handled the detailed processing of all manuscripts and the production of the book, and of Allyson Carter and other staff from the University of Arizona Press. We are also grateful to Richard Binzel, the General Editor of the Space Science Series, for his constant support during the long process, from the original concept to this final product. Finally, we would like to express a very special thank you to the entire conference local organizing committee, and in particular, Carmen Cuevas and Natali Jurina, for their great commitment to the project and for a very fruitful and enjoyable collaboration.

  1. Heterogeneity of Collagen VI Microfibrils

    PubMed Central

    Maaß, Tobias; Bayley, Christopher P.; Mörgelin, Matthias; Lettmann, Sandra; Bonaldo, Paolo; Paulsson, Mats; Baldock, Clair; Wagener, Raimund

    2016-01-01

    Collagen VI, a collagen with uncharacteristically large N- and C-terminal non-collagenous regions, forms a distinct microfibrillar network in most connective tissues. It was long considered to consist of three genetically distinct α chains (α1, α2, and α3). Intracellularly, heterotrimeric molecules associate to form dimers and tetramers, which are then secreted and assembled to microfibrils. The identification of three novel long collagen VI α chains, α4, α5, and α6, led to the question if and how these may substitute for the long α3 chain in collagen VI assembly. Here, we studied structural features of the novel long chains and analyzed the assembly of these into tetramers and microfibrils. N- and C-terminal globular regions of collagen VI were recombinantly expressed and studied by small angle x-ray scattering (SAXS). Ab initio models of the N-terminal globular regions of the α4, α5, and α6 chains showed a C-shaped structure similar to that found for the α3 chain. Single particle EM nanostructure of the N-terminal globular region of the α4 chain confirmed the C-shaped structure revealed by SAXS. Immuno-EM of collagen VI extracted from tissue revealed that like the α3 chain the novel long chains assemble to homotetramers that are incorporated into mixed microfibrils. Moreover, SAXS models of the C-terminal globular regions of the α1, α2, α4, and α6 chains were generated. Interestingly, the α1, α2, and α4 C-terminal globular regions dimerize. These self-interactions may play a role in tetramer formation. PMID:26742845

  2. 21 CFR 556.375 - Maduramicin ammonium.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Maduramicin ammonium. 556.375 Section 556.375 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS TOLERANCES FOR RESIDUES OF NEW ANIMAL DRUGS IN FOOD Specific Tolerances for Residues of New Animal Drugs §...

  3. 21 CFR 573.170 - Ammonium formate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) The additive is manufactured by the reaction of 99.5 percent ammonia gas and 99 percent formic acid in...) To assure safe use of the additive, in addition to the other information required by the Federal Food... labeled as containing ammonium formate. (d) To assure safe use of the additive, in addition to the...

  4. 21 CFR 573.170 - Ammonium formate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) The additive is manufactured by the reaction of 99.5 percent ammonia gas and 99 percent formic acid in...) To assure safe use of the additive, in addition to the other information required by the Federal Food... labeled as containing ammonium formate. (d) To assure safe use of the additive, in addition to the...

  5. 21 CFR 573.170 - Ammonium formate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... is manufactured by the reaction of 99.5 percent ammonia gas and 99 percent formic acid in a... safe use of the additive, in addition to the other information required by the Federal Food, Drug, and... ammonium formate. (d) To assure safe use of the additive, in addition to the other information required...

  6. 21 CFR 184.1137 - Ammonium carbonate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ammonium carbonate. 184.1137 Section 184.1137 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) DIRECT FOOD SUBSTANCES AFFIRMED AS GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS...

  7. 21 CFR 184.1143 - Ammonium sulfate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ammonium sulfate. 184.1143 Section 184.1143 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) DIRECT FOOD SUBSTANCES AFFIRMED AS GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS...

  8. 21 CFR 184.1137 - Ammonium carbonate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ammonium carbonate. 184.1137 Section 184.1137 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) DIRECT FOOD SUBSTANCES AFFIRMED AS GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS...

  9. Cyclo­hexyl­ammonium nitrate

    PubMed Central

    Bagabas, Abdulaziz A.; Aboud, Mohamed F. A.; Shemsi, Ahsan M.; Addurihem, Emad S.; Al-Othman, Zeid A.; Chidan Kumar, C. S.; Fun, Hoong-Kun

    2014-01-01

    In the title salt, C6H14N+·NO3 −, the cyclo­hexyl ring adopts a chair conformation. The ammonium group occupies an equatorial position and the crystal struture is stabilized by inter­molecular N—H⋯O hydrogen-bonding inter­actions, resulting in a three-dimensional network. PMID:24764971

  10. 76 FR 70366 - Ammonium Nitrate Security Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-14

    ... Department previously announced a series of public meetings on the same topic on October 2, 2011 (see 76 FR... public comment on August 3, 2011. See 73 FR 64280 (advance notice of proposed rulemaking); 76 FR 46908... the Department's Ammonium Nitrate Security Program Web site, at...

  11. 21 CFR 184.1133 - Ammonium alginate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...: Category of food Maximum level of use in food (as served) (percent) Functional use Confections, frostings... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ammonium alginate. 184.1133 Section 184.1133 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD...

  12. 21 CFR 184.1133 - Ammonium alginate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ammonium alginate. 184.1133 Section 184.1133 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) DIRECT FOOD SUBSTANCES AFFIRMED AS GENERALLY RECOGNIZED AS SAFE Listing of Specific Substances Affirmed as GRAS...

  13. 21 CFR 582.1137 - Ammonium carbonate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ammonium carbonate. 582.1137 Section 582.1137 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE General Purpose...

  14. 21 CFR 582.1135 - Ammonium bicarbonate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ammonium bicarbonate. 582.1135 Section 582.1135 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE General Purpose...

  15. 21 CFR 582.1137 - Ammonium carbonate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Ammonium carbonate. 582.1137 Section 582.1137 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE General Purpose...

  16. 21 CFR 582.1135 - Ammonium bicarbonate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Ammonium bicarbonate. 582.1135 Section 582.1135 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE General Purpose...

  17. 21 CFR 582.1139 - Ammonium hydroxide.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Ammonium hydroxide. 582.1139 Section 582.1139 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE General Purpose...

  18. 21 CFR 582.1139 - Ammonium hydroxide.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Ammonium hydroxide. 582.1139 Section 582.1139 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE General Purpose...

  19. 21 CFR 582.1137 - Ammonium carbonate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Ammonium carbonate. 582.1137 Section 582.1137 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE General Purpose...

  20. 21 CFR 582.1139 - Ammonium hydroxide.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ammonium hydroxide. 582.1139 Section 582.1139 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE General Purpose...

  1. 21 CFR 582.1135 - Ammonium bicarbonate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Ammonium bicarbonate. 582.1135 Section 582.1135 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE General Purpose...

  2. Diamond Head Revisited with Ammonium Dichromate.

    ERIC Educational Resources Information Center

    Arrigoni, Edward

    1981-01-01

    The classroom demonstration using ammonium dichromate to simulate a volcanic eruption can be modified into a more dramatic and accurate representation of the geologic processes involved in the formation of a volcanic crater. The materials, demonstration setup, safety procedures, and applications to instruction are presented. (Author/WB)

  3. Near infrared detection of ammonium minerals.

    USGS Publications Warehouse

    Krohn, M.D.; Altaner, S.P.

    1987-01-01

    Diagnostic near-infrared spectral features have been identified for minerals with ammonium (NH4+) bound in the crystal structure. Near-infrared detection of NH4-bearing minerals may provide useful information for prospecting for certain ore deposits and may provide a better understanding of the nitrogen cycle within geologic environments.-from Authors

  4. 21 CFR 573.170 - Ammonium formate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) The additive is manufactured by the reaction of 99.5 percent ammonia gas and 99 percent formic acid in a continuous loop reactor to produce a solution made up of 37 percent ammonium salt of formic acid and 62 percent formic acid. (b) The additive is used or intended for use as a feed acidifying...

  5. MECHANISM BY WHICH AMMONIUM FERTILIZERS KILL LARKSPUR

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Environmental concerns of using pesticides on public lands have greatly reduced the use of herbicides to control tall larkspur (Delphinium barbeyi). Alternative methods of control have used ammonium sulfate placed in the crown of individual plants to kill larkspur. The objective of this study was ...

  6. 76 FR 47238 - Ammonium Nitrate From Russia

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-04

    ...)). Background The Commission instituted this review on March 1, 2011 (76 FR 11273) and determined on June 6, 2011 that it would conduct an expedited review (76 FR 34749, June 14, 2011). The Commission transmitted... COMMISSION Ammonium Nitrate From Russia Determination On the basis of the record \\1\\ developed in the...

  7. 21 CFR 184.1139 - Ammonium hydroxide.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... specifications of the Food Chemicals Codex, 3d Ed. (1981), p. 20, which is incorporated by reference. Copies are... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ammonium hydroxide. 184.1139 Section 184.1139 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD...

  8. 21 CFR 184.1135 - Ammonium bicarbonate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... ingredient meets the specifications of the Food Chemicals Codex, 3d Ed. (1981), p. 19, which is incorporated... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ammonium bicarbonate. 184.1135 Section 184.1135 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED)...

  9. Adsorption of methyl orange and Cr(VI) on mesoporous TiO2 prepared by hydrothermal method.

    PubMed

    Asuha, S; Zhou, X G; Zhao, S

    2010-09-15

    Mesoporous TiO(2) was synthesized by a hydrothermal method using cetyltrimethyl ammonium bromide (CTAB) as a structure-directing agent, and its adsorption abilities for the removal of methyl orange (MO) and Cr(VI) from waste waters were investigated. Transmission electron micrograph (TEM) observations together with nitrogen adsorption-desorption measurements show the formation of mesoporous TiO(2) with an average pore size of 5.2 nm and a surface area of 161.2 m(2)/g. The adsorption data for both MO and Cr(VI) fit well with either Langmuir or Freundlich adsorption model. The adsorption for MO is slightly influenced by pH of the solutions, while that for Cr(VI) is strongly dependent on solution pH. By an increase in solution pH from 3 to 12, the adsorbed percentage of MO decreases from ca. 87 to 78%; however, the adsorbed percentage of Cr(VI) decreases from ca. 45 to 0%. The maximum adsorption capacities of the mesoporous TiO(2) for MO and Cr(VI) are determined to be 454.5 and 33.9 mg/g, respectively, which suggests that the mesoporous TiO(2) is an excellent adsorbent for MO and Cr(VI). PMID:20510510

  10. 40 CFR 721.4095 - Quaternary ammonium alkyltherpropyl trialkylamine halides.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... trialkylamine halides. 721.4095 Section 721.4095 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.4095 Quaternary ammonium alkyltherpropyl trialkylamine halides. (a... generically as quaternary ammonium alkyltherpropyl trialkylamine halides (PMNs...

  11. 21 CFR 184.1296 - Ferric ammonium citrate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) ammonium citrate, CAS Reg. No. 1332-98-5) is a complex salt of undetermined structure composed of 16.5 to... (iron (III) ammonium citrate, CAS Reg. No. 1333-00-2) is a complex salt of undetermined...

  12. Summary report of session VI

    SciTech Connect

    Weiren Chou et al.

    2002-08-19

    This report gives a brief review of the presentations in Session VI of the Ecloud'02 Workshop and summarizes the major points during the discussions. Some points (e.g., the critical mass phenomenon) are not conclusive and even controversial. But it has been agreed that further investigations are warranted. The topic of Session VI in the Ecloud'02 workshop is ''Discussions of future studies, collaborations and possible solutions.'' Half of the session is devoted to presentations, another half to discussions. This report will focus on the latter. There are six presentations: (1) R. Macek, Possible cures to the e-cloud problem; (2) G. Rumolo, Driving the electron-cloud instability by an electron cooler; (3) U. Iriso Ariz, RF test benches for electron-cloud studies; (4) F. Caspers, Stealth clearing electrodes; (5) F. Ruggiero, Future electron-cloud studies at CERN; and (6) E. Perevedentsev, Beam-beam and transverse impedance model.

  13. Directional Mechanosensing in Myosin VI

    NASA Astrophysics Data System (ADS)

    Yang, Yubo; Tehver, Riina

    2013-03-01

    Myosin is a family of versatile motor proteins that perform various tasks, such as organelle transport, anchoring and cell deformation. Although the general mechanism of the motors has been fairly well established, details on dynamic aspects like force response of the motor, and force propagation are yet to be fully understood. In this poster, we present the response of the ATP binding region to force exerted on the tail domain in order to test the proposed tension-dependent gating mechanism of myosin VI processive motion. We employed the Self-Organized Polymer model in a computer simulation to explore the effect. Current results show that the ATP binding domain of myosin VI indeed exhibits tension dependence - both structurally and dynamically.

  14. 21 CFR 184.1141a - Ammonium phosphate, monobasic.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ammonium phosphate, monobasic. 184.1141a Section... SAFE Listing of Specific Substances Affirmed as GRAS § 184.1141a Ammonium phosphate, monobasic. (a) Ammonium phosphate, monobasic (NH4H2PO4, CAS Reg. No. 7722-76-1) is manufactured by reacting ammonia...

  15. 21 CFR 184.1141a - Ammonium phosphate, monobasic.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ammonium phosphate, monobasic. 184.1141a Section... SAFE Listing of Specific Substances Affirmed as GRAS § 184.1141a Ammonium phosphate, monobasic. (a) Ammonium phosphate, monobasic (NH4H2PO4, CAS Reg. No. 7722-76-1) is manufactured by reacting ammonia...

  16. 21 CFR 582.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Aluminum ammonium sulfate. 582.1127 Section 582.1127 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Additives § 582.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate. (b) Conditions...

  17. 21 CFR 182.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Aluminum ammonium sulfate. 182.1127 Section 182.1127 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Food Substances § 182.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate....

  18. 21 CFR 582.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Aluminum ammonium sulfate. 582.1127 Section 582.1127 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Additives § 582.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate. (b) Conditions...

  19. 21 CFR 182.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Aluminum ammonium sulfate. 182.1127 Section 182.1127 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Food Substances § 182.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate....

  20. 21 CFR 582.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Aluminum ammonium sulfate. 582.1127 Section 582.1127 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Additives § 582.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate. (b) Conditions...

  1. 21 CFR 182.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Aluminum ammonium sulfate. 182.1127 Section 182.1127 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Food Substances § 182.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate....

  2. 21 CFR 182.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Aluminum ammonium sulfate. 182.1127 Section 182...) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Multiple Purpose GRAS Food Substances § 182.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate. (b) Conditions of use. This substance is...

  3. 21 CFR 582.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Aluminum ammonium sulfate. 582.1127 Section 582.1127 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Additives § 582.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate. (b) Conditions...

  4. 21 CFR 582.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Aluminum ammonium sulfate. 582.1127 Section 582.1127 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Additives § 582.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate. (b) Conditions...

  5. 21 CFR 182.1127 - Aluminum ammonium sulfate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Aluminum ammonium sulfate. 182.1127 Section 182.1127 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Food Substances § 182.1127 Aluminum ammonium sulfate. (a) Product. Aluminum ammonium sulfate....

  6. 21 CFR 73.1025 - Ferric ammonium citrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Ferric ammonium citrate. 73.1025 Section 73.1025 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1025 Ferric ammonium citrate. (a) Identity. The color additive ferric ammonium...

  7. 40 CFR 721.10099 - Dialkyl dimethyl ammonium carbonate (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Dialkyl dimethyl ammonium carbonate... Specific Chemical Substances § 721.10099 Dialkyl dimethyl ammonium carbonate (generic). (a) Chemical... as dialkyl dimethyl ammonium carbonate (1:1) (PMN P-03-715) is subject to reporting under...

  8. 40 CFR 721.10302 - Zinc ammonium phosphate (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Zinc ammonium phosphate (generic). 721... Substances § 721.10302 Zinc ammonium phosphate (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as zinc ammonium phosphate (PMN...

  9. 40 CFR 721.10302 - Zinc ammonium phosphate (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Zinc ammonium phosphate (generic). 721... Substances § 721.10302 Zinc ammonium phosphate (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as zinc ammonium phosphate (PMN...

  10. 40 CFR 721.10302 - Zinc ammonium phosphate (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Zinc ammonium phosphate (generic). 721... Substances § 721.10302 Zinc ammonium phosphate (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as zinc ammonium phosphate (PMN...